The increase of voltage-gated potassium channel Kv3.4 mRNA expression in oral squamous cell carcinoma.
BACKGROUND
Potassium channels have been reported to be involved in the proliferation of many types of cells, including tumor cells. The overexpression of the K+ channel and related channel activity are involved in the neoplastic process.


METHODS
We examined the expression of an A-type voltage-gated K+ channel, Kv3.4, in oral squamous cell carcinoma (OSCC) and esophageal squamous cell carcinoma (ESCC) compared with non-cancerous matched tissue (NCMT) using RT-PCR analysis. In addition, administration of an A-type K+ channel blocker, 4-aminopyridine (4-AP), and an antisense oligodeoxynucleotide (ODN) directed specifically against Kv3.4 were performed to identify the involvement of Kv3.4 in the growth of OSCC cells.


RESULTS
A significantly increase in the frequency of Kv3.4 mRNA expression was identified in OSCC (64%) compared to corresponding NCMT (29%) (P = 0.05). The increase of Kv3.4 mRNA expression was also eminent in ESCC. Growth of OSCC cells was significantly inhibited by 4-AP in a dose-dependent manner at different time point of treatment. In OECM-1 OSCC cells, a significant growth inhibition was noted in antisense ODN-treated cells compared to control cells.


CONCLUSIONS
We provide novel evidences of the increase of Kv3.4 mRNA expression in OSCC. The abrogation of Kv3.4 inhibits the growth of OSCC cells.
Chang
Kuo-Wei
KW
The School of Dentistry, National Yang-Ming University, Taipei, Taiwan.
Yuan
Ta-Chun
TC
Fang
Kung-Ping
KP
Yang
Feng-Shuo
FS
Liu
Chung-Ji
CJ
Chang
Che-Shoa
CS
Lin
Shu-Chun
SC
D015761:4-Aminopyridine / Q000494:pharmacology; D002294:Carcinoma, Squamous Cell / Q000235:genetics*; D002455:Cell Division / Q000187:drug effects / Q000235:genetics; D002460:Cell Line; D045744:Cell Line, Tumor; D004305:Dose-Response Relationship, Drug; D004938:Esophageal Neoplasms / Q000235:genetics; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics; D006801:Humans; D015603:Keratinocytes / Q000187:drug effects / Q000378:metabolism; D009062:Mouth Neoplasms / Q000235:genetics*; D016376:Oligonucleotides, Antisense / Q000494:pharmacology; D026902:Potassium Channel Blockers / Q000494:pharmacology; D015221:Potassium Channels / Q000187:drug effects / Q000235:genetics*; D024642:Potassium Channels, Voltage-Gated / Q000037:antagonists & inhibitors / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics*; D051670:Shaw Potassium Channels
C492015:KCNC4 protein, human; D016376:Oligonucleotides, Antisense; D026902:Potassium Channel Blockers; D015221:Potassium Channels; D024642:Potassium Channels, Voltage-Gated; D012333:RNA, Messenger; D051670:Shaw Potassium Channels; D015761:4-Aminopyridine