Identifying CDKN3 gene expression as a prognostic biomarker in lung adenocarcinoma via meta-analysis

 Lung cancer is among the major causes of cancer deaths, and the survival rate of lung cancer patients is extremely low. Recent studies have demonstrated that the gene CDKN3 is related to neoplasia, but in the literature severe controversy exists over whether it is involved in cancer progression or, conversely, tumor inhibition. In this study, we investigated the expression of CDKN3 and its association with prognosis in lung adenocarcinoma (ADC) and squamous cell carcinoma (SCC) using datasets in Lung Cancer Explorer (LCE; http://qbrc.swmed.edu/lce/). We found that CDKN3 was up-regulated in ADC and SCC compared to normal tissues. We also found that CDKN3 was expressed at a higher level in SCC than in ADC, which was further validated through meta-analysis (coefficient = 2.09, 95% CI = 1.50–2.67, P < 0.0001). In addition, based on meta-analysis for the prognostic value of CDKN3, we found that higher CDKN3 expression was associated with poorer survival outcomes in ADC (HR = 1.65, 95% CI = 1.39–1.96, P < 0.0001), but not in SCC (HR = 1.10, 95% CI = 0.84–1.44, P = 0.494). Our findings indicate that CDKN3 may be a prognostic marker in ADC, though the detailed mechanism is yet to be revealed.