title: Upregulation of endothelial nitric oxide synthase (eNOS) and its upstream regulators in Opisthorchis viverrini associated cholangiocarcinoma and its clinical significance.
abstract: Endothelial nitric oxide synthase (eNOS) is an isoform of the enzyme nitric oxide synthase (NOS) which is constitutively expressed in endothelial cells and plays important roles in vasodilation. We previously reported the importance of eNOS activation in cholangiocarcinoma (CCA) tissues and cell lines. The present study aims to investigate the relative abundance of eNOS and phosphorylated eNOS (P-eNOS) and their upstream regulators VEGFR3, VEGFC, EphA3 and ephrin-A1, in the Opisthorchis viverrini (Ov)/N-nitrosodimethylamine (NDMA)-induced hamster CCA model and in human CCA by semiquantitative immunohistochemical analysis of the relevant tissues. Results from the hamster model suggested an increase in eNOS and P-eNOS and upstream regulators during CCA genesis. In human CCA, high immunohistochemical staining intensity of all investigated proteins was associated with the presence of metastasis. A pairwise analysis of the staining data for eNOS and its upstream regulators showed that a concurrent increase in eNOS/VEGFR3, eNOS/ephrin-A1, eNOS/VEGFC and eNOS/EphA3 was significantly associated with metastasis. An increase in eNOS/VEGFR3, eNOS/ephrin-A1 was also associated with non-papillary type CCA. Additionally, an increase in eNOS and P-eNOS was significantly correlated with a high micro-vessel level (P=0.04). Our results indicate that the development of CCA involves upregulation of eNOS and P-eNOS and their regulators. This may drive angiogenesis and metastasis in CCA.
authors.affiliation: Department of Biochemistry, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand; Liver Fluke and Cholangiocarcinoma Research Center, Khon Kaen University, Khon Kaen 40002, Thailand.
authors.forename: Manida
authors.initials: M
authors.lastname: Suksawat
authors.affiliation: Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen 40002, Thailand; Liver Fluke and Cholangiocarcinoma Research Center, Khon Kaen University, Khon Kaen 40002, Thailand; Cholangiocarcinoma Screening and Care Program (CASCAP), Khon Kaen University, Khon Kaen 40002, Thailand.
authors.forename: Anchalee
authors.initials: A
authors.lastname: Techasen
authors.affiliation: Department of Biochemistry, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand; Liver Fluke and Cholangiocarcinoma Research Center, Khon Kaen University, Khon Kaen 40002, Thailand; Cholangiocarcinoma Screening and Care Program (CASCAP), Khon Kaen University, Khon Kaen 40002, Thailand.
authors.forename: Nisana
authors.initials: N
authors.lastname: Namwat
authors.affiliation: Department of Biochemistry, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand; Liver Fluke and Cholangiocarcinoma Research Center, Khon Kaen University, Khon Kaen 40002, Thailand; Cholangiocarcinoma Screening and Care Program (CASCAP), Khon Kaen University, Khon Kaen 40002, Thailand.
authors.forename: Puangrat
authors.initials: P
authors.lastname: Yongvanit
authors.affiliation: Department of Surgery, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand; Liver Fluke and Cholangiocarcinoma Research Center, Khon Kaen University, Khon Kaen 40002, Thailand; Cholangiocarcinoma Screening and Care Program (CASCAP), Khon Kaen University, Khon Kaen 40002, Thailand.
authors.forename: Narong
authors.initials: N
authors.lastname: Khuntikeo
authors.affiliation: Department of Surgery, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand; Liver Fluke and Cholangiocarcinoma Research Center, Khon Kaen University, Khon Kaen 40002, Thailand; Cholangiocarcinoma Screening and Care Program (CASCAP), Khon Kaen University, Khon Kaen 40002, Thailand.
authors.forename: Attapon
authors.initials: A
authors.lastname: Titapun
authors.affiliation: Department of Pathology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand; Liver Fluke and Cholangiocarcinoma Research Center, Khon Kaen University, Khon Kaen 40002, Thailand; Cholangiocarcinoma Screening and Care Program (CASCAP), Khon Kaen University, Khon Kaen 40002, Thailand.
authors.forename: Supinda
authors.initials: S
authors.lastname: Koonmee
authors.affiliation: Department of Biochemistry, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand; Liver Fluke and Cholangiocarcinoma Research Center, Khon Kaen University, Khon Kaen 40002, Thailand; Cholangiocarcinoma Screening and Care Program (CASCAP), Khon Kaen University, Khon Kaen 40002, Thailand. Electronic address: watloi@yahoo.com.
authors.forename: Watcharin
authors.initials: W
authors.lastname: Loilome
mesh_terms: D000328:Adult; D000368:Aged; D000818:Animals; D001650:Bile Duct Neoplasms / Q000139:chemically induced / Q000378:metabolism* / Q000469:parasitology; D018281:Cholangiocarcinoma / Q000139:chemically induced / Q000378:metabolism* / Q000469:parasitology; D006224:Cricetinae; D004128:Dimethylnitrosamine; D005260:Female; D006801:Humans; D008297:Male; D008647:Mesocricetus; D008875:Middle Aged; D052250:Nitric Oxide Synthase Type III / Q000235:genetics* / Q000378:metabolism; D009889:Opisthorchiasis / Q000150:complications / Q000378:metabolism* / Q000469:parasitology; D009891:Opisthorchis / Q000502:physiology; D015854:Up-Regulation
chemical_list: C496314:NOS3 protein, human; D052250:Nitric Oxide Synthase Type III; D004128:Dimethylnitrosamine
keywords: Cholangiocarcinoma; Opisthorchis viverrini (Ov); eNOS