Junwen Zhang

Oncolytic virus therapy is a highly promising approach for the treatment of glioblastoma (GBM). The RNA alteration N6-methyladenosine (m⁶A) is essential in GBM progression; however its specific function in oncolytic virotherapy remains unclear. We employed a new oncolytic herpes simplex virus type 1 (HSV-1), designated oHSV-1, which we had previously engineered. Mechanistic studies were performed to elucidate the involved pathways. We demonstrate that oHSV-1 specifically downregulates the m⁶A demethylase ALKBH5, leading to GBM cell death. Mechanistically, ALKBH5 downregulation elevates m⁶A modification on the transcript of the arginine methyltransferase CARM1, which promotes mRNA degradation and reduces protein expression. As CARM1 is a vital regulator of apoptosis, its loss triggers tumor cell apoptosis. Thus, our study identifies the ALKBH5-m⁶A-CARM1 axis as a critical mechanism underlying oHSV-1-induced apoptosis in GBM cells. Moreover, the combination of oHSV-1 and CARM1 inhibitor shows a markedly enhanced effect on suppressing tumor cell proliferation in vitro. These findings reveal a novel epigenetic mechanism of oHSV-1-induced apoptosis and support the therapeutic potential of combining oHSV-1 with epigenetic inhibitors for GBM treatment.

Lipid metabolic reprogramming has emerged as a hallmark in cancer research, especially that of fatty acids (FAs). It promotes the effective utilization of the limited nutrients in the tumor microenvironment (TME) by the cells and has considerably been associated with immune escape. Tumor cells exhibit enhanced FA uptake, synthesis, and oxidation for metabolic adaptation, and non-tumor cells also undergo FA metabolic remolding in the TME. Owing to the essential role of FA metabolism in TME, the associated critical enzymes may be targeted for developing novel therapeutic approaches. This review aims to comprehensively summarize the FA metabolic landscapes in various cancers and FA-related molecular changes, FA metabolic reprogramming in different cells in the TME to identify potential targets, and FA-related cell interactions and underlying mechanisms in the TME. The findings of this study may provide insights into exploring the intricate FA metabolism–TME adaptation interplay to uncover potential metabolic targets of therapeutic significance for combinatorial strategies and enhancing immunotherapy.

Background: Chimeric antigen receptor (CAR) T-cell therapy has shown limited efficacy in glioblastoma (GBM) due to tumor antigen heterogeneity and the immunosuppressive microenvironment. To address these barriers, we developed a novel combinatorial approach: engineering CAR-T cells with third-generation oncolytic adenoviruses (OAd) to enable targeted viral delivery and sustained immune activation. Unlike conventional OAd administration, this strategy leverages CAR-T cells as tumor-tropic vectors for localized oncolysis and cytokine modulation. Methods: CD70-specific CAR-T cells were transduced with two third-generation OAds (E1B19K/E3-deleted, replication-selective): OAd-GFP (control) or OAd-IL15 (TS-2021), generating CAR-T^OAd−GFP and CAR-T^TS−2021. Viral replication kinetics and CAR-T expansion were assessed in vitro. OAd delivery efficiency was quantified by co-culturing CAR-T^OAd cells with GBM cells. Flow cytometry was used to analyze IL15-mediated effects on stem-like markers (CCR7, CD45RA) and exhaustion markers (PD-1, TIM-3, and LAG-3) after repeated antigen stimulation. Antitumor activity was evaluated in vitro using cytotoxicity assays and in NCG mice bearing orthotopic GBM xenografts. Mechanistic studies were conducted using RNA-seq and Western blotting. Results: In this study, we found that genetically engineered OAd-GFP can specifically replicate within CAR-T cells and be precisely delivered to GBM through an antigen-specific mechanism. Prolonged antigen stimulation induced T-cell exhaustion, limiting the efficacy of CAR-T therapy. TS-2021-infected CAR-T cells exhibited enhanced expansion and persistence in vitro, with reduced expression of exhaustion markers under sustained antigen stimulation. IL15 autocrine signaling activated JAK-STAT and MAPK-ERK pathways. This process repaired the DNA damage induced by OAd in CAR-T cells and maintained their expansion and persistence. By combining OAd-mediated oncolysis with IL15-driven CAR-T persistence, CAR-T^TS−2021 cells demonstrated potent antitumor efficacy against GBM both in vitro and in vivo. Conclusions: By integrating IL15-armed OAd into CAR-T cells, we demonstrate a synergistic strategy that simultaneously enhances viral oncolysis, sustains T-cell persistence, and counteracts GBM immunosuppression. This approach addresses both antigenic heterogeneity and microenvironment-driven resistance, providing a translatable paradigm for solid tumor immunotherapy.

Aims: Patients with glioblastoma multiforme (GBM) do not benefit from current cancer treatments, and their prognosis is dismal. This study aimed to investigate the potential synergistic effects of TS‐2021, a third‐generation oncolytic adenovirus, combined with the PARP inhibitor olaparib in GBM.Methods: TS‐2021’s impact on p66shc‐induced apoptosis, DNA damage response, and poly (ADP‐ribose) polymerase (PARP) activation was evaluated in GBM cells. The synergistic effect of TS‐2021 and olaparib was examined in GBM cell lines and an immunocompetent mouse model of GBM. Mechanistic studies focused on the role of p66shc phosphorylation in the observed effects.Results: TS‐2021 triggered p66shc‐induced apoptosis, DNA damage response, and PARP activation. The combination of TS‐2021 and olaparib synergistically increased cell apoptosis and DNA damage and reduced PARP expression compared to monotherapy. Olaparib promoted TS‐2021 replication and release in GBM cells. Mechanistically, olaparib combined with TS‐2021 upregulated p66shc phosphorylation, enhancing tumor cell apoptosis. In vivo, the combination therapy inhibited tumor growth and prolonged survival, confirming the synergistic effect.Conclusion: This study is the first to suggest that TS‐2021 sensitizes GBM cells with wild‐type BRCA1/2 to olaparib. The combination of TS‐2021 and olaparib shows a synergistic therapeutic effect against GBM, providing a promising treatment strategy.

As one of the main components of the glioma immune microenvironment, glioma-associated macrophages (GAMs) have increasingly drawn research interest. Primarily comprised of resident microglias and peripherally derived mononuclear macrophages, GAMs are influential in a variety of activities such as tumor cell resistance to chemotherapy and radiotherapy as well as facilitation of glioma pathogenesis. In addition to in-depth research of GAM polarization, study of mechanisms relevant in tumor microenvironment recruitment has gradually increased. Suppression of GAMs at their source is likely to produce superior therapeutic outcomes. Here, we summarize the origin and recruitment mechanism of GAMs, as well as the therapeutic implications of GAM inhibition, to facilitate future glioma-related research and formulation of more effective treatment strategies.

Purpose Uveal melanoma (UM) is the most common primary intraocular malignant tumor in adults, with patients having a low overall survival rate. Oncolytic viruses (OVs) have been shown effective as monotherapy or combined with immunotherapy in the treatment of UM. Oncolytic herpes simplex type I virus (oHSV-1) was found to alter gene expression and immune function in UMs. We investigated whether a combination treatment would be more effective in treating UM and reactive immune cells. Methods RNA sequencing analysis were used to identify the effect of oHSV-1 infection in UM cells and protein changes were validated by western blot. Cell viability assays were performed through UM cell lines (MUM2B, 92.1, and MP41) and retinal pigment epithelial cell line (ARPE-19) to identify the efficacy and safety of the combination treatment. Western blot, qRT-PCR, cell viability assay and immunocytochemistry were performed to discover the reactivation of immune cells (U937 and HMC3). Results Through RNA sequencing analysis and in vitro molecular biology assays, this study tested the ability of oHSV-1 combined with the TLR3 agonist poly(I:C) to re-activate the TLR3 meditated NF-ƙB signaling pathway and further increase the anti-tumor activity of UM cells and macrophages, including the stimulation of macrophage polarization and proliferation. Conclusions These findings indicate that the treatment of UM with a combination of oHSV-1 and poly(I:C) generates immune responses and enhances anti-tumoral activity, suggesting the need for further investigations and clinical trials of this combination.

Glioblastoma multiforme (GBM) is a common intracranial malignancy characterized by abundant and aberrant vasculature. The efficiency of existing antivascular treatments remains unsatisfactory. The transition of glioblastoma stem-like cells (GSCs) into tumor endothelioid cells (ECs) has been thought to cause glioma neovascularization and anti-angiogenesis tolerance, but the mechanisms regulating glioma transdifferentiation remains unclear. Our previous study found that P4HA1 regulates GSCs vascular mimicry in a hypoxic microenvironment, but the detailed molecular mechanism has not been determined. In this study, candidate protein COL6A1 was screened by mass spectrometry. In vitro experiments show that P4HA1 regulates the expression of CD31 via COL6A1, with the levels of expression of P4HA1, COL6A1 and the vascular endothelial molecular markers CD31 showing positive correlations in vivo assay. Altering the expression of P4HA1 in GSCs altered the expression of COL6A1 and CD31, thereby inducing glioma angiogenesis. In conclusion, this study revealed that the P4HA1/COL6A1 axis modulates the transdifferentiation process of GSCs into ECs. Interrupting this signaling axis can inhibit glioma angiogenesis, suggesting that this axis may be a novel target for antivascular therapy in patients with glioma.

Background: Polarization of microglia cells in the glioma microenvironment is closely related to the malignant progression and invasion of gliomas. Prolyl 4-hydroxylase subunit α 1 (P4HA1) is the rate-limiting subunit of prolyl 4-hydroxylase (P4H). In previous studies, we showed that P4HA1 could promote the proliferation, migration, and invasion of glioma cells, but the specific mechanisms through which this occurs have not been fully elucidated. Materials and Methods: Interactions between glioma and microglia cells were analyzed using bioinformatics. Then, co-culture models were used to obtain conditioned media. To characterize microglial cell polarization, we used PCR and immunofluorescence. Proliferation and invasion assays were used to explore the biological behavior of glioma cells affected by microglia. Finally, marker expression was detected using immunohistochemistry in glioblastoma multiform (GBM) specimens. Results: Knockdown of P4HA1 resulted in reduced chemotaxis of microglia toward GBM cells and increased polarization of microglia toward the M1 phenotype. The changed microglial polarization state, in turn, inhibited the proliferation and invasion of GBM cells. Moreover, in GBM tissue specimens, the P4HA1 expression level is negatively correlated with that of the CD86 microglia M1-specific marker. Conclusion: Our results show that P4HA1 promotes immunosuppressive microenvironment formation by cross-talk between GBM and microglia cells and indirectly increases the aggressiveness of GBM.