Correlation of BRCA1 and APC aberrant methylation with the response to anthracycline-based neoadjuvant chemotherapy in primary breast cancer

Abstract

To investigate the correlation of hypermethylation of BRCA1 and APC gene promoters with the response to anthracycline-based neoadjuvant chemotherapy in primary breast cancer. One hundred and forty patients with primary breast cancer received anthracycline-based neoadjuvant chemotherapy, and pretreatment hypermethylation status of BRCA1 and APC genes promoters was detected by methylation-specific PCR. Of the 140 patients, 30 (21.4%) achieved pathological complete response (pCR), and methylation rates of BRCA1 and APC gene promoters were 21.4% (30/140) and 18.3% (24/131), respectively. Among the 110 patients with unmethylated BRCA1 gene, 28 (25.5%) achieved pCR, while in the 30 patients with methylated BRCA1 gene, only 2 (6.7%) had a pCR, with a significant difference between the two groups (chi(2) = 4.94, P = 0.026). However, no statistically significant correlation was found between the methylation of APC gene and pCR to neoadjuvant chemotherapy in this cohort of patients (P > 0.05). Primary breast cancer with an unmethylated BRCA1 gene is prone to achieve a pathological complete response to anthracycline-based neoadjuvant chemotherapy than those with a methylated BRCA1 gene. BRCA1 methylation status may be a useful predictor for anthracycline-based neoadjuvant chemotherapy in primary breast cancer patients.