Down-regulation of p110β Expression Increases Chemosensitivity of Colon Cancer Cell Lines to Oxaliplatin

• Published in: Journal of Huazhong University of Science and Technology. Medical sciences Vol. 32; no. 2; pp. 280 - 286
• Main Author: 刘韦成 王桂华 曹小年 罗学来 李兆明 邓豫 李小兰 王诗佳 刘梦菲 胡俊波 王晶
• Format: Journal Article
• Language: English
• Published: Heidelberg Huazhong University of Science and Technology 01.04.2012; Tongji Cancer Research Institute,Tongji Hospital,Tongji Medical College,Huazhong University of Science and Technology,Wuhan 430030,China%Departement of Immunology,Tongji Medical College,Huazhong University of Science and Technology,Wuhan 430030,China
• Subjects: Antineoplastic Agents - administration & dosage; apoptosis; Apoptosis - drug effects; cancer; cell; Cell Cycle - drug effects; Cell Line, Tumor; Cell Proliferation - drug effects; Cell Survival - drug effects; cells; Class I Phosphatidylinositol 3-Kinases; colon; Colonic Neoplasms - drug therapy; Colonic Neoplasms - metabolism; Colonic Neoplasms - pathology; Dose-Response Relationship, Drug; Down-Regulation; Drug Synergism; Humans; Medicine; Medicine & Public Health; Organoplatinum Compounds - administration & dosage; oxaliplatin; Phosphatidylinositol 3-Kinases - metabolism; proliferation; cell apoptosis; oxaliplatin; p110β; colon cancer cells; cell proliferation
• ISSN: 1672-0733; 1993-1352
• DOI: 10.1007/s11596-012-0049-z

This study examined the synergetic effect of class ?A Phosphoinositide 3-kinases cata-lytic subunit p110β knockdown in conjunction with oxaliplatin treatment on colon cancer cells. Down-regulation of p110β by siRNA interference and oxaliplatin treatment were applied in colon cancer cell lines HT29, SW620 and HCT116. MTT assay was used to measure the inhibitory effect of p110β knockdown on the proliferation of colon cancer cell lines. SubG1 assay and Annexin-Ⅴ FITC/PI double-labeling cytometry were applied to detect cell apoptosis. And cell cycle was evalu-ated by using PI staining and flow cytometry. The expression of caspase 3, cleaved PARP, p-Akt, T-Akt and p110β was determined by western blotting. The results suggested that down-regulation of p110β expression by siRNA obviously reduced cell number via accumulation in G0-G1 phase of the cell cycle in the absence of notablely increased apoptosis in colon cancer cell lines HT29 and SW620 (S phase arrest in HCT116). Moreover, inhibition of p110β expression increased oxaliplatin-induced cell apoptosis and cell cycle arrest in HT29, HCT116 and SW620 cell lines. In addition, increases of cleaved caspase-3 and cleaved PARP induced by oxaliplatin treatment were determined by im-munoblotting in p110β knockdown group compared with normal control group and wild-type group. It is concluded that down-regulated expression of p110β could inhibit colon cancer cells proliferation and result in increased chemosensitivity of colorectal cancer cells to oxaliplatin through augmentation of oxaliplatin-induced cell apoptosis and cell cycle arrest.