Altered expression of apoptosis-regulating genes plays an important role in the aggressive growth behavior and chemoresistance of pancreatic ductal adenocarcinoma. In the present study, the hypoxia-inducible proapoptotic gene, BNIP3, was analysed in terms of expression, effect on patient survival, and chemo-responsiveness in pancreatic cancer cell lines. cDNA microarray, real-time light cycler s quantitative polymerase chain reaction, laser-capture microdissection, and immunohistochemistry analyses were used to evaluate BNIP3 expression in normal and diseased pancreatic specimens. Modulation of BNIP3 expression was achieved using specific siRNA molecules. The effect of chemotherapeutic agents on pancreatic cancer cells was assessed utilizing 3-(4,5-methylthiazol-2-yl)-2,5-diphenyltetrazolium-bromide assays. BNIP3 mRNA levels were 3.0-and 6.3-fold lower in chronic pancreatitis and pancreatic cancer compared to the normal pancreas, respectively. Microdissection analysis confirmed the reduction of BNIP3 expression in pancreatic cancer cells compared to normal duct cells. By immunohistochemistry, BNIP3 was predominantly expressed in the acinar cells of the normal and diseased pancreas. Interestingly, while BNIP3 was undetectable in the cancer cells of 59% of the cases, 75-100% of PanIN2/3 lesions displayed BNIP3 immunoreactivity. Loss of BNIP3 expression correlated with poorer survival of patients (8 vs 14 months for BNIP3 negative vs positive tumors). Hypoxia induced BNIP3 expression in four out of eight pancreatic cancer cell lines, while it was absent under normoxic and hypoxic conditions in the remaining four. Downregulation of BNIP3 resulted in increased resistance to 5-fluoro-uracil and gemcitabine. In conclusion, loss of BNIP3 expression occurs late in pancreatic cancer, contributes to resistance to chemotherapy, and correlates with a worsened prognosis.
BackgroundDramatic weight loss is an often underestimated symptom in pancreatic cancer patients. Cachexia- defined as an unintended loss of stable weight exceeding 10% – is present in up to 80% of patients with cancer of the upper gastrointestinal tract, and has a significant influence on survival. The aim of the study was to show the multiple systemic effects of cachexia in pancreatic cancer patients, in terms of resection rate, effects on pulmonary function, amount of fat and muscle tissue, as well as changes in laboratory parameters.MethodsIn patients with pancreatic cancer, clinical appearance was documented, including the amount of weight loss. Laboratory parameters and lung-function tests were evaluated, and the thickness of muscle and fat tissue was measured with computed tomography scans. Statistical analysis, including multivariate analysis, was performed using SPSS software. Survival curves were calculated using Kaplan-Meier analysis and the log-rank test. To test for significant differences between the examined groups we used Student's t-test and the Mann-Whitney U test. Significance was defined as p < 0.05.ResultsOf 198 patients with a ductal adenocarcinoma of the pancreas, 70% were suffering from weight loss when they presented for operation, and in 40% weight loss exceeded 10% of the stable weight. In patients with cachexia, metastases were diagnosed significantly more often (47% vs. 24%, P < 0.001), leading to a significantly reduced resection rate in these patients. Patients with cachexia had significantly reduced fat tissue amounts. Hence, dramatic weight loss in a patient with pancreatic cancer may be a hint of a more progressed or more aggressive tumour.ConclusionPancreatic cancer patients with cachexia had a higher rate of more progressed tumour stages and a worse nutritional status. Furthermore, patients with cachexia had an impaired lung function and a reduction in fat tissue. Patients with pancreatic cancer and cachexia had significantly reduced survival. If weight loss exceeded 5% there was a significantly reduced resection rate to detect, but the changes were significantly more substantial if weight loss was 10% or more. We propose that a weight loss of 10% be defined as significant in pancreatic cancer.
The expression and localization of FXYD domain containing ion transport regulator 3 (FXYD3), a transmembrane protein that acts as a chloride channel or chloride channel regulator, was analyzed in pancreatic tissues derived from donors and patients suffering from chronic pancreatitis (CP) or pancreatic ductal adenocarcinoma (PDAC) as well as in pancreatic cancer cells using QRT-PCR, laser-capture microdissection and microarray analysis, in situ hybridization and immunohistochemistry. FXYD3 antisense expressing T3M4 pancreatic cancer cells were generated and compared to control cells using anchorage-dependent and independent growth assays, and xenotransplantation into nude mice. FXYD3 mRNA levels were 3.4-fold increased in PDAC tissues compared to donor specimens (p 5 0.006), and 3.9-fold increased in microdissected cancer cells compared to normal pancreatic ductal cells (p 5 0.02). FXYD3 was localized in the tubular complexes and PanIN lesions of both CP and PDAC, as well as in pancreatic cancer cells. Downregulation of FXYD3 by stable antisense transfection increased significantly the doubling time of T3M4 pancreatic cancer cells from 44 6 2 hr to 55 6 12 hr (p 5 0.02). Nude mice transplanted with antisense transfected cells displayed a significant increase in tumor doubling time from 3.3 days 6 1.0 to 4.3 days 6 0.43 (p 5 0.058). Anchorage-independent growth and sensitivity to 5-fluorouracil, gemcitabine and cisplatin as well as to MgCl 2 were not dependent on the level of FXYD3 expression. In conclusion, overexpression of FXYD3 in pancreatic cancer may contribute to the proliferative activity of this malignancy. ' 2005 Wiley-Liss, Inc.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.