CD274 and neoplasm: Attenuated pathogenic facultative anaerobic S. typhimurium VNP20009 decorated by heptamethine cyanine dyes NHS‐N782 and extra terminal domain (BET) protein inhibitor, JQ‐1 derivatives, invades into tumor cells, targets mitochondria in tumor cells, and downregulates PD‐L1 expression in TME to produce an effective and durable T cell immune response.366