Methylation of the promoter region of the RASSF1A gene silences the gene and inhibits the macrophage stimulating 1/2 (Mst1/2) protein, thereby activating the core protein Yes-associated protein/Tafazzin (YAP/TAZ) of the Hippo pathway; this inhibits the apoptosis of cancer cells and promotes the proliferation of cancer cells [34, 35], and the Hippo pathway plays an important role in the formation of HB [36] (Fig. 1). The gene discussed is MST1; the disease is cancer.