RESUMO
PURPOSE: RACGAP1 is a Rac GTPase-activating protein involved in cell growth regulation, cell transformation and metastasis. The aim of the present study was to explore the prognostic and/or predictive significance of RACGAP1 mRNA expression on disease-free survival (DFS) and overall survival (OS) in high-risk early breast cancer patients and compare it to that of Ki67 protein expression and to the Nottingham prognostic index (NPI). METHODS: A total of 595 high-risk breast cancer patients were treated in a two-arm trial evaluating postoperative dose-dense sequential chemotherapy with epirubicin followed by CMF with or without paclitaxel. RNA was extracted from 314 formalin-fixed paraffin-embedded primary tumor tissue samples followed by one-step quantitative RT-PCR for assessing RACGAP1 mRNA expression. RESULTS: High RACGAP1 mRNA expression (above the median) was associated with poor DFS (log-rank, p = 0.002) and OS (p < 0.001). High histological grade, as well as high Ki67 protein expression, was more frequent in the high-expression group of RACGAP1. Results of the Cox multivariate regression analysis revealed that high RACGAP1 mRNA expression independently predicted poor overall survival (Wald's p = 0.008). High Ki67 protein expression was also an adverse prognostic factor for death (p = 0.016), while high NPI score values were not. CONCLUSIONS: High RACGAP1 mRNA expression, as assessed by qRT-PCR, was found to be of adverse prognostic significance in high-risk early breast cancer patients treated with dose-dense sequential chemotherapy. The utility of RACGAP1 mRNA expression in patient selection for treatment with aggressive chemotherapy regimens should be further explored and validated in larger cohorts.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias da Mama/tratamento farmacológico , Proteínas Ativadoras de GTPase/genética , Regulação Neoplásica da Expressão Gênica , Antígeno Ki-67/genética , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Intervalo Livre de Doença , Feminino , Humanos , Pessoa de Meia-Idade , Análise Multivariada , Seleção de Pacientes , Prognóstico , Modelos de Riscos Proporcionais , RNA Mensageiro/metabolismo , Ensaios Clínicos Controlados Aleatórios como Assunto , Análise de Regressão , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida , Adulto JovemRESUMO
OBJECTIVE: Early-stage epithelial ovarian cancer represents a prognostically heterogenous group. We studied prognostic factors in patients treated with adjuvant paclitaxel/carboplatin chemotherapy. METHODS: Data was extracted from 147 patients with FIGO stage IA/IB, grade 2/3 or stage IC/IIA (any grade) who underwent primary surgery followed by paclitaxel/carboplatin chemotherapy. RESULTS: Median follow-up was 88 months. Ten-year relapse-free (RFS) and disease-specific survival (DSS) were: 81% (95% confidence interval [CI]: 73-89) and 81% (95% CI: 73-89). On multivariate analysis, non serous histology was associated with reduced risk for RFS (0.294, 95% CI: 0.112-0.577, p=0.001) and DSS (0.194, 95% CI: 0.075-0.504, p=0.001), while high-risk category (stage IC/IIA and grade 2/3) with increased risk for RFS (3.989, 95% CI: 1.189-13.389, p=0.009) and DSS (3.989, 95% CI: 1.064-16.386, p=0.038). The combination of histology and grade identified 3 groups with distinctly different 10-year RFS and DSS rates (p<0.001): grade 1 (100% and 100%), non-serous grade 2/3 (83% and 86%) and serous grade 2/3 (60% and 60%). CONCLUSIONS: Serous histology is an adverse prognostic factor in early-stage ovarian cancer treated with adjuvant paclitaxel/carboplatin. Risk stratification according to histology and grade is a useful discriminator of prognosis and can be used in the design of future studies.
