MEX3A promotes resistance to gemcitabine in PDAC cells. (A, B) Analyses of MEX3A expression in PDAC cells by qPCR (A) and western blot (B). Data were normalized for L34 (A) and GAPDH (B) expression. (C) Percentage of survival evaluated by MTS assay after 72 h of treatment with two doses of gemcitabine (0.6 and 1 μm) in PDAC cells. Statistical analyses are reported in light blue when is referred to HPAF cells, while in blue when is referred at ASPC1 cells. (D, E) Analyses of MEX3A expression by qRT‐PCR (D) and western blot (E) to evaluate depletion of the transcript and protein after silencing with siMEX3A‐1 or smartpool (sp) siRNAs. (F) Percentage of survival evaluated by MTS assay after 72 h of treatment with the indicated doses of gemcitabine in MiaPaCa‐2 cells transfected with CTRL, MEX3A‐1 or MEX3A‐sp siRNAs. (G) Clonogenic assay to evaluate survival of the parental and drug‐resistant (MP‐DR) MiaPaCa‐2 cells in the presence of the indicated doses of gemcitabine. (H) Western blot of MEX3A expression in MP‐2‐DR and parental MiaPaCa‐2 cells. Statistical analyses were performed by one‐way ANOVA (A, D, G) and two‐way ANOVA (C, F). *P ≤ 0.05, **P ≤ 0.01, ***P ≤ 0.001.