CTLA4 and cancer: Our findings seem to be in contrast with studies supporting the idea that high levels of CSF1 and tumor-associated macrophages (TAMs) are associated with a poor cancer prognosis [52] and that inhibition of CSF-1/CSF-1R signaling can improve the efficacy of checkpoint blockade in animal tumor models by enhancing anti-CTLA-4 and anti-PD-1-induced tumor immunity [53].