As a role for secreted Hsp70 in MΦ M2 polarization has not been described previously, the finding that cancer-secreted Hsp70 controls MΦ polarization through TLR2 and MerTK receptors establishes a new immunosuppressive molecular communication mechanism between cancer cells and MΦ mediated by Hsp70. The gene discussed is TLR2; the disease is cancer.