Correlation Between β-Catenin Expression and Staging in Nasopharyngeal Carcinoma Patients

EBV-IgA antibody responses in endemic and nonendemic populations with nasopharyngeal carcinoma: tumour marker prognostication study and a cross-sectional study

Nasopharyngeal carcinoma (NPC) is the most prevalent head and neck cancer in Indonesia, with 100% Epstein-Barr virus (EBV) infection in tumor cells. NPC is rare in the Netherlands. The involvement of EBV in NPC pathogenesis is reflected by early onset aberrant IgA antibody responses to various EBV proteins. Screening for elevated EBV-IgA levels is proposed for NPC risk assessment in endemic countries but is poorly studied in nonendemic regions. This study analyzed the overall diversity (immunoblot) as well as the prevalence and normalized levels of IgA responses to immunodominant peptide epitopes of EBV proteins VCA P18, EBNA 1, and Zebra (Zta) (N-terminus, P 125, P 130, full-length recombinant Zebra) in Indonesian (n=50) and Dutch (n=50) patients with NPC. The results confirmed that elevated levels of IgA-VCA P18 and IgA-EBNA 1 were found in both NPC populations, but that IgA-Zta was more variable. IgA-Zta responses were more pronounced in Indonesian NPC cases, reflecting more frequent EBV reactivation overall. IgA-VCA P18 and IgA-EBNA are independent tumor markers and are both necessary for NPC risk assessment. Overall, these results confirmed the diagnostic benefit of combined IgA-VCA P18/-EBNA 1 testing for NPC risk assessment in endemic and nonendemic populations.

N-Cadherin Expression with Metastasis of Neck Lymph Nodes in Patients with Nasopharyngeal Carcinoma

Background

Lymph node (LN) metastases were one characteristic of negative progress of NPC patient despite its advanced therapeutic approaches. One mechanism for the occurrence of epithelial to mesenchymal transition (EMT)-mediated metastases is by increasing N-cadherin expression. The purpose of this research is to determine investigating N-cadherin expression against metastatic LN in NPC cases.

Methods

Samples were taken by unproportionate stratified random sampling. N-cadherin expression was examined using immunohistochemistry methods. N-cadherin expression was assessed visually by binocular light microscopy. We analyzed these data using Mann-Whitney U-test to examine N-cadherin expression and lymph node metastases.

Results

A strong expression was found in N3 group by 63.6%; 27.3% in the N2 group and 9.1% in the N1 group. In patients with NPC N0 or without lymph node metastases, N-cadherin expression is 0%. The expression of N-cadherin is indeed an indicator of the occurrence of lymph node metastases in NPC with a statistically significant analysis of p = 0.026 (p < 0.05).

Conclusion

There were correlations between N-cadherin expression and lymph node metastasis on NPC patients.

Bacteroides fragilis Toxin Induces Intestinal Epithelial Cell Secretion of Interleukin-8 by the E-Cadherin/β-Catenin/NF-κB Dependent Pathway

Enterotoxigenic Bacteroides fragilis (ETBF) has emerged as a gut microbiome pathogen that can promote colitis associated cancer in humans. ETBF secretes the metalloprotease, B. fragilis toxin (BFT), which can induce ectodomain cleavage of E-cadherin and IL-8 secretion through the β-catenin, NF-κB, and MAPK pathways in intestinal epithelial cells. However, it is still unclear whether E-cadherin cleavage is required for BFT induced IL-8 secretion and the relative contribution of these signaling pathways to IL-8 secretion. Using siRNA knockdown and CRISPR knockout studies, we found that E-cadherin cleavage is required for BFT mediated IL-8 secretion. In addition, genetic ablation of β-catenin indicates that β-catenin is required for the BFT induced increase in transcriptional activity of NF-κB, p65 nuclear localization and early IL-8 secretion. These results suggest that BFT induced β-catenin signaling is upstream of NF-κB activation. However, despite β-catenin gene disruption, BFT still activated the MAPK pathway, suggesting that the BFT induced activation of the MAPK signaling pathway is independent from the E-cadherin/β-catenin/NF-κB pathway. These findings show that E-cadherin and β-catenin play a critical role in acute inflammation following ETBF infection through the inflammatory response to BFT in intestinal epithelial cells.