ABSTRACT
PURPOSE: Glioblastoma (GBM) is a rapidly growing tumor in the central nervous system with altered metabolism. Depleting the bioenergetics of tumors with biguanides have been suggested as an effective therapeutic approach for treating GBMs. The purpose of this study was to determine the effects of IM1761065, a novel biguanide with improved pharmacokinetics, on GBM-tumorspheres (TSs). METHODS: The biological activities of IM1761065 on GBM-TSs, including their effects on viability, ATP levels, cell cycle, stemness, invasive properties, and transcriptomes were examined. The in vivo efficacy of IM1761065 was tested in a mouse orthotopic xenograft model. RESULTS: IM1761065 decreased the viability and ATP levels of GBM-TSs in a dose-dependent manner, and reduced basal and spare respiratory capacity in patient-derived GBM-TS, as measured by the oxygen consumption rate. Sphere formation, expression of stemness-related proteins, and invasive capacity of GBM-TSs were also significantly suppressed by IM1761065. A gene-ontology comparison of IM1761065-treated groups showed that the expression levels of stemness-related, epithelial mesenchymal transition-related, and mitochondrial complex I genes were also significantly downregulated by IM1761065. An orthotopic xenograft mouse model showed decreased bioluminescence in IM1761065-treated cell-injected mice at 5 weeks. IM1761065-treated group showed longer survival than the control group (P = 0.0289, log-rank test). CONCLUSION: IM1761065 is a potent inhibitor of oxidative phosphorylation. The inhibitory effect of IM1761065 on the bioenergetics of GBM-TS suggests that this novel compound could be used as a new drug for the treatment of GBM.
Subject(s)
Biguanides , Brain Neoplasms , Energy Metabolism , Glioblastoma , Adenosine Triphosphate/metabolism , Animals , Biguanides/pharmacology , Brain Neoplasms/drug therapy , Brain Neoplasms/metabolism , Brain Neoplasms/pathology , Cell Line, Tumor , Energy Metabolism/drug effects , Glioblastoma/drug therapy , Glioblastoma/metabolism , Glioblastoma/pathology , Humans , Mice , Xenograft Model Antitumor AssaysABSTRACT
The critical role of the Hippo pathway has been recently investigated in various cancers, but little is known about its role in glioblastoma (GBM). In order to evaluate the clinical relevance of the Hippo pathway in GBM, we generated a core gene expression signature from four different previously-established silence of Hippo pathway (SOH) signatures. Based on a newly generated core SOH signature, a SOH and active Hippo pathway (AH) was predicted in GBM samples from The Cancer Genome Atlas (TCGA) and validated in a separate cohort. A comparative analysis was performed on multi-panel genomic datasets from TCGA and the possible association of SOH with immune activity and epithelial mesenchymal transition was also evaluated. The SOH signature was associated with poor prognosis in GBM in both cohorts. Expression levels of CTGF and CYR61, the most reliable and well-known downstream targets of YAP1, were markedly increased in the SOH subgroup of GBM patients. SOH signature was strongly associated with a high immune signature score and mesenchymal features. Genes differentially expressed between SOH and AH groups revealed many markers for inhibitory immune checkpoints and M2-polarized macrophages were upregulated in the SOH subgroup, suggesting that SOH may induce the resistance of cancer cells to host immune response in GBM. In summary, SOH is significantly associated with the poor prognosis of GBM patients and is possibly mediated by pro-tumoral immunosuppression.
Subject(s)
Brain Neoplasms/genetics , Glioblastoma/genetics , Immunosuppression Therapy/methods , Protein Serine-Threonine Kinases/genetics , Brain Neoplasms/metabolism , Female , Gene Expression Regulation, Neoplastic , Glioblastoma/metabolism , Hippo Signaling Pathway , Humans , MaleABSTRACT
Background: Targeted approaches for treating glioblastoma (GBM) attempted to date have consistently failed, highlighting the imperative for treatment strategies that operate on different mechanistic principles. Bioenergetics deprivation has emerged as an effective therapeutic approach for various tumors. We have previously found that cancer cells preferentially utilize cytosolic NADH supplied by aldehyde dehydrogenase (ALDH) for ATP production through oxidative phosphorylation (OxPhos). This study is aimed at examining therapeutic responses and underlying mechanisms of dual inhibition of ALDH and OxPhos against GBM. Methods: For inhibition of ALDH and OxPhos, the corresponding inhibitors, gossypol and phenformin were used. Biological functions, including ATP levels, stemness, invasiveness, and viability, were evaluated in GBM tumorspheres (TSs). Gene expression profiles were analyzed using microarray data. In vivo anticancer efficacy was examined in a mouse orthotopic xenograft model. Results: Combined treatment of GBM TSs with gossypol and phenformin significantly reduced ATP levels, stemness, invasiveness, and cell viability. Consistently, this therapy substantially decreased expression of genes associated with stemness, mesenchymal transition, and invasion in GBM TSs. Supplementation of ATP using malate abrogated these effects, whereas knockdown of ALDH1L1 mimicked them, suggesting that disruption of ALDH-mediated ATP production is a key mechanism of this therapeutic combination. In vivo efficacy confirmed remarkable therapeutic responses to combined treatment with gossypol and phenformin. Conclusion: Our findings suggest that dual inhibition of tumor bioenergetics is a novel and effective strategy for the treatment of GBM.
Subject(s)
Aldehyde Dehydrogenase/antagonists & inhibitors , Brain Neoplasms/prevention & control , Electron Transport Complex I/antagonists & inhibitors , Energy Metabolism/drug effects , Glioblastoma/prevention & control , Neoplastic Stem Cells/drug effects , Oxidative Phosphorylation/drug effects , Adenosine Triphosphate/metabolism , Animals , Biomarkers, Tumor/genetics , Brain Neoplasms/metabolism , Brain Neoplasms/pathology , Cell Proliferation , Contraceptive Agents, Male/pharmacology , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Glioblastoma/metabolism , Glioblastoma/pathology , Gossypol/pharmacology , Humans , Hypoglycemic Agents/pharmacology , Male , Mice , Mice, Nude , Mitochondria/drug effects , Mitochondria/metabolism , Mitochondria/pathology , Neoplasm Invasiveness , Neoplastic Stem Cells/metabolism , Neoplastic Stem Cells/pathology , Phenformin/pharmacology , Prognosis , Survival Rate , Xenograft Model Antitumor AssaysABSTRACT
OBJECTS: Marrow stromal cells (MSCs) have been shown to have the capacity of orthodox and unorthodox plasticity. In this study, the authors tried to access in vitro cytotoxicity of MSCs from rat and also to differentiate MSCs into immune effector cell. METHODS: Rat MSCs (rMSCs) were isolated by standard methodology and were activated by interleukin-2 (IL-2), interleukin-15 (IL-15), granulocyte macrophage colony stimulating factor, and combinations, which were effector cells. Cytotoxicity of rMSCs and activated rMSCs against the target cells (9L rat glioma cell line) was estimated using visual survival cell assay. Phenotypes of these various activated cells were determined using flow cytometry. The secreted protein from effector cells was estimated by enzyme-linked immunosorbent assay. The expression of immune response-related genes in activated cells was measured. RESULTS: There was a significant cytotoxicity of rMSCs activated with various cytokine combinations. After various cytokine activations of rMSCs, the population of immune effector cells (CD8, CD161a) and immune reaction-related proteins (IL-4, gamma-INF) might increase. Apoptosis may be one of the lysis mechanisms of target cells by activated rMSCs. The contributing genes could be gamma-INF, FasL, and perforin. CONCLUSION: This study suggests that rMSC may be used as adoptive transfer therapy in patients suffering from malignant brain tumor, but we have to investigate orthotopic animal study for the proper translation.