Abstract 1172: RARB is a biomarker of poor prognosis in prostate carcinomas

• Published in: Cancer research (Chicago, Ill.) Ill.), 2010-04, Vol.70 (8_Supplement), p.1172-1172
• Main Authors: Alves, Flavia C M C, Drigo, Sandra A., Rainho, Cláudia A., Camargo, João L V, Fonseca, Francisco P., Soares, Fernando A., Trindade-Filho, José C S, Domingues, Maria A C, Rogatto, Silvia R.
• Format: Article
• Language: English
• ISSN: 0008-5472; 1538-7445
• DOI: 10.1158/1538-7445.AM10-1172

Purpose: Despite the advances in prostate carcinomas (PCa) management, about 30% of the patients who undergo radical prostatectomy presented biochemical recurrence (BCR). BCR is considered an unfavorable prognostic factor followed by clinical disease progression. The current prognostic markers in PCa are unable detect correctly who is at risk for BCR. Hypermethylation at RARB and RASSF1A genes have been associated with worse prognosis in PCa. The current study aimed to evaluate RARB, and RASSF1A hypermethylation frequencies in prostate carcinoma (PCa) and to correlate these alterations with down-regulation at transcriptional and protein levels and with clinical outcome. Methods: Methylation patterns of RARB and RASSF1A were determined by methylation-specific PCR in 68 PCa samples and 27 non-neoplastic prostate tissues. Gene expression was evaluated by quantitative RT-PCR in 73 PCa, 15 adjacent non-neoplastic prostate tissues (AdjP) and two normal prostate (N). Protein expression was evaluated in an independent PCa cohort (n=141) with long-term follow-up period. The findings were associated with clinicopathological parameters and BCR-free survival (BRFS). Results: RARB and RASSF1A genes were hypermethylated in PCa (P