Beta-Blockers as Potential Adjuvants in Melanoma Treatment

Melanoma, in advanced stages, is the most invasive type of skin cancer, with currently available treatments showing limited efficiency. The number of melanoma cancer cases is expected to increase in the coming years, emphasizing the need for more efficient therapeutic strategies. The present study aimed to evaluate the potential of β-blockers, commonly used to treat cardiac conditions, to be repurposed for the treatment of melanoma. The effects of non-selective β-blockers (carvedilol and propranolol), β1 selective blockers (atenolol and metoprolol) and antineoplastics drugs (cisplatin and 5-fluorouracil) on the A375 melanoma cell line were studied, individually and in combined exposures, by assessing cell viability over a 72 h period. The 72 h half-maximal inhibitory concentrations (IC₅₀s) determined for A375 cells allow the ranking of toxicity as: cisplatin (2.46 (1.87-3.38) μM) > 5-fluorouracil (4.77 (4.48-5.07) μM) > carvedilol (16.91 (15.47-18.99) μM) > propranolol (58.03 (57.08-59.11) μM) > atenolol and metoprolol (β1 selective blockers that exhibited no significant effect on the cell's viability). The effects of combined exposures were also studied. Metoprolol and carvedilol exhibited synergistic interactions with cisplatin at specific concentrations. Overall, the data highlight the concentration-dependent nature of mixture effects and support the potential application of β-blockers melanoma treatment.