COL4A1 and cancer: Col IV is generated from six kinds of collagen α chains (COL4A1-6) Based on previous studies, COL4A family members have been reported to be involved in the progress of focal segmental glomerulosclerosis (Gast et al., 2016), Alport syndrome (Ozdemir et al., 2020) and cancers (Miyake et al., 2017).