Annals of Oncology 25 (Supplement 4): iv255–iv279, 2014 doi:10.1093/annonc/mdu336.27
genitourinary tumours, prostate 779P
MICRORNAS EXPRESSION IN BLOOD ASSOCIATED WITH TAXANES RESPONSE AND OVERALL SURVIVAL IN METASTATIC CASTRATION-RESISTANT PROSTATE CANCER
M. Marín-Aguilera1, O. Reig2, G. Carrera3, L. Gaba Garcia2, N. Jiménez1, V. Pereira4, P. Gascon2, B. Mellado5 1 Translational Oncology Laboratory, Fundacio Clínic per a la Recerca Biomèdica, Barcelona, SPAIN 2 Medical Oncology, Hospital Clinic y Provincial de Barcelona, Barcelona, SPAIN 3 Medical Oncology, Hospital Plató, Barcelona, SPAIN 4 Medical Oncology, Hospital Clinic Barcelona, Barcelona, SPAIN 5 Oncology Department, Hospital Clínic de Barcelona, Barcelona, SPAIN
abstracts
Aim: MicroRNAs (miRs) are non-coding RNAs that regulate gene expression of several genes involved in cancer. Because their stability, these small molecules are potential to be blood-based markers for cancer diagnosis, staging, prognosis and response to treatment. The aim of this work was to analyze the prognostic and
predictive role of circulating miRs as potential biomarkers of metastatic castration-resistant prostate cancer (mCRPC). Methods: Peripheral blood from 87 mCRPC patients was collected. Fifty of them were obtained previously to chemotherapy treatment. The expression of 10 miRs selected from the literature as previously related to PC progression (miR21, miR34a, miR141, miR143, miR145, miR146a, miR205, miR221, miR222 and let7c) was analyzed at the mononuclear cells population by quantitative reverse transcriptase-polymerase chain reaction. Forty-three samples were analyzed in parallel for circulant tumor cells (CTC) count (CellSearch®). MiRs expression data were correlated with clinical characteristics, outcome, taxanes response and CTC count. Results: MiR143 and miR34a were significantly overexpressed in patients with ≥ 5 CTCs (n = 20) in comparison with those with < 5 CTCs (n = 23) (P < 0.001). Overexpression of let7c, miR34a, miR145, miR143 and miR21 in peripheral blood correlated with worse overall survival in mCRPC patients according to Kaplan-Meier analysis (P < 0.05). Non-responders to taxanes chemotherapy showed higher expression of miR146a and miR let7c (P < 0.05). Conclusions: This study suggests the utility of peripheral blood miRs detection as potential prognostic biomarker for mCRPC. Moreover, its association with chemotherapy response suggests a potential predictive value that needs to be further validated. Disclosure: All authors have declared no conflicts of interest.
© European Society for Medical Oncology 2014. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved. For permissions, please email:
[email protected].
