CD4 and cancer: Thus, by delivering a range ofnucleic acidse.g., pDNA,PNA, mRNA, siRNA, miRNA, and CpGpolyplexes formed from functionalpolymers have the potential to restore immune cell recognition andactivation against cancer cells that are suppressed within the tumormicroenvironment. One emerging strategyfor achieving this is to deliver nucleic acids encoding TAAs to antigen-presentingcells (APCs), which can present TAAs via major histocompatibilitycomplex (MHC) class I and II molecules, stimulating CD8+ and CD4+ T cell responses against cancer cells.