234 results on '"Astsaturov, Igor"'
Search Results
202. The Relevance of Cytological Studies and Ki-67 Reactivity to the Clinical Course of Chronic Lymphocytic Leukemia
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Astsaturov, Igor A., primary, Samoilova, Rimma S., additional, Iakhnina, Elena I., additional, Pivnik, Alexander V., additional, and Vorobiov, Andrei I., additional
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- 1997
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203. Aurora A kinase (AURKA) in normal and pathological cell division.
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Nikonova, Anna, Astsaturov, Igor, Serebriiskii, Ilya, Dunbrack, Roland, and Golemis, Erica
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KINASES , *CELL division , *PATHOLOGY , *SPATIO-temporal variation , *GENE amplification , *CLINICAL trials - Abstract
Temporally and spatially controlled activation of the Aurora A kinase (AURKA) regulates centrosome maturation, entry into mitosis, formation and function of the bipolar spindle, and cytokinesis. Genetic amplification and mRNA and protein overexpression of Aurora A are common in many types of solid tumor, and associated with aneuploidy, supernumerary centrosomes, defective mitotic spindles, and resistance to apoptosis. These properties have led Aurora A to be considered a high-value target for development of cancer therapeutics, with multiple agents currently in early-phase clinical trials. More recently, identification of additional, non-mitotic functions and means of activation of Aurora A during interphase neurite elongation and ciliary resorption have significantly expanded our understanding of its function, and may offer insights into the clinical performance of Aurora A inhibitors. Here we review the mitotic and non-mitotic functions of Aurora A, discuss Aurora A regulation in the context of protein structural information, and evaluate progress in understanding and inhibiting Aurora A in cancer. [ABSTRACT FROM AUTHOR]
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- 2013
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204. Effective antibody therapy induces host-protective antitumor immunity that is augmented by TLR4 agonist treatment.
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Wang, Shangzi, Astsaturov, Igor, Bingham, Catherine, McCarthy, Kenneth, Mehren, Margaret, Xu, Wei, Alpaugh, R., Tang, Yong, Littlefield, Bruce, Hawkins, Lynn, Ishizaka, Sally, and Weiner, Louis
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CANCER immunotherapy , *CANCER chemotherapy , *TRASTUZUMAB , *ANTINEOPLASTIC antibiotics , *TREATMENT effectiveness , *CELLULAR immunity , *TRANSGENIC mice - Abstract
Toll-like receptors are potent activators of the innate immune system and generate signals leading to the initiation of the adaptive immune response that can be utilized for therapeutic purposes. We tested the hypothesis that combined treatment with a Toll-like receptor agonist and an antitumor monoclonal antibody is effective and induces host-protective antitumor immunity. C57BL/6 human mutated HER2 (hmHER2) transgenic mice that constitutively express kinase-deficient human HER2 under control of the CMV promoter were established. These mice demonstrate immunological tolerance to D5-HER2, a syngeneic human HER2-expressing melanoma cell line. This human HER2-tolerant model offers the potential to serve as a preclinical model to test both antibody therapy and the immunization potential of human HER2-targeted therapeutics. Here, we show that E6020, a Toll-like receptor-4 (TLR4) agonist effectively boosted the antitumor efficacy of the monoclonal antibody trastuzumab in immunodeficient C57BL/6 SCID mice as well as in C57BL/6 hmHER2 transgenic mice. E6020 and trastuzumab co-treatment resulted in significantly greater inhibition of tumor growth than was observed with either agent individually. Furthermore, mice treated with the combination of trastuzumab and the TLR4 agonist were protected against rechallenge with human HER2-transfected tumor cells in hmHER2 transgenic mouse strains. These findings suggest that combined treatment with trastuzumab and a TLR4 agonist not only promotes direct antitumor effects but also induces a host-protective human HER2-directed adaptive immune response, indicative of a memory response. These data provide an immunological rationale for testing TLR4 agonists in combination with antibody therapy in patients with cancer. [ABSTRACT FROM AUTHOR]
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- 2012
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205. Significance of Pathologic Response to Preoperative Therapy in Pancreatic Cancer.
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Chun, Yun, Cooper, Harry, Cohen, Steven, Konski, Andre, Burtness, Barbara, Denlinger, Crystal, Astsaturov, Igor, Hall, Michael, and Hoffman, John
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Background: Pathologic response to preoperative therapy is increasingly recognized as an important prognostic factor in solid tumors. The impact of pathologic response on survival in pancreatic adenocarcinoma is not well established. Methods: Data on 135 consecutive patients treated with chemoradiation followed by pancreatectomy for adenocarcinoma of the pancreatic head and/or body between July 1987 and May 2009 were reviewed. Histopathologic examination was performed in 107 patients to determine pathologic response, defined as minor (<50% fibrosis relative to residual neoplastic cells), partial (50-94% fibrosis), or major (95-100% fibrosis). Results: Minor, partial, and major pathologic response rates were 17% ( n = 18), 64% ( n = 68), and 19% ( n = 21), including a 7% ( n = 8) complete pathologic response rate. Pathologic response correlated with R0 resection ( P = 0.019), negative lymph nodes ( P = 0.006), and smaller tumor size ( P = 0.001). Median survival rates by pathologic response were as follows: 17 months [95% confidence interval (CI), 0-36 months] for minor response, 20 months (95% CI, 17-23 months) for partial response, and 66 months (95% CI, 8-124 months) for major response (minor versus partial response, P = not significant; partial versus major response, P < 0.001). On multivariate analysis, major pathologic response was the only factor significantly associated with improved survival ( P = 0.025; hazard ratio, 2.26). Conclusions: Major pathologic response to preoperative therapy occurs in a minority of patients with pancreatic adenocarcinoma and is independently associated with prolonged survival. [ABSTRACT FROM AUTHOR]
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- 2011
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206. Defining Venous Involvement in Borderline Resectable Pancreatic Cancer.
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Chun, Yun, Milestone, Barton, Watson, James, Cohen, Steven, Burtness, Barbara, Engstrom, Paul, Haluszka, Oleh, Tokar, Jeffrey, Hall, Michael, Denlinger, Crystal, Astsaturov, Igor, and Hoffman, John
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Background: Pancreatic adenocarcinoma impinging the portal and/or superior mesenteric vein (PV-SMV) is classified as borderline resectable, and preoperative chemoradiation is recommended to increase the margin-negative resection rate. There is no consensus about what degree of venous impingement constitutes borderline resectability. Methods: All patients undergoing potentially curative pancreatectomy for pancreatic adenocarcinoma were reviewed. Venous involvement was classified by preoperative computed tomography according to Ishikawa types: (I) normal, (II) smooth shift without narrowing, (III) unilateral narrowing, (IV) bilateral narrowing, (V) bilateral narrowing with collateral veins. Results: From 1990-2009, 109 patients underwent resection of pancreatic adenocarcinoma involving the PV-SMV. Seventy-four patients received preoperative chemoradiation, whereas 35 did not. Patients who received preoperative therapy had a significantly longer median overall survival rate of 23 months compared with 15 months for patients without preoperative therapy ( P = 0.001). Preoperative chemoradiation was associated with higher R0 resection rate and negative lymph nodes (both P < 0.0001) but did not affect the need for vein resection. When stratified by Ishikawa types, preoperative therapy was associated with improved overall survival among patients with types II and III but not types IV and V. Similarly, the correlation between preoperative therapy and R0 resection rate was observed only among patients with Ishikawa types II and III. Conclusions: Preoperative therapy for borderline resectable pancreatic adenocarcinoma is associated with higher margin-negative resection and survival rates in patients with Ishikawa type II and III tumors, defined as a smooth shift or unilateral narrowing of the PV-SMV. Patients with bilateral venous narrowing were less likely to benefit from preoperative treatment. [ABSTRACT FROM AUTHOR]
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- 2010
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207. Identification of New Regulators of Pancreatic Cancer Cell Sensitivity to Oxaliplatin and Cisplatin.
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Skripova, Vera, Vlasenkova, Ramilia, Zhou, Yan, Astsaturov, Igor, and Kiyamova, Ramziya
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PANCREATIC cancer ,CISPLATIN ,CANCER cells ,OXALIPLATIN ,SINGLE-stranded DNA ,NADH dehydrogenase ,NUCLEAR proteins - Abstract
The chemoresistance of tumor cells is one of the most urgent challenges in modern oncology and in pancreatic cancer, in which this problem is the most prominent. Therefore, the identification of new chemosensitizing co-targets may be a path toward increasing chemotherapy efficacy. In this work, we performed high-performance in vitro knockout CRISPR/Cas9 screening to find potential regulators of the sensitivity of pancreatic cancer. For this purpose, MIA PaCa-2 cells transduced with two sgRNA libraries ("cell cycle/nuclear proteins genes" and "genome-wide") were screened by oxaliplatin and cisplatin. In total, 173 candidate genes were identified as potential regulators of pancreatic cancer cell sensitivity to oxaliplatin and/or cisplatin; among these, 25 genes have previously been reported, while 148 genes were identified for the first time as potential platinum drug sensitivity regulators. We found seven candidate genes involved in pancreatic cancer cell sensitivity to both cisplatin and oxaliplatin. Gene ontology enrichment analysis reveals the enrichment of single-stranded DNA binding, damaged DNA binding pathways, and four associated with NADH dehydrogenase activity. Further investigation and validation of the obtained results by in vitro, in vivo, and bioinformatics approaches, as well as literature analysis, will help to identify novel pancreatic cancer platinum sensitivity regulators. [ABSTRACT FROM AUTHOR]
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- 2022
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208. Evaluating the impact of age on immune checkpoint therapy biomarkers.
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Erbe, Rossin, Wang, Zheyu, Wu, Sharon, Xiu, Joanne, Zaidi, Neeha, La, Jennifer, Tuck, David, Fillmore, Nathanael, Giraldo, Nicolas A., Topper, Michael, Baylin, Stephen, Lippman, Marc, Isaacs, Claudine, Basho, Reva, Serebriiskii, Ilya, Lenz, Heinz-Josef, Astsaturov, Igor, Marshall, John, Taverna, Josephine, and Lee, Jerry
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- 2021
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209. Overview of Monoclonal Antibodies and Small Molecules Targeting the Epidermal Growth Factor Receptor Pathway in Colorectal Cancer
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Snyder, Lorraine C., Astsaturov, Igor, and Weiner, Louis M.
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The epidermal growth factor receptor (EGFR) provides survival signals and is overexpressed in the majority of colorectal cancers. As more is learned about the molecular details of EGFR signaling, antibodies can be designed to interfere with specific domains of the EGFR molecule. In this review, we analyze preclinical and current clinical data on EGFR-targeting molecules and their potential role in the treatment of colorectal cancer. Cetuximab binds to domain III of EGFR and hinders ligand binding. It is now approved by the US Food and Drug Administration for metastatic colorectal cancer treatment. Panitumumab is another widely studied anti-EGFR antibody with similar properties. Bispecific antibodies are modified immunoglobulin molecules containing 2 different binding specificities. These antibodies can redirect the immune response against tumor cells by tethering effector cells such as CD3μ-expressing T cells or CD16-expressing natural killer cells and granulocytes to the surface of cancer cells. Tyrosine kinase inhibitors are quinazoline-derived, low molecular weight synthetic molecules that can block the intracellular tyrosine kinase domain of several receptors, including EGFR, Erb2, and vascular endothelial growth factor receptor, and thereby inhibit ligand-induced receptor phosphorylation and abrogate the biologic effect of EGFR signaling. The presence of skin rash and EGFRgene amplification have been advanced as possible predictors of clinical effectiveness of targeted anti-EGFR therapies.
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- 2006
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210. Preparation of mouse pancreatic tumor for single-cell RNA sequencing and analysis of the data.
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Surumbayeva, Aizhan, Kotliar, Michael, Gabitova-Cornell, Linara, Kartashov, Andrey, Peri, Suraj, Salomonis, Nathan, Barski, Artem, and Astsaturov, Igor
- Abstract
Preparation of single-cell suspension from primary tumor tissue can provide a valuable resource for functional, genetic, proteomic, and tumor microenvironment studies. Here, we describe an effective protocol for mouse pancreatic tumors dissociation with further processing of tumor suspension for single-cell RNA sequencing analysis of cellular populations. We further provide an outline of the bioinformatics processing of the data and clustering of heterogeneous cellular populations comprising pancreatic tumors using Common Workflow Language (CWL) pipelines within user-friendly Scientific Data Analysis Platform (https://SciDAP.com).
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- 2021
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211. A framework for advancing our understanding of cancer-associated fibroblasts
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Sahai, Erik, Astsaturov, Igor, Cukierman, Edna, DeNardo, David G, Egeblad, Mikala, Evans, Ronald M, Fearon, Douglas, Greten, Florian R, Hingorani, Sunil R, Hunter, Tony, Hynes, Richard O, Jain, Rakesh K, Janowitz, Tobias, Jorgensen, Claus, Kimmelman, Alec C, Kolonin, Mikhail G, Maki, Robert G, R Scott Powers, Puré, Ellen, Ramirez, Daniel C, Scherz-Shouval, Ruth, Sherman, Mara H, Stewart, Sheila, Tlsty, Thea D, Tuveson, David A, Watt, Fiona M, Weaver, Valerie, Ashani T Weeraratna, and Werb, Zena
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Model organisms ,Cell Biology ,Tumour Biology ,3. Good health ,Imaging - Abstract
Cancer-associated fibroblasts (CAFs) are a key component of the tumour microenvironment with diverse functions, including matrix deposition and remodelling, extensive reciprocal signalling interactions with cancer cells and crosstalk with infiltrating leukocytes. As such, they are a potential target for optimizing therapeutic strategies against cancer. However, many challenges are present in ongoing attempts to modulate CAFs for therapeutic benefit. These include limitations in our understanding of the origin of CAFs and heterogeneity in CAF function, with it being desirable to retain some antitumorigenic functions. On the basis of a meeting of experts in the field of CAF biology, we summarize in this Consensus Statement our current knowledge and present a framework for advancing our understanding of this critical cell type within the tumour microenvironment.
212. A framework for advancing our understanding of cancer-associated fibroblasts
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Sahai, Erik, Astsaturov, Igor, Cukierman, Edna, DeNardo, David G, Egeblad, Mikala, Evans, Ronald M, Fearon, Douglas, Greten, Florian R, Hingorani, Sunil R, Hunter, Tony, Hynes, Richard O, Jain, Rakesh K, Janowitz, Tobias, Jorgensen, Claus, Kimmelman, Alec C, Kolonin, Mikhail G, Maki, Robert G, R Scott Powers, Puré, Ellen, Ramirez, Daniel C, Scherz-Shouval, Ruth, Sherman, Mara H, Stewart, Sheila, Tlsty, Thea D, Tuveson, David A, Watt, Fiona M, Weaver, Valerie, Ashani T Weeraratna, and Werb, Zena
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Model organisms ,Cell Biology ,Tumour Biology ,3. Good health ,Imaging - Abstract
Cancer-associated fibroblasts (CAFs) are a key component of the tumour microenvironment with diverse functions, including matrix deposition and remodelling, extensive reciprocal signalling interactions with cancer cells and crosstalk with infiltrating leukocytes. As such, they are a potential target for optimizing therapeutic strategies against cancer. However, many challenges are present in ongoing attempts to modulate CAFs for therapeutic benefit. These include limitations in our understanding of the origin of CAFs and heterogeneity in CAF function, with it being desirable to retain some antitumorigenic functions. On the basis of a meeting of experts in the field of CAF biology, we summarize in this Consensus Statement our current knowledge and present a framework for advancing our understanding of this critical cell type within the tumour microenvironment.
213. Suppression of Ca2+ signaling enhances melanoma progression.
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Gross, Scott, Hooper, Robert, Tomar, Dhanendra, Armstead, Alexander P, Shanas, No'ad, Mallu, Pranava, Joshi, Hinal, Ray, Suravi, Chong, Parkson Lee‐Gau, Astsaturov, Igor, Farma, Jeffrey M, Cai, Kathy Q, Chitrala, Kumaraswamy Naidu, Elrod, John W, Zaidi, M Raza, and Soboloff, Jonathan
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MELANOMA , *GLUCOSE metabolism , *ANTICHOLESTEREMIC agents , *CANCER invasiveness , *FUNCTIONAL analysis - Abstract
The role of store‐operated Ca2+ entry (SOCE) in melanoma metastasis is highly controversial. To address this, we here examined UV‐dependent metastasis, revealing a critical role for SOCE suppression in melanoma progression. UV‐induced cholesterol biosynthesis was critical for UV‐induced SOCE suppression and subsequent metastasis, although SOCE suppression alone was both necessary and sufficient for metastasis to occur. Further, SOCE suppression was responsible for UV‐dependent differences in gene expression associated with both increased invasion and reduced glucose metabolism. Functional analyses further established that increased glucose uptake leads to a metabolic shift towards biosynthetic pathways critical for melanoma metastasis. Finally, examination of fresh surgically isolated human melanoma explants revealed cholesterol biosynthesis‐dependent reduced SOCE. Invasiveness could be reversed with either cholesterol biosynthesis inhibitors or pharmacological SOCE potentiation. Collectively, we provide evidence that, contrary to current thinking, Ca2+ signals can block invasive behavior, and suppression of these signals promotes invasion and metastasis. Synopsis: The role of STIM/Orai‐mediated store‐operated Ca2+ entry (SOCE) in melanoma is debated. This work reports a novel signaling axis linking UV exposure to cholesterol biosynthesis and suppression of SOCE, promoting aberrant cancer metabolism and invasive phenotypes.UV radiation suppresses SOCE and enhances invasiveness of melanoma cell lines in vivo.STIM‐Orai inhibition is sufficient to drive metastasis in syngeneic mice.Increased cholesterol biosynthesis is required for UV‐induced SOCE suppression and melanoma metastasis.UV‐induced SOCE reduction enhances glucose uptake and anabolic O‐GlcNAcylation, shifting melanoma cells to a more invasive phenotype.Cholesterol‐mediated SOCE suppression and increased O‐GlcNAcylation are conserved in melanoma patient explants. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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214. Regulation of cholesterol biosynthesis and cancer signaling
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Gorin, Andrey, Gabitova, Linara, and Astsaturov, Igor
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CHOLESTEROL , *BIOSYNTHESIS , *LIPIDS , *STEROLS , *CELLULAR signal transduction , *MOLECULAR oncology - Abstract
Cellular growth is highly dependent on sustained production of lipids. Sterol composition of cellular membranes determines multiple biochemical and biophysical properties of membrane-based processes including vesicle traffic, receptor signaling, and assembly of protein complexes. Lipid biogenesis has become an attractive biochemical target in cancer given the high level of dependency on sterols and lipids in a cancer cell. This review summarized the current knowledge of mechanisms of interaction between the metabolism of sterols and receptor signaling. [Copyright &y& Elsevier]
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- 2012
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215. Platelet microRNAs inhibit primary tumor growth via broad modulation of tumor cell mRNA expression in ectopic pancreatic cancer in mice.
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Wurtzel, Jeremy G. T., Lazar, Sophia, Sikder, Sonali, Cai, Kathy Q., Astsaturov, Igor, Weyrich, Andrew S., Rowley, Jesse W., and Goldfinger, Lawrence E.
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TUMOR growth , *GENE expression , *PANCREATIC cancer , *BLOOD platelets , *GENETIC regulation - Abstract
We investigated the contributions of platelet microRNAs (miRNAs) to the rate of growth and regulation of gene expression in primary ectopic tumors using mouse models. We previously identified an inhibitory role for platelets in solid tumor growth, mediated by tumor infiltration of platelet microvesicles (microparticles) which are enriched in platelet-derived miRNAs. To investigate the specific roles of platelet miRNAs in tumor growth models, we implanted pancreatic ductal adenocarcinoma cells as a bolus into mice with megakaryocyte-/platelet-specific depletion of mature miRNAs. We observed an ~50% increase in the rate of growth of ectopic primary tumors in these mice compared to controls including at early stages, associated with reduced apoptosis in the tumors, in particular in tumor cells associated with platelet microvesicles—which were depleted of platelet-enriched miRNAs—demonstrating a specific role for platelet miRNAs in modulation of primary tumor growth. Differential expression RNA sequencing of tumor cells isolated from advanced primary tumors revealed a broad cohort of mRNAs modulated in the tumor cells as a function of host platelet miRNAs. Altered genes comprised 548 up-regulated transcripts and 43 down-regulated transcripts, mostly mRNAs altogether spanning a variety of growth signaling pathways–notably pathways related to epithelial-mesenchymal transition—in tumor cells from platelet miRNA-deleted mice compared with those from control mice. Tumors in platelet miRNA-depleted mice showed more sarcomatoid growth and more advanced tumor grade, indicating roles for host platelet miRNAs in tumor plasticity. We further validated increased protein expression of selected genes associated with increased cognate mRNAs in the tumors due to platelet miRNA depletion in the host animals, providing proof of principle of widespread effects of platelet miRNAs on tumor cell functional gene expression in primary tumors in vivo. Together, these data demonstrate that platelet-derived miRNAs modulate solid tumor growth in vivo by broad-spectrum restructuring of the tumor cell transcriptome. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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216. Feasibility of Fitness Tracker Usage to Assess Activity Level and Toxicities in Patients With Colorectal Cancer.
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Ward, William H., Meeker, Caitlin R., Handorf, Elizabeth, Hill, Maureen V., Einarson, Margret, Alpaugh, R. Katherine, Holden, Thomas L., Astsaturov, Igor, Denlinger, Crystal S., Hall, Michael J., Reddy, Sanjay S., Sigurdson, Elin R., Dotan, Efrat, Zibelman, Matthew, Meyer, Joshua E., Farma, Jeffrey M., and Vijayvergia, Namrata
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COLORECTAL cancer , *CANCER patients , *MEDICAL needs assessment , *PHYSICAL activity , *SURGICAL complications , *SURGICAL equipment , *EXERCISE tolerance , *PATIENT readmissions - Abstract
PURPOSE: Performance status (PS) is a subjective assessment of patients' overall health. Quantification of physical activity using a wearable tracker (Fitbit Charge [FC]) may provide an objective measure of patient's overall PS and treatment tolerance. MATERIALS AND METHODS: Patients with colorectal cancer were prospectively enrolled into two cohorts (medical and surgical) and asked to wear FC for 4 days at baseline (start of new chemotherapy [± 4 weeks] or prior to curative resection) and follow-up (4 weeks [± 2 weeks] after initial assessment in medical and postoperative discharge in surgical cohort). Primary end point was feasibility, defined as 75% of patients wearing FC for at least 12 hours/d, 3 of 4 assigned days. Mean steps per day (SPD) were correlated with toxicities of interest (postoperative complication or ≥ grade 3 toxicity). A cutoff of 5,000 SPD was selected to compare outcomes. RESULTS: Eighty patients were accrued over 3 years with 55% males and a median age of 59.5 years. Feasibility end point was met with 68 patients (85%) wearing FC more than predefined duration and majority (91%) finding its use acceptable. The mean SPD count for patients with PS 0 was 6,313, and for those with PS 1, it was 2,925 (122 and 54 active minutes, respectively) (P =.0003). Occurrence of toxicity of interest was lower among patients with SPD > 5,000 (7 of 33, 21%) compared with those with SPD < 5,000 (14 of 43, 32%), although not significant (P =.31). CONCLUSION: Assessment of physical activity with FC is feasible in patients with colorectal cancer and well-accepted. SPD may serve as an adjunct to PS assessment and a possible tool to help predict toxicities, regardless of type of therapy. Future studies incorporating FC can standardize patient assessment and help identify vulnerable population. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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217. TRPV1 Gates Tissue Access and Sustains Pathogenicity in Autoimmune Encephalitis.
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Paltser, Geoffrey, Xue Jun Liu, Yantha, Jason, Winer, Shawn, Hubert Tsui, Ping Wu, Yuko Maezawa, Cahill, Lindsay S., Laliberté, Christine L., Ramagopalan, Sreeram V., DeLuca, Gabriele C., Sadovnick, A. Dessa, Astsaturov, Igor, Ebers, George C., Henkelman, R. Mark, Salter, Michael W., and Dosch, H.-Michael
- Abstract
Multiple sclerosis (MS) is a chronic progressive, demyelinating condition whose therapeutic needs are unmet, and whose pathoetiology is elusive. We report that transient receptor potential vanilloid-1 (TRPV1) expressed in a major sensory neuron subset, controls severity and progression of experimental autoimmune encephalomyelitis (EAE) in mice and likely in primary progressive MS. TRPV1–/– B6 congenics are protected from EAE. Increased survival reflects reduced central nervous systems (CNS) infiltration, despite indistinguishable T cell autoreactivity and pathogenicity in the periphery of TRPV1-sufficient and -deficient mice. The TRPV1+ neurovascular complex defining the blood-CNS barriers promoted invasion of pathogenic lymphocytes without the contribution of TRPV1-dependent neuropeptides such as substance P. In MS patients, we found a selective risk-association of the missense rs877610 TRPV1 single nucleotide polymorphism (SNP) in primary progressive disease. Our findings indicate that TRPV1 is a critical disease modifier in EAE, and we identify a predictor of severe disease course and a novel target for MS therapy. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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218. Analyses of DNA repair protein expression in BRCA1 mutant patient-derived xenografts.
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Huelsmann, Erica, Krais, John, Clausen, Emma, Khazak, Vladimir, Astsaturov, Igor, Swisher, Elizabeth, and Johnson, Neil
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DNA analysis , *BRCA genes , *DNA repair , *PROTEIN expression , *GENETIC recombination , *LABORATORY mice , *OVARIAN epithelial cancer - Abstract
To evaluate the potential of DNA damage response protein expression and foci formation to serve as biomarkers of resistance to platinum chemotherpay or Poly-(ADP)-Ribose Polymerase Inhibitors (PARPi) using immunohistochemistry (IHC). A collection of four patient-derived xenografts (PDX) mouse models with BRCA1 mutations in exon 11, a BRCA1 exon 13 mutant, and a BRCA1 wild-type tumor were analyzed. BRCA1 exon 11 mutants included: PDX196, mutation: c1961delA; PDX124, mutation: c196delA; PDX017, mutation: c1105_1106insTC; PDX056, mutation: c895_896delGT; BRCA1 WT control: PDX036 and BRCA1 exon 13 mutant: PDX1126, mutation: c4327C>T. Mice harboring PDX tumors were subjected to vehicle, PARPi (rucaparib), or platinum (cisplatin) treatment. Passaging and re-treatment of tumors was performed until minimal therapy response. Formalin-fixed paraffin embedded tumor samples was prepared for IHC analyses. IHC protocols were optimized to evaluate expression and foci formation for the following proteins: phosphorylated-RPA32, Rad51, phosphorylated-53BP1, 53BP1, BRCA1, Ki67. BRCA1 foci formation was observed by IHC in PARPi and cisplatin resistant tumors. Reversion mutations were not detected and BRCA1 protein expression was due to increased levels of BRCA1 -D11q. Increased RPA32 and RAD51 foci were also observed in several therapy resistant PDX models, which indicate active HR repair. Interestingly, acquired resistance to cisplatin and PARPi was associated with a reduction in 53BP1 and phosphorylated-53BP1. Finally, PARPi and cisplatin resistant tumors exhibited similar levels of BRCA1 and RAD51 foci. BRCA1 -D11q protein expression correlates with platinum and PARPi response in several BRCA1 exon 11 mutant PDX models. We predict that increased BRCA1 -D11q in combination with decreased 53BP1 expression drives RPA and RAD51 foci, resulting in active homologous recombination and therapy resistance. Our results suggest that IHC can be utilized for detection of DNA damage repair protein expression as well as foci formation, and could lead to the development of biomarkers that are predictive of therapy response. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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219. Aurora kinases in head and neck cancer.
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Mehra, Ranee, Serebriiskii, Ilya G, Burtness, Barbara, Astsaturov, Igor, and Golemis, Erica A
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AURORA kinases , *SQUAMOUS cell carcinoma , *BIOMARKERS , *CLINICAL trials , *HEAD & neck cancer treatment - Abstract
Summary: In healthy cells, controlled activation of aurora kinases regulates mitosis. Overexpression and hyperactivation of aurora kinases A and B have major roles in tumorigenesis, and can induce aneuploidy and genomic instability. In squamous-cell carcinomas of the head and neck, overexpression of aurora kinase A is associated with decreased survival, and a reduction in aurora kinase A and aurora kinase B expression inhibits cell growth and increases apoptosis. In this Review, we provide an overview of the biological functions of aurora kinases in healthy cells and in cancer cells, and we review small studies and high-throughput datasets that particularly implicate aurora kinase A in the pathogenesis of squamous-cell carcinomas of the head and neck. Early phase trials are beginning to assess the activity of small-molecule inhibitors of aurora kinases. We summarise trials of aurora kinase inhibitors in squamous-cell carcinomas of the head and neck, and discuss directions for future drug combination trials and biomarkers to use with drugs that inhibit aurora kinases. [Copyright &y& Elsevier]
- Published
- 2013
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220. Protocol for isolating extracellular vesicles from pancreatic cancer cells for liver metastatic niche research.
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Casabianca A, Bellina M, Dudgeon C, Nezhad MS, Harris C, Fiore S, Bernet A, Narrow W, Prela O, Wang L, Astsaturov I, Mehlen P, and Carpizo DR
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- Animals, Mice, Humans, Cell Line, Tumor, Pancreatic Neoplasms pathology, Pancreatic Neoplasms metabolism, Extracellular Vesicles metabolism, Liver Neoplasms secondary, Liver Neoplasms pathology, Liver Neoplasms metabolism
- Abstract
Extracellular vesicles (EVs) are secreted, cell-derived, membrane-bound compartments implicated in various diseases for their ability to influence distant targets and as carriers of biomarkers. Here, we present a protocol for separating EVs from mammalian pancreatic cancer cells and their characterization using western blot and electron microscopy. We then demonstrate how they are utilized to affect tumor development in a murine model of metastatic pancreatic cancer including a method to quantify hepatic tumor burden in histologic samples. For complete details on the use and execution of this protocol, please refer to Dudgeon et al.
1 ., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)- Published
- 2024
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221. Food Insecurity and Dietary Quality in African American Patients with Gastrointestinal Cancers: An Exploratory Study.
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Dratsky D, McGillivray E, Mittal J, Handorf EA, Berardi G, Astsaturov I, Hall MJ, Yeh MC, Jain R, and Fang CY
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- Humans, Male, Female, Middle Aged, Cross-Sectional Studies, Aged, Adult, Diet, Healthy statistics & numerical data, Food Insecurity, Gastrointestinal Neoplasms, Black or African American statistics & numerical data, Diet statistics & numerical data
- Abstract
African American (AA) individuals experience food insecurity at twice the rate of the general population. However, few patients are screened for these measures in the oncology setting. The primary aim of this study was to evaluate associations between food insecurity and dietary quality in AA patients with gastrointestinal (GI) malignancies. The secondary aim was to evaluate differences in dietary quality and the level of food insecurity between the participants at Temple University Hospital (TUH) vs. Fox Chase Cancer Center (FCCC). A single-arm, cross-sectional study was conducted, in which 40 AA patients with GI malignancies were recruited at FCCC and TUH between February 2021 and July 2021. Participants completed the US Adult Food Security Survey Module to assess the level of food security (food secure vs. food insecure). An electronic food frequency questionnaire (VioScreen
TM ) was administered to obtain usual dietary intake. Diet quality was calculated using the Healthy Eating Index 2015 (HEI-2015). Dietary quality and food insecurity were summarized using standard statistical measures. Overall, 6 of the 40 participants (15%) reported food insecurity, and the mean HEI-2015 score was 64.2. No association was observed between dietary quality and food insecurity ( p = 0.29). However, we noted that dietary quality was significantly lower among patients presenting at TUH (mean HEI-2015 = 57.8) compared to patients at FCCC (mean HEI-2015 = 73.5) ( p < 0.01). Food insecurity scores were also significantly higher in the TUH population vs. the FCCC population ( p < 0.01).- Published
- 2024
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222. Netrin-1 feedforward mechanism promotes pancreatic cancer liver metastasis via hepatic stellate cell activation, retinoid, and ELF3 signaling.
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Dudgeon C, Casabianca A, Harris C, Ogier C, Bellina M, Fiore S, Bernet A, Ducarouge B, Goldschneider D, Su X, Pitarresi J, Hezel A, De S, Narrow W, Soliman F, Shields C, Vendramini-Costa DB, Prela O, Wang L, Astsaturov I, Mehlen P, and Carpizo DR
- Subjects
- Humans, Netrin-1, Retinoids, Hepatic Stellate Cells metabolism, Cell Line, Tumor, Netrin Receptors, DNA-Binding Proteins, Transcription Factors, Proto-Oncogene Proteins c-ets, Pancreatic Neoplasms pathology, Carcinoma, Pancreatic Ductal pathology, Liver Neoplasms metabolism
- Abstract
The biology of metastatic pancreatic ductal adenocarcinoma (PDAC) is distinct from that of the primary tumor due to changes in cell plasticity governed by a distinct transcriptome. Therapeutic strategies that target this distinct biology are needed. We detect an upregulation of the neuronal axon guidance molecule Netrin-1 in PDAC liver metastases that signals through its dependence receptor (DR), uncoordinated-5b (Unc5b), to facilitate metastasis in vitro and in vivo. The mechanism of Netrin-1 induction involves a feedforward loop whereby Netrin-1 on the surface of PDAC-secreted extracellular vesicles prepares the metastatic niche by inducing hepatic stellate cell activation and retinoic acid secretion that in turn upregulates Netrin-1 in disseminated tumor cells via RAR/RXR and Elf3 signaling. While this mechanism promotes PDAC liver metastasis, it also identifies a therapeutic vulnerability, as it can be targeted using anti-Netrin-1 therapy to inhibit metastasis using the Unc5b DR cell death mechanism., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)
- Published
- 2023
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223. Conditional Dependency of LP-184 on Prostaglandin Reductase 1 is Synthetic Lethal in Pancreatic Cancers with DNA Damage Repair Deficiencies.
- Author
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Restifo D, McDermott JR, Cvetkovic D, Dos Santos T, Ogier C, Surumbayeva A, Handorf EA, Schimke C, Ma C, Cai KQ, Olszanski AJ, Kathad U, Bhatia K, Sharma P, Kulkarni A, and Astsaturov I
- Subjects
- Humans, DNA Repair, Animals, Adenocarcinoma, DNA Damage, Pancreatic Neoplasms drug therapy, Pancreatic Neoplasms genetics, Alcohol Oxidoreductases genetics, Antineoplastic Agents pharmacology
- Abstract
The greater efficacy of DNA-damaging drugs for pancreatic adenocarcinoma (PDAC) relies on targeting cancer-specific vulnerabilities while sparing normal organs and tissues due to their inherent toxicities. We tested LP-184, a novel acylfulvene analog, for its activity in preclinical models of PDAC carrying mutations in the DNA damage repair (DDR) pathways. Cytotoxicity of LP-184 is solely dependent on prostaglandin reductase 1 (PTGR1), so that PTGR1 expression robustly correlates with LP-184 cytotoxicity in vitro and in vivo. Low-passage patient-derived PDAC xenografts with DDR deficiencies treated ex vivo are more sensitive to LP-184 compared with DDR-proficient tumors. Additional in vivo testing of PDAC xenografts for their sensitivity to LP-184 demonstrates marked tumor growth inhibition in models harboring pathogenic mutations in ATR, BRCA1, and BRCA2. Depletion of PTGR1, however, completely abrogates the antitumor effect of LP-184. Testing combinatorial strategies for LP-184 aimed at deregulation of nucleotide excision repair proteins ERCC3 and ERCC4 established synergy. Our results provide valuable biomarkers for clinical testing of LP-184 in a large subset of genetically defined characterized refractory carcinomas. High PTGR1 expression and deleterious DDR mutations are present in approximately one third of PDAC making these patients ideal candidates for clinical trials of LP-184., (©2023 American Association for Cancer Research.)
- Published
- 2023
- Full Text
- View/download PDF
224. Trogocytosis of cancer-associated fibroblasts promotes pancreatic cancer growth and immune suppression via phospholipid scramblase anoctamin 6 (ANO6).
- Author
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Ogier C, Solomon AMC, Lu Z, Recoules L, Klochkova A, Gabitova-Cornell L, Bayarmagnai B, Restifo D, Surumbayeva A, Vendramini-Costa DB, Deneka AY, Francescone R, Lilly AC, Sipman A, Gardiner JC, Luong T, Franco-Barraza J, Ibeme N, Cai KQ, Einarson MB, Nicolas E, Efimov A, Megill E, Snyder NW, Bousquet C, Cros J, Zhou Y, Golemis EA, Gligorijevic B, Soboloff J, Fuchs SY, Cukierman E, and Astsaturov I
- Abstract
In pancreatic ductal adenocarcinoma (PDAC), the fibroblastic stroma constitutes most of the tumor mass and is remarkably devoid of functional blood vessels. This raises an unresolved question of how PDAC cells obtain essential metabolites and water-insoluble lipids. We have found a critical role for cancer-associated fibroblasts (CAFs) in obtaining and transferring lipids from blood-borne particles to PDAC cells via trogocytosis of CAF plasma membranes. We have also determined that CAF-expressed phospholipid scramblase anoctamin 6 (ANO6) is an essential CAF trogocytosis regulator required to promote PDAC cell survival. During trogocytosis, cancer cells and CAFs form synapse-like plasma membranes contacts that induce cytosolic calcium influx in CAFs via Orai channels. This influx activates ANO6 and results in phosphatidylserine exposure on CAF plasma membrane initiating trogocytosis and transfer of membrane lipids, including cholesterol, to PDAC cells. Importantly, ANO6-dependent trogocytosis also supports the immunosuppressive function of pancreatic CAFs towards cytotoxic T cells by promoting transfer of excessive amounts of cholesterol. Further, blockade of ANO6 antagonizes tumor growth via disruption of delivery of exogenous cholesterol to cancer cells and reverses immune suppression suggesting a potential new strategy for PDAC therapy.
- Published
- 2023
- Full Text
- View/download PDF
225. Intrapancreatic fat, pancreatitis, and pancreatic cancer.
- Author
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Lilly AC, Astsaturov I, and Golemis EA
- Subjects
- Mice, Animals, Pancreas pathology, Acinar Cells pathology, Tumor Microenvironment, Pancreatic Neoplasms, Pancreatic Neoplasms pathology, Pancreatitis pathology, Carcinoma, Pancreatic Ductal pathology
- Abstract
Pancreatic cancer is typically detected at an advanced stage, and is refractory to most forms of treatment, contributing to poor survival outcomes. The incidence of pancreatic cancer is gradually increasing, linked to an aging population and increasing rates of obesity and pancreatitis, which are risk factors for this cancer. Sources of risk include adipokine signaling from fat cells throughout the body, elevated levels of intrapancreatic intrapancreatic adipocytes (IPAs), inflammatory signals arising from pancreas-infiltrating immune cells and a fibrotic environment induced by recurring cycles of pancreatic obstruction and acinar cell lysis. Once cancers become established, reorganization of pancreatic tissue typically excludes IPAs from the tumor microenvironment, which instead consists of cancer cells embedded in a specialized microenvironment derived from cancer-associated fibroblasts (CAFs). While cancer cell interactions with CAFs and immune cells have been the topic of much investigation, mechanistic studies of the source and function of IPAs in the pre-cancerous niche are much less developed. Intriguingly, an extensive review of studies addressing the accumulation and activity of IPAs in the pancreas reveals that unexpectedly diverse group of factors cause replacement of acinar tissue with IPAs, particularly in the mouse models that are essential tools for research into pancreatic cancer. Genes implicated in regulation of IPA accumulation include KRAS, MYC, TGF-β, periostin, HNF1, and regulators of ductal ciliation and ER stress, among others. These findings emphasize the importance of studying pancreas-damaging factors in the pre-cancerous environment, and have significant implications for the interpretation of data from mouse models for pancreatic cancer., (© 2023. The Author(s).)
- Published
- 2023
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226. Tumor-Suppressive and Immune-Stimulating Roles of Cholesterol 25-hydroxylase in Pancreatic Cancer Cells.
- Author
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McBrearty N, Cho C, Chen J, Zahedi F, Peck AR, Radaelli E, Assenmacher CA, Pavlak C, Devine A, Yu P, Lu Z, Zhang H, Li J, Pitarresi JR, Astsaturov I, Cukierman E, Rustgi AK, Stanger BZ, Rui H, and Fuchs SY
- Subjects
- Animals, Humans, Mice, Mice, Knockout, Carcinoma, Pancreatic Ductal pathology, Pancreatic Neoplasms pathology, Steroid Hydroxylases metabolism
- Abstract
Cholesterol dependence is an essential characteristic of pancreatic ductal adenocarcinoma (PDAC). Cholesterol 25-hydroxylase (CH25H) catalyzes monooxygenation of cholesterol into 25-hydroxycholesterol, which is implicated in inhibiting cholesterol biosynthesis and in cholesterol depletion. Here, we show that, within PDAC cells, accumulation of cholesterol was facilitated by the loss of CH25H. Methylation of the CH25H gene and decreased levels of CH25H expression occurred in human pancreatic cancers and was associated with poor prognosis. Knockout of Ch25h in mice accelerated progression of Kras-driven pancreatic intraepithelial neoplasia. Conversely, restoration of CH25H expression in human and mouse PDAC cells decreased their viability under conditions of cholesterol deficit, and decelerated tumor growth in immune competent hosts. Mechanistically, the loss of CH25H promoted autophagy resulting in downregulation of MHC-I and decreased CD8+ T-cell tumor infiltration. Re-expression of CH25H in PDAC cells combined with immune checkpoint inhibitors notably inhibited tumor growth. We discuss additional benefits that PDAC cells might gain from inactivation of CH25H and the potential translational importance of these findings for therapeutic approaches to PDAC., Implications: Loss of CH25H by pancreatic cancer cells may stimulate tumor progression and interfere with immunotherapies., (©2022 American Association for Cancer Research.)
- Published
- 2023
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227. Large-scale analysis of KMT2 mutations defines a distinctive molecular subset with treatment implication in gastric cancer.
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Wang J, Xiu J, Baca Y, Battaglin F, Arai H, Kawanishi N, Soni S, Zhang W, Millstein J, Salhia B, Goldberg RM, Philip PA, Seeber A, Hwang JJ, Shields AF, Marshall JL, Astsaturov I, Craig Lockhart A, Gatalica Z, Michael Korn W, and Lenz HJ
- Subjects
- Aged, Aged, 80 and over, DNA Mismatch Repair, DNA Mutational Analysis, Databases, Genetic, Female, Gene Frequency, Histone-Lysine N-Methyltransferase metabolism, Humans, Kaplan-Meier Estimate, Male, Microsatellite Instability, Middle Aged, Neoplasm Grading, Neoplasm Staging, Prognosis, Stomach Neoplasms drug therapy, Stomach Neoplasms metabolism, Tumor Microenvironment, Biomarkers, Tumor, Histone-Lysine N-Methyltransferase genetics, Isoenzymes genetics, Mutation, Stomach Neoplasms diagnosis, Stomach Neoplasms genetics
- Abstract
Frequent mutations of genes in the histone-lysine N-methyltransferase 2 (KMT2) family members were identified in gastric cancers (GCs). Understanding how gene mutations of KMT2 family affect cancer progression and tumor immune microenvironment may provide new treatment strategies. A total of 1245 GCs were analyzed using next-generation sequencing, whole transcriptome sequencing, immunohistochemistry (Caris Life Sciences, Phoenix, AZ). The overall mutation rate of genes in the KMT2 family was 10.6%. Compared to KMT2-wild-type GCs, genes involved in epigenetic modification, receptor tyrosine kinases/MAPK/PI3K, and DNA damage repair (DDR) pathways had higher mutation rates in KMT2-mutant GCs (p < 0.05). Significantly higher rates of high tumor mutational burden, microsatellite instability-high/mismatch-repair deficiency (dMMR), and PD-L1 positivity were observed in KMT2-mutant GCs (p < 0.01), compared to KMT2-wild-type GCs. The association between PD-L1 positivity and KMT2 mutations remained significant in the proficient-MMR and microsatellite stable subgroup. Based on transcriptome data from the TCGA, cell cycle, metabolism, and interferon-α/β response pathways were significantly upregulated in KMT2-mutant GCs than in KMT2-wild-type GCs. Patients with KMT2 mutation treated with immune checkpoint inhibitors had longer median overall survival compared to KMT2-wild-type patients with metastatic solid tumors (35 vs. 16 months, HR = 0.73, 95% CI: 0.62-0.87, p = 0.0003). In conclusion, this is the largest study to investigate the distinct molecular features between KMT2-mutant and KMT2-wild-type GCs to date. Our data indicate that GC patients with KMT2 mutations may benefit from ICIs and drugs targeting DDR, MAPK/PI3K, metabolism, and cell cycle pathways., (© 2021. The Author(s), under exclusive licence to Springer Nature Limited.)
- Published
- 2021
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228. A framework for advancing our understanding of cancer-associated fibroblasts.
- Author
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Sahai E, Astsaturov I, Cukierman E, DeNardo DG, Egeblad M, Evans RM, Fearon D, Greten FR, Hingorani SR, Hunter T, Hynes RO, Jain RK, Janowitz T, Jorgensen C, Kimmelman AC, Kolonin MG, Maki RG, Powers RS, Puré E, Ramirez DC, Scherz-Shouval R, Sherman MH, Stewart S, Tlsty TD, Tuveson DA, Watt FM, Weaver V, Weeraratna AT, and Werb Z
- Subjects
- Animals, Biomarkers, Cancer-Associated Fibroblasts drug effects, Cell Plasticity, Clinical Trials as Topic, Disease Susceptibility, Humans, Molecular Targeted Therapy, Neoplasms drug therapy, Neoplasms metabolism, Signal Transduction, Stromal Cells drug effects, Stromal Cells metabolism, Stromal Cells pathology, Treatment Outcome, Cancer-Associated Fibroblasts metabolism, Cancer-Associated Fibroblasts pathology, Neoplasms etiology, Neoplasms pathology, Tumor Microenvironment
- Abstract
Cancer-associated fibroblasts (CAFs) are a key component of the tumour microenvironment with diverse functions, including matrix deposition and remodelling, extensive reciprocal signalling interactions with cancer cells and crosstalk with infiltrating leukocytes. As such, they are a potential target for optimizing therapeutic strategies against cancer. However, many challenges are present in ongoing attempts to modulate CAFs for therapeutic benefit. These include limitations in our understanding of the origin of CAFs and heterogeneity in CAF function, with it being desirable to retain some antitumorigenic functions. On the basis of a meeting of experts in the field of CAF biology, we summarize in this Consensus Statement our current knowledge and present a framework for advancing our understanding of this critical cell type within the tumour microenvironment.
- Published
- 2020
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- View/download PDF
229. Future Clinical Trials: Genetically Driven Trials.
- Author
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Astsaturov I
- Subjects
- Humans, Medical Oncology methods, Molecular Targeted Therapy methods, Neoplasms diagnosis, Neoplasms drug therapy, Pharmacogenetics, Treatment Outcome, Biomarkers, Tumor genetics, Medical Oncology trends, Molecular Targeted Therapy trends, Neoplasms genetics, Precision Medicine trends
- Abstract
The design of modern oncology clinical trials seeks to match patients' cancer molecular biomarkers with medications that specifically target those biomarkers, a general paradigm shift in cancer care coined clinical cancer biology. This approach exploits the synthetic lethality between a specific genetic alteration in the cancer cell and a drug: rapid termination of exaggerated kinase activity exemplifies this phenomenon. Synthetic lethality-based investigations are driven by rapidly evolving technologies for cancer molecular profiling. As these technologies evolve, future clinical trials will test drugs' activity based on the molecular mechanisms rather than by the tumor's appearance under a microscope., (Copyright © 2017 Elsevier Inc. All rights reserved.)
- Published
- 2017
- Full Text
- View/download PDF
230. Targeted delivery of chemotherapy using HSP90 inhibitor drug conjugates is highly active against pancreatic cancer models.
- Author
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Bobrov E, Skobeleva N, Restifo D, Beglyarova N, Cai KQ, Handorf E, Campbell K, Proia DA, Khazak V, Golemis EA, and Astsaturov I
- Subjects
- Animals, Antineoplastic Agents pharmacology, Camptothecin administration & dosage, Camptothecin pharmacology, Carcinoma, Pancreatic Ductal genetics, Carcinoma, Pancreatic Ductal metabolism, Cell Cycle drug effects, Cell Line, Tumor, DNA Damage, Humans, Mice, Molecular Targeted Therapy, Pancreatic Neoplasms genetics, Pancreatic Neoplasms metabolism, Proto-Oncogene Proteins p21(ras) genetics, Resorcinols pharmacology, Tumor Suppressor Protein p53 genetics, Xenograft Model Antitumor Assays, Antineoplastic Agents administration & dosage, Camptothecin analogs & derivatives, Carcinoma, Pancreatic Ductal drug therapy, Pancreatic Neoplasms drug therapy, Resorcinols administration & dosage
- Abstract
The lack of effective treatment modalities is a major problem in pancreatic cancer (PCa), a devastating malignancy that is nearly universally driven by the "undruggable" KRAS and TP53 cancer genes. Poor tumor tissue penetration is the major source of resistance in pancreatic cancer where chemotherapy is the mainstay of treatment. In this study we exploited the selective tumor-targeting properties of the heat shock 90 protein inhibitors as the vehicle for drug delivery to pancreatic tumor tissues. STA-12-8666 is a novel esterase-cleavable conjugate of an HSP90i and a topoisomerase I inhibitor, SN-38. STA-12-8666 selectively binds activated HSP90 and releases its cytotoxic payload resulting in drug accumulation in pancreatic cancer cells in vivo. We investigated the preclinical activity of STA-12-8666 in patient derived xenograft and genetic models of pancreatic cancer.Treatment with STA-12-8666 of the KPC mice (knock-in alleles of LSL-KrasG12D, Tp53fl/fl and Pdx1-Cre transgene) at the advanced stages of pancreatic tumors doubled their survival (49 days vs. 74 days, p=0.008). STA-12-8666 also demonstrated dramatically superior activity in comparison to equimolar doses of irinotecan against 5 patient-derived pancreatic adenocarcinoma xenografts with prolonged remissions in some tumors. Analysis of activity of STA-12-8666 against tumor tissues and matched cell lines demonstrated prolonged accumulation and release of cytotoxic payload in the tumor leading to DNA damage response and cell cycle arrest.Our results provide a proof-of-principle validation that HSP90i-based drug conjugates can overcome the notorious treatment resistance by utilizing the inherently high affinity of pancreatic cancer cells to HSP90 antagonists.
- Published
- 2017
- Full Text
- View/download PDF
231. Successful imatinib therapy for neuroendocrine carcinoma with activating Kit mutation: a case study.
- Author
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Perkins J, Boland P, Cohen SJ, Olszanski AJ, Zhou Y, Engstrom P, and Astsaturov I
- Subjects
- Carcinoma, Neuroendocrine genetics, Carcinoma, Neuroendocrine pathology, Drug Resistance, Neoplasm genetics, Gastrointestinal Stromal Tumors genetics, Gastrointestinal Stromal Tumors pathology, Humans, Imatinib Mesylate, Kinesins antagonists & inhibitors, Male, Middle Aged, Signal Transduction, Benzamides administration & dosage, Carcinoma, Neuroendocrine drug therapy, Gastrointestinal Stromal Tumors drug therapy, Piperazines administration & dosage, Proto-Oncogene Proteins c-kit genetics, Pyrimidines administration & dosage
- Abstract
Neuroendocrine tumors (NET) and gastrointestinal stromal tumors (GIST) are believed to originate from the cells of Cajal that are randomly dispersed along the aerodigestive tract. Despite their distinct morphologic appearance, NET and GIST may share oncogenic mechanisms. Often presenting in the metastatic setting, treatment options for patients with NET are limited. This case report presents a patient with refractory metastatic NET that did not respond conventional chemotherapy. The patient was treated with a KIF11 inhibitor in a phase I clinical trial and experienced a prolonged and clinically meaningful partial response. On progression at 20 months, the patient's tumor was sequenced to reveal a KIT exon 11 mutation. Institution of imatinib therapy achieved a rapid and sustained antitumor effect with profound clinical benefit. Despite previously reported KIT expression in NET, this is the first documented case of an activating KIT mutation in NET and of successful treatment with both a KIF11 inhibitor and imatinib, each of which was elucidated through molecular profiling of the patient's tumor. Imatinib may be a valuable therapy in NET harboring activating KIT mutations., (Copyright © 2014 by the National Comprehensive Cancer Network.)
- Published
- 2014
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- View/download PDF
232. Chemotherapy and signaling: How can targeted therapies supercharge cytotoxic agents?
- Author
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Bagnyukova TV, Serebriiskii IG, Zhou Y, Hopper-Borge EA, Golemis EA, and Astsaturov I
- Subjects
- Antineoplastic Agents pharmacology, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Cell Death, Chemotherapy, Adjuvant, Drug Resistance, Neoplasm, Humans, Intracellular Signaling Peptides and Proteins metabolism, Microtubules drug effects, Neoplasms metabolism, Protein Kinases metabolism, RNA Interference, Antineoplastic Agents therapeutic use, Molecular Targeted Therapy, Neoplasms drug therapy, Signal Transduction drug effects
- Abstract
In recent years, oncologists have begun to conclude that chemotherapy has reached a plateau of efficacy as a primary treatment modality, even if toxicity can be effectively controlled. Emerging specific inhibitors of signaling and metabolic pathways (i.e., targeted agents) contrast with traditional chemotherapy drugs in that the latter primarily interfere with the DNA biosynthesis and the cell replication machinery. In an attempt to improve on the efficacy, combination of targeted drugs with conventional chemotherapeutics has become a routine way of testing multiple new agents in early phase clinical trials. This review discusses the recent advances including integrative systematic biology and RNAi approaches to counteract the chemotherapy resistance and to buttress the selectivity, efficacy and personalization of anti-cancer drug therapy.
- Published
- 2010
- Full Text
- View/download PDF
233. Clinical application of EGFR inhibitors in head and neck squamous cell cancer.
- Author
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Astsaturov I, Cohen RB, and Harari PM
- Subjects
- Animals, Carcinoma, Squamous Cell radiotherapy, Clinical Trials as Topic, Combined Modality Therapy, Drug Delivery Systems methods, ErbB Receptors drug effects, Head and Neck Neoplasms radiotherapy, Humans, Carcinoma, Squamous Cell drug therapy, ErbB Receptors antagonists & inhibitors, Head and Neck Neoplasms drug therapy
- Published
- 2008
234. Amplification of virus-induced antimelanoma T-cell reactivity by high-dose interferon-alpha2b: implications for cancer vaccines.
- Author
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Astsaturov I, Petrella T, Bagriacik EU, de Benedette M, Uger R, Lumber G, Berinstein N, Elias I, Iscoe N, Hammond C, Hamilton P, and Spaner DE
- Subjects
- Adult, Cell Division, Cytotoxicity, Immunologic, Enzyme-Linked Immunosorbent Assay, Female, HLA-A Antigens metabolism, HLA-A2 Antigen, Humans, Interferon alpha-2, Lymphatic Metastasis, Male, Melanocytes immunology, Melanocytes pathology, Melanoma secondary, Melanoma therapy, Membrane Glycoproteins genetics, Middle Aged, Neoplasm Proteins genetics, Recombinant Proteins, Vaccination, gp100 Melanoma Antigen, Antineoplastic Agents administration & dosage, Canarypox virus physiology, Cancer Vaccines administration & dosage, Interferon-alpha administration & dosage, Melanoma immunology, Membrane Glycoproteins immunology, Neoplasm Proteins immunology, T-Lymphocytes immunology
- Abstract
Purpose: The therapeutic effectiveness of cancer vaccines, composed of tumor antigens that are also self-antigens, may be limited by the normal mechanisms that preserve immunological tolerance. Consistent with this notion, we found that vaccination of melanoma patients with recombinant viral vaccines expressing gp100 (a melanoma antigen also expressed by normal melanocytes) produced only transient increases in noncytotoxic T cells specific for immunodominant gp100 epitopes. To improve the therapeutic effects of these vaccines, IFN-alpha2b (IFN-alpha) was administered to some high-risk patients., Experimental Design: 7 HLA-A*0201(+) patients were injected with high doses of IFN-alpha (20 MU/m(2) x 20 doses) at various times after completing the vaccination protocol. Clinical toxicity and responses were documented, and the effects on gp100-reactive T cells were measured by IFN-gamma enzyme-linked immunospot assays, tetramers of HLA-A*0201 and gp100 epitopes, and cellular cytotoxicity assays., Results: In patients who had previously responded to vaccination, high doses of IFN-alpha recalled gp100-reactive T cells with the ability to kill gp100-expressing tumor targets in vitro. Concomitant with the reappearance of these cytotoxic T cells, tumor regression was observed in the two patients with clinically evident metastatic disease., Conclusions: The finding that high-dose IFN recalls previously activated tumor-reactive T cells with potent killing ability suggests a strategy to maintain antitumor responses initiated by cancer vaccines.
- Published
- 2003
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