Comparative genomic hybridization analysis reveals 3q gain resulting in genetic alteration in 3q in advanced oral squamous cell carcinoma.

We analyzed DNA sequence copy number aberrations (DSCNAs) in 17 primary oral squamous cell carcinomas (OSCCs) by comparative genomic hybridization. DSCNAs were detected frequently at 3q25-qter (7/17), Xp21 (5/17), and Xq12-q23 and 8q23-q24 (4/17), and losses were detected frequently at 13q21-q22 (5/17), 3p21-pter, 4p15-pter and 17p13 (4/17), and 8p22-pter and 9p21-pter (3/17). Four tumors showed amplifications of seven loci: 3q11-qter, 3q13, 3q26, 7q21-q22, 8q23-qter, 9p22-pter, and 12p11. The total number of DSCNAs was significantly greater in stage III and stage IV tumors than in stage I and stage II tumors (P=.008). Furthermore, 3q gain was detected preferentially in stage III and stage IV tumors (6/8) rather than in stage I and stage II tumors (1/9, P=.013). In our study, all tumors with gain of 3q also contained one or more loss(es) in common regions. On the other hand, all tumors with gain of 9p did not contain 3q gains. These observations indicate that gain of 3q and accumulation of DSCNAs are strongly associated with tumor progression in OSCC. Furthermore, 3q gain and loss of one or more additional loci in common aberration regions appears to be a group of DSCNs associated with dominant genetic pathways of leading to advanced OSCCs.