Somatic mutations in the D-loop of mitochondrial DNA in oral squamous cell carcinoma.
We aimed to characterize somatic mutations in the D-loop of mitochondrial DNA (mtDNA) and their impact on survival in oral squamous cell carcinoma patients in an endemic betel quid chewing area. Histologically confirmed oral cancer and corresponding non-tumor tissues were obtained from 59 patients. The D-loop of mtDNA sequence in a patient's non-cancerous tissues was compared with that of paired oral cancer samples and any sequence differences were identified as somatic mutations. With a median follow-up of 16 months, somatic mutations of the D-loop were observed in 38 (64.4%) patients and most of them occurred in the poly-C tract. There was no significant difference between the mutation group and non-mutation group in age, gender, primary site, histological features, pathological stage, smoking, betel quid chewing, alcohol consumption, and postoperative radiotherapy. However, patients with D-loop mutations have better survival (2 year disease specific survival rate: 73.4 vs. 45.0%, P = 0.0374). A high rate of somatic mutations in the D-loop region of mtDNA was found in betel quid-related oral squamous cell carcinoma patients. Somatic mutation of D-loop of mtDNA was associated with better survival.
Department of Otolaryngology, Taichung Veterans General Hospital, Taichung, Taiwan.
Shih-An
SA
Liu
Rong-San
RS
Jiang
Fun-Jou
FJ
Chen
Wen-Yi
WY
Wang
Jin-Ching
JC
Lin
D002294:Carcinoma, Squamous Cell / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D004272:DNA, Mitochondrial / Q000235:genetics*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D008928:Mitochondria / Q000235:genetics*; D009062:Mouth Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D009154:Mutation; D012189:Retrospective Studies
D004272:DNA, Mitochondrial