CD4 and head and neck squamous cell carcinoma: As was shown in Fig. 3A, after adjusting for the influence of tumor purity, LAYN expression was positively associated with the infiltrating levels of B cells (P < 0.05), CD4 + T cells (P < 0.001), macrophages (P < 0.001), and dendritic cells (P < 0.001) in HNSCC tumor tissues, while the correlation was not statistically significant with CD8 + T (P = 0.79) and neutrophils (P = 0.12).