According to Fig. 5A, PD-L1 are most expressed in tumor stroma rather than tumor cell membranes, so a possible explanation for our results is that non-LD groups have much more expression of PD-L1 in tumor exosomes and distribute in tumor stroma, which could antagonize immunotherapy by binding to the antibody itself and induce immune resistance. The gene discussed is CD274; the disease is neoplasm.