Fig. 3. In vivo treatment with palbociclib in MSTO-211H subcutaneous xenografted MPM model.

A xenografted subcutaneous tumour model was established by inoculation of MSTO-211H cells into the flanks of athymic nude mice (n = 7 per group). Tumours’ volume (a) was monitored by calliper measure every 4 days (at each time point, a SD bar is shown). b Differences in tumour volume for each day were represented using boxplots and compared using Kruskal–Wallis test, adjusted by FDR and were significantly different at day 16. At the end of the experiment, mice were sacrificed and (c, d) the tumours were removed, weighted and photographed. Asterisks indicated the absence of apparent macroscopic tumour at sacrifice, while residual cells were identified by H&E analysis. e Summary of the body weight values among first and last day of treatment from all mice in in vivo subcutaneous tumour xenograft growth experiment. Palbociclib did not exert any substantial change in the mice body weight. Differences were evaluated by Mann–Whitney test and adjusted for FDR. f Representative IHC images for (F.A) mouse macrophages that express F4/80 (brown staining) and (F.B) mouse NK cells that express NCR1 (brown staining) infiltrated in the subcutaneous MPM tumours xenografted in athymic nude mice after 26 days of treatment with vehicle, platinum plus pemetrexed or palbociclib. Inset photos contain the digital whole slide image showing the infiltrated area of tumour. Scale bar = 50 µm. Dot plots showing (g) the mean F4/80⁺ intensity per pixel (x-axis) or (h) the percentage of NCR1⁺ cells over total cells infiltrated in the subcutaneous MPM tumour xenografted in athymic nude mice after 26 days of treatment with vehicle, platinum plus pemetrexed or palbocilib (n = 5–7 per group). Data are expressed as single data values (dots) + the mean. ANOVA test was used to detect statistical differences between treatments (*p < 0.05).