COL1A1 and hyperinsulinism: Under hyperglycemic conditions, hyperinsulinemia slightly upregulated CDH1 (FCHG, ins = 1.23) and COL1A1 expression (FCHG, ins = 0.75) compared to the respective untreated hyperglycemic controls, whereas MMP9 levels (FCHG, ins = 0.56) were downregulated.