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Metabolically fit chimeric antigen receptor (CAR) cells need to be generated for effective CAR immunotherapy. (A) When CAR immune cells reach their target, due to the paucity of nutrients, these cells can become exhausted. This prevents the CAR immune cells from functioning and allows for tumor growth. (B) Metabolically fit CAR immune cells can be generated by modifying the metabolic pathways that endow these immune cells to out-compete cancer cells for nutrients and thus remain active even in the TME for the eradication of cancer cells. (C) Metabolic pathways that are disrupted and can be modified to generate metabolically fit CAR-immune cells.
Source publication
Chimeric antigen receptor (CAR) T cell-based therapies have shown tremendous advancement in clinical and pre-clinical studies for the treatment of hematological malignancies, such as the refractory of pre-B cell acute lymphoblastic leukemia (B-ALL), chronic lymphocytic leukemia (CLL), and large B cell lymphoma (LBCL). However, CAR T cell therapy fo...
Contexts in source publication
Context 1
... studies suggest that cancer cells outcompete T cells for glucose in vivo in cancerous mouse models, therefore preventing the cytokine production that is required for T cells to mount a cellular response against the tumor (Figure 2A) [50,62]. Although further studies are required to understand if this phenomenon is also consistent in human studies. ...
Context 2
... metabolic commitment to a pathway is influenced by both signaling pathways and substrate availability in the microenvironment. These concepts have been applied to CAR T cell therapies for making these cells more effective in killing cancer cells in the solid TME ( Figure 2B). For instance, inhibition of IDO because of increased tryptophan has shown promise for greater success in cancer treatment [66]. ...
Context 3
... instance, inhibition of IDO because of increased tryptophan has shown promise for greater success in cancer treatment [66]. Similarly, checkpoint blockade therapy (anti-PD-1, anti-PD-L1, anti-CTLA-4) corrects nutrient restriction experienced by T cells in a progressing tumor by upregulating CD28 mediated glycolysis ( Figure 2C) [50]. These elegant studies clearly demonstrate that metabolic regulation affects both the function of T cells and their response to low nutrient microenvironments [67]. ...
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Citations
... Previous studies have shown that stably CAR expressing NKs can be achieved through lentiviral and retroviral expressional systems [61]. Others have also reported the use of nonviral expression systems for this purpose [62][63][64]. ...
NK cells are the first sentinels of the immune system that can recognize and eradicate transformed cells. Their activation without a need for additional signaling have attracted great attention on the use of NK cells as a promising option in cancer immunotherapy. However, the large-scale production of NK cells for successful NK cells therapy is a challenge that needs to be tackled. Engineering NK cells to avoid tumor escape and improve their antitumor potency are the other matters of focus that have widely been studied in the recent years. This paper reviews the most recent advances in the stem cell-derived NK cell technology and discusses the potential of the engineered NK cells for clinical applications in cancer immunotherapy.
... Recently, targeting tumor immunity has been regarded as a critical approach to improving therapeutic efficacy [8,9]. Based on the capability of regulating immune cell activation, chimeric antigen receptor T (CAR-T) cells and immune checkpoint inhibitors have achieved impressive efficacy in patients with R/R B-ALL [10,11]. Therefore, molecular mechanisms of tumor immunoregulation associated with tumorigenesis and progression deserve in-depth exploration. ...
Background
As an essential regulator of type I interferon (IFN) response, TMEM173 participates in immune regulation and cell death induction. In recent studies, activation of TMEM173 has been regarded as a promising strategy for cancer immunotherapy. However, transcriptomic features of TMEM173 in B-cell acute lymphoblastic leukemia (B-ALL) remain elusive.
Methods
Quantitative real-time PCR (qRT-PCR) and western blotting (WB) were applied to determine the mRNA and protein levels of TMEM173 in peripheral blood mononuclear cells (PBMCs). TMEM173 mutation status was assessed by Sanger sequencing. Single-cell RNA sequencing (scRNA-seq) analysis was performed to explore the expression of TMEM173 in different types of bone marrow (BM) cells.
Results
The mRNA and protein levels of TMEM173 were increased in PBMCs from B-ALL patients. Besides, frameshift mutation was presented in TMEM173 sequences of 2 B-ALL patients. ScRNA-seq analysis identified the specific transcriptome profiles of TMEM173 in the BM of high-risk B-ALL patients. Specifically, expression levels of TMEM173 in granulocytes, progenitor cells, mast cells, and plasmacytoid dendritic cells (pDCs) were higher than that in B cells, T cells, natural killer (NK) cells, and dendritic cells (DCs). Subset analysis further revealed that TMEM173 and pyroptosis effector gasdermin D (GSDMD) restrained in precursor-B (pre-B) cells with proliferative features, which expressed nuclear factor kappa-B (NF-κB), CD19, and Bruton’s tyrosine kinase (BTK) during the progression of B-ALL. In addition, TMEM173 was associated with the functional activation of NK cells and DCs in B-ALL.
Conclusions
Our findings provide insights into the transcriptomic features of TMEM173 in the BM of high-risk B-ALL patients. Targeted activation of TMEM173 in specific cells might provide new therapeutic strategies for B-ALL patients.
... Commercial approval of several CAR T cell therapies by the FDA [277] T cells are more suitable for bioengineering by classical viral vector transduction [257] No need for cells of autologous origin [172] Less prone to GVHD [172] CAR designs and metabolic fitness 4-1BB-containing CAR: OXPHOS metabolism [75] and longer in vivo persistence [72] CD28-containing CAR: glycolytic metabolism [75] and shorter in vivo persistence [72] NKG2D-expressing CAR resistant to the immune and metabolic suppressor TGFβ drives MDSCs clearance and better tumor burden control of CAR T cells targeting neuroblastoma in mice [261]. ...
Nutritional interventions are investigated in the context of non-communicable diseases such as cancer. Dietary regimens such as caloric restriction, fasting, ketogenic and protein-restricted diets have shown benefits to control tumor progression. Indeed, we have previously reported the protective effect of an isocaloric diet partially reduced in protein in several cancer mouse models. Beyond a stronger anticancer immunosurveillance dependent on cytotoxic T cells, the low protein diet limited tumor growth in an IRE1α-dependent manner.Inositol-requiring enzyme 1α (IRE1α) is the most evolutionally conserved ER (endoplasmic reticulum) stress sensor induced as part of the Unfolded Protein Response (UPR). The UPR is activated by accumulation of misfolded proteins in the ER, lipidic disturbances in the ER membrane, hypoxia and nutrient deprivation. IRE1α activates downstream targets via its endoribonuclease activity resulting in XBP1 splicing as well as degradation of RNAs by a process known as the Regulated IRE1-Dependent Decay (RIDD). While XBP1 splicing recovers cellular homeostasis, massive RIDD induction leads to apoptosis under chronic ER stress.The IRE1α signaling has been described to play dual roles in most hallmarks of cancer. While the IRE1α-XBP1 axis in tumor cells supports tumor progression in several solid and liquid oncogenic malignancies, the IRE1α-RIDD branch has been suggested as tumor-suppressive in glioblastoma. Since our previous findings showed that IRE1 is implicated in the tumor-protective effects of a low protein diet, we investigated the effect of the exogenous expression of IRE1 in tumor cells implanted in immunocompetent mice.We found that overexpression of IRE1 and self-induction of its full RNAse activity was detrimental for subcutaneous tumor growth of colorectal and Lewis lung carcinomas. Tumors with higher IRE1 activity were characterized by active IRE1α-XBP1 and IRE1α-RIDD branches, a higher anticancer immunosurveillance and tumor cells undergoing apoptosis. The enhanced anti-cancer immune response elicits upon IRE1α overexpression was mainly dependent on T cell-mediated-cytotoxicity. In conclusion, our findings support the notion that IRE1α with a full RNAse activity can have tumor-suppressive roles.
... The currently approved FDA therapies Kymriah and Yescarta belong to this second-generation CAR-T cells. The experience gained from the application of secondgeneration CAR-T cells highlighted the relevance of the costimulatory molecule on the function and fate of the engineered cells within the TME (85). The addition of the 4-1BB (CD137) domain to CAR constructs promoted the induction of CD8 + T cells with increased respiratory capacity and heightened mitochondrial biogenesis, two characteristics of the least differentiated memory T cells (24,25,86). ...
... Third-generation CARs incorporated a second co-stimulatory signaling domain to achieve greater functional potency ( Figure 3C) (90,91). For example, the addition of the CD28 and OX40 domains to a CD3z chain leads to the sustained activation, proliferation, and effector function of resting T cells through the NFkB signaling pathway (85). Furthermore, ICOS-dependent signaling in CAR-T cells has been shown to result in an enhanced cell survival following the ACT. ...
... Specific metabolic and epigenetic changes must occur in cells in order to proliferate and differentiate. As can be seen, metabolism is intimately linked to cell activation, proliferation, migration, and function, and therefore to the very fate of T cells (85,161,162). ...
Adoptive cell therapy with T cells reprogrammed to express chimeric antigen receptors
(CAR-T cells) has been highly successful in patients with hematological neoplasms.
However, its therapeutic benefits have been limited in solid tumor cases. Even those
patients who respond to this immunotherapy remain at risk of relapse due to the short-term persistence or non-expansion of CAR-T cells; moreover, the hostile tumor
microenvironment (TME) leads to the dysfunction of these cells after reinfusion. Some
research has shown that, in adoptive T-cell therapies, the presence of less differentiated T-cell subsets within the infusion product is associated with better clinical outcomes. Naive
and memory T cells persist longer and exhibit greater antitumor activity than effector T
cells. Therefore, new methods are being studied to overcome the limitations of this
therapy to generate CAR-T cells with these ideal phenotypes. In this paper, we review the
characteristics of T-cell subsets and their implications in the clinical outcomes of adoptive
therapy with CAR-T cells. In addition, we describe some strategies developed to
overcome the reduced persistence of CAR T-cells and alternatives to improve this
therapy by increasing the expansion ability and longevity of modified T cells. These
methods include cell culture optimization, incorporating homeostatic cytokines during the
expansion phase of manufacturing, modulation of CAR-T cell metabolism, manipulating
signaling pathways involved in T-cell differentiation, and strategies related to CAR
construct designs.
... The limited efficacy in the treatment of solid tumors observed in CAR-T cells in vivo may pose a similar challenge for CAR-NK cells as studies on allogeneic, activated NK cells imply that they face cellular exhaustion and poor infiltration into tumor sites (14,(135)(136)(137). To overcome immune suppression in the TME, additional arming of immune cells through genetic engineering is pushed for, e.g., by genetic ablations (138,139) or metabolic reprogramming of NK cells (140,141). ...
Cancer immunotherapies utilize the capabilities of the immune system to efficiently target malignant cells. In recent years, chimeric antigen receptor (CAR) equipped T cells showed promising results against B cell lymphomas. Autologous CAR-T cells require patient-specific manufacturing and thus extensive production facilities, resulting in high priced therapies. Along with potentially severe side effects, these are the major drawbacks of CAR-T cells therapies. Natural Killer (NK) cells pose an alternative for CAR equipped immune cells. Since NK cells can be safely transferred from healthy donors to cancer patients, they present a suitable platform for an allogeneic “off-the-shelf” immunotherapy. However, administration of activated NK cells in cancer therapy has until now shown poor anti-cancer responses, especially in solid tumors. Genetic modifications such as CARs promise to enhance recognition of tumor cells, thereby increasing anti-tumor effects and improving clinical efficacy. Although the cell biology of T and NK cells deviates in many aspects, the development of CAR-NK cells frequently follows within the footsteps of CAR-T cells, meaning that T cell technologies are simply adopted to NK cells. In this review, we underline the unique properties of NK cells and their potential in CAR therapies. First, we summarize the characteristics of NK cell biology with a focus on signaling, a fine-tuned interaction of activating and inhibitory receptors. We then discuss why tailored NK cell-specific CAR designs promise superior efficacy compared to designs developed for T cells. We summarize current findings and developments in the CAR-NK landscape: different CAR formats and modifications to optimize signaling, to target a broader pool of antigens or to increase in vivo persistence. Finally, we address challenges beyond NK cell engineering, including expansion and manufacturing, that need to be addressed to pave the way for CAR-NK therapies from the bench to the clinics.
... Commercial approval of several CAR T cell therapies by the FDA [277] T cells are more suitable for bioengineering by classical viral vector transduction [257] No need for cells of autologous origin [172] Less prone to GVHD [172] CAR designs and metabolic fitness 4-1BB-containing CAR: OXPHOS metabolism [75] and longer in vivo persistence [72] CD28-containing CAR: glycolytic metabolism [75] and shorter in vivo persistence [72] NKG2D-expressing CAR resistant to the immune and metabolic suppressor TGFβ drives MDSCs clearance and better tumor burden control of CAR T cells targeting neuroblastoma in mice [261]. ...
Chimeric antigen receptor (CAR) T and CAR NK cell therapies opened new avenues for cancer treatment. Although original successes of CAR T and CAR NK cells for the treatment of hematological malignancies were extraordinary, several obstacles have since been revealed, in particular their use for the treatment of solid cancers. The tumor microenvironment (TME) is competing for nutrients with T and NK cells and their CAR-expressing counterparts, paralyzing their metabolic effective and active states. Consequently, this can lead to alterations in their anti-tumoral capacity and persistence in vivo. High glucose uptake and the depletion of key amino acids by the TME can deprive T and NK cells of energy and building blocks, which turns them into a state of anergy, where they are unable to exert cytotoxic activity against cancer cells. This is especially true in the context of an immune-suppressive TME. In order to re-invigorate the T, NK, CAR T and CAR NK cell-mediated antitumor response, the field is now attempting to understand how metabolic pathways might change T and NK responses and functions, as well as those from their CAR-expressing partners. This revealed ways to metabolically rewire these cells by using metabolic enhancers or optimizing pre-infusion in vitro cultures of these cells. Importantly, next-generation CAR T and CAR NK products might include in the future the necessary metabolic requirements by improving their design, manufacturing process and other parameters. This will allow the overcoming of current limitations due to their interaction with the suppressive TME. In a clinical setting, this might improve their anti-cancer effector activity in synergy with immunotherapies. In this review, we discuss how the tumor cells and TME interfere with T and NK cell metabolic requirements. This may potentially lead to therapeutic approaches that enhance the metabolic fitness of CAR T and CAR NK cells, with the objective to improve their anti-cancer capacity.
... Poznanski et al. cultured the expanded NK cells using IL-21-expressing feeder cells which have metabolic adaptations and can harbour features to better sustain function in the TME [39]. Simultaneously, it was reported that efficient immunotherapies could be developed when metabolism of chimeric antigen receptor NK cells was engineered [40]. Immunometabolism represents an attractive target; thus, it is important to understand how GCMSCs affect NK cell metabolism and function. ...
Introduction:
The dysfunction of natural killer (NK) cells has been widely reported in malignancies, including in solid tumours. Gastric cancer mesenchymal stem cells (GCMSCs) are one of the vital elements of stromal cells in the tumour environment (TME) which possess immunosuppressive activity. This study aimed to determine whether GCMSCs are involved in the inhibition of NK cell immune function and explore its underlying mechanism.
Material and methods:
CD107a and perforin expression of GCMSCs conditioned medium (GCMSCs-CM)-primed NK cells were detected by flow cytometry. To determine NK cell cytotoxicity, the CytoTox96 Non-Radioactive Cytotoxicity Assay kit was used. Glucose uptake and lactate production assay were performed to evaluate the metabolism state of NK cells treated with GCMSCs-CM. The expression of FBP1 in NK cells was analysed by immunoblotting.
Results:
GCMSCs inhibited the degranulation capacity, perforin production and cytotoxicity of NK cells. GCMSCs-CM restrained NK cell glucose uptake and lactate production, thus weakening their glycolytic metabolism. FBP1 expression of NK cells was upregulated in the presence of GCMSCs-CM. Using FBP1 inhibitor could reverse the dysfunctional state of NK cells.
Conclusions:
This study indicated that GCMSCs could exert immunosuppressive effects on NK cells by up-regulating FBP1 expression, opening up new avenues for NK cell-based GC immunotherapy.
Advancements in chimeric antigen receptor engineered T-cell (CAR-T) therapy have revolutionized treatment for several cancer types over the past decade. Despite this success, obstacles including the high price tag, manufacturing complexity, and treatment-associated toxicities have limited the broad application of this therapy. Chimeric antigen receptor engineered natural killer cell (CAR-NK) therapy offers a potential opportunity for a simpler and more affordable “off-the-shelf” treatment, likely with fewer toxicities. Unlike CAR-T, CAR-NK therapies are still in early development, with few clinical trials yet reported. Given the challenges experienced through the development of CAR-T therapies, this review explores what lessons we can apply to build better CAR-NK therapies. In particular, we explore the importance of optimizing the immunochemical properties of the CAR construct, understanding factors leading to cell product persistence, enhancing trafficking of transferred cells to the tumor, ensuring the metabolic fitness of the transferred product, and strategies to avoid tumor escape through antigen loss. We also review trogocytosis, an important emerging challenge that likely equally applies to CAR-T and CAR-NK cells. Finally, we discuss how these limitations are already being addressed in CAR-NK therapies, and what future directions may be possible.
Activated effector T cells induce pro-inflammatory responses in rheumatoid arthritis (RA) which then lead to inflammation of the joints. In this report, we demonstrate that polymeric nanoparticles with alpha keto-glutarate (aKG) in their polymer backbone (termed as paKG NPs) modulate T cell responses in vitro and in vivo. Impressively, a low dose of only three administrations of methotrexate, a clinically and chronically administered drug for RA, in conjunction with two doses of paKG NPs, reversed arthritis symptoms in collagen-induced arthritis (CIA) mice. This was further followed by significant decreases in pro-inflammatory antigen-specific T helper type 17 (TH17) responses and a significant increase in anti-inflammatory regulatory T cell (TREG) responses when CIA treated splenic cells were isolated and re-exposed to the CIA self-antigen. Overall, this study supports the concurrent and short term, low dose of paKG NPs and methotrexate for the reversal of RA symptoms.
Recently, novel types of immunotherapies such as CAR-T cell therapy demonstrated efficacy in leukemia, lymphoma, and multiple myeloma [1–3]. CD19 and BCMA-CAR-T cell therapies were approved by FDA to treat patients with the above diseases. There are still several challenges for CAR-T cell therapy, including safe and effective antigen targets for solid tumors, overcoming a suppressive tumor microenvironment, and loss of antigen expression, among others [4,5][...]
