Anti-VCAN monoclonal antibody, clone FQS23388

Background: Approximately half of the documented increases in differentiated thyroid carcinoma is due to identification of papillary thyroid microcarcinomas (PTMCs). Knowing whether PTMC is aggressive is required for proper treatment, but until now, there has been no method for assessing these traits and understanding the underlying mechanisms for aggressiveness. Methods: We performed whole-exome sequencing of 16 PTMCs and matched normal thyroid tissues and GO/KEGG analysis to study genetic alterations and biological consequences associated with aggressive PTMCs, and then sequenced these genes using a next-generation gene-panel approach in an additional 70 PTMC samples including aggressive (n = 50) and non-aggressive (n = 20) groups. Results: We identified 254 somatic mutations of 234 genes, for which 178 mutations in 168 genes were found in the aggressive group, and 76 mutations in 74 genes were found in the non-aggressive group. Several recurrent mutations in BRAF, VCAN, ALDH1L1, and MUC5B were identified, and many novel but infrequent mutations in other genes were also found. The aggressive cohort had more mutational burdens than the non-aggressive group (P = 0.004). Non-synonymous mutations of 13 genes (MUC5B, TNN, SSPO, PPFIA1, PCDHGA2, ITGA8, ITGA4, DCHS1, CRNN, ROCK1, RELN, LAMC2, and AEBP1) were involved in cell adhesion, and these were only present in the aggressive group. Targeted sequencing of these genes revealed significant enrichment in the aggressive group (P = 0.000004). Conclusion: PTC may have evolved from PTMC due to sharing similar gene mutations, and the accumulation of such mutations promoted the aggressiveness of PTMC. Gene mutants associated with cell adhesion may be used to predict PTMC aggressiveness and allow more selective treatment.

Loss of Tbx4 results in absence of chorio-allantoic fusion and failure of formation of the primary vascular plexus of the allantois leading to embryonic death at E10.5. We reviewed the literature for genes implicated in chorio-allantoic fusion, cavitation and vascular plexus formation, processes affected in Tbx4 mutant allantoises. Using this candidate gene approach, we identified a number of genes downstream of Tbx4 in the allantois including extracellular matrix molecules Vcan, Has2, and Itga5, transcription factors Snai1 and Twist, and signaling molecules Bmp2, Bmp7, Notch2, Jag1 and Wnt2. In addition, we show that the canonical Wnt signaling pathway contributes to the vessel-forming potential of the allantois. Ex vivo, the Tbx4 mutant phenotype can be rescued using agonists of the Wnt signaling pathway and, in wildtype allantoises, an inhibitor of the canonical Wnt signaling pathway disrupts vascular plexus formation. In vivo, Tbx4 and Wnt2 double heterozygous placentas show decreased vasculature suggesting interactions between Tbx4 and the canonical Wnt signaling pathway in the process of allantois-derived blood vessel formation.