The Expression of High Mobility Group I (Y) Proteins in Human Breast Cancer

ABSTRACT

PURPOSE: The precise mechanisms of tumorigenesis of breast cancer remains unknown in spite of major efforts. Recent studies have shown that High Mobility Group I (Y) Proteins [HMGI(Y)] have an important role in the regulation of chromatin structure and function, and that HMGI(Y) protein expression is generally correlated with a malignant phenotype. This study was undertaken to define the relationship of the HMGI(Y) protein expression between malignant breast tissue and non-malignant breast tissue in human, and clinico- pathologic findings were reviewed for this purpose. METHODS: Using Reverse Transcription-Polymerase Chain Reaction (RT-PCR) for HMGI(Y) with beta-actin, this study demonstrated the expression of HMGI(Y). The p53, ER, and PR. were defined by immunohistochemical staining. RESULTS: The HMGI(Y) expression was increased in the malignant tissue (90%), than in benign (76.9%) or normal (65%) tissue (p=0.031). As for the invasive ductal cancers, there was no difference between the HMGI(Y) expression and histopathologic parameters. CONCLUSION: These results suggest that the HMGI(Y) expression may be of little pathogenetic prognostic importance in human breast cancer.