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T1164 Increased Longevity in Polyp-Bearing Mice Treated With Piroxicam
AGA Abstracts
the expression levels of the major pro- and anti-apoptotic Bcl-2 proteins, as well as p53 and k-ras status, in a panel of human colon cancer cell lines (DLD-1, LoVo, Colo205, HT29, HCT116, HCT116 p53-/- & HCT116 PUMA-/-) and patient tumour samples (n=24) using Western blotting techniques. In parallel, we assessed the sensitivity of these cell lines to treatment with 5-FU and oxaliplatin, in the presence and absence of BH3 mimetics. This was performed using Annexin V / Propidium Iodide staining and subsequent flow cytometry analysis to assess apoptosis induction by these treatments. RESULTS: Western blotting demonstrated high expression levels of Bcl-2 family proteins in colon cancer cell lines, with varying expression levels in individual patient tumour samples and matched normal tissue. BH3 mimetics sensitised all cell lines to 5-FU and oxaliplatin treatment, with significantly enhanced apoptosis relative to combination treatment of 5-FU and oxaliplatin alone (p<0.05). This sensitisation occurred independently of either p53 or k-ras status. BH3 mimetics also induced apoptosis when used as a single agent over longer time periods (p<0.05). CONCLUSIONS: The Bcl-2 family of proteins are highly expressed in colon cancer, with expression varying between cell lines, and between patient tumour samples and matched normal tissue. BH3 mimetics, which target the apoptotic pathway, can sensitise cell lines to 5-FU and oxaliplatin treatment and warrant further investigation as potential adjuvant therapies for the treatment of colorectal cancer.
polyp, and others. A follow-up survey was carried out by calling the patients directly, or sending questionnaires to the hospitals where patients were followed, to request the information about survival and recurrence. Kaplan-Meier method was used to analyze long-term outcomes. Results: 45 patients with 51 duodenal adenomas and intramucosal adenocarcinomas were evaluated. Median age of patients was 59 years (33-79) and male were 31. 51 lesions consisted of 29 tubular adenomas, 21 well differentiated adenocarcinomas, and one poorly differentiated adenocarcinoma. Mean size of lesions was 11.4mm (Median 10mm, Range 3-40mm). Shape of lesions were 15 protruded type (29%), 29 flat elevated type (57%), and seven depressed type (14%). Tumors were removed by nine snarectomies (18%), 35 strip methods with 2-channel endoscope (69%), or seven endoscopic submucosal dissections (ESD) (14%). Complete en bloc resection rate was 80.4%. Local recurrence rate was 5.4% and lymph node recurrence rate was 0% (Median follow-up period was 26 (1193) and 61.5 (9-193) months, respectively). 5- and 10-years overall survival rate of 41 patients (91.1%) followed after ER was 92.8% and 84.4%, respectively. 10-years disease specific survival was 100% (Median follow-up period was 56 months (6-193)). 1- and 3years disease free survival of 37 patients followed by EGD was 97.3% and 93.7%, respectively (Median follow-up period of 26 months (1-193)). Five late bleedings (9.8%), four perforations (7.8%), and three retroperitoneal abscesses (5.9%) were seen after ER. All patients encountered complication were recovered nonsurgically. Conclusion: ER was a feasible treatment for duodenal adenomas and intramucosal carcinomas from a point of long-term prognosis. However, serious complications including retroperitoneal abscess can occur, therefore sufficient informed consent should be needed.
T1162 Analysis of Antiproliferative and Chemosensitizing Effects of Sunitinib on Human Esophagogastric Cancer Cells: Synergistic Interaction With Vandetanib via Inhibition of Multireceptor Tyrosine Kinase Pathways Orestis Lyros, Annett Mueller, Florian Heidel, Carl Christoph Schimanski, Ines Gockel, Peter R. Galle, Hauke Lang, Markus Moehler
T1164 Increased Longevity in Polyp-Bearing Mice Treated With Piroxicam Karen M. McCartney, Chris J. Hawkey, Andrew J. Bennett
The receptor tyrosine kinases (RTKs) , epidermal growth factor receptor (EGFR) and vascular endothelial growth factor receptor 1-3 (VEGFR1-3), are frequently expressed in gastric cancer and are putative therapeutic targets in this disease. We have investigated the anti-proliferative and chemosensitizing properties of the multi-targeted small-molecule RTK inhibitors sunitinib and vandetanib in a panel of four human gastric & esophageal cancer cell lines(AGS, MKN-45, NCI-N87, OE33). In the first instance, the expression of potential targets of these small-molecule inhibitors was examined by reverse transcriptase-polymerase chain reaction, western blotting and flow cytometry. EGFR mRNA and protein was detected in all cases, with VEGFR2 expression noted in all but one line. Both EGF and VEGF were shown to stimulate tumor cell growth, and both sunitinib and vandetanib were found to be associated with significant dose-dependent inhibition of proliferation and an enhancement of apoptosis, as determined by MTT and propidium iodide/Annexin V labeling assays, respectively. The addition of sunitinib to VEGF-stimulated NCI-N87 cells was associated with a reduction in MAPK phosphorylation (pMAPK) but not Akt phosphorylation (pAkt), whereas the addition of vandetanib was associated with reductions in both VEGF- and EGF-mediated VEGFR2 phosphorylation, pMAPK and pAkt. Co-administration of sunitinib significantly enhanced the sensitivity of MKN-45 cells to cisplatin and irinotecan. In addition, vandetanib synergistically enhanced the sunitinib-associated inhibition of gastric cancer cell growth. In conclusion, these preliminary data confirm the importance of EGFR and VEGFR signaling in gastric cancer and suggest that the simultaneous inhibition of RTK-pathways through sunitinib and vandetanib may provide therapeutic benefit in this disease.
INTRODUCTION Non-steroidal anti-inflammatory drugs (NSAIDs) have shown to have chemopreventative properties against the development of colonic polyps and cancers. We have previously shown that Peroxisome Proliferator Activated Receptor (PPAR)-alpha also acts to constrain poly development in APC min+/- mice. Because both eicosanoids and NSAIDs are ligands for PPAR-alpha we investigated the hypothesis that the effects of NSAIDs might be mediated through activation of PPAR-alpha. METHODS A colony of PPAR-/- null mice on a C57 background was developed and bred to homogeneity before crossing with C57 black APC min+/- mice. Piroxicam 100 parts per million (ppm) was added to the drinking water of half the mice, and the effect of genotype and treatment on longevity, mouse phenotype and small and large intestinal polyp number were investigated. Mice were killed if they showed signs of white paw or tumour prolapse or at 1 year if they remained healthy, and the small and large intestines and the mesenteric fat removed separately. RESULTS Age at death was 23.1 (median, interquartile range17.9-25.6) weeks in APC min+/mice not treated with piroxicam (n=27) vs 19.3 (17.4-25.0, maximum 34.9) weeks in PPAR knockout mice (n=31). Unexpectedly, longevity was increased substantially, with piroxicam treatment in both PPAR knockouts to 49.2 (32.8-52.1) weeks with 8 of 16 culled at one year and in APC min+/- to 52.9 (51.6-55.1) weeks, with 9 of 10 culled at one year). There was more mesenteric fat in APC min+/- mice treated with piroxicam: 0.96 (0.65-1.36)g vs 0.14 (0.06-0.22)g. In APC min+/- mice values were 0.31 (0.19-0.95)g vs 0.23 (0.12-0.28)g. In an as yet uncompleted analysis mice treated with piroxicam appeared to have fewer, though often large, polyps. Fuller data will be available at the time of presentation. CONCLUSIONS Piroxicam 100ppm in drinking water results in substantial prolongation of life, to an age greater than previously reported for min mice. The effect may be by PPAR-alpha independent mechanisms and associated with a reduction in polyp development. Piroxicam could be considered as therapy for patients at increased risk. T1165 Use of Newer Agents in the Treatment of Gastric Adenocarcinoma Kaumudi Somnay, Sandeep Kumar, Leonard P. James, Barry H. Kaplan BACKGROUND: Gastric cancer is the second most common cause of cancer-related deaths world-wide. Standard treatment of advanced stage gastric adenocarcinoma has evolved into a 3 drug regimen consisting of Docetaxel, Cisplatin and 5-Fluorouracil (5-FU), and generally has a median survival of 9 months. INTRODUCTION: The standard regimen's toxicities can affect patient compliance and thus overall results. We hypothesized that substituting other FDA-approved chemotherapeutic agents for the standard drugs would result in better tolerability with similar or improved efficacy. METHODS: A retrospective chart review was performed for all patients in an outpatient setting diagnosed with gastric/GE junction carcinoma. These patients had been offered the standard treatment and an option to try a potentially more tolerable regimen using Carboplatin in place of Cisplatin and Paclitaxel in place of Docetaxel and/or Capecitabine in place of 5-FU. 24 patients were assessed during 2005 to 2009. Patients were classified according to the regimen chosen: Paclitaxel, Carboplatin, Capecitabine (PCC); Paclitaxel, Carboplatin, 5-FU (PCF); or Docetaxel, Carboplatin, Capecitabine (DCC). For all three regimens, compliance, toxicity and survival length were noted. RESULTS: 17 were treated with PCC, 3 with PCF, and 4 with DCC. Stages ranged from IB to IV. Average CTCAE 3.0 hematologic toxicity was grade 1 for anemia, neutropenia, and thrombocytopenia, which is comparable to the standard regimen. Two patients experienced grade 3/4 thrombocytopenia (PCC group); grade 3 neutropenias noted for PCC (2) and PCF (1). Mean survival for all patients (both adjuvant and unresectable) was 22.2 months on PCC, 6.4 months on PCF, and 19.7 months on DCC. For PCF and DCC, the survival data was longer than other studies, possibly due to the low numbers of patients evaluated. PCC appeared to have the best survival, though only 17 patients were studied. CONCLUSION: Our data suggests that treatment with PCC may increase survival length with comparable toxicity to the standard treatment. A formal clinical trial is in preparation to explore this regimen in a larger population. Hematologic Toxicity
T1163 Efficacy, Safety, and Long-Term Outcomes of Endoscopic Resection of Nonampullary Duodenal Adenomas and Intramucosal Carcinomas Takuya Inoue, Noriya Uedo, Ryu Ishihara, Yoji Takeuchi, Koji Higashino, Hiroyasu Iishi, Masaharu Tatsuta Background and Aims: Endoscopic resection (ER) is an effective treatment for early duodenal neoplasms because they rarely cause lymph node metastasis. However, long-term outcomes of duodenal adenomas and intramucosal carcinomas after ER were unclear. The aims of this study were to evaluate the efficacy, safety, and long-term outcomes of ER for nonampurally duodenal adenomas and intramucosal carcinomas. Methods: 61 patients with 73 duodenal lesions treated by ER in our hospital between January 1993 and October 2009 were picked up from database. To evaluate the efficacy of ER for nonampurally duodenal adenomas and adenocarcinomas, patients were excluded if they were histopathologically diagnosed as carcinoid, gastrointestinal stromal tumor (GIST), Brunner gland's hyperplasia, hyperplastic
AGA Abstracts
S-502
the expression levels of the major pro- and anti-apoptotic Bcl-2 proteins, as well as p53 and k-ras status, in a panel of human colon cancer cell lines (DLD-1, LoVo, Colo205, HT29, HCT116, HCT116 p53-/- & HCT116 PUMA-/-) and patient tumour samples (n=24) using Western blotting techniques. In parallel, we assessed the sensitivity of these cell lines to treatment with 5-FU and oxaliplatin, in the presence and absence of BH3 mimetics. This was performed using Annexin V / Propidium Iodide staining and subsequent flow cytometry analysis to assess apoptosis induction by these treatments. RESULTS: Western blotting demonstrated high expression levels of Bcl-2 family proteins in colon cancer cell lines, with varying expression levels in individual patient tumour samples and matched normal tissue. BH3 mimetics sensitised all cell lines to 5-FU and oxaliplatin treatment, with significantly enhanced apoptosis relative to combination treatment of 5-FU and oxaliplatin alone (p<0.05). This sensitisation occurred independently of either p53 or k-ras status. BH3 mimetics also induced apoptosis when used as a single agent over longer time periods (p<0.05). CONCLUSIONS: The Bcl-2 family of proteins are highly expressed in colon cancer, with expression varying between cell lines, and between patient tumour samples and matched normal tissue. BH3 mimetics, which target the apoptotic pathway, can sensitise cell lines to 5-FU and oxaliplatin treatment and warrant further investigation as potential adjuvant therapies for the treatment of colorectal cancer.
polyp, and others. A follow-up survey was carried out by calling the patients directly, or sending questionnaires to the hospitals where patients were followed, to request the information about survival and recurrence. Kaplan-Meier method was used to analyze long-term outcomes. Results: 45 patients with 51 duodenal adenomas and intramucosal adenocarcinomas were evaluated. Median age of patients was 59 years (33-79) and male were 31. 51 lesions consisted of 29 tubular adenomas, 21 well differentiated adenocarcinomas, and one poorly differentiated adenocarcinoma. Mean size of lesions was 11.4mm (Median 10mm, Range 3-40mm). Shape of lesions were 15 protruded type (29%), 29 flat elevated type (57%), and seven depressed type (14%). Tumors were removed by nine snarectomies (18%), 35 strip methods with 2-channel endoscope (69%), or seven endoscopic submucosal dissections (ESD) (14%). Complete en bloc resection rate was 80.4%. Local recurrence rate was 5.4% and lymph node recurrence rate was 0% (Median follow-up period was 26 (1193) and 61.5 (9-193) months, respectively). 5- and 10-years overall survival rate of 41 patients (91.1%) followed after ER was 92.8% and 84.4%, respectively. 10-years disease specific survival was 100% (Median follow-up period was 56 months (6-193)). 1- and 3years disease free survival of 37 patients followed by EGD was 97.3% and 93.7%, respectively (Median follow-up period of 26 months (1-193)). Five late bleedings (9.8%), four perforations (7.8%), and three retroperitoneal abscesses (5.9%) were seen after ER. All patients encountered complication were recovered nonsurgically. Conclusion: ER was a feasible treatment for duodenal adenomas and intramucosal carcinomas from a point of long-term prognosis. However, serious complications including retroperitoneal abscess can occur, therefore sufficient informed consent should be needed.
T1162 Analysis of Antiproliferative and Chemosensitizing Effects of Sunitinib on Human Esophagogastric Cancer Cells: Synergistic Interaction With Vandetanib via Inhibition of Multireceptor Tyrosine Kinase Pathways Orestis Lyros, Annett Mueller, Florian Heidel, Carl Christoph Schimanski, Ines Gockel, Peter R. Galle, Hauke Lang, Markus Moehler
T1164 Increased Longevity in Polyp-Bearing Mice Treated With Piroxicam Karen M. McCartney, Chris J. Hawkey, Andrew J. Bennett
The receptor tyrosine kinases (RTKs) , epidermal growth factor receptor (EGFR) and vascular endothelial growth factor receptor 1-3 (VEGFR1-3), are frequently expressed in gastric cancer and are putative therapeutic targets in this disease. We have investigated the anti-proliferative and chemosensitizing properties of the multi-targeted small-molecule RTK inhibitors sunitinib and vandetanib in a panel of four human gastric & esophageal cancer cell lines(AGS, MKN-45, NCI-N87, OE33). In the first instance, the expression of potential targets of these small-molecule inhibitors was examined by reverse transcriptase-polymerase chain reaction, western blotting and flow cytometry. EGFR mRNA and protein was detected in all cases, with VEGFR2 expression noted in all but one line. Both EGF and VEGF were shown to stimulate tumor cell growth, and both sunitinib and vandetanib were found to be associated with significant dose-dependent inhibition of proliferation and an enhancement of apoptosis, as determined by MTT and propidium iodide/Annexin V labeling assays, respectively. The addition of sunitinib to VEGF-stimulated NCI-N87 cells was associated with a reduction in MAPK phosphorylation (pMAPK) but not Akt phosphorylation (pAkt), whereas the addition of vandetanib was associated with reductions in both VEGF- and EGF-mediated VEGFR2 phosphorylation, pMAPK and pAkt. Co-administration of sunitinib significantly enhanced the sensitivity of MKN-45 cells to cisplatin and irinotecan. In addition, vandetanib synergistically enhanced the sunitinib-associated inhibition of gastric cancer cell growth. In conclusion, these preliminary data confirm the importance of EGFR and VEGFR signaling in gastric cancer and suggest that the simultaneous inhibition of RTK-pathways through sunitinib and vandetanib may provide therapeutic benefit in this disease.
INTRODUCTION Non-steroidal anti-inflammatory drugs (NSAIDs) have shown to have chemopreventative properties against the development of colonic polyps and cancers. We have previously shown that Peroxisome Proliferator Activated Receptor (PPAR)-alpha also acts to constrain poly development in APC min+/- mice. Because both eicosanoids and NSAIDs are ligands for PPAR-alpha we investigated the hypothesis that the effects of NSAIDs might be mediated through activation of PPAR-alpha. METHODS A colony of PPAR-/- null mice on a C57 background was developed and bred to homogeneity before crossing with C57 black APC min+/- mice. Piroxicam 100 parts per million (ppm) was added to the drinking water of half the mice, and the effect of genotype and treatment on longevity, mouse phenotype and small and large intestinal polyp number were investigated. Mice were killed if they showed signs of white paw or tumour prolapse or at 1 year if they remained healthy, and the small and large intestines and the mesenteric fat removed separately. RESULTS Age at death was 23.1 (median, interquartile range17.9-25.6) weeks in APC min+/mice not treated with piroxicam (n=27) vs 19.3 (17.4-25.0, maximum 34.9) weeks in PPAR knockout mice (n=31). Unexpectedly, longevity was increased substantially, with piroxicam treatment in both PPAR knockouts to 49.2 (32.8-52.1) weeks with 8 of 16 culled at one year and in APC min+/- to 52.9 (51.6-55.1) weeks, with 9 of 10 culled at one year). There was more mesenteric fat in APC min+/- mice treated with piroxicam: 0.96 (0.65-1.36)g vs 0.14 (0.06-0.22)g. In APC min+/- mice values were 0.31 (0.19-0.95)g vs 0.23 (0.12-0.28)g. In an as yet uncompleted analysis mice treated with piroxicam appeared to have fewer, though often large, polyps. Fuller data will be available at the time of presentation. CONCLUSIONS Piroxicam 100ppm in drinking water results in substantial prolongation of life, to an age greater than previously reported for min mice. The effect may be by PPAR-alpha independent mechanisms and associated with a reduction in polyp development. Piroxicam could be considered as therapy for patients at increased risk. T1165 Use of Newer Agents in the Treatment of Gastric Adenocarcinoma Kaumudi Somnay, Sandeep Kumar, Leonard P. James, Barry H. Kaplan BACKGROUND: Gastric cancer is the second most common cause of cancer-related deaths world-wide. Standard treatment of advanced stage gastric adenocarcinoma has evolved into a 3 drug regimen consisting of Docetaxel, Cisplatin and 5-Fluorouracil (5-FU), and generally has a median survival of 9 months. INTRODUCTION: The standard regimen's toxicities can affect patient compliance and thus overall results. We hypothesized that substituting other FDA-approved chemotherapeutic agents for the standard drugs would result in better tolerability with similar or improved efficacy. METHODS: A retrospective chart review was performed for all patients in an outpatient setting diagnosed with gastric/GE junction carcinoma. These patients had been offered the standard treatment and an option to try a potentially more tolerable regimen using Carboplatin in place of Cisplatin and Paclitaxel in place of Docetaxel and/or Capecitabine in place of 5-FU. 24 patients were assessed during 2005 to 2009. Patients were classified according to the regimen chosen: Paclitaxel, Carboplatin, Capecitabine (PCC); Paclitaxel, Carboplatin, 5-FU (PCF); or Docetaxel, Carboplatin, Capecitabine (DCC). For all three regimens, compliance, toxicity and survival length were noted. RESULTS: 17 were treated with PCC, 3 with PCF, and 4 with DCC. Stages ranged from IB to IV. Average CTCAE 3.0 hematologic toxicity was grade 1 for anemia, neutropenia, and thrombocytopenia, which is comparable to the standard regimen. Two patients experienced grade 3/4 thrombocytopenia (PCC group); grade 3 neutropenias noted for PCC (2) and PCF (1). Mean survival for all patients (both adjuvant and unresectable) was 22.2 months on PCC, 6.4 months on PCF, and 19.7 months on DCC. For PCF and DCC, the survival data was longer than other studies, possibly due to the low numbers of patients evaluated. PCC appeared to have the best survival, though only 17 patients were studied. CONCLUSION: Our data suggests that treatment with PCC may increase survival length with comparable toxicity to the standard treatment. A formal clinical trial is in preparation to explore this regimen in a larger population. Hematologic Toxicity
T1163 Efficacy, Safety, and Long-Term Outcomes of Endoscopic Resection of Nonampullary Duodenal Adenomas and Intramucosal Carcinomas Takuya Inoue, Noriya Uedo, Ryu Ishihara, Yoji Takeuchi, Koji Higashino, Hiroyasu Iishi, Masaharu Tatsuta Background and Aims: Endoscopic resection (ER) is an effective treatment for early duodenal neoplasms because they rarely cause lymph node metastasis. However, long-term outcomes of duodenal adenomas and intramucosal carcinomas after ER were unclear. The aims of this study were to evaluate the efficacy, safety, and long-term outcomes of ER for nonampurally duodenal adenomas and intramucosal carcinomas. Methods: 61 patients with 73 duodenal lesions treated by ER in our hospital between January 1993 and October 2009 were picked up from database. To evaluate the efficacy of ER for nonampurally duodenal adenomas and adenocarcinomas, patients were excluded if they were histopathologically diagnosed as carcinoid, gastrointestinal stromal tumor (GIST), Brunner gland's hyperplasia, hyperplastic
AGA Abstracts
S-502