Oxidative stress regulates cellular bioenergetics in esophageal squamous cell carcinoma cell

Metabolic subtypes and immune landscapes in esophageal squamous cell carcinoma: prognostic implications and potential for personalized therapies

BACKGROUND

This study aimed to identify metabolic subtypes in ESCA, explore their relationship with immune landscapes, and establish a metabolic index for accurate prognosis assessment.

METHODS

Clinical, SNP, and RNA-seq data were collected from 80 ESCA patients from the TCGA database and RNA-seq data from the GSE19417 dataset. Metabolic genes associated with overall survival (OS) and progression-free survival (PFS) were selected, and k-means clustering was performed. Immune-related pathways, immune infiltration, and response to immunotherapy were predicted using bioinformatic algorithms. Weighted gene co-expression network analysis (WGCNA) was conducted to identify metabolic genes associated with co-expression modules. Lastly, cell culture and functional analysis were performed using patient tissue samples and ESCA cell lines to verify the identified genes and their roles.

RESULTS

Molecular subtypes were identified based on the expression profiles of metabolic genes, and univariate survival analysis revealed 163 metabolic genes associated with ESCA prognosis. Consensus clustering analysis classified ESCA samples into three distinct subtypes, with MC1 showing the poorest prognosis and MC3 having the best prognosis. The subtypes also exhibited significant differences in immune cell infiltration, with MC3 showing the highest scores. Additionally, the MC3 subtype demonstrated the poorest response to immunotherapy, while the MC1 subtype was the most sensitive. WGCNA analysis identified gene modules associated with the metabolic index, with SLC5A1, NT5DC4, and MTHFD2 emerging as prognostic markers. Gene and protein expression analysis validated the upregulation of MTHFD2 in ESCA. MTHFD2 promotes the progression of ESCA and may be a potential therapeutic target for ESCA.

CONCLUSION

The established metabolic index and identified metabolic genes offer potential for prognostic assessment and personalized therapeutic interventions for ESCA, underscoring the importance of targeting metabolism-immune interactions in ESCA. MTHFD2 promotes the progression of ESCA and may be a potential therapeutic target for ESCA.

Promotion of NAD+ recycling by the hypoxia-induced shift in the lactate dehydrogenase isozyme profile reduces the senescence of human bone marrow-derived endothelial progenitor cells

Expansion of bone marrow-derived endothelial progenitor cells (EPCs) in vitro to obtain required cell numbers for therapeutic applications faces the challenge of growing cell senescence under the traditional normoxic culture condition. We previously found that 1% O2 hypoxic culture condition is favorable for reducing senescence of EPCs, but the mechanisms underlying the favorability are still unclear. Here, we found that, compared with normoxia, hypoxia induced a shift in lactate dehydrogenase (LDH) isozyme profile, which manifested as decreased LDH2 and LDH1 and increased LDH5, LDH4 and total LDHs. Moreover, under hypoxia, EPCs presented higher LDH activity, which could promote the conversion of pyruvate to lactate, as well as a higher level of NAD+, Bcl2 interacting protein 3 (BNIP3) expression and mitophagy. Additionally, under hypoxia, knock-down of the LDHA subunit increased the LDH2 and LDH1 levels and knock-down of the LDHB subunit increased the LDH5 level, while the simultaneous knock-down of LDHA and LDHB reduced total LDHs and NAD+ level. Inhibition of NAD+ recycling reduced BNIP3 expression and mitophagy and promoted cell senescence. Taken together, these data demonstrated that 1% O2 hypoxia induces a shift in the LDH isozyme profile, promotes NAD+ recycling, increases BNIP3 expression and mitophagy, and reduces EPC senescence. Our findings contribute to a better understanding of the connection between hypoxic culture conditions and the senescence of bone marrow-derived EPCs and provide a novel strategy to improve in vitro expansion of EPCs.

Oxidative stress genes in patients with esophageal squamous cell carcinoma: construction of a novel prognostic signature and characterization of tumor microenvironment infiltration

Background

Oxidative stress plays an important role in the progression of various types of tumors. However, its role in esophageal squamous cell carcinoma (ESCC) has seldom been explored. This study aimed to discover prognostic markers associated with oxidative stress in ESCC to improve the prediction of prognosis and help in the selection of effective immunotherapy for patients.

Results

A consensus cluster was constructed using 14 prognostic differentially expressed oxidative stress-related genes (DEOSGs) that were remarkably related to the prognosis of patients with ESCC. The infiltration levels of neutrophils, plasma cells, and activated mast cells, along with immune score, stromal score, and estimated score, were higher in cluster 1 than in cluster 2. A prognostic signature based on 10 prognostic DEOSGs was devised that could evaluate the prognosis of patients with ESCC. Calculated risk score proved to be an independent clinical prognostic factor in the training, testing, and entire sets. P53 signaling pathway was highly enriched in the high-risk group. The calculated risk score was positively related to the infiltration levels of resting mast cells, memory B cells, and activated natural killer (NK) cells and negatively associated with the infiltration levels of M1 and M2 macrophages. The relationship between clinical characteristics and risk score has not been certified. The half-maximal inhibitory concentration (IC50) values for sorafenib and gefitinib were lower for patients in the low-risk group.

Conclusion

Our prognostic signature based on 10 prognostic DEOSGs could predict the disease outcomes of patients with ESCC and had strong clinical value. Our study improves the understanding of oxidative stress in tumor immune microenvironment (TIME) and provides insights for developing improved and efficient immunotherapy strategies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12859-022-04956-9.

Effect of TRPM2-Mediated Calcium Signaling on Cell Proliferation and Apoptosis in Esophageal Squamous Cell Carcinoma

Esophageal squamous cell carcinoma (ESCC) is the sixth leading cause of death due to cancer, indicating that finding new therapeutic targets or approaches for ESCC treatment is imperative. Transient Receptor Potential cation channel subfamily M, member 2 (TRPM2) is a calcium-permeable, nonselective cation channel that responds to reactive oxygen species (ROS), which are found in the tumor microenvironment and are important regulators of tumorigenesis, cell proliferation, apoptosis, and the therapeutic response. Here, we used immunohistochemical analysis of tumor tissue derived from patients with ESCC to find that the TRPM2 channel protein expression level was increased in tumor tissue compared with adjacent normal tissue. Intracellular calcium concentration measurements, western blotting, and ROS and cell viability assays were used with a human ESCC cell line (TE-1 cells) to find that TRPM2 participated in the ROS hydrogen peroxide-induced increase in intracellular calcium. This increased calcium inhibited cell proliferation and enhanced apoptosis. Pretreatment of cells with the anticancer agent 5-fluorouracil (5-FU) significantly increased ROS production, which potentiated TRPM2-mediated calcium signaling, decreased cell proliferation, and increased apoptosis in TE-1 cells, suggesting that the therapeutic effect of 5-FU in ESCC cells may be mediated by the TRPM2 channel-mediated calcium influx. These findings offer a potential treatment target and provide mechanistic insight into the therapeutic effects of 5-FU in patients with ESCC.

Cross-talk between oxidative stress signaling and microRNA regulatory systems in carcinogenesis: Focused on gastrointestinal cancers

Molecular mechanisms underlying development and progression of gastrointestinal (GI) cancers are mediated by both oxidative stress (OS) and microRNAs (miRNAs) involvement. Notably, OS signaling may regulate the expression of miRNAs, and miRNAs function as imperative players in OS-initiated tumors. Given the defined biological roles of both OS systems and miRNAs in GI carcinogenesis, a possible interplay between these two key cellular networks is considered. A growing body of evidence has indicated a reciprocal connection between OS signaling pathways and miRNA regulatory machines in GI cancer development and progression. Illumination of the molecular cross-talking between miRNAs and the OS would improve our pathophysiological insight into carcinogens. Also, understanding the molecular mechanisms in which these systems are reciprocally regulated may imply in future medical practice mainly GI cancer therapy. Nowadays, therapeutic strategies focusing on miRNA and OS in GI cancer treatment are increasingly delineated. Since the use of antioxidants is limited owing to the contrasting consequences of OS signaling in cancer, the discovery of OS-responsive miRNAs may provide a potential new strategy to overcome OS-mediated GI carcinogenesis. Given the possible interaction between OS and miRNAs in GI cancers, this review aimed to elucidate the existing evidence on the interaction between OS and miRNA regulatory machinery and its role in GI carcinogenesis. In this regard, we will illustrate the function of miRNAs which target OS systems during homeostasis and tumorigenesis. We also discuss the biological cross-talk between OS systems and miRNAs and corresponding cell signaling pathways.

Assessment of PPARGC1A, PPARGC1B, and PON1 Genetic Polymorphisms in Esophageal Squamous Cell Carcinoma Susceptibility in the Eastern Chinese Han Population: A Case-Control Study Involving 2351 Subjects

Previous studies suggested that alterations in the energy metabolism might be underlying cancer initiation and progression. Polymorphisms of genes involved in energy metabolism regulation, such as peroxisome proliferator-activated receptor gamma coactivator 1α (PPARGC1A), -β (PPARGC1B), and paraoxonase 1 (PON1), might confer susceptibility to esophageal squamous cell carcinoma (ESCC) and partially explain its pathogenesis. We investigated the effects of several single nucleotide polymorphisms (SNPs) in three metabolic-related genes (e.g., PPARGC1A, PPARGC1B, and PON1) on ESCC susceptibility. In total, 829 patients with sporadic ESCC and 1522 nontumor controls were enrolled in the study. SNPs were genotyped using PCR-ligase detection reaction. Our study revealed that the PPARGC1A rs3736265 G/A SNP significantly increased the risk for ESCC (GA vs. GG: adjusted odds ratio [OR] = 1.25, 95% confidence interval [95% CI] = 1.02-1.54, p = 0.034; GA+AA vs. GG: adjusted OR = 1.25, 95% CI = 1.03-1.52, p = 0.027]. In addition, a stratified analysis revealed that the PPARGC1A rs3736265 SNP was correlated with the development of ESCC in male and nondrinking subgroups. We also confirmed that the PPARGC1B rs17572019 G/A SNP promoted the risk of ESCC in subgroup with high alcohol intake. The PPARGC1A rs8192678 C/T polymorphism decreased the susceptibility of ESCC in men. These findings highlight that polymorphisms in PPARGC1A and PPARGC1B may contribute to ESCC susceptibility. In the future, further well-designed epidemiological studies are needed to confirm our findings.

Mechanisms of lung toxicity induced by biomass burning aerosols

BACKGROUND

Carbonaceous aerosols emitted from indoor and outdoor biomass burning are major risk factors contributing to the global burden of disease. Wood tar aerosols, namely, tar ball particles, compose a substantial fraction of carbonaceous emissions, especially from biomass smoldering. However, their health-related impacts and toxicity are still not well known. This study investigated the toxicity of the water-soluble fraction of pyrolyzed wood tar aerosols in exposed mice and lung epithelial cells.

RESULTS

Mice exposed to water-soluble wood tar aerosols showed increased inflammatory and oxidative stress responses. Bronchial epithelial cells exposed to the same water-soluble wood tar aerosols showed increased cell death with apoptotic characteristics. Alterations in oxidative status, including changes in reactive oxygen species (ROS) levels and reductions in the expression of antioxidant genes related to the transcription factor Nrf2, were observed and were confirmed by increased levels of MDA, a lipid peroxidation adduct. Damage to mitochondria was observed as an early event responsible for the aforementioned changes.

CONCLUSIONS

The toxicity and health effect-related mechanisms of water-soluble wood tar were investigated for the first time in the context of biomass burning. Wood tar particles may account for major responses such as cell death, oxidative stress, supression of protection mechnaisms and mitochondrial damaged cause by expsoure to biomass burning aerosols.

Protective effect of propofol on hydrogen peroxide-induced human esophageal carcinoma via blocking the Wnt/β-catenin signaling pathway

Objective(s):

To analyze the potential influences of propofol on the oxidative stress of H₂O₂-induced human esophageal squamous cell carcinoma (ESCC) Eca109 cell through mediating the Wnt/β-catenin signaling pathway.

Materials and Methods:

Eca109 cells were classified into 5 groups: Control group, H₂O₂ group, Propofol + H₂O₂ group, Dkk1 (Dickkopf-1, Wnt/β-catenin pathway antagonist) + H₂O₂ group, and Propofol + LiCl (Lithium chloride, Wnt/β-catenin pathway agonist) + H₂O₂ group. Western blotting was performed to determine the protein expressions, flow cytometry to measure the content of ROS, immunofluorescence staining to detect the oxidative DNA damage, as well as MTT, AnnexinV-FITC/PI, Wound-healing, and Transwell assays to test the biological characteristics of Eca109 cells.

Results:

H₂O₂ resulted in the increased nuclear and cytoplasmatic expression of β-catenin, reduced p-GSK3β expression, up-regulated ROS content, and induced oxidative DNA damage in Eca109 cells. Moreover, Eca109 cells treated with H₂O₂ alone had enhanced cell proliferation and metastasis but decreased cell apoptosis, as compared with those without any treatment; meanwhile, the declined Cyt C, Bax, and cleaved caspase-3, as well as the elevated Bcl-2 were also observed in Eca109 cells in the H₂O₂ group, which were reversed by Propofol or Dkk1. Moreover, Propofol could inhibit the effect of LiCl on activating the Wnt/β-catenin signaling pathway in H₂O₂-induced Eca109 cells.

Conclusion:

Propofol elicits protective effects to inhibit H₂O₂-induced proliferation and metastasis and promote apoptosis of Eca109 cells via blocking the Wnt/β-catenin pathway, offering a possible therapeutic modality for ESCC.