title: The involvement of K(v)3.4 voltage-gated potassium channel in the growth of an oral squamous cell carcinoma cell line.
abstract: BACKGROUND
  In our previous study, an A-type voltage-gated K(+) channel, K(v)3.4, was found more frequently expressed in oral squamous cell carcinoma (OSCC) when compared with non-cancerous matched oral tissue. An OSCC cell line, OECM-1, was found to have moderate level of K(v)3.4 expression.
  
  
  METHODS
  To further elucidate the roles of K(v)3.4 for the involvement of neoplastic process, we amplified K(v)3.4 coding sequence by reverse transcriptase polymerase chain reaction (RT-PCR), constructed an expression vector carrying this sequence and then stably transfected into OECM-1 OSCC cells.
  
  
  RESULTS
  We demonstrated the integration and constitutive expression of K(v)3.4 in the cell. A unique A-type current elicited by such expression in OECM-1 cells was defined by patch clamp analysis. This current pattern can be reversibly blocked by an A-type K(+) channel blocker 2 mM 4-aminopyridine (4-AP). The acquisition of K(v)3.4 activity in OECM-1 cells bestowed growth advantage. However, in 3T3 cell, transfected K(v)3.4 caused only limited increase of growth without forming transformation foci.
  
  
  CONCLUSIONS
  The present study established a stable keratinocyte system carrying functional K(v)3.4 and increase of growth, by which the anti-K(v)3.4 modalities for potential OSCC control can be further investigated.
authors.affiliation: Institute of Physiology, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Tien-Shen
authors.initials: TS
authors.lastname: Lew
authors.forename: Che-Shoa
authors.initials: CS
authors.lastname: Chang
authors.forename: Kung-Ping
authors.initials: KP
authors.lastname: Fang
authors.forename: Chian-Yi
authors.initials: CY
authors.lastname: Chen
authors.forename: Cheng-Hsiung
authors.initials: CH
authors.lastname: Chen
authors.forename: Shu-Chun
authors.initials: SC
authors.lastname: Lin
mesh_terms: D016475:3T3 Cells; D015761:4-Aminopyridine / Q000494:pharmacology; D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000818:Animals; D002294:Carcinoma, Squamous Cell / Q000473:pathology*; D002455:Cell Division; D045744:Cell Line, Tumor; D002470:Cell Survival; D015972:Gene Expression Regulation, Neoplastic; D015603:Keratinocytes / Q000473:pathology; D051379:Mice; D009062:Mouth Neoplasms / Q000473:pathology*; D018408:Patch-Clamp Techniques; D026902:Potassium Channel Blockers / Q000494:pharmacology; D024642:Potassium Channels, Voltage-Gated / Q000032:analysis / Q000037:antagonists & inhibitors / Q000502:physiology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014162:Transfection
chemical_list: D026902:Potassium Channel Blockers; D024642:Potassium Channels, Voltage-Gated; D015761:4-Aminopyridine