Pyroptosis, driven by the N-terminal domain of gasdermin proteins (GSDM), promotes antitumor immunity by attracting lymphocytes to the tumor microenvironment (TME). However, current pyroptosis-inducing therapies like drug injections and phototherapy are limited to localized treatments, making them unsuitable for widespread or microscopic metastatic lesions. This study engineered oncolytic M1 viruses (rM1-mGSDME_FL and rM1-mGSDME_NT) to selectively deliver GSDME to tumor cells.
View Article and Find Full Text PDFOncolytic viruses (OVs), a group of replication-competent viruses that can selectively infect and kill cancer cells while leaving healthy cells intact, are emerging as promising living anticancer agents. Unlike traditional drugs composed of non-replicating compounds or biomolecules, the replicative nature of viruses confer unique pharmacokinetic properties that require further studies. Despite some pharmacokinetics studies of OVs, mechanistic insights into the connection between OV pharmacokinetics and antitumor efficacy remain vague.
View Article and Find Full Text PDFThe immune response plays a crucial role in the functionality of oncolytic viruses. In this study, Albendazole, an antihelminthic drug known to modulate the immune checkpoint PD-L1, was combined with the oncolytic virus M1 (OVM1) to treat mice with either prostate cancer (RM-1) or glioma (GL261) tumors. This combination therapy enhanced anti-tumor effects in immunocompetent mice, but not in immunodeficient ones, without increasing OVM1 replication.
View Article and Find Full Text PDFOncolytic viruses are emerging as promising anticancer agents. Although the essential biological function of N-glycosylation on viruses are widely accepted, roles of N-glycan and glycan-processing enzyme in oncolytic viral therapy are remain elusive. Here, via cryo-EM analysis, we identified three distinct N-glycans on the envelope of oncolytic virus M1 (OVM) as being necessary for efficient receptor binding.
View Article and Find Full Text PDFAlthough promising, dendritic cell (DC) vaccines still provide limited clinical benefits, mainly due to the immunosuppressive tumor microenvironment (TME) and the lack of tumor-associated antigens (TAAs). Oncolytic virus therapy is an ideal strategy to overcome immunosuppression and expose TAAs; therefore, they may work synergistically with DC vaccines. In this study, we demonstrate that oncolytic virus M1 (OVM) can enhance the antitumor effects of DC vaccines across diverse syngeneic mouse tumor models by increasing the infiltration of CD8 effector T cells in the TME.
View Article and Find Full Text PDFGlioblastoma (GBM) is the deadliest form of brain cancer. It is a highly angiogenic and immunosuppressive malignancy. Although immune checkpoint blockade therapies have revolutionized treatment for many types of cancer, their therapeutic efficacy in GBM has been far less than expected or even ineffective.
View Article and Find Full Text PDFOncolytic viruses (OVs) represent a type of encouraging multi-mechanistic drug for the treatment of cancer. However, attenuation of virulence, which is generally required for the development of OVs based on pathogenic viral backbones, is frequently accompanied by a compromised killing effect on tumor cells. By exploiting the property of viruses to evolve and adapt in cancer cells, we perform directed natural evolution on refractory colorectal cancer cell HCT-116 and generate a next-generation oncolytic virus M1 (NGOVM) with an increase in the oncolytic effect of up to 9690-fold.
View Article and Find Full Text PDFDifferentiation therapy using small molecules is a promising strategy for improving the prognosis of glioblastoma (GBM). Histone acetylation plays an important role in cell fate determination. Nevertheless, whether histone acetylation in specific sites determines GBM cells fate remains to be explored.
View Article and Find Full Text PDFJ Neuroinflammation
December 2022
Background: Dysregulated activation of the inflammasome is involved in various human diseases including acute cerebral ischemia, multiple sclerosis and sepsis. Though many inflammasome inhibitors targeting NOD-like receptor protein 3 (NLRP3) have been designed and developed, none of the inhibitors are clinically available. Growing evidence suggests that targeting apoptosis-associated speck-like protein containing a CARD (ASC), the oligomerization of which is the key event for the assembly of inflammasome, may be another promising therapeutic strategy.
View Article and Find Full Text PDFAs one of the key injury incidents, tissue acidosis in the brain occurs very quickly within several minutes upon the onset of ischemic stroke. Glutamate, an excitatory amino acid inducing neuronal excitotoxicity, has been reported to trigger the decrease in neuronal intracellular pH (pHi) via modulating proton-related membrane transporters. However, there remains a lack of clarity on the possible role of glutamate in neuronal acidosis via regulating metabolism.
View Article and Find Full Text PDFAccumulating evidence supports the existence of glioma stem cells (GSCs) and their critical role in the resistance to conventional treatments for glioblastoma multiforme (GBM). Differentiation therapy represents a promising alternative strategy against GBM by forcing GSCs to exit the cell cycle and reach terminal differentiation. In this study, we demonstrated that cAMP triggered neuronal differentiation and compromised the self-renewal capacity in GSCs.
View Article and Find Full Text PDFOncolytic viruses (OVs) have become a category of promising anticancer immunotherapeutic agents over the last decade. However, the fact that many individuals fail to respond to OVs highlights the importance of defining the barely known immunosuppressive mechanisms that lead to treatment resistance. Here we found that the immunosuppression mediated by tumor-associated myeloid cells (TAMCs) directly quenches the antitumor effect of oncolytic virus M1 (OVM).
View Article and Find Full Text PDFOver the last decade, oncolytic virus (OV) therapy has shown its promising potential in tumor treatment. The fact that not every patient can benefit from it highlights the importance for defining biomarkers that help predict patients' responses. As particular self-amplifying biotherapeutics, the anti-tumor effects of OVs are highly dependent on the host factors for viral infection and replication.
View Article and Find Full Text PDFThe prognosis of malignant gliomas remains poor, with median survival fewer than 20 months and a 5-year survival rate merely 5%. Their primary location in the central nervous system (CNS) and its immunosuppressive environment with little T cell infiltration has rendered cancer therapies mostly ineffective, and breakthrough therapies such as immune checkpoint inhibitors (ICIs) have shown limited benefit. However, tumor immunotherapy is developing rapidly and can help overcome these obstacles.
View Article and Find Full Text PDFTriple-negative breast cancer (TNBC) is the most aggressive molecular subtype among breast tumors and remains a challenge even for the most current therapeutic regimes. Here, we demonstrate that oncolytic alphavirus M1 effectively kills both TNBC and non-TNBC. ER-stress and apoptosis pathways are responsible for the cell death in non-TNBC as reported in other cancer types, yet the cell death in TNBC does not depend on these pathways.
View Article and Find Full Text PDFOncolytic virotherapies are perceived as remarkable immunotherapies coming into view and represent highly promising cancer treatments, yet to figure out its specific immune responses and underlying barriers remains critical. Albeit recent studies have demonstrated that oncolytic viruses (OVs) could fine tune tumor microenvironment (TME) to elicit tumor suppression mainly due to effective T-cell responses, the interaction between suppressive T cells and OVs is barely undetermined. Herein, we found that regulatory T cells (Treg cells) were increased in the TME following systemic administration of oncolytic virus M1 along with the higher expression of relative cytokines and chemokines in both mouse RM-1 prostatic carcinoma model and mouse B16F10 melanoma model.
View Article and Find Full Text PDFFollowing the publication of our paper (Zhang et al., 2020), it has come to our attention that we erroneously listed two funding sources unrelated to this study in the "ACKNOWLEDGEMENTS" section. Hereby, we wish to update the "ACKNOWLEDGEMENTS" section as a correction.
View Article and Find Full Text PDFActivation of the cyclic adenosine monophosphate (cAMP) pathway induces the glial differentiation of glioblastoma (GBM) cells, but the fate of differentiated cells remains poorly understood. Transcriptome analyses have revealed significant changes in the cell cycle- and senescence-related pathways in differentiated GBM cells induced by dibutyryl cAMP (dbcAMP). Further investigations showed that reactive oxygen species (ROS) derived from enhanced mitochondrial function are involved in senescence induction and proliferation inhibition.
View Article and Find Full Text PDFAlphavirus M1 is a promising oncolytic virus for cancer therapy. Here, we constructed a fluorescent reporter virus for real-time visualization and quantification of M1 virus both and . The reporter-encoding M1 virus maintained the characteristics of parental virus in the aspects of structure, replication capacity, the feature to induce cytopathic cell death, and the property of tumor targeting.
View Article and Find Full Text PDFOncolytic alphavirus M1 has been shown to selectively target and kill cancer cells, but cytopathic morphologies induced by M1 virus and the life cycle of the M1 strain in cancer cells remain unclear. Here, we study the key stages of M1 virus infection and replication in the M1 virus-sensitive HepG2 liver cancer cell line by transmission electron microscopy, specifically examining viral entry, assembly, maturation and release. We found that M1 virus induces vacuolization of cancer cells during infection and ultimately nuclear marginalization, a typical indicator of apoptosis.
View Article and Find Full Text PDFNanoKnife, a nonthermal ablation technique also termed irreversible electroporation (IRE), has been adopted in locally advanced pancreatic cancer (LAPC) treatment. However, reversible electroporation (RE) caused by heterogeneous electric field magnitude leads to inadequate ablation and tumor recurrence. Alphavirus M1 has been identified as a novel natural oncolytic virus which is nonpathogenic and with high tumor selectivity.
View Article and Find Full Text PDFOncolytic virus is an effective therapeutic strategy for cancer treatment, which exploits natural or manipulated viruses to selectively target and kill cancer cells. However, the innate antiviral system of cancer cells may resistant to the treatment of oncolytic virus. M1 virus is a newly identified oncolytic virus belonging to alphavirus species, but the molecular mechanisms underlying its anticancer activity are largely unknown.
View Article and Find Full Text PDFReversing the highly immunosuppressive tumor microenvironment (TME) is essential to achieve long-term efficacy with cancer immunotherapy. Despite the impressive clinical response to checkpoint blockade in multiple types of cancer, only a minority of patients benefit from this approach. Here, we report that the oncolytic virus M1 induces immunogenic tumor cell death and subsequently restores the ability of dendritic cells to prime antitumor T cells.
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