IGF2 and lupus nephritis: Available literature suggests that circHLA-C plays an important role in lupus nephritis through the sponge miR-150;23 circTTN promotes proliferation and differentiation of myogenic cells through IGF2/PI3K/AKT signaling pathway as miR-432 sponge (a);24 circRNF13 inhibits proliferation and metastasis of nasopharyngeal carcinoma through SUMO2;25 circUGGT2 (hsa_circ_0030632) is associated with colorectal and hepatocellular carcinoma.26,27