Optimizing CAR T therapy via metabolic engineering for thetreatment of GBM

PROJECT SUMMARY AND ABSTRACT Significance: Glioblastoma (GBM) is an extremely devastating disease with reported median survivals ranging from 13 to 73 months and 5-year survivals of less than 20% in children and about 15 months with less than 5% 5-year survival rate for adult patients. Cancer immunotherapy using chimeric antigen receptor (CAR) modified T

cells is a promising treatment, however its efficacy in GBM has been limited. Hypothesis: We hypothesize that the fierce competition for nutrients within the tumor microenvironment, especially glucose, between tumor cells and the immune system, imposes an abundant metabolic pressure to CAR T cells dampening their effector function and intratumoral infiltration, expansion, and persistence.

Objective: The goal of this study is to validate a new strategy to overcome this metabolic imbalance and provide a competitive advantage to CAR T cells over tumor cells. We propose to improve CAR T cell therapy by enhancing metabolic fitness to outcompete GBM cells for nutrients like glucose. Methods: Our approach will be to directly target the first step of glucose metabolism (i.e., uptake) by permanent

overexpression of GLUT1 or GLUT3 and generating the following CAR T cells: CD70CAR.G1 and CD70CAR.G3. The murine model of glioma KR158B, derived from Nf1;Trp53 mutant mouse, that we engineered to express CD70 as well as CD70 expressing human GBM patient-derived cell lines will be used for the following aims:

Specific Aims 1. Investigate the phenotypic and functional characteristics of metabolically modified CD70CAR T cells, 2. Evaluate in vivo the metabolic TME of animals treated with CD70CAR.G1 or CD70CAR.G3, 3. Examine the safety and anti-tumor efficacy of CD70CAR.G1 or CD70CAR.G3.