BackgroundResveratrol, a herbal phytoalexin, is known to have anti-tumor effects in several tumors including thyroid cancer cells. AimThe aim of this study was to determine the effects of resveratrol on the expression of BRAF, ERK and NIS mRNA levels and protein expression in B-CPAP human thyroid papillary cancer cell line. MethodsB-CPAP cells were treated with resveratrol at concentrations of 10–100 μM for 24–48–72 h. Cell viability was assessed by XTT Cell Proliferation Assay. BRAF, ERK and NIS mRNA levels were evaluated by rt-PCR method. Protein expressions were evaluated by Western Blot method. ResultsResveratrol was found to inhibit cell proliferation in a time and dose dependent manner. The IC50 values of resveratrol were 18.7 μM and 56.8 μM after 48 h and 72 h respectively. Resveratrol treatment of B-CPAP cells resulted in up to 1.5-fold reduction in BRAF mRNA and up to 5.5 fold reduction in ERK mRNA levels. NIS mRNA levels showed up to 3-fold increase. Western Blot studies confirmed the rt- PCR results with a decrease in BRAF and ERK, and increase in NIS protein expressions. ConclusionThis study demonstrated that resveratrol inhibits thyroid papillary carcinoma cell proliferation and reduces poor prognostic BRAF and ERK mRNA and protein expressions, while increasing NIS mRNA and protein expression suggesting a redifferentiating effect. More studies are needed to evaluate resveratrol as a novel therapeutic agent in the treatment of papillary thyroid cancer.