Multidrug resistance (MDR) is one of the most important mechanisms involved in chemotherapy failure in cancer. ABC transporters constitute a superfamily of pumps that efflux metabolites, xenobiotics and drugs outside the cell. In many types of malignant tumors some of these transporters are overexpressed causing MDR and consequently tumor progression. ABCB1, ABCC1 and ABCG2 are the ABC transporters whose overexpressions are most frequently involved in chemotherapy failure. Eventhough expression of these transporters has been well studied in many types of adult tumors, expression of ABC transporters and correlation with clinical features have been scarcely reported in retinoblastoma, and intraocular malignant tumor occurring in early infancy. Therefore our objective in this work was to determine ABCB1, ABCC1 and ABCG2 expression by qPCR in untreated primary retinoblastoma cases and to explore whether or not correlations with relevant clinical features do exist. Our results on RNA from 40 retinoblastoma cases naive to chemotherapy treatment, show high mRNA expression of ABCC1 followed by ABCB1 and marginal expression of ABCG2, these results are consistent with immunohistochemistry results from others. ABCC1 was found significantly more expressed in bilateral than unilateral cases.

Citation Format: Blanca Elena Castro, Eunice Aguilar, Lourdes Cabrera, Javier Camacho, Adriana Hernandez, Guillermo Ramón, Stanislaw Sadowinski, Manuela Orjuela, Veronica Ponce. Analysis of ABCB1, ABCC1 and ABCG2 expression and clinical parameters in 40 primary retinoblastoma cases. [abstract]. In: Proceedings of the AACR Precision Medicine Series: Drug Sensitivity and Resistance: Improving Cancer Therapy; Jun 18-21, 2014; Orlando, FL. Philadelphia (PA): AACR; Clin Cancer Res 2015;21(4 Suppl): Abstract nr A26.

©2015 American Association for Cancer Research.
2015