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Xie X, Lee J, Iwase T, Kai M, Ueno NT. Emerging drug targets for triple-negative breast cancer: A guided tour of the preclinical landscape. Expert Opin Ther Targets 2022; 26:405-425. [PMID: 35574694 DOI: 10.1080/14728222.2022.2077188] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
INTRODUCTION Triple-negative breast cancer (TNBC) is the most fatal molecular subtype of breast cancer because of its aggressiveness and resistance to chemotherapy. FDA-approved therapies for TNBC are limited to poly(ADP-ribose) polymerase inhibitors, immune checkpoint inhibitors, and trophoblast cell surface antigen 2-targeted antibody-drug conjugate. Therefore, developing a novel effective targeted therapy for TNBC is an urgent unmet need. AREAS COVERED In this narrative review, we discuss emerging targets for TNBC treatment discovered in early translational studies. We focus on cancer cell membrane molecules, hyperactive intracellular signaling pathways, and the tumor microenvironment (TME) based on their druggability, therapeutic potency, specificity to TNBC, and application in immunotherapy. EXPERT OPINION The significant challenges in the identification and validation of TNBC-associated targets are 1) application of appropriate genetic, molecular, and immunological approaches for modulating the target, 2) establishment of a proper mouse model that accurately represents the human immune TME, 3) TNBC molecular heterogeneity, and 4) failure translation of preclinical findings to clinical practice. To overcome those difficulties, future research needs to apply novel technology, such as single-cell RNA sequencing, thermostable group II intron reverse transcriptase sequencing, and humanized mouse models. Further, combination treatment targeting multiple pathways in both the TNBC tumor and its TME is essential for effective disease control.
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Affiliation(s)
- Xuemei Xie
- Section of Translational Breast Cancer Research, Morgan Welch Inflammatory Breast Cancer Research Program and Clinic, Department of Breast Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Jangsoon Lee
- Section of Translational Breast Cancer Research, Morgan Welch Inflammatory Breast Cancer Research Program and Clinic, Department of Breast Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Toshiaki Iwase
- Section of Translational Breast Cancer Research, Morgan Welch Inflammatory Breast Cancer Research Program and Clinic, Department of Breast Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Megumi Kai
- Section of Translational Breast Cancer Research, Morgan Welch Inflammatory Breast Cancer Research Program and Clinic, Department of Breast Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Naoto T Ueno
- Section of Translational Breast Cancer Research, Morgan Welch Inflammatory Breast Cancer Research Program and Clinic, Department of Breast Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
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Abstract
PURPOSE OF REVIEW Apoptosis is a major mechanism of cancer cell death. Thus, evasion of apoptosis results in therapy resistance. Here, we review apoptosis modulators in cancer and their recent developments, including MDM2 inhibitors and kinase inhibitors that can induce effective apoptosis. RECENT FINDINGS Both extrinsic pathways (external stimuli through cell surface death receptor) and intrinsic pathways (mitochondrial-mediated regulation upon genotoxic stress) regulate the complex process of apoptosis through orchestration of various proteins such as members of the BCL-2 family. Dysregulation within these complex steps can result in evasion of apoptosis. However, via the combined evolution of medicinal chemistry and molecular biology, omics assays have led to innovative inducers of apoptosis and inhibitors of anti-apoptotic regulators. Many of these agents are now being tested in cancer patients in early-phase trials. We believe that despite a sluggish speed of development, apoptosis targeting holds promise as a relevant strategy in cancer therapeutics.
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Kumari M, Krishnamurthy PT, Sola P. Targeted Drug Therapy to Overcome Chemoresistance in Triple-negative Breast Cancer. Curr Cancer Drug Targets 2021; 20:559-572. [PMID: 32370716 DOI: 10.2174/1568009620666200506110850] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Revised: 03/09/2020] [Accepted: 03/16/2020] [Indexed: 02/07/2023]
Abstract
Triple-negative Breast Cancer (TNBC) is the most aggressive and prevailing breast cancer subtype. The chemotherapeutics used in the treatment of TNBC suffer from chemoresistance, dose-limiting toxicities and off-target side effects. As a result, conventional chemotherapeutics are unable to prevent tumor growth, metastasis and result in failure of therapy. Various new targets such as BCSCs surface markers (CD44, CD133, ALDH1), signaling pathways (IL-6/JAK/STAT3, notch), pro and anti-apoptotic proteins (Bcl-2, Bcl-xL, DR4, DR5), hypoxic factors (HIF-1α, HIF-2α) and drug efflux transporters (ABCC1, ABCG2 and ABCB1) have been exploited to treat TNBC. Further, to improve the efficacy and safety of conventional chemotherapeutics, researchers have tried to deliver anticancer agents specifically to the TNBCs using nanocarrier based drug delivery. In this review, an effort has been made to highlight the various factors responsible for the chemoresistance in TNBC, novel molecular targets of TNBC and nano-delivery systems employed to achieve sitespecific drug delivery to improve efficacy and reduce off-target side effects.
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Affiliation(s)
- Mamta Kumari
- Department of Pharmacology, JSS College of Pharmacy, (A Constituent College of JSS Academy of Higher Education & Research), Ooty, Tamilnadu, India
| | - Praveen Thaggikuppe Krishnamurthy
- Department of Pharmacology, JSS College of Pharmacy, (A Constituent College of JSS Academy of Higher Education & Research), Ooty, Tamilnadu, India
| | - Piyong Sola
- Department of Pharmacology, JSS College of Pharmacy, (A Constituent College of JSS Academy of Higher Education & Research), Ooty, Tamilnadu, India
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DR5 antibody conjugated lipid-based nanocarriers of gamma-secretase inhibitor for the treatment of triple negative breast cancer. Chem Phys Lipids 2020; 235:105033. [PMID: 33385372 DOI: 10.1016/j.chemphyslip.2020.105033] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 11/24/2020] [Accepted: 12/20/2020] [Indexed: 12/21/2022]
Abstract
In the present study, Death receptor-5 (DR5) antibody conjugated solid lipid nanoparticles (DR5-DAPT-SLNs) has been formulated for effective intracellular of γ-secretase inhibitor, N-[N-(3,5-Difluorophenacetyl)-l-alanyl]-S-phenylglycine t-butyl ester (DAPT) to cancer cells. Emulsification-solvent evaporation, followed by EDC cross-linking methods, was employed to prepare DR5 targeted DAPT-SLNs (DR5-DAPT-SLNs). The formulation was characterized by its particle size, shape, and surface charge. The in vitro & in vivo anticancer efficacy was studied in MDA-MB231 triple negative breast cancer (TNBC) cells and DMBA induced breast cancer model in mice, respectively. The results show that thatDR5-DAPT-SLNs is found to be a spherical shape with an average particle size of 187 ± 0.98 nm and having an average surface charge of 23 ± 2.3 mV. DR5-DAPT-SLNs have higher cytotoxicity in MDA-MB231 cells compared to DAPT-SLNs (non-targeted) and the bulk drug. However, in DR5 negative HEK 293 noncancer cells, the formulation shows minimal cytotoxic effects. The above results, therefore, demonstrate DR5 mediated uptake is responsible for improved cytotoxicity of DAPT. In the in vivo anticancer study, DR5-DAPT-SLNs show greater tumor regression when compared to DAPT-SLNs and the bulk drug. In conclusion, the results of the present study demonstrate that the DR5-DAPT-SLNs selectively target cancer cells and potentiate the anticancer efficacy of DAPT against TNBC cells.
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Pindiprolu SKSS, Krishnamurthy PT, Chintamaneni PK. Pharmacological targets of breast cancer stem cells: a review. Naunyn Schmiedebergs Arch Pharmacol 2018; 391:463-479. [PMID: 29476201 DOI: 10.1007/s00210-018-1479-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 02/13/2018] [Indexed: 02/07/2023]
Abstract
Breast cancers contain small population of tumor-initiating cells called breast cancer stem cells (BCSCs), which are spared even after chemotherapy. Recently, BCSCs are implicated to be a cause of metastasis, tumor relapse, and therapy resistance in breast cancer. BCSCs have unique molecular mechanisms, which can be targeted to eliminate them. These include surface biomarkers, proteins involved in self-renewal pathways, drug efflux transporters, apoptotic/antiapoptotic proteins, autophagy, metabolism, and microenvironment regulation. The complex molecular mechanisms behind the survival of BCSCs and pharmacological targets for elimination of BCSCs are described in this review.
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Affiliation(s)
- Sai Kiran S S Pindiprolu
- Department of Pharmacology, JSS College of Pharmacy (Jagadguru Sri Shivarathreeshwara University), Rocklands, Udhagamandalam, Tamil Nadu, 643001, India
| | - Praveen T Krishnamurthy
- Department of Pharmacology, JSS College of Pharmacy (Jagadguru Sri Shivarathreeshwara University), Rocklands, Udhagamandalam, Tamil Nadu, 643001, India.
| | - Pavan Kumar Chintamaneni
- Department of Pharmacology, JSS College of Pharmacy (Jagadguru Sri Shivarathreeshwara University), Rocklands, Udhagamandalam, Tamil Nadu, 643001, India
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Pindiprolu SKSS, Krishnamurthy PT, Chintamaneni PK, Karri VVSR. Nanocarrier based approaches for targeting breast cancer stem cells. ARTIFICIAL CELLS NANOMEDICINE AND BIOTECHNOLOGY 2017; 46:885-898. [PMID: 28826237 DOI: 10.1080/21691401.2017.1366337] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Breast cancer stem cells (BCSCs) are heterogeneous subpopulation of tumour initiating cells within breast tumours. They are spared even after chemotherapy and responsible for tumour relapse. Targeting BCSCs is, therefore, necessary to achieve radical cure in breast cancer. Despite the availability of agents targeting BCSCs, their clinical application is limited due to their off-target effects and bioavailability issues. Nanotechnology based drug carriers (nanocarriers) offer various advantages to deliver anti-BCSCs agents specifically to their target sites by overcoming their bioavailability issues. In this review, we describe various strategies for targeting BCSCs using nanocarriers.
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Affiliation(s)
- Sai Kiran S S Pindiprolu
- a Department of Pharmacology , JSS College of Pharmacy (A Constituent College of Jagadguru Sri Shivarathreeshwara University) , Ootacamund , Tamil Nadu , India
| | - Praveen T Krishnamurthy
- a Department of Pharmacology , JSS College of Pharmacy (A Constituent College of Jagadguru Sri Shivarathreeshwara University) , Ootacamund , Tamil Nadu , India
| | - Pavan Kumar Chintamaneni
- a Department of Pharmacology , JSS College of Pharmacy (A Constituent College of Jagadguru Sri Shivarathreeshwara University) , Ootacamund , Tamil Nadu , India
| | - Veera Venkata Satyanarayana Reddy Karri
- b Department of Pharmaceutics , JSS College of Pharmacy (A Constituent College of Jagadguru Sri Shivarathreeshwara University) , Ootacamund , Tamil Nadu , India
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Rico MJ, Perroud HA, Herrera C, Alasino CM, Roggero EA, Pezzotto SM, Nocito AL, Rozados VR, Scharovsky OG. Putative Biomarkers of Response to Treatment in Breast Cancer Patients: A Pilot Assay. Cancer Invest 2017; 35:377-385. [DOI: 10.1080/07357907.2017.1309545] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- María J. Rico
- Institute of Experimental Genetics, School of Medicine, National University of Rosario, Rosario, Argentina
- National Scientific and Technological Research Council (CONICET), Rosario, Argentina
| | - Herman A. Perroud
- Institute of Experimental Genetics, School of Medicine, National University of Rosario, Rosario, Argentina
- National Scientific and Technological Research Council (CONICET), Rosario, Argentina
| | - Cintia Herrera
- Institute of Experimental Genetics, School of Medicine, National University of Rosario, Rosario, Argentina
| | | | - Eduardo A. Roggero
- Institute of Experimental Genetics, School of Medicine, National University of Rosario, Rosario, Argentina
| | - Stella M. Pezzotto
- Institute of Immunology, School of Medical Sciences, National University of Rosario, Rosario, Argentina
- National University of Rosario Research Council (CIUNR), Rosario, Argentina
| | - Ana Lía Nocito
- Department of Pathological Anatomy and Physiology, School of Medical Sciences, National University of Rosario, Rosario, Argentina
| | - Viviana R. Rozados
- Institute of Experimental Genetics, School of Medicine, National University of Rosario, Rosario, Argentina
| | - O. Graciela Scharovsky
- Institute of Experimental Genetics, School of Medicine, National University of Rosario, Rosario, Argentina
- National Scientific and Technological Research Council (CONICET), Rosario, Argentina
- National University of Rosario Research Council (CIUNR), Rosario, Argentina
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Eng JWL, Mace TA, Sharma R, Twum DYF, Peng P, Gibbs JF, Pitoniak R, Reed CB, Abrams SI, Repasky EA, Hylander BL. Pancreatic cancer stem cells in patient pancreatic xenografts are sensitive to drozitumab, an agonistic antibody against DR5. J Immunother Cancer 2016; 4:33. [PMID: 27330806 PMCID: PMC4915140 DOI: 10.1186/s40425-016-0136-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 05/16/2016] [Indexed: 02/07/2023] Open
Abstract
Background Therapeutic resistance and tumor recurrence are two major hurdles in the treatment of pancreatic ductal adenocarcinoma. Recent findings suggest that both of these attributes are associated with a small subset of pancreatic tumor initiating cancer stem cells (CSCs). Here, we demonstrate that drozitumab, a human agonistic monoclonal antibody which binds the death receptor DR5, selectively eliminates CSCs, resulting in tumor growth inhibition and even regression of pancreatic tumors. Methods To examine the efficacy of drozitumab against pancreatic CSCs, we treated patient-derived pancreatic tumor xenografts (PDX) in immunocompromised SCID mice and evaluated tumor control. To assess apoptosis following drozitumab treatment, we identified the CSCs as CD24+, CD44+, and EpCAM+ by FACS analysis, and measured in vivo and in vitro levels of cleaved caspase-3. Lastly, in vitro evaluation of DR5 re-expression was performed using isolated patient pancreatic cancer xenograft cells along with the cell line, Panc-1. After treatment with drozitumab, the remaining DR5- cells were assessed by FACS analysis for DR5 expression at the cell surface at 8, 24 and 48 h post-treatment. All in vivo growth data was analyzed by 2-way Anova, incidence data was analyzed using Mantel-Cox, and in vitro studies statistics were performed with a t-test. Results We find that while 75–100 % of CSCs express DR5, only 25 % of bulk tumor cells express the death receptors at any one time. Consequently, drozitumab treatment of SCID mice bearing PDX kills higher percentages of CSCs than bulk tumor cells. Additionally, SCID mice implanted with isolated CSCs and then immediately treated with drozitumab fail to ever develop tumors. In vitro studies demonstrate that while drozitumab treatment reduces the DR5+ cell population, the remaining tumor cells begin to express DR5, suggesting a mechanism by which continuous administration of drozitumab can ultimately result in tumor regression despite the initially low percentage of DR5+ cells. Conclusions Overall, our work reveals that treatment of pancreatic tumors with the drozitumab can lead to long-term tumor control by targeting both bulk cells and CSCs. Electronic supplementary material The online version of this article (doi:10.1186/s40425-016-0136-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jason W-L Eng
- Department of Immunology, Roswell Park Cancer Institute, Buffalo, NY 14263 USA
| | - Thomas A Mace
- Department of Immunology, Roswell Park Cancer Institute, Buffalo, NY 14263 USA.,Present Address: Division of Medical Oncology, Department Internal Medicine, The Ohio State University, Columbus, OH 43210 USA
| | - Rohit Sharma
- Department of Surgical Oncology, Roswell Park Cancer Institute, Buffalo, 14263 NY USA.,Present Address: Department of Surgery, Lehigh Valley Physician Group, Allentown, 18103 PA USA
| | - Danielle Y F Twum
- Department of Immunology, Roswell Park Cancer Institute, Buffalo, NY 14263 USA
| | - Peng Peng
- Department of Immunology, Roswell Park Cancer Institute, Buffalo, NY 14263 USA
| | - John F Gibbs
- Department of Surgical Oncology, Roswell Park Cancer Institute, Buffalo, 14263 NY USA.,Present address: Department of Surgery Chief of Surgical Oncology, Jersey Shore University Medical Center, 1945 State Highway 33, Neptune, NJ 07753 USA
| | - Rosemarie Pitoniak
- Department of Immunology, Roswell Park Cancer Institute, Buffalo, NY 14263 USA
| | - Chelsey B Reed
- Department of Immunology, Roswell Park Cancer Institute, Buffalo, NY 14263 USA
| | - Scott I Abrams
- Department of Immunology, Roswell Park Cancer Institute, Buffalo, NY 14263 USA
| | - Elizabeth A Repasky
- Department of Immunology, Roswell Park Cancer Institute, Buffalo, NY 14263 USA
| | - Bonnie L Hylander
- Department of Immunology, Roswell Park Cancer Institute, Buffalo, NY 14263 USA
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French R, Hayward O, Jones S, Yang W, Clarkson R. Cytoplasmic levels of cFLIP determine a broad susceptibility of breast cancer stem/progenitor-like cells to TRAIL. Mol Cancer 2015; 14:209. [PMID: 26667821 PMCID: PMC4678708 DOI: 10.1186/s12943-015-0478-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 12/03/2015] [Indexed: 01/05/2023] Open
Abstract
Background The clinical application of TRAIL receptor agonists as a novel cancer therapy has been tempered by heterogeneity in tumour responses. This is illustrated in breast cancer, where TRAIL is cytotoxic in cell lines of mesenchymal origin but refractory in lines with an epithelial-like phenotype. However, it is now evident that intra-tumour heterogeneity includes a minority subpopulation of tumour-initiating stem/progenitor-like cells (CSCs) that possess mesenchymal characteristics. We hypothesised therefore that TRAIL may target these phenotypically distinct CSC-like cells that are common to most - if not all - breast cancers, thus impacting on the source of malignancy in a much broader range of breast tumour subtypes than previously envisaged. Methods We used colony formation, tumoursphere, flow cytometry and xenograft tumour initiation assays to observe the TRAIL sensitivity of CSC-like cells in a panel of two mesenchymal-like (TRAIL-sensitive) and four epithelial-like (TRAIL-resistant) breast cancer cell lines. Subcellular levels of the endogenous TRAIL inhibitor, cFLIP, were determined by western blot and immunofluorescence microscopy. The effect of the subcellular redistribution of cFLIP on TRAIL sensitivity and Wnt signalling was determined using cFLIP localisation mutants and the TOPFlash reporter assay respectively. Results TRAIL universally suppressed the clonal expansion of stem/progenitors in all six of the breast cancer cell lines tested, irrespective of their phenotype or overall sensitivity to TRAIL. A concomitant reduction in tumour initiation was confirmed in the TRAIL-resistant epithelial cell line, MCF-7, following serial dilution xenotransplantation. Furthermore TRAIL sensitivity of breast CSCs was inversely proportional to the relative cytoplasmic levels of cFLIP while overexpression of cFLIP in the cytosol using subcellular localization mutants of cFLIP protected these cells from cytotoxicity. The accumulation of nuclear cFLIP on the other hand did not influence TRAIL cytotoxicity but instead promoted Wnt-dependent signalling. Conclusion These data propose a novel role for TRAIL as a selective CSC agent with a broad specificity for both epithelial and mesenchymal breast tumour subtypes. Furthermore we identify a dual role for cFLIP in the maintenance of breast CSC viability, dependent upon its subcellular distribution. Electronic supplementary material The online version of this article (doi:10.1186/s12943-015-0478-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Rhiannon French
- European Cancer Stem Cell Research Institute Cardiff University School of Biosciences, Haydn Ellis Building, Maindy Road, Cardiff, CF24 4HQ, UK.
| | - Olivia Hayward
- European Cancer Stem Cell Research Institute Cardiff University School of Biosciences, Haydn Ellis Building, Maindy Road, Cardiff, CF24 4HQ, UK.
| | - Samuel Jones
- European Cancer Stem Cell Research Institute Cardiff University School of Biosciences, Haydn Ellis Building, Maindy Road, Cardiff, CF24 4HQ, UK.
| | - William Yang
- European Cancer Stem Cell Research Institute Cardiff University School of Biosciences, Haydn Ellis Building, Maindy Road, Cardiff, CF24 4HQ, UK.
| | - Richard Clarkson
- European Cancer Stem Cell Research Institute Cardiff University School of Biosciences, Haydn Ellis Building, Maindy Road, Cardiff, CF24 4HQ, UK.
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Zhang M, Shi C, Xia C, Yang J, Niu X, Zhuang G, Yin P. Anti-DR5 mAb inhibits proliferation of human fibroblast-like synovial cells and reduces their cytokine secretion in vitro. Onco Targets Ther 2015; 8:2745-55. [PMID: 26491348 PMCID: PMC4599060 DOI: 10.2147/ott.s87448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND We have previously reported that anti-death receptor 5 (DR5) monoclonal antibody (mAb) is therapeutically effective in the treatment of rheumatoid arthritis (RA) in a collagen-induced arthritis rat model. However, the molecular mechanism and the effect of anti-DR5 mAb on proapoptotic genes and cytokine secretion in the human fibroblast-like synovial cells (FLS) requires further clarification. This study may provide new evidence for the application of anti-DR5 mAb as a treatment for RA. METHODS Human FLS were isolated from patients with RA and were treated with anti-DR5 mAb. An MTT assay and flow cytometry were used to detect the induction of apoptosis in vitro. Cytokine secretion by the FLS was detected using the enzyme-linked immunosorbent assay. The mRNA expression was assessed by reverse transcription polymerase chain reaction, and the protein expression was analyzed by Western blot. The apoptotic pathway was investigated further using a caspase inhibition assay. RESULTS Anti-DR5 mAb-induced apoptosis in human RA FLS in vitro. The protein expressions of caspase-8, -3, and -9 were decreased in human anti-DR5 mAb-treated FLS in a dose-dependent manner through exposure to a caspase inhibitor, indicating that anti-DR5 mAb induction of apoptosis is through the caspase pathway. Decreased levels of tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) were detected after treatment with anti-DR5 mAb in vitro. CONCLUSION Anti-DR5 mAb may induce apoptosis in human FLS through the caspase pathway and through decreased secretions of TNF-α and IFN-γ.
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Affiliation(s)
- Minping Zhang
- Organ Transplantation Institute, Anti-Cancer Research Center, Medical College, Xiamen University, Xiamen, People's Republic of China ; The Department of Pharmacy, First Hospital, Nanping, People's Republic of China
| | - Chunyan Shi
- Organ Transplantation Institute, Anti-Cancer Research Center, Medical College, Xiamen University, Xiamen, People's Republic of China
| | - Chun Xia
- The Department of Orthopaedics, Xiamen University, Xiamen, Fujian, People's Republic of China
| | - Jin Yang
- Organ Transplantation Institute, Anti-Cancer Research Center, Medical College, Xiamen University, Xiamen, People's Republic of China
| | - Xingyang Niu
- Organ Transplantation Institute, Anti-Cancer Research Center, Medical College, Xiamen University, Xiamen, People's Republic of China
| | - Guohong Zhuang
- Organ Transplantation Institute, Anti-Cancer Research Center, Medical College, Xiamen University, Xiamen, People's Republic of China
| | - Ping Yin
- The Department of Pathology, Xiamen Zhongshan Hospital, Xiamen University, Xiamen, Fujian, People's Republic of China
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Wang YH, Scadden DT. Harnessing the apoptotic programs in cancer stem-like cells. EMBO Rep 2015; 16:1084-98. [PMID: 26253117 DOI: 10.15252/embr.201439675] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Accepted: 06/19/2015] [Indexed: 12/12/2022] Open
Abstract
Elimination of malignant cells is an unmet challenge for most human cancer types even with therapies targeting specific driver mutations. Therefore, a multi-pronged strategy to alter cancer cell biology on multiple levels is increasingly recognized as essential for cancer cure. One such aspect of cancer cell biology is the relative apoptosis resistance of tumor-initiating cells. Here, we provide an overview of the mechanisms affecting the apoptotic process in tumor cells emphasizing the differences in the tumor-initiating or stem-like cells of cancer. Further, we summarize efforts to exploit these differences to design therapies targeting that important cancer cell population.
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Affiliation(s)
- Ying-Hua Wang
- Center for Regenerative Medicine and Cancer Center, Massachusetts General Hospital, Boston, MA, USA Harvard Stem Cell Institute, Cambridge, MA, USA Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA, USA
| | - David T Scadden
- Center for Regenerative Medicine and Cancer Center, Massachusetts General Hospital, Boston, MA, USA Harvard Stem Cell Institute, Cambridge, MA, USA Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA, USA
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Forero-Torres A, Varley KE, Abramson VG, Li Y, Vaklavas C, Lin NU, Liu MC, Rugo HS, Nanda R, Storniolo AM, Traina TA, Patil S, Van Poznak CH, Nangia JR, Irvin WJ, Krontiras H, De Los Santos JF, Haluska P, Grizzle W, Myers RM, Wolff AC. TBCRC 019: A Phase II Trial of Nanoparticle Albumin-Bound Paclitaxel with or without the Anti-Death Receptor 5 Monoclonal Antibody Tigatuzumab in Patients with Triple-Negative Breast Cancer. Clin Cancer Res 2015; 21:2722-9. [PMID: 25779953 DOI: 10.1158/1078-0432.ccr-14-2780] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 02/21/2015] [Indexed: 12/31/2022]
Abstract
PURPOSE Tigatuzumab (TIG), an agonistic anti-DR5 antibody, triggers apoptosis in DR5(+) human tumor cells without crosslinking. TIG has strong in vitro/in vivo activity against basal-like breast cancer cells enhanced by chemotherapy agents. This study evaluates activity of TIG and chemotherapy in patients with metastatic triple-negative breast cancer (TNBC). EXPERIMENTAL DESIGN Randomized 2:1 phase II trial of albumin-bound paclitaxel (nab-PAC) ± TIG in patients with TNBC stratified by prior chemotherapy. Patients received nab-PAC weekly × 3 ± TIG every other week, every 28 days. Primary objective was within-arm objective response rate (ORR). Secondary objectives were safety, progression-free survival (PFS), clinical benefit, and TIG immunogenicity. Metastatic research biopsies were required. RESULTS Among 64 patients (60 treated; TIG/nab-PAC n = 39 and nab-PAC n = 21), there were 3 complete remissions (CR), 8 partial remissions (PR; 1 almost CR), 11 stable diseases (SD), and 17 progressive diseases (PD) in the TIG/nab-PAC arm (ORR, 28%), and no CRs, 8 PRs, 4 SDs, and 9 PDs in the nab-PAC arm (ORR, 38%). There was a numerical increase in CRs and several patients had prolonged PFS (1,025+, 781, 672, 460, 334) in the TIG/nab-PAC arm. Grade 3 toxicities were 28% and 29%, respectively, with no grade 4-5. Exploratory analysis suggests an association of ROCK1 gene pathway activation with efficacy in the TIG/nab-PAC arm. CONCLUSIONS ORR and PFS were similar in both. Preclinical activity of TIG in basal-like breast cancer and prolonged PFS in few patients in the combination arm support further investigation of anti-DR5 agents. ROCK pathway activation merits further evaluation.
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Affiliation(s)
| | | | | | - Yufeng Li
- University of Alabama at Birmingham, Birmingham, Alabama
| | | | - Nancy U Lin
- Dana-Farber Cancer Institute, Boston, Massachusetts
| | - Minetta C Liu
- Georgetown University Hospital, Washington, District of Columbia
| | - Hope S Rugo
- University of California, San Francisco Helen Diller Family Comprehensive Cancer Center, San Francisco, California
| | - Rita Nanda
- The University of Chicago, Chicago, Illinois
| | - Anna M Storniolo
- Indiana University Melvin and Bren Simon Cancer Center, Indianapolis, Indiana
| | | | - Sujata Patil
- Memorial Sloan-Kettering Cancer Center, New York, New York
| | | | | | | | | | | | - Paul Haluska
- Mayo Clinic College of Medicine, Rochester, Minnesota
| | | | - Richard M Myers
- HudsonAlpha Institute for Biotechnology, Huntsville, Alabama
| | - Antonio C Wolff
- Johns Hopkins Kimmel Comprehensive Cancer Center, Baltimore, Maryland
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Prabhu VV, Allen JE, Dicker DT, El-Deiry WS. Small-Molecule ONC201/TIC10 Targets Chemotherapy-Resistant Colorectal Cancer Stem-like Cells in an Akt/Foxo3a/TRAIL-Dependent Manner. Cancer Res 2015; 75:1423-32. [PMID: 25712124 DOI: 10.1158/0008-5472.can-13-3451] [Citation(s) in RCA: 110] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Accepted: 01/30/2015] [Indexed: 01/05/2023]
Abstract
Self-renewing colorectal cancer stem/progenitor cells (CSC) contribute to tumor maintenance and resistance to therapy. Therapeutic targeting of CSCs could improve treatment response and prolong patient survival. ONC201/TIC10 is a first-in-class antitumor agent that induces TRAIL pathway-mediated cell death in cancer cells without observed toxicity. We have previously described that ONC201/TIC10 exposure leads to transcriptional induction of the TRAIL gene via transcription factor Foxo3a, which is activated by dual inactivation of Akt and ERK. The Akt and ERK pathways serve as important targets in CSCs. Foxo3a is a key mediator of Akt and ERK-mediated CSC regulation. We hypothesized that the potent antitumor effect of ONC201/TIC10 in colorectal cancer involves targeting CSCs and bulk tumor cells. ONC201/TIC10 depletes CD133(+), CD44(+), and Aldefluor(+) cells in vitro and in vivo. TIC10 significantly inhibits colonosphere formation of unsorted and sorted 5-fluorouracil-resistant CSCs. ONC201/TIC10 significantly reduces CSC-initiated xenograft tumor growth in mice and prevents the passage of these tumors. ONC201/TIC10 treatment also decreased xenograft tumor initiation and was superior to 5-fluorouracil treatment. Thus, ONC201/TIC10 inhibits CSC self-renewal in vitro and in vivo. ONC201/TIC10 inhibits Akt and ERK, consequently activating Foxo3a and significantly induces cell surface TRAIL and DR5 expression in both CSCs and non-CSCs. ONC201/TIC10-mediated anti-CSC effect is significantly blocked by the TRAIL sequestering antibody RIK-2. Overexpression of Akt, DR5 knockdown, and Foxo3a knockdown rescues ONC201/TIC10-mediated depletion of CD44(+) cells and colonosphere inhibition. In conclusion, ONC201/TIC10 is a promising agent for colorectal cancer therapy that targets both non-CSCs and CSCs in an Akt-Foxo3a-TRAIL-dependent manner.
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Affiliation(s)
- Varun V Prabhu
- Penn State Hershey Cancer Institute, Department of Medicine (Hematology/Oncology), Penn State College of Medicine, Hershey, Pennsylvania. Laboratory of Translational Oncology and Experimental Cancer Therapeutics, Department of Medical Oncology and Molecular Therapeutics Program, Fox Chase Cancer Center, Philadelphia, Pennsylvania
| | | | - David T Dicker
- Penn State Hershey Cancer Institute, Department of Medicine (Hematology/Oncology), Penn State College of Medicine, Hershey, Pennsylvania. Laboratory of Translational Oncology and Experimental Cancer Therapeutics, Department of Medical Oncology and Molecular Therapeutics Program, Fox Chase Cancer Center, Philadelphia, Pennsylvania
| | - Wafik S El-Deiry
- Penn State Hershey Cancer Institute, Department of Medicine (Hematology/Oncology), Penn State College of Medicine, Hershey, Pennsylvania. Laboratory of Translational Oncology and Experimental Cancer Therapeutics, Department of Medical Oncology and Molecular Therapeutics Program, Fox Chase Cancer Center, Philadelphia, Pennsylvania.
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14
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Maccalli C, De Maria R. Cancer stem cells: perspectives for therapeutic targeting. Cancer Immunol Immunother 2015; 64:91-7. [PMID: 25104304 PMCID: PMC11028671 DOI: 10.1007/s00262-014-1592-1] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Accepted: 07/25/2014] [Indexed: 01/05/2023]
Abstract
Cells with "stemness" and tumor-initiating properties have been isolated from both hematological and solid tumors. These cells denominated as cancer stem cells (CSCs), representing rare populations within tumors, have the ability to metastasize and are resistant to standard therapies and immunotherapy. Heterogeneity and plasticity in the phenotype of CSCs have been described in relation to their tissue origin. Few definitive markers have been isolated for CSCs from human solid tumors, limiting their usage for in vivo identification of these cells. Nevertheless, progress in the emerging CSCs concept has been achieved gaining, at least for some type of tumors, their biological and immunological characterization. The recent identification of molecules and signaling pathways that are up-regulated or aberrantly induced in CSCs allowed the development of small agents for specifically targeting of CSCs. A general low immunogenic profile has been reported for CSCs with, in some cases, the identification of the mechanisms responsible of the impairment of cell-mediated immune responses. These concepts are discussed in the context of this review. Although CSCs still need to be fully characterized, potential candidate markers and/or signaling pathways, to be exploited for the design of novel CSC-targeting therapeutic strategies, are described in this review.
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Affiliation(s)
- Cristina Maccalli
- Unit of Immuno-biotherapy of Melanoma and Solid Tumors, San Raffaele Foundation Centre, Milan, Italy,
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15
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Londoño-Joshi AI, Arend RC, Aristizabal L, Lu W, Samant RS, Metge BJ, Hidalgo B, Grizzle WE, Conner M, Forero-Torres A, Lobuglio AF, Li Y, Buchsbaum DJ. Effect of niclosamide on basal-like breast cancers. Mol Cancer Ther 2014; 13:800-11. [PMID: 24552774 DOI: 10.1158/1535-7163.mct-13-0555] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Basal-like breast cancers (BLBC) are poorly differentiated and display aggressive clinical behavior. These tumors become resistant to cytotoxic agents, and tumor relapse has been attributed to the presence of cancer stem cells (CSC). One of the pathways involved in CSC regulation is the Wnt/β-catenin signaling pathway. LRP6, a Wnt ligand receptor, is one of the critical elements of this pathway and could potentially be an excellent therapeutic target. Niclosamide has been shown to inhibit the Wnt/β-catenin signaling pathway by causing degradation of LRP6. TRA-8, a monoclonal antibody specific to TRAIL death receptor 5, is cytotoxic to BLBC cell lines and their CSC-enriched populations. The goal of this study was to examine whether niclosamide is cytotoxic to BLBCs, specifically the CSC population, and if in combination with TRA-8 could produce increased cytotoxicity. Aldehyde dehydrogenase (ALDH) is a known marker of CSCs. By testing BLBC cells for ALDH expression by flow cytometry, we were able to isolate a nonadherent population of cells that have high ALDH expression. Niclosamide showed cytotoxicity against these nonadherent ALDH-expressing cells in addition to adherent cells from four BLBC cell lines: 2LMP, SUM159, HCC1187, and HCC1143. Niclosamide treatment produced reduced levels of LRP6 and β-catenin, which is a downstream Wnt/β-catenin signaling protein. The combination of TRA-8 and niclosamide produced additive cytotoxicity and a reduction in Wnt/β-catenin activity. Niclosamide in combination with TRA-8 suppressed growth of 2LMP orthotopic tumor xenografts. These results suggest that niclosamide or congeners of this agent may be useful for the treatment of BLBC.
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Affiliation(s)
- Angelina I Londoño-Joshi
- Authors' Affiliations: Departments of Pathology, Biology, Biostatistics, Medicine, and Radiation Oncology; Division of Gynecologic Oncology; Southern Research Institute; and Division of Hematology and Onocology, University of Alabama at Birmingham, Birmingham, Alabama
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16
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Lee SH, Kim MJ, Kim DW, Kang CD, Kim SH. Amurensin G enhances the susceptibility to tumor necrosis factor-related apoptosis-inducing ligand-mediated cytotoxicity of cancer stem-like cells of HCT-15 cells. Cancer Sci 2013; 104:1632-9. [PMID: 24118446 DOI: 10.1111/cas.12299] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Revised: 09/26/2013] [Accepted: 10/01/2013] [Indexed: 12/31/2022] Open
Abstract
Cancer stem cells (CSCs) are resistant to radiotherapy and chemotherapy and play a significant role in cancer recurrence. Design of better treatment strategies that can eliminate or otherwise control CSC populations in tumors is necessary. In this study, the sensitivity to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced cytotoxicity and the effect of amurensin G, a novel sirtuin 1 (SIRT1) inhibitor, were examined using the CSC-enriched fraction of HCT-15 human colon cancer cells. Cancer stem cell-enriched HCT-15 colony cells were paradoxically less sensitive to doxorubicin, and more sensitive to TRAIL-induced cytotoxicity, than their parental cells. Also, CD44(+) HCT-15 cells were more susceptible to TRAIL-mediated cytotoxicity than CD44(-) HCT-15 cells, possibly due to increased levels of death receptors DR4 and DR5 as well as c-Myc, and decreased levels of c-FLIPL /S in CD44(+) cells compared with CD44(-) HCT-15 cells. The combination effect of amurensin G on TRAIL-mediated cytotoxicity was much more apparent in CD44(+) cells than in CD44(-) HCT-15 cells, and this was associated with more prominent downregulation of c-FLIP(L/S) in CD44(+) cells than in CD44(-) HCT-15 cells. These results indicate that HCT-15 colony or CD44(+) cells, which may have CSC properties, are more sensitive to TRAIL than parental or CD44(-) HCT-15 cells. Amurensin G may be effective in eliminating colon CSCs and be applicable to potentiate the sensitivity of colon CSCs to TRAIL.
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Affiliation(s)
- Su-Hoon Lee
- Department of Biochemistry and Medical Research Institute, Pusan National University School of Medicine, Yangsan, Korea
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17
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Jazirehi AR, Arle D. Epigenetic regulation of the TRAIL/Apo2L apoptotic pathway by histone deacetylase inhibitors: an attractive approach to bypass melanoma immunotherapy resistance. AMERICAN JOURNAL OF CLINICAL AND EXPERIMENTAL IMMUNOLOGY 2013; 2:55-74. [PMID: 23885325 PMCID: PMC3714203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 12/26/2012] [Accepted: 01/19/2013] [Indexed: 06/02/2023]
Abstract
TNF-related apoptosis-inducing ligand (TRAIL/Apo2L) is a major cytotoxic mechanism employed by cytotoxic T lymphocytes (CTL) and natural killer (NK) cells to eradicate malignant cells. TRAIL/Apo2L interacts with its cognate receptors located on tumor cell surface namely, TRAIL-R1 (DR4), TRAIL-R2 (DR5), TRAIL-R3 (DcR1), TRAIL-R4 (DcR2) and osteoprotegerin (OPG). The exact function of DcR1 and DcR2 remains elusive. TRAIL/Apo2L or agonistic monoclonal antibodies directed against TRAIL/Apo2L death-inducing receptors (DR4, DR5) have become an attractive immunological therapeutic tools in clinical oncology due to their selective killing of tumors and lack of affinity towards healthy cells. Though a potent anti-cancer modality, some cancer cells exhibit inherent or acquired resistance to TRAIL/Apo2L. Postulated resistance mechanisms include up-regulation of c-FLIP, down-regulation of caspase-8, down-regulation/shedding of death receptors and an imbalanced ratio of pro- to anti-apoptotic genes due to aberrant activity of cellular survival signal transduction pathways. The development of resistance has spurred the use of combination therapy, in particular using small molecule sensitizing agents, to restore apoptosis sensitivity. A novel category of such compounds is histone deacetylase inhibitors (HDACi), which block HDACs from removing acetyl groups from histone tails thereby preventing silencing of pro-apoptotic genes and regulating the expression of non-histone proteins (i.e., apoptosis-associated genes), are effective agents in some malignancies. Some HDACi, such as Suberoylanilide Hydroxamic Acid (SAHA), have received FDA approval for cancer treatment. In various melanoma preclinical models, HDACi in conjunction with TRAIL/Apo2L, via modulation of apoptotic machinery, have proven to overcome acquired/inherent resistance to either agent. Here, we discuss recent findings on the role of TRAIL/Apo2L and its agonistic mAbs in melanoma immunotherapy with discussions on potential cellular and molecular events by which HDACi can sensitize metastatic melanoma to TRAIL/Apo2L-mediated immune-therapy, thereby, overcoming resistance.
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Affiliation(s)
- Ali R Jazirehi
- Department of Surgery, Division of Surgical Oncology, and the Jonsson Comprehensive Cancer Center, David Geffen School of Medicine at UCLA, University of California at Los Angeles Los Angeles, California 90095
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O'Toole SA, Beith JM, Millar EKA, West R, McLean A, Cazet A, Swarbrick A, Oakes SR. Therapeutic targets in triple negative breast cancer. J Clin Pathol 2013; 66:530-42. [DOI: 10.1136/jclinpath-2012-201361] [Citation(s) in RCA: 107] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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19
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Ferrari P, Nicolini A. Breast cancer stem cells: new therapeutic approaches. BREAST CANCER MANAGEMENT 2012. [DOI: 10.2217/bmt.12.43] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
SUMMARY Breast cancer stem cells are defined as a small subset of cells within a cancer that constitutes a reservoir of self-sustaining cells; they are low-dividing, have a reduced ability to undergo apoptosis and a higher ability of DNA repair, making them more resistant to conventional radiation and chemotherapy. The recent better understanding of the mechanisms of resistance to therapy related to stem cells has opened new scenarios and perspectives for therapeutic approaches. Some drugs active against breast cancer stem cells have been used in cancer therapy for years, other approaches are currently under clinical trials and many drugs are still in a preclinical phase. Only controlled clinical trials will answer the question whether or not these new therapeutical approaches alone or combined with the ongoing treatments significantly improve the outcome of breast cancer patients.
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Affiliation(s)
- Paola Ferrari
- Unit of Oncology 1, Department of Oncology, University of Pisa, Via Roma 67, 56126 Pisa, Italy
| | - Andrea Nicolini
- Unit of Oncology 2, Department of Oncology, University of Pisa, Via Roma 67, 56126 Pisa, Italy
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Breast cancer proteome takes more than two to tango on TRAIL: beat them at their own game. J Membr Biol 2012; 245:763-77. [PMID: 22899350 DOI: 10.1007/s00232-012-9490-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2012] [Accepted: 07/16/2012] [Indexed: 12/21/2022]
Abstract
Breast carcinogenesis is a multidimensional disease that has resisted drug-related solutions to date because of heterogeneity, disorganized spatiotemporal behavior of signal transduction cascades, cell cycle checkpoints, cell transition, plasticity, and impaired pro-apoptotic response. These synchronized oncogenic events, including protein-protein interaction, transcriptional-regulatory, and signaling networks, trigger genomic and transcriptional disturbances in TRAIL-mediated signaling network neighborhoods. Therefore, tumor cells often acquire the ability to escape death by suppressing cell death pathways that normally function to eliminate damaged and harmful cells. This review describes the TRAIL-mediated cell death signaling pathways, the interactions between these pathways, and the ways in which these pathways are deregulated in breast cancer.
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22
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Fulda S. Regulation of apoptosis pathways in cancer stem cells. Cancer Lett 2012; 338:168-73. [PMID: 22429999 DOI: 10.1016/j.canlet.2012.03.014] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2012] [Revised: 03/06/2012] [Accepted: 03/08/2012] [Indexed: 12/18/2022]
Abstract
Cancer stem cell are considered to represent a population within the bulk tumor that share many similarities to normal stem cells as far as their capacities to self-renew, differentiate, proliferate and to reconstitute the entire tumor upon serial transplantation are concerned. Since cancer stem cells have been shown to be critical for maintaining tumor growth and have been implicated in treatment resistance and tumor progression, they constitute relevant targets for therapeutic intervention. Indeed, it has been postulated that eradication of cancer stem cells will be pivotal in order to achieve long-term relapse-free survival. However, one of the hallmarks of cancer stem cells is their high resistance to undergo cell death including apoptosis in response to environmental cues or cytotoxic stimuli. Since activation of apoptosis programs in tumor cells underlies the antitumor activity of most currently used cancer therapeutics, it will be critical to develop strategies to overcome the intrinsic resistance to apoptosis of cancer stem cells. Thus, a better understanding of the molecular mechanisms that are responsible for the ability of cancer stem cells to evade apoptosis will likely open new avenues to target this critical pool of cells within the tumor in order to develop more efficient treatment options for patients suffering from cancer.
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Affiliation(s)
- Simone Fulda
- Institute for Experimental Cancer Research in Pediatrics, Goethe-University Frankfurt, Komturstr. 3a, 60528 Frankfurt, Germany.
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