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Small Molecule Inhibitors Targeting Gαi2 Protein Attenuate Migration of Cancer Cells
Silvia Caggia1, Subhasish Tapadar2, Bocheng Wu2
1Center for Cancer Research and Therapeutic Development, Clark Atlanta University, Atlanta, GA 30314, USA.
Abstract:
Heterotrimeric G-proteins are ubiquitously expressed in several cancers, and they transduce signals from activated G-protein coupled receptors. These proteins have numerous biological functions, and they are becoming interesting target molecules in cancer therapy. Previously, we have shown that heterotrimeric G-protein subunit alphai2 (Gαi2) has an essential role in the migration and invasion of prostate cancer cells. Using a structure-based approach, we have synthesized optimized small molecule inhibitors that are able to prevent specifically the activation of the Gαi2 subunit, keeping the protein in its inactive GDP-bound state. We observed that two of the compounds (13 and 14) at 10 μΜ significantly inhibited the migratory behavior of the PC3 and DU145 prostate cancer cell lines. Additionally, compound 14 at 10 μΜ blocked the activation of Gαi2 in oxytocin-stimulated prostate cancer PC3 cells, and inhibited the migratory capability of DU145 cells overexpressing the constitutively active form of Gαi2, under basal and EGF-stimulated conditions. We also observed that the knockdown or inhibition of Gαi2 negatively regulated migration of renal and ovarian cancer cell lines. Our results suggest that small molecule inhibitors of Gαi2 have potential as leads for discovering novel anti-metastatic agents for attenuating the capability of cancer cells to spread and invade to distant sites.
Insights
Small molecule inhibitors targeting the G-alpha-i2 (Gαi2) subunit effectively blocked prostate cancer cell migration and invasion. These findings highlight Gαi2 inhibitors as potential anti-metastatic agents for various cancers.
Area of Science:
- Oncology
- Molecular Biology
- Pharmacology
Background:
- Heterotrimeric G-proteins are crucial in cancer signaling pathways.
- The G-alpha-i2 (Gαi2) subunit plays a key role in prostate cancer cell migration and invasion.
- G-protein coupled receptors (GPCRs) signal transduction is implicated in cancer progression.
Purpose of the Study:
- To develop and evaluate small molecule inhibitors targeting the G-alpha-i2 (Gαi2) subunit.
- To assess the efficacy of Gαi2 inhibitors in blocking cancer cell migration and invasion.
- To explore the potential of Gαi2 as a therapeutic target for anti-metastatic agents.
Main Methods:
- Structure-based drug design was employed to synthesize small molecule inhibitors.
- In vitro assays were used to test the inhibitory effects of compounds 13 and 14 on prostate cancer cell lines (PC3, DU145).
- Gαi2 activation and cancer cell migration were assessed under various stimulation conditions, including oxytocin and EGF.
Main Results:
- Compounds 13 and 14 significantly inhibited the migration of PC3 and DU145 prostate cancer cells at 10 μM.
- Compound 14 blocked Gαi2 activation in oxytocin-stimulated PC3 cells and inhibited migration in DU145 cells overexpressing active Gαi2.
- Gαi2 knockdown or inhibition reduced migration in renal and ovarian cancer cell lines.
Conclusions:
- Small molecule inhibitors targeting Gαi2 are effective in reducing cancer cell migration and invasion.
- Gαi2 is a promising therapeutic target for developing novel anti-metastatic drugs.
- These inhibitors hold potential for attenuating cancer cell spread to distant sites.
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