RESUMEN
BACKGROUND: Molecular characterization of tumors could be a key to therapeutic decision-making with regards to targeted therapies in castration-resistant prostate cancer (CRPC). A convenient solution may be non-invasive liquid biopsy testing of circulating tumor cells (CTCs). For this reason, CTC-enriched samples obtained by immunomagnetic separation (AdnaTest®) were studied as a source material for high-throughput gene expression analysis using BioMark™. PATIENTS AND METHODS: CTC-enriched samples from 41 CRPC patients previously determined to be CTC positive using the AdnaTest® were retrospectively re-analysed for androgen receptor (AR) messenger RNA (mRNA), using the updated AdnaTest®. Blood samples were drawn two times from each patient: at the time of CRPC diagnosis and after the third docetaxel cycle. A gene expression panel of 27 genes related to CRPC therapeutic decision-making, including AR full length (ARFL) and splice variant 7 (ARV7), was retrospectively analyzed on a BioMark™ platform in 29 of 41 patients. RESULTS: The AdnaTest® detected AR mRNA in three-quarters of CTC-positive samples taken at the time of CRPC diagnosis and after the third docetaxel cycle. AR detection was associated with a shorter disease-specific survival (45.0 vs. 20.4 months) at the time of CRPC diagnosis. ARFL expression at the time of CRPC diagnosis, measured on the BioMark™ platform, was associated with a lower decrease of serum level of prostate-specific antigen (sPSA) (p = 0.029), i.e., worse therapy response. ARV7 was found in 38% of the ARFL--positive samples at both analyzed timepoints. CONCLUSION: Detection of AR expression by AdnaTest® in CTC-enriched samples may help predict patients' survival. These AdnaTest® CTC-enriched samples can be used in a high-throughput quantitative polymerase chain reaction (qPCR) analysis of gene expression, provided that the specificity of the assay for each individual gene is properly validated. The BioMark™ platform can be used for the simultaneous detection of ARFL and ARV7 and other genes in CTC-enriched samples from CRPC patients.
Asunto(s)
Biomarcadores de Tumor , Perfilación de la Expresión Génica , Células Neoplásicas Circulantes/metabolismo , Neoplasias de la Próstata Resistentes a la Castración/diagnóstico , Neoplasias de la Próstata Resistentes a la Castración/genética , Anciano , Anciano de 80 o más Años , Estudios de Seguimiento , Perfilación de la Expresión Génica/métodos , Pruebas Genéticas/métodos , Ensayos Analíticos de Alto Rendimiento , Humanos , Separación Inmunomagnética , Masculino , Persona de Mediana Edad , Células Neoplásicas Circulantes/patología , Reacción en Cadena en Tiempo Real de la Polimerasa , TranscriptomaRESUMEN
BACKGROUND: Detection of circulating tumor cells (CTC) in patients with castration-resistant prostate cancer (CRPC) may improve the estimate of chemotherapy response. We evaluated the AdnaTest® system in patients receiving docetaxel. PATIENTS AND METHODS: CTC analysis was carried out in 37 patients by immunomagnetic separation. Correlation between serum prostate-specific antigen (sPSA) change and CTC presence and the influence of each parameter on the overall survival (OS) were evaluated. RESULTS: We detected CTCs in 32 and 16 patients before and after three docetaxel cycles, respectively. The sPSA level correlated with CTC positivity during docetaxel therapy (p=0.0031). The longest OS was in patients negative for CTCs in both samples (p=0.0228). Change in sPSA levels was associated with treatment response (p=0.033). CONCLUSION: We detected CTCs in a considerable number of patients with CRPC. The absolute change of sPSA level correlated with OS. CTC presence during docetaxel therapy was associated with shorter OS.
Asunto(s)
Células Neoplásicas Circulantes , Neoplasias de la Próstata Resistentes a la Castración/sangre , Anciano , Anciano de 80 o más Años , Antineoplásicos/uso terapéutico , Docetaxel , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Pronóstico , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata Resistentes a la Castración/patología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Taxoides/uso terapéutico , Resultado del TratamientoRESUMEN
Prostate cancer (PC) is the most common malignant disease in men. Prognosis of patients with metastatic PC is generally unfavourable; however there are significant differences in survival at this stage of the disease. The definition of prognosis is essential for the selection of therapy, respecting an individual risk. In recent years, the association between circulating tumor cells (CTC) detection and response to PC treatment has been widely investigated. Detection of CTC is based on a metastatic process theory and uses well-known tumor-specific antigens on the cell surface. Individual methods assess CTC with different sensitivity and are not yet efficient at the localised PC stage. Only the method of immunomagnetic separation and semi-automatic visualisation (CellSearchTM) has been validated and approved for the use in the PC management. Assessment of the CTC count directly correlates with the prognosis of patients with castration-resistant PC. Change in the CTC count during the therapy also considerably improves risk estimation and represents a marker of overall survival. New methods of CTC cultivation and gene profiling may contribute to individualisation of the treatment similarly to breast cancer. The authors present a review article about theory, methods of detection and clinical use of CTC in castration-resistant PC.
