Cytogenetic analysis of esophageal squamous cell carcinoma cell lines by comparative genomic hybridization: Relationship of cytogenetic aberrations to in vitro cell growth

Cancer is characterized by autonomous growth of cells, and it is widely acc epted that cell proliferation is primarily influenced by individual cell ge netics. To elucidate the mechanisms of cancer cell proliferation, we studie d differences in genetic aberrations for different type of tumors with diff erent proliferation characteristics. We employed comparative genomic hybrid ization (CGH) to detect genetic aberrations in six cell lines of esophageal squamous cell carcinoma (ESCC). Three cell lines (YES-1, -2, and -3) grow in culture without fetal calf serum (group A), while others require serum t o be maintained in vitro (group B). Both groups showed very similar cytogen etic aberrations: over-representations of 11q13 (6/6), 8q23-qter(5/6), Xq25 -qter (5/6), 3q26-qter (4/6), 5p (4/6), 7p15-pter(4/6), 8q21.3-q22 (4/6), 1 7p (4/6), and 20q13 (4/6), and under-representations of 18q21-qter (6/6), 4 q28-q33 (4/6), and 9p21 (4/6). Six amplification loci were mopped to chromo somal regions of 6q23 (1 case), 7p12 (2 cases), 9p21 (1 case), 11p11.2-12 ( 3 cases), 11q13 (2 cases), and 17p12 (2 cases). However, some differences w ere detected. DNA copy number increases at 7p12-p13, 11q14-q22, and 11q22-q ter and under-representations of 4p, 8p, and 11p14-pter. In contrast, gains at 12p and 20p, and losses at 3p and 5q were detected only in group-B cell lines. These observations suggest that cytogenetic differences between the two groups may be linked to differences in cell growth characteristics in vitro, and that the genes in these chromosomal regions may play important r oles in cell proliferation. (C) Elsevier Science Inc., 2000. All rights res erved.