RET/PTC rearrangements in thyroid carcinomas from Korea

1625 Objectives: Rearrangement or RET gene, RET/PTC rearrangement, is the common genetic alterations in thyroid papillary carcinomas. The prevalence of RET/PTC alterations in thyroid carcinomas shows significant geographical variations. The purpose of this study is to investigate the frequency and types of RET/PTC rearrangements in thyroid carcinomas from Korea. Methods: Thyroid cancer tissues were obtained from 16 patients. We isolated total RNA from tissues and reverse transcribed cDNA using Superscript II (Invitrogen) and random hexamer primer. Rearrangement of RET/PTC 1 and 3 were determined by PCR amplification using specific primers of RET/PTC 1 and 3, respectively. In case of positive expression, RET/PTC rearrangements were confirmed with nested PCR using internal primer sets and analyzed with DNA sequencing. Results: The isolated total RNA quality was tested by amplification of glyceraldehydes 3 phosphate dehydrogenase. The RET/PTC 1 rearrangement was identified in 2 cases from 16 cases and also confirmed by DNA sequencing analysis. At present, we are analyzing the RET/PTC 3 rearrangement from samples. Conclusions: In this study, 12.5 % of RET/PTC 1 rearrangement was detected in 16 thyroid cancer tissue from Korea. The prevalence of RET/PTC rearrangement is an important genetic event underlying development of thyroid carcinomas.