CD8A and small cell lung carcinoma: Furthermore, we injected SCLC MHC-I KO or SCLC WT orthotopically into immunocompetent mice and observed that MHC-I KO cells generated a higher tumor load in the lung than SCLC WT cells and were characterized by a markedly reduced CD8 T cell infiltration, indicating that loss of MHC-I evades T cell immunosurveillance (Supplementary Fig. 1c–k).