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Goggins E, Mironchik Y, Kakkad S, Jacob D, Wildes F, Bhujwalla ZM, Krishnamachary B. Reprogramming of VEGF-mediated extracellular matrix changes through autocrine signaling. Cancer Biol Ther 2023; 24:2184145. [PMID: 37389973 PMCID: PMC10012930 DOI: 10.1080/15384047.2023.2184145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 01/20/2023] [Accepted: 01/30/2023] [Indexed: 03/11/2023] Open
Abstract
Vascular endothelial growth factor (VEGF) plays key roles in angiogenesis, vasculogenesis, and wound healing. In cancers, including triple negative breast cancer (TNBC), VEGF has been associated with increased invasion and metastasis, processes that require cancer cells to traverse through the extracellular matrix (ECM) and establish angiogenesis at distant sites. To further understand the role of VEGF in modifying the ECM, we characterized VEGF-mediated changes in the ECM of tumors derived from TNBC MDA-MB-231 cells engineered to overexpress VEGF. We established that increased VEGF expression by these cells resulted in tumors with reduced collagen 1 (Col1) fibers, fibronectin, and hyaluronan. Molecular characterization of tumors identified an increase of MMP1, uPAR, and LOX, and a decrease of MMP2, and ADAMTS1. α-SMA, a marker of cancer associated fibroblasts (CAFs), increased, and FAP-α, a marker of a subset of CAFs associated with immune suppression, decreased with VEGF overexpression. Analysis of human data from The Cancer Genome Atlas Program confirmed mRNA differences for several molecules when comparing TNBC with high and low VEGF expression. We additionally characterized enzymatic changes induced by VEGF overexpression in three different cancer cell lines that clearly identified autocrine-mediated changes, specifically uPAR, in these enzymes. Unlike the increase of Col1 fibers and fibronectin mediated by VEGF during wound healing, in the TNBC model, VEGF significantly reduced key protein components of the ECM. These results further expand our understanding of the role of VEGF in cancer progression and identify potential ECM-related targets to disrupt this progression.
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Affiliation(s)
- Eibhlin Goggins
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Yelena Mironchik
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Samata Kakkad
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Desmond Jacob
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Flonne Wildes
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Zaver M. Bhujwalla
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Department of Radiation Oncology and Molecular Radiation Sciences, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Balaji Krishnamachary
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
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Krishnamachary B, Sivakumar I, Mironchik Y, Sharma RK, Bharti SK, Penet MF, Winnard P, Wildes F, Goggins E, Maitra A, Goggins MG, Bhujwalla ZM. Abstract 2354: Downregulating the glutamine transporter, SLC1A5, significantly reduces cachexia in a PDAC xenograft. Cancer Res 2021. [DOI: 10.1158/1538-7445.am2021-2354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Cachexia occurs with high frequency and severity in pancreatic ductal adenocarcinoma (PDAC) patients [1]. Cachectic patients experience a wide range of symptoms affecting the function of organs such as muscle, liver, brain, and heart, causing significant morbidity [2]. In high-resolution 1H magnetic resonance spectroscopy (MRS) studies of extracts, we previously observed significant perturbation of glutamine in the brain and plasma of mice with a cachexia-inducing PDAC xenograft [3] that prompted us to evaluate the effects of modifying tumor glutamine metabolism on cachexia. We investigated tumors derived from cachexia-inducing Pa04C cells engineered to express shRNA against the glutamine transporter, SLC1A5, glutaminase (GLS) 1, and GLS 2. Patient-derived cachexia-inducing Pa04C cells were stably transduced with virions that expressed shRNA against GLS1 or GLS2 or SLC1A5. Pooled clones were obtained with puromycin selection. Empty vector (EV) cells were also established. Downregulation of target genes was confirmed with mRNA and protein expression characterization. The effects of gene knockdown on tumor growth and weight-loss were determined following subcutaneous inoculation of engineered cells or wild type cells in SCID mice. Longitudinal tumor growth, weights and percent weight changes were determined in 7 wild type (WT), 7 EV, 9 GLS1 downregulated, 9 GLS2 downregulated, and 9 SLC1A5 downregulated tumor bearing mice. Once tumors were ~500 mm3 in volume, tumors were harvested from euthanized mice, and snap frozen for molecular analysis. Protein and mRNA obtained from tumors was validated for downregulation of target genes. Efficient downregulation of SLC1A5, GLS1 and GLS2 mRNA and protein was confirmed in tumors. Downregulating SLC1A5 significantly reduced tumor growth. But, downregulating GLS1 or GLS2 did not reduce tumor growth and, in fact, GLS1 downregulated tumors grew significantly faster than WT or EV tumors. Importantly, for comparable tumor volumes, we found that body weight loss was markedly reduced in mice with SLC1A5 downregulated tumors. Although GLS1 downregulated tumors grew faster than WT tumors, weight loss was attenuated at comparable tumor volumes in these tumors although not to the same extent as in SLC1A5 downregulated tumors. These data highlight potential role of SLC1A5 in PDAC tumor treatment and in the treatment of PDAC-induced cachexia, and support targeting the glutamine/glutamate axis in PDAC to reduce or reverse cachexia.Supported by NIH R35 CA209960 and R01 CA193365. 1. Fearon KC, Baracos VE. Cachexia in pancreatic cancer: new treatment options and measures of success. 2010; 2. Inui A. Cancer anorexia-cachexia syndrome: current issues in research and management. CA Cancer J Clin. 2002; 3. Winnard PT, Jr., et al., Brain metabolites in cholinergic and glutamatergic pathways are altered by pancreatic cancer cachexia. J Cachexia Sarcopenia Muscle. 2020.
Citation Format: Balaji Krishnamachary, Ishwarya Sivakumar, Yelena Mironchik, Raj Kumar Sharma, Santosh Kumar Bharti, Marie-France Penet, Paul Winnard, Flonne Wildes, Eibhlin Goggins, Anirban Maitra, Michael G. Goggins, Zaver M. Bhujwalla. Downregulating the glutamine transporter, SLC1A5, significantly reduces cachexia in a PDAC xenograft [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2354.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Anirban Maitra
- 2The University of Texas MD Anderson Cancer Center, Houston, TX
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Pacheco-Torres J, Shah T, Brennen WN, Wildes F, Bhujwalla ZM. Abstract 2896: Effects of hypoxia on normal prostate fibroblast and prostate cancer associated fibroblast metabolism and matrix degradation. Cancer Res 2021. [DOI: 10.1158/1538-7445.am2021-2896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Synopsis: Fibroblasts are versatile cells that produce several ECM proteins such as collagen 1 as well as degradative enzymes such as matrix metalloproteinases. In cancer, fibroblasts play a significant role in tumor progression and dissemination, immunosuppression and metabolic support of cancer cells. We have identified increased cancer associated fibroblasts (CAFs) in more metastatic prostate cancers. Here we investigated the influence of hypoxia in modifying fibroblast metabolism and matrix degradation. We characterized metabolic changes triggered by hypoxia in normal prostate fibroblasts and prostate CAFs using magnetic resonance spectroscopy (MRS). We assessed changes in prostate fibroblast invasion and ECM degradation with our MR-compatible cell perfusion system (MR-CPS).
Methods: Experiments were performed using human prostate fibroblasts (WPMY-1, ATCC, Manassas, VA) and human prostate cancer associated fibroblasts (PCAFs, Asterand Bioscience, Detroit, MI). WPMY-1 were derived from stromal cells from the peripheral zone of the histologically normal adult prostate. PCAFs were obtained from an adenocarcinoma of the prostate gland. To induce hypoxia, WPMY-1 cells were incubated for 48h under hypoxic conditions (0% O2). For MRS, cell extracts were obtained using a dual-phase extraction method, and HR-MRS performed and analyzed as previously described. MR-CPS experiments were carried out with WPMY-1 cells plated on ECM chamber under well-oxygenated (70% O2) or hypoxic (1% O2) conditions as previously detailed by us.
Results: Under normoxia, compared with WPMY-1, PCAFs displayed significantly higher levels of glutamine, glutamate, arginine, lactate, myo-inositol, creatine (Cr), phosphocreatine (PCr), choline (cho) and lower levels of phosphocholine (PC). The response to low oxygenation was completely different between WPMY-1 and PCAFs. WPMY-1 responded to hypoxia with increased levels of glutamine, glutamate, myo-inositol, arginine, PCr and glycerophosphocholine (GPC). PCAFs, on the other hand, responded to hypoxia with decreased levels of arginine, PC, Cr, glutamine, glutamate and lactate. Finally, hypoxia triggered a significantly faster degradation of the ECM by prostate fibroblasts early in the course of the experiment, but not at later time points.
Discussion: We found that hypoxia significantly altered the metabolism of both normal and cancer associated fibroblasts. The metabolic profile of WPMY-1 under hypoxia became similar to PCAFs under normoxia. ECM degradation by normal fibroblast increased under hypoxic conditions. Some of the metabolic changes can be related to supporting cancer cell metabolism and creating an immunosuppressive tumor microenvironment. These data suggest that hypoxia plays an important role in the metabolic transformation of fibroblasts to a malignant metabolic phenotype.
Supported by NIH R35 CA209960.
Citation Format: Jesus Pacheco-Torres, Tariq Shah, W. Nathaniel Brennen, Flonne Wildes, Zaver M. Bhujwalla. Effects of hypoxia on normal prostate fibroblast and prostate cancer associated fibroblast metabolism and matrix degradation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2896.
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Affiliation(s)
| | - Tariq Shah
- The Johns Hopkins University School of Medicine, Baltimore, MD
| | | | - Flonne Wildes
- The Johns Hopkins University School of Medicine, Baltimore, MD
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Krishnamachary B, Mironchik Y, Jacob D, Goggins E, Kakkad S, Ofori F, Dore-Savard L, Bharti SK, Wildes F, Penet MF, Black ME, Bhujwalla ZM. Hypoxia theranostics of a human prostate cancer xenograft and the resulting effects on the tumor microenvironment. Neoplasia 2020; 22:679-688. [PMID: 33142234 PMCID: PMC7586064 DOI: 10.1016/j.neo.2020.10.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 10/01/2020] [Accepted: 10/04/2020] [Indexed: 12/22/2022] Open
Abstract
Developed a hypoxia theranostic imaging strategy to eliminate hypoxic cells. Hypoxic cell elimination resulted in fewer cancer associated fibroblasts (CAFs) Collagen 1 fiber patterns were altered with hypoxic cell elimination. cDNA nanoparticles with HRE driven prodrug enzyme expression can target hypoxia.
Hypoxia is frequently observed in human prostate cancer, and is associated with chemoresistance, radioresistance, metastasis, and castrate-resistance. Our purpose in these studies was to perform hypoxia theranostics by combining in vivo hypoxia imaging and hypoxic cancer cell targeting in a human prostate cancer xenograft. This was achieved by engineering PC3 human prostate cancer cells to express luciferase as well as a prodrug enzyme, yeast cytosine deaminase, under control of hypoxic response elements (HREs). Cancer cells display an adaptive response to hypoxia through the activation of several genes mediated by the binding of hypoxia inducible factors (HIFs) to HRE in the promoter region of target gene that results in their increased transcription. HIFs promote key steps in tumorigenesis, including angiogenesis, metabolism, proliferation, metastasis, and differentiation. HRE-driven luciferase expression allowed us to detect hypoxia in vivo to time the administration of the nontoxic prodrug 5-fluorocytosine that was converted by yeast cytosine deaminase, expressed under HRE regulation, to the chemotherapy agent 5-fluorouracil to target hypoxic cells. Conversion of 5-fluorocytosine to 5-fluorouracil was detected in vivo by 19F magnetic resonance spectroscopy. Morphological and immunohistochemical staining and molecular analyses were performed to characterize tumor microenvironment changes in cancer-associated fibroblasts, cell viability, collagen 1 fiber patterns, and HIF-1α. These studies expand our understanding of the effects of eliminating hypoxic cancer cells on the tumor microenvironment and in reducing stromal cell populations such as cancer-associated fibroblasts.
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Affiliation(s)
- Balaji Krishnamachary
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD.
| | - Yelena Mironchik
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Desmond Jacob
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Eibhlin Goggins
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Samata Kakkad
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Francis Ofori
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Louis Dore-Savard
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Santosh Kumar Bharti
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Flonne Wildes
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Marie-France Penet
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD; Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Margaret E Black
- School of Molecular Biosciences, Washington State University, Pullman, WA
| | - Zaver M Bhujwalla
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD; Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD; Radiation Oncology and Molecular Radiation Sciences, The Johns Hopkins University School of Medicine, Baltimore, MD.
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Penet MF, Shah T, Wildes F, Krishnamachary B, Bharti SK, Pacheco-Torres J, Artemov D, Bhujwalla ZM. MRI and MRS of intact perfused cancer cell metabolism, invasion, and stromal cell interactions. NMR Biomed 2019; 32:e4053. [PMID: 30693605 PMCID: PMC6661227 DOI: 10.1002/nbm.4053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 11/15/2018] [Accepted: 11/15/2018] [Indexed: 05/03/2023]
Abstract
Because of the spatial and temporal heterogeneities of cancers, technologies to investigate cancer cells and the consequences of their interactions with abnormal physiological environments, such as hypoxia and acidic extracellular pH, with stromal cells, and with the extracellular matrix, under controlled conditions, are valuable to gain insights into the functioning of cancers. These insights can lead to an understanding of why cancers invade and metastasize, and identify effective treatment strategies. Here we have provided an overview of the applications of MRI/MRS/MRSI to investigate intact perfused cancer cells, their metabolism and invasion, and their interactions with stromal cells and the extracellular matrix.
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Affiliation(s)
- Marie-France Penet
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science
- Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Tariq Shah
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science
| | - Flonne Wildes
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science
| | - Balaji Krishnamachary
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science
| | - Santosh K. Bharti
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science
| | - Jesus Pacheco-Torres
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science
| | - Dmitri Artemov
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science
- Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Zaver M. Bhujwalla
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science
- Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD
- Department of Radiation Oncology and Molecular Radiation Sciences, The Johns Hopkins University School of Medicine, Baltimore, MD
- Correspondence to: Zaver M. Bhujwalla, PhD, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Sciences, The Johns Hopkins University School of Medicine, 720 Rutland Avenue, Rm 208C Traylor Building, Baltimore, MD 21205, USA, Phone: +1 (410) 955 9698 | Fax: +1 (410) 614 1948,
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Pacheco-Torres J, Shah T, Wildes F, Krishnamachary B, Bhujwalla ZM. Abstract 5261: Choline kinase downregulation decreases prostate cancer associated fibroblast viability. Cancer Res 2019. [DOI: 10.1158/1538-7445.am2019-5261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Introduction
We previously observed an increase of prostate CAFs (PCAFs) in prostate cancers that metastasize, consistent with the known role of fibroblasts in inducing growth, confer castration-resistance and increasing metastatic potential. While aberrant choline metabolism has been identified in prostate cancer cells, choline metabolism in fibroblasts and PCAFs is unexplored and may identify a treatment strategy through downregulation of enzymes such as choline kinase alpha (Chk-α), the enzyme that converts choline to phosphocholine (PC). Chk-α is typically increased in cancer cells. Here we characterized the metabolic profile of normal prostate fibroblasts and PCAFs as well as determined the effect of Chk-α downregulation with small interfering RNA (siRNA).
Methods
Experiments were performed using the human prostate myofibroblasts (WPMY-1, derived from stromal cells from the peripheral zone of the histologically normal adult prostate) and PCAFs (obtained from an adenocarcinoma of the prostate gland). Cell extracts were obtained using a dual-phase extraction method. High-resolution 1H MR spectra were recorded on a Bruker Biospin Avance-III 750 MHz NMR (Bruker Biospin) spectrometer operating at a 1H frequency of 750.21 MHz using a 5-mm broad band inverse (BBI) probe head equipped with z-gradient accessories. 1H MR spectra were manually phased and automated baseline corrected using TOPSPIN 3.2 software. Integrals of the metabolites of interest were determined and normalized to the TSP reference and the number of cells. Metabolites were estimated from at least three experimental samples. Statistical significance was evaluated using the Student’s t-test. To target Chk-α, cells were transiently transfected with small interfering RNA (siRNA) against Chk-α at a concentration of 100 nM for 48h using standard protocol. Total RNA was isolated, complementary cDNA synthesized and quantitative real-time PCR performed using IQ SYBR Green supermix and gene specific primers. Viability studies were performed using CCK8 assay as previously reported.
Results and Discussion
Metabolic profiles were significantly different between WPMY-1 and PCAFs, with significant differences in choline, phosphocholine, glutamate and alanine, among others. siRNA directed against Chk-α reduced mRNA levels in both WPMY-1 and PCAFs. We observed a significant decrease of cell viability in PCAFs but not in normal prostate fibroblasts. These data support investigating Chk-α as a target to eliminate CAFs in tumors. Increased glutamate observed in PCAFs also support targeting enzymes and transporters in glutamine/glutamate metabolism as potential therapeutic strategies against PCAFs. Future studies with CAFs from different cancers should further validate the metabolic differences between normal fibroblasts and CAFs identified in this study.
Supported by NIH R35CA209960. JPT is supported by Martin-Escudero Foundation.
Citation Format: Jesus Pacheco-Torres, Tariq Shah, Flonne Wildes, Balaji Krishnamachary, Zaver M. Bhujwalla. Choline kinase downregulation decreases prostate cancer associated fibroblast viability [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 5261.
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Affiliation(s)
| | - Tariq Shah
- The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Flonne Wildes
- The Johns Hopkins University School of Medicine, Baltimore, MD
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Jin J, Barnett J, Wildes F, Nimaggada S, Bhujwalla Z. Abstract 3640: Cancer cell membrane coated biomimetic nanoparticles as decoys for disrupting cancer cell-stromal cell interactions. Cancer Res 2019. [DOI: 10.1158/1538-7445.am2019-3640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Introduction: Biomimetic nanoparticles (NPs) combining synthetic and biological materials have flexibility and functionality for disruptive strategies.1 Stromal cells such as cancer associated fibroblasts (CAFs) mediate many of the aggressive characteristics of cancer and play a crucial role in proliferation, invasiveness, metastasis, and angiogenesis of cancer.2 NPs coated with cancer cell membrane fractions (CCMFs) inherit the repertoire of surface proteins from cancer cells, making them potentially useful as decoys to disrupt cancer cell-stromal cell interactions. Here, we coated cancer cell membranes onto poly(lactic-co-glycolic acid) (PLGA) NPs to form CCMF-PLGA NPs, and characterized their protein profile, size, purity, cellular internalization, and integrity. We investigated, for the first time, the ability of these “artificial cancer cells” to disrupt fibroblast-mediated migration and lung metastasis.
Method: CCMFs were isolated upon cell homogenization, and sucrose density gradient centrifugation. PLGA NPs were prepared by nanoprecipitation. CCMFs and PLGA NPs were mixed and physically extruded through a porous membrane to obtain CCMF-PLGA NPs. The protein profile of CCMFs was analyzed by western blot with antibodies against cell fraction markers.. The experimental lung metastasis model was established by intravenously injecting MDA-MD-231 cells constitutively expressing luciferase (231-luc) through the tail vein of nude mice. The treated group was inoculated with the same number of 231-luc cells mixed with CCMFs-PLGA NPs and injected weekly with CCMF-PLGA NPs in the following weeks. Lung metastasis was monitored in vivo for three consecutive weeks by bioluminescence imaging (BLI). At the end of treatment, lungs were isolated and inflated. Metastatic nodules were imaged with BLI and examined by histology.
Results: Plasma membrane purity was confirmed from western blot analysis that showed the significant enrichment of Na+/K+-ATPase, negligible amount of GPR78 or GAPDH in CCMFs. Confocal fluorescence microscopy and flow cytometry confirmed a “right-side” out orientation of CCMF-PLGA NPs and the integrity of membrane-associated proteins after membrane isolation and PLGA coating. When CCMFs or CCMF-PLGA NPs were added to HMFs in the transwell assay, fewer cancer cells migrated towards HMFs, identifying the unique ability of CCMF-PLGA NPs to disrupt HMF-cancer cell interactions. In the lung metastasis study, mice treated with CCMF-PLGA NPs had significantly less incidence and metastatic burden confirmed by BLI and histology. CCMF-PLGA NPs hold promise as decoys to disrupt cancer cell-stromal cell interactions.
References: 1. Fang, R. et al. Small 2015; 2. Shiga, K. et al. Cancers 2015. Supported by NIH R21 CA198243, R35 CA209960, and a grant from the Emerson Collective.
Citation Format: Jiefu Jin, James Barnett, Flonne Wildes, Sridhar Nimaggada, Zaver Bhujwalla. Cancer cell membrane coated biomimetic nanoparticles as decoys for disrupting cancer cell-stromal cell interactions [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3640.
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Affiliation(s)
- Jiefu Jin
- Johns Hopkins Univ. School of Medicine, Baltimore, MD
| | - James Barnett
- Johns Hopkins Univ. School of Medicine, Baltimore, MD
| | - Flonne Wildes
- Johns Hopkins Univ. School of Medicine, Baltimore, MD
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Jin J, Krishnamachary B, Barnett JD, Chatterjee S, Chang D, Mironchik Y, Wildes F, Jaffee EM, Nimmagadda S, Bhujwalla ZM. Human Cancer Cell Membrane-Coated Biomimetic Nanoparticles Reduce Fibroblast-Mediated Invasion and Metastasis and Induce T-Cells. ACS Appl Mater Interfaces 2019; 11:7850-7861. [PMID: 30707559 PMCID: PMC6628902 DOI: 10.1021/acsami.8b22309] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/14/2023]
Abstract
Biomimetic nanoparticles (NPs) combine the flexibility and reproducibility of synthetic materials with the functionality of biological materials. Here, we developed and characterized biomimetic poly(lactic- co-glycolic acid) (PLGA) NPs coated with human cancer cell membrane fractions (CCMFs) to form CCMF-coated PLGA (CCMF-PLGA) NPs. We evaluated the ability of these CCMF-PLGA NPs to disrupt cancer cell-stromal cell interactions and to induce an immune response. Western blot analysis verified the plasma membrane purity of CCMFs. Confocal fluorescence microscopy and flow cytometry confirmed the presence of intact membrane-associated proteins including CXCR4 and CD44 following membrane derivation and coating. CCMFs and CCMF-PLGA NPs were capable of inhibiting cancer cell migration toward human mammary fibroblasts. Intravenous injection of CCMF-PLGA NPs significantly reduced experimental metastasis in vivo. Following immunization of Balb/c mice, near-infrared fluorescence imaging confirmed the migration of NPs to proximal draining lymph nodes (LNs). A higher percentage of CD8+ and CD4+ cytotoxic T-lymphocyte populations was observed in spleens and LNs of CCMF-PLGA NP-immunized mice. Splenocytes isolated from CCMF-PLGA NP-immunized mice had the highest number of interferon gamma-producing T-cells as detected by the ELISpot assay. CCMF-PLGA NPs hold promise for disrupting cancer cell-stromal cell interactions and for priming the immune system in cancer immunotherapy.
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Affiliation(s)
- Jiefu Jin
- Division of Cancer Imaging Research, The Russell H Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Correspondence should be addressed to: (ZMB); (JJ)
| | - Balaji Krishnamachary
- Division of Cancer Imaging Research, The Russell H Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - James D. Barnett
- Division of Cancer Imaging Research, The Russell H Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Samit Chatterjee
- Division of Cancer Imaging Research, The Russell H Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Di Chang
- Division of Cancer Imaging Research, The Russell H Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Yelena Mironchik
- Division of Cancer Imaging Research, The Russell H Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Flonne Wildes
- Division of Cancer Imaging Research, The Russell H Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Elizabeth M. Jaffee
- Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Department of Pathology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Sridhar Nimmagadda
- Division of Cancer Imaging Research, The Russell H Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Zaver M. Bhujwalla
- Division of Cancer Imaging Research, The Russell H Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Department of Radiation Oncology and Molecular Radiation Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Correspondence should be addressed to: (ZMB); (JJ)
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Shah T, Krishnamachary B, Wildes F, Wijnen JP, Glunde K, Bhujwalla ZM. Molecular causes of elevated phosphoethanolamine in breast and pancreatic cancer cells. NMR Biomed 2018; 31:e3936. [PMID: 29928787 PMCID: PMC6118328 DOI: 10.1002/nbm.3936] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 04/05/2018] [Accepted: 04/06/2018] [Indexed: 05/03/2023]
Abstract
Elevated phosphoethanolamine (PE) is frequently observed in MRS studies of human cancers and xenografts. The role of PE in cell survival and the molecular causes underlying this increase are, however, relatively underexplored. In this study, we investigated the roles of ethanolamine kinases (Etnk-1 and 2) and choline kinases (Chk-α and β) in contributing to increased PE in human breast and pancreatic cancer cells. We investigated the effect of silencing Etnk-1 and Etnk-2 on cell viability as a potential therapeutic strategy. Both breast and pancreatic cancer cells showed higher PE compared with their nonmalignant counterparts. We identified Etnk-1 as a major cause of the elevated PE levels in these cancer cells, with little or no contribution from Chk-α, Chk-β, or Etnk-2. The increase of PE observed in pancreatic cancer cells in culture was replicated in the corresponding tumor xenografts. Downregulation of Etnk-1 with siRNA resulted in cell cytotoxicity that correlated with PE levels in breast and pancreatic cancer cells. Etnk-1 may provide a potential therapeutic target in breast and pancreatic cancers.
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Affiliation(s)
- Tariq Shah
- Division of Cancer Imaging Research, The Russell H Morgan Department of Radiology and Radiological Science, The Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Balaji Krishnamachary
- Division of Cancer Imaging Research, The Russell H Morgan Department of Radiology and Radiological Science, The Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Flonne Wildes
- Division of Cancer Imaging Research, The Russell H Morgan Department of Radiology and Radiological Science, The Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Jannie P. Wijnen
- Division of Cancer Imaging Research, The Russell H Morgan Department of Radiology and Radiological Science, The Johns Hopkins University, School of Medicine, Baltimore, MD, USA
- Centre of Image Sciences/High field MR Research group, Radiology, University Medical Centre Utrecht, Utrecht, the Netherlands
| | - Kristine Glunde
- Division of Cancer Imaging Research, The Russell H Morgan Department of Radiology and Radiological Science, The Johns Hopkins University, School of Medicine, Baltimore, MD, USA
- Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Zaver M. Bhujwalla
- Division of Cancer Imaging Research, The Russell H Morgan Department of Radiology and Radiological Science, The Johns Hopkins University, School of Medicine, Baltimore, MD, USA
- Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University, School of Medicine, Baltimore, MD, USA
- Department of Radiation Oncology and Molecular Radiation Sciences, The Johns Hopkins University, School of Medicine, Baltimore, MD, USA
- Correspondence: Zaver M. Bhujwalla, PhD, Division of Cancer Imaging Research, Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, 720 Rutland Avenue, Rm 208C Traylor Building, Baltimore, MD 21205, USA, Phone: +1 (410) 955 9698 | Fax: +1 (410) 614 1948,
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10
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Bharti SK, Mironchik Y, Wildes F, Penet MF, Goggins E, Krishnamachary B, Bhujwalla ZM. Metabolic consequences of HIF silencing in a triple negative human breast cancer xenograft. Oncotarget 2018; 9:15326-15339. [PMID: 29632647 PMCID: PMC5880607 DOI: 10.18632/oncotarget.24569] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Accepted: 02/20/2018] [Indexed: 02/06/2023] Open
Abstract
Hypoxia is frequently encountered in tumors and results in the stabilization of hypoxia inducible factors (HIFs). These factors transcriptionally activate genes that allow cells to adapt to hypoxia. In cancers, hypoxia and HIFs have been associated with increased invasion, metastasis, and resistance to chemo and radiation therapy. Here we have characterized the metabolic consequences of silencing HIF-1α and HIF-2α singly or combined in MDA-MB-231 triple negative human breast cancer xenografts, using non-invasive proton magnetic resonance spectroscopic imaging (1H MRSI) of in vivo tumors, and high-resolution 1H MRS of tumor extracts. Tumors from all three sublines showed a significant reduction of growth rate. We identified new metabolic targets of HIF, and demonstrated the divergent consequences of silencing HIF-1α and HIF-2α individually on some of these targets. These data expand our understanding of the metabolic pathways regulated by HIFs that may provide new insights into the adaptive metabolic response of cancer cells to hypoxia. Such insights may lead to novel metabolism based therapeutic targets for triple negative breast cancer.
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Affiliation(s)
- Santosh K Bharti
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, School of Medicine, The Johns Hopkins University, Baltimore, MD, USA
| | - Yelena Mironchik
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, School of Medicine, The Johns Hopkins University, Baltimore, MD, USA
| | - Flonne Wildes
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, School of Medicine, The Johns Hopkins University, Baltimore, MD, USA
| | - Marie-France Penet
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, School of Medicine, The Johns Hopkins University, Baltimore, MD, USA.,Sidney Kimmel Comprehensive Cancer Center, School of Medicine, The Johns Hopkins University, Baltimore, MD, USA
| | - Eibhlin Goggins
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, School of Medicine, The Johns Hopkins University, Baltimore, MD, USA
| | - Balaji Krishnamachary
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, School of Medicine, The Johns Hopkins University, Baltimore, MD, USA
| | - Zaver M Bhujwalla
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, School of Medicine, The Johns Hopkins University, Baltimore, MD, USA.,Sidney Kimmel Comprehensive Cancer Center, School of Medicine, The Johns Hopkins University, Baltimore, MD, USA.,Department of Radiation Oncology and Molecular Radiation Sciences, School of Medicine, The Johns Hopkins University, Baltimore, MD, USA
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11
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Goggins E, Kakkad S, Mironchik Y, Jacob D, Wildes F, Krishnamachary B, Bhujwalla ZM. Hypoxia Inducible Factors Modify Collagen I Fibers in MDA-MB-231 Triple Negative Breast Cancer Xenografts. Neoplasia 2017; 20:131-139. [PMID: 29247885 PMCID: PMC5884039 DOI: 10.1016/j.neo.2017.11.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Revised: 11/18/2017] [Accepted: 11/20/2017] [Indexed: 12/14/2022] Open
Abstract
Hypoxia inducible factors (HIFs) are transcription factors that mediate the response of cells to hypoxia. HIFs have wide-ranging effects on metabolism, the tumor microenvironment (TME) and the extracellular matrix (ECM). Here we investigated the silencing effects of two of the three known isoforms, HIF-1α and HIF-2α, on collagen 1 (Col1) fibers, which form a major component of the ECM of tumors. Using a loss-of-function approach for HIF-1α or 2α or both HIF-1α and 2α, we identified a relationship between HIFs and Col1 fibers in MDA-MB-231 tumors. Tumors derived from MDA-MB-231 cells with HIF-1α or 2α or both HIF-1α and 2α silenced contained higher percent fiber volume and lower inter-fiber distance compared to tumors derived from empty vector MDA-MB-231 cells. Depending upon the type of silencing, we observed changes in Col1 degrading enzymes, and enzymes involved in Col1 synthesis and deposition. Additionally, a reduction in lysyl oxidase protein expression in HIF-down-regulated tumors suggests that more non-cross-linked fibers were present. Collectively these results identify the role of HIFs in modifying the ECM and the TME and provide new insights into the effects of hypoxia on the tumor ECM.
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Affiliation(s)
- Eibhlin Goggins
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Chemistry, Georgetown University, 37th and O Streets NW, Washington, D.C. 20057, USA
| | - Samata Kakkad
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Yelena Mironchik
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Desmond Jacob
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Flonne Wildes
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Balaji Krishnamachary
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
| | - Zaver M Bhujwalla
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA; Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University, School of Medicine, Baltimore, MD, USA.
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12
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Krishnamachary B, Stasinopoulos I, Kakkad S, Penet MF, Jacob D, Wildes F, Mironchik Y, Pathak AP, Solaiyappan M, Bhujwalla ZM. Breast cancer cell cyclooxygenase-2 expression alters extracellular matrix structure and function and numbers of cancer associated fibroblasts. Oncotarget 2017; 8:17981-17994. [PMID: 28152501 PMCID: PMC5392301 DOI: 10.18632/oncotarget.14912] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 12/27/2016] [Indexed: 01/21/2023] Open
Abstract
Cyclooxygenase-2 (COX-2) is a critically important mediator of inflammation that significantly influences tumor angiogenesis, invasion, and metastasis. We investigated the role of COX-2 expressed by triple negative breast cancer cells in altering the structure and function of the extracellular matrix (ECM). COX-2 downregulation effects on ECM structure and function were investigated using magnetic resonance imaging (MRI) and second harmonic generation (SHG) microscopy of tumors derived from triple negative MDA-MB-231 breast cancer cells, and a derived clone stably expressing a short hairpin (shRNA) molecule downregulating COX-2. MRI of albumin-GdDTPA was used to characterize macromolecular fluid transport in vivo and SHG microscopy was used to quantify collagen 1 (Col1) fiber morphology. COX-2 downregulation decreased Col1 fiber density and altered macromolecular fluid transport. Immunohistochemistry identified significantly fewer activated cancer associated fibroblasts (CAFs) in low COX-2 expressing tumors. Metastatic lung nodules established by COX-2 downregulated cells were infrequent, smaller, and contained fewer Col1 fibers.COX-2 overexpression studies were performed with tumors derived from triple negative SUM-149 breast cancer cells lentivirally transduced to overexpress COX-2. SHG microscopy identified significantly higher Col1 fiber density in COX-2 overexpressing tumors with an increase of CAFs. These data expand upon the roles of COX-2 in shaping the structure and function of the ECM in primary and metastatic tumors, and identify the potential role of COX-2 in modifying the number of CAFs in tumors that may have contributed to the altered ECM.
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Affiliation(s)
- Balaji Krishnamachary
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD 21205, USA
| | - Ioannis Stasinopoulos
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD 21205, USA
| | - Samata Kakkad
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD 21205, USA
| | - Marie-France Penet
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD 21205, USA.,Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Desmond Jacob
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD 21205, USA
| | - Flonne Wildes
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD 21205, USA
| | - Yelena Mironchik
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD 21205, USA
| | - Arvind P Pathak
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD 21205, USA.,Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Meiyappan Solaiyappan
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD 21205, USA
| | - Zaver M Bhujwalla
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD 21205, USA.,Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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13
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Shah T, Wildes F, Artemov D, Bhujwalla ZM. Abstract 4335: The role of fibroblasts in prostate cancer cell invasion in tumor microenvironments. Cancer Res 2017. [DOI: 10.1158/1538-7445.am2017-4335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Cancer-associated fibroblasts (CAFs) play a critical role in tumor aggressiveness. We have started to investigate the role of CAFs in different tumor microenvironments of hypoxia and acidic extracellular pH. To further understand interactions between CAFs and cancer cells under carefully controlled conditions of hypoxia and acidic pH, we have used our MR compatible cell perfusion system to determine, for the first time, changes in the ability of prostate cancer cells to invade and degrade the extracellular matrix (ECM) in the presence of prostate myofibroblasts.
Experiments were performed using the human prostate cancer cell lines PC-3 and prostate myofibroblasts (WPMY-1, ATCC, Manassas, VA). Before each MR experiment, 2.5X106 PC-3 cells were seeded on 0.5 ml of Plastic Plus beads in five 100mm dishes and grown for 4 days. Experiments were carried out with PC-3 cells plated on an ECM chamber with or without prostate myofibroblasts layered between the PC-3 and the ECM. For experiments investigating prostate myofibroblasts-cancer cell interaction, 5 X 104 prostate myofibroblasts were seeded on ECM gel contained in a chamber overnight before the MR experiment. This time interval allowed myofibroblasts to attach to the ECM gel. Degradation of ECM by cancer cells was determined at the 24h time point relative to the initial time point from the proton images. MR data were acquired on a 9.4 T MR spectrometer every 12 h over a period of 2 days. T1-weighted 1H MR imaging was performed to evaluate changes in ECM invasion and degradation. The extent of ECM degradation was estimated by drawing a region of interest (ROI) around the ECM gel region using NIH ImageJ software. The degradation index was defined as (ROIt=0-ROIt=24)/ROIt=0. One-dimensional 1H MR profiles of intracellular water were acquired along the length (z-axis) of the sample by diffusion- weighted MRI. These profiles were used to derive an invasion index by quantifying the number of cells invading into the ECM.
Fibroblasts alone marginally degraded the matrigel. PC-3 cells, being invasive cells also degraded the ECM. However, ECM degradation increased when prostate myofibroblasts were layered between the ECM and the PC-3 prostate cancer cells. Consistent with the degradation data, PC-3 cells showed a significant increase in the invasive index in the presence of myofibroblasts under normoxia. The enhanced invasion and degradation of ECM by PC-3 cells in the presence of myofibroblasts suggests that the interaction between myofibroblasts and PC-3 cells plays a role in prostate cancer invasion. Further studies with hypoxia and acidic pH microenvironment are currently ongoing.
Citation Format: Tariq Shah, Flonne Wildes, Dmitri Artemov, Zaver M. Bhujwalla. The role of fibroblasts in prostate cancer cell invasion in tumor microenvironments [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4335. doi:10.1158/1538-7445.AM2017-4335
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Affiliation(s)
- Tariq Shah
- Johns Hopkins Univ. School of Medicine, Baltimore, MD
| | - Flonne Wildes
- Johns Hopkins Univ. School of Medicine, Baltimore, MD
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14
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Bharti S, Wildes F, Hung CF, Wu TC, Bhujwalla Z, Penet MF. Abstract 2505: High-resolution MRS characterization of malignant ascites in two models of ovarian cancer. Cancer Res 2017. [DOI: 10.1158/1538-7445.am2017-2505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Build-up of malignant ascites occurs in more than one third of ovarian cancer patients and significantly contributes to poor quality of life and mortality. Advances in understanding malignant ascites formation and finding new therapeutic options are urgently needed. High-resolution 1H MRS has been described as extremely useful in detecting endogenous metabolites to diagnose cancer, by providing a detailed overview of metabolic pathways in a single measurement. In the present study, we are using two ovarian cancer cell lines, the murine ID8-VEGF-Defb29 cell line and the human OVCAR3 cell line. Implanted orthotopically, these two ovarian cancer models are characterized by different profile of ascites formation. The mouse cell line ID8-VEGF-Defb29 induces large volumes of ascites, often more than 10 mL, while the human OVCAR3 cell line induces ascites less frequently and at smaller volumes, usually less than 0.2 mL. We applied high-resolution 1H MRS to compare the metabolic composition of both ascitic fluids. To better understand the differences observed, we characterized the metabolism of these ovarian cancer cells in culture by analyzing cell lysates and conditioned culture media with 1H MRS to advance our understanding of cancer cell metabolic reprogramming in malignant ascites formation and the role of the tumor microenvironment in ascites formation and composition. The two tumor models used in this study induced different ascitic profiles. While OVCAR3 tumor bearing mice developed small viscous volume of ascites, ID8-VEGF-Defb29 induced higher volumes. ID8-VEGF-Defb29 ascitic fluids were characterized by higher levels of glutamine, glucose, poly-unsaturated fatty acids and pyruvate compared to the OVCAR3 fluids, while all the other metabolites, including glutamate, lactate, myo-inositol, choline and acetate, were lower. To determine if the differences observed in the ascitic fluids were only due to a different metabolism of the cancer cells, we investigated their metabolism in vitro. We analyzed the metabolites present in the conditioned cell culture media, and in the cells, and observed differences in OVCAR3 and ID8-VEGF-Defb29 cells metabolism in vitro, without replicating the differences observed in vitro. A Venn diagram of the different metabolites present in the cells, media and ascites showed differences in the metabolites present in those 3 compartments, and highlighted the ones in common. Beta-hydroxybutyrate, lipids, maleic and citrate were found in both ascites, and not in the cells or media. Ascites MRS derived biomarkers could help in ovarian cancer diagnosis, and enhance our understanding of the biochemical and metabolic changes associated with ovarian cancer, and with ascites formation.
Supported by Tina’s Wish Foundation, NIH P50CA013175 and P30CA06973.
Citation Format: Santosh Bharti, Flonne Wildes, Chien-Fu Hung, TC Wu, Zaver Bhujwalla, Marie-France Penet. High-resolution MRS characterization of malignant ascites in two models of ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2505. doi:10.1158/1538-7445.AM2017-2505
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Affiliation(s)
- Santosh Bharti
- 1JHU ICMIC Program, Division of Cancer Imaging Research, Department of Radiology, Johns Hopkins Univ. School of Medicine, Baltimore, MD
| | - Flonne Wildes
- 1JHU ICMIC Program, Division of Cancer Imaging Research, Department of Radiology, Johns Hopkins Univ. School of Medicine, Baltimore, MD
| | - Chien-Fu Hung
- 2Department of Pathology, Johns Hopkins Univ. School of Medicine, Baltimore, MD
| | - TC Wu
- 2Department of Pathology, Johns Hopkins Univ. School of Medicine, Baltimore, MD
| | - Zaver Bhujwalla
- 1JHU ICMIC Program, Division of Cancer Imaging Research, Department of Radiology, Johns Hopkins Univ. School of Medicine, Baltimore, MD
| | - Marie-France Penet
- 1JHU ICMIC Program, Division of Cancer Imaging Research, Department of Radiology, Johns Hopkins Univ. School of Medicine, Baltimore, MD
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15
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Penet MF, Krishnamachary B, Wildes F, Mironchik Y, Mezzanzanica D, Podo F, de Reggi M, Gharib B, Bhujwalla ZM. Effect of Pantethine on Ovarian Tumor Progression and Choline Metabolism. Front Oncol 2016; 6:244. [PMID: 27900284 PMCID: PMC5110532 DOI: 10.3389/fonc.2016.00244] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Accepted: 11/02/2016] [Indexed: 01/21/2023] Open
Abstract
Epithelial ovarian cancer remains the leading cause of death from gynecologic malignancy among women in developed countries. New therapeutic strategies evaluated with relevant preclinical models are urgently needed to improve survival rates. Here, we have assessed the effect of pantethine on tumor growth and metabolism using magnetic resonance imaging and high-resolution proton magnetic resonance spectroscopy (MRS) in a model of ovarian cancer. To evaluate treatment strategies, it is important to use models that closely mimic tumor growth in humans. Therefore, we used an orthotopic model of ovarian cancer where a piece of tumor tissue, derived from an ovarian tumor xenograft, is engrafted directly onto the ovary of female mice, to maintain the tumor physiological environment. Treatment with pantethine, the precursor of vitamin B5 and active moiety of coenzyme A, was started when tumors were ~100 mm3 and consisted of a daily i.p. injection of 750 mg/kg in saline. Under these conditions, no side effects were observed. High-resolution 1H MRS was performed on treated and control tumor extracts. A dual-phase extraction method based on methanol/chloroform/water was used to obtain lipid and water-soluble fractions from the tumors. We also investigated effects on metastases and ascites formation. Pantethine treatment resulted in slower tumor progression, decreased levels of phosphocholine and phosphatidylcholine, and reduced metastases and ascites occurrence. In conclusion, pantethine represents a novel potential, well-tolerated, therapeutic tool in patients with ovarian cancer. Further in vivo preclinical studies are needed to confirm the beneficial role of pantethine and to better understand its mechanism of action.
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Affiliation(s)
- Marie-France Penet
- JHU ICMIC Program, Russell H. Morgan, Division of Cancer Imaging Research, Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA; Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Balaji Krishnamachary
- JHU ICMIC Program, Russell H. Morgan, Division of Cancer Imaging Research, Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine , Baltimore, MD , USA
| | - Flonne Wildes
- JHU ICMIC Program, Russell H. Morgan, Division of Cancer Imaging Research, Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine , Baltimore, MD , USA
| | - Yelena Mironchik
- JHU ICMIC Program, Russell H. Morgan, Division of Cancer Imaging Research, Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine , Baltimore, MD , USA
| | - Delia Mezzanzanica
- Unit of Molecular Therapies, Department of Experimental Oncology and Molecular Medicine, Fondazione IRCCS Istituto Nazionale dei Tumori , Milan , Italy
| | - Franca Podo
- Section of Molecular and Cellular Imaging, Department of Cell Biology and Neurosciences, Istituto Superiore di Sanità , Rome , Italy
| | - Max de Reggi
- Neurobiology of Cellular Interactions and Neurophysiopathology (NICN), Aix Marseille Univ, CNRS , Marseille , France
| | - Bouchra Gharib
- Neurobiology of Cellular Interactions and Neurophysiopathology (NICN), Aix Marseille Univ, CNRS , Marseille , France
| | - Zaver M Bhujwalla
- JHU ICMIC Program, Russell H. Morgan, Division of Cancer Imaging Research, Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA; Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
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16
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Shah T, Krishnamachary B, Wildes F, Mironchik Y, Kakkad SM, Jacob D, Artemov D, Bhujwalla ZM. HIF isoforms have divergent effects on invasion, metastasis, metabolism and formation of lipid droplets. Oncotarget 2016; 6:28104-19. [PMID: 26305551 PMCID: PMC4695047 DOI: 10.18632/oncotarget.4612] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Accepted: 07/08/2015] [Indexed: 12/17/2022] Open
Abstract
Cancer cells adapt to hypoxia by the stabilization of hypoxia inducible factor (HIF)-α isoforms that increase the transcription of several genes. Among the genes regulated by HIF are enzymes that play a role in invasion, metastasis and metabolism. We engineered triple (estrogen receptor/progesterone receptor/HER2/neu) negative, invasive MDA-MB-231 and SUM149 human breast cancer cells to silence the expression of HIF-1α, HIF-2α or both isoforms of HIF-α. We determined the metabolic consequences of HIF silencing and the ability of HIF-α silenced cells to invade and degrade the extracellular matrix (ECM) under carefully controlled normoxic and hypoxic conditions. We found that silencing HIF-1α alone was not sufficient to attenuate invasiveness in both MDA-MB-231 and SUM149 cell lines. Significantly reduced metastatic burden was observed in single (HIF-1α or HIF-2α) and double α-isoform silenced cells, with the reduction most evident when both HIF-1α and HIF-2α were silenced in MDA-MB-231 cells. HIF-2α played a major role in altering cell metabolism. Lipids and lipid droplets were significantly reduced in HIF-2α and double silenced MDA-MB-231 and SUM149 cells, implicating HIF in their regulation. In addition, lactate production and glucose consumption were reduced. These results suggest that in vivo, cells in or near hypoxic regions are likely to be more invasive. The data indicate that targeting HIF-1α alone is not sufficient to attenuate invasiveness, and that both HIF-1α and HIF-2α play a role in the metastatic cascade in these two cell lines.
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Affiliation(s)
- Tariq Shah
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD, USA
| | - Balaji Krishnamachary
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD, USA
| | - Flonne Wildes
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD, USA
| | - Yelena Mironchik
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD, USA
| | - Samata M Kakkad
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD, USA
| | - Desmond Jacob
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD, USA
| | - Dmitri Artemov
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD, USA.,Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Zaver M Bhujwalla
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD, USA.,Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
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17
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Krishnamachary B, Dore-Savard L, Bharti SK, Wildes F, Mironchik Y, Black ME, Bhujwalla ZM. Abstract 4228: Imaging and targeting of hypoxic microenvironments in prostate cancer. Cancer Res 2016. [DOI: 10.1158/1538-7445.am2016-4228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Cancer cells display an adaptive response to hypoxia through the activation of several genes mediated by the binding of hypoxia inducible factors (HIFs) to hypoxia response elements (HRE) in the promoter region of target gene that results in their increased transcription [1]. HIFs promote key steps in tumorigenesis, including angiogenesis, metabolism, proliferation, metastasis, and differentiation [1]. Bacterial or yeast cytosine deaminase (yCD) converts the nontoxic prodrug 5-fluorocytosine (5-FC) to the anti-cancer drug 5-fluorouracil (5-FU) that is widely used in cancer treatment [2]. Using a lentivirus approach, we established controlled expression of yCD by HRE in prostate cancer cells (PC-3). These cells also report on HIF-1α expression with regulated luciferase (Luc) expression, allowing detection of hypoxia, and the generation of 5-FU from 5-FC by yCD in the presence of hypoxia. Transduction efficiency and reporter activity in response to hypoxia was evaluated by performing luciferase assays, and bioluminescence imaging (BLI) of cells in vitro or in vivo using a Xenogen IVIS Spectrum system. Cell viability in vitro in response to hypoxia in the presence of 5-FC was assessed by MTS assay. In vivo studies were performed by inoculating 2×10⁁6 PC-3-HRE-Luc cells and PC-3-HRE-yCD+Luc cells on either flank of 5-week-old male severely combined immune deficient (SCID) mice. BLI was performed once tumors reached ∼200mm3 followed by 5-FC injection through the tail vein (200mg/kg) and intraperitoneally (250mg/kg). BLI was performed 3 days after the first 5-FC injection and continued through the treatment protocol. At the end of the treatment protocol, tumors were excised, and a part of the tumor was processed for immunohistochemistry. Bioluminescence was detected in both PC3-HRE-Luc and PC-3-HRE-yCD+Luc cells only in response to the hypoxia mimetic cobalt chloride or hypoxia (1% O2) confirming the regulation of luciferase by hypoxia and activation of CD. Expression of yCD and its ability to convert the prodrug 5-FC to 5-FU, with increased cell kill was evident under hypoxia. In vivo, engineered PC-3-HRE-yCD+Luc cells reported hypoxia, and showed significant reduction of hypoxic regions and tumor volume. Morphologically, PC-3-HRE-yCD+Luc tumors exhibited extensive necrosis. We are currently evaluating the effects of eliminating hypoxic cancer cells on distant metastasis as well as on aggressive subpopulations such as cancer stem cells in the primary tumor.
References: [1] Philip, B., et al., Carcinogenesis, 2013. 34(8):1699-707.,[2] Longley DB, et al., Nat Rev Cancer, 2003. 3: 330-38.
Acknowledgements: This work was supported by NIH R01CA136576 and P50 CA103175. We thank Mr. Gary Cromwell for technical assistance
Citation Format: Balaji Krishnamachary, Louis Dore-Savard, Santosh Kumar Bharti, Flonne Wildes, Yelena Mironchik, Margaret E. Black, Zaver M. Bhujwalla. Imaging and targeting of hypoxic microenvironments in prostate cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4228.
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Shah T, Wildes F, Kakkad S, Artemov D, Bhujwalla ZM. Lymphatic endothelial cells actively regulate prostate cancer cell invasion. NMR Biomed 2016; 29:904-911. [PMID: 27149683 DOI: 10.1002/nbm.3543] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 03/23/2016] [Accepted: 03/29/2016] [Indexed: 06/05/2023]
Abstract
Lymphatic vessels serve as the primary route for metastatic spread to lymph nodes. However, it is not clear how interactions between cancer cells and lymphatic endothelial cells (LECs), especially within hypoxic microenvironments, affect the invasion of cancer cells. Here, using an MR compatible cell perfusion assay, we investigated the role of LEC-prostate cancer (PCa) cell interaction in the invasion and degradation of the extracellular matrix (ECM) by two human PCa cell lines, PC-3 and DU-145, under normoxia and hypoxia, and determined the metabolic changes that occurred under these conditions. We observed a significant increase in the invasion of ECM by invasive PC-3 cells, but not poorly invasive DU-145 cells when human dermal lymphatic microvascular endothelial cells (HMVEC-dlys) were present. Enhanced degradation of ECM by PC-3 cells in the presence of HMVEC-dlys identified interactions between HMVEC-dlys and PCa cells influencing cancer cell invasion. The enhanced ECM degradation was partly attributed to increased MMP-9 enzymatic activity in PC-3 cells when HMVEC-dlys were in close proximity. Significantly higher uPAR and MMP-9 expression levels observed in PC-3 cells compared to DU-145 cells may be one mechanism for increased invasion and degradation of matrigel by these cells irrespective of the presence of HMVEC-dlys. Hypoxia significantly decreased invasion by PC-3 cells, but this decrease was significantly attenuated when HMVEC-dlys were present. Significantly higher phosphocholine was observed in invasive PC-3 cells, while higher glycerophosphocholine was observed in DU-145 cells. These metabolites were not altered in the presence of HMVEC-dlys. Significantly increased lipid levels and lipid droplets were observed in PC-3 and DU-145 cells under hypoxia reflecting an adaptive survival response to oxidative stress. These results suggest that in vivo, invasive cells in or near lymphatic endothelial cells are likely to be more invasive and degrade the ECM to influence the metastatic cascade. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Tariq Shah
- JHU ICMIC Program, Division of Cancer Imaging Research, Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Flonne Wildes
- JHU ICMIC Program, Division of Cancer Imaging Research, Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Samata Kakkad
- JHU ICMIC Program, Division of Cancer Imaging Research, Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Dmitri Artemov
- JHU ICMIC Program, Division of Cancer Imaging Research, Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Zaver M Bhujwalla
- JHU ICMIC Program, Division of Cancer Imaging Research, Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
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Winnard PT, Bharti SK, Penet MF, Marik R, Mironchik Y, Wildes F, Maitra A, Bhujwalla ZM. Detection of Pancreatic Cancer-Induced Cachexia Using a Fluorescent Myoblast Reporter System and Analysis of Metabolite Abundance. Cancer Res 2015; 76:1441-50. [PMID: 26719527 DOI: 10.1158/0008-5472.can-15-1740] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 12/21/2015] [Indexed: 01/06/2023]
Abstract
The dire effects of cancer-induced cachexia undermine treatment and contribute to decreased survival rates. Therapeutic options for this syndrome are limited, and therefore efforts to identify signs of precachexia in cancer patients are necessary for early intervention. The applications of molecular and functional imaging that would enable a whole-body "holistic" approach to this problem may lead to new insights and advances for diagnosis and treatment of this syndrome. Here we have developed a myoblast optical reporter system with the purpose of identifying early cachectic events. We generated a myoblast cell line expressing a dual tdTomato:GFP construct that was grafted onto the muscle of mice-bearing human pancreatic cancer xenografts to provide noninvasive live imaging of events associated with cancer-induced cachexia (i.e., weight loss). Real-time optical imaging detected a strong tdTomato fluorescent signal from skeletal muscle grafts in mice with weight losses of only 1.2% to 2.7% and tumor burdens of only approximately 79 to 170 mm(3). Weight loss in cachectic animals was also associated with a depletion of lipid, cholesterol, valine, and alanine levels, which may provide informative biomarkers of cachexia. Taken together, our findings demonstrate the utility of a reporter system that is capable of tracking tumor-induced weight loss, an early marker of cachexia. Future studies incorporating resected tissue from human pancreatic ductal adenocarcinoma into a reporter-carrying mouse may be able to provide a risk assessment of cachexia, with possible implications for therapeutic development.
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Affiliation(s)
- Paul T Winnard
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Santosh K Bharti
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Marie-France Penet
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland. Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Radharani Marik
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Yelena Mironchik
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Flonne Wildes
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Anirban Maitra
- Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland. The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Zaver M Bhujwalla
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland. Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
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Krishnamachary B, Stassinopoulos I, Kakkad SM, Penet MF, Jacob D, Wildes F, Mironchik Y, Pathak A, Solaiyappan M, Bhujwalla ZM. Abstract 4021: Cyclooxygenase-2 downregulation reduces activated fibroblasts and modifies the extracellular matrix in MDA-MB-231 breast cancer xenograft. Cancer Res 2015. [DOI: 10.1158/1538-7445.am2015-4021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
COX-2 is an important mediator of inflammation that significantly influences tumor angiogenesis, invasion and metastasis. Here, we have investigated the role of COX-2 in modifying the number of activated cancer associated fibroblasts (CAFs) and in altering the extracellular matrix (ECM) in a breast cancer model.
To investigate the role of COX-2 in modulating the ECM, we used an MDA-MB-231 cell clone (Clone 13) expressing a short hairpin RNA (shRNA) to downregulate COX-2 [1]. Clone 13 cells were characterized for significantly lower basal and TPA-induced COX-2 and PGE2 expression compared to parental MDA-MB-231 cells using ELISA (PGE2), western blot (COX-2 protein) and q-RT-PCR (COX-2 mRNA). Tumors were derived from parental (n = 5) and Clone 13 (n = 6) MDA-MB-231 cells following inoculation in the mammary fat pad in SCID mice. Tumors were excised at ∼ 500 mm3 and immunohistochemically stained to quantify vessel density (CD31) and activated CAFs (α-smooth muscle actin (SMA)) in 5 μm thick formalin fixed sections. Stained sections were digitally scanned and positive staining quantified using manufacturer supplied software (Aperio Technologies, CA).
Clone 13 tumors showed delayed tumor growth compared to parental MDA-MB-231 tumors. We have previously observed that collagen 1 (Col1) fiber density and fiber volume were significantly lower in COX-2 reduced Clone 13 tumors compared to parental tumors [2]. While cancer cells shape Col1 fiber patterns through the secretion of various enzymes, Col1 fiber is laid down by activated CAFs within or around the tumor. Quantification of activated CAFs by immunohistochemistry for α-SMA in the tumors, and immunoblotting for α-SMA of crude protein extracted from the tumors, revealed significantly fewer CAFs and significantly reduced levels of α-SMA protein in Clone 13 tumors compared to parental MDA-MB-231 tumors. We previously observed a significant decrease in permeability as well as reduced influx and efflux of macromolecular transport in Clone 13 tumors compared to parental tumors, but no difference in vascular volume [2]. Immunohistochemistry for CD31 staining of endothelial cells did not detect a significant difference in CD31 density between Clone 13 and parental tumors further confirming our previous observations about vascular volume. These data reveal the multi-faceted effects of COX-2 in modifying the structure and function of the ECM, and identify the ability to attract and activate fibroblasts as one mechanism by which COX-2 modifies the ECM.
Acknowledgements: We thank Mr. Gary Cromwell for technical assistance. This work was supported by NIH R01CA82337 and P50 CA103175.
References: [1] Stasinopoulos, I., et al., Mol Cancer Res, 2007; [2], Stasinopoulos, I., et al., AACR, 2013 Chicago.
Citation Format: Balaji Krishnamachary, Ioannis Stassinopoulos, Samata M. Kakkad, Marie-France Penet, Desmond Jacob, Flonne Wildes, Yelena Mironchik, Arvind Pathak, Meiyappan Solaiyappan, Zaver M. Bhujwalla. Cyclooxygenase-2 downregulation reduces activated fibroblasts and modifies the extracellular matrix in MDA-MB-231 breast cancer xenograft. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4021. doi:10.1158/1538-7445.AM2015-4021
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Winnard PT, Penet MF, Mironchik Y, Wildes F, Maitra A, Bhujwalla ZM. Abstract 5110: Initial characterization of an optical reporter myoblast cell line for non-invasive imaging in a cancer cachexia model in mice. Cancer Res 2015. [DOI: 10.1158/1538-7445.am2015-5110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Cancer associated cachexia affects a majority of patients during cancer progression, compromising therapeutic interventions and contributing to decreased survival rates. Identifying factors involved in the onset of cachexia will provide a better understanding of early treatment strategies. To this end, we developed a mouse model system that allows for real time longitudinal monitoring of cancer induced wasting and has the potential of identifying early cachectic events. Several attributes of our system are new. 1) The construction of a dual optical reporter vector with green fluorescence protein (GFP) expression constitutively driven from an EF1α promoter and red fluorescence protein (tdTomato) expression driven by an engineered skeletal muscle specific inducible promoter. The latter is a synthetic sequence of a triple-tandem repeat of the glucocorticoid-FOXO1 response element region from the proximal promoter of the human MuRF1 gene. 2) Generation of a rat L6 myoblast optical reporter cell line (To3B cells) with stable integration of the dual reporter vector construct, which provides living reporter grafts within mouse muscle. 3) A human pancreatic cancer cell line (Pa04C) that as an orthotopic or subcutaneous xenograft causes weight loss in male SCID mice. In preliminary studies, we tested several human pancreatic cancer cell lines as orthotopic xenografts in male SCID mice. We found that red fluorescence signals were reproducibly detected in live mice only from To3B grafts in mice undergoing weight loss, while graft size and viability were readily monitored by imaging GFP fluorescence in all animals. In addition, mice bearing Pa04C tumors lost the most weight while mice bearing Panc1 tumors gained weight. Therefore, Pa04C and Panc1 cells were used for subcutaneous xenografts in male SCID mice and weight loss was followed with optical monitoring of To3B grafts. Importantly, in weight losing mice, we found that red fluorescence could be detected and quantified at a nascent stage of the syndrome; e.g., unambiguous red fluorescent signals were quantified at weight losses of only 1.2 to 2.7% at very low tumor burdens of only ∼0.079 to ∼0.170 cm3. Red fluorescence remained very low to undetectable in mice that gained weight. Tumor sizes were comparable between groups, which was an indication that factors independent of tumor growth were involved in switching on red fluorescence. Ex vivo fluorescence microscopy confirmed a robust presence of red fluorescence only in To3B grafts in skeletal muscle from Pa04C tumor bearing mice. The evidence from this initial development of a unique optical reporter myoblast cell line indicates the potential to detect the onset of cancer cachexia. These studies set the ground work for future research aimed at identifying initiating systemic as well as local molecular events in the muscle of cachectic mice.
Supported by NIH P50CA103175
Citation Format: Paul T. Winnard, Marie-France Penet, Yelena Mironchik, Flonne Wildes, Anirban Maitra, Zaver M. Bhujwalla. Initial characterization of an optical reporter myoblast cell line for non-invasive imaging in a cancer cachexia model in mice. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5110. doi:10.1158/1538-7445.AM2015-5110
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Affiliation(s)
| | | | | | - Flonne Wildes
- 1Johns Hopkins University Medical School, Baltimore, MD
| | - Anirban Maitra
- 2University of Texas MD Anderson Cancer Center, Houston, TX
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Bharti SK, Krishnamachary B, Zhu W, Wildes F, Mironchik Y, Kakkad SM, Artemov D, Bhujwalla ZM. Abstract 1490: Matrigel rescues breast cancer cells from the growth inhibitory effects of HIF-1α and HIF-2α silencing. Cancer Res 2015. [DOI: 10.1158/1538-7445.am2015-1490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Tumor microenvironments are frequently hypoxic and result in the stabilization of hypoxia inducible factors (HIF-1/2) that transcriptionally activate genes involved in invasion, metastasis, metabolism and angiogenesis [1]. The role of hypoxia and the contribution of HIF in the angiogenic switch leading to tumor progression and resistance to treatment are well documented. This angiogenic response to HIF activity is largely mediated through activation of vascular endothelial growth factor (VEGF). Noninvasive characterization of the loss of both isoform of HIFs (HIF-1α & HIF-2α) on tumor vascularization is relatively unexplored. Here we investigated the effect of HIF silencing on tumor growth in the presence or absence of Matrigel that resembles the complex extracellular matrix (ECM) found in most tumors and determined its effect on tumor vasculature using noninvasive MRI.
MDA-MB-231 human breast cancer cells expressing shRNA against both HIF-1α and HIF-2α (231-DK) were established as previously described [2]. In vivo studies were performed using MDA-MB-231 breast cancer cells expressing an empty vector control (231-EV) and 231-DK cells implanted in the mammary fat pad of female SCID mice. Tumor growth curves were obtained from cells inoculated either in 0.05 ml of Hanks balanced salt solution (HBSS) or together with Matrigel solution (8.8 mg/ml). All MRI studies were performed on a 9.4T Bruker Biospec horizontal bore scanner. 3D maps of vascular volume (V/V) and permeability (VP) were obtained using a rapid gradient-echo sequence and albumin-GdDTPA (0.5 g/kg) as the contrast agent (CA). A proton density (PD) image was acquired prior to CA injection, using a 3D gradient echo sequence, with TE/TR = 1.5/10 ms and 3° flip angle and analysis of the images were performed as previously described [3].
Exposure to hypoxia showed no increase in HIF-1 or 2α protein expression in 231-DK compared to 231-EV cells. A significant growth advantage of the 231-DK cells in vivo was observed when inoculated in the presence of Matrigel compared to 231-DK in HBSS. Growth advantage of tumors in the presence of Matrigel was less dramatic for 231-EV cells. When inoculated with Matrigel, 3D reconstructed maps of 231-DK tumors showed significantly increased VP compared to 231-EV tumors with no difference in the VV. Increased vascular permeability in tumors derived from 231-DK cells compared to tumors derived from 231-EV cells can be attributed to VEGF in the Matrigel that is known to exhibit paracrine effects. These data suggest that ECM components may modulate molecular targeting and highlight the importance of the tumor microenvironment in modifying HIF silencing effects. Work is under way to analyze the effects on the metastatic burden in these systems.
References: 1. Semenza, Trends in Mol. Med, 2002; 2. Krishnamachary et al., PLoS One, 2012; 3. Zhu et al., Magn Reson Mater Physics, 2014.
Supported by NIH R01CA136576 and P50 CA103175.
Citation Format: Santosh K. Bharti, Balaji Krishnamachary, Wenlian Zhu, Flonne Wildes, Yelena Mironchik, Samata M. Kakkad, Dmitri Artemov, Zaver M. Bhujwalla. Matrigel rescues breast cancer cells from the growth inhibitory effects of HIF-1α and HIF-2α silencing. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1490. doi:10.1158/1538-7445.AM2015-1490
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Affiliation(s)
- Santosh K. Bharti
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Balaji Krishnamachary
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Wenlian Zhu
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Flonne Wildes
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Yelena Mironchik
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Samata M. Kakkad
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Dmitri Artemov
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Zaver M. Bhujwalla
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
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Korangath P, Teo WW, Sadik H, Han L, Mori N, Huijts CM, Wildes F, Bharti S, Zhang Z, Santa-Maria CA, Tsai H, Dang CV, Stearns V, Bhujwalla ZM, Sukumar S. Targeting Glutamine Metabolism in Breast Cancer with Aminooxyacetate. Clin Cancer Res 2015; 21:3263-73. [PMID: 25813021 DOI: 10.1158/1078-0432.ccr-14-1200] [Citation(s) in RCA: 110] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Accepted: 03/12/2015] [Indexed: 11/16/2022]
Abstract
PURPOSE Glutamine addiction in c-MYC-overexpressing breast cancer is targeted by the aminotransferase inhibitor, aminooxyacetate (AOA). However, the mechanism of ensuing cell death remains unresolved. EXPERIMENTAL DESIGN A correlation between glutamine dependence for growth and c-MYC expression was studied in breast cancer cell lines. The cytotoxic effects of AOA, its correlation with high c-MYC expression, and effects on enzymes in the glutaminolytic pathway were investigated. AOA-induced cell death was assessed by measuring changes in metabolite levels by magnetic resonance spectroscopy (MRS), the effects of amino acid depletion on nucleotide synthesis by cell-cycle and bromodeoxyuridine (BrdUrd) uptake analysis, and activation of the endoplasmic reticulum (ER) stress-mediated pathway. Antitumor effects of AOA with or without common chemotherapies were determined in breast cancer xenografts in immunodeficient mice and in a transgenic MMTV-rTtA-TetO-myc mouse mammary tumor model. RESULTS We established a direct correlation between c-MYC overexpression, suppression of glutaminolysis, and AOA sensitivity in most breast cancer cells. MRS, cell-cycle analysis, and BrdUrd uptake measurements indicated depletion of aspartic acid and alanine leading to cell-cycle arrest at S-phase by AOA. Activation of components of the ER stress-mediated pathway, initiated through GRP78, led to apoptotic cell death. AOA inhibited growth of SUM159, SUM149, and MCF-7 xenografts and c-myc-overexpressing transgenic mouse mammary tumors. In MDA-MB-231, AOA was effective only in combination with chemotherapy. CONCLUSIONS AOA mediates its cytotoxic effects largely through the stress response pathway. The preclinical data of AOA's effectiveness provide a strong rationale for further clinical development, particularly for c-MYC-overexpressing breast cancers.
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Affiliation(s)
- Preethi Korangath
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Wei Wen Teo
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Helen Sadik
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Liangfeng Han
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Noriko Mori
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Charlotte M Huijts
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Flonne Wildes
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Santosh Bharti
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Zhe Zhang
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Cesar A Santa-Maria
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Hualing Tsai
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Chi V Dang
- Department of Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania
| | - Vered Stearns
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Zaver M Bhujwalla
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Saraswati Sukumar
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
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Krishnamachary B, Bharti SK, Penet MF, Kakkad SM, Wildes F, Zoltani K, Mironchik Y, Bhujwalla ZM. Abstract 509: Hypoxia and HIF silencing mediated dysregulation of total choline, CD44 expression, and metastatic burden in MDA-MB-231 human breast cancers. Cancer Res 2014. [DOI: 10.1158/1538-7445.am2014-509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Hypoxic tumors frequently exhibit an aggressive phenotype due to dysregulated gene expression and metabolic changes. Hypoxia results in the stabilization of hypoxia inducible factors (HIF-1/2) that transcriptionally activate genes involved in invasion, metastasis, metabolism, and in the adaptation of cancer cells to their microenvironment. In breast cancer, stem-like breast cancer cells that survive, repopulate and metastasize to distant locations, have elevated expression of CD44. In a previous study, we observed elevated expression of CD44 in hypoxic tumor regions, and identified HIF-1α as a regulator of CD44 expression in breast cancer cells under hypoxic conditions [1]. Hypoxia has also been implicated in increasing the activity of choline kinase (Chk)-alpha, the enzyme responsible for elevated phosphocholine (PC) and total choline (tCho) consistently observed in cancers [2]. In previous studies, lentiviral transduction of MDA-MB-231 breast cancer cells (231 cells) with shRNA against Chk-alpha and the in vivo delivery of the Chk-shRNA virus into tumor bearing mice resulted in decreased CD44 message and expression together with effective silencing of Chk message and expression [3]. Here, using non-invasive proton magnetic resonance spectroscopic imaging (1H MRSI), we have established the importance of HIF in reducing total choline and metastatic tumor burden, and have identified a role for CD44 in establishing lung metastasis. HIF silencing in MDA-MB-231 cells significantly delayed tumor growth in mice. Both, the in vitro 1H and 31P MR spectra and in vivo 1H MRS images of tumors derived from engineered cells showed decreased tCho levels and distribution. This decrease of tCho was statistically significant in tumors derived from double silenced cells. Western blot analysis of tumors detected a decrease in Chk expression in double silenced (HIF-1 and 2) tumors. Silencing HIF-1α, -2α or both resulted in a significant reduction of metastatic lung burden in mice. Additionally, HIF-2α silencing was more effective at reducing lung colonization than HIF-1α, while silencing both was the most effective. Although metastatic burden decreased in HIF-1α silenced cells, the percentage of cells with high CD44 expression in the metastatic foci was comparable to that in the wild type or empty vector foci. These data identify the importance of targeting HIF and CD44 to prevent lung colonization and disrupt the metastatic cascade.
This work was supported by NIH R01CA136576 and P50 CA103175. We thank Mr. Gary Cromwell for valuable technical assistance.
References: 1. Krishnamachary B. et al., PLoS One, 2012; 2. Glunde, K., et al., Cancer Res, 2008; 3. Ackerstaff E. et al., Neoplasia. 2007.
Citation Format: Balaji Krishnamachary, Santosh Kumar Bharti, Marie-France Penet, Samata M. Kakkad, Flonne Wildes, Keve Zoltani, Yelena Mironchik, Zaver M. Bhujwalla. Hypoxia and HIF silencing mediated dysregulation of total choline, CD44 expression, and metastatic burden in MDA-MB-231 human breast cancers. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 509. doi:10.1158/1538-7445.AM2014-509
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Jacob D, Kakkad SM, Krishnamachary B, Stasinopoulos I, Solaiyappan M, Wildes F, Glunde K, Bhujwalla ZM. Abstract 4890: Collagen 1 fibers are a key component in the establishment of distant pulmonary metastasis by breast cancer cells. Cancer Res 2014. [DOI: 10.1158/1538-7445.am2014-4890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
We previously observed that silencing COX-2 significantly reduced the expression of degradative enzymes such as matrix metalloproteinase 1 (MMP1), and altered the expression of ECM components such as hyaluronan and lumican that play a role in intra-fibrillar collagen spacing [1]. We have also observed that primary human breast cancers that have metastasized have higher collagen 1 (Col1) fiber density and volume [2]. Here, for the first time, we have investigated Col1 fiber patterns in metastatic lung nodules established by metastatic MDA-MB-231 breast cancer cells and their subclone Clone 13 cells that express shRNA to significantly reduce, but not silence, COX-2 expression.
Second harmonic generation (SHG) microscopy studies were performed on H&E stained lung sections obtained from SCID mice five weeks post intravenous injection of MDA-MB-231 (five mice) and Clone 13 (three mice) human breast cancer cells. SHG images of 5-7 fields of view per mouse were acquired from the lung sections on an Olympus FV1000MPE multiphoton microscope, and analyzed for inter-fiber distance and percentage of fiber per metastatic area using in-house software [2]. Reducing COX-2 expression resulted in a significant reduction of metastatic lung burden in mice. Analysis of the Col1 fiber structures of similar sized metastatic nodules revealed significantly fewer fibers and larger inter fiber distance in lung nodules of mice injected with Clone 13 cells compared to parental MDA-MB-231 cells.
Reducing COX-2 resulted in the establishment of significantly fewer metastatic lung nodules with significantly sparser Col1 fibers. These data suggest that the ability to lay down Col1 fibers is a key requirement for the successful establishment of metastatic lesions. Reducing COX-2 expression in MDA-MB-231 breast cancer cells affects the ability of these cancer cells to lay down a Col1 fiber scaffold suitable for cancer cell growth in the lungs. These data identify new aspects of the role of Col1 fibers and COX-2 in the establishment of metastatic lesions.
References: [1] I. Stasinopoulos et al., Neoplasia (2008); [2] S. Kakkad et al., J Biomed Opt (2012).
This work was supported by NIH R01CA82337 and P50CA103175.
Citation Format: Desmond Jacob, Samata M. Kakkad, Balaji Krishnamachary, Ioannis Stasinopoulos, Meiyappan Solaiyappan, Flonne Wildes, Kristine Glunde, Zaver M. Bhujwalla. Collagen 1 fibers are a key component in the establishment of distant pulmonary metastasis by breast cancer cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4890. doi:10.1158/1538-7445.AM2014-4890
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Korangath P, Sadik H, Mori N, Wildes F, Zhang Z, Bhujwalla Z, Sukumar S. Abstract P3-01-01: Targeting glutamine metabolism in breast cancer for therapy. Cancer Res 2013. [DOI: 10.1158/0008-5472.sabcs13-p3-01-01] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Metabolic reprogramming of cancer cells is observed in different types of tumors including breast. Oncogenic signals aid changes in metabolism that provide selective advantage to the cancer cells to meet their energy requirements to accomplish rapid proliferation. The increased dependence on the glycolytic pathway for energy called the “Warburg effect” was reported by Otto Warburg several decades ago. Our recent understanding of cancer metabolism has thrown light on alternative energy sources, especially glutamine and other branched chain amino acids. The role of glutamine in breast cancer cell growth has not yet been studied extensively.
In this study we found that a number of breast cancer cell lines, especially those negative for ER, PR, HER2, display a high dependence on glutamine for their survival and growth. Interestingly, most of these glutamine-dependent cell lines express high levels of c-myc protein. Consistent with their growth dependency on glutamine, transaminases responsible for entry of glutamine into the tricarboxylic acid cycle are transcriptionally up regulated under low glutamine conditions. Consequently, growth of these cancer cell lines was found to be specifically inhibited by the transaminase inhibitor, amino oxyacetate (AOA). Moreover, the AOA mediated cytotoxic effect was partially c-myc dependent. Through 1H-NMR studies of AOA-treated cells we show that in addition to glutamine, AOA treatment decreases the aspartate and alanine content in the cells. In line with these findings, exogenous supplementation with aspartate partially rescued the cells from the growth inhibitory effects of AOA. Flow cytometry analysis showed that AOA causes cell cycle arrest in the S phase. AOA also had significant inhibitory effect on in vivo growth of rapidly growing SUM 149 and SUM159 xenografts in immunodeficient mice. When combined with chemotherapeutic agents, doxorubicin and carboplatin, AOA inhibited growth of MDA-MB-231 xenograft tumors more effectively than AOA alone. Lastly we present evidence that the cytotoxic effect of AOA is mediated through activation of the ER stress pathway, combined with depletion of key amino acids and likely, a reduction in the nucleoside pool in the cells. Our preclinical studies, both in vitro and in vivo, combined with development of intermediate markers of response, provide a strong rationale for testing AOA for therapy in Phase 0 clinical trials.
Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-01-01.
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Affiliation(s)
| | - H Sadik
- Johns Hopkins University, Baltimore, MD
| | - N Mori
- Johns Hopkins University, Baltimore, MD
| | - F Wildes
- Johns Hopkins University, Baltimore, MD
| | - Z Zhang
- Johns Hopkins University, Baltimore, MD
| | | | - S Sukumar
- Johns Hopkins University, Baltimore, MD
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Mori N, Gadiya M, Wildes F, Krishnamachary B, Glunde K, Bhujwalla ZM. Characterization of choline kinase in human endothelial cells. NMR Biomed 2013; 26:1501-1507. [PMID: 23775813 PMCID: PMC3800480 DOI: 10.1002/nbm.2983] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Revised: 05/08/2013] [Accepted: 05/10/2013] [Indexed: 06/02/2023]
Abstract
High choline kinase-α (Chk-α) expression is frequently observed in cancer cells, making it a novel target for pharmacological and molecular inhibition. As inhibiting agents are delivered systemically, it is important to determine Chk-α expression levels in endothelial cells that line both normal and tumor vasculature, and the effect of Chk-α downregulation on these cells. Here, we characterized Chk-α expression and the effect of its downregulation in human umbilical vein endothelial cells (HUVECs) relative to MDA-MB-231 human breast cancer cells. We used small interfering RNA (siRNA) to downregulate Chk-α expression. Basal mRNA levels of Chk-α were approximately three-fold lower in HUVECs relative to MDA-MB-231 breast cancer cells. Consistent with the differences in Chk-α protein levels, phosphocholine levels were approximately 10-fold lower in HUVECs relative to MDA-MB-231 cells. Transient transfection with siRNA-Chk resulted in comparable levels of mRNA and protein in MDA-MB-231 breast cancer cells and HUVECs. However, there was a significant reduction in proliferation in MDA-MB-231 cells, but not in HUVECs. No significant difference in CD31 immunostaining was observed in tumor sections obtained from mice injected with control luciferase-short hairpin (sh)RNA or Chk-shRNA lentivirus. These data suggest that systemically delivered agents that downregulate Chk-α in tumors will not affect endothelial cell proliferation during delivery, and further support the development of Chk-α downregulation as a cancer-specific treatment.
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Affiliation(s)
- Noriko Mori
- JHU ICMIC Program, Division of Cancer Imaging Research, The
Russell H. Morgan Department of Radiology and Radiological Science
| | - Mayur Gadiya
- JHU ICMIC Program, Division of Cancer Imaging Research, The
Russell H. Morgan Department of Radiology and Radiological Science
| | - Flonne Wildes
- JHU ICMIC Program, Division of Cancer Imaging Research, The
Russell H. Morgan Department of Radiology and Radiological Science
| | - Balaji Krishnamachary
- JHU ICMIC Program, Division of Cancer Imaging Research, The
Russell H. Morgan Department of Radiology and Radiological Science
| | - Kristine Glunde
- JHU ICMIC Program, Division of Cancer Imaging Research, The
Russell H. Morgan Department of Radiology and Radiological Science
| | - Zaver M. Bhujwalla
- JHU ICMIC Program, Division of Cancer Imaging Research, The
Russell H. Morgan Department of Radiology and Radiological Science
- Sidney Kimmel Comprehensive Cancer Center, The Johns
Hopkins University, School of Medicine, Baltimore, Maryland 21205
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Mori N, Wildes F, Glunde K, Bhujwalla ZM. Abstract 1707: Understanding the role of choline kinase in breast cancer. Cancer Res 2013. [DOI: 10.1158/1538-7445.am2013-1707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Choline kinase (Chk), the enzyme that converts choline to phosphocholine (PC) in the choline phospholipid metabolism pathway has been evaluated as a novel target since increased levels of Chk-α and PC are consistently observed in aggressive cancers including breast cancer. We previously showed that the Chk inhibitor, V-11-0711 (Vertex Pharmaceuticals (Europe) Ltd), which reduces the function of Chk-α by binding to the active site and inhibiting the catalytic activity but not affecting Chk-α protein levels, had no effect on MDA-MB-231 cell proliferation, although downregulation of Chk with siRNA (siRNA-chk) reduced proliferation. Here we have confirmed and expanded these observations in the SUM149 triple negative inflammatory breast cancer cell line. These data confirm the aberrant expression of this enzyme and provide new insights into its role in breast cancer.
The cell proliferation assay (cell counting kit-8, Dojindo) detected no significant reduction of viability in SUM149 cells treated with up to 5μM V-11-0711 for 48 h. After 48 h treatment with 0.1μM and 1μM V-11-0711, Chk-α protein levels in SUM149 cells were stable. Fully relaxed 1H NMR spectroscopy of water-soluble phase of cell extracts performed on a Bruker Avance 500 spectrometer showed that levels of PC and total choline (PC + glycerophosphocholine (GPC) + free choline) decreased significantly and dose dependently after treatment with 0.1μM and 1μM V-11-0711. GPC levels decreased significantly only following treatment with 1μM V-11-0711. Treatment with 1μM V-11-0711 reduced PC to almost non-detectable level. We have previously shown that the downregulation of Chk expression significantly reduced the proliferation in breast cancer cells and tumors [1-3]. Our results here indicate that reduction of PC under these conditions does not markedly affect the proliferation of breast cancer cells if Chk-α protein levels are not reduced. To further investigate if reduced protein levels of Chk-α affect proliferation in SUM149 cells, we transfected cells with siRNA-chk. siRNA-chk reduced Chk-α protein to undetectable levels and proliferation was significantly reduced whether 0.1μM V-11-0711 was present or not. Our results demonstrate that, similar to MDA-MB-231 cells, reduction of PC has little affect on breast cancer cell proliferation as long as Chk-α protein levels are not reduced. These data are consistent with results obtained by Miyake et al., [4] on the potential role of Chk-α as a chaperone protein, and suggest that the Chk-α protein may be essential in cancer cell proliferation. The data support the development of strategies that destabilize or downregulate Chk-α protein.
[1] Glunde K et al, Cancer Res, 65, (2005); [2] Mori N et al, Cancer Res, 67, (2007); [3] Krishnamachary B et al, Cancer Res, 69, (2009); [4] Miyake T et al., Oncogene (2011). This work was supported by NIH R01 CA73850 and P50 CA103175.
Citation Format: Noriko Mori, Flonne Wildes, Kristine Glunde, Zaver M. Bhujwalla. Understanding the role of choline kinase in breast cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1707. doi:10.1158/1538-7445.AM2013-1707
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Affiliation(s)
- Noriko Mori
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Flonne Wildes
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Kristine Glunde
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Zaver M. Bhujwalla
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
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Krishnamachary B, Kakkad S, Penet MF, Zoltani K, Raman V, Gadiya M, Mironchik Y, Wildes F, Bhujwalla ZM. Abstract 3745: Validation of the co-expression of breast cancer stem cell markers with HIF-1α in tumors. Cancer Res 2013. [DOI: 10.1158/1538-7445.am2013-3745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Stem-like breast cancer cells (SBCCs) are drug resistant, invasive, and likely to lead to tumor recurrence and repopulation. High expression of the adhesion molecule CD44, the drug transporter ABCG2, and of the enzyme ALDH1A1 are well-established markers associated with SBCC-enriched tumor populations [1]. Hypoxic tumor microenvironments are frequently associated with increased aggressiveness and resistance to chemo and radiation therapy. Hypoxia results in the stabilization of the hypoxia inducible factor -1 (HIF-1), a transcription factor that activates a battery of genes, including those associated with SBCCs, that help cancer cells to survive, repopulate and finally metastasize to distant location. Recently, we reported the role of hypoxia and HIF-1α in regulating the expression of CD44 and its variant isoforms in triple negative breast cancer [2]. Here we have validated the association between hypoxia and CD44 expression in these tumors. We used tumors derived from MDA-MB-231 cells genetically engineered to express red fluorescent protein (tdtomato) under the control of hypoxia response element (231-HRE-RFP). Optical imaging (Nikon fluorescence microscope) was performed to detect hypoxia in fresh tissue slices, followed by immunohistochemistry (IHC) staining for HIF-1α, CD44 and ABCG2 expression in 5μm thickness adjacent sections from paraffin embedded 231-HRE-RFP tumors. Slides were scanned on an Image Scope digital scanner. Analysis for HIF-1 α nuclear staining was performed by drawing regions of interest (ROI) on scanned images using manufacturer supplied macro (Aperio Technologies Inc. CA, USA). For co-registration and quantification studies, ROI drawn images of HIF-1α and CD44 were co-registered to the bright field and fluorescent optical images using an in-house program developed in MATLAB (Mathworks Inc.). Statistical analysis (t-test) was performed using Microsoft Excel 2010 (Microsoft Inc. Seattle, USA). Following co-registration, intensely fluorescing regions of 231-HRE-RFP tumors were found to be associated with elevated nuclear HIF-1α expression and higher CD44 membrane expression. A trend of increased optical intensity (p≤0.09) and significantly increased CD44 pixel intensity (p≤0.05) was observed in the high HIF-1α ROI compared to the low HIF-1α ROI. Work is under way to co-register other breast cancer stem cell markers such as ABCG2 and ALDH1A1 in these tumors. These data further highlight the role of hypoxia in engendering a stem-like phenotype, and the potential importance of targeting hypoxia to minimize the burden of cells with stem-like characteristics in tumors. All animal protocols were approved by the JHU animal care and use committee.
This work was supported by NIH R01CA136576 and P50 CA103175.
1. Al-Hajj, M et al., Proc Natl Acad Sci U S A, 2003.
2. Krishnamachary.B. et al., PLoS One 2012;7(8)e44078-
Citation Format: Balaji Krishnamachary, Samata Kakkad, Marie-France Penet, Keve Zoltani, Venu Raman, Mayur Gadiya, Yelena Mironchik, Flonne Wildes, Zaver M. Bhujwalla. Validation of the co-expression of breast cancer stem cell markers with HIF-1α in tumors. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3745. doi:10.1158/1538-7445.AM2013-3745
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Shah T, Stasinopoulos I, Wildes F, Kakkad S, Artemov D, Bhujwalla ZM. Noninvasive imaging identifies new roles for cyclooxygenase-2 in choline and lipid metabolism of human breast cancer cells. NMR Biomed 2012; 25:746-54. [PMID: 21953546 PMCID: PMC4337877 DOI: 10.1002/nbm.1789] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2011] [Revised: 07/27/2011] [Accepted: 08/12/2011] [Indexed: 05/19/2023]
Abstract
The expression of cyclooxygenase-2 (COX-2) is observed in approximately 40% of breast cancers. A major product of the COX-2-catalyzed reaction, prostaglandin E(2), is an inflammatory mediator that participates in several biological processes, and influences invasion, vascularization and metastasis. Using noninvasive MRI and MRS, we determined the effect of COX-2 downregulation on the metabolism and invasion of intact poorly differentiated MDA-MB-231 human breast cancer cells stably expressing COX-2 short hairpin RNA. Dynamic tracking of invasion, extracellular matrix degradation and metabolism was performed with an MRI- and MRS-compatible cell perfusion assay under controlled conditions of pH, temperature and oxygenation over the course of 48 h. COX-2-silenced cells exhibited a significant decrease in invasion relative to parental cells that was consistent with the reduced expression of invasion-associated matrix metalloproteinase genes and an increased level of the tissue inhibitor of metalloproteinase-1. We identified, for the first time, a role for COX-2 in mediating changes in choline phospholipid metabolism, and established that choline kinase expression is partly dependent on COX-2 function. COX-2 silencing resulted in a significant decrease in phosphocholine and total choline that was detected by MRS. In addition, a significant increase in lipids, as well as lipid droplet formation, was observed. COX-2 silencing transformed parental cell metabolite patterns to those characteristic of less aggressive cancer cells. These new functional roles of COX-2 may identify new biomarkers and new targets for use in combination with COX-2 targeting to prevent invasion and metastasis.
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Affiliation(s)
| | | | | | | | | | - Zaver M. Bhujwalla
- Correspondence to: Z. M. Bhujwalla, Department of Radiology, Johns Hopkins University School of Medicine, 208C Traylor Bldg., 720 Rutland Ave., Baltimore, MD 21205, USA.
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Mori N, Stasinopoulos I, Wildes F, Bhujwalla ZM. Abstract 5162: COX-2 downregulation protects SUM-149 cells following targeting of choline phospholipid metabolism. Cancer Res 2012. [DOI: 10.1158/1538-7445.am2012-5162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Enzymes in the choline phospholipid metabolism pathway such as choline kinase (Chk) and phopholipase D1 (PLD1) are being evaluated as novel targets in cancer therapy since these enzymes are overexpressed in aggressive cancers including breast cancer. We have previously shown that single and double downregulation of Chk and PLD1 significantly reduced cell proliferation in breast cancer cells. We also observed a close association between Chk and cyclooxygenase 2 (COX-2), an inducible enzyme that mediates the inflammatory response and plays a role in cancer invasion, angiogenesis and metastasis. COX-2 inhibition is also being considered as a strategy for cancer prevention or treatment. Here we investigated the effect of the COX-2 downregulation combined with PLD1 and Chk downregulation using siRNA, on cell proliferation to achieve improved control and minimize compensatory responses that allow the cell to survive or adapt. The triple negative inflammatory breast cancer cell line, SUM149, was used in this study. Cells were transfected with 25 nM siRNA against COX-2 (siRNA-cox2), PLD1 (siRNA-pld1) or Chk (siRNA-chk) either singly or combined for 48 h. Untreated cells and the transfection reagent (DharmaFECT) treatment were used as negative controls. Immunoblot analysis was done after 48 h transfection using antibodies specific to COX-2, PLD1, Chk-α, and GAPDH (as a loading control). Proliferation/viability of cells was determined using the CCK-8 assay (cell counting kit-8, Dojindo) at day 2 and day 5 after transfection. After 48 h transfection with siRNA-pld1 or siRNA-chk, PLD1 or Chk-α protein were downregulated significantly and COX-2 protein was upregulated. When we combined downregulation of Chk or PLD1 with COX-2 dowregulation, we established significantly lower COX-2 protein levels compared to single knockdown of Chk and PLD1. COX-2 downregulation alone did not significantly reduce proliferation. Downregulation of PLD1 or Chk, however, significantly reduced proliferation compared to untreated cells (PLD1: –75%, Chk: –68%). When we combined COX-2 downregulation with PLD1 or Chk downregulation, cell survival was significantly higher than with just PLD1 or Chk alone (PLD1: –46%. Chk: –28%). These results suggest that COX-2 downregulation rescues cells following downregulation of PLD1 or Chk in SUM149 cells, identifying a different facet of COX-2 in the choline phospholipid pathway. This work supported by R01 CA82337
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5162. doi:1538-7445.AM2012-5162
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Affiliation(s)
- Noriko Mori
- 1JHU ICMIC Program, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Ioannis Stasinopoulos
- 1JHU ICMIC Program, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Flonne Wildes
- 1JHU ICMIC Program, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Zaver M. Bhujwalla
- 1JHU ICMIC Program, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
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Mori N, Gadiya M, Wildes F, Krishnamachary B, Bhujwalla ZM. Abstract 980: Downregulation of choline kinase does not affect endothelial cell proliferation. Cancer Res 2011. [DOI: 10.1158/1538-7445.am2011-980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Elevated phosphocholine (PC) and high choline kinase (Chk) expression are typically observed in cancer. Chk, the enzyme that converts choline (Cho) to PC, is being evaluated as a novel target in cancer treatment using pharmacological and molecular inhibition. We have previously shown that both transient transfection and stable expression of siRNA (siRNA-chk) and shRNA against choline kinase-α (Chk) significantly reduced proliferation in breast cancer cells [1] and tumors [2]. The downregulation of Chk in nonmalignant MCF-12A cells resulted in an almost negligible effect on PC and proliferation [3]. Since endothelial cells are a key component of vasculature and are exposed to agents that are delivered systemically, it is important to determine the effect of Chk on endothelial cells in normal and tumor tissue. We have examined the proliferation and PC levels of human umbilical vein endothelial cells (HUVEC) after transient siRNA-chk transfection and compared the results with human breast cancer cells (MDA-MB-231).
MDA-MB-231 and HUVEC were used in this study. Cells were transiently transfected with 100 nM siRNA-chk for 48 hours using DhamaFECT. Cells were harvested to determine protein and mRNA levels at 48 hour post-transfection. Quantitative real-time PCR (q-RT-PCR) was performed to determine mRNA level using iQ SYBR Green Supermix and gene-specific primers in the iCycler real-time PCR detection system. Fully relaxed 1H MR spectra of water-soluble cell extracts were acquired on a Bruker Avance 500 MR spectrometer. PC level was quantified as mM using integrals of around 3.225 ppm signal in the 1H NMR spectra relative to cell number, cell volume (MDA-MB-231: 2050 µm3 and HUVEC: 4530 µm3), and an internal concentration standard. To exam the prolifelation/viability, cells were transfected with siRNA for 48 hours, changed to culture medium and cultured another 3 days, following which an MTS assay was performed.
After siRNA-chk transfection, Chk mRNA levels of MDA-MB-231 and HUVEC were comparable. Basal levels of Chk mRNA and Chk protein in HUVEC were low to start with, and it was difficult to downregulate Chk in HUVEC further. Immunoblot analysis showed significant downregulation of Chk protein in MDA-MB-231, and downregulation to a lesser extent in HUVEC after transfection of siRNA-chk. MTS assay result showed no significant reduction of proliferation in HUVEC after siRNA-chk transfection, while MDA-MB-231 showed a significant reduction of proliferation. The level of PC in HUVEC was about one tenth compared to MDA-MB-231. PC level was significantly reduced in MDA-MB-231 after siRNA-chk transfection but there was about 10% reduction in HUVEC. These data suggest that Chk inhibition will not affect endothelial cells during systemic administration, nor will it affect tumor vasculature.
[1] Glunde K et al, Cancer Res, 65, (2005); [2] Krishnamachary B et al, Cancer Res, 69, (2009); [3] Mori N et al, Cancer Res, 67, (2007).
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 980. doi:10.1158/1538-7445.AM2011-980
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Affiliation(s)
- Noriko Mori
- 1JHU ICMIC Program, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Mayur Gadiya
- 1JHU ICMIC Program, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Flonne Wildes
- 1JHU ICMIC Program, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Balaji Krishnamachary
- 1JHU ICMIC Program, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Zaver M. Bhujwalla
- 1JHU ICMIC Program, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD
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Shah T, Wildes F, Penet MF, Winnard PT, Glunde K, Artemov D, Ackerstaff E, Gimi B, Kakkad S, Raman V, Bhujwalla ZM. Choline kinase overexpression increases invasiveness and drug resistance of human breast cancer cells. NMR Biomed 2010; 23:633-42. [PMID: 20623626 PMCID: PMC3115627 DOI: 10.1002/nbm.1510] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
A direct correlation exists between increased choline kinase (Chk) expression, and the resulting increase of phosphocholine levels, and histological tumor grade. To better understand the function of Chk and choline phospholipid metabolism in breast cancer we have stably overexpressed one of the two isoforms of Chk-alpha known to be upregulated in malignant cells, in non-invasive MCF-7 human breast cancer cells. Dynamic tracking of cell invasion and cell metabolism were studied with a magnetic resonance (MR) compatible cell perfusion assay. The MR based invasion assay demonstrated that MCF-7 cells overexpressing Chk-alpha (MCF-7-Chk) exhibited an increase of invasion relative to control MCF-7 cells (0.84 vs 0.3). Proton MR spectroscopy studies showed significantly higher phosphocholine and elevated triglyceride signals in Chk overexpressing clones compared to control cells. A test of drug resistance in MCF-7-Chk cells revealed that these cells had an increased resistance to 5-fluorouracil and higher expression of thymidylate synthase compared to control MCF-7 cells. To further characterize increased drug resistance in these cells, we performed rhodamine-123 efflux studies to evaluate drug efflux pumps. MCF-7-Chk cells effluxed twice as much rhodamine-123 compared to MCF-7 cells. Chk-alpha overexpression resulted in MCF-7 human breast cancer cells acquiring an increasingly aggressive phenotype, supporting the role of Chk-alpha in mediating invasion and drug resistance, and the use of phosphocholine as a biomarker of aggressive breast cancers.
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Affiliation(s)
- Tariq Shah
- JHU ICMIC Program, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Flonne Wildes
- JHU ICMIC Program, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Marie-France Penet
- JHU ICMIC Program, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Paul T. Winnard
- JHU ICMIC Program, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Kristine Glunde
- JHU ICMIC Program, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Dmitri Artemov
- JHU ICMIC Program, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Ellen Ackerstaff
- JHU ICMIC Program, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, USA
- Memorial Sloan-Kettering Cancer Center 1275 York Ave., New York, NY
| | - Barjor Gimi
- JHU ICMIC Program, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, USA
- 708 Vail, Dartmouth Medical School, Hanover, NH, 03755
| | - Samata Kakkad
- JHU ICMIC Program, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Venu Raman
- JHU ICMIC Program, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Zaver M. Bhujwalla
- JHU ICMIC Program, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, USA
- Correspondence to: Z. M. Bhujwalla, Department of Radiology, The Johns Hopkins University School of Medicine, 208C Traylor Bldg, 720 Rutland Ave, Baltimore, MD 21205, USA.,
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Shah T, Krishnamachary B, Wildes F, Bhujwalla ZM. Abstract 451: HIF-1 alpha silencing in MDA-MB-231 human breast cancer cells alters choline phospholipid metabolism. Cancer Res 2010. [DOI: 10.1158/1538-7445.am10-451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Hypoxia-inducible factor-1 (HIF-1) over-expression has been associated with an increased patient mortality rate in many cancer types including breast cancer. Suppression of HIF-1 gene expression has been shown to inhibit tumor growth. Here we have studied the effect of HIF-1 silencing on the metabolism of MDA-MB-231 cells using a magnetic resonance (MR)- compatible cell perfusion assay. Previous studies have identified choline kinase (Chk), the enzyme that converts choline to phosphocholine (PC), and the resulting increase of PC and total choline (tCho) as markers of an aggressive phenotype. We found that HIF-1 silencing resulted in significantly reduced Chk expression together with reduced tCho and PC, compared to parental cells.
The sequence for shRNA against HIF-1α was cloned into a lentivirus vector with a green fluorescent protein (GFP) reporter construct (pRRL-pGK-GFP). Viral supernatant preparation and transduction of MDA-MB-231 breast cancer cells was performed following standard protocol. Transduced cells were validated for HIF-1α knock-down by western blots and by quantitative real-time polymerase chain reaction (q RT-PCR). Cell perfusion studies were performed using an MR-compatible perfusion assay to determine intracellular levels of metabolites using 1H and 31P MR spectroscopy (MRS). Experiments were performed in triplicates. The Mann Whitney-U test was used to determine statistical significance (p <0.05).
HIF-1α protein expression increased following treatment with 200μM of the hypoxia mimetic CoCl2 in parental MDA-MB-231 cells but not in cells transduced with HIF-1α shRNA. Reduced expression of Chk in HIF-1α silenced cells was observed following CoCl2 treatment, while its expression was induced in parental cells. Quantitative data from 1H and 31P MRS showed significantly reduced levels of tCho (p <0.05) and PC (p < 0.01) in HIF-1α silenced cells compared to parental MDA-MB-231 cells, confirming that silencing of HIF-1α reduced levels of choline containing metabolites by reducing Chk expression. We previously observed that Chk is up regulated under hypoxia and have established a HIF-1 binding site on the Chk promoter. The reduction of choline metabolites in HIF-1α silenced cells further confirms the role of HIF-1α in the regulation of Chk. The reduction of Chk, total choline and PC levels in HIF-1α silenced cells are also typical of a less aggressive metabolic phenotype.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 451.
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Affiliation(s)
- Tariq Shah
- 1JHU ICMIC Program, Russell H Morgan Department of Radiology and Radiological Sciences, Johns Hopkins School of Medicine, Baltimore, MD
| | - Balaji Krishnamachary
- 1JHU ICMIC Program, Russell H Morgan Department of Radiology and Radiological Sciences, Johns Hopkins School of Medicine, Baltimore, MD
| | - Flonne Wildes
- 1JHU ICMIC Program, Russell H Morgan Department of Radiology and Radiological Sciences, Johns Hopkins School of Medicine, Baltimore, MD
| | - Zaver M. Bhujwalla
- 1JHU ICMIC Program, Russell H Morgan Department of Radiology and Radiological Sciences, Johns Hopkins School of Medicine, Baltimore, MD
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Krishnamachary B, Glunde K, Wildes F, Mori N, Takagi T, Raman V, Bhujwalla ZM. Noninvasive detection of lentiviral-mediated choline kinase targeting in a human breast cancer xenograft. Cancer Res 2009; 69:3464-71. [PMID: 19336572 DOI: 10.1158/0008-5472.can-08-4120] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Elevated phosphocholine (PC) and total choline (tCho) metabolites are widely established characteristics of most cancer cells, including breast cancer. Effective silencing of choline kinase (chk), the enzyme that converts choline to PC, is associated with reduced tumor growth. The functional importance and down-regulation of chk using RNA interference has been previously established. Here, we report on the preclinical evaluation of lentiviral vector-mediated down-regulation of chk using short hairpin RNA (shRNA) in established tumors derived from human breast cancer cells. Concentrated lentivirus expressing shRNA against chk was injected i.v. in the tail vein of MDA-MB-231 tumor-bearing female severe combined immunodeficient mice. Transduction efficiency in cells and tumors in vivo was assessed optically by enhanced green fluorescent protein expression and additionally from chk mRNA and protein levels. An 80% reduction in chk mRNA and protein was achieved following approximately 90% transduction efficiency in cells. After transduction with chk-shRNA, (1)H magnetic resonance spectroscopy (MRS) of cell and tumor extracts showed decreases in PC and tCho levels (P < 0.01 and 0.05, respectively) in comparison with controls. PC levels were monitored noninvasively by (31)P MRS in tumors and by (1)H MRS in cell and tumor tissue extracts. Noninvasive (31)P MR spectra of chk-shRNA-transduced tumors in vivo showed lower PC and phosphomonoester levels that were associated with reduced tumor growth and proliferation. This study shows the use of lentiviral vectors to target chk in a human breast cancer xenograft and noninvasive MRS detection of this targeting.
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Affiliation(s)
- Balaji Krishnamachary
- Johns Hopkins University In Vivo Cellular Molecular Imaging Center Program, The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
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Li C, Wildes F, Winnard P, Artemov D, Penet MF, Bhujwalla ZM. Conjugation of Poly-l-lysine to Bacterial Cytosine Deaminase Improves the Efficacy of Enzyme/Prodrug Cancer Therapy. J Med Chem 2008; 51:3572-82. [DOI: 10.1021/jm800288h] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Cong Li
- JHU ICMIC Program, The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Flonne Wildes
- JHU ICMIC Program, The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Paul Winnard
- JHU ICMIC Program, The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Dmitri Artemov
- JHU ICMIC Program, The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Marie-France Penet
- JHU ICMIC Program, The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Zaver M. Bhujwalla
- JHU ICMIC Program, The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
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Stasinopoulos I, O'Brien DR, Wildes F, Glunde K, Bhujwalla ZM. Silencing of cyclooxygenase-2 inhibits metastasis and delays tumor onset of poorly differentiated metastatic breast cancer cells. Mol Cancer Res 2007; 5:435-42. [PMID: 17510310 DOI: 10.1158/1541-7786.mcr-07-0010] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Cyclooxygenases (COX) are rate-limiting enzymes involved in the conversion of PLA(2)-mobilized arachidonic acid into prostaglandins and thromboxanes. COX-2 is a key mediator of inflammation during both physiologic and pathologic responses to endogenous stimuli and infectious agents. Its overexpression has been detected in different cancers, including that of the breast. Using RNA interference, we have reduced the expression of COX-2 in the highly malignant breast cancer cell line MDA-MB-231 below detectable levels in response to interleukin-1 beta or 12-O-tetradecanoylphorbol-13-acetate treatment. Microarray analysis showed that COX-2 silencing resulted in the loss of mRNA expression of several oncogenic markers, such as matrix metalloproteinase-1, chemokine (C-X-C motif) receptor 4, and interleukin-11, which have been correlated with poor disease outcome, and in the up-regulation of antimetastatic transcripts, such as thrombospondin-1 and Epstein-Barr-Induced 3. Cells lacking COX-2 were less able to invade reconstituted extracellular matrix than parental cells in vitro. Consistent with these changes, loss of COX-2 resulted in the abolition or the significant delay of tumor onset when the cells were injected in the mammary fat pad of severe combined immunodeficient mice. Finally, silencing of COX-2 resulted in the inhibition of metastasis to the lungs of severe combined immunodeficient mice after intravenous injection. These data show that silencing of COX-2 abolishes the metastatic potential of MDA-MB-231 cells in vivo.
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Affiliation(s)
- Ioannis Stasinopoulos
- Department of Radiology, The Johns Hopkins University School of Medicine, Room 208C, Traylor Building, 720 Rutland Avenue, Baltimore, MD 21205, USA
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Mironchik Y, Winnard PT, Vesuna F, Kato Y, Wildes F, Pathak AP, Kominsky S, Artemov D, Bhujwalla Z, Van Diest P, Burger H, Glackin C, Raman V. Twist overexpression induces in vivo angiogenesis and correlates with chromosomal instability in breast cancer. Cancer Res 2006; 65:10801-9. [PMID: 16322226 PMCID: PMC5575828 DOI: 10.1158/0008-5472.can-05-0712] [Citation(s) in RCA: 221] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Aggressive cancer phenotypes are a manifestation of many different genetic alterations that promote rapid proliferation and metastasis. In this study, we show that stable overexpression of Twist in a breast cancer cell line, MCF-7, altered its morphology to a fibroblastic-like phenotype, which exhibited protein markers representative of a mesenchymal transformation. In addition, it was observed that MCF-7/Twist cells had increased vascular endothelial growth factor (VEGF) synthesis when compared with empty vector control cells. The functional changes induced by VEGF in vivo were analyzed by functional magnetic resonance imaging (MRI) of MCF-7/Twist-xenografted tumors. MRI showed that MCF-7/Twist tumors exhibited higher vascular volume and vascular permeability in vivo than the MCF-7/vector control xenografts. Moreover, elevated expression of Twist in breast tumor samples obtained from patients correlated strongly with high-grade invasive carcinomas and with chromosome instability, particularly gains of chromosomes 1 and 7. Taken together, these results show that Twist overexpression in breast cancer cells can induce angiogenesis, correlates with chromosomal instability, and promotes an epithelial-mesenchymal-like transition that is pivotal for the transformation into an aggressive breast cancer phenotype.
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Affiliation(s)
- Yelena Mironchik
- Department of Radiology, Johns Hopkins University, School of Medicine, Baltimore, Maryland
| | - Paul T. Winnard
- Department of Radiology, Johns Hopkins University, School of Medicine, Baltimore, Maryland
| | - Farhad Vesuna
- Department of Radiology, Johns Hopkins University, School of Medicine, Baltimore, Maryland
| | - Yoshinori Kato
- Department of Radiology, Johns Hopkins University, School of Medicine, Baltimore, Maryland
| | - Flonne Wildes
- Department of Radiology, Johns Hopkins University, School of Medicine, Baltimore, Maryland
| | - Arvind P. Pathak
- Department of Radiology, Johns Hopkins University, School of Medicine, Baltimore, Maryland
| | - Scott Kominsky
- Department of Orthopedic Surgery, Johns Hopkins University, School of Medicine, Baltimore, Maryland
| | - Dmitri Artemov
- Department of Radiology, Johns Hopkins University, School of Medicine, Baltimore, Maryland
| | - Zaver Bhujwalla
- Department of Radiology, Johns Hopkins University, School of Medicine, Baltimore, Maryland
| | - Paul Van Diest
- Department of Pathology, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Horst Burger
- Institute of Pathology, University of Munster, Munster, Germany
| | - Carlotta Glackin
- Division of Molecular Medicine, Beckman Research Institute, City of Hope, Duarte, California
| | - Venu Raman
- Department of Radiology, Johns Hopkins University, School of Medicine, Baltimore, Maryland
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Glunde K, Foss CA, Takagi T, Wildes F, Bhujwalla ZM. Synthesis of 6'-O-lissamine-rhodamine B-glucosamine as a novel probe for fluorescence imaging of lysosomes in breast tumors. Bioconjug Chem 2005; 16:843-51. [PMID: 16029026 DOI: 10.1021/bc050046n] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Lysosomes contain multiple proteases, which play a crucial role in breast cancer invasion and metastasis. Noninvasive labeling of lysosomes in breast cancer cells and solid breast tumor models is therefore useful to study lysosomal trafficking and its role in invasion. We have synthesized a novel compound, 6'-O-lissamine-rhodamine B-glucosamine, to fluorescently label lysosomes, and evaluated the compound in human breast cancer cells in cell culture or in orthotopic human breast cancer models. We demonstrated that this novel compound biosynthetically labeled lysosomal proteins following addition to cell culture medium or following intravenous injection into mouse models of breast cancer. Fluorescence from 6'-O-lissamine-rhodamine B-glucosamine colocalized with several well-established lysosomal markers, such as lysosome-associated proteins 1 and 2 (LAMP-1 and -2) and CD63. We also demonstrated the feasibility of performing in vivo fluorescence imaging of 6'-O-lissamine-rhodamine B-glucosamine to image lysosomes in human breast cancer models.
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Affiliation(s)
- Kristine Glunde
- JHU ICMIC Program, The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.
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Abstract
The homeotic gene HOXA5 has been shown to play an important role in breast tumorigenesis. We have shown that loss of p53 correlated with loss of a developmentally regulated transcription factor, HOXA5, in primary breast cancer. Searching for potential protein interacting partners we found that HOXA5 binds to an anti-apoptotic protein, Twist. Furthermore, Twist-overexpressing MCF-7 cells displayed a deregulated p53 response to gamma-radiation and decreased regulation of downstream target genes. Using a p53-promoter-reporter system, we demonstrated that HOXA5 could partially restore the inhibitory effects of Twist on p53 target genes. These effects are likely mediated through both the transcriptional up-regulation of p53 and the protein-protein interaction between HOXA5 and Twist. Thus, the loss of HOXA5 expression could lead to the functional activation of Twist resulting in aberrant cell cycle regulation and promoting breast carcinogenesis.
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Affiliation(s)
- Ioannis A Stasinopoulos
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
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