RNAi Screen Identifies AXL Inhibition Combined with Cannabinoid WIN55212-2 as a Potential Strategy for Cancer
Feifei Li1, Hang Gong2,3, Xinfei Jia1
1Institute of Pharmacology and Toxicology, Academy of Military Medical Sciences, Academy of Military Sciences, Beijing 100850, China.
Abstract:
Background and objective: Cannabinoids are commonly used as adjuvant cancer drugs to overcome numerous adverse side effects for patients. The aim of this study was to identify the target genes that show a synergistic anti-tumor role in combination with the cannabinoid WIN55212-2 in vitro and in vivo. Methods: A human kinome RNAi library was used to screen the targeted gene that silencing plus WIN55212-2 treatment synergistically inhibited cancer cell growth in an INCELL Analyzer 2000. Cell viability, cell phase arrest and apoptosis were evaluated by MTT and flow cytometry assay. In vivo combined anti-tumor effects and regulatory mechanisms were detected in immunocompromised and immunocompetent mice. Results: Using RNAi screening, we identified the tyrosine receptor kinase AXL as a potential gene whose silencing plus WIN55212-2 treatment synergistically inhibited the proliferation of cancer cells in an INCELL Analyzer 2000. Subsequently, we demonstrated that inhibition of AXL by TP-0903 potentiated the inhibitory role of WIN55212-2 on cellular viability, colony formation and 3D tumor sphere in HCT-8 cells. Meanwhile, TP-0903 plus WIN55212-2 treatment promoted the apoptosis of HCT-8 cells. We then investigated the synergistic anti-tumor effect of TP-0903 and WIN55212-2 using colon cancer cell xenografts in immunocompromised and immunocompetent mice. The in vivo study demonstrated that combined administration of TP-0903 plus WIN55212-2 effectively reduced tumor volume and microvessel density and promoted apoptotic cells of tumor tissues in HCT-8 exogenous mice compared to either TP-0903 or WIN55212-2 treatment alone. Moreover, in addition to tumor suppression, the combination therapy of TP-0903 and WIN55212-2 induced the infiltration of cytotoxic CD8+ T cells and significantly reduced mTOR and STAT3 activation in tumor tissues of C57BL/6J mice bearing MC-38 cells. Conclusions: This study demonstrated that targeting AXL could sensitize cannabinoids to cancer therapy by interfering with tumor cells and tumor-infiltrating CD8+ T cells.
Insights
Targeting AXL synergizes with cannabinoid WIN55212-2 to inhibit cancer growth by promoting apoptosis and T cell infiltration. This combination therapy offers a novel approach to enhance anti-tumor effects in cancer treatment.
Area of Science:
- Oncology
- Pharmacology
- Immunology
Background:
- Cannabinoids are utilized as adjuvant cancer therapies to mitigate adverse effects.
- Identifying synergistic targets with cannabinoids can improve anti-cancer efficacy.
Purpose of the Study:
- To identify genes that synergistically enhance the anti-tumor effects of the cannabinoid WIN55212-2.
- To evaluate the combined therapeutic potential of targeting AXL and WIN55212-2 in vitro and in vivo.
Main Methods:
- RNA interference (RNAi) screening of a human kinome library to identify synergistic targets.
- In vitro assays (MTT, flow cytometry) to assess cell viability, apoptosis, and cell cycle arrest.
- In vivo studies using colon cancer xenografts in immunocompromised and immunocompetent mice.
Main Results:
- AXL (tyrosine receptor kinase) was identified as a synergistic target with WIN55212-2.
- Inhibition of AXL by TP-0903 potentiated WIN55212-2's anti-proliferative and pro-apoptotic effects in HCT-8 cells.
- Combined TP-0903 and WIN55212-2 reduced tumor volume, microvessel density, and increased apoptosis in vivo.
- The combination therapy enhanced cytotoxic CD8+ T cell infiltration and reduced mTOR/STAT3 activation in MC-38 tumor tissues.
Conclusions:
- Targeting AXL sensitizes cancer cells to cannabinoid therapy.
- The combination of AXL inhibition and WIN55212-2 demonstrates significant synergistic anti-tumor activity.
- This approach modulates both tumor cells and the tumor microenvironment, including immune cells.
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02:39lncRNA - Long Non-coding RNAs
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