Lee S, et al. - Gene expression patterns in papillary thyroid microcarcinoma (PTMC) with lateral neck-node metastasis (N1b) vs PTMC-lacking nodal metastasis (N0) were determined. In three PTMCs without cervical lymph-node metastases (N0) and five PTMCs with lateral neck-node metastasis (N1b) at initial diagnosis, researchers performed oligonucleotide microarray analysis using an Illumina HumanHT-12 v4.0 Expression BeadChip. In samples from 20 N0 and 24 N1b PTMC patients who underwent thyroidectomy, immunohistochemistry (IHC) was done to confirm protein overexpression. In microarray analyses, 52 probes corresponding to 45 genes were identified. In N1b PTMC compared with N0, they observed significant upregulation of 40 genes and downregulation of five genes. N1b PTMCs displayed significant upregulation of four genes linked to epithelial-to-mesenchymal transition and stem cell markers, including ALDH1A3, TM4SF1, PROM1, and CAV1. Confirmation of this expression was made via real-time qPCR and Confirmation of higher expression of ALDH1A3, TM4SF1, PROM1, and CAV1 in N1b than in N0 PTMCs was done using western blot analysis. As per IHC, ALDH1A3 and CAV1 are overexpressed in N1b compared with N0 PTMCs.