Fig. 3

Morphometric analysis of tumor xenografts. Sections from PC9T790M xenografts treated with osi (a), osi + pem → osi (b) or osi + cis → osi (c) stained by Masson’s Trichrome to distinguish the fibrotic tissue (greenish) from neoplastic cells (purple). Tumors are encircled by black lines to exclude the skin, adnexa and uninvolved soft tissues. Scale bars = 1 mm. Higher magnifications of the same samples are shown on corresponding lower panels in which the increased amount of collagen deposition after treatment with osi + pem → osi or osi + cis → osi is apparent. Scale bars = 100 μm. Bar graphs showing the quantitative evaluation of tissue composition (neoplastic tissue, fibrosis and necrosis) in tumor xenografts following pharmacological treatment with osi alone or in association with pem (d) or cis (e). *p < 0.05, **p < 0.01 vs osi group; Student’s t-test