Sookruetai Boonmasawai. The effects of human cholangiocarcinoma cell culture on endothelial cell functions. Doctoral Degree(Pharmacology). Mahidol University. Mahidol University Library and Knowledge Center. : Mahidol University, 2007.
The effects of human cholangiocarcinoma cell culture on endothelial cell functions
Abstract:
Angiogenesis is the new blood vessel formation out of pre-existing capillaries. It is a complex process which enhance tumor progression. Human cholangiocarcinoma (HuCCA) is high incidence malignancy of biliary tracts occurring in the North-eastern region of Thailand. To understand the unknown mechanism of tumor induced angiogenesis in HuCCA, experiments were designed to explore the effects of HuCCA on endothelial cell functions and cellular mechanisms. This research found that HuCCA could induce human umbilical vein endothelial cell (HUVEC) proliferations, migrations and COX-2 protein expression. The signaling mechanism HuCCA-conditioned medium (CM) induced the proliferations of HUVEC involved the COX-2 dependent and COX-2 independent pathway. The COX-2 dependent angiogenesis was activated through protein kinase C and mitogen activated protein kinase kinase (MAPKK) and could be inhibited by NS-398, aspirin and indomethacin. The preferentially COX-3 inhibitors, acetaminophen, dipyrone and phenacetin, also inhibited the proliferation of HuCCA-CM induced endothelial cells. While HUVEC proliferation in the COX-2 independent pathway was induced via VEGFR-2 (KDR/Flt-1), endothelial cell proliferation was also induced via the COX-2 dependent adenylate cyclase signaling mechanism. This understanding of tumor derived angiogenesis regulation will lead to the development of preventative and novel therapeutic approaches.