angiogenin and Pancreatic-Neoplasms

Pancreatic ribonuclease (RNase) is a secreted enzyme critical for host defense. We discover an intrinsic RNase function, serving as a ligand for epidermal growth factor receptor (EGFR), a member of receptor tyrosine kinase (RTK), in pancreatic ductal adenocarcinoma (PDAC). The closely related bovine RNase A and human RNase 5 (angiogenin [ANG]) can trigger oncogenic transformation independently of their catalytic activities via direct association with EGFR. Notably, high plasma ANG level in PDAC patients is positively associated with response to EGFR inhibitor erlotinib treatment. These results identify a role of ANG as a serum biomarker that may be used to stratify patients for EGFR-targeted therapies, and offer insights into the ligand-receptor relationship between RNase and RTK families.

Topics: Animals; Binding Sites; Biomarkers; Carcinoma, Pancreatic Ductal; Cattle; Cell Line, Tumor; ErbB Receptors; Erlotinib Hydrochloride; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; HeLa Cells; Humans; Mice; Neoplasm Transplantation; Pancreatic Neoplasms; Ribonuclease, Pancreatic; Signal Transduction

Neamine, a non-toxic derivative of neomycin, has recently been shown to have antitumor activities in various types of cancers. However, its effect on pancreatic cancer is still unknown. The study aimed to investigate its antitumor activity on pancreatic cancer and the underlying mechanisms. MTT assay was used to observe the effect of neamine on angiogenin (ANG)-induced AsPC-1 cell proliferation. Tissue microassay and immunofluorescence staining were used to detect the expression of ANG and its nuclear translocation, respectively. Tumor xenografts were established by subcutaneous inoculation of AsPC-1 pancreatic cancer cells into the right flanks of nude mice, and neamine was injected subcutaneously. Immunohistochemistry was done to observe the expression of ANG, CD31 and Ki-67 in tumor xenografts. It was found that neamine blocked the nuclear translocation of ANG effectively and inhibited ANG-induced AsPC-1 cell proliferation in a dose-dependent manner. Neamine had anti-tumor effects on AsPC-1 xenograft models. Consistently, neamine reduced the expression levels of ANG, Ki-67 and CD31 in tumor xenografts. It was concluded that neamine may be a promising agent for treatment of pancreatic cancer.

Topics: Adult; Animals; Antibiotics, Antineoplastic; Carcinoma; Cell Line, Tumor; Cell Proliferation; Framycetin; Humans; Ki-67 Antigen; Male; Mice; Mice, Inbred BALB C; Mice, Nude; Middle Aged; Pancreatic Neoplasms; Platelet Endothelial Cell Adhesion Molecule-1; Ribonuclease, Pancreatic

Despite existing chemotherapy and surgical resection strategies, pancreatic cancer is one of the major causes of mortality in the United States with a 5-year mean survival rate of less than 5%. The activation of the urokinase-type plasminogen activator receptor-urokinase-type plasminogen activator (uPAR-uPA) system in the development of pancreatic ductal adenocarcinoma has been well established. In the present study, we used 2 pancreatic cancer cell lines, MIA PaCa-2 and PANC-1 to show the effects of uPAR and uPA downregulation. From the results, we observed that RNAi expressing plasmids efficiently downregulated mRNA and protein expression of uPAR and uPA. In vitro and in vivo angiogenic assays revealed a significant decrease in the angiogenic potential of MIA PaCa-2 and PANC-1 cells that were downregulated for both uPAR and uPA. From the angiogenesis antibody array analysis, we observed that the simultaneous downregulation of uPAR and uPA resulted in the downregulation of angiogenin and overexpression of RANTES. Further, FACS analysis showed that the simultaneous downregulation of uPAR and uPA caused the accumulation of cells in the sub-G(0/1) phase in both MIA PaCa-2 and PANC-1 cells. In addition, Western blot analysis revealed that downregulation of uPAR and uPA caused the activation of caspase 8 and CAD, which is indicative of apoptosis, and in vivo TUNEL assay confirmed these results. Finally, we observed the nuclear localization of uPA and that uPA interacts with the transcription factor Lhx-2. Taken together, the results of the present study show that the targeting of the uPAR-uPA system has therapeutic potential.

Topics: Animals; Apoptosis; Aspartate Carbamoyltransferase; Carbamoyl-Phosphate Synthase (Glutamine-Hydrolyzing); Carcinoma, Pancreatic Ductal; Caspase 8; Cell Line, Tumor; Chemokine CCL5; Dihydroorotase; Gene Targeting; Homeodomain Proteins; Humans; LIM-Homeodomain Proteins; Mice; Neoplasm Invasiveness; Neovascularization, Pathologic; Pancreatic Neoplasms; Receptors, Urokinase Plasminogen Activator; Ribonuclease, Pancreatic; RNA Interference; RNA, Small Interfering; Transcription Factors; Urokinase-Type Plasminogen Activator; Xenograft Model Antitumor Assays

The growth behaviour of well-differentiated neuroendocrine carcinomas of the gastro-entero-pancreatic system varies greatly and parameters predicting their prognosis are lacking. The aim of our study was to investigate whether tumour growth could be correlated with the release of proangiogenic factors into the circulation.. Circulating vascular endothelial growth factor (VEGF), interleukin-8 (IL-8), basic fibroblast growth factor (bFGF) and angiogenin were measured in 38 patients with advanced neuroendocrine carcinomas and compared to healthy age-matched controls. In 20 patients, angiogenic cytokine levels were measured at consecutive time points and correlated to tumour progression as assessed by abdominal CT scan, MRI and chromogranin A levels.. VEGF levels were elevated in patients compared to controls (P < 0.002) and clearly associated with tumour progression (P < 0.005). Angiogenin levels were significantly higher in patients than in controls (P < 0.003), while high IL-8 levels were predictive of shorter survival. Angiogenin and bFGF levels were correlated neither with tumour growth nor with patient survival.. VEGF and IL-8 are associated with tumour progression and might qualify as markers of prognosis and therapy control in patients with neuroendocrine carcinomas. Our results support the notion that specific anti-angiogenic therapies should be evaluated in neuroendocrine carcinoma patients.

Topics: Adult; Aged; Angiogenic Proteins; Biomarkers, Tumor; Case-Control Studies; Chi-Square Distribution; Female; Fibroblast Growth Factor 2; Humans; Interleukin-8; Intestinal Neoplasms; Male; Middle Aged; Neoplasm Staging; Neuroendocrine Tumors; Pancreatic Neoplasms; Predictive Value of Tests; Ribonuclease, Pancreatic; Stomach Neoplasms; Survival Rate; Vascular Endothelial Growth Factor A

We previously demonstrated the increased expression of angiogenin (ANG) in pancreatic cancer and its relation to cancer aggressiveness; however, the expression patterns and the roles of angiogenin in chronic pancreatitis are still unknown. We investigated the expression of ANG both in the tissues and in the sera of chronic pancreatitis patients (pure chronic pancreatitis) by using in situ hybridization, Western blot analysis, and enzyme-linked immunosorbent assay. In situ hybridization revealed no detectable ANG messenger RNA (mRNA) signals in all tissues of pure chronic pancreatitis and normal pancreas. Only a small amount of protein band expression was obtained in all of the protein lysates of pure chronic pancreatitis and normal pancreas. Accordingly, there was no significant difference between the mean serum ANG concentration of chronic pancreatitis patients (352.1+/-72.5 ng/ml) and that of healthy volunteers (357.6+/-45.2 ng/ml). By contrast, acinar cells and interstitial fibroblasts in the tissues surrounding pancreatic cancer showed increased ANG mRNA expression. Strong protein band expression was obtained in the protein lysates of pancreatic cancer surrounding tissue, and mean serum ANG concentration was increased in pancreatic cancer patients. These findings suggest that ANG expression is increased in pancreatic cancer surrounding tissue but is not increased in pure chronic pancreatitis, and that ANG is potentially involved in the pancreatic cancer microenvironment rather than the establishment of pure chronic pancreatitis.

Topics: Blotting, Western; Chronic Disease; Gene Expression; Humans; In Situ Hybridization; Pancreatic Neoplasms; Pancreatitis; Proteins; Reference Values; Ribonuclease, Pancreatic; RNA, Messenger

We have investigated the expression of angiogenin (ANG) in pancreatic cancer and the relevance of ANG expression to the progression of pancreatic cancer. In comparison to normal pancreas, increased ANG mRNA expression was observed in 80.0% of the cases of pancreatic cancer by in situ hybridization, and increased ANG protein expression was observed in 86.7% of the cases of pancreatic cancer using Western blot analysis. The mean serum ANG concentration of pancreatic cancer patients (566.6 +/- 191.9 ng/ml) was significantly higher (P < 2.0 x 10(-8)) than that of healthy volunteers (359.0 +/-t 59.9 ng/ml). Increased ANG mRNA expression as well as elevated serum ANG concentration correlated with poor prognosis. These findings suggest that ANG expression is up-regulated in pancreatic cancer patients and that ANG contributes to the aggressiveness of pancreatic cancer.

Topics: Adult; Aged; Aged, 80 and over; Angiogenesis Inducing Agents; Blotting, Western; Female; Humans; Male; Middle Aged; Neoplasm Proteins; Pancreatic Neoplasms; Proteins; Ribonuclease, Pancreatic; RNA, Messenger; Survival Analysis; Up-Regulation