Promoter methylation of p16INK4A, RASSF1A, and RAR2b genes in tumor DNA from patients with breast cancer (BC) in correlation with clinical recurrence.

1551 Background: Currently, no definite epigenetic markers exist to predict tumor recurrence after surgical resection in patients (pts) with BC. We studied the methylation pattern of 3 growth regulatory genes p16INK4A , RASSF1A and RAR2b in pts with BC to determine if this process is associated with an increased recurrence risk. Methods: Genomic DNA from paraffin-embedded tissue specimens extracted from 74 pts with Breast Lesions (BL), who underwent surgical excision between 2003- 2005. DNA methylation was determined by chemical modification of DNA and subsequent double “hot start” methylation-specific PCR (MSP), followed by capillary-array electrophoresis analysis. The median follow-up of pts was 54 months. Results: 52/74 pts had BC and 22 benign lesions. Methylation of p16INK4A was observed in 20/52 (38.4%) and in 2/22 (9%), of RASSF1A in 30/52 (57.7%) and in 10/22 (45.4%), of RAR 2b in 22/52 (42.3%) and in 14/22(63.6%) of pts respectively. Both p16INK4A and RASSF1A were methylated in 10/52 and 0/22, p1...