KLF4 and type 2 diabetes mellitus: We verified the seven shared genes which were reported to be related to the pathological mechanism of T2DM and OA in the validation cohorts and found that CEBPB, MAFF and GADD45B were lowly expressed in the OA group (p < 0.05) (Figure S1A), while EPHA3, UBAP1 and KLF4 were lowly expressed in the DM group (p < 0.05) (Figure S1B).