Abstract
BACKGROUND: Thyroid carcinoma is the most common malignant endocrine tumour, and its prevalence has been on the rise in recent years. However, mechanisms underlying the metastasis of thyroid carcinoma and candidate biomarkers remain elusive. In this study, we screened genes involved in the virulence and metastasis of papillary thyroid carcinoma (PTC). METHODS: Oxford Nanopore Technology full-length transcriptome sequencing and bioinformatic analyses were performed to analyse differentially expressed genes (DEGs) in PTC. We collected 15 cancerous and paracancerous tissue pairs from patients with PTC for RNA sequencing. The significance thresholds for DEGs were |log2(fold change)| ≥ 1 and false discovery rate (FDR) < 0.01. Gene Ontology and Kyoto Encyclopaedia Gene and Genome pathway enrichment analyses of the 50 most significant DEGs were performed. Immunohistochemistry was used to evaluate LAMB3 expression in tissue microarrays (58 pairs of PTC samples) and its correlation with clinicopathological parameters. Differences in gene expression between cancerous and paracancerous tissues were analysed using the Wilcoxon test. The correlation between gene expression and clinical variables was assessed using Fisher's exact test. RESULTS: Transcriptomic analysis revealed the presence of 1,687 DEGs in PTC, and the expression of 804 and 883 genes was found to be upregulated and downregulated, respectively. LAMB3 expression was significantly elevated in cancerous tissues when compared to that in paracancerous tissues (p < 0.001). LAMB3 expression was significantly positively associated with PTC tumour tissue size (p = 0.001, r = 0.49) and T stage (p = 0.017, r = 0.339). CONCLUSIONS: Our findings suggest that LAMB3 expression significantly increases in PTC and it is associated with tumor size and T stage.