ALTERATIONS IN THE APOPTOSIS-ASSOCIATED GENE EXPRESSIONS IN LUNG CANCER CELLS IN THE PRESENCE OF IXAZOMIB AND GIVINOSTAT

Objective: Proteasome inhibitors and histone deacetylase (HDAC) inhibitors represent promising therapeutic agents in lung cancer, particularly by enhancing cancer cell sensitivity to treatment. Among these, the combination of ixazomib, a proteasome inhibitor, and givinostat, an HDAC inhibitor, has demonstrated synergistic cytotoxicity in non-small cell lung cancer (NSCLC) cell lines. This strategy holds potential for overcoming therapeutic resistance. Furthermore, macrophage co-culture systems have been shown to modulate gene expression patterns in lung cancer cells. In this context, the present study aimed to investigate the effects of ixazomib and givinostat, individually and in combination, along with differentiated M1 macrophages, on the expression of apoptosis-related genes in NSCLC cells. Material and Method: The IC50 values of ixazomib and givinostat in A549 lung cancer cells were determined using the MTT assay after 24 hours of treatment with a range of concentrations (400, 100, 10, and 1 µM). Based on the determined IC50 values, A549 cells were treated with ixazomib alone or in combination with givinostat for 24 hours. In parallel, A549 cells treated with the ixazomib–givinostat combination were co-cultured with THP-1 monocyte–derived M1 macrophages. Total RNA was then isolated, and RT-PCR analysis was performed to evaluate alterations in apoptosis-related gene expression. Result and Discussion: Based on the results of the anti-proliferative effect analysis, the IC50 values for ixazomib and givinostat were determined to be 2.42 µM and 7.32 µM, respectively. According to the RT-PCR results, variations of up to 48.99-fold were observed in the NFKB2, NFKBIA, NFKBIB, RELB, IL-6, IL-8, TP53, PIK3CA, and BCR genes. Significant alterations were particularly observed in genes involved in apoptosis-related pathways, especially in the presence of M1 macrophages. Additional investigation is warranted to thoroughly explore the heightened inflammatory response observed in lung cancer cells in the presence of these drugs.