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Attiyeh MA, Malhotra GK, Li D, Manoukian SB, Motarjem PM, Singh G. Defining MRI Superiority over CT for Colorectal and Neuroendocrine Liver Metastases. Cancers (Basel) 2023; 15:5109. [PMID: 37894475 PMCID: PMC10605771 DOI: 10.3390/cancers15205109] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 10/04/2023] [Accepted: 10/12/2023] [Indexed: 10/29/2023] Open
Abstract
BACKGROUND We compared CT and MRI for staging metastatic colorectal or neuroendocrine liver metastases (CRLMs and NELMs, respectively) to assess their impact on tumor burden. METHODS A prospectively maintained database was queried for patients who underwent both imaging modalities within 3 months, with two blinded radiologists (R1 and R2) independently assessing the images for liver lesions. To minimize recall bias, studies were grouped by modality, and were randomized and evaluated separately. RESULTS Our query yielded 76 patients (42 CRLMs; 34 NELMs) with low interrater variability (intraclass correlation coefficients: CT = 0.941, MRI = 0.975). For CRLMs, there were no significant differences in lesion number or size between CT and MRI. However, in NELMs, Eovist®-enhanced MRI detected more lesions (R1: 14.3 vs. 12.1, p = 0.02; R2: 14.4 vs. 12.4, p = 0.01) and smaller lesions (R1: 5.7 vs. 4.4, p = 0.03; R2: 4.8 vs. 2.9, p = 0.02) than CT. CONCLUSIONS CT and MRI are equivalent for CRLMs, but for NELMs, MRI outperforms CT in detecting more and smaller lesions, potentially influencing treatment planning and surgery.
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Affiliation(s)
- Marc A. Attiyeh
- Department of Surgical Oncology, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA;
| | - Gautam K. Malhotra
- Department of Surgery, USC, Keck School of Medicine, Los Angeles, CA 90033, USA
| | - Daneng Li
- Department of Medical Oncology, City of Hope National Medical Center, Duarte, CA 91010, USA
| | - Saro B. Manoukian
- Department of Radiology, City of Hope National Medical Center, Duarte, CA 91010, USA
| | - Pejman M. Motarjem
- Department of Radiology, City of Hope National Medical Center, Duarte, CA 91010, USA
| | - Gagandeep Singh
- Department of Surgery, City of Hope National Medical Center, Duarte, CA 91010, USA
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Bauman ZM, Yanala U, Waibel BH, Malhotra GK, Cemaj S, Evans CH, Schlitzkus LL. Sternal fixation for isolated traumatic sternal fractures improves pain and upper extremity range of motion. Eur J Trauma Emerg Surg 2021; 48:225-230. [PMID: 33388786 DOI: 10.1007/s00068-020-01568-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 12/02/2020] [Indexed: 10/22/2022]
Abstract
INTRODUCTION Sternal fractures are debilitating due to intractable pain, constant fracture movement and limited range of motion (ROM) of the upper extremities (UE). Traditional treatment comprises mainly of pain control, delaying return to daily activities. Recently, sternal fixation has gained popularity. There is, however, a lack of literature demonstrating efficacy. We report our experience of traumatically fractured sternal fixation. METHODS Following IRB approval, a retrospective chart review was completed for all patients undergoing sternal fixation by a single trauma surgeon at our Level I trauma center. Basic demographics were obtained. Primary outcomes included average cumulative pain scores, total cumulative narcotic amounts and total number of pain medication agents utilized prior to and after sternal fixation. Secondary outcome included physical therapy UE ROM before and after surgery. Paired t tests were used for comparison; significance set at p < 0.05. RESULTS Thirteen patients underwent sternal fixation from 8/2016 to 2/2018. Average age was 54.4 ± 20.8 years; 54% were female. All patients experienced blunt trauma; average injury severity score was 15.8 ± 10.9 and abbreviated chest injury score was 2.5 ± 0.51. Average intensive care unit/hospital length of stay was 2.3/10.2 days. Average pain scores significantly improved by a score of 3.5 postoperatively (preoperative = 7.08 ± 2.3, postoperative = 3.54 ± 2.5; p = 0.001). Total pain medications required by sternal fixation patients significantly decreased by 1 medication postoperatively (preoperative = 4.2 medications, postoperative = 3.2 medications; p = 0.002). Average narcotic requirements significantly decreased by 7.59 morphine milligram milliequivalents (MME) after sternal fixation (preoperative amount = 71.78 MME, postoperative amount = 64.19 MME; p = 0.041). Every patient had limited UE ROM preoperatively; however, all but one patient resumed full UE ROM postoperatively (p < 0.001). There were no postoperative complications. CONCLUSIONS Sternal fixation is a safe and effective procedure resulting in improved pain, decreased narcotic requirements, and faster recovery.
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Affiliation(s)
- Zachary M Bauman
- Division of Trauma, Emergency General Surgery and Critical Care Surgery, Department of Surgery, University of Nebraska Medical Center, 983280 Nebraska Medical Center, Omaha, NE, 68198-3280, USA.
| | - Ujwal Yanala
- Division of Trauma, Emergency General Surgery and Critical Care Surgery, Department of Surgery, University of Nebraska Medical Center, 983280 Nebraska Medical Center, Omaha, NE, 68198-3280, USA
| | - Brett H Waibel
- Division of Trauma, Emergency General Surgery and Critical Care Surgery, Department of Surgery, University of Nebraska Medical Center, 983280 Nebraska Medical Center, Omaha, NE, 68198-3280, USA
| | - Gautam K Malhotra
- Division of Trauma, Emergency General Surgery and Critical Care Surgery, Department of Surgery, University of Nebraska Medical Center, 983280 Nebraska Medical Center, Omaha, NE, 68198-3280, USA
| | - Samuel Cemaj
- Division of Trauma, Emergency General Surgery and Critical Care Surgery, Department of Surgery, University of Nebraska Medical Center, 983280 Nebraska Medical Center, Omaha, NE, 68198-3280, USA
| | - Charity H Evans
- Division of Trauma, Emergency General Surgery and Critical Care Surgery, Department of Surgery, University of Nebraska Medical Center, 983280 Nebraska Medical Center, Omaha, NE, 68198-3280, USA
| | - Lisa L Schlitzkus
- Division of Trauma, Emergency General Surgery and Critical Care Surgery, Department of Surgery, University of Nebraska Medical Center, 983280 Nebraska Medical Center, Omaha, NE, 68198-3280, USA
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Abstract
This article reviews the pathophysiology, risk factors, clinical presentation/diagnosis, and management of SCC.
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Affiliation(s)
- Rishi Batra
- Department of Surgery, University of Nebraska Medical Center, 983280 Nebraska Medical Center, Omaha, NE 68198, USA
| | - Gautam K Malhotra
- Department of Surgery, University of Nebraska Medical Center, 983280 Nebraska Medical Center, Omaha, NE 68198, USA
| | - Shailender Singh
- Internal Medicine, Division of Gastroenterology-Hepatology, 982000 Nebraska Medical Center, Omaha, NE 68198-2000, USA
| | - Chandrakanth Are
- Department of Surgery, University of Nebraska Medical Center, 986880 Nebraska Medical Center, Omaha, NE 68198-6880, USA.
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4
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Dhir M, Malhotra GK, Sohal DP, Hein NA, Smith LM, O’Reilly EM, Bahary N, Are C. Neoadjuvant treatment of pancreatic adenocarcinoma: a systematic review and meta-analysis of 5520 patients. World J Surg Oncol 2017; 15:183. [PMID: 29017581 PMCID: PMC5634869 DOI: 10.1186/s12957-017-1240-2] [Citation(s) in RCA: 91] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2017] [Accepted: 08/25/2017] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Recent years have seen standardization of the anatomic definitions of pancreatic adenocarcinoma, and increasing utilization of neoadjuvant therapy (NAT). The aim of the current review was to summarize the evidence for NAT in pancreatic adenocarcinoma since 2009, when consensus criteria for resectable (R), borderline resectable (BR), and locally advanced (LA) disease were endorsed. METHODS PubMed search was undertaken along with extensive backward search of the references of published articles to identify studies utilizing NAT for pancreatic adenocarcinoma. Abstracts from ASCO-GI 2014 and 2015 were also searched. RESULTS A total of 96 studies including 5520 patients were included in the final quantitative synthesis. Pooled estimates revealed 36% grade ≥ 3 toxicities, 5% biliary complications, 21% hospitalization rate and low mortality (0%, range 0-16%) during NAT. The majority of patients (59%) had stable disease. On an intention-to-treat basis, R0-resection rates varied from 63% among R patients to 23% among LA patients. R0 rates were > 80% among all patients who were resected after NAT. Among R and BR patients who underwent resection after NAT, median OS was 30 and 27.4 months, respectively. CONCLUSIONS The current study summarizes the recent literature for NAT in pancreatic adenocarcinoma and demonstrates improving outcomes after NAT compared to those historically associated with a surgery-first approach for pancreatic adenocarcinoma.
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Affiliation(s)
- Mashaal Dhir
- Department of Surgery, SUNY Upstate Medical University, Syracuse, NY 13210 USA
| | - Gautam K. Malhotra
- Department of Surgery, University of Nebraska Medical Center, Omaha, NE 98198 USA
| | - Davendra P.S. Sohal
- Division of Hematology and Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH 44195 USA
| | - Nicholas A. Hein
- Department of Biostatistics, College of Public Health, University of Nebraska Medical Center, Omaha, NE 68198 USA
| | - Lynette M. Smith
- Department of Biostatistics, College of Public Health, University of Nebraska Medical Center, Omaha, NE 68198 USA
| | - Eileen M. O’Reilly
- David M. Rubenstein Center for Pancreatic Cancer, Memorial Sloan Kettering Cancer Center, New York, NY 10065 USA
| | - Nathan Bahary
- Department of Medicine, Division of Hematology and Oncology, University of Pittsburgh Medical Center, Pittsburgh, PA 15232 USA
| | - Chandrakanth Are
- Department of Surgery, Division of Surgical Oncology, University of Nebraska Medical Center, Omaha, NE 98198 USA
- Department of Surgery/Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, NE 68198 USA
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Malhotra GK, Yanala U, Ravipati A, Follet M, Vijayakumar M, Are C. Global trends in esophageal cancer. J Surg Oncol 2017; 115:564-579. [PMID: 28320055 DOI: 10.1002/jso.24592] [Citation(s) in RCA: 201] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2017] [Accepted: 02/02/2017] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND OBJECTIVES Esophageal Cancer (EC) is a lethal malignancy with poor prognosis and significant variations in the incidence, mortality, and histopathology based on geographic regions. The aim of this study was to quantitatively analyze these variations to identify patterns and areas for further research. METHODS We utilized the GLOBOCAN 2012, and Cancer Incidence in five Continents, Volume X (CI5X) database to analyze variations in EC incidence and mortality. RESULTS We found the EC incidence and mortality is geographically varied with a particularly high burden in East Asia and Eastern/Southern Africa where esophageal squamous cell carcinoma (SCC) predominates over adenocarcinoma (AC). Interestingly, there is a dichotomy between the high incidence of esophageal SCC in East Africa and low incidence in West Africa. The global incidence and mortality from EC is expected to rise in the coming decades. Asia, and China in particular, will continue to be the areas most burdened by EC, while Africa is expected to surpass the incidence and mortality rates of Europe. CONCLUSIONS The global burden of EC is expected to rise in the coming years. Understanding the geographic, environmental, and genetic contributors to the development of EC will be essential in combating its prevalence.
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Affiliation(s)
- Gautam K Malhotra
- Department of Surgery, University of Nebraska Medical Center, Omaha, Nebraska
| | - Ujwal Yanala
- Department of Surgery, University of Nebraska Medical Center, Omaha, Nebraska
| | | | - Matthew Follet
- Department of Surgery, University of Nebraska Medical Center, Omaha, Nebraska
| | | | - Chandrakanth Are
- Department of Surgery, University of Nebraska Medical Center, Omaha, Nebraska
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Davalos AR, Kawahara M, Malhotra GK, Schaum N, Huang J, Ved U, Beausejour CM, Coppe JP, Rodier F, Campisi J. p53-dependent release of Alarmin HMGB1 is a central mediator of senescent phenotypes. J Exp Med 2013. [DOI: 10.1084/jem2106oia3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Davalos AR, Kawahara M, Malhotra GK, Schaum N, Huang J, Ved U, Beausejour CM, Coppe JP, Rodier F, Campisi J. p53-dependent release of Alarmin HMGB1 is a central mediator of senescent phenotypes. ACTA ACUST UNITED AC 2013; 201:613-29. [PMID: 23649808 PMCID: PMC3653366 DOI: 10.1083/jcb.201206006] [Citation(s) in RCA: 312] [Impact Index Per Article: 28.4] [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] [Indexed: 12/14/2022]
Abstract
Cellular senescence irreversibly arrests proliferation in response to potentially oncogenic stress. Senescent cells also secrete inflammatory cytokines such as IL-6, which promote age-associated inflammation and pathology. HMGB1 (high mobility group box 1) modulates gene expression in the nucleus, but certain immune cells secrete HMGB1 as an extracellular Alarmin to signal tissue damage. We show that nuclear HMGB1 relocalized to the extracellular milieu in senescent human and mouse cells in culture and in vivo. In contrast to cytokine secretion, HMGB1 redistribution required the p53 tumor suppressor, but not its activator ATM. Moreover, altered HMGB1 expression induced a p53-dependent senescent growth arrest. Senescent fibroblasts secreted oxidized HMGB1, which stimulated cytokine secretion through TLR-4 signaling. HMGB1 depletion, HMGB1 blocking antibody, or TLR-4 inhibition attenuated senescence-associated IL-6 secretion, and exogenous HMGB1 stimulated NF-κB activity and restored IL-6 secretion to HMGB1-depleted cells. Our findings identify senescence as a novel biological setting in which HMGB1 functions and link HMGB1 redistribution to p53 activity and senescence-associated inflammation.
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Affiliation(s)
- Albert R Davalos
- Lawrence Berkeley National Laboratory, Life Sciences Division, Berkeley, CA 94720, USA
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Malhotra GK, Kobayashi R, Poole JA. Absence of mannose-binding lectin in a female with relapsing-remitting multiple sclerosis. Isr Med Assoc J 2012; 14:333-334. [PMID: 22799071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Affiliation(s)
- Gautam K Malhotra
- Pulmonary, Critical Care, Sleep and Allergy Division, Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68198-5300, USA
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9
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Zhao X, Malhotra GK, Band H, Band V. Derivation of myoepithelial progenitor cells from bipotent mammary stem/progenitor cells. PLoS One 2012; 7:e35338. [PMID: 22514728 PMCID: PMC3325967 DOI: 10.1371/journal.pone.0035338] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Accepted: 03/15/2012] [Indexed: 11/19/2022] Open
Abstract
There is increasing evidence that breast and other cancers originate from and are maintained by a small fraction of stem/progenitor cells with self-renewal properties. Recent molecular profiling has identified six major subtypes of breast cancer: basal-like, ErbB2-overexpressing, normal breast epithelial-like, luminal A and B, and claudin-low subtypes. To help understand the relationship among mammary stem/progenitor cells and breast cancer subtypes, we have recently derived distinct hTERT-immortalized human mammary stem/progenitor cell lines: a K5(+)/K19(-) type, and a K5(+)/K19(+) type. Under specific culture conditions, bipotent K5(+)/K19(-) stem/progenitor cells differentiated into stable clonal populations that were K5(-)/K19(-) and exhibit self-renewal and unipotent myoepithelial differentiation potential in contrast to the parental K5(+)/K19(-) cells which are bipotent. These K5(-)/K19(-) cells function as myoepithelial progenitor cells and constitutively express markers of an epithelial to mesenchymal transition (EMT) and show high invasive and migratory abilities. In addition, these cells express a microarray signature of claudin-low breast cancers. The EMT characteristics of an un-transformed unipotent mammary myoepithelial progenitor cells together with claudin-low signature suggests that the claudin-low breast cancer subtype may arise from myoepithelial lineage committed progenitors. Availability of immortal MPCs should allow a more definitive analysis of their potential to give rise to claudin-low breast cancer subtype and facilitate biological and molecular/biochemical studies of this disease.
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Affiliation(s)
- Xiangshan Zhao
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - Gautam K. Malhotra
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - Hamid Band
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
- Department of Microbiology and Pathology, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
- Department of Pharmacology and Experimental Neuroscience, College of Medicine, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
- The Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - Vimla Band
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
- The Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
- * E-mail:
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Abstract
Recent advances in our understanding of breast cancer biology have led to the identification of a subpopulation of cells within tumors that appear to be responsible for initiating and propagating the cancer. These tumor initiating cells are not only unique in their ability to generate tumors, but also share many similarities with elements of normal adult tissue stem cells, and have therefore been termed cancer stem cells (CSCs). These CSCs often inappropriately use many of the same signaling pathways utilized by their normal stem cell counterparts which may present a challenge to the development of CSC specific therapies. Here, we discuss three major stem cell signaling pathways (Notch, Wnt, and Hedgehog); with a focus on their function in normal mammary gland development and their misuse in breast cancer stem cell fate determination.
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Affiliation(s)
- Gautam K Malhotra
- Department of Genetics, Cell Biology and Anatomy, College of Medicine, University of Nebraska Medical Center, Nebraska Medical Center, Omaha, NE, USA
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11
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Zhao X, Malhotra GK, Band H, Band V. A block in lineage differentiation of immortal human mammary stem / progenitor cells by ectopically-expressed oncogenes. J Carcinog 2011; 10:39. [PMID: 22279424 PMCID: PMC3263028 DOI: 10.4103/1477-3163.91415] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2011] [Accepted: 10/20/2011] [Indexed: 01/19/2023] Open
Abstract
INTRODUCTION Emerging evidence suggests a direct role of cancer stem cells (CSCs) in the development of breast cancer. In vitro cellular models that recapitulate properties of CSCs are therefore highly desirable. We have previously shown that normal human mammary epithelial cells (hMECs) immortalized with human telomerase reverse transcriptase (hTERT) possess properties of mammary stem / progenitor cells. MATERIALS AND METHODS In the present study, we used this cell system to test the idea that other known hMEC-immortalizing oncogenes (RhoA, HPVE6, HPVE7, p53 mutant, and treatment with γ-radiation), share with hTERT, the ability to maintain mammary stem / progenitor cells. RESULTS The results presented here demonstrate that similar to hMECs immortalized with hTERT, all hMEC cell lines immortalized using various oncogenic strategies express stem / progenitor cell markers. Furthermore, analyses using 2D and 3D culture assays demonstrate that all the immortal cell lines retain their ability to self-renew and to differentiate along the luminal lineage. Remarkably, the stem / progenitor cell lines generated using various oncogenic strategies exhibit a block in differentiation along the myoepithelial lineage, a trait that is retained on hTERT-immortalized stem / progenitors. The inability to differentiate along the myoepithelial lineage could be induced by ectopic mutant p53 expression in hTERT-immortalized hMEC. CONCLUSIONS Our studies demonstrate that stem / progenitor cell characteristics of hMECs are maintained upon immortalization by using various cancer-relevant oncogenic strategies. Oncogene-immortalized hMECs show a block in their ability to differentiate along the myoepithelial lineage. Abrogation of the myoepithelial differentiation potential by a number of distinct oncogenic insults suggests a potential explanation for the predominance of luminal and rarity of myoepithelial breast cancers.
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Affiliation(s)
- Xiangshan Zhao
- Department of Genetics, Cell Biology and Anatomy, College of Medicine, University of Nebraska Medical Center, Nebraska Medical Center, Omaha, NE, USA
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12
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Davalos AR, Kawahara M, Malhotra GK, Huang J, Ved U, Rodier F, Beausejour C, Coppe JP, Campisi J. Abstract A3: p53-dependent release of alarmin HMGB1 is a central mediator of senescent phenotypes. Cancer Res 2011. [DOI: 10.1158/1538-7445.fbcr11-a3] [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
Cellular senescence irreversibly arrests the proliferation of cells at risk for malignant transformation in part through activities of the transcriptional regulator and tumor suppressor p53. Cells that senesce owing to DNA damage also secrete many biologically active factors, including inflammatory cytokines such as IL-6. Some data suggest that the senescence associated secretory phenotype (SASP) creates a tumor permissive environment. However, we find that senescent cells secrete a potent bioactive molecule—High Mobility Group Box 1 (HMGB1) protein, which is unusual in having two distinct functions. Intracellularly, it binds chromatin and modulates transcription, including stimulating p53 activity. In addition, necrosis or microbial infection causes HMGB1 leakage or active secretion, respectively, whereupon it functions as an extracellular alarmin to signal tissue damage and promote tissue regeneration, stem cell recruitment and immune activation. We show that HMGB1 is largely nuclear in non-senescent human and mouse fibroblasts and epithelial cells, but is actively exported from the nucleus and secreted by senescent cells. In culture and in vivo, HMGB1 re-localization occurred prior to the appearance of other hallmarks of senescence, and depended on the function of p53, but not the upstream p53 activator ATM, which distinguished HMGB1 secretion from the SASP. Aged mice or human sera contained significantly higher levels of circulating HMGB1 compared to sera from young mice or human subjects. Disruption of HMGB1 stoichiometry, either by overexpression or depletion, induced a p53-dependent senescence growth arrest, but only HMGB1 overexpression, not HMGB1 depletion, promoted IL-6 secretion. Senescence-associated secretion required endogenous and secreted HMGB1 because deletion of endogenous HMGB1— or addition of an HMGB1 blocking antibody – attenuated IL-6 secretion. Recombinant HMGB1 protein induced IL-6 secretion in cells depleted, but not harboring, endogenous HMGB1. Depletion of endogenous HMGB1 promoted NF-κ B transcriptional activity in cells cultured with recombinant HMGB1. Our findings identify a novel biological setting (senescence), independent of necrosis or microbial infection, in which HMGB1 secretion occurs in vitro and in vivo, and link senescence-dependent HMGB1 redistribution to p53 activity and inflammatory cytokine secretion.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the Second AACR International Conference on Frontiers in Basic Cancer Research; 2011 Sep 14-18; San Francisco, CA. Philadelphia (PA): AACR; Cancer Res 2011;71(18 Suppl):Abstract nr A3.
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Affiliation(s)
| | | | | | - Jiahao Huang
- 4Cold Spring Harbor Laboratory, Cold Spring Harbor, NY
| | - Urvi Ved
- 2Lawrence Berkeley National Laboratory, Berkeley, CA
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Abstract
Increased understanding of the molecular heterogeneity that is intrinsic to the various subtypes of breast cancer will likely shape the future of breast cancer diagnosis, prognosis, and treatment. Advances in the field over the last several decades have been remarkable and have clearly translated into better patient care as evidenced by the earlier detection, better prognosis, and new targeted therapies. There have been two recent advances in the breast cancer research field that have lead to paradigm shifts: first, the identification of intrinsic breast tumor subtypes, which has changed the way we think about breast cancer and second, the recent characterization of cancer stem cells (CSCs), which are suspected to be responsible for tumor initiation, recurrence and resistance to therapy, have opened new exciting avenues to think about breast cancer therapeutic strategies. While these advances constitute major paradigm shifts within the research realm, the clinical arena has yet to adopt and apply our understanding of the molecular basis of the disease to early diagnosis, prognosis and therapy of breast cancers. Here, we will review the current clinical approach to classification of breast cancers, newer molecular-based classification schemes, and potential future of biomarkers representing a functional classification of breast cancer.
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Affiliation(s)
- Gautam K Malhotra
- Department of Genetics, University of Nebraska Medical Center, Omaha, USA
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