Fig. 2

miR-146a regulates NFkB-related signaling pathways associated with resistance and directly targets PTGS2. a Immunoblot showing reduced levels of NFkB, AKT, p70S6K, and ERK in melanoma cells transfected with synthetic miR-146a (m-miR-146a) compared to mimic negative control transfectants (left). Reduction of phosphorylated proteins in miR-146a transfectants calculated by signal quantification (right). b Reduced expression of miR-146a target genes in transfectants (m-miR-146a: miR-146a mimic; S: mimic scrambled control). c Expression levels of PTGS2 and PTGES genes in resistant cell lines (R) compared to their sensitive counterparts (S). d Positive correlation between PTGS2 expression and IC50 values of BRAF/MEKi in melanoma cell lines (Spearman analysis). e Higher levels of COX2 protein expression in resistant cells (R) compared to their sensitive counterparts (S). Specific signals were quantified and expressed as the ratio of COX2/actin intensity. f Reduction of COX2 protein expression in LM16R resistant cells transfected with miR-146a mimic (m-miR-146a) and increased levels in LM36 parental sensitive cells transfected with miR-146a inhibitor (i-miR-146a). Changes in COX2 expression were calculated by signal quantification. P values were calculated by Student’s unpaired t test in A and F, and by Mann-Whitney U test in B. _*: p < 0.05, _**: p < 0.01, _***: p < 0.0001