CD4 and neoplasm: Tissue microarrays containing both tumor center (TC) and invasive margin (IM) regions were constructed and multiplex immunofluorescence staining [HIF-1α/CD4/CD8/cytokeratin (CK)/4',6-diamidino-2-phenylindole (DAPI)] were performed to quantitatively analyze the densities of HIF-1α-expressing tumor cells (HIF-1α+CK+), HIF-1α+CD4+ T cells and HIF-1α+CD8+ T cells.