MLLT6 maintains PD‐L1 expression and mediates tumor immune resistance
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA603767 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| SRR10985259.fastq.gz | Fastqsanger.gz | |||
| SRR10985260.fastq.gz | Fastqsanger.gz | |||
| SRR10985261.fastq.gz | Fastqsanger.gz | |||
| SRR10985262.fastq.gz | Fastqsanger.gz | |||
| SRR10985263.fastq.gz | Fastqsanger.gz |
Items per page: 5 1 - 5 of 16 |
Similar Datasets
Project description:We present a CRISPR-Cas9 screen in human cancer cells to identify genes that confers tumors with the ability to evade the cytotoxic effects of the immune system. We discovered that the transcriptional regulator MLLT6 (AF17) is required for PD-L1 cell surface presentation and protein expression in multiple cancer types and MLLT6 depletion alleviates suppression of CD8+ cytotoxic T cell-mediated cytolysis. Furthermore, cancer cells lacking MLLT6 exhibit impaired STAT1 signaling and are insensitive to interferon gamma induced stimulation of IDO1, GBP5, CD74 and MHC class II genes, while maintaining MHC class I gene expression. Collectively, our findings establish MLLT6 as a regulator of oncogenic and interferon gamma associated immune resistance
2020-10-16 | GSE144484 | GEO
Project description:Tumor cells subvert immune surveillance by harnessing signals from immune checkpoints to acquire immune resistance. The protein PD-L1 is an important component in this process, and inhibition of PD-L1 elicits durable anti-tumor responses in a broad spectrum of cancers. However, immune checkpoint inhibition that target known pathways is not universally effective. A better understanding of the genetic repertoire underlying these processes is necessary to expand our knowledge in tumor immunity and to facilitate identification of alternative targets. Here, we present a CRISPR/Cas9 screen in human cancer cells to identify genes that confer tumors with the ability to evade the cytotoxic effects of the immune system. We show that the transcriptional regulator MLLT6 (AF17) is required for efficient PD-L1 protein expression and cell surface presentation in cancer cells. MLLT6 depletion alleviates suppression of CD8+ cytotoxic T cell-mediated cytolysis. Furthermore, cancer cells lacking MLLT6 exhibit impaired STAT1 signaling and are insensitive to interferon-γ-induced stimulation of IDO1, GBP5, CD74, and MHC class II genes. Collectively, our findings establish MLLT6 as a regulator of oncogenic and interferon-γ-associated immune resistance.
| S-EPMC7726806 | biostudies-literature
Project description:To identify which E3 ligases ubiquitinate PD-L1, we overexpressed PD-L1-Flag in HEK293 cells and used anti-Flag magnetic beads to pull down PD-L1 from cell lysates. The interacting proteins were then analyzed by mass spectrometry, revealing that three E3 ligases interact with PD-L1.
2025-05-07 | PXD057691 | Pride
Project description:Blocking the PD-1/PD-L1 immunosuppressive pathway has shown promise in the treatment of certain cancers including melanoma. This study investigates differences in the gene expression profiles of human melanomas that do or do not display the immunosuppressive protein PD-L1. Further understanding of genes expressed within the tumor microenvironment of PD-L1+ tumors may lead to improved rationally designed treatments. Gene expression profiling was performed on total RNA extracted by laser capture microdissection from 11 archived formalin-fixed paraffin-embedded (FFPE) melanoma specimens, 5 of which were PD-L1 positive and 6 PD-L1 negative. Details of the design, and the gene signatures found are given in the paper associated with this GEO Series: Janis M. Taube, Geoffrey D. Young, Tracee L. McMiller, Shuming Chen, January T. Salas, Theresa S. Pritchard, Haiying Xu, Alan K. Meeker, Jinshui Fan, Chris Cheadle, Alan E. Berger, Drew M. Pardoll, and Suzanne L. Topalian, Differential expression of immune-regulatory genes associated with PD-L1 display in melanoma: implications for PD-1 pathway blockade, Clin Cancer Res 2015, in press.
2015-05-01 | E-GEOD-65041 | biostudies-arrayexpress
Project description:Disrupting PD-1/PD-L1 interaction rejuvenates antitumor immunity. Clinical successes by blocking PD-1/PD-L1 binding have grown across wide-ranging cancer histologies, but innate therapy resistance is evident in the majority of treated patients1. Cancer cells can express robust surface levels of PD-L1 to tolerize tumor-specific T cells, but regulation of PD-L1 protein levels in the cancer cell is poorly understood. Quasi-mesenchymal tumor cells up-regulate PD-L1/L2 and induce an immune-suppressive microenvironment, including expansion of M2-like macrophages and regulatory T cells and exclusion of CD8+ T-cell infiltration2. Targeted therapy, including MAPK inhibitor therapy in melanoma, leads to quasi-mesenchymal transitions and resistance3, and both MAPK inhibitor treatment and mesenchymal signatures are associated with innate anti-PD-1 resistance4,5. Here we identify ITCH as an E3 ligase that downregulates tumor cell-surface PD-L1/L2 in PD-L1/L2-high cancer cells, including MAPK inhibitor-resistant melanoma, and suppresses acquired MAPK inhibitor resistance in and only in immune-competent mice. ITCH interacts with and poly-ubiquitinates PD-L1/L2, and ITCH deficiency increases cell-surface PD-L1/L2 expression and reduces T cell activation. Mouse melanoma tumors grow faster with Itch knockdown only in syngeneic hosts but not in immune-deficient mice. MAPK inhibitor therapy induces tumor cell-surface PD-L1 expression in murine melanoma, recapitulating the responses of clinical melanoma3, and this induction is more robust with Itch knockdown. Notably, suppression of ITCH expression first elicits a shift toward an immune-suppressive microenvironment and then accelerates resistance development. These findings collectively identify ITCH as a critical negative regulator of PD-L1 tumor cell-surface expression and provide insights into previously unexplained role of PD-L1 in adaptive resistance to therapy.
2022-03-31 | MSV000089180 | MassIVE
Project description:Thirty-eight tumors from 17 patients treated with BRAF inhibitor (n=12) or combination BRAF/MEK inhibitors (n=5) with known PD-L1 expression were analyzed. RNA expression arrays were performed on all pre-treatment (PRE, n=17), early during treatment (EDT, n=8) and progression (PROG, n=13) biopsies. HLA-A/HLA-DPB1 expression was assessed by immunohistochemistry (IHC). Gene set enrichment analysis (GSEA) of PRE, EDT and PROG melanomas revealed that transcriptome signatures indicative of immune cell activation were strongly positively correlated with PD-L1 staining. In contrast, MAPK signaling and canonical Wnt/-ß-catenin activity were negatively associated with PD-L1 melanoma expression. The expression of PD-L1 and immune activation signatures did not simply reflect the degree or type of immune cell infiltration, and was not sufficient for tumor response to MAPK inhibition.
2017-07-01 | GSE99898 | GEO
Project description:Programmed cell death 1 ligand 1 (PD-L1) is known to suppress immune system and to be an unfavorable prognostic factor in ovarian cancer. The purpose of this study was to elucidate the function of PD-L1 in peritoneal dissemination. Tumor cell lysis by CTLs was attenuated when PD-L1 on tumor cells was overexpressed and promoted when it was silenced. PD-L1 overexpression also inhibited gathering and degranulation of CTLs. Gene expression profile of mouse CTLs caused by PD-L1-overexpressing ovarian cancer was related to human CTLs exhaustion. In mouse ovarian cancer dissemination models, depleting PD-L1 expression on tumor cells resulted in inhibited tumor growth in the peritoneal cavity and prolonged survival. Restoring immune function by inhibiting immune-suppressive factors such as PD-L1 may be a promising therapeutic strategy for peritoneal dissemination. Genome-wide transcriptional changes in OT-1 mouse CD8+ T cells that were co-incubated with OVA peptide-loaded ID8 mouse ovarian cancer cell lines. CTLs from 4 mice were devided into 2 groups, and co-incubated with PD-L1-overexpressed ID8 or PD-L1-depleted ID8.
2012-07-09 | E-GEOD-39205 | biostudies-arrayexpress
Project description:Cancer cells adopt multiple strategies to avoid detection and destruction by the immune system, including exploiting immune checkpoint pathways. B7x (B7-H4, B7S1, or VTCN1), a member of the B7/CD28 family, is frequently expressed in advanced bladder cancer (BC), yet its role in BC progression and resistance to therapy remains poorly understood. Resistance to PD-1/PD-L1 immune checkpoint blockade immunotherapy significantly limits durable responses, with only 20%–25% of patients with muscle-invasive BC achieving long-term benefits. Here, we demonstrated that B7x mRNA and protein expression were associated with poor survival outcomes in muscle-invasive BC patients and mouse models of BC. Stable expression of B7x in immune-competent BC mouse models resulted in enhanced tumor growth and splenomegaly, driven by the exclusion and suppression of tumor-infiltrating anti-tumor immune cells and the enrichment of pro-tumor and immunosuppressive cells. Consistently, in the IMvigor210 clinical trial, high B7x mRNA expression was correlated with poorer survival in muscle-invasive BC patients treated with PD-L1 blockade. Notably, combination therapy targeting B7x alongside PD-1/PD-L1 or CTLA-4 blockade reduced tumor burden and overcame resistance to monotherapy. These findings establish B7x as a substantial driver of immune evasion in BC and highlight its potential as a therapeutic target to improve immune checkpoint blockade efficacy in muscle-invasive BC.
2025-12-30 | GSE315244 | GEO
Project description:Primary outcome(s): Correlation between PD-L1 expression in immune cells and soluble PD-L1 value. Correlation between PD-L1 expression in immune cells or soluble PD-L1 value and PD-L1 expression in tumor tissue. Characterstics of PD-L1 expression in immune cells or soluble PD-L1 value in each gastrointestinal cancer type.
| 2638777 | ecrin-mdr-crc
Project description:The PD-1/PD-L1 pathway maintains an immunosuppressive environment essential for neonatal heart regeneration
| PRJNA854636 | ENA