PGK1 and head and neck squamous cell carcinoma: In addition, the Speedman correlation coefficient analysis between copy number variation and gene expression was carried out, and it was found that the copy number variation of IL10 was down-regulated in HNSCC, while CDKN2A, EFNB2, TRIB3, PGK1, EPO were upregulated (Figure 11F), Therefore, abnormal gene expression may be the result of a combination of single nucleotide variation and copy number variation.