MMP1 and hepatocellular carcinoma: Our results indicated that when MBD3 is highly expressed in HCC, the tumour suppressor TFPI2 would be inhibited, thus the activity of MMPs, such as MMP1, MMP10 and the PI3K/AKT signaling pathway will be reactivated, which will promote the proliferation and metastasis of tumour cells and lead to the deterioration of HCC (Figs. 5g, h and S3).