RAC2 and chronic kidney disease: The lncRNA-miRNA-mRNA-pathway network constructed indicated that HCP5 might be regulatory genes associated with the progression of CKD via the genes of CCND2, COL3A1, COL4A1, and RAC2. The CCND2 gene encodes a protein G1/S-specific cyclin-D2 in humans, which belongs to the highly conserved cyclin family.