INTRODUCTION: Melanoma is a common type of skin cancer originating from melanocytes. Its standard treatments include surgery, chemotherapy, radiotherapy, and targeted therapy. However, due to limitations in drug treatments, new targets must be identified. One important enzyme in carcinogenesis, CA-IX, creates an acidic and hypoxic niche within tumor cells. Additionally, EZH2, a gene that encodes a histone-lysine N-methyltransferase, is involved in DNA methylation and plays a crucial role in cancer development by modulating epigenetic changes. In this study, our goal is to elucidate the effect of CA-IX inhibition on the EZH2 gene in melanoma.
METHODS: We evaluated the effects of CA-IX inhibition with AZA on EZH2 gene expression levels in the A375 human melanoma cell line. Cell culture, ELISA, and qPCR experiments were conducted. The cytotoxic activities of AZA were assessed using the WST-1 assay. CA-IX protein levels were measured using a Human Carbonic Anhydrase IX ELISA Kit. qPCR was performed using the QuantiNova LNA Probe PCR assay.
RESULTS: An IC50 value was observed at a concentration of 10.7 μM for AZA in the WST-1 assay. Decreased CA-IX protein levels were observed following AZA treatment (p<0.0001). Additionally, EZH2 mRNA levels were significantly reduced when CA-IX protein was inhibited by AZA (p<0.05).
DISCUSSION AND CONCLUSION: Inhibition of CA-IX and the consequent changes in the acidity of the tumor microenvironment may modulate EZH2 levels. CA-IX could be a promising target for the epigenetic treatment of melanoma.