Immunohistochemical analysis of the treated tumors showed how Gemcitabine induces a robust senescent response in the tumor as observed from the positive senescence-associated beta-galactosidase (SABG) staining, the loss of proliferation marker Ki67, and the expression of cell cycle inhibitor p21 (Fig. 4d, e), all of them markers of cell senescence41. This evidence concerns the gene GLB1 and neoplasm.