RESUMEN
BACKGROUND: The HER2 gene has been established as a valid biological marker for the treatment of breast cancer patients with trastuzumab and probably other agents, such as paclitaxel and anthracyclines. The TOP2A gene has been associated with response to anthracyclines. Limited information exists on the relationship of HER2/TOP2A gene status in the presence of centromere 17 (CEP17) gain with outcome of patients treated with anthracycline-containing adjuvant chemotherapy. METHODS: Formalin-fixed paraffin-embedded tumor tissue samples from 1031 patients with high-risk operable breast cancer, enrolled in two consecutive phase III trials, were assessed in a central laboratory by fluorescence in situ hybridization for HER2/TOP2A gene amplification and CEP17 gain (CEP17 probe). Amplification of HER2 and TOP2A were defined as a gene/CEP17 ratio of >2.2 and ≥2.0, respectively, or gene copy number higher than 6. Additionally, HER2, TopoIIa, ER/PgR and Ki67 protein expression was assessed by immunohistochemistry (IHC) and patients were classified according to their IHC phenotype. Treatment consisted of epirubicin-based adjuvant chemotherapy followed by hormonal therapy and radiation, as indicated. RESULTS: HER2 amplification was found in 23.7% of the patients and TOP2A amplification in 10.1%. In total, 41.8% of HER2-amplified tumors demonstrated TOP2A co-amplification. The median (range) of HER2, TOP2A and CEP17 gain was 2.55 (0.70-45.15), 2.20 (0.70-26.15) and 2.00 (0.70-26.55), respectively. Forty percent of the tumors had CEP17 gain (51% of those with HER2 amplification). Adjusting for treatment groups in the Cox model, HER2 amplification, TOP2A amplification, CEP17 gain and HER2/TOP2A co-amplification were not associated with time to relapse or time to death. CONCLUSION: HER2 amplification, TOP2A amplification, CEP17 gain and HER2/TOP2A co-amplification were not associated with outcome in high-risk breast cancer patients treated with anthracycline-based adjuvant chemotherapy. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry (ANZCTR) ACTRN12611000506998 and ACTRN12609001036202.
Asunto(s)
Antígenos de Neoplasias/genética , Neoplasias de la Mama/genética , ADN-Topoisomerasas de Tipo II/genética , Proteínas de Unión al ADN/genética , Receptor ErbB-2/genética , Adulto , Anciano , Antraciclinas/administración & dosificación , Antígenos de Neoplasias/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Centrómero , Aberraciones Cromosómicas , Cromosomas Humanos Par 17 , Ensayos Clínicos Fase III como Asunto , ADN-Topoisomerasas de Tipo II/metabolismo , Proteínas de Unión al ADN/metabolismo , Femenino , Dosificación de Gen , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Oportunidad Relativa , Proteínas de Unión a Poli-ADP-Ribosa , Pronóstico , Ensayos Clínicos Controlados Aleatorios como Asunto , Receptor ErbB-2/metabolismo , Adulto JovenRESUMEN
BACKGROUND: BRCA1 (B), ERCC1 (E), RRM1 (R) and TYMS (T) mRNA expression has been extensively studied with respect to NSCLC patient outcome upon various chemotherapy agents. However, these markers have not been introduced into clinical practice yet. One of the reasons seems to be lack of a standard approach for the classification of the reported high/low mRNA expression. The aim of this study was to determine the prognostic/predictive impact of B, E, R, T in routinely-treated NSCLC patients by taking into account the expression of these genes in the normal lung parenchyma. METHODS: B, E, R, T mRNA expression was examined in 276 NSCLC samples (real-time PCR). The normal range of B, E, R, T transcript levels was first determined in matched tumor - normal pairs and then applied to the entire tumor series. Four main chemotherapy categories were examined: taxanes-without-platinum (Tax); platinum-without-taxanes (Plat); taxanes/platinum doublets (Tax/Plat); and, all-other combinations. RESULTS: In comparison to remotely located normal lung parenchyma, B, E, R, T mRNA expression was generally increased in matched tumors, as well as in the entire tumor series. Therefore, tumors were classified as expressing normal or aberrant B, E, R, T mRNA. In general, no marker was associated with overall and progression free survival (OS, PFS). Upon multivariate analysis, aberrant intratumoral TYMS predicted for shorter PFS than normal TYMS in 1st line chemo-naïve treated patients (p = 0.012). In the same setting, specific interactions were observed for aberrant TYMS with Plat and Tax/Plat (p = 0.003 and p = 0.006, respectively). Corresponding patients had longer PFS in comparison to those treated with Tax (Plat: HR = 0.234, 95% CI:0.108-0.506, Wald's p < 0.0001; Tax/Plat: HR = 0.242, 95% CI:0.131-0.447, Wald's p < 0.0001). Similar results were obtained for PFS in 1st line chemo-naïve and (neo)adjuvant pre-treated patients. Adenocarcinoma, early disease stage, and treatment with Tax/Plat doublets independently predicted for prolonged OS in patients who received only one line of treatment (adjuvant or 1st line). CONCLUSION: Classifying intratumoral B, E, R, T mRNA expression in comparison to normal lung may facilitate standardization of these parameters for prospective studies. With this approach, NSCLC patients with aberrant intratumoral TYMS expression will probably fare better with platinum-based treatments.