Vasorin promotes endothelial differentiation of glioma stem cells via stimulating the transcription of VEGFR2.

Gliomas are highly vascularized malignancies, but current anti-angiogenic treatments have not demonstrated practical improvements in patient survival. Studies have suggested that glioma-derived endothelial cell (GdEC) formed by glioma stem cell (GSC) differentiation may contribute to the failure of this treatment. However, the molecular mechanisms involved in GSC endothelial differentiation remain poorly understood. We previously reported that vasorin (VASN) is highly expressed in glioma and promotes angiogenesis. Here, we show that VASN expression positively correlates with GdEC signatures in glioma patients. VASN promotes the endothelial differentiation capacity of GSC in vitro and participates in the formation of GSC-derived vessels in vivo. Mechanistically, vascular endothelial growth factor receptor 2 (VEGFR2) is a critical factor that mediates the regulation of VASN on GSC endothelial differentiation. Separation of cell chromatin fractionation and chromatin immunoprecipitation-sequencing analysis show that VASN interacts with Notch1 and co-translocates into the cell nuclei, where VASN binds to the VEGFR2 gene promoter to stimulate its transcription during the progression of GSC differentiation into GdEC. Together, these findings elucidate the role and mechanisms of VASN in promoting the endothelial differentiation of GSC and suggest VASN as a potential target for anti-angiogenic therapy based on intervention in GdEC formation in gliomas.

Nuclear VCP drives colorectal cancer progression by promoting fatty acid oxidation.

Fatty acid oxidation (FAO) fuels many cancers. However, knowledge of pathways that drive FAO in cancer remains unclear. Here, we revealed that valosin-containing protein (VCP) upregulates FAO to promote colorectal cancer growth. Mechanistically, nuclear VCP binds to histone deacetylase 1 (HDAC1) and facilitates its degradation, thus promoting the transcription of FAO genes, including the rate-limiting enzyme carnitine palmitoyltransferase 1A (CPT1A). FAO is an alternative fuel for cancer cells in environments exhibiting limited glucose availability. We observed that a VCP inhibitor blocked the upregulation of FAO activity and CPT1A expression triggered by metformin in colorectal cancer (CRC) cells. Combined VCP inhibitor and metformin prove more effective than either agent alone in culture and in vivo. Our study illustrates the molecular mechanism underlying the regulation of FAO by nuclear VCP and demonstrates the potential therapeutic utility of VCP inhibitor and metformin combination treatment for colorectal cancer.

Targeting VCP potentiates immune checkpoint therapy for colorectal cancer.

Immune checkpoint blockade therapies are still ineffective for most patients with colorectal cancer (CRC). Immunogenic cell death (ICD) enables the release of key immunostimulatory signals to drive efficient anti-tumor immunity, which could be used to potentiate the effects of immune checkpoint inhibitors. Here, we showed that inhibition of valosin-containing protein (VCP) elicits ICD in CRC. Meanwhile, VCP inhibitor upregulates PD-L1 expression and compromises anti-tumor immunity in vivo. Mechanistically, VCP transcriptionally regulates PD-L1 expression in a JAK1-dependent manner. Combining VCP inhibitor with anti-PD1 remodels tumor immune microenvironment and reduces tumor growth in mouse models of CRC. Addition of oncolytic virus further augments the therapeutic activity of the combination regimen. Our study shows the molecular mechanism for regulating PD-L1 expression by VCP and suggests that inhibition of VCP has the potential to increase the efficacy of immunotherapy in CRC.

IDH1 mutation impairs antiviral response and potentiates oncolytic virotherapy in glioma.

IDH1 mutations frequently occur early in human glioma. While IDH1 mutation has been shown to promote gliomagenesis via DNA and histone methylation, little is known regarding its regulation in antiviral immunity. Here, we discover that IDH1 mutation inhibits virus-induced interferon (IFN) antiviral responses in glioma cells. Mechanistically, D2HG produced by mutant IDH1 enhances the binding of DNMT1 to IRF3/7 promoters such that IRF3/7 are downregulated, leading to impaired type I IFN response in glioma cells, which enhances the susceptibility of gliomas to viral infection. Furthermore, we identify DNMT1 as a potential biomarker predicting which IDH1mut gliomas are most likely to respond to oncolytic virus. Finally, both D2HG and ectopic mutant IDH1 can potentiate the replication and oncolytic efficacy of VSVΔ51 in female mouse models. These findings reveal a pivotal role for IDH1 mutation in regulating antiviral response and demonstrate that IDH1 mutation confers sensitivity to oncolytic virotherapy.

Glioblastoma Vascular Plasticity Limits Effector T-cell Infiltration and Is Blocked by cAMP Activation.

Glioblastoma (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. In this study, we found that the genomic signature of glioma-derived endothelial cells (GdEC) correlates with an immunosuppressive state and poor prognosis of patients with glioma. We established an in vitro model of GdEC differentiation for drug screening and used this to determine that cyclic adenosine monophosphate (cAMP) activators could effectively block GdEC formation by inducing oxidative stress. Furthermore, cAMP activators impaired GdEC differentiation in vivo, normalized the tumor vessels, and altered the tumor immune profile, especially increasing the influx and function of CD8+ effector T cells. Dual blockade of GdECs and PD-1 induced tumor regression and established antitumor immune memory. Thus, our study reveals that endothelial transdifferentiation of GBM shapes an endothelial immune cell barrier and supports the clinical development of combining GdEC blockade and immunotherapy for GBM. See related Spotlight by Lee et al., p. 1300.

SOX2 regulates paclitaxel resistance of A549 non­small cell lung cancer cells via promoting transcription of ClC­3.

Paclitaxel (PTX) is widely used in the treatment of non­small cell lung cancer (NSCLC). However, acquired PTX drug resistance is a major obstacle to its therapeutic efficacy and the underlying mechanisms are still unclear. The present study revealed a novel role of the SRY­box transcription factor 2 (SOX2)­chloride voltage­gated channel­3 (ClC­3) axis in PTX resistance of A549 NSCLC cells. The expression levels of SOX2 and ClC­3 were upregulated in PTX­resistant A549 NSCLC cells by RT­qPCR and western blotting. The drug resistance to PTX of A549 NSCLC cells were measured by detecting the cell viability and the expression of drug resistance markers. Knockdown of SOX2 or ClC­3 effectively decreased PTX resistance of A549 NSCLC cells, whereas SOX2 or ClC­3 overexpression promoted PTX resistance. Mechanistically, SOX2 bound to the promoter of ClC­3 and enhanced the transcriptional activation of ClC­3 expression by CUT&Tag assays, CUT&Tag qPCR and luciferase reporter. In summary, the present findings defined ClC­3 as an important downstream effector of SOX2 and ClC­3 and SOX2 contributed to PTX resistance. Targeting SOX2 and its downstream effector ClC­3 increased the sensitivity of NSCLC cells to PTX treatment, which provided potential therapeutic strategies for patients with NSCLC with PTX resistance.

CLC-3 and SOX2 regulate the cell cycle in DU145 cells.

Sex determining region Y-box 2 (SOX2) is a transcription factor that serves a role in numerous different types of malignant cancer. Altered expression of chloride channel proteins has been described in a variety of malignancies. However, the association between SOX2 and chloride channel proteins is not yet fully understood. The present study investigated the association between SOX2 and chloride voltage-gated channel 3 (CLC-3) in prostate cancer. Flow cytometry demonstrated that the inactivation of CLC-3 or SOX2 arrested cell cycle progression in the G0/G1 phase. Furthermore, CLC-3 was observed to bind to SOX2, and vice versa, by co-immunoprecipitation. SOX2 appears to initiate and maintain prostate cancer tumorigenesis, in part, by modulating the cell cycle. These findings indicate the potential of SOX2 and CLC-3 as targets for the development of multi-targeted therapeutics.

DNA-PK inhibition synergizes with oncolytic virus M1 by inhibiting antiviral response and potentiating DNA damage.

Oncolytic virotherapy is a promising therapeutic strategy that uses replication-competent viruses to selectively destroy malignancies. However, the therapeutic effect of certain oncolytic viruses (OVs) varies among cancer patients. Thus, it is necessary to overcome resistance to OVs through rationally designed combination strategies. Here, through an anticancer drug screening, we show that DNA-dependent protein kinase (DNA-PK) inhibition sensitizes cancer cells to OV M1 and improves therapeutic effects in refractory cancer models in vivo and in patient tumour samples. Infection of M1 virus triggers the transcription of interferons (IFNs) and the activation of the antiviral response, which can be abolished by pretreatment of DNA-PK inhibitor (DNA-PKI), resulting in selectively enhanced replication of OV M1 within malignancies. Furthermore, DNA-PK inhibition promotes the DNA damage response induced by M1 virus, leading to increased tumour cell apoptosis. Together, our study identifies the combination of DNA-PKI and OV M1 as a potential treatment for cancers.

Genistein has the function of alleviating and treating disseminated intravascular coagulation caused by lipopolysaccharide.

Symptoms of disseminated intravascular coagulation (DIC) include thromboembolism, acute attrition bleeding and multiple organ failure. Genistein isolated from leguminous plants has been shown to be effective in oxidation resistance and tumor inhibition. The present study was designed to evaluate the therapeutic effects of genistein in DIC and preliminarily discuss the mechanisms regarding the anti-inflammatory and anticoagulant effect of genistein. Swiss mice were randomly divided into the following groups-(1) lipopolysaccharide (LPS), (2) genistein, (3) dimethyl sulfoxide (DMSO, the non-major solvent component of genistein), (4) DMSO + LPS, (5) saline control group, and (6) heparin control group. LPS was injected intraperitoneally in all the groups except the DMSO group and saline control group. Our results significantly showed that the morphological structure of the liver and kidneys was improved and the fiber protein deposition was decreased, with remarkable improvement of coagulation indicators, function indicators and inflammatory factors in the genistein treatment group compared with the LPS group. In vitro phosphorylated-nuclear factor kappa-light-chain-enhancer of activated B cells and interleukin-6 were obviously reduced in the genistein treatment group compared with the LPS group in RAW 264.7 murine macrophage cells. All the results suggested that genistein has the function of alleviating and treating LPS-induced DIC by anti-inflammatory and anticoagulation effects. We tentatively propose that genistein is a potential drug for auxiliary treatment of DIC.

Atractylenolide â protects against lipopolysaccharide-induced disseminated intravascular coagulation by anti-inflammatory and anticoagulation effect.

OBJECTIVE: To investigate whether atractylenolide Ⅰ (ATL-Ⅰ) has protective effect on lipopolysaccharide (LPS)-induced disseminated intravascular coagulation (DIC) in vivo and in vitro, and explore whether NF-κB signaling pathway is involved in ATL-Ⅰ treatment. METHODS: New Zealand white rabbits were injected with LPS through marginal ear vein over a period of 6 h at a rate of 600 µg/kg (10 mL/h). Similarly, in the treatment groups, 1.0, 2.0, or 5.0 mg/kg ATL-Ⅰ were given. Both survival rate and organ function were tested, including the level of alanine aminotransferase (ALT), blood urine nitrogen (BUN), and TNF-α were examined by ELISA. Also hemostatic and fibrinolytic parameters in serum were measured. RAW 264.7 macrophage cells were administered with control, LPS, LPS + ATL-Ⅰ and ATL-Ⅰ alone, and TNF-α, phosphorylation (P)-IκBα, phosphorylation (P)-NF-κB (P65) and NF-κB (P65) were determined by Western blot. RESULTS: The administration of LPS resulted in 73.3% mortality rate, and the increase of serum TNF-α, BUN and ALT levels. When ATL-Ⅰ treatment significantly increased the survival rate of LPS-induced DIC model, also improved the function of blood coagulation. And protein analysis indicated that ATL-I remarkably protected liver and renal as decreasing TNF-α expression. In vitro, ATL-I obviously decreased LPS-induced TNF-α production and the expression of P-NF-κB (P65), with the decrease of P-IκBα. CONCLUSIONS: ATL-Ⅰ has protective effect on LPS-induced DIC, which can elevate the survival rate, reduce organ damage, improve the function of blood coagulation and suppress TNF-α expression by inhibiting the activation of NF-κB signaling pathway.