VRK2 silencing decreased COX-2 mRNA levels and COX-2 expression.
A, total RNA from MDA-MB-231 breast cancer cells transfected with control siRNA (siC) or VRK2-specific siRNA (siVRK2-06) and stimulated or not with 100 ng/μl PMA and 0.5 μm Io was used for quantitative RT-PCR analysis to measure COX-2 and VRK2 mRNA levels. Data were normalized with glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA levels, and results are the mean of three independent experiments. **, p < 0.005; ***, p < 0.0005. B, total RNA from MDA-MB-435 melanoma cells treated as in A. ***, p < 0.0005. C, VRK2 knockdown by specific siRNA transfection did not affect NFAT1 mRNA levels in MDA-MB-435 and MDA-MB-231 cell lines. D, COX-2 protein expression decreased in MDA-MB-231 cells with reduced VRK2 protein levels. NFAT1 protein levels were not affected by VRK2 silencing. At the right is shown the quantification of protein levels. Error bars, S.D.