Evaluation of response to tyrosine kinase inhibitors in renal cell carcinoma patients based on expression of miR-99b, -144, -210, -222, -302а and -377 in tumor tissue.

Background: Renal cell carcinoma (RCC) is one of the most common solid tumors in adults highly resistant to conventional therapies. The expression profile of a number of miRNAs correlates with RCC response to chemotherapeutic agents.

Aim: To identify the association of tumor miRNAs expression with neoadjuvant treatment response in patients with RCC.

Materials And Methods: We analyzed the expression levels of tumor miR-99b, -144, -155, -210, -222, -302а, -377 in 93 RCC patients who received pazopanib or sunitinib in neoadjuvant regimen using RT-PCR. RNU48 was used as a reference miRNA.

Results: The levels of expression of miR-99b and -377 are associated with the RCC response to pazopanib, and microRNA-210 and -377 to sunitinib. The characteristic expression profile of miR-99b, -144, -222, -377, and miR-302a determined in 90% of cases was delineated in pazopanib responders as opposed to nonresponders. Similarly, the characteristic expression profile of miR-210, -222, -302a and -377 was suggested for sunitinib responders.

Conclusions: Levels of miR-99b, -210 and -377 expression in RCC tumor tissue might be used as a basis for future predictive panel intended for the assessment of the sensitivity to the regimens of neoadjuvant RCC treatment.