Octreotide,a somatostatin analogue,inhibits the growth of cholangiocarcinoma cells

Objective To investigate the possible mechanism underlying in-vivo and in-vitro growth inhibition of cholangiocarcinoma cell line QBC939 by octreotide(OCT),a somatostatin analogue.Methods Cholangiocarcinoma cell line QBC939 were cultured in vitro.MTT assay were used to determine the antiproliferative effect of different OCT doses on QBC939 cell growth rate.Changes in QBC939 cell cycle after OCT administration were evaluated by flow cytometry.The effects of OCT on the expression of P27KIP1 were evaluated by immunochemistry.Nude mouse models of tumor heterograft were established and used for further evaluation of OCT antiproliferative effects.Results MTT assay showed that OCT significantly reduced QBC939 cell growth in a dose-dependent pattern.After treated with 0.005～5 mg/L OCT for 48 hours,the cell growth rates were 83.8%,80.28%,77.53% and 65.32%,respectively.Between control group and experimental groups,the A values were significantly different(P0.01).Results of flow cytometry suggested that OCT accounted for increased arrest of cell cycle in G0/G1 phase(P0.05).Expression of P27KIP1 was dose-dependently enhanced with octreotide treatment.The weights of QBC939 xenografts in OCT-treated group were lower than those in the control group.Conclusion OCT appeared to inhibit the growth of human extrahepatic cholangiocarcinoma cell line QBC939 at least partly in a dose-dependent pattern.Cell cycle arrest underlying such effects may be correlated with the up-regulation of P27KIP1.