PD-1/PD-L1 immune checkpoint inhibitors in glioblastoma: clinical studies, challenges and potential.
Ontology highlight
ABSTRACT:
SUBMITTER: Yang T
PROVIDER: S-EPMC7899692 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:PD-1/PD-L1 checkpoint blockades have achieved significant progress in several kinds of tumours. Pembrolizumab, which targets PD-1, has been approved as a first-line treatment for advanced non-small cell lung cancer (NSCLC) patients with positive PD-L1 expression. However, PD-1/PD-L1 checkpoint blockades have not achieved breakthroughs in treating glioblastoma because glioblastoma has a low immunogenic response and an immunosuppressive microenvironment caused by the precise crosstalk between cytokines and immune cells. A phase III clinical trial, Checkmate 143, reported that nivolumab, which targets PD-1, did not demonstrate survival benefits compared with bavacizumab in recurrent glioblastoma patients. Thus, the combination of a PD-1/PD-L1 checkpoint blockade with RT, TMZ, antibodies targeting other inhibitory or stimulatory molecules, targeted therapy, and vaccines may be an appealing solution aimed at achieving optimal clinical benefit. There are many ongoing clinical trials exploring the efficacy of various approaches based on PD-1/PD-L1 checkpoint blockades in primary or recurrent glioblastoma patients. Many challenges need to be overcome, including the identification of discrepancies between different genomic subtypes in their response to PD-1/PD-L1 checkpoint blockades, the selection of PD-1/PD-L1 checkpoint blockades for primary versus recurrent glioblastoma, and the identification of the optimal combination and sequence of combination therapy. In this review, we describe the immunosuppressive molecular characteristics of the tumour microenvironment (TME), candidate biomarkers of PD-1/PD-L1 checkpoint blockades, ongoing clinical trials and challenges of PD-1/PD-L1 checkpoint blockades in glioblastoma.
| S-EPMC6380009 | biostudies-literature
Project description:Blockade of the immunoinhibitory PD-1/PD-L1 pathway using monoclonal antibodies has shown impressive results with durable clinical antitumor responses. Anti-PD-1 and anti-PD-L1 antibodies have now been approved for the treatment of a number of tumor types, whereas the development of small molecules targeting immune checkpoints lags far behind. We characterized two classes of macrocyclic-peptide inhibitors directed at the PD-1/PD-L1 pathway. We show that these macrocyclic compounds act by directly binding to PD-L1 and that they are capable of antagonizing PD-L1 signaling and, similarly to antibodies, can restore the function of T-cells. We also provide the crystal structures of two of these small-molecule inhibitors bound to PD-L1. The structures provide a rationale for the checkpoint inhibition by these small molecules, and a description of their small molecule/PD-L1 interfaces provides a blueprint for the design of small-molecule inhibitors of the PD-1/PD-L1 pathway.
| S-EPMC6400216 | biostudies-literature
Project description:Blocking the interaction between the programmed cell death (PD)-1 protein and one of its ligands, PD-L1, has been reported to have impressive antitumor responses. Therapeutics targeting this pathway are currently in clinical trials. Pembrolizumab and nivolumab are the first of this anti-PD-1 pathway family of checkpoint inhibitors to gain accelerated approval from the US Food and Drug Administration (FDA) for the treatment of ipilimumab-refractory melanoma. Nivolumab has been associated with improved overall survival compared with dacarbazine in patients with previously untreated wild-type serine/threonine-protein kinase B-raf proto-oncogene BRAF melanoma. Although the most mature data are in the treatment of melanoma, the FDA has granted approval of nivolumab for squamous cell lung cancer and the breakthrough therapy designation to immune- checkpoint inhibitors for use in other cancers: nivolumab, an anti-PD-1 monoclonal antibody, for Hodgkin lymphoma, and MPDL-3280A, an anti-PD-L1 monoclonal antibody, for bladder cancer and non-small cell lung cancer. Here we review the literature on PD-1 and PD-L1 blockade and focus on the reported clinical studies that have included patients with melanoma.PubMed was searched to identify relevant clinical studies of PD-1/PD-L1-targeted therapies in melanoma. A review of data from the current trials on clinicaltrial.gov was incorporated, as well as data presented in abstracts at the 2014 annual meeting of the American Society of Clinical Oncology, given the limited number of published clinical trials on this topic.The anti-PD-1 and anti-PD-L1 agents have been reported to have impressive antitumor effects in several malignancies, including melanoma. The greatest clinical activity in unselected patients has been seen in melanoma. Tumor expression of PD-L1 is a suggestive, but inadequate, biomarker predictive of response to immune-checkpoint blockade. However, tumors expressing little or no PD-L1 are less likely to respond to PD-1 pathway blockade. Combination checkpoint blockade with PD-1 plus cytotoxic T-lymphocyte antigen (CTLA)-4 blockade appears to improve response rates in patients who are less likely to respond to single-checkpoint blockade. Toxicity with PD-1 blocking agents is less than the toxicity with previous immunotherapies (eg, interleukin 2, CTLA-4 blockade). Certain adverse events can be severe and potentially life threatening, but most can be prevented or reversed with close monitoring and appropriate management.This family of immune-checkpoint inhibitors benefits not only patients with metastatic melanoma but also those with historically less responsive tumor types. Although a subset of patients responds to single-agent blockade, the initial trial of checkpoint-inhibitor combinations has reported a potential to improve response rates. Combination therapies appear to be a means of increasing response rates, albeit with increased immune-related adverse events. As these treatments become available to patients, education regarding the recognition and management of immune-related effects of immune-checkpoint blockade will be essential for maximizing clinical benefit.
| S-EPMC4497957 | biostudies-literature
Project description:Therapeutics targeting programmed death ligand 1 (PD-L1) protein and its receptor PD-1 are now dominant players in restoring anti-tumor immune responses. PD-L1 detection by immunohistochemistry (IHC) is emerging as a reproducible biomarker for guiding patient stratification for those therapies in some cancers. However, PD-L1 expression in the tumor microenvironment is highly complex. It is upregulated by aberrant genetic alterations, and is highly regulated at the transcriptional, posttranscriptional, and protein levels. Thus, PD-L1 IHC is inadequate to fully understand the relevance of PD-L1 levels in the whole body and their dynamics to improve therapeutic outcomes. Imaging technologies could potentially assist in meeting that need. Early clinical investigations show promising results in quantifying PD-L1 expression in the whole body by positron emission tomography (PET). Within this context, this review summarizes advancements in regulation of PD-L1 expression and imaging agents, and in PD-L1 PET for drug development, and discusses opportunities and challenges presented by these innovations for guiding immune checkpoint therapy (ICT).
| S-EPMC7692040 | biostudies-literature
Project description:Gastrointestinal (GI) malignant neoplasms have a high global incidence and treatment prospects for patients with advanced GI tumors are dismal. PD-1/PD-L1 inhibitors emerged as a frontline treatment for several types of cancer. However, the shortcomings of PD-1/PD-L1 inhibitors have been observed, including low objective response rates and acquired tumor resistance, especially in patients receiving PD-1/PD-L1 inhibitors as a single treatment. Accumulating evidence from clinical trials increasingly suggests that combined immunotherapies enhance therapeutic responses in patients with malignances, especially for GI tumors which have a complex matrix, and significant molecular and immunological differences. Preclinical and clinical studies suggest there are advantages to combined immunological regimens, which represents the next logical step in this field, although further research is necessary. This literature review explores the current limitations of monotherapies, before critically discussing the rationale behind combination regimens. Then, we provide a summary of the clinical applications for gastrointestinal cancers.
| S-EPMC6480748 | biostudies-literature
Project description:BackgroundIn recent years, PD-1/PD-L1 immune checkpoint inhibitors have improved cancer therapy in many tumor types, but no benefit of immune checkpoint therapy has been found in glioblastoma multiforme (GBM). Based on the results of our earlier work, which showed a reduction of PD-L1 expression in patients treated with temozolomide (TMZ), we aimed to investigate the link between TMZ therapy and the immune control point target PD-L1.MethodsRNA-sequencing data from de-novo and recurrent glioblastoma were analyzed by AutoPipe algorithm. Results were confirmed either in a cell model by two primary and one established GBM cell line and specimens of de-novo and recurrent GBM. PD-L1 and pathway activation of the JAK/STAT pathway was analyzed by quantitative real-time PCR and western blot.ResultsWe found a significant downregulation of the JAK/STAT pathway and immune response in recurrent tumors. The cell model showed an upregulation of PD-L1 after IFNγ treatment, while additional TMZ treatment lead to a reduction of PD-L1 expression and JAK/STAT pathway activation. These findings were confirmed in specimens of de-novo and recurrent glioblastoma.ConclusionsOur results suggest that TMZ therapy leads to a down-regulation of PD-L1 in primary GBM cells. These results support the clinical findings where PD-L1 is significantly reduced in recurrent GBMs. If the target is diminished, it may also lead to impaired efficacy of PD-1/PD-L1 inhibitors such as nivolumab.
| S-EPMC6359796 | biostudies-literature
Project description:Blockade of the programmed cell death-1/programmed cell death ligand-1 (PD-1/PD-L1) immune checkpoint pathway is an efficient immunotherapeutic modality that provided significant advances in cancer treatment especially in solid tumors highly resistant to traditional therapy. Monoclonal antibodies (mAbs) and small-molecule inhibitors are the two main strategies used to block this axis with mAbs suffering from many limitations. Accordingly, the current alternative is the development of small-molecule PD-1/PD-L1 inhibitors. Here, we present a sequential virtual screening (VS) protocol involving pharmacophore screening followed by molecular docking for the discovery of novel PD-L1 inhibitors. The VS protocol resulted in the discovery of eight novel compounds. A 100 ns MD simulation showed two compounds, H4 and H6, exhibiting a stable binding mode at the PD-L1 dimer interface. Upon evaluation of their immunological activities, the two compounds induced higher cytokines levels (IL-2, IL-6, and INF-γ) relative to BMS-202, 72 h post treatment of PBMCs of HCC patients. Thus, the discovered hits represent potential leads for the development of novel classes targeting the PD-L1 receptor as anti-hepatocellular carcinoma agents.
| S-EPMC10515376 | biostudies-literature
Project description:Antibodies targeting the PD-1/PD-L1 immune checkpoint achieved spectacular success in anticancer therapy in the recent years. In contrast, no small molecules with cellular activity have been reported so far. Here we provide evidence that small molecules are capable of alleviating the PD-1/PD-L1 immune checkpoint-mediated exhaustion of Jurkat T-lymphocytes. The two optimized small-molecule inhibitors of the PD-1/PD-L1 interaction, BMS-1001 and BMS-1166, developed by Bristol-Myers Squibb, bind to human PD-L1 and block its interaction with PD-1, when tested on isolated proteins. The compounds present low toxicity towards tested cell lines and block the interaction of soluble PD-L1 with the cell surface-expressed PD-1. As a result, BMS-1001 and BMS-1166 alleviate the inhibitory effect of the soluble PD-L1 on the T-cell receptor-mediated activation of T-lymphocytes. Moreover, the compounds were effective in attenuating the inhibitory effect of the cell surface-associated PD-L1. We also determined the X-ray structures of the complexes of BMS-1001 and BMS-1166 with PD-L1, which revealed features that may be responsible for increased potency of the compounds compared to their predecessors. Further development may lead to the design of an anticancer therapy based on the orally delivered immune checkpoint inhibition.
| S-EPMC5641120 | biostudies-literature
Project description:Computational approaches in immune-oncology therapies focus on using data-driven methods to identify potential immune targets and develop novel drug candidates. In particular, the search for PD-1/PD-L1 immune checkpoint inhibitors (ICIs) has enlivened the field, leveraging the use of cheminformatics and bioinformatics tools to analyze large datasets of molecules, gene expression and protein-protein interactions. Up to now, there is still an unmet clinical need for improved ICIs and reliable predictive biomarkers. In this review, we highlight the computational methodologies applied to discovering and developing PD-1/PD-L1 ICIs for improved cancer immunotherapies with a greater focus in the last five years. The use of computer-aided drug design structure- and ligand-based virtual screening processes, molecular docking, homology modeling and molecular dynamics simulations methodologies essential for successful drug discovery campaigns focusing on antibodies, peptides or small-molecule ICIs are addressed. A list of recent databases and web tools used in the context of cancer and immunotherapy has been compilated and made available, namely regarding a general scope, cancer and immunology. In summary, computational approaches have become valuable tools for discovering and developing ICIs. Despite significant progress, there is still a need for improved ICIs and biomarkers, and recent databases and web tools have been compiled to aid in this pursuit.
| S-EPMC10054797 | biostudies-literature
Project description:Immune checkpoint blockade is one of the most promising strategies of cancer immunotherapy. However, unlike classical targeted therapies, it is currently solely based on expensive monoclonal antibodies, which often inflict immune-related adverse events. Herein, we propose a novel small-molecule inhibitor targeted at the most clinically relevant immune checkpoint, PD-1/PD-L1. The compound is capable of disrupting the PD-1/PD-L1 complex by antagonizing PD-L1 and, therefore, restores activation of T cells similarly to the antibodies, while being cheap in production and possibly nonimmunogenic. The final compound is significantly smaller than others reported in the literature while being nontoxic to cells even at high concentrations. The scaffold was designed using a structure-activity relationship screening cascade based on a new antagonist-induced dissociation NMR assay, called the weak-AIDA-NMR. Weak-AIDA-NMR finds true inhibitors, as opposed to only binders to the target protein, in early steps of lead compound development, and this process makes it less time and cost consuming.
| S-EPMC7584369 | biostudies-literature