Research Abstract |
(1) Surgical specimens. In this project, 34 esophageal squamous cell carcinomas were analyzed by comparative benomic hybridization (CGH). DNA copy number increases were found at 3q (75%), 8q23-qter (50%), 11q13 (44%), 5p14-pter (25%), 20q (25%), 7q (22%), and 2p (19%), and decreases at 18q (58%), 3p (50%), 9p (44%), 5q14-23 (39%), 4q (33%), 13q (22%), and 11q22-qter (19%). DNA amplification (high-level gain) was detected at 11q13, 2q12, 7q21, 20q11.2. The comparison of these genetic changes with clinicopathological findings revealed that lymph node metastasis of cancer was closely associated with gains of 8q23-qter (p<0.0005) and 20q (p<0.02), and loss of 11q22 (p<0.05). These results suggest that diagnosis of lymph node metastasis is estimated in bioptic specimens. Since gains of 3q and 11q13, and losses of 18q, 3p, 9p, 5q14-23 and 4q were observed in both early and advanced cancers, these are considered to be genetic alterations involved in carcinogenesis of the esophagus. (2) Cell lines. We analyzed 6 cell lines established from human esophageal squamous cell carcinomas by CGH.Gains of 3q, 5p, 7p, 8q, 11q, 13q, 17p, 20q, and Xq, and losses of 4q, 9q, and 18q were common to these 6 cell lines. Gains of 7p12-13, 11q14-22, and 11q22-qter, and losses of 4p, 8p, and 11p14-qter were found exclusively in 3 cell lines which proliferale in medium without fetal serum, whereas gains of 12p and 20p, and losses of 3p and 5q were seen only in others which need fetal serum to grow. These findings suggest that characteristics of cell proliferation are related to genetic changes of tumor cells. Genetic changes seen in cell lines were compatible with those in surgical specimens.
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