Flow cytometry analysis of CD4 CD25 T cells as a percentage of total CD4 cells in PC patients suggests that increased Treg levels may contribute to immunosuppression and tumor progression.[39] Additionally, therapeutic strategies targeting CD25 in Treg cells[40–42] have shown promise in the treatment of PC, highlighting the potential of anti-CD25 immunotherapy in this context. Here, CD4 is linked to pachyonychia congenita.