Project description:Glutamine-dependence of cancer cells reduces local glutamine availability, which hinders anti-tumor T-cell functionality and facilitates immune evasion. We thus speculated that glutamine deprivation might be limiting efficacy of CAR T-cell therapies in cancer patients. We have seen that antigen-specific T cells are unable to proliferate or produce IFN-γ in response to antigen stimulation when glutamine concentration is limited. Using multiple myeloma (MM) as a glutamine-dependent disease model, we found that murine CAR-T cells selectively targeting BCMA in MM cells were sensitive to glutamine deprivation. However, CAR-T cells engineered to increase glutamine uptake by expression of the glutamine transporter Asct2 exhibited enhanced proliferation and responsiveness to antigen stimulation, increased production of IFN-, and heightened cytotoxic activity, even under conditions of low glutamine concentration. Mechanistically, Asct2 overexpression reprogrammed CAR-T cell metabolic fitness, improving basal oxygen consumption rate and glycolytic function that enhanced CAR-T cell persistence in vivo. Accordingly, expression of Asct2 increased the efficacy of BCMA CAR-T cells in syngeneic and genetically-engineered mouse models of MM, which prolonged mouse survival. In patients, reduced expression of Asct2 by MM cells predicted poor outcome to combined immunotherapy and BCMA-CAR T-cell therapy. Our results indicate that reprogramming glutamine metabolism may enhance anti-tumor CAR T-cell functionality in multiple myeloma. This approach may also be effective for other cancers that depend on glutamine as a key energy source and metabolic hallmark.
Project description:To investigate the function of SLC1A5 in glioma cells, we establishedT98G cell line in which SLC1A5 has been knocked down by shRNA.
Project description:Tumor cells often evade immune pressure via metabolic reprogramming, yet the key metabolic regulators orchestrating this process remain poorly defined. Here, using in vivo metabolic CRISPR screening under distinct immune pressures, we identified tumor cell–derived solute carrier family 1 member 5 (SLC1A5) as a critical metabolic node that sustains an immunosuppressive tumor microenvironment (TME). SLC1A5-mediated glutamine metabolism in tumor cells modulates CD8 T cell infiltration and effector function, reshaping tumor response to immune checkpoint blockade therapy. Mechanistically, glucose deprivation up-regulated SLC1A5 isoforms in tumor cells, enhancing glutamine uptake and metabolic flux remodeling to reset intracellular metabolic homeostasis. This program suppressed inflammatory tumor cell differentiation characterized by cyclic GMP-AMP synthase–stimulator of interferon genes (cGAS–STING) pathway activation, reducing interferon-β secretion and impairing CD8 immunity. These findings define a glutamine-fueled metabolic program as a critical barrier to tumor immunogenicity, positioning SLC1A5 as a metabolic immune checkpoint with therapeutic relevance.
Project description:Tumor cells often evade immune pressure via metabolic reprogramming, yet the key metabolic regulators orchestrating this process remain poorly defined. Here, using in vivo metabolic CRISPR screening under distinct immune pressures, we identified tumor cell–derived solute carrier family 1 member 5 (SLC1A5) as a critical metabolic node that sustains an immunosuppressive tumor microenvironment (TME). SLC1A5-mediated glutamine metabolism in tumor cells modulates CD8 T cell infiltration and effector function, reshaping tumor response to immune checkpoint blockade therapy. Mechanistically, glucose deprivation up-regulated SLC1A5 isoforms in tumor cells, enhancing glutamine uptake and metabolic flux remodeling to reset intracellular metabolic homeostasis. This program suppressed inflammatory tumor cell differentiation characterized by cyclic GMP-AMP synthase–stimulator of interferon genes (cGAS–STING) pathway activation, reducing interferon-β secretion and impairing CD8 immunity. These findings define a glutamine-fueled metabolic program as a critical barrier to tumor immunogenicity, positioning SLC1A5 as a metabolic immune checkpoint with therapeutic relevance.
Project description:Tumor cells often evade immune pressure via metabolic reprogramming, yet the key metabolic regulators orchestrating this process remain poorly defined. Here, using in vivo metabolic CRISPR screening under distinct immune pressures, we identified tumor cell–derived solute carrier family 1 member 5 (SLC1A5) as a critical metabolic node that sustains an immunosuppressive tumor microenvironment (TME). SLC1A5-mediated glutamine metabolism in tumor cells modulates CD8 T cell infiltration and effector function, reshaping tumor response to immune checkpoint blockade therapy. Mechanistically, glucose deprivation up-regulated SLC1A5 isoforms in tumor cells, enhancing glutamine uptake and metabolic flux remodeling to reset intracellular metabolic homeostasis. This program suppressed inflammatory tumor cell differentiation characterized by cyclic GMP-AMP synthase–stimulator of interferon genes (cGAS–STING) pathway activation, reducing interferon-β secretion and impairing CD8 immunity. These findings define a glutamine-fueled metabolic program as a critical barrier to tumor immunogenicity, positioning SLC1A5 as a metabolic immune checkpoint with therapeutic relevance.
Project description:In this study, we found that H3K9ac level were reduced both in vitro (Slc1a5 knockdown VSMCs) and in vivo (Slc1a5 knockout mice). To further investigate the potential functional significance that SLC1A5-mediated H3K9ac contributed to the pathogenesis of aortic aneurysm and dissection (AAD), we performed genome-wide cleavage under targets and tagmentation (CUT&Tag) analysis to identify candidate genes regulated by H3K9ac (CST, 9649S) in Slc1a5 knockdown mouse VSMCs. Following CUT&Tag, H3K9ac associated DNAs were amplified using non-biased conditions, labeled, and sequenced with Illumina novaseq Xplus.
Project description:Glutamine is carried into and out of cells by glutamine transporters such as SLC1, SLC7 and SLC38 families, and cytoplasmic glutamine subsequently catabolized to glutamate that provides biosynthetic precursors. To identify the candidate glutamine transporters or glutamate metabolism regulators that contributed to the pathogenesis of Aortic aneurysm and dissection (AAD), we used RNA sequencing analysis in Ang II perfusion-induced AAD in Apoe-/- mice and discovered that several key genes associated with glutamine transports and metabolism were considerably reduced in AAD, particularly Slc1a5.