Characterization of Vemurafenib-Resistant Melanoma Cell Lines

CELIA NOEMÍ PEREZ; LUDMILA E CAMPOS; CRISTIAN FALCON; CUELLO FEDERICO; SERGIO ALVAREZ

Congreso; Reunión Conjunta de Sociedades de Biociencias; 2019

SAIC

In recent years, the incidence of melanoma, the most aggressive skin cancer, has increased rapidly. Approximately half of melanoma patients have the V600E mutation in the BRAF protein, which stimulates ERK activation. In 2011, the FDA approved the use of Vemurafenib that reduces ERK activity by inhibiting BRAF. Unfortunately, the durability of the response is limited and the tumors quickly become resistant. Therefore, the objective of this work is to characterize a Vemurafenib-resistant Lu1205 melanoma cell line, obtained from its sensitive parental, which serves to study possible resistance mechanisms in tumor cells. Vemurafenib-resistant variants were derived from original parental cell line by continuous exposure to Vemurafenib to increasing concentrations (0,01µM ? 1µM) for 3 months. The proliferation rate was determined by the MTT assay; by Western Blot determined the levels of pERK and pAKT (from the PI3K pathway); Their migratory capacity was means in the Boyden chamber and their morphology was observed by inverted field microscope. We observed that the resistant cells presented a greater volume and prolongations and lamelipodia than their sensitive parents. Resistant cells cultured with Vemurafenib have a higher proliferation rate and their pERK levels are also higher, while pAKT levels remained similar. Finally, the resistant cells have a greater migratory capacity than their parents under normal culture conditions. These results suggest that the resistant cells obtained have a greater survival when grown with the inhibitor and have greater migratory capacity could have a greater metastatic capacity. In conclusion, the cells obtained from sensitive parents are more resistant to Vemurafenib, so they are a good model to study possible mechanisms involved in the development of resistance to BRAF inhibitors in the investigation of metastatic cutaneous melanoma