Exploiting Synthetic Lethality in Cancer Immunotherapy through Engineered Dual-Specificity T Cells

Here’s the proposed research project:

Jeya Chelliah B.Vsc Ph.D.

Abstract: The concept of synthetic lethality provides a promising avenue for cancer therapy by targeting genetic interactions where the simultaneous impairment of two genes results in cell death, while the impairment of either gene alone does not. This proposal aims to harness the power of synthetic lethality in the context of cancer immunotherapy by developing engineered dual-specificity T cells. These T cells will be designed to recognize and attack cancer cells exhibiting specific pairs of synthetic lethal vulnerabilities, thereby sparing healthy cells and reducing systemic toxicity. This approach combines the specificity of targeted therapy with the potent, adaptable response of the immune system, potentially overcoming the limitations of current immunotherapies, such as resistance and off-target effects.

Background: Cancer cells often acquire mutations that provide growth advantages but can also create specific vulnerabilities, such as dependence on certain metabolic pathways or DNA repair mechanisms. Synthetic lethality exploits these vulnerabilities by targeting the compensatory mechanisms cancer cells use to survive. Meanwhile, immunotherapy, particularly the use of T cells engineered to express chimeric antigen receptors (CAR-T cells), has shown remarkable success in treating certain cancers. However, the development of resistance and the challenge of identifying universal tumor antigens limit their effectiveness.

Objective: To develop and characterize engineered dual-specificity T cells that exploit synthetic lethality for the targeted destruction of cancer cells, improving the efficacy and safety of cancer immunotherapy.

Research Plan and Methodology:

1. Identification of Synthetic Lethal Partners in Cancer Cells:
   • Utilize CRISPR-Cas9 screening to identify pairs of synthetic lethal genes across various cancer cell lines.
   • Bioinformatics analysis to prioritize target pairs based on their specificity to cancer cells and their expression across different cancer types.
2. Design and Construction of Dual-Specificity CAR-T Cells:
   • Engineer T cells with dual-specificity CARs capable of recognizing two distinct antigens associated with the identified synthetic lethal gene pairs.
   • Use advanced gene editing tools to enhance T cell persistence, reduce exhaustion, and improve safety.
3. In Vitro and In Vivo Validation:
   • Assess the cytotoxicity of dual-specificity CAR-T cells against cancer cell lines with the target synthetic lethal vulnerabilities in vitro.
   • Evaluate the efficacy, specificity, and safety of the engineered T cells in mouse models of cancer, focusing on their ability to eradicate tumors and their impact on healthy tissues.
4. Mechanistic Studies and Optimization:
   • Investigate the mechanisms underlying the effectiveness of dual-specificity CAR-T cells, including their persistence, trafficking to tumor sites, and the immune microenvironment’s role.
   • Optimize the design of CAR constructs for enhanced specificity, reduced off-target effects, and improved T cell survival and function.

Significance: This research could revolutionize cancer immunotherapy by introducing a new class of treatment strategies that exploit the concept of synthetic lethality. By targeting cancer-specific vulnerabilities with engineered dual-specificity T cells, this approach aims to increase the specificity and efficacy of cancer immunotherapy, reduce side effects, and overcome the challenges of tumor heterogeneity and resistance. Success in this endeavor would represent a significant step forward in the fight against cancer, offering hope for more effective and personalized treatment options for patients.

Budget and Timeline: A detailed budget and timeline will be provided, covering personnel, equipment, materials, and animal costs for a projected period of 3 years to complete the proposed studies, including milestones for each phase of the project.

Conclusion: The proposed research represents a novel and promising approach to cancer immunotherapy that leverages the principles of synthetic lethality and the power of the immune system. By developing engineered dual-specificity T cells that specifically target cancer cells with minimal impact on normal tissues, this work aims to pave the way for safer, more effective cancer treatments.