IGF1 and keloid: In the training dataset, the expression levels of CCNB1, EGFR, E2F8, BTG1, as well as TP63 were remarkedly lower in the keloid samples than in the control samples (P < 0.05); however, the expression of IGF1 was evidently enhanced in the keloid samples elative to the control samples (P < 0.05, Fig. 6C).