MAPK pathway and NIS in B-CPAP human papillary thyroid carcinoma cells treated with resveratrol.

Background: Resveratrol, a herbal phytoalexin, is known to have anti-tumor effects in several tumors including thyroid cancer cells.

Aim: The 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.

Methods: B-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.

Results: Resveratrol 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.

Conclusion: This 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.