Through bioinformatics analysis, our results demonstrate that the activation of the PTPN family is associated with significant changes in the proportions of TNFRSF9+ regulatory T cells (Tregs), effector memory CD8+ T cells re-expressing CD45RA (TEMRA), and M2 tumor-associated macrophages (TAMs), which also exhibit distinct differentiation trends. The gene discussed is CD8A; the disease is neoplasm.