GNAI2 and lung adenocarcinoma: Three genes of the purple module, including CACNA1C, RAPGEF3, and GNAI2, are involved in the regulation of the insulin secretion pathway. Talip Zengin et al.105 introduced the RAPGEF3 for prognostic risk prediction according to overall survival time for lung adenocarcinoma patients. Xiao Wang and colleagues106 have done genome sequencing analysis for lung adenocarcinoma and introduced CACNA1C as a cancer-related gene.