TRIM46 deficiency‑induced DNA damage enhances the sensitivity of cisplatin in non‑small cell lung cancer by regulating the Akt signaling pathway.

Lung cancer is one of the most aggressive malignancies worldwide. Non‑small cell lung cancer (NSCLC), in particular, is characterized by a poor 5‑year survival rate, which is largely attributable to cisplatin (DDP) resistance. However, the molecular mechanisms underlying DDP resistance are still not fully understood. Tripartite motif 46 (TRIM46) is implicated in promoting the progression of lung adenocarcinoma and enhancing chemoresistance. Nevertheless, its specific role in DDP resistance remains elusive. The present study aimed to investigate the role of TRIM46 in DDP resistance. Immunohistochemistry and TUNEL staining were employed to detect the expression of TRIM46 and apoptotic cells in tumor tissues. Lentiviruses were used to construct TRIM46 overexpression and knockdown vectors in A549 and A549/DDP cells. Cell proliferation, apoptosis and DNA damage were measured by Cell Counting Kit‑8, flow cytometry and comet assay, respectively. Subcutaneous implantation model through injection of A549/DDP cells with TRIM46 knockdown was performed in BALB/c nude female mice, followed by DDP treatment. The results revealed that TRIM46 was highly expressed in DDP‑resistant NSCLC tumor tissues and positively associated with DDP resistance. TRIM46 overexpression attenuated the DDP‑induced apoptosis and DNA damage of A549 cells. Meanwhile, the knockdown of TRIM46 enhanced the DDP‑induced apoptosis and DNA damage in A549/DDP cells. Mechanistically, TRIM46 activated the Akt signaling, thus inhibiting the expression of caspase 3 and cleaved‑caspase 3 as well as increasing the expression level of DNA repair protein RAD51. Furthermore, TRIM46 deficiency inhibited tumor growth and increased DDP sensitivity in vivo. In conclusion, the results of the present study demonstrated that TRIM46 contributed to DDP resistance by regulating the Akt signaling pathway and DNA damage, thereby offering new strategies for lung cancer therapy.