Related Experiment Video
Updated: Aug 23, 2025
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Comparing the Affinity of GTPase-binding Proteins using Competition Assays
Published on: October 8, 2015
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RAB4A GTPase regulates epithelial-to-mesenchymal transition by modulating RAC1 activation.
Subbulakshmi Karthikeyan1, Patrick J Casey1,2, Mei Wang3,4
1Program in Cancer Stem Cell Biology, Duke-NUS Medical School, 8 College Road, Singapore, 169857, Singapore.
Breast Cancer Research : BCR
|October 29, 2022
Summary
Researchers found that RAB4A protein is essential for epithelial-to-mesenchymal transition (EMT), a process driving cancer growth and spread. Targeting RAB4A may offer new therapies for advanced cancers.
Area of Science:
- Oncology
- Cell Biology
- Molecular Biology
Background:
- Epithelial-to-mesenchymal transition (EMT) is crucial for cancer progression, recurrence, and drug resistance.
- Identifying novel EMT regulators is key to developing effective cancer therapies.
Purpose of the Study:
- To investigate the role of RAB4A in regulating EMT and cancer progression.
- To elucidate the downstream signaling pathways involved in RAB4A-mediated EMT.
Main Methods:
- Utilized in vitro and in vivo models to study RAB4A function.
- Assessed cancer cell stemness, self-renewal, and tumor formation.
- Investigated the involvement of RAC1 GTPase activation.
Main Results:
- RAB4A is essential for EMT, stemness, and invasive properties in cancer cells.
- Suppression of RAB4A inhibited self-renewal and tumor formation.
- RAB4A regulates EMT via control of RAC1 GTPase activation, which can rescue EMT phenotypes when introduced.
Conclusions:
- A RAB4A-RAC1 signaling axis is identified as a key regulator of EMT and cancer progression.
- This pathway represents a potential therapeutic target for controlling cancer spread and improving treatment outcomes.
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