RESUMEN
lncRNAs are noncoding transcripts with tissue and cancer specificity. Particularly, in breast cancer, lncRNAs exhibit subtype-specific expression; they are particularly upregulated in luminal tumors. However, no gene signature-based laboratory tests have been developed for luminal breast cancer identification or the differential diagnosis of luminal tumors, since no luminal A- or B-specific genes have been identified. Particularly, luminal B patients are of clinical interest, since they have the most variable response to neoadjuvant treatment; thus, it is necessary to develop diagnostic and predictive biomarkers for these patients to optimize treatment decision-making and improve treatment quality. In this study, we analyzed the lncRNA expression profiles of breast cancer cell lines and patient tumor samples from RNA-Seq data to identify an lncRNA signature specific for luminal phenotypes. We identified an lncRNA signature consisting of LINC01016, GATA3-AS1, MAPT-IT1, and DSCAM-AS1 that exhibits luminal subtype-specific expression; among these lncRNAs, GATA3-AS1 is associated with the presence of residual disease (Wilcoxon test, p < 0.05), which is related to neoadjuvant chemotherapy resistance in luminal B breast cancer patients. Furthermore, analysis of GATA3-AS1 expression using RNA in situ hybridization (RNA ISH) demonstrated that this lncRNA is detectable in histological slides. Similar to estrogen receptors and Ki67, both commonly detected biomarkers, GATA3-AS1 proves to be a suitable predictive biomarker for clinical application in breast cancer laboratory tests.
Asunto(s)
Biomarcadores de Tumor , Neoplasias de la Mama , Resistencia a Antineoplásicos , Regulación Neoplásica de la Expresión Génica , Terapia Neoadyuvante , ARN Largo no Codificante , Humanos , ARN Largo no Codificante/genética , Neoplasias de la Mama/genética , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Neoplasias de la Mama/metabolismo , Femenino , Resistencia a Antineoplásicos/genética , Biomarcadores de Tumor/genética , Línea Celular Tumoral , Perfilación de la Expresión Génica , Factor de Transcripción GATA3/genética , Factor de Transcripción GATA3/metabolismo , TranscriptomaRESUMEN
Given their tumor-specific and stage-specific gene expression, long non-coding RNAs (lncRNAs) have demonstrated to be potential molecular biomarkers for diagnosis, prognosis, and treatment response. Particularly, the lncRNAs DSCAM-AS1 and GATA3-AS1 serve as examples of this because of their high subtype-specific expression profile in luminal B-like breast cancer. This makes them candidates to use as molecular biomarkers in clinical practice. However, lncRNA studies in breast cancer are limited in sample size and are restricted to the determination of their biological function, which represents an obstacle for its inclusion as molecular biomarkers of clinical utility. Nevertheless, due to their expression specificity among diseases, such as cancer, and their stability in body fluids, lncRNAs are promising molecular biomarkers that could improve the reliability, sensitivity, and specificity of molecular techniques used in clinical diagnosis. The development of lncRNA-based diagnostics and lncRNA-based therapeutics will be useful in routine medical practice to improve patient clinical management and quality of life.
Asunto(s)
Neoplasias de la Mama , ARN Largo no Codificante , Humanos , Femenino , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Calidad de Vida , Reproducibilidad de los Resultados , Biomarcadores , Biomarcadores de Tumor/genética , Regulación Neoplásica de la Expresión GénicaRESUMEN
Although breast conserving surgery is the standard of care for patients with localized breast cancer in high-income countries, little is known about its use in developing countries, where disparities in access to treatment may lead to an increased use of mastectomy. We examined the use of breast conserving surgery at a Mexican cancer center after the implementation of a public insurance program aimed at providing coverage for previously uninsured patients. Between 2006 and 2016, 4519 women received surgical treatment for breast cancer, of which 39% had early-stage disease. The proportion of patients treated with breast conserving surgery increased from 10% in the 2006-2009 period to 33% in the 2013-2016 period, with most of this increase occurring among women with early-stage disease (17-52%). Improving access to care and reducing the financial burden of breast cancer in developing countries may lead to an increased use of breast conserving surgery.