Modulation of intracellular kinase signaling to improve TIL stemness and function for adoptive cell therapy

Abstract

Introduction Adoptive cellular therapy with tumor‐infiltrating lymphocytes (TIL) has demonstrated promising clinical benefits in several solid tumors, but the efficacy of this therapy might be compromised by the “prone‐to‐exhaustion” phenotype of TIL and poor persistence in vivo. This calls for a robust expansion process to produce a large number of cells for clinical usage while at the same time maintaining favorable anti‐tumor function and memory phenotype. Previous studies showed that the PI3K‐AKT signaling pathway plays a key role in the regulation of T cell activation, differentiation and memory formation. Method We modulated the PI3K‐AKT pathway in TIL isolated from cervical and ovarian cancer by application of AKT or PI3K inhibitors or CRISPR knockout of AKT1 and/or AKT2, and characterized their effects on TIL phenotype and effector function. Mechanistic study was further performed with RNA‐seq analysis of AKT1/2 KO TIL in comparison to control TIL. Result The inhibition of either PI3K or AKT led to an increase in the population of effector CD8 + T cells with upregulation of activation markers, elevated CD39 − CD69 − memory T cells, and significantly enhanced cytotoxicity when cocultured with tumor cell lines and patient‐derived tumor samples. Moreover, dual knockout of AKT1 and AKT2 largely phenocopies the functional impact of AKT or PI3K inhibition on TIL. This result was further validated by RNA‐seq analysis indicating that AKT1/2 ablation primarily regulates T cell differentiation and function‐related programs. Conclusion Modulation of PI3K‐AKT signaling represents a promising strategy to enhance TIL stemness and cytotoxicity and improve the clinical outcome of current TIL‐based therapy to treat solid tumors.

ARHGAP21 Is Involved in the Carcinogenic Mechanism of Cholangiocarcinoma: A Study Based on Bioinformatic Analyses and Experimental Validation

“…Meanwhile, the accumulated research indicates that the PI3K/Akt pathway is involved in cancer immunotherapy. The regulation of the PI3K/Akt signaling pathway can change the cytotoxicity of tumor-infiltrating cells [ 31 ]. Gao et al proposed that the restraint of the PI3K/Akt pathway can inhibit the expression of PD-L1 and enhance the effect against tumors in lung cancer [ 32 ].…”

Novel strategies to improve efficacy of treatment with tumor-infiltrating lymphocytes (TILs) for patients with solid cancers

“…Two strategies have been used so far, either by growing TILs in the presence of AKT1/2 inhibitors or by knocking out AKT1/2 using CRISPR/ Cas in TILs. With both methods, TIL products with less features of dysfunction, with stem cell memory characteristics and with improved killing capacity have been generated, without compromising TIL expansion [49][50][51][52][53].…”

Towards next‐generation TIL therapy: TILs enriched in neoepitope‐specific T cells

“… 23 In addition, TILs can be re‐programmed towards memory and stemness by direct genetic engineering. 22 , 24 Importantly, the timing and combinations of manufacturing‐compatible interventions, either pharmacological or genetic, remain to be investigated.…”

“…Given the selective stimulation of neoantigen‐specific T cells with NeoScreen, methods to optimize TILs’ stemness will be fundamental to enhance the clinical benefit of TIL therapy. Among the many possible metabolic interventions (Figure 1) are the addition of memory cytokines during T cell expansion, 21 the inhibition of signalling pathways leading to T cell effector differentiation 22 or the prevention of T cell activation‐induced cell death by supplementation with anti‐oxidants 23 . In addition, TILs can be re‐programmed towards memory and stemness by direct genetic engineering 22,24 .…”

“…Among the many possible metabolic interventions (Figure 1) are the addition of memory cytokines during T cell expansion, 21 the inhibition of signalling pathways leading to T cell effector differentiation 22 or the prevention of T cell activation‐induced cell death by supplementation with anti‐oxidants 23 . In addition, TILs can be re‐programmed towards memory and stemness by direct genetic engineering 22,24 . Importantly, the timing and combinations of manufacturing‐compatible interventions, either pharmacological or genetic, remain to be investigated.…”