DKK1 and head and neck squamous cell carcinoma: Figure 7B provides more information on the various genetic alterations in DKK1. Using the UCSC Xena database, we verified the levels of CNV, somatic mutations, and DNA methylation of DKK1 in HNSCC. DKK1 mRNA expression in HNSCC was associated with CNVs and DNA methylation; however, it was not associated with somatic mutations, as illustrated in the heatmap (Figure 7C). According to cBioPortal data, samples with amplified DKK1 had higher levels of DKK1 mRNA (Figure 7D).