Fig. 3

Proliferation index of mucosal melanoma cells from PDX models containing CDK4 aberrations after CDK4/6 inhibitors treatments. On day 14 of treatments, the tumor nodules were excised and examined by H&E staining and immunohistochemical staining (for Ki-67). The sections were evaluated under microscope, and typical staining was photographed (a). The Ki-67 + cells under 5 random fields were counted. Bar = 20 μm. The results of Ki-67 + cells (b–f) were presented as mean ± SD of three sections. ns no significances; *P < 0.05; **P < 0.01; ***P < 0.001