CDK4 and non-small cell lung carcinoma: Research involving cisplatin resistance in NSCLC has recently revealed that hsa_circ_0014235 in exosomes derived from the serum is markedly upregulated in NSCLC and facilitates cisplatin chemoresistance, while modulating the miR-520a-5p/CDK4 pathway, thus increasing NSCLC development 81.