CDK4 and lung cancer: To further verify the role of NDUFA4 in the growth and metastasis of lung cancer cells, we detected the expression of cell-growth-related molecules including CDK2, CDK3, CDK4, and CDK6, as well as metastasis-related molecules including CXCR4, E-Cadherin, MMP2, MMP3, and MMP9, respectively.