Studies on CYP1A1, CYP1B1 and CYP3A4 gene polymorphisms in breast cancer patients

Abstract

Abstract Background: The role of CYP1A1, CYP1B1 and CYP3A4 polymorphism in pathogenesis of breast cancer has not been fully elucidated. From three CYP1A1 polymorphisms *2A (3801T>C), *2C (2455A>G), and *2B variant, which harbors both polymorphisms, the *2A variant is potentially carcinogenic in African Americans and the Taiwanese, but not in Caucasians, and the CYP1B1*2 (355G>T) and CYP1B1*3 (4326C>G) variants might increase breast cancer risk. Although no association of any CYP3A4 polymorphisms and breast cancer has been documented, the CYP3A4*1B (392A>G) variant, correlates with earlier menarche and endometrial cancer secondary to tamoxifen therapy. Objective: The present study was designed to investigate the frequency of CYP1A1, CYP1B1 and CYP3A4 polymorphisms in a sample of breast cancer patients from the Polish population and to correlate the results with the clinical and laboratory findings. Material and methods: The frequencies of CYP1A1*2A; CYP1A1*2C; CYP1B1*3; CYP3A4*1B CYP3A4*2 polymorphisms were determined in 71 patients aged 36-87, with primary breast cancer and 100 healthy individuals. Genomic DNA was extracted from the tumor, and individual gene fragments were PCR-amplified. The polymorphisms were determined by RFLP and were correlated with the patients’ TNM stage, grade, estrogen and progesterone receptor status as well as the level of c-erbB-2 protein. Results: CYP1A1 polymorphisms were more frequent in younger patients and in the patients with high level of c erbB 2 protein. No correlation between these polymorphisms and the cancer stage or grade, as well as the receptor status was demonstrated. Conclusions: CYP1A1 polymorphisms probably predispose to an earlier onset of breast cancer and might be associated with higher c-erbB-2 protein level, but further studies on a much larger group are required to substantiate our findings.