NOTCH4 and hepatocellular carcinoma: To directly test this theory, we knocked down Notch4 and VE‐cadherin expression with shVE‐cadherin and shNotch4, and observed the effects on the HCC VM formation following shAR. This blocking experiment revealed that shVE‐cadherin and shNotch4 significantly decreased the expression of VE‐cadherin and Notch4 increased by shAR in SK and HA22T cells.