Comparison of chromosomal aberrations between primary tumors and their synchronous lymph-node metastases in intestinal-type gastric carcinoma

Lymph-node metastasis is a main factor causing poor prognosis of patients with gastric cancer (GC). In order to determine the genes involved in lymph-node metastasis, we compared primary tumors with their synchronous lymph-node metastases for DNA sequence copy number aberrations (DSCNAs) in 20 patients diagnosed as having intestinal-type GC using comparative genomic hybridization (CGH). The results showed that some DSCNAs (gains at 8q, 13q, 5p, 7 and X, and losses at 1p, 17p, 19, 21q and 22q) were frequently found in both primary tumors and their metastases. However, metastases often contained DSCNAs that were not found in corresponding primary tumors, and gain at 20q12-13 and losses at 21qcen-21, 4q and 14q22-ter were significantly more frequently observed in metastatic lesions than in their primary tumors (10:2, 9:0, 6:0, and 7:0 between metastases and corresponding primary tumors, respectively). Our data indicate that gain at 20q12-13 and losses at 21qcen-21, 4q, and 14q22-ter are involved in lymph-node metastases, and that these chromosomal regions may contain the genes related to lymph-node metastases in intestinal-type GC.