RSPO4 and thyroid cancer: Since both RSPO4 and BRAF gene was highly expressed in our metastatic cohort (Figure 5A), we used Integrative Genome Viewer (IGV—https://software.broadinstitute.org/software/igv/, accessed on 1 January, 2022) to screened for common mutations described in thyroid cancer to identify those impacted on our target genes identified to discriminate between non-metastatic and metastatic PTC cases.