Isothiouronium Salts Reduce NRAS Expression, Induce Apoptosis and Decrease Invasion of Melanoma Cells

Abstract

Melanoma is a very aggressive type of skin cancer. Mutation in BRAF and NRAS are often found in patients with this disease. Therefore, in recent years the search for new molecules that inhibit these proteins has been intensified. After many years with no new treatments for melanoma, the U.S. Food and Drug Administration (FDA) recently approved vemurafenib. However, many patients have already acquired resistance and have experienced severe side effects. Therefore, this work aims to evaluate a new set of compounds including allylic isothiouronium salts (1, 2 and 3), N-phenyl-substituted analog (4) and isothiosemicarbazide salts (5 and 6) for their potential antimelanoma activity. To this end, viability assay, cell cycle analysis, expression of NRAS and BRAF, as well as migration and invasion assay were performed with different melanoma cell lines. Isothiouronium salts 1-3 presented CC50 (concentration required to reduce the cell number by 50%) in a range of 7-28 μM. Furthermore, salt 1 significantly decreased the expression of NRAS. However, cells incubated with these salts did not disturb the cell cycle phases; instead, an increase in the number of apoptotic cells was observed. Regarding potential antiinvasion effects, both 1 and 2 prevented cell migration as well as cell invasion. Finally, when salts 1 and 2 were associated with vemurafenib, a marked decrease in cell viability was observed when compared to the compounds incubated alone. Briefly, the salts exhibited interesting results, especially 1, which decreased the expression of NRAS, increased apoptotic cells and, when combined with vemurafenib, resulted in a synergistic effect. Therefore, we intend to test compound 1 in pre-clinical studies.

Proteomic Identification of eEF1A1 as a Molecular Target of Curcumol for Suppressing Metastasis of MDA-MB-231 Cells

“…In addition, ACAT2 (Q9BWD1) was involved in diverse metabolic pathways, such as those of butanoate, glyoxylate, dicarboxylate, propanoate, tryptophan, pyruvate, and fatty acids. It has been reported that downregulation of NRAS was closely correlated with the antimetastatic effect of isothiouronium salts in melanoma cells, miR-515-5p in breast cancer cells and introduction of let-7i to mutant p53 cells . Additionally, a strong correlation was found among metastasis, ACAT2, and hydroxyl-coenzyme A dehydrogenase, alpha subunit (HADHA) downexpression and poorer prognosis on survival of clear cell renal cell carcinoma (ccRCC) …”