Tumor-derived trypsin enhances proliferation of intrahepatic cholangiocarcinoma cells by activating protease-activated receptor-2

Abstract

Abstract. In primary malignant liver tumors, trypsinogenimmunoreactivity was present in 70% of intrahepatic cholangiocarcinoma (ICC) specimens, but absent in hepatocellular carcinoma (HCC) specimens. We suggest the secretion of trypsinogen to be a key difference in biological behavior between ICC and HCC cells. The purpose of this study was to investigate the secretion of tumor-derived trypsin and the expression of its specific receptor, protease-activated receptor-2 (PAR-2), in ICC using cell lines and surgical specimens. The expression of trypsinogen-1 mRNA was observed in three of four ICC cell lines, but none of three HCC cell lines. Western blot analysis detected trypsinogen-1 in serum-free conditioned medium from one of the ICC cell lines positive for the mRNA. Gelatin zymography revealed a gelatinolytic activity for trypsin, the activated form of trypsinogen, in the same conditioned medium. PAR-2 mRNA and protein were observed in ICC cell lines. The proliferative activity of ICC cells was increased by concentrations of trypsin as low as 10 nM, and peaked at 100 nM. The effect of trypsin was suppressed by a serine protease inhibitor, gabexate mesilate. PAR-2 expression was detected in 64% of ICC surgical specimens immunohistochemically. In addition, stroma fibroblasts expressed PAR-2 in 52% of ICC specimens. These results suggest that trypsinogen-1 contributes to the growth of ICC cells and also tumor-associated fibroblasts.

Autocrine Extra-Pancreatic Trypsin 3 Secretion Promotes Cell Proliferation and Survival in Esophageal Adenocarcinoma

“…Both TAT-1 and TAT-2 have identical cDNAs and protein sequences and similar substrate specificities to their non-malignant counterparts, pancreatic trypsinogen-1 and -2 respectively, but differ in their susceptibility to inhibition by protease inhibitors. Other investigators have studied and reported TAT-1/TAT-2 expression in various tumors such as pancreatic, colon, gastric cancers including recently in intrahepatic cholangiocarcinoma cells [18], [19]. Later, Cottrell et al demonstrated trypsinogen-3 (namely mesotrypsinogen) or its splicing variant (namely trypsinogen IV) in tumor-derived epithelial cell lines as well as in normal human colonic mucosa.…”

Sodium valproate blocks the transforming growth factor (TGF)-β1 autocrine loop and attenuates the TGF-β1-induced collagen synthesis in a human hepatic stellate cell line

“…It was reported that the synthesis of collagens and TGF-β1 were not effectively inhibited when transition into myofibroblasts had already occurred (1). We received LI90 cells from passages [16][17][18], and most of them showed myofibroblast-like morphology after 24 h of incubation (data not shown). Therefore, we concluded that cells had been already activated when treatment with VPA began.…”

“…After culturing for 7 days on Lab-Tek chamber slides (Nalge Nunc International), cells were fixed in a mixture of methanol and acetone (1:1) for 15 min. Immunostaining was performed as described (16). Briefly, the slides were blocked with normal goat serum [5% in phosphatebuffered saline (PBS)] and incubated with a mouse monoclonal antibody against αSMA (1:100) (Santa Cruz Biotechnology) or a rabbit polyclonal antibody to COL1A1 (1:100) (Santa Cruz Biotechnology) at 4˚C overnight.…”

PRSS3 expression is associated with tumor progression and poor prognosis in epithelial ovarian cancer

“…Proteases that are aberrantly expressed in tumor cells or secreted by tumor-associated stromal cells perform specific functions to facilitate the various steps of tumorigenesis [6]. Proteases activate chemokines, growth factors, growth factor receptors, and other signaling receptors, contributing to the signaling cascades involved in tumor initiation, proliferation, and metastasis [7].…”