Similar Datasets
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:Development of a PD-L1-expressing orthotopic liver cancer model
| PRJNA418077 | ENA
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: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:PD-L1 Inhibitor Regulates the miR-33a-5p/PTEN Signaling Pathway and Can Be Targeted to Sensitize Glioblastomas to Radiation. Glioblastoma (GBM) is the most common and lethal brain tumor in adults. Ionizing radiation (IR) is a standard treatment for GBM patients and results in DNA damage. However, the clinical efficacy of IR is limited due to therapeutic resistance. The programmed death ligand 1 (PD-L1) blockade has a shown the potential to increase the efficacy of radiotherapy by inhibiting DNA damage and repair responses. The miR-33a-5p is an essential microRNA that promotes GBM growth and self-renewal. In this study, we investigated whether a PD-L1 inhibitor (a small molecule inhibitor) exerted radio-sensitive effects to impart an anti-tumor function in GBM cells by modulating miR-33a-5p. U87 MG cells and U251 cells were pretreated with PD-L1 inhibitor. The PD-L1 inhibitor-induced radio-sensitivity in these cells was assessed by assaying cellular apoptosis, clonogenic survival assays, and migration. TargetScan and luciferase assay showed that miR-33a-5p targeted the phosphatase and tensin homolog (PTEN) 3' untranslated region. The expression level of PTEN was measured by western blotting, and was also silenced using small interfering RNAs. The levels of DNA damage following radiation was measured by the presence of γ-H2AX foci, cell cycle, and the mRNA of the DNA damage-related genes, BRCA1, NBS1, RAD50, and MRE11. Our results demonstrated that the PD-L1 inhibitor significantly decreased the expression of the target gene, miR-33a-5p. In addition, pretreatment of U87 MG and U251 cells with the PD-L1 inhibitor increased radio-sensitivity, as indicated by increased apoptosis, while decreased survival and migration of GBM cells. Mir-33a-5p overexpression or silencing PTEN in U87 MG and U251 cells significantly attenuated PD-L1 radiosensitive effect. Additionally, PD-L1 inhibitor treatment suppressed the expression of the DNA damage response-related genes, BRCA1, NBS1, RAD50, and MRE11. Our results demonstrated a novel role for the PD-L1 inhibitor in inducing radio- sensitivity in GBM cells, where inhibiting miR-33a-5p, leading to PTEN activated, and inducing DNA damage was crucial for antitumor immunotherapies to treat GBM.
2020-04-21 | E-MTAB-9007 | biostudies-arrayexpress
Project description:Although membrane-anchored Pd-l1 has been well-studied for its engagement with PD-1 on T cells to evade anti-tumor immunity, whether Pd-l1 regulate oncogenic signaling pathways in tumor cells remains elusive. In this experiment, to further dissect roles of the K262 residue acetylation for Pd-l1 nuclear function, we profiled RNA expression of WT or K262Q mutant mouse Pd-l1 re-expressed in CT26 KO Pd-l1 cells. Methods: Total RNA fromCT26/Vector, CT26/WT or CT26 Pd-l1 KO cells was purified using Qiagen RNeasy mini kit (Qiagen) according to the manufacturer’s instructions. Library preparation and sequenceing analysis were performed by BGI-Hong Kong Co. Ltd. Conclusions: Our study indicates that Pd-l1 acetylation modification may affect its function in nuclear.
2020-06-07 | GSE146557 | GEO
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.
2015-05-01 | GSE65041 | GEO
Project description:Although membrane-anchored PD-L1 has been well-studied for its engagement with PD-1 on T cells to evade anti-tumor immunity, whether PD-L1 regulate oncogenic signaling pathways in tumor cells remains elusive. We found that a portion of PD-L1 could translocate to the nucleus and knockout of PD-L1 changed RNA profiles in MDA-MB-231 cells. To further explore potential role of PD-L1 in regulating gene expression in tumor cells, we performed ChIP-seq in HA tag-inserted (after the signal peptide) PD-L1 re-expressed MBA-MB-231cells (endogenous PD-L1 knockout background). Methods: HA-insert-PD-L1 was re-introduced into MDA-MB-231 PD-L1 knockout cells using lentivirus and then the infected cells were selected with puromycin to make stable subclones. ChIP experiments were performed using HA antibody (Abcam, ab9110). Conclusions: Our study indicates that nuclear PD-L1 has potential roles in regulating gene transcription. More efforts are needed to further dissect the exact working model.
2020-06-07 | GSE146648 | GEO
Project description:PD-L1 acts as an immune checkpoint that inhibits T cell activation and suppresses colonic inflammation. We aimed at determine the cellular and molecular mechanisms underlying PD-L1 function in colon epithelium and colon cancer. scRNA-seq was perform to determine the gene expression profiles in epithelial cells and immune cells in the single-cell level. Tumors were induced in WT and PD-L1 KO mice. Analysis of WT and PD-L1 KO tumors revealed that loss of PD-L1 alters T cells, myeloid cells, B cells, and tumor-associated fibroblast subpopulations. Our finding determines that PD-L1 regulates multiple cellular populations to regulates host immune response and tumor development.
2024-10-01 | GSE246038 | GEO
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