PDCD1 and breast cancer: Despite the absence of available data on obese BC patients, in obese female mice fed with an obesogenic high-fat diet, injected with BC E0771 cells and treated with anti-PD-1 therapy, it has been demonstrated a significant decrease in tumor volume, a reduced cell proliferation and a concomitant elevation of CD8+ T cells, CD4+ Th1 cells and dendritic cells [83].