title: Silencing of Kv4.1 potassium channels inhibits cell proliferation of tumorigenic human mammary epithelial cells.
abstract: Potassium channel activity has been shown to facilitate cell proliferation in cancer cells. In the present study, the role of Kv4.1 channels in immortal and tumorigenic human mammary epithelial cells was investigated. Kv4.1 protein expression was positively correlated with tumorigenicity. Moreover, transfection with siRNAs targeting Kv4.1 mRNA suppressed proliferation of tumorigenic mammary epithelial cells. Experiments using mRNA isolated from human breast cancer tissues revealed that the level of Kv4.1 mRNA expression varied depending on the stage of the tumor. Kv4.1 protein expression increased during stages T2 and T3 compared to normal tissue. These results demonstrated that Kv4.1 plays a role in proliferation of tumorigenic human mammary epithelial cells. In addition, elevated Kv4.1 expression may be useful as a diagnostic marker for staging mammary tumors and selective blockers of Kv4.1 may serve to suppress tumor cell proliferation.
authors.affiliation: Laboratories of Veterinary Pharmacology, College of Veterinary Medicine, Seoul National University, San 56-1 Sillim-Dong Kwanak-Gu, Seoul 151-742, South Korea.
authors.forename: Soo Hwa
authors.initials: SH
authors.lastname: Jang
authors.forename: Changsun
authors.initials: C
authors.lastname: Choi
authors.forename: Seong-Geun
authors.initials: SG
authors.lastname: Hong
authors.forename: Oleg V
authors.initials: OV
authors.lastname: Yarishkin
authors.forename: Young Min
authors.initials: YM
authors.lastname: Bae
authors.forename: Jae Gon
authors.initials: JG
authors.lastname: Kim
authors.forename: Scott M
authors.initials: SM
authors.lastname: O'Grady
authors.forename: Kyong-Ah
authors.initials: KA
authors.lastname: Yoon
authors.forename: Kyung-Sun
authors.initials: KS
authors.lastname: Kang
authors.forename: Pan Dong
authors.initials: PD
authors.lastname: Ryu
authors.forename: So Yeong
authors.initials: SY
authors.lastname: Lee
mesh_terms: D001943:Breast Neoplasms / Q000378:metabolism / Q000473:pathology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D020868:Gene Silencing; D006801:Humans; D034741:RNA, Small Interfering / Q000235:genetics; D051672:Shal Potassium Channels / Q000037:antagonists & inhibitors / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D034741:RNA, Small Interfering; D051672:Shal Potassium Channels