Microsatellite instability at a tetranucleotide repeat in type I endometrial carcinoma

• Published in: Journal of experimental & clinical cancer research 2008-12, Vol.27 (1), p.88-88, Article 88
• Main Authors: Choi, Yoo Duk, Choi, Jin, Kim, Jo Heon, Lee, Ji Shin, Lee, Jae Hyuk, Choi, Chan, Choi, Ho Sun, Lee, Min Cheol, Park, Chang Soo, Juhng, Sang Woo, Nam, Jong Hee
• Format: Article
• Language: English
• Subjects: Adaptor Proteins, Signal Transducing - biosynthesis; Adaptor Proteins, Signal Transducing - genetics; Adult; Aged; Care and treatment; DNA mismatch repair; DNA repair; Endometrial cancer; Endometrial Neoplasms - genetics; Endometrial Neoplasms - metabolism; Endometrial Neoplasms - pathology; Female; Genetic aspects; Health aspects; Humans; Immunohistochemistry; Microsatellite Instability; Microsatellite Repeats; Middle Aged; MutL Protein Homolog 1; MutS Homolog 2 Protein - biosynthesis; MutS Homolog 2 Protein - genetics; Nuclear Proteins - biosynthesis; Nuclear Proteins - genetics; Polymerase Chain Reaction; Risk factors; Trinucleotide repeats; Tumor Suppressor Protein p53 - biosynthesis; Tumor Suppressor Protein p53 - genetics
• ISSN: 1756-9966; 0392-9078; 1756-9966
• DOI: 10.1186/1756-9966-27-88

Microsatellite instability (MSI) at tri- or tetranucleotide repeat markers (elevated microsatellite alterations at selected tetranucleotide repeat, EMAST) has been recently described. But, the underlying genetic mechanism of EMAST is unclear. This study was to investigate the prevalence of EMAST, in type I endometrial carcinoma, and to determine the correlation between the MSI status and mismatch repair genes (MMR) or p53. We examined the 3 mono-, 3 di-, and 6 tetranucleotide repeat markers by PCR in 39 cases of type I endometrial carcinoma and performed the immunohistochemistry of hMSH2, hMLH1, and p53 protein. More than two MSI at mono- and dinucleotide repeat markers was noted in 8 cases (MSI-H, 20.5%). MSI, at a tetranucleotide repeat, was detected in 15 cases (EMAST, 38.5%). In remaining 16 cases, any MSI was not observed. (MSS, 42.1%), MSI status was not associated with FIGO stage, grade or depth of invasion. The absence of expression of either one of both hMSH2 or hMLH1 was noted in seven (87.5%) of eight MSI-H tumors, one (6.3%) of 16 MSS tumors, and five (33.3%) of 15 EMAST tumors. (p = 0.010) The expression of p53 protein was found in one (12.5%) of eight MSI-H tumors, five (31.3%) of 16 MSS tumors, and seven of 15 EMAST tumors. (p = 0.247) Our results showed that about 38.5% of type I endometrial carcinomas exhibited EMAST, and that EMAST was rarely associated with alteration of hMSH2 or hMLH1.