COMPARISON OF DNA COPY NUMBERS IN ORIGINAL ORAL SQUAMOUS-CELL CARCINOMAS AND CORRESPONDING CELL-LINES BY COMPARATIVE GENOMIC HYBRIDIZATION

We analyzed regional DNA copy numbers in 4 oral squamous cell carcinom as (SCCs) by using comparative genomic hybridization, and compared the m with those in cell lines derived from the SCCs, In the original tumo rs, DNA copy number increases were observed on chromosomes 5p (4/4 cas es), 89 (4/4), 20p (3/5), 3q (2/4), 59 (2/4), 7p (2/4), 79 (2/4), 11p (2/4), 11q (2/4) and 13q (2/4), Although most of these changes have be en described previously for SCC tumors in the head and neck, the incid ence of increases in 8q and 20p was much higher in the present study; this map be important in relation to cell line establishment, since 89 contains c-myc, which is involved in immortalization. No common chrom osomal region with DNA copy number decreases was observed, except for 18q (2/4), When the original tumors and the cell lines were compared, their profiles were essentially similar with one exception, Further, t here Has no region that commonly changed in the cell lines, but not in the original tumors, suggesting that the DNA copy number changes obse rved in the cell lines mostly represent those of the original tumors.