Figure 6.

TMZ modifies glioma microenvironment favoring an NK cell antitumor activity. (A and B) Relative expression of the most immunosuppressive molecules normally expressed in glioma cells: galectin-1, −3, −9 (3.85 ± 0.03-, 2.94 ± 0.02- and 2.22 ± 0.03-fold, respectively vs. controls) and H2-q1 (2.81 ± 0.08-fold vs. controls). (C) Cytokine and chemokine protein array blots with pixel density quantification of lysates from gliomas of control and TMZ-treated mice (n = 5 / group of treatment). Blots are representative of experiments performed on a pool of gliomas from controls or TMZ-treated mice. Cytokines and chemokines which expression changed in both experiments were considered: IFNγ, CCL3, TNF-α, IL-7 and IL-27 were 1.9 ± 0.6-, 1.6 ± 0.4-, 1.7 ± 0.2-, 1.8 ± 0.4-, 1.6 ± 0.2-fold higher, CXCL10 and CCL5 were 0.6 ± 0.7- and 0.7 ± 0.4-fold lower in TMZ-treated compared to controls; *p ≤ 0.01. (D) TGF-β1 and -β2 levels in medium of GL261 cells treated in vitro with DMSO or TMZ: from 23.2 ± 2.5 pg/mL and 478.4 ± 19.3 pg/mL in vehicle to 13.2 ± 2.2 pg/mL and 283.8 ± 25.9 pg/mL in TMZ-treated cells. (E) Relative expression of Nkg2d ligands in GL261 cells treated in vitro with 50 and 150 μM TMZ (striped and black bars, respectively) and DMSO used as vehicle (white bars) at different time points. *p < 0.01; **p < 0.001; ***p < 0.0001.