Hiding the road signs that lead to tumor immunity

Tumors exploit many strategies to evade T cell–mediated destruction. For example, tumors can prevent T cell infiltration by modifying gene expression in the endothelial cells and pericytes that form their vasculature. New work showing that the T cell–attracting chemokine CCL2 can be posttranslationally modified in the tumor microenvironment adds another mechanism to the already formidable arsenal of immunoevasion tactics used by solid tumors.