For example, tumor cell analysis of T-cell surface cell markers CD3, CD8, FOXP3, PD-1, PD-L1, and pancytokeratin by immunofluorescence, whole-exome sequencing, and RNA sequencing shows that active smoking decreases IFN-mediated signaling and cytotoxic T cell activity in immune-mediated tumor destruction [17]. This evidence concerns the gene PDCD1 and neoplasm.