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In Vivo Inhibition of MicroRNA to Decrease Tumor Growth in Mice
Published on: August 23, 2019
Targeting the α4-α5 dimerization interface of K-RAS inhibits tumor formation in vivo
Imran Khan1,2,3,4, Russell Spencer-Smith1,2, John P O'Bryan5,6,7,8
1Department of Pharmacology, University of Illinois Cancer Center, University of Illinois at Chicago, Chicago, IL, 60612, USA.
Abstract:
RAS genes are the most commonly mutated oncogenes in human cancers. Despite tremendous efforts over the past several decades, however, RAS-specific inhibitors remain elusive. Thus, targeting RAS remains a highly sought-after goal of cancer research. Previously, we have reported a new approach to inhibit RAS-dependent signaling and transformation in vitro by targeting the α4-α5 dimerization interface with a novel RAS-specific monobody termed NS1. Expression of NS1 inhibits oncogenic K-RAS and H-RAS signaling and transformation in vitro. Here, we evaluated the efficacy of targeting RAS dimerization as an approach to inhibit tumor formation in vivo. Using a doxycycline (DOX)-regulated NS1 expression system, we demonstrate that DOX-induced NS1 inhibited oncogenic K-RAS-driven tumor growth in vivo. Furthermore, we observed context-specific effects of NS1 on RAS-mediated signaling in 2D vs 3D growth conditions. Finally, our results highlight the potential therapeutic efficacy of targeting the α4-α5 dimerization interface as an approach to inhibit RAS-driven tumors in vivo.
Insights
Targeting RAS dimerization with the NS1 monobody effectively inhibited oncogenic K-RAS-driven tumor growth in vivo. This approach shows promise for developing new cancer therapies against RAS-driven tumors.
Area of Science:
- Oncology
- Molecular Biology
- Drug Discovery
Background:
- RAS genes are frequently mutated in human cancers, making them critical targets for cancer therapy.
- Developing effective RAS-specific inhibitors has been challenging for decades.
- Targeting RAS signaling pathways remains a key goal in cancer research.
Purpose of the Study:
- To evaluate the in vivo efficacy of targeting the RAS α4-α5 dimerization interface using the NS1 monobody.
- To assess the potential of NS1 as a therapeutic strategy against RAS-driven tumors.
- To investigate the context-specific effects of NS1 on RAS signaling.
Main Methods:
- Utilized a doxycycline (DOX)-regulated NS1 expression system in vivo.
- Assessed tumor growth inhibition in oncogenic K-RAS-driven tumor models.
- Analyzed RAS-mediated signaling in both 2D and 3D cell culture conditions.
Main Results:
- DOX-induced NS1 expression significantly inhibited oncogenic K-RAS-driven tumor growth in vivo.
- NS1 demonstrated context-specific effects on RAS-mediated signaling depending on growth conditions (2D vs. 3D).
- The study confirmed the in vitro findings of NS1 inhibiting K-RAS and H-RAS signaling.
Conclusions:
- Targeting the RAS α4-α5 dimerization interface with NS1 is a viable strategy for inhibiting in vivo tumor formation.
- NS1 exhibits therapeutic potential for treating RAS-driven cancers.
- Understanding context-specific signaling is crucial for NS1 efficacy in different tumor microenvironments.
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