However, conflicting results have been reported in relation to the degree of claudin-1 expression and the prognosis, suggesting that the expression level of claudin-1 alone is not sufficient to analyze the relationship between claudin-1 and cancer progression.
This study demonstrated that DOCK1 mediates growth and motility through down-regulated claudin-1 expression via the RRP1BDNMTclaudin-1 pathway and that claudin-1 serves as an important effector in DOCK1-mediated cancer progression and metastasis in claudin-low breast cancer cells.
KEGG analysis of the cDNA microarray data revealed increased levels in the cell adhesion molecule (CAM) pathway, including CLDN10 and CLDN1, indicating that CAMs may play a role in LIPC-mediated tumor progression.
Claudins (CLDNs), the major integral membrane proteins at tight junction, play critical roles in apical cell-to-cell adhesion, maintenance of epithelial polarity, and formation of impermeable barriers between epithelial cells.We investigated in this study the expression of CLDNs- Claudin1 (CLDN1) and Claudin7 (CLDN7), and their relation to tumor progression in nasopharyngeal cancer (NPC).
Altered expression of claudin-1, claudin-7, and tricellulin in early tonsillar squamous cell carcinoma (SCC) independent of human papilloma virus (HPV) infection may lead to tumor progression.
Focusing on a specific subset of genes, we found that the ability of stromal ATF3 to promote cancer progression is mediated by transcriptional repression of CLDN1 and induction of CXCL12 and RGS4.
The data suggest that transcriptional events mediated by LPA in the tumor microenvironment influence tumor progression through modulation of cell adhesion molecules like claudin-1 and, for the first time, report an LPA-mediated expression signature in ovarian cancer that predicts a worse prognosis.
These findings support a potential role of the TJ protein CLDN1 in restricting nutrient and growth factor supplies in breast cancer cells, and they indicate that the loss of the cell membrane localization of the TJ protein CLDN1 in carcinomas may be a crucial step during tumor progression.