Targeting Endothelial Connexin37 Reduces Angiogenesis and Decreases Tumor Growth.

Area of Science:

• Vascular Biology
• Cancer Biology
• Cellular Physiology

Background:

• Connexins (Cx) form intercellular channels crucial for endothelial cell (EC) function and vessel regulation.
• Previous work implicated Cx37 and Cx40 in angiogenesis and tumor growth, with Cx40 loss decreasing tumor progression.

Purpose of the Study:

• To investigate the role of connexin37 (Cx37) in endothelial cell proliferation, vascularization, and tumor growth.
• To explore the collaborative function of Cx37 and Cx40 in tumor development.

Main Methods:

• In vitro proliferation assays of primary human EC.
• In vivo studies using Cx37 knockout mice and matrigel plugs with Cx37-targeting peptides.
• Tumor growth assessment in TC-1 and B16 models.
• Evaluation of vessel perfusion, mural cell coverage, and tumor hypoxia.

Main Results:

• Loss of Cx37 significantly reduced in vitro EC proliferation and in vivo vascularization.
• Cx37 deficiency impaired tumor angiogenesis and suppressed TC-1 and B16 tumor growth, extending mouse survival.
• Cx37 and Cx40 exhibit collaborative roles in promoting tumor growth, with combined targeting showing enhanced efficacy.

Conclusions:

• Cx37 is a key regulator of EC proliferation and is essential for tumor angiogenesis and growth.
• Targeting Cx37, alone or in combination with Cx40, represents a potential therapeutic strategy for anti-tumoral treatments.