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Protocol to identify covalent inhibitors targeting RhoA Cys16
Tin-Yan Koo1, Chloe See-Hang Ho1, Hillary Yui-Yan Yip1
1School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam Road, Hong Kong, China.
Abstract:
Ras homolog family member A (RhoA) is a therapeutic hotspot in many cancers but remains undruggable. Here, we present a protocol for identifying covalent inhibitors targeting RhoA Cys16. We describe steps for the identification of lead compounds by activity-based protein profiling (ABPP) screening and the validation of engagement by mass spectrometry and chemical biology experiments. We then detail procedures for investigating the effects of the compounds on RhoA signaling in cancer cells and mouse colorectal cancer (CRC) models. For complete details on the use and execution of this protocol, please refer to Koo et al.1.
Insights
Researchers developed a new protocol to find covalent inhibitors for Ras homolog family member A (RhoA), a key cancer target. This method uses activity-based protein profiling to identify potential drugs for cancer therapy.
Area of Science:
- Biochemistry
- Chemical Biology
- Oncology
Background:
- Ras homolog family member A (RhoA) is a crucial signaling protein implicated in various cancers.
- Despite its therapeutic importance, RhoA has been considered undruggable due to a lack of effective targeted inhibitors.
Purpose of the Study:
- To present a novel protocol for identifying covalent inhibitors targeting the RhoA Cys16 residue.
- To establish a method for validating compound engagement and assessing downstream signaling effects in cancer models.
Main Methods:
- Activity-based protein profiling (ABPP) for initial lead compound identification.
- Mass spectrometry and chemical biology assays for validation of target engagement.
- In vitro and in vivo experiments using cancer cell lines and mouse colorectal cancer (CRC) models to evaluate compound efficacy.
Main Results:
- Successful identification of lead compounds capable of covalently targeting RhoA Cys16.
- Demonstration of target engagement and downstream signaling modulation by the identified inhibitors.
- Validation of the protocol's utility in preclinical cancer models, including CRC.
Conclusions:
- The developed protocol provides a viable strategy for discovering covalent inhibitors against RhoA.
- This approach opens new avenues for targeting RhoA in cancer therapy, addressing a previously undruggable target.
- The findings support the potential of covalent RhoA inhibitors in treating cancers like colorectal cancer.
