Abstract
This study aims to validate the biological markers of lung adenocarcinoma (LUAD) to increase early diagnosis and improve patient survival. Initially, the data of KPNA2 expression in LUAD was extracted from databases such as CCLE, TCGA, GTEx, and GEO, among others. The LUAD cells were transfected with lentivirus carrying KPNA2 cDNA or shRNA and screened with puromycin to construct the KPNA2 overexpression or knockdown stable cell lines. Further, the effect of KPNA2 on the LUAD cells in vitro was determined by the EdU assay for proliferation and flow cytometric (FCM) analysis to assess apoptosis and ROS levels. An immunofluorescence assay was used to detect the expression of MYC and its distribution. The interaction between KPNA2 and MYC was examined using co-immunoprecipitation (Co-IP) assays. Finally, a nude mouse tumorigenicity assay was applied to detect the influence of KPAN2 on tumor growth in vivo. According to database analysis, KPNA2 was expressed higher in LUAD tissues than adjacent normal tissues, indicating its positive correlation with the degree of tumor malignancy. In vitro, the cell experiments proved that KPNA2 overexpression promoted cell proliferation and inhibited apoptosis and ROS production, with an increase in glucose uptake, ATP, and lactate production. Moreover, KPNA2 up-regulated the expression of MYC and its intranuclear accumulation. As anticipated, the KPNA2 knockdown yielded the opposite results. The tumorigenesis experiments in nude mice in vivo showed that KPNA2 promoted tumor growth, inhibiting apoptosis of LUAD cells by the TUNEL assay. KPNA2 triggers glycolysis metabolism by inducing MYC into the nucleus, promoting LUAD development.