Preliminary study of microsatellite instability and loss of heterozygosity in thymic squamous cell carcinoma

Abstract

Objective To investigate the frequency of micresatellite instability (MSI) and loss of heterozygosity (LOH) and select sensitive loci for studying microsatellite DNA imbalance in thymic squamous cell carcinoma. Methods 5 microsat-ellitc polymorphism markers and extrated DNA were selected from 9 specmiens of paired thymie squamous cell carcinoma/nor-real tissues. MSI and LOH in the specmiens of thymic carcinoma and relevant pericancerou tissues were detected by polymerase chain reaction (PCR) followed by 6% polyacrylamide gel electrophoresis(PAGE) with silver staining. Results MSI or LOH was detected in 9 thymic carcinoma tissues. The frequency of MSI or LOH was 66.7% (6/9) at loci of D6S1708, 33.3% (3/9) at TP53, 33.3% (3/9)at DM, 33.3% (3/9)at D11S988 and 0% (0/9)at D8S136, LOH at D6S1708 (5/6) was a common genetic alteration. DI1S988 had only LOH alteration. Conclusion D6S1708, TP53, DM, and D11S988 are sensi-tive loci for studying microsatellite DNA imbalance in thymic squamous cell carcinoma. Microsatellite DNA imbalance may play a certain role in occurrence and development of thymic squamous cell carcinoma, and the relationship between MSi or LOH.The linicopathological features of thymic squamous cell carcinoma needs further investigation. Key words: Thymus neoplasms; Carcinoma squamous cell; Polymorphism; single nucleotide mierosateUite in-stability; Loss of heterozygosity