Gap26 inhibited angiogenesis through the β-catenin-VE-cadherin-VEGFR2-Erk signaling pathway

PURPOSE

To investigate the effect of connexin 43 (Cx43) on corneal neovascularization and its regulation of VEGFR2 on vascular endothelial cells.

METHODS

In vivo, we used mouse corneal suture model to induce corneal neovascularization and discovered the function of gap26 in corneal neovascularization. In vitro, the effect of gap26 on HUVEC was observed by cell proliferation, tube formation and scratch experiments. WB and PCR detected the changes in angiogenic protein and mRNA expression. Knockdown of key mRNA in neovascularization using siRNA confirmed that Cx43 regulates neovascularization through the β-catenin-VE-cadherin-VEGFR2-Erk signaling pathway.

RESULTS

In vivo, gap26 can reduce mouse corneal neovascularization. In vitro, we show that Cx43 expression is increased in the presence of VEGFA stimulation, and when we use gap26 to inhibit Cx43 can reduce vascular endothelial cell proliferation, tube formation and migration. We found that the expression of pVEGFR2 and pErk increased in response to VEGFA, while they decreased after using gap26. And the expression of β-catenin and VE-cadherin decreased in response to VEGFA, while they increased after using gap26. Furthermore, we found that Cx43 regulates angiogenesis through the β-catenin-VE-cadherin-VEGFR2-Erk pathway.

CONCLUSIONS

Gap26 can downregulate VEGFR2 phosphorylation by stabilizing the expression of β-catenin and VE-cadherin on the cell membrane, thereby inhibiting VEGFA-induced HUVECs proliferation, migration and tube formation and inhibiting corneal neovascularization.

Clinical significance of TRIM29 expression in patients with gastric cancer

Aim

The present study aimed to evaluate the expression profile, prognostic value, and possible correlation of TRIM29 with β-catenin, Cyclin D, and Bcl2 in Iranian patients with GC.

Background

Tripartite Motif Containing 29 (TRIM29) has been reported to function as an oncogene or a tumor suppressor depending on the tumor type. This contextual function has created a controversial situation that needs to be fully delineated in various cancers. Although few studies have reported an elevated TRIM29 expression in gastric cancer (GC), its clinicopathological and prognostic values as well as possible molecular mechanisms are yet to be re-evaluated in different populations.

Methods

Real-time quantitative PCR was used to detect TRIM29, β-catenin, Cyclin D, and Bcl-2 expression in 40 GC and their adjacent normal tissues. Patients were further stratified into high and low expression subgroups based on their TRIM29 expression levels. The association of TRIM29 expression level with β-catenin, Cyclin D, BCL2, some clinicopathological features, and patients' overall survival (OS) was assessed using appropriate statistical analyses.

Results

The results showed a significantly higher TRIM29 expression level in GC tissues compared with their corresponding normal tissues (fold change=2.94, p=0.003). Patients with high TRIM29 expression levels exhibited poorer OS (HR=1.25, 95% CI: 1.06-1.47, p=0.007). High expression of TRIM29 was also associated with increased levels of β-catenin, Cyclin D, and Bcl-2 genes expression.

Conclusion

Overexpression of TRIM29 is associated with poor prognosis in patients with GC and is probably mediated through β-catenin/Cyclin D/Bcl2 pathway and can be considered as a potential independent prognostic marker.