AI Article Synopsis
- Semaphorins are proteins that help direct axon growth, with Plexin B1 acting as a newly identified tumor suppressor in melanoma by blocking the oncogenic receptor c-Met.
- Research revealed that Plexin B1 inhibits integrin-dependent processes, specifically reducing pp125(FAK) activation and integrin-dependent migration in melanoma cells.
- Plexin B1 also lowers Rho protein activity in these cells, including suppression of Rho activation triggered by hepatocyte growth factor (HGF).
Article Abstract
Semaphorins are secreted and membrane bound proteins that regulate axon guidance through receptors Plexins and neuropilins. Plexin B1, the Semaphorin 4D receptor, is a recently described tumor suppressor protein for melanoma. We recently showed that Plexin B1 abrogates activation of the oncogenic receptor, c-Met, by its ligand, hepatocyte growth factor (HGF), in melanoma. We have now investigated the effect of Plexin B1 on integrin-dependent pp125(FAK) activation, and the small GTP-binding protein Rho, in melanoma. Integrin receptors and Rho play critical roles in melanoma progression, through regulation of migration, proliferation and apoptosis. We engineered two human melanoma cell lines expressing Plexin B1 and analyzed integrin-dependent migration, integrin-dependent pp125(FAK) activation, and Rho activity. Results show that Plexin B1 abrogates integrin-dependent migration and activation of pp125(FAK). We also show that Rho activity is significantly reduced in cells expressing Plexin B1, and that Plexin B1 suppresses HGF-dependent Rho activation.
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| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3692372 | PMC |
| http://dx.doi.org/10.1111/j.1755-148X.2010.00797.x | DOI Listing |
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Plexin B1 inhibits integrin-dependent pp125FAK and Rho activity in melanoma.
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Article Synopsis
- Semaphorins are proteins that help direct axon growth, with Plexin B1 acting as a newly identified tumor suppressor in melanoma by blocking the oncogenic receptor c-Met.
- Research revealed that Plexin B1 inhibits integrin-dependent processes, specifically reducing pp125(FAK) activation and integrin-dependent migration in melanoma cells.
- Plexin B1 also lowers Rho protein activity in these cells, including suppression of Rho activation triggered by hepatocyte growth factor (HGF).
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