This research combinedly investigated four transcriptomics datasets both KC (GSE15641, GSE38424) and T2D (GSE29226, GSE25724) and suggested six shared significant genomic biomarkers (JUN, CD74, TFRC, CREB1, MCL1, SCARB1) by Limma approach, pathways, as well as regulators for prognosis, diagnosis and therapies of KC patients with T2D. The gene discussed is JUN; the disease is type 2 diabetes mellitus.