STAT3 and cancer: Likewise, B7‐H3 overexpression‐induced spheroid formation was inhibited by cryptotanshinone (Figure 4F, Figure S3C), while the attenuated cancer cell stemness phenotypes observed upon silencing B7‐H3 were rescued by the transfection of STAT3C to promote STAT3 activation (Figure 4G, Figure S3D,E).