[Expression of estrogen sulfotransferase (EST) gene and bridging integrator protein-1 (BIN1) gene and their significance in breast tissues].

BACKGROUND & OBJECTIVE: Estrogen sulfotransferase (EST) is an enzyme which metabolizes estrogen into inactive estrogen sulphate. Bridging integrator protein-1 (BIN1) is a novel c-myc-interacting protein with the features of tumor suppressor. EST and BIN1 may be protective in tumorigenesis. This study was to detect the gene expression of EST and BIN1 in breast cancer tissues,and further investigate the carcinogenesis mechanism of breast cancer.

METHODS

The mRNA levels of EST and BIN1 in 12 specimens of normal human breast tissue, and 24 specimens of breast cancer were measured by reverse transcriptase-polymerase chain reaction (RT-PCR).

RESULTS

EST mRNA and BIN1 mRNA were expressed in all normal human breast tissues, while EST mRNA was decreased in 75.0% (18/24), and lost in 25.0% (6/24) breast cancer specimens; BIN1 mRNA was decreased in 25.0%(16/24), and lost in 66.7.0% (16/24) breast cancer specimens.

CONCLUSION

Down-regulation of EST mRNA and BIN1 mRNA may play an important role in the molecular mechanisms of breast carcinogenesis.