ADRB2 and lung adenocarcinoma: This is consistent with the results of the prognostic utility of key genes in lung adenocarcinoma, as the heatmap showed that CAV1, ADRB2, CBX7, and ITGAB8 which were favorable factors for lung adenocarcinoma were remarkably upregulated in gene-T3, and the remaining risk factors for lung adenocarcinoma were significantly upregulated in the gene-T2 subtype.