Figure 4.

Mammary carcinoma cells upregulate alternative polarization of macrophages by eliciting activation of Hedgehog signaling Transcript levels of Arg1 (a (p = 0.0008), c (p = 0.01)) and Cd206 (b (p = 0.002), d (p = 0.002)) are significantly upregulated in presence of conditioned medium (CM) from 4T07 and 4T1 invasive mammary carcinoma cells. Treatment with GANT61 (10 μM) or KAAD-Cyclopamine (20 μM) significantly decreased the immunosuppressive polarization induced by the CM (Arg1 in 4T07 cells: p = 0.0034; Arg1 in 4T1 cells: p = 0.022; Cd206 in 4T07 cells: p = 0.0013; Cd206 in 4T1 cells: p = 0.006). The addition of Hh ligand squelching antibody, 5E1 (2.5 μg/ml), significantly decreases the effect of the 4T1 and 4T07 CM on its ability to induce a potent M2 phenotype marked by Arg1 (e, h), Cd206 (f, i), and Il-10 (g, j) (p < 0.0001 for all comparisons). *statistically significant difference.