Identification and validation of a novel prognostic signature based on mitochondria and oxidative stress related genes for glioblastoma

Divergent ferroptotic pathways in breast cancer cells: IGFBP6-regulated mitochondrial lipid peroxidation under erastin and omega-3 DHA treatment

Breast cancer remains a major challenge and new therapeutic approaches are needed for its treatment. Ferroptosis is considered a promising alternative cell death mechanism to eliminate resistant cancer cells. In previous works, we identified that lower IGFBP6 gene expression in tumor tissue corresponds to a worse prognosis for breast cancer patients and, at the same, time makes them more sensitive to ferroptosis. In this study, we further investigated the mechanism of ferroptosis induction in IGFBP6 knockdown and control MDA-MB-231 breast cancer cells by the canonical ferroptosis inducer erastin and omega-3 docosahexaenoic acid (DHA). Our results indicate that there is a significant overlap between the mechanisms of action of both of these molecules, as they regulate the same subset of genes, and their action can be inhibited by canonical ferroptosis inhibitors. On the other hand, we also observed significant differences between the effects of erastin and DHA. The most notable of these are the additional activation of apoptosis-related genes by DHA and its minor peroxidation of mitochondrial lipid membranes. Interestingly, our kinetic analysis of ferroptosis induction showed that IGFBP6 knockdown cells began to die earlier and could hardly be rescued from erastin-induced ferroptosis by mitochondrial antioxidant SkQ1, in contrast to control cells. Overall, our data suggest that the action of DHA is less dependent on mitochondrial membrane peroxidation during ferroptosis induction, and this molecule can be a promising candidate for the treatment of breast cancer, especially in the case of reduced IGFBP6 gene expression in cancer cells.

A novel golgi related genes based correlation prognostic index can better predict the prognosis of glioma and responses to immunotherapy

BACKGROUND

The Golgi apparatus (GA) serves as the center of protein and lipid synthesis and modification within cells, playing a crucial role in regulating diverse cellular processes as a signaling hub. Dysregulation of GA function can give rise to a range of pathological conditions, including tumors. Notably, mutations in Golgi-associated genes (GARGs) are frequently observed in various tumors, and these mutations have been implicated in promoting tumor metastasis. However, the precise relationship between GARGs and glioma, a type of brain tumor, remains poorly understood. Therefore, the objective of this investigation was to assess the prognostic significance of GARGs in glioma and evaluate their impact on the immune microenvironment.

METHODS

The expression of GARGs was obtained from the TCGA and CGGA databases, encompassing a total of 1564 glioma samples (598 from TCGA and 966 from CGGA). Subsequently, a risk prediction model was constructed using LASSO regression and Cox analysis, and its efficacy was assessed. Additionally, qRT-PCR was employed to validate the expression of GARGs in relation to glioma prognosis. Furthermore, the association between GARGs and immunity, mutation, and drug resistance was investigated.

RESULTS

A selection of GARGs (SPRY1, CHST6, B4GALNT1, CTSL, ADCY3, GNL1, KIF20A, CHP1, RPS6, CLEC18C) were selected through differential expression analysis and Cox analysis, which were subsequently incorporated into the risk model. This model demonstrated favorable predictive efficiency, as evidenced by the area under the curve (AUC) values of 0.877, 0.943, and 0.900 for 1, 3, and 5-year predictions, respectively. Furthermore, the risk model exhibited a significant association with the tumor immune microenvironment and mutation status, as well as a diminished sensitivity to chemotherapy drugs. qRT-PCR analysis confirmed the up-regulation or down-regulation of the aforementioned genes in glioma.

CONCLUSION

The utilization of GARGs in our constructed model exhibits a high level of accuracy in prognosticating glioma and offers promising avenues for the development of therapeutic interventions targeting glioma.

Development of a Prognostic Risk Model Based on Oxidative Stress-related Genes for Platinum-resistant Ovarian Cancer Patients

INTRODUCTION

Ovarian Cancer (OC) is a heterogeneous malignancy with poor outcomes. Oxidative stress plays a crucial role in developing drug resistance. However, the relationships between Oxidative Stress-related Genes (OSRGs) and the prognosis of platinum-resistant OC remain unclear. This study aimed to develop an OSRGs-based prognostic risk model for platinum- resistant OC patients.

METHODS

Gene Set Enrichment Analysis (GSEA) was performed to determine the expression difference of OSRGs between platinum-resistant and -sensitive OC patients. Cox regression analyses were used to identify the prognostic OSRGs and establish a risk score model. The model was validated by using an external dataset. Machine learning was used to determine the prognostic OSRGs associated with platinum resistance. Finally, the biological functions of selected OSRG were determined via in vitro cellular experiments.

RESULTS

Three gene sets associated with oxidative stress-related pathways were enriched (p < 0.05), and 105 OSRGs were found to be differentially expressed between platinum-resistant and - sensitive OC (p < 0.05). Twenty prognosis-associated OSRGs were identified (HR: 0:562-5.437; 95% CI: 0.319-20.148; p < 0.005), and seven independent OSRGs were used to construct a prognostic risk score model, which accurately predicted the survival of OC patients (1-, 3-, and 5-year AUC=0.69, 0.75, and 0.67, respectively). The prognostic potential of this model was confirmed in the validation cohort. Machine learning showed five prognostic OSRGs (SPHK1, PXDNL, C1QA, WRN, and SETX) to be strongly correlated with platinum resistance in OC patients. Cellular experiments showed that WRN significantly promoted the malignancy and platinum resistance of OC cells.

CONCLUSION

The OSRGs-based risk score model can efficiently predict the prognosis and platinum resistance of OC patients. This model may improve the risk stratification of OC patients in the clinic.

6-Gingerol Induced Apoptosis and Cell Cycle Arrest in Glioma Cells via MnSOD and ERK Phosphorylation Modulation

6-gingerol, a bioactive compound from ginger, has demonstrated promising anticancer properties across various cancer models by inducing apoptosis and inhibiting cell proliferation and invasion. In this study, we explore its mechanisms against glioblastoma multiforme (GBM), a notably aggressive and treatment-resistant brain tumor. We found that 6-gingerol crosses the blood-brain barrier more effectively than curcumin, enhancing its potential as a therapeutic agent for brain tumors. Our experiments show that 6-gingerol reduces cell proliferation and triggers apoptosis in GBM cell lines by disrupting cellular energy homeostasis. This process involves an increase in mitochondrial reactive oxygen species (mtROS) and a decrease in mitochondrial membrane potential, primarily due to the downregulation of manganese superoxide dismutase (MnSOD). Additionally, 6-gingerol reduces ERK phosphorylation by inhibiting EGFR and RAF, leading to G1 phase cell cycle arrest. These findings indicate that 6-gingerol promotes cell death in GBM cells by modulating MnSOD and ROS levels and arresting the cell cycle through the ERFR-RAF-1/MEK/ERK signaling pathway, highlighting its potential as a therapeutic agent for GBM and setting the stage for future clinical research.

Antitumor Effect of Butia odorata Hydroalcoholic Extract on C6 and U87MG Glioma Cell Lines: Impact on Redox Status and Inflammation Signaling

Among the spectrum of gliomas, glioblastoma stands out as the most aggressive brain tumor affecting the central nervous system. In addressing this urgent medical challenge, exploring therapeutic alternatives becomes imperative to enhance the patient's prognosis. In this regard, Butia odorata (BO) fruit emerges as a promising candidate due to its array of bioactive compounds, including flavonoids, phenolic acids, and carotenoids, known for their antioxidant, anti-inflammatory, and antitumor properties. Thus, this study aimed to investigate the impact of standardized hydroalcoholic extract of BO on rat C6 and human U87MG glioma cell lines. Cells were exposed to varying extract concentrations (125-2000 μg/mL) for intervals of 0, 2, 4, 6, 24, 48, or 72 h. Then, cell viability, proliferation, colony formation, redox equilibrium parameters, cell migration, and the relative mRNA expression of genes related to gliomagenesis were evaluated. Our findings revealed a reduction in viability, proliferation, colony formation, reactive oxygen species, and nitrite levels in both glioma cell lines upon exposure to the extract. Conversely, an increase in sulfhydryl content and the activity of superoxide dismutase and catalase were observed in both glioma cell lines. No significant changes in viability and proliferation were observed in astrocytes. Furthermore, in the C6 cells only, the BO extract reduced the migration and downregulated the relative mRNA expression of matrix metalloproteinase-2, O6-methylguanine-DNA methyltransferase, nuclear factor-kappa B, interleukin-6 genes, and upregulated caspase-3 gene. These results underscore the promising anti-glioma potential of BO extract, attributed to its diverse bioactive composition.

Targeting DNM1L/DRP1-FIS1 axis inhibits high-grade glioma progression by impeding mitochondrial respiratory cristae remodeling

BACKGROUND

The dynamics of mitochondrial respiratory cristae (MRC) and its impact on oxidative phosphorylation (OXPHOS) play a crucial role in driving the progression of high-grade glioma (HGG). However, the underlying mechanism remains unclear.

METHODS

In the present study, we employed machine learning-based transmission electron microscopy analysis of 7141 mitochondria from 54 resected glioma patients. Additionally, we conducted bioinformatics analysis and multiplex immunohistochemical (mIHC) staining of clinical glioma microarrays to identify key molecules involved in glioma. Subsequently, we modulated the expression levels of mitochondrial dynamic-1-like protein (DNM1L/DRP1), and its two receptors, mitochondrial fission protein 1 (FIS1) and mitochondrial fission factor (MFF), via lentiviral transfection to further investigate the central role of these molecules in the dynamics of glioblastoma (GBM) cells and glioma stem cells (GSCs). We then evaluated the potential impact of DNM1L/DRP1, FIS1, and MFF on the proliferation and progression of GBM cells and GSCs using a combination of CCK-8 assay, Transwell assay, Wound Healing assay, tumor spheroid formation assay and cell derived xenograft assay employing NOD/ShiLtJGpt-Prkdcem26Cd52Il2rgem26Cd22/Gpt (NCG) mouse model. Subsequently, we validated the ability of the DNM1L/DRP1-FIS1 axis to remodel MRC structure through mitophagy by utilizing Seahorse XF analysis technology, mitochondrial function detection, MRC abundance detection and monitoring dynamic changes in mitophagy.

RESULTS

Our findings revealed that compared to low-grade glioma (LGG), HGG exhibited more integrated MRC structures. Further research revealed that DNM1L/DRP1, FIS1, and MFF played pivotal roles in governing mitochondrial fission and remodeling MRC in HGG. The subsequent validation demonstrated that DNM1L/DRP1 exerts a positive regulatory effect on FIS1, whereas the interaction between MFF and FIS1 demonstrates a competitive inhibition relationship. The down-regulation of the DNM1L/DRP1-FIS1 axis significantly impaired mitophagy, thereby hindering the remodeling of MRC and inhibiting OXPHOS function in glioma, ultimately leading to the inhibition of its aggressive progression. In contrast, MFF exerts a contrasting effect on MRC integrity, OXPHOS activity, and glioma progression.

CONCLUSIONS

This study highlights that the DNM1L/DRP1-FIS1 axis stabilizes MRC structures through mitophagy in HGG cells while driving their OXPHOS activity ultimately leading to robust disease progression. The inhibition of the DNM1L/DRP1-FIS1 axis hinders MRC remodeling and suppresses GBM progression. We propose that down-regulation of the DNM1L/DRP1-FIS1 axis could be a potential therapeutic strategy for treating HGG.

Cationic Polythiophene as Gene Carrier and Sonosensitizer for Sonodynamic Synergic Gene Therapy of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most lethal and highly malignant tumors. Sonodynamic therapy (SDT) is a new cancer treatment method. One of its unique advantages lies in the treatment of deep tumors due to its excellent tissue penetration ability caused by ultrasound (US). However, most sonosensitizers suffer from weak sonodynamic activity and poor tumor-targeting ability. In addition, small interfering RNA (siRNA) is a promising anticancer drug, and the efficacy of siRNA-based gene therapy largely depends on the cell impermeability of the gene carrier. Here, we designed and synthesized a cationic polythiophene derivative (PT2) that can be used as a siRNA carrier for gene therapy. Moreover, PT2 could generate singlet oxygen (1O2) and hydroxyl radicals (O2•-) under US irradiation, which suggests that PT2 could be used for SDT. Our study discovered that NUDT1 promoted HCC proliferation and inhibited intracellular ROS production. Therefore, si-NUDT1 was designed and synthesized. NUDT1 silencing can inhibit the proliferation of tumor cells and increase the production of intracellular ROS to further improve the efficacy of SDT. Then, si-NUDT1 assembled with PT2 and DSPE-PEG-FA to prepare a novel tumor-targeting nanodrug (PT2-siRNA@PEG-FA) for synergic SDT and gene therapy of HCC.

Prognostic relevance and validation of ARPC1A in the progression of low-grade glioma

Low-grade glioma (LGG) is a grade II-III glioma accompanied by distinct clinical and molecular characteristics and the studies related to its prognosis are still unclear. The objective of this study is to explore the involvement of mitochondrial-related genes SLBP, COMMD7, LSM4, TOMM34, RPP40, FKBP1A, ARPC1A, and TBCA for the prognosis of LGG. We detected differences in the expression of some of the genes by analyzing the bioinformatics dataset and combining it with RT-PCR experiments. Subsequently, a nomogram was constructed and validated for the clinical relevance of risk factors such as age, WHO grade, IDH mutation status, Ch.1p19q co-deletion status, and high and low expression of ARPC1A to predict the 1-, 3-, 5-year overall survival and prognostic relevance of ARPC1A. Gene set enrichment analysis was performed for the relevant datasets pertinent to the expression of ARPC1A to elucidate the cancer-promoting pathways involved in the LGG through KEGG and GO analysis. Transfection assays, CCK-8 assays, and flow cytometry were used to determine the proliferation rate, and apoptosis rate of the HS683 and SW1783 cell lines respectively. Western blotting was used to examine the involvement of the cancer-promoting activity of ARPC1A through MAPK signaling. In this study, the prognostic value of ARPC1A in LGG was found by bioinformatics analysis combined with experimental approach analysis and may be a significant independent risk factor. ARPC1A fosters a higher LGG proliferation rate that may control the MAP kinase signaling and could be a prominent biomarker for LGG. Future studies are warranted to explore its clinical implications.

Mitochondria-related chemoradiotherapy resistance genes-based machine learning model associated with immune cell infiltration on the prognosis of esophageal cancer and its value in pan-cancer

Esophageal cancer, known for its high incidence and low five-year survival rate, poses significant treatment challenges. A key aspect of this challenge is the close link between mitochondria and resistance to chemoradiotherapy (CRT). Currently, there is a scarcity of biomarkers for predicting CRT response and prognosis in esophageal cancer. Our study addresses this gap by developing a prognostic model that incorporates mitochondria-related CRT resistance (MRCRTR) genes, including CTSL, TBL1X, CLN8, MMP1, PDPN, and MRPL37. Survival analysis using Kaplan-Meier curves reveals that patients with high MRCRTR scores have lower survival rates than those with low scores. Utilizing a nomogram, we successfully predict the one-, two-, and three-year overall survival rates for esophageal cancer patients. Cox regression analysis confirms the MRCRTR score as an independent prognostic factor. Furthermore, our single-cell and correlation analyses suggested that MRCRTR genes might influence CRT resistance by modulating the immune microenvironment and impacting angiogenesis. Our pan-cancer analysis also indicates the potential applicability of MRCRTR scores to head and neck squamous cell carcinoma. The validation of these findings, conducted with samples from Xiang-ya Hospital, aligns closely with our bioinformatics results. Our study not only explores the role of MRCRTR genes in predicting the prognosis of esophageal cancer but also enhances the understanding of the interplay between CRT, mitochondria, and patient outcomes.

Identification of Hypoxia Prognostic Signature in Glioblastoma Multiforme Based on Bulk and Single-Cell RNA-Seq

Glioblastoma (GBM) represents a profoundly aggressive and heterogeneous brain neoplasm linked to a bleak prognosis. Hypoxia, a common feature in GBM, has been linked to tumor progression and therapy resistance. In this study, we aimed to identify hypoxia-related differentially expressed genes (DEGs) and construct a prognostic signature for GBM patients using multi-omics analysis. Patient cohorts were collected from publicly available databases, including the Gene Expression Omnibus (GEO), the Chinese Glioma Genome Atlas (CGGA), and The Cancer Genome Atlas-Glioblastoma Multiforme (TCGA-GBM), to facilitate a comprehensive analysis. Hypoxia-related genes (HRGs) were obtained from the Molecular Signatures Database (MSigDB). Differential expression analysis revealed 41 hypoxia-related DEGs in GBM patients. A consensus clustering approach, utilizing these DEGs' expression patterns, identified four distinct clusters, with cluster 1 showing significantly better overall survival. Machine learning techniques, including univariate Cox regression and LASSO regression, delineated a prognostic signature comprising six genes (ANXA1, CALD1, CP, IGFBP2, IGFBP5, and LOX). Multivariate Cox regression analysis substantiated the prognostic significance of a set of three optimal signature genes (CP, IGFBP2, and LOX). Using the hypoxia-related prognostic signature, patients were classified into high- and low-risk categories. Survival analysis demonstrated that the high-risk group exhibited inferior overall survival rates in comparison to the low-risk group. The prognostic signature showed good predictive performance, as indicated by the area under the curve (AUC) values for one-, three-, and five-year overall survival. Furthermore, functional enrichment analysis of the DEGs identified biological processes and pathways associated with hypoxia, providing insights into the underlying mechanisms of GBM. Delving into the tumor immune microenvironment, our analysis revealed correlations relating the hypoxia-related prognostic signature to the infiltration of immune cells in GBM. Overall, our study highlights the potential of a hypoxia-related prognostic signature as a valuable resource for forecasting the survival outcome of GBM patients. The multi-omics approach integrating bulk sequencing, single-cell analysis, and immune microenvironment assessment enhances our understanding of the intricate biology characterizing GBM, thereby potentially informing the tailored design of therapeutic interventions.

Identification of histone acetylation modification sites in the striatum of subchronically manganese-exposed rats

Aim: To explore the specific histone acetylation sites and oxidative stress-related genes that are associated with the pathogenesis of manganese toxicity. Methods: We employed liquid chromatography-tandem mass spectrometry and bioinformatics analysis to identify acetylated proteins in the striatum of subchronic manganese-intoxicated rats. Results: We identified a total of 12 differentially modified histone acetylation sites: H3K9ac, H3K14ac, H3K18ac, H3K56ac and H3K79ac were upregulated and H3K27ac, H3K36ac, H4K91ac, H4K79ac, H4K31ac, H2BK16ac and H2BK20ac were downregulated. Additionally, we found that CAT, SOD1 and SOD2 might be epigenetically regulated and involved in the pathogenesis of manganism. Conclusion: This study identified histone acetylation sites and oxidative stress-related genes associated with the pathogenesis of manganese toxicity, and these findings are useful in the search for potential epigenetic targets for manganese toxicity.

Mitochondrial dysfunction at the crossroad of cardiovascular diseases and cancer

A large body of evidence indicates the existence of a complex pathophysiological relationship between cardiovascular diseases and cancer. Mitochondria are crucial organelles whose optimal activity is determined by quality control systems, which regulate critical cellular events, ranging from intermediary metabolism and calcium signaling to mitochondrial dynamics, cell death and mitophagy. Emerging data indicate that impaired mitochondrial quality control drives myocardial dysfunction occurring in several heart diseases, including cardiac hypertrophy, myocardial infarction, ischaemia/reperfusion damage and metabolic cardiomyopathies. On the other hand, diverse human cancers also dysregulate mitochondrial quality control to promote their initiation and progression, suggesting that modulating mitochondrial homeostasis may represent a promising therapeutic strategy both in cardiology and oncology. In this review, first we briefly introduce the physiological mechanisms underlying the mitochondrial quality control system, and then summarize the current understanding about the impact of dysregulated mitochondrial functions in cardiovascular diseases and cancer. We also discuss key mitochondrial mechanisms underlying the increased risk of cardiovascular complications secondary to the main current anticancer strategies, highlighting the potential of strategies aimed at alleviating mitochondrial impairment-related cardiac dysfunction and tumorigenesis. It is hoped that this summary can provide novel insights into precision medicine approaches to reduce cardiovascular and cancer morbidities and mortalities.