RESUMEN
BACKGROUND: Ataxia telangiectasia-mutated (ATM) gene downexpression has been reported in sporadic breast carcinomas (BC); however, the prognostic value and mechanisms of ATM deregulation remain unclear. PATIENTS AND METHODS: ATM and miRNAs (miR-26a, miR-26b, miR-203, miR-421, miR-664, miR-576-5p and miR-18a) expression levels were evaluated by quantitative real-time PCR (RT-qPCR) in 52 BC and 3 normal breast samples. ATM protein expression was assessed by immunohistochemistry in 968 BC and 35 adjacent normal breast tissues. ATM copy number alteration was detected by array comparative genomic hybridization (aCGH) in 42 tumours. RESULTS: Low ATM levels were associated with tumour grade. Absence of ATM protein expression was associated with distant metastasis (P < 0.001), reduced disease-free survival (DFS, P < 0.001) and cancer-specific survival (CSS, P < 0.001). Multivariate analysis indicated ATM protein expression as an independent prognostic marker for DFS (P = 0.001, HR = 0.579) and CSS (P = 0.001, HR = 0.554). ATM copy number loss was detected in 12% of tumours and associated with lower mRNA levels. miR-421 over-expression was detected in 36.5% of cases which exhibit lower ATM transcript levels (P = 0.075, r = -0.249). CONCLUSIONS: The data suggest that ATM protein expression is an independent prognostic marker in sporadic BC. Gene copy number loss and miR-421 over-expression may be involved in ATM deregulation in BC.
Asunto(s)
Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Proteínas de la Ataxia Telangiectasia Mutada/genética , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/mortalidad , Carcinoma Ductal de Mama/secundario , Estudios de Casos y Controles , Supervivencia sin Enfermedad , Regulación hacia Abajo , Femenino , Dosificación de Gen , Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Clasificación del Tumor , Pronóstico , Modelos de Riesgos ProporcionalesRESUMEN
BACKGROUND: The clinical relevance of transforming growth factor-beta (TGF-beta)-signalling pathway in breast carcinomas (BCs) remained elusive. This study aimed to evaluate the prognostic value of TGF-beta1 and transforming growth factor-beta type II receptor (TGF-betaRII) expression levels in tumour cells and their association with the established biomarkers in BC. PATIENTS AND METHODS: In 324 BC from patients with long-term follow-up, the TGF-beta1 and TGF-betaRII transcript and protein expression levels were assessed. RESULTS: TGF-beta1 and TGF-betaRII down-expression was significantly associated with BC. Negative TGF-beta1 and TGF-betaRII protein status was associated with the development of distant metastasis (P = 0.003 and P = 0.029, respectively). In multivariate analysis, TGF-beta1-positive tumours were associated with increased disease-free survival (DFS) [hazard ratio (HR) = 0.489, P = 0.003]. TGF-betaRII positivity was an independent prognostic factor for DFS (HR = 0.439, P = 0.001) and overall survival (OS) (HR = 0.409, P = 0.003) in human epidermal growth factor receptor-2 (HER2)-negative patients. Absence of TGF-beta1 and TGF-betaRII proteins in breast tumour cells was significantly associated with metastasis development. CONCLUSIONS: To the best of our knowledge, this is the first report indicating the relevance of HER2 status in discriminating TGF-betaRII as a prognostic marker for DFS and OS in human BC. These data indicate that TGF-betaRII protein analysis in tumour cells could be introduced in clinical practice as additional prognostic biomarker in HER2-negative BC.
Asunto(s)
Neoplasias de la Mama/diagnóstico , Carcinoma/diagnóstico , Genes erbB-2 , Proteínas Serina-Treonina Quinasas/genética , Receptores de Factores de Crecimiento Transformadores beta/genética , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/análisis , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/mortalidad , Carcinoma/genética , Carcinoma/metabolismo , Carcinoma/mortalidad , Regulación hacia Abajo , Femenino , Estudios de Seguimiento , Regulación Neoplásica de la Expresión Génica , Humanos , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Proteínas Serina-Treonina Quinasas/metabolismo , Receptor Tipo II de Factor de Crecimiento Transformador beta , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Análisis de Supervivencia , Factor de Crecimiento Transformador beta1/genética , Adulto JovenRESUMEN
Clinical stage (CS) is an established indicator of breast cancer outcome. In the present study, a cDNA microarray platform containing 692 genes was used to identify molecular differences between CSII and CSIII disease. Tumor samples were collected from patients with CSII or CSIII breast cancer, and normal breast tissue was collected from women without invasive cancer. Seventy-eight genes were deregulated in CSIII tumors and 22 in CSII tumors when compared to normal tissue, and 20 of them were differentially expressed in both CSII and CSIII tumors. In addition, 58 genes were specifically altered in CSIII and expression of 6 of them was tested by real time RT-PCR in another cohort of patients with CSII or CSIII breast cancer and in women without cancer. Among these genes, MAX, KRT15 and S100A14, but not APOBEC3G or KRT19, were differentially expressed on both CSIII and CSII tumors as compared to normal tissue. Increased HMOX1 levels were detected only in CSIII tumors and may represent a molecular marker of this stage. A clear difference in gene expression pattern occurs at the normal-to-cancer transition; however, most of the differentially expressed genes are deregulated in tumors of both CS (II and III) compared to normal breast tissue.
Asunto(s)
Neoplasias de la Mama/genética , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica/genética , Adulto , Anciano , Antibióticos Antineoplásicos/uso terapéutico , Secuencia de Bases , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Doxorrubicina/uso terapéutico , Femenino , Humanos , Persona de Mediana Edad , Datos de Secuencia Molecular , Estadificación de Neoplasias , Análisis de Secuencia por Matrices de Oligonucleótidos , Estudios Prospectivos , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
Clinical stage (CS) is an established indicator of breast cancer outcome. In the present study, a cDNA microarray platform containing 692 genes was used to identify molecular differences between CSII and CSIII disease. Tumor samples were collected from patients with CSII or CSIII breast cancer, and normal breast tissue was collected from women without invasive cancer. Seventy-eight genes were deregulated in CSIII tumors and 22 in CSII tumors when compared to normal tissue, and 20 of them were differentially expressed in both CSII and CSIII tumors. In addition, 58 genes were specifically altered in CSIII and expression of 6 of them was tested by real time RT-PCR in another cohort of patients with CSII or CSIII breast cancer and in women without cancer. Among these genes, MAX, KRT15 and S100A14, but not APOBEC3G or KRT19, were differentially expressed on both CSIII and CSII tumors as compared to normal tissue. Increased HMOX1 levels were detected only in CSIII tumors and may represent a molecular marker of this stage. A clear difference in gene expression pattern occurs at the normal-to-cancer transition; however, most of the differentially expressed genes are deregulated in tumors of both CS (II and III) compared to normal breast tissue.