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.

Background: Success of chemotherapy and alleviation of pain are frequently less than optimal in pancreatic cancer patients, leading to increasing interest in new pharmacological substances, such as vanilloids. Our study addressed the question of whether vanilloids influence pancreatic cancer cell growth, and if vanilloids could be used for pain treatment via the vanilloid 1 receptor (VR1) in pancreatic cancer patients. Methods: In vitro, the effect of resiniferatoxin (vanilloid analogue) on apoptosis and cell growth in pancreatic cancer cells-either alone, combined with 5-fluorouracil (5-FU), or combined with gemcitabine-was determined by annexin V staining, FACS analysis, and MTT assay, respectively. VR1 expression was evaluated on RNA and protein level by quantitative polymerase chain reaction and immunohistochemistry in human pancreatic cancer and chronic pancreatitis. Patient characteristicsespecially pain levels-were registered in a prospective database and correlated with VR1 expression. Results: Resiniferatoxin induced apoptosis by targeting mitochondrial respiration and decreased cell growth in pancreatic cancer cells without showing synergistic effects with 5-FU or gemcitabine. Expression of VR1 was significantly upregulated in human pancreatic cancer and chronic pancreatitis. VR1 expression was related to the intensity of pain reported by cancer patients but not to the intensity of pain reported by patients with chronic pancreatitis. Conclusions: Resiniferatoxin induced apoptosis in pancreatic cancer cells indicates that vanilloids may be useful in the treatment of human pancreatic cancer. Furthermore, vanilloid might be a novel and effective treatment option for neurogenic pain in patients with pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive malignancies, with an overall 5-year survival rate of less than 5%. Invasive tumor growth and early metastasis are two important reasons for this dismal prognosis. Osteopontin (OPN) is a secretory protein with a variety of functions, for example in cell adhesion and migration, inflammatory reaction and apoptosis. In this study the functional role of OPN in human pancreatic cancer and its potential use as a disease marker were analyzed. By real time quantitative PCR, there was a 2.2-fold and 1.6-fold increase of OPN mRNA in pancreatic cancers (n = 23) and chronic pancreatitis samples (n = 22), respectively, compared to normal pancreatic tissues (n = 20). Immunohistochemical analysis demonstrated OPN staining in 60% of the primary pancreatic tumors and in 72% of the lymph node and liver metastases. ELISA analysis of serum samples obtained from pancreatic cancer patients (n = 70), chronic pancreatitis patients (n = 12), and healthy donors (n = 20) showed a 1.6-fold increase in OPN serum levels in patients with tumors and a 1.9-fold increase in patients with chronic pancreatitis. Recombinant human OPN significantly increased the invasiveness of pancreatic cancer cells, without having any impact on cell proliferation. In addition, down regulation of OPN by specific siRNA molecules decreased pancreatic cancer cell invasion. In conclusion, OPN serum levels in pancreatic cancer and chronic pancreatitis patients are not significantly different, thereby restricting its role as a prognostic or follow-up marker. Our results do suggest, however, that blockade of OPN might be useful as a therapeutic approach to inhibit invasion and metastasis of pancreatic cancer cells.

Decorin is a molecular marker of desmoplasia in CP, and excessive decorin may allow fibrotic masses to nourish and protract inflammation by deregulating the process of MNC accumulation and activation. These data provide a molecular basis for surgical resection of diseased tissue as a treatment option in CP.

BACKGROUND: Pancreatic cancer is 1 of the most common and poorly treated tumors. In search of new therapeutic approaches, the oxygen sensors prolyl hydroxylases (PHD) are potential targets. PHD2 is considered the key oxygen sensor-regulating hypoxia-inducible factor (HIF). Currently, there is conflicting evidence regarding the exact role of PHD2 in tumorigenesis. The objective of this study was to investigate the role of PHD2 in pancreatic cancer growth and progression. METHODS: PHD2 expression was analyzed by quantitative real-time polymerase chain reaction analysis and immunohistochemistry in human tissue specimens and cell lines. Knockdown of PHD2 was done by using short-interfering RNAs (siRNAs) specific against PHD2, and PHD2 overexpression was achieved by stable combinational DNA transfection. In vivo, an orthotopic murine model was used. Angiogenic cytokines were assessed with enzyme-linked immunosorbent assays, and invasion was studied with Matrigel assays. RESULTS: PHD2 expression was not altered substantially in cancer tissues and their metastases. Lymph node-negative tissues had higher levels of PHD2 than lymph node-positive tissues. PHD2 was hypoxia-inducible in pancreatic cancer cell lines and regulated cell growth through cyclin D1 down-regulation samples with PHD2 suppression and through p21 up-regulation in samples with of PHD2 overexpression. In vivo, PHD2 caused tumor growth retardation and reduced tumor invasion by inhibiting angiogenesis. This observation was caused by the suppression of angiogenic cytokines and tumor invasion. CONCLU-SIONS: The current results indicated that PHD2 plays an important role in pancreatic tumorigenesis. In summary, the authors concluded that PHD2 may function as a tumor suppressor gene in pancreatic cancer and, thus, may define a potential target for the treatment of pancreatic cancer. Cancer 2012;118:960-