DUOX1 Silencing in Mammary Cell Alters the Response to Genotoxic Stress

ZC3H13 reduced DUOX1-mediated ferroptosis in laryngeal squamous cell carcinoma cells through m6A-dependent modification

Laryngeal squamous cell carcinoma (LSCC) is the second most common head and neck cancer. To identify the link between ferroptosis and LSCC, we targeted the dual oxidase 1 (DUOX1) gene. This study aimed to reveal the intrinsic mechanism by which the DUOX1-zinc-finger CCCH domain-containing protein 13 (ZC3H13) ferroptosis axis affected the LSCC process. GEPIA was used to investigate the expression of DUOX1 in LSCC, and the expression levels of DUOX1 and ZC3H13 were manipulated by overexpression and RNA interference. MTT assay was used to detect cell proliferation. Chromatin immunoprecipitation (CHIP) detected the binding of DUOX1 and ZC3H13, and ROS assessment and intracellular Fe2+ content determination were performed to examine the ferroptosis. MeRIP was used to analyze the m6A methylation of DUOX1. Ferroptosis-related proteins were detected by qRT-PCR. DUOX1 was found to be poorly expressed in LSCC cells, low DUOX1 level promoted LSCC cell proliferation, and low ZC3H13 level decreased LSCC cell proliferation. Besides, there was an interaction between DUOX1 and ZC3H13. DUOX1 could inhibit the expression levels of ferroptosis-related genes GPX4 and F1H1 in LSCC cells DUOX1 inhibited the expression levels of ROS and ferroptosis-related genes GPX4 and F1H1 and increased intracellular iron content in LSCC cells, but ZC3H13 reversed this phenomenon by inhibiting DUOX1 gene through m6A methylation modification. ZC3H13 reduced DUOX1-mediated ferroptosis in LSCC cells through m6A-dependent modification. The regulatory pathway of DUOX1 and ferroptosis are potential targets for designing diagnostic and combination therapeutic strategies for LSCC patients.

Development and Validation of a Tumor Mutation Burden-Related Immune Prognostic Signature for Ovarian Cancers

Ovarian cancer (OC), one of the most common malignancies of the female reproductive system, is characterized by high incidence and poor prognosis. Tumor mutation burden (TMB), as an important biomarker that can represent the degree of tumor mutation, is emerging as a key indicator for predicting the efficacy of tumor immunotherapy. In our study, the gene expression profiles of OC were downloaded from TCGA and GEO databases. Subsequently, we analyzed the prognostic value of TMB in OC and found that a higher TMB score was significantly associated with a better prognosis (p = 0.004). According to the median score of TMB, 9 key TMB related immune prognostic genes were selected by LASSO regression for constructing a TMB associated immune risk score (TMB-IRS) signature, which can effectively predict the prognosis of OC patients (HR = 2.32, 95% CI = 1.68–3.32; AUC = 0.754). Interestingly, TMB-IRS is also closely related to the level of immune cell infiltration and immune checkpoint molecules (PD1, PD-L1, CTLA4, PD-L2) in OC. Furthermore, the nomogram combined with TMB-IRS and a variety of clinicopathological features can more comprehensively evaluate the prognosis of patients. In conclusion, we explored the relationship between TMB and prognosis and validated the TMB-IRS signature based on TMB score in an independent database (HR = 1.60, 95% CI = 1.13–2.27; AUC = 0.639), which may serve as a novel biomarker for predicting OC prognosis as well as possible therapeutic targets.

Identification of Five Cytotoxicity-Related Genes Involved in the Progression of Triple-Negative Breast Cancer

Background: Breast cancer is one of the deadly tumors in women, and its incidence continues to increase. This study aimed to identify novel therapeutic molecules using RNA sequencing (RNA-seq) data of breast cancer from our hospital. Methods: 30 pairs of human breast cancer tissue and matched normal tissue were collected and RNA sequenced in our hospital. Differentially expressed genes (DEGs) were calculated with raw data by the R package "edgeR", and functionally annotated using R package "clusterProfiler". Tumor-infiltrating immune cells (TIICs) were estimated using a website tool TIMER 2.0. Effects of key genes on therapeutic efficacy were analyzed using RNA-seq data and drug sensitivity data from two databases: the Cancer Cell Line Encyclopedia (CCLE) and the Cancer Therapeutics Response Portal (CTRP). Results: There were 2,953 DEGs between cancerous and matched normal tissue, as well as 975 DEGs between primary breast cancer and metastatic breast cancer. These genes were primarily enriched in PI3K-Akt signaling pathway, calcium signaling pathway, cAMP signaling pathway, and cell cycle. Notably, CD8⁺ T cell, M0 macrophage, M1 macrophage, regulatory T cell and follicular helper T cell were significantly elevated in cancerous tissue as compared with matched normal tissue. Eventually, we found five genes (GALNTL5, MLIP, HMCN2, LRRN4CL, and DUOX2) were markedly corelated with CD8⁺ T cell infiltration and cytotoxicity, and associated with therapeutic response. Conclusion: We found five key genes associated with tumor progression, CD8⁺ T cell and therapeutic efficacy. The findings would provide potential molecular targets for the treatment of breast cancer.

DUOX1 in mammalian disease pathophysiology

Dual oxidase 1 (DUOX1) is a member of the protein family of nicotinamide adenine dinucleotide phosphate (NADPH) oxidases. DUOX1 has several normal physiological, immunological, and biochemical functions in different parts of the body. Dysregulated oxidative metabolism interferes with various disease pathologies and numerous therapeutic options are based on targeting cellular redox pathways. DUOX1 forms an important enzymatic source of biological oxidants, and DUOX1 expression is frequently dysregulated in various diseases. While this review shortly addresses the biochemical and cellular properties and proposed physiological roles of DUOX1, its main purpose is to summarize the current knowledge with respect to the potential role of DUOX1 enzyme in disease pathology, especially in mammalian organisms. Although DUOX1 is normally prominently expressed in epithelial lineages, it is frequently silenced in epithelial-derived cancers by epigenetic mechanisms. While an abundance of information is available on DUOX1 transcription in different diseases, an increasing number of mechanistic studies indicate a causative relationship between DUOX1 function and disease pathophysiology. Additionally, specific functions of the DUOX1 maturation factor, DUOXA1, will also be addressed. Lastly, urgent and outstanding questions on the field of DUOX1 will be discussed that could provide valuable new diagnostic tools and novel therapeutic options.

Inhibiting the Activity of NADPH Oxidase in Cancer

Significance: The primary function of NADPH oxidases (NOX1-5 and dual oxidases DUOX1/2) is to produce reactive oxygen species (ROS). If inadequately regulated, NOX-associated ROS can promote oxidative stress, aberrant signaling, and genomic instability. Correspondingly, NOX isoforms are known to be overexpressed in multiple malignancies, thus constituting potential therapeutic targets in cancer. Recent Advances: Multiple genetic studies aimed at suppressing the expression of NOX proteins in cellular and animal models of cancer have provided support for the notion that NOXs play a pro-tumorigenic role. Further, large drug screens and rational design efforts have yielded inhibitor compounds, such as the diphenylene iodonium (DPI) analog series developed by our group, with increased selectivity and potency over "first generation" NOX inhibitors such as apocynin and DPI. Critical Issues: The precise role of NOX enzymes in tumor biology remains poorly defined. The tumorigenic properties of NOXs vary with cancer type, and precise tools, such as selective inhibitors, are needed to deconvolute NOX contribution to cancer development. Most NOX inhibitors developed to date are unspecific, and/or their mechanistic and pharmacological characteristics are not well defined. A lack of high-resolution crystal structures for NOX functional domains has hindered the development of potent and selective inhibitors. Future Directions: In-depth studies of NOX interactions with the tumor microenvironment (e.g., cytokines, cell-surface antigens) will help identify new approaches for NOX inhibition in cancer.

The role of dual oxidases in physiology and cancer

NOX/DUOX enzymes are transmembrane proteins that carry electrons through biological membranes generating reactive oxygen species. The NOX family is composed of seven members, which are NOX1 to NOX5 and DUOX1 and 2. DUOX enzymes were initially called thyroid oxidases, based on their high expression level in the thyroid tissue. However, DUOX expression has been documented in several extrathyroid tissues, mostly at the apical membrane of the salivary glands, the airways, and the intestinal tract, revealing additional cellular functions associated with DUOX-related H2O2 generation. In this review, we will briefly summarize the current knowledge regarding DUOX structure and physiological functions, as well as their possible role in cancer biology.

Isoquercitrin promotes peripheral nerve regeneration through inhibiting oxidative stress following sciatic crush injury in mice

Background

Oxidative stress has been recognized to play a crucial role in the pathogenesis of peripheral nerve injury. Isoquercitrin (quercetin-3-glucoside) is a flavonoid that exhibited many biological activities, including anti-oxidative effect. However, it is unclear whether isoquercitrin has protective effects on peripheral nerve injury.

Methods

Mice treated by isoquercitrin were used as a case group, and mice injected with saline was the control group. Sciatic behavioral function was assessed using SFI and CMAPs were measured by electrophysiology. Schwann cells proliferation and migration were tested using EdU staining and Transwell migration chambers respectively. The expression of oxidative stress related factors were detected by qRT-PCR and Western blotting.

Results

In present study, our results demonstrated that isoquercitrin (20 mg/kg/day) treatment achieved significantly higher SFI and higher amplitude of CMAP, promoted the nerve regeneration and remyelination, increased the production of GAP43, NF200, MAG and PMP22, alleviated target muscle atrophy and autophagy, and suppressed the expression of ATG7, PINK1 and Beclin1 in soleus muscles after sciatic nerve crush. In vitro studies found that isoquercitrin promoted the axonal regeneration of DRGs neurons, the proliferation and migration of Schwann cells, and the expression of proliferating cell nuclear antigen (PCNA) in Schwann cells. The administration of isoquercitrin at 40 and 320 µM showed a dose dependent, and high doses of isoquercitrin (160 and 320 µM) showed better performance in promoting axonal regeneration of DRGs neurons, and the proliferation and migration of Schwann cells than low dose of isoquercitrin (40 µM). Furthermore, isoquercitrin significantly inhibited oxidative stress through reducing the production of Nox4 and Duox1, and promoting the expression of Nrf2 and SOD2 in soleus muscles after sciatic nerve crush.

Conclusions

Isoquercitrin may promote motor functional recovery and nerve regeneration following peripheral nerve injury though inhibition of oxidative stress, which highlighted the therapeutic values of isoquercitrin as a neuroprotective drug for peripheral nerve repair applications.

Two-Stage Classification with SIS Using a New Filter Ranking Method in High Throughput Data

Over the last decade, high dimensional data have been popularly paid attention to in bioinformatics. These data increase the likelihood of detecting the most promising novel information. However, there are limitations of high-performance computing and overfitting issues. To overcome the issues, alternative strategies need to be explored for the detection of true important features. A two-stage approach, filtering and variable selection steps, has been receiving attention. Filtering methods are divided into two categories of individual ranking and feature subset selection methods. Both have issues with the lack of consideration for joint correlation among features and computing time of an NP-hard problem. Therefore, we proposed a new filter ranking method (PF) using the elastic net penalty with sure independence screening (SIS) based on resampling technique to overcome these issues. We demonstrated that SIS-LASSO, SIS-MCP, and SIS-SCAD with the proposed filtering method achieved superior performance of not only accuracy, AUROC, and geometric mean but also true positive detection compared to those with the marginal maximum likelihood ranking method (MMLR) through extensive simulation studies. In addition, we applied it in a real application of colon and lung cancer gene expression data to investigate the classification performance and power of detecting true genes associated with colon and lung cancer.