title: Effects of Intermediate-Conductance Ca(2+)-Activated K(+) Channels on Human Endometrial Carcinoma Cells.
abstract: The objective of this study was to investigate the effect of intermediate-conductance Ca(2+)-activated K(+) (KCa3.1) channels on the cell proliferation, cell cycle, apoptosis, migration, and invasion in endometrial cancer (EC) cells. Human EC cell lines HEC-1-A and Ishikawa were cultured in vitro and transfected with recombinant plasmid containing KCa3.1-targeting shRNA. RT-qPCR and Western blot were used to examine the mRNA and protein expression levels of KCa3.1 channels in transfected cells. In addition, the specific inhibitor of KCa3.1, TRAM-34, was used to examine the effect of KCa3.1 blockage on migration capacity and invasiveness of EC cells using transwell assay. Proliferation and apoptotic rates of EC cells transfected with KCa3.1 shRNA or treated with TRAM-34 were analyzed using MTT, BrdU incorporation assay, and flow cytometry. Expression of cell cycle proteins and metalloproteinase-2 (MMP-2) was evaluated by RT-qPCR and Western blotting. TRAM-34 treatment and KCa3.1 silencing using shRNA dramatically suppressed both the mRNA and protein expression of KCa3.1 channels (P < 0.01) compared with control groups. Blockage of KCa3.1 by TRAM-34 treatment and KCa3.1 shRNA transfection exerted inhibitory effect on cell growth of both EC cell lines, as demonstrated by increased cell population at G0-G1 phase and decreased cell population at S phase. However, both the treatments did not result in significant changes in the apoptotic rate (P > 0.05) compared to controls. Protein expressions of cyclin D1, cyclin E, and survivin were significantly decreased in the experimental groups comparing to control. We showed that TRAM-34 treatment led to significantly inhibited migration, invasion, and MMP-2 expression in HEC-1-A and Ishikawa cells, compared with the control group (P < 0.01). Blockage of KCa3.1 channel activity or expression inhibits cell proliferation and cell cycle progression without inducing apoptosis in EC cells. Moreover, TRAM-34 could reduce the ability of EC cells to migrate and invade, which might be related to reduced expression of MMP-2.
authors.affiliation: Department of Gynecologic Oncology, Zhejiang Cancer Hospital, 38 Guangji Road, Hangzhou, 310022, China.
authors.forename: Yingli
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Shanghai Jiao Tong University Affiliated First People's Hospital, Shanghai, 200080, China.
authors.forename: Youji
authors.initials: Y
authors.lastname: Feng
authors.affiliation: Department of Gynecologic Oncology, Zhejiang Cancer Hospital, 38 Guangji Road, Hangzhou, 310022, China. chenlu@zjcc.org.cn.
authors.forename: Lu
authors.initials: L
authors.lastname: Chen
authors.affiliation: Department of Gynecologic Oncology, Zhejiang Cancer Hospital, 38 Guangji Road, Hangzhou, 310022, China.
authors.forename: Jianqing
authors.initials: J
authors.lastname: Zhu
mesh_terms: D017209:Apoptosis; D002277:Carcinoma / Q000378:metabolism*; D045744:Cell Line, Tumor; D002465:Cell Movement; D019938:Cyclin D1 / Q000235:genetics / Q000378:metabolism; D016889:Endometrial Neoplasms / Q000378:metabolism*; D005260:Female; D006801:Humans; D051034:Inhibitor of Apoptosis Proteins / Q000235:genetics / Q000378:metabolism; D051660:Intermediate-Conductance Calcium-Activated Potassium Channels / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D020778:Matrix Metalloproteinase 2 / Q000235:genetics / Q000378:metabolism; D026902:Potassium Channel Blockers / Q000494:pharmacology; D011720:Pyrazoles / Q000494:pharmacology; D000077022:Survivin
chemical_list: C107489:BIRC5 protein, human; D051034:Inhibitor of Apoptosis Proteins; D051660:Intermediate-Conductance Calcium-Activated Potassium Channels; C496923:KCNN4 protein, human; D026902:Potassium Channel Blockers; D011720:Pyrazoles; D000077022:Survivin; C411671:TRAM 34; D019938:Cyclin D1; C522361:MMP2 protein, human; D020778:Matrix Metalloproteinase 2
keywords: Apoptosis; Cell cycle; Cell proliferation; Endometrial carcinoma; Intermediate-conductance Ca2+-activated K+ channels; Invasion; Migration; RNA interference