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Michael A Hollingsworth - One of the best experts on this subject based on the ideXlab platform.
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abstract 902 a small molecule glycomimetic antagonist of e selectin and cxcr4 gmi 1359 delays Pancreatic Tumor metastasis and significantly alters the Pancreatic Tumor microenvironment
Cancer Research, 2016Co-Authors: Maria M Steele, William E Fogler, John L Magnani, Michael A HollingsworthAbstract:The cellular and molecular composition of the Pancreatic Tumor microenvironment includes a complex matrix that encases Tumor cells and presents a conundrum in respect to therapy. The dense desmoplasia that accompanies Tumor growth reduces blood flow to Tumors and creates an environment that compromises delivery of therapeutics. As well, elimination of certain stromal elements enhances the aggressiveness and metastatic potential of Pancreatic cancer cells. Recent studies attempt to target stroma in an effort to enhance delivery and efficacy of therapeutic agents and to block metastasis. In this context we have investigated the activity of GMI-1359, a potent dual antagonist that targets both E-selectin and CXCR4. Adhesion protein E-selectin is crucial for regulating vascular and lymphatic endothelial cell (EC) interactions with Tumor cells during transmigration. The CXCL12-CXCR4 chemokine axis contributes to the formation of the Tumor microenvironment including fibroblast and immune cell recruitment, lymph- and angiogenesis, Tumor cell proliferation/survival, and Tumor stem cell mobilization. Our in vitro results demonstrate that Pancreatic fibroblasts secrete significant amounts of CXCL12 which promotes Tumor cell and lymphatic and vascular EC directional migration; this migration toward CXCL12-secreting fibroblasts was completely blocked by GMI-1359. Additionally, CXCL12-stimulated ECs facilitated increased transendothelial migration (TEM) by Pancreatic Tumor cells. Dual antagonist GMI-1359 inhibited this CXCL12-dependent increase in Pancreatic Tumor cell TEM and was more effective than an independent small molecule E-selectin only inhibitor. Using an in vivo orthotopic model of Pancreatic cancer in athymic mice, we evaluated the ability of GMI-1359 (with and without co-administration Gemcitabine (Gem)) to suppress Tumor progression, modulate Tumor microenvironment composition, and prolong survival. Our work demonstrated GMI-1359 slightly inhibited Tumor growth when used alone or in combination with Gem but did not prolong survival in this immune compromised model. However, GMI-1359 inhibited Tumor metastasis to the spleen, liver, and lungs. Interestingly, GMI-1359 significantly modulated the cellular composition of the Tumor microenvironment. Immunohistochemical analysis revealed mice treated with GMI-1359 (with or without Gem administration) had drastically reduced desmoplasia and reduced lymphatic and blood vessel densities compared to mice treated with vehicle control or Gem alone. The E-selectin only inhibitor had no effect on Tumor microenvironment composition. Further studies of GMI-1359, particularly in immune competent models, are warranted to understand its potential for disrupting the Pancreatic Tumor microenvironment, inhibiting dissemination, and enhancing anti-Tumor immune responses. Citation Format: Maria M. Steele, William E. Fogler, John L. Magnani, Michael A. Hollingsworth. A small molecule glycomimetic antagonist of E-selectin and CXCR4 (GMI-1359) delays Pancreatic Tumor metastasis and significantly alters the Pancreatic Tumor microenvironment. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 902.
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abstract 425 a small molecule glycomimetic antagonist of e selectin and cxcr4 gmi 1359 prevents Pancreatic Tumor metastasis and improves chemotherapy
Cancer Research, 2015Co-Authors: Maria M Steele, William E Fogler, John L Magnani, Michael A HollingsworthAbstract:The Tumor microenvironment9s cellular and molecular composition includes a complex matrix that encases Tumor cells and presents a conundrum in respect to Pancreatic Tumor therapy. On one hand, the dense desmoplastic reaction that accompanies growth of well differentiated Pancreatic Tumors reduces blood flow to Tumors and creates an environment in which it is difficult to deliver therapies. On the other hand, elimination of certain stromal elements enhances the aggressiveness and metastatic potential of Pancreatic cancer cells. Several current studies are attempting to target stroma in an effort to enhance delivery and efficacy of therapeutic agents and to block metastasis. We have investigated the activity of GMI-1359, a potent dual antagonist that targets both E-selectin and CXCR4. Adhesion protein E-selectin plays an important role in the Tumor microenvironment by regulating cell contacts, including Tumor cell binding to vascular and lymphatic endothelial cells during extravasation. Chemokine receptor CXCR49s role in the chemoattraction of Tumor cells toward endothelial cells (ECs) contributes to Tumor microenvironment remodeling by influencing lymphangiogenesis/angiogenesis, Tumor cell survival/proliferation, and Tumor stem cell mobilization. Our in vitro studies show that Pancreatic ductal adenocarcinoma (PDAC) cells do not attract growth of lymphatic nor vascular ECs toward themselves. However, Tumor associated fibroblasts, a major component of the PDAC Tumor microenvironment, significantly increase EC directional migration. GMI-1359 completely blocked lymphatic and vascular EC migration toward fibroblast cells and disrupted these cell-cell interactions. In addition, GMI-1359 inhibited the capacity of invasive PDAC cell lines S2.013 and Colo357 to bind and migrate across EC barriers. The dual antagonist was more effective than an independent small molecule E-selectin inhibitor. We evaluated the capacity of GMI-1359 to inhibit growth and metastasis of orthotopically implanted S2.013 cells with and without administration of Gemcitabine. Two weeks post implantation, mice were treated by intraperitoneal injection for 4 weeks with either PBS once daily; 40 mg/kg GMI-1359 once daily; 100 mg/kg Gemcitabine every 4 days; or a combination of GMI-1359 and Gemcitabine. GMI-1359 treatment slightly, but not significantly, decreased primary Tumor size as compared to the vehicle control. However, GMI-1359 in combination with Gemcitabine significantly reduced metastasis of this Tumor to liver and diaphragm as compared to mice that received only Gemcitabine. Further studies of GMI-1359 are warranted to understand its potential for disrupting cellular contacts and blocking Pancreatic Tumor dissemination through the vascular and lymphatic systems, and for enhancing the efficacy of chemotherapeutic approaches to Pancreatic cancer. Citation Format: Maria M. Steele, William E. Fogler, John L. Magnani, Michael A. Hollingsworth. A small molecule glycomimetic antagonist of E-selectin and CXCR4 (GMI-1359) prevents Pancreatic Tumor metastasis and improves chemotherapy. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 425. doi:10.1158/1538-7445.AM2015-425
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abstract 4503 a small molecule glycomimetic antagonist of e selectin gmi 1271 prevents Pancreatic Tumor metastasis and offers a novel treatment for improved efficacy of chemotherapy
Cancer Research, 2014Co-Authors: Maria M Steele, John L Magnani, Prakash Radhakrishnan, Michael A HollingsworthAbstract:The processes of intra- and extravasation of Tumor cells into and out of the blood and lymphatic systems are crucial steps during metastasis to distant organ sites. These processes are tightly regulated by the initial binding of sialyl Lewis A and sialyl Lewis X (sialyl Le A/X) carbohydrate moeities found on Tumor cells to the adhesion protein E-selectin expressed on the activated endothelium. GMI-1271 is a small molecule glycomimetic rationally designed based on the bioactive conformation of sialyl Lea/x and is a potent and specific antagonist of E-selectin. In vitro treatment of human lymphatic endothelial cells with GMI-1271 resulted in a decrease in the number of sialyl Lewis A-expressing Pancreatic cancer cells (S2.013 and BxPC-3) binding to the endothelium in a dose-dependent manner. GMI-1271 treatment also inhibited the transendothelial migration of S2.013 and BxPC-3 cells through a lymphatic cell monolayer. We evaluated the in vivo efficacy of GMI-1271 following orthotopic implantation of Pancreatic Tumor cell line S2.013, which expresses high levels of sialyl Lewis A (CA19-9), into nude mice. Following 2 weeks of Tumor growth, mice were treated by intraperitoneal injections for 4 weeks with either PBS once daily, once daily with 40mg/kg GMI-1271 (low dose), twice daily with 40mg/kg GMI-1271 (high dose), twice a week with 60mg/kg gemcitabine injections, combination low dose GMI-1271 and gemcitabine injections, or combination high dose GMI-1271 and gemcitabine injections. Co-treatment of either low or high dose GMI-1271 with gemcitabine resulted in a significant decrease in the number of metastasis to the lymph nodes (p=0.02 low dose; p=0.04 high dose). In addition, compared with gemcitabine alone, low dose GMI-1271 plus gemcitabine was found to be effective at reducing the number of metastatic lesions (per histological section) in the liver (p=0.001), lung (p=0.026) and diaphragm (p=0.01). Based on the significant effects of combination therapy on Tumor metastasis, the small molecule glycomimetic antagonist to E-selectin, GMI-1271, offers great promise in preventing Pancreatic Tumor cell entry into the blood and lymphatic systems and offers a novel treatment for the improved efficacy of standard chemotherapy. Citation Format: Maria M. Steele, Prakash Radhakrishnan, John L. Magnani, Michael A. Hollingsworth. A small molecule glycomimetic antagonist of E-selectin (GMI-1271) prevents Pancreatic Tumor metastasis and offers a novel treatment for improved efficacy of chemotherapy. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4503. doi:10.1158/1538-7445.AM2014-4503
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P-selectin Expression in a Metastatic Pancreatic Tumor Cell Line (SUIT-2)
Cancer Research, 1997Co-Authors: Takeshi Iwamura, Norio Kitamura, Hideo Yamanari, Thomas Caffrey, Toshiaki Setoguchi, Michael A HollingsworthAbstract:The human Pancreatic Tumor cell line SUIT-2 was derived from a metastatic lesion in the liver of a patient with Pancreatic adenocarcinoma. SUIT-2 and clonal cell lines derived from it show spontaneous metastasis to lung and regional lymph nodes from s.c. nude mouse xenografts and were found to express P-selectin mRNA and protein. Surface expression of P-selectin protein was increased by exposure of the Pancreatic Tumor cells to thrombin, oxygen radicals, and trypsin, suggesting that common cellular mechanisms for regulating P-selectin surface expression exist among platelets, endothelial cells, and these Pancreatic Tumor cells. The finding that P-selectin is expressed by metastatic Pancreatic Tumor cells demonstrates that the range of cell types that express these adhesion molecules is broader than believed previously.
Amato J Giaccia - One of the best experts on this subject based on the ideXlab platform.
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the role of Tumor cell derived connective tissue growth factor ctgf ccn2 in Pancreatic Tumor growth
Cancer Research, 2009Co-Authors: Kevin L Bennewith, Xin Huang, Edward E Graves, Janine T Erler, Neeraja Kambham, Jonathan Feazell, George P Yang, Albert C Koong, Amato J GiacciaAbstract:Pancreatic cancer is highly aggressive and refractory to existing therapies. Connective tissue growth factor ( CTGF/CCN2 ) is a fibrosis-related gene that is thought to play a role in Pancreatic Tumor progression. However, CCN2 can be expressed in a variety of cell types, and the contribution of CCN2 derived from either Tumor cells or stromal cells as it affects the growth of Pancreatic Tumors is unknown. Using genetic inhibition of CCN2, we have discovered that CCN2 derived from Tumor cells is a critical regulator of Pancreatic Tumor growth. Pancreatic Tumor cells derived from CCN2 shRNA–expressing clones showed dramatically reduced growth in soft agar and when implanted s.c. We also observed a role for CCN2 in the growth of Pancreatic Tumors implanted orthotopically, with Tumor volume measurements obtained by positron emission tomography imaging. Mechanistically, CCN2 protects cells from hypoxia-mediated apoptosis, providing an in vivo selection for Tumor cells that express high levels of CCN2. We found that CCN2 expression and secretion was increased in hypoxic Pancreatic Tumor cells in vitro , and we observed colocalization of CCN2 and hypoxia in Pancreatic Tumor xenografts and clinical Pancreatic adenocarcinomas. Furthermore, we found increased CCN2 staining in clinical Pancreatic Tumor tissue relative to stromal cells surrounding the Tumor, supporting our assertion that Tumor cell–derived CCN2 is important for Pancreatic Tumor growth. Taken together, these data improve our understanding of the mechanisms responsible for Pancreatic Tumor growth and progression, and also indicate that CCN2 produced by Tumor cells represents a viable therapeutic target for the treatment of Pancreatic cancer. [Cancer Res 2009;69(3):775–84]
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The Role of Tumor Cell-Derived Connective Tissue Growth Factor (CTGF/CCN2) in Pancreatic Tumor Growth
Cancer research, 2009Co-Authors: Kevin L Bennewith, Xin Huang, Edward E Graves, Janine T Erler, Neeraja Kambham, Jonathan Feazell, George P Yang, Albert C Koong, Christine M. Ham, Amato J GiacciaAbstract:Pancreatic cancer is highly aggressive and refractory to existing therapies. Connective tissue growth factor ( CTGF/CCN2 ) is a fibrosis-related gene that is thought to play a role in Pancreatic Tumor progression. However, CCN2 can be expressed in a variety of cell types, and the contribution of CCN2 derived from either Tumor cells or stromal cells as it affects the growth of Pancreatic Tumors is unknown. Using genetic inhibition of CCN2, we have discovered that CCN2 derived from Tumor cells is a critical regulator of Pancreatic Tumor growth. Pancreatic Tumor cells derived from CCN2 shRNA–expressing clones showed dramatically reduced growth in soft agar and when implanted s.c. We also observed a role for CCN2 in the growth of Pancreatic Tumors implanted orthotopically, with Tumor volume measurements obtained by positron emission tomography imaging. Mechanistically, CCN2 protects cells from hypoxia-mediated apoptosis, providing an in vivo selection for Tumor cells that express high levels of CCN2. We found that CCN2 expression and secretion was increased in hypoxic Pancreatic Tumor cells in vitro , and we observed colocalization of CCN2 and hypoxia in Pancreatic Tumor xenografts and clinical Pancreatic adenocarcinomas. Furthermore, we found increased CCN2 staining in clinical Pancreatic Tumor tissue relative to stromal cells surrounding the Tumor, supporting our assertion that Tumor cell–derived CCN2 is important for Pancreatic Tumor growth. Taken together, these data improve our understanding of the mechanisms responsible for Pancreatic Tumor growth and progression, and also indicate that CCN2 produced by Tumor cells represents a viable therapeutic target for the treatment of Pancreatic cancer. [Cancer Res 2009;69(3):775–84]
Hyo Jeong Kuh - One of the best experts on this subject based on the ideXlab platform.
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microfluidic co culture of Pancreatic Tumor spheroids with stellate cells as a novel 3d model for investigation of stroma mediated cell motility and drug resistance
Journal of Experimental & Clinical Cancer Research, 2018Co-Authors: Ji Hyun Lee, Seul Ki Kim, Iftikhar Ali Khawar, Su Yeong Jeong, Seok Chung, Hyo Jeong KuhAbstract:Pancreatic stellate cells (PSCs), a major component of the Tumor microenvironment in Pancreatic cancer, play roles in cancer progression as well as drug resistance. Culturing various cells in microfluidic (microchannel) devices has proven to be a useful in studying cellular interactions and drug sensitivity. Here we present a microchannel plate-based co-culture model that integrates Tumor spheroids with PSCs in a three-dimensional (3D) collagen matrix to mimic the Tumor microenvironment in vivo by recapitulating epithelial-mesenchymal transition and chemoresistance. A 7-channel microchannel plate was prepared using poly-dimethylsiloxane (PDMS) via soft lithography. PANC-1, a human Pancreatic cancer cell line, and PSCs, each within a designated channel of the microchannel plate, were cultured embedded in type I collagen. Expression of EMT-related markers and factors was analyzed using immunofluorescent staining or Proteome analysis. Changes in viability following exposure to gemcitabine and paclitaxel were measured using Live/Dead assay. PANC-1 cells formed 3D Tumor spheroids within 5 days and the number of spheroids increased when co-cultured with PSCs. Culture conditions were optimized for PANC-1 cells and PSCs, and their appropriate interaction was confirmed by reciprocal activation shown as increased cell motility. PSCs under co-culture showed an increased expression of α-SMA. Expression of EMT-related markers, such as vimentin and TGF-β, was higher in co-cultured PANC-1 spheroids compared to that in mono-cultured spheroids; as was the expression of many other EMT-related factors including TIMP1 and IL-8. Following gemcitabine exposure, no significant changes in survival were observed. When paclitaxel was combined with gemcitabine, a growth inhibitory advantage was prominent in Tumor spheroids, which was accompanied by significant cytotoxicity in PSCs. We demonstrated that cancer cells grown as Tumor spheroids in a 3D collagen matrix and PSCs co-cultured in sub-millimeter proximity participate in mutual interactions that induce EMT and drug resistance in a microchannel plate. Microfluidic co-culture of Pancreatic Tumor spheroids with PSCs may serve as a useful model for studying EMT and drug resistance in a clinically relevant manner.
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Microfluidic co-culture of Pancreatic Tumor spheroids with stellate cells as a novel 3D model for investigation of stroma-mediated cell motility and drug resistance
BMC, 2018Co-Authors: Ji Hyun Lee, Seul Ki Kim, Iftikhar Ali Khawar, Su Yeong Jeong, Seok Chung, Hyo Jeong KuhAbstract:Abstract Background Pancreatic stellate cells (PSCs), a major component of the Tumor microenvironment in Pancreatic cancer, play roles in cancer progression as well as drug resistance. Culturing various cells in microfluidic (microchannel) devices has proven to be a useful in studying cellular interactions and drug sensitivity. Here we present a microchannel plate-based co-culture model that integrates Tumor spheroids with PSCs in a three-dimensional (3D) collagen matrix to mimic the Tumor microenvironment in vivo by recapitulating epithelial-mesenchymal transition and chemoresistance. Methods A 7-channel microchannel plate was prepared using poly-dimethylsiloxane (PDMS) via soft lithography. PANC-1, a human Pancreatic cancer cell line, and PSCs, each within a designated channel of the microchannel plate, were cultured embedded in type I collagen. Expression of EMT-related markers and factors was analyzed using immunofluorescent staining or Proteome analysis. Changes in viability following exposure to gemcitabine and paclitaxel were measured using Live/Dead assay. Results PANC-1 cells formed 3D Tumor spheroids within 5 days and the number of spheroids increased when co-cultured with PSCs. Culture conditions were optimized for PANC-1 cells and PSCs, and their appropriate interaction was confirmed by reciprocal activation shown as increased cell motility. PSCs under co-culture showed an increased expression of α-SMA. Expression of EMT-related markers, such as vimentin and TGF-β, was higher in co-cultured PANC-1 spheroids compared to that in mono-cultured spheroids; as was the expression of many other EMT-related factors including TIMP1 and IL-8. Following gemcitabine exposure, no significant changes in survival were observed. When paclitaxel was combined with gemcitabine, a growth inhibitory advantage was prominent in Tumor spheroids, which was accompanied by significant cytotoxicity in PSCs. Conclusions We demonstrated that cancer cells grown as Tumor spheroids in a 3D collagen matrix and PSCs co-cultured in sub-millimeter proximity participate in mutual interactions that induce EMT and drug resistance in a microchannel plate. Microfluidic co-culture of Pancreatic Tumor spheroids with PSCs may serve as a useful model for studying EMT and drug resistance in a clinically relevant manner
Kevin L Bennewith - One of the best experts on this subject based on the ideXlab platform.
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the role of Tumor cell derived connective tissue growth factor ctgf ccn2 in Pancreatic Tumor growth
Cancer Research, 2009Co-Authors: Kevin L Bennewith, Xin Huang, Edward E Graves, Janine T Erler, Neeraja Kambham, Jonathan Feazell, George P Yang, Albert C Koong, Amato J GiacciaAbstract:Pancreatic cancer is highly aggressive and refractory to existing therapies. Connective tissue growth factor ( CTGF/CCN2 ) is a fibrosis-related gene that is thought to play a role in Pancreatic Tumor progression. However, CCN2 can be expressed in a variety of cell types, and the contribution of CCN2 derived from either Tumor cells or stromal cells as it affects the growth of Pancreatic Tumors is unknown. Using genetic inhibition of CCN2, we have discovered that CCN2 derived from Tumor cells is a critical regulator of Pancreatic Tumor growth. Pancreatic Tumor cells derived from CCN2 shRNA–expressing clones showed dramatically reduced growth in soft agar and when implanted s.c. We also observed a role for CCN2 in the growth of Pancreatic Tumors implanted orthotopically, with Tumor volume measurements obtained by positron emission tomography imaging. Mechanistically, CCN2 protects cells from hypoxia-mediated apoptosis, providing an in vivo selection for Tumor cells that express high levels of CCN2. We found that CCN2 expression and secretion was increased in hypoxic Pancreatic Tumor cells in vitro , and we observed colocalization of CCN2 and hypoxia in Pancreatic Tumor xenografts and clinical Pancreatic adenocarcinomas. Furthermore, we found increased CCN2 staining in clinical Pancreatic Tumor tissue relative to stromal cells surrounding the Tumor, supporting our assertion that Tumor cell–derived CCN2 is important for Pancreatic Tumor growth. Taken together, these data improve our understanding of the mechanisms responsible for Pancreatic Tumor growth and progression, and also indicate that CCN2 produced by Tumor cells represents a viable therapeutic target for the treatment of Pancreatic cancer. [Cancer Res 2009;69(3):775–84]
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The Role of Tumor Cell-Derived Connective Tissue Growth Factor (CTGF/CCN2) in Pancreatic Tumor Growth
Cancer research, 2009Co-Authors: Kevin L Bennewith, Xin Huang, Edward E Graves, Janine T Erler, Neeraja Kambham, Jonathan Feazell, George P Yang, Albert C Koong, Christine M. Ham, Amato J GiacciaAbstract:Pancreatic cancer is highly aggressive and refractory to existing therapies. Connective tissue growth factor ( CTGF/CCN2 ) is a fibrosis-related gene that is thought to play a role in Pancreatic Tumor progression. However, CCN2 can be expressed in a variety of cell types, and the contribution of CCN2 derived from either Tumor cells or stromal cells as it affects the growth of Pancreatic Tumors is unknown. Using genetic inhibition of CCN2, we have discovered that CCN2 derived from Tumor cells is a critical regulator of Pancreatic Tumor growth. Pancreatic Tumor cells derived from CCN2 shRNA–expressing clones showed dramatically reduced growth in soft agar and when implanted s.c. We also observed a role for CCN2 in the growth of Pancreatic Tumors implanted orthotopically, with Tumor volume measurements obtained by positron emission tomography imaging. Mechanistically, CCN2 protects cells from hypoxia-mediated apoptosis, providing an in vivo selection for Tumor cells that express high levels of CCN2. We found that CCN2 expression and secretion was increased in hypoxic Pancreatic Tumor cells in vitro , and we observed colocalization of CCN2 and hypoxia in Pancreatic Tumor xenografts and clinical Pancreatic adenocarcinomas. Furthermore, we found increased CCN2 staining in clinical Pancreatic Tumor tissue relative to stromal cells surrounding the Tumor, supporting our assertion that Tumor cell–derived CCN2 is important for Pancreatic Tumor growth. Taken together, these data improve our understanding of the mechanisms responsible for Pancreatic Tumor growth and progression, and also indicate that CCN2 produced by Tumor cells represents a viable therapeutic target for the treatment of Pancreatic cancer. [Cancer Res 2009;69(3):775–84]
Sanjay K Srivastava - One of the best experts on this subject based on the ideXlab platform.
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benzyl isothiocyanate suppresses Pancreatic Tumor angiogenesis and invasion by inhibiting hif α vegf rho gtpases pivotal role of stat 3
PLOS ONE, 2011Co-Authors: Srinivas Reddy Boreddy, Ravi P Sahu, Sanjay K SrivastavaAbstract:Our previous studies have shown that benzyl isothiocyanate (BITC) suppresses Pancreatic Tumor growth by inhibiting STAT-3; however, the exact mechanism of Tumor growth suppression was not clear. Here we evaluated the effects and mechanism of BITC on Pancreatic Tumor angiogenesis. Our results reveal that BITC significantly inhibits neovasularization on rat aorta and Chicken-Chorioallantoic membrane. Furthermore, BITC blocks the migration and invasion of BxPC-3 and PanC-1 Pancreatic cancer cells in a dose dependant manner. Moreover, secretion of VEGF and MMP-2 in normoxic and hypoxic BxPC-3 and PanC-1 cells was significantly suppressed by BITC. Both VEGF and MMP-2 play a critical role in angiogenesis and metastasis. Our results reveal that BITC significantly suppresses the phosphorylation of VEGFR-2 (Tyr-1175), and expression of HIF-α. Rho-GTPases, which are regulated by VEGF play a crucial role in Pancreatic cancer progression. BITC treatment reduced the expression of RhoC whereas up-regulated the expression of Tumor suppressor RhoB. STAT-3 over-expression or IL-6 treatment significantly induced HIF-1α and VEGF expression; however, BITC substantially suppressed STAT-3 as well as STAT-3-induced HIF-1α and VEGF expression. Finally, in vivo Tumor growth and matrigel-plug assay show reduced Tumor growth and substantial reduction of hemoglobin content in the matrigel plugs and Tumors of mice treated orally with 12 µmol BITC, indicating reduced Tumor angiogenesis. Immunoblotting of BITC treated Tumors show reduced expression of STAT-3 phosphorylation (Tyr-705), HIF-α, VEGFR-2, VEGF, MMP-2, CD31 and RhoC. Taken together, our results suggest that BITC suppresses Pancreatic Tumor growth by inhibiting Tumor angiogenesis through STAT-3-dependant pathway.
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Pancreatic Tumor suppression by benzyl isothiocyanate is associated with inhibition of pi3k akt foxo pathway
Clinical Cancer Research, 2011Co-Authors: Srinivas Reddy Boreddy, Kartick C Pramanik, Sanjay K SrivastavaAbstract:Purpose: Our previous studies have shown that benzyl isothiocyanate (BITC) suppress Pancreatic cancer growth by inducing apoptosis but the molecular mechanism was unclear. In this study we hypothesized the involvement of PI3K/AKT/FOXO pathway in BITC-induced apoptosis. Experimental Design: Mice were implanted BxPC-3 Tumor xenografts and orally gavaged with 12 μmol BITC. Plasma and Tumor BITC concentration was estimated by liquid chromatography/tandem mass spectrometry. BxPC-3 and PanC-1 cells were used to elucidate PI3K/AKT/FOXO pathway. Electrophoretic mobility shift assay (EMSA), DNA binding activity, immunofluorescence, and gene transfection were used to delineate the mechanism. Results: BITC-treated mice showed 43% less Tumor growth as compared with control mice and correlated well with the therapeutic concentrations of 6.5 μmol/L BITC achieved in plasma and 7.5 μmol/g BITC in Tumor tissue. Western blot analyses and immunohistochemistry revealed that Tumors from BITC-treated mice showed reduced phosphorylation of PI3K, AKT, PDK1, mTOR, FOXO1, and FOXO3a and increased apoptosis. Complementing our in vivo results, we made similar observations in a dose- and time-dependent manner in BITC-treated BxPC-3 and Panc-1 cells. Binding of FOXO1 with 14-3-3 proteins was also reduced drastically by BITC treatment indicating nuclear retention of FOXO1 and this observation was further confirmed with EMSA, immunofluorescence, DNA binding, and upregulation of FOXO-responsive proteins Bim, p27, and p21 in BxPC-3 cells. Overexpression of AKT by transient transfection significantly blocked the modulation of FOXO proteins and protected the cells from BITC-mediated apoptosis and growth suppression. Conclusions: Our results provide convincing evidence on the involvement of PI3K/AKT/FOXO pathway in BITC-mediated Pancreatic Tumor growth suppression. Clin Cancer Res; 17(7); 1784–95. ©2011 AACR .
