LRRC15 and cancer: Elevated LRRC15 levels correlates with a poor response to anti-PD-L1 cancer immunotherapy in six immune-excluded cancer types (characterized by a dense stromal structure surrounding the tumor and the presence of most tumor-infiltrating cells in the stromal area, fewer in the tumor parenchyma), pancreatic cancer, bladder cancer, renal cell carcinoma, head and neck cancer, and non-small cell lung cancer (Figure 1) [63].