Isolation of cancer-associated fibroblasts and its promotion to the progression of intrahepatic cholangiocarcinoma.

Intrahepatic cholangiocarcinoma is a highly fatal tumor characterized by an abundant stromal environment. Cancer-associated fibroblasts play key roles in tumor growth and invasiveness and have been regarded as a potential therapeutic target. This study was designed to isolate human primary cancer-associated fibroblasts of intrahepatic cholangiocarcinoma to study tumor-stroma interactions and to analyze the clinical relevance of alpha-smooth muscle actin -positive cancer-associated fibroblasts in patients with intrahepatic cholangiocarcinoma. The isolated cancer-associated fibroblasts were positive for alpha-smooth actin, fibroblast-specific protein-1, fibroblast activation protein, and PDGFR-β. In addition, cancer-associated fibroblasts were found to increase proliferation, migration, and invasion of cholangiocarcinoma cells in vitro and promote tumor growth of mice in vivo. Moreover, alpha-smooth muscle actin-positive expression of cancer-associated fibroblasts predicted unfavorable prognosis in patients with intrahepatic cholangiocarcinoma and showed correlation with presence of lymph node metastasis. This study may provide a useful tool to investigate further effect of cancer-associated fibroblasts on the molecular mechanism of cholangiocarcinoma cells as well as contribution of cancer-associated fibroblasts in lymphangiogenesis and lymph node metastasis.