NOTCH4 and hepatocellular carcinoma: Compared with non-HCC tissues from three studies14,19,21, Notch 4 was associated with an increasing tendency in HCC tissues (OR = 1.33, 95%CI: 0.74 to 2.38; P = 0.351, I2 = 9.7%; Fig. 2D), with moderate quality evidence according to the GRADE assessment (Table 2).