title: Omi/HtrA2 pro-apoptotic marker differs in various hepatocellular carcinoma cell lines owing to ped/pea-15 expression level.
abstract: Omi/HtrA2 promotes cell apoptosis in human cancer cells. Early studies showed that primary hepatocellular carcinoma requires Omi/HtrA2 expression for cell apoptosis. Additionally, the Omi/HtrA2 pro-apoptotic marker demonstrated a difference in some cell types. However, how the Omi/HtrA2 pro-apoptotic marker reacts during the process of hepatocellular carcinoma cell apoptosis remains to be determined. Thus, we investigated the role and possible mechanism of Omi/HtrA2 on hepatocellular carcinoma cell apoptosis using various hepatocellular carcinoma cell lines. The results were analyzed using RT‑qPCR and western blot analysis. In the present study, we found that Omi/HtrA2 was overexpressed in hepatocellular carcinoma cell lines and induced hepatocellular carcinoma cell apoptosis. Additiionally, the only manner in which Omi/HtrA2 participated in cell death in PLC cells may be dependent on IAP-binding. Omi/HtrA2‑inducing HepG2 cell apoptosis may mainly depend on its serine protease activity while both IAP-binding and its serine protease activity participated in Hep3B cell apoptosis. This result suggested that Omi/HtrA2 pro-apoptotic marker differs in various hepatocellular carcinoma cell lines. PLC cells were also devoid of the expression of ped/pea-15 as the substrate of Omi/HtrA2 serine protease while ped/pea-15 was overexpressed in HepG2 and Hep3B cells and ped/pea-15 expression was higher in HepG2 cells than that in Hep3B cells. These results showed that Omi/HtrA2 overexpression promotes hepatocellular carcinoma cell apoptosis and the ped/pea-15 expression level causes this difference of the Omi/HtrA2 pro-apoptotic marker in the various hepatocellular carcinoma cell lines.
authors.affiliation: Deparment of Hepatic Oncology, Jiangxi Provincial Cancer Hospital, Nanchang 330029, P.R. China.
authors.forename: Zongquan
authors.initials: Z
authors.lastname: Xu
authors.affiliation: Deparment of Hepatic Oncology, Jiangxi Provincial Cancer Hospital, Nanchang 330029, P.R. China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Deparment of Hepatic Oncology, Jiangxi Provincial Cancer Hospital, Nanchang 330029, P.R. China.
authors.forename: Guohui
authors.initials: G
authors.lastname: Xu
authors.affiliation: Department of Hepatobiliary Surgery, Qilu Hospital, Shandong University, Jinan 250012, P.R. China.
authors.forename: Cheng
authors.initials: C
authors.lastname: Peng
authors.affiliation: Department of Hepatobiliary Surgery, Qilu Hospital, Shandong University, Jinan 250012, P.R. China.
authors.forename: Enyu
authors.initials: E
authors.lastname: Liu
authors.affiliation: Department of Hepatobiliary Surgery, Qilu Hospital, Shandong University, Jinan 250012, P.R. China.
authors.forename: Yunguang
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Hepatobiliary Surgery, Qilu Hospital, Shandong University, Jinan 250012, P.R. China.
authors.forename: Jun
authors.initials: J
authors.lastname: Niu
authors.affiliation: Hepatic Surgery Center Affiliated Tongji Hospital, Tongji Medical College of HuaZhong University of Science and Technology, Wuhan 430030, P.R. China.
authors.forename: Changhai
authors.initials: C
authors.lastname: Li
mesh_terms: D017209:Apoptosis; D051017:Apoptosis Regulatory Proteins; D006528:Carcinoma, Hepatocellular / Q000473:pathology*; D045744:Cell Line, Tumor; D002470:Cell Survival; D005434:Flow Cytometry; D015972:Gene Expression Regulation, Neoplastic; D020868:Gene Silencing; D005819:Genetic Markers; D049452:Green Fluorescent Proteins / Q000378:metabolism; D056945:Hep G2 Cells; D000074923:High-Temperature Requirement A Serine Peptidase 2; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D008113:Liver Neoplasms / Q000473:pathology*; D008928:Mitochondria / Q000378:metabolism; D024101:Mitochondrial Proteins / Q000378:metabolism*; D010750:Phosphoproteins / Q000378:metabolism*; D011485:Protein Binding; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000378:metabolism; D012697:Serine Endopeptidases / Q000378:metabolism*; D057057:Serine Proteases / Q000378:metabolism
chemical_list: D051017:Apoptosis Regulatory Proteins; D005819:Genetic Markers; D047908:Intracellular Signaling Peptides and Proteins; D024101:Mitochondrial Proteins; C092039:PEA15 protein, human; D010750:Phosphoproteins; D034741:RNA, Small Interfering; D049452:Green Fluorescent Proteins; D057057:Serine Proteases; D012697:Serine Endopeptidases; C000615914:HTRA2 protein, human; D000074923:High-Temperature Requirement A Serine Peptidase 2