Homo sapiens
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ABSTRACT:
PROVIDER: PRJNA398304 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Resistance to Checkpoint Blockade Therapy Through Inactivation of Antigen Presentation
| PRJNA398303 | ENA
Project description:Atractylenolide I enhances responsiveness to immune checkpoint blockade therapy by activating tumor antigen presentation
| PRJNA718568 | ENA
Project description:DNA mismatch repair deficient (MMR-d) cancers present an abundance of neoantigens that likely underlies their exceptional responsiveness to immune checkpoint blockade (ICB). However, MMR-d colon cancers that evade CD8+ T cells through loss of Human Leukocyte Antigen (HLA) class I-mediated antigen presentation frequently remain responsive to ICB, suggesting the involvement of other immune effector cells.
2022-11-01 | GSE216534 | GEO
Project description:Immune checkpoint blockade (ICB), notably Programmed Death-1/Programmed Death-Ligand 1 (PD-1/PD-L1) inhibition, has revolutionized the treatment of non-small cell lung cancer (NSCLC). However, durable responses are only observed in a subpopulation of patients. Defective antigen presentation and an immunosuppressive tumor microenvironment can lead to deficient T-cell recruitment and ICB resistance. We evaluated in situ vaccination with CXCL9 and CXCL10-engineered dendritic cells (CXCL9/10-DC) as a novel strategy to overcome resistance to ICB using Lkb1-null murine NSCLC model. We utilized single-cell RNA-seq to evaluate alterations of immune infiltration associated with the new therapy, which combines intratumoral CXCL9/10-DC administration and PD-1 inhibition.
2023-05-22 | GSE232730 | GEO
Project description:The anti-tumor effects of IFNγ are well-known as IFNγ binding to tumor cells increases antigen presentation and can cause cytostatic growth defects. Indeed, the inability of tumors to respond to IFNγ often renders tumors resistant to checkpoint blockade and other immunotherapies reliant on direct T cell cytotoxicity. We performed single-cell RNA-sequencing during virus therapy to get insight into the immune microenvironment of the tumor during treatment.
2023-02-03 | GSE222795 | GEO
Project description:Immune checkpoint blockade (ICB) therapy revolutionized cancer treatment, but many patients with impaired MHC-I expression remain refractory. Histone methylation was involved in anti-tumor immunity of ICB. However, the link between histone methylation and MHC-I regulation and the related mechanisms are poorly understood. Here we show that KDM5A, an H3K4 demethylase that is critical for MHC-I expression and associated antigen presentation capacity, induces robust immune response and enhances ICB efficacy. Mechanistically, KDM5A upregulates IFN-gamma/STAT1-mediated MHC-I expression via directly binding and suppressing Scos1 in tumor cells. The genes encoding the lysosomal cathepsins are recognized and up-regulated by KDM5A, resulting in enhanced antigen-presentation abilities of both tumor cells and dendritic cells. Furthermore, pharmacological enhancing KDM5A improves response to anti-PD-1 therapy. These investigations demonstrate that enhancing KDM5A triggers MHC-associated antigen presentation of both tumor cells and DCs simultaneously to boost antitumor immunity, thus represents a candidate ICB sensitizer.
2024-03-31 | GSE260912 | GEO
Project description:<p>Although immune checkpoint blockade (CPB) leads to prolonged responses in 15-40% of patients with metastatic melanoma, treatment refractory disease and progression after initial response remain major causes of mortality. While predictors of response have been reported, the common mechanisms of both primary and acquired resistance are poorly understood. To identify mechanisms of resistance and examine the evolving landscape in response to CPB, we performed whole exome sequencing (WES), immunohistochemistry (IHC), and RNA-sequencing (RNAseq) of longitudinal tumor biopsies from 17 metastatic melanoma patients treated with various CPB therapies. We found no significant changes in both mutational and neoantigen loads over time between responders and nonresponders. However, we identified abnormalities in one gene, beta-2-microglobulin (<i>B2M</i>), an essential component of MHC Class I antigen presentation, that were present in samples during disease progression but not regression. In total, we identified <i>B2M</i> aberrations in 29.4% of patients, including multiple early frameshift mutations, loss of heterozygosity (LOH) overlapping <i>B2M</i>, and absence of tumor-specific <i>B2M</i> protein expression. Additional defects in the antigen presentation and IFNγ pathways were identified but were not restricted to progressing lesions in our cohort. In two independent cohorts of 105 and 38 melanoma patients treated with ipilimumab (anti-CTLA4) and pembrolizumab (anti-PD1) respectively, we found that <i>B2M</i> LOH was enriched 3-fold in nonresponders (~30%) vs. responders (~10%) and associated with poorer overall survival (log-rank p=0.01, p=0.006). Loss of both copies of <i>B2M</i> was found only in nonresponders. We also found evidence for association of LOH overlapping <i>IFNGR1</i> with poorer overall survival exclusively in the anti-PD1 cohort. Thus, <i>B2M</i> loss is likely a common mechanism of primary and acquired resistance to therapies targeting CTLA4 or PD-1.</p>
| phs001427 | dbGaP
Project description:The anti-tumor effects of IFNγ are well-known as IFNγ binding to tumor cells increases antigen presentation and can cause cytostatic growth defects. Indeed, the inability of tumors to respond to IFNγ often renders tumors resistant to checkpoint blockade and other immunotherapies reliant on direct T cell cytotoxicity. We demonstrate through RNA-sequencing that IFNgR1-/- and STAT1-/- tumors are defective in their response to IFNγ compared to wild-type tumors.
2023-02-06 | GSE212829 | GEO
Project description:Despite immune checkpoint blockades have achieved remarkable success, most patients with solid tumors do not respond or develop resistance, suggesting additional treatment strategies are needed. Concentrated efforts are directed toward revitalizing the IFNγ pathway or amplifying antigen presentation capabilities, alternative mechanisms underlying immune evasion remain poorly understood. Using an unbiased whole-genome in vivo natural selection screen, we identified an uncharacterized role of Monoacylglycerol O-Acyltransferase 1 (Mogat1) as a critical modulator of tumor immune evasion. As tumors progress and expand, they undergo systemic metabolic adaptations to evade immune surveillance. Tumor cells exploit Mogat1 to sequester excess fatty acids into triglycerides, orchestrating metabolic reprogramming that simultaneously fuels tumor growth and creates an immunosuppressive microenvironment. Mogat1 inhibition suppresses tumor growth by promoting T-cell infiltration and cytotoxicity. Remarkably, Mogat1 loss facilitates the circumvention of PD-1 checkpoint blockade resistance. This heightened inflammatory response, characterized by increased interferon sensitivity, circumvents the need for conventional antigen presentation. Our findings reveal a novel lipid metabolism-centered mechanism of immune evasion and offer a potential strategy to enhance cancer immunotherapy efficacy.
2024-08-16 | GSE274902 | GEO
Project description:Only a minority of cancer patients benefit from immune checkpoint blockade therapy. Sophisticated cross-talk among different immune checkpoint pathways as well as interaction pattern of immune checkpoint molecules carried on circulating small extracellular vesicles (sEV) might contribute to the low response rate. Here we demonstrate that PD-1 and CD80 carried on immunocyte-derived sEVs (I-sEV) induce an adaptive redistribution of PD-L1 in tumour cells. The resulting decreased cell membrane PD-L1 expression and increased sEV PD-L1 secretion into the circulation contribute to systemic immunosuppression. PD-1/CD80+ I-sEVs also induce downregulation of adhesion- and antigen presentation-related molecules on tumour cells and impaired immune cell infiltration, thereby converting tumours to an immunologically cold phenotype. Moreover, synchronous analysis of multiple checkpoint molecules, including PD-1, CD80 and PD-L1, on circulating sEVs distinguishes clinical responders from those patients who poorly respond to anti-PD-1 treatment. Altogether, our study shows that sEVs carry multiple inhibitory immune checkpoints proteins, which form a potentially targetable adaptive loop to suppress antitumour immunity.
2024-06-22 | PXD050744 | Pride