DDX19A Promotes Metastasis of Cervical Squamous Cell Carcinoma by Inducing NOX1-Mediated ROS Production

A Comprehensive Pan-Cancer Analysis of Cytochrome C Oxidase Assembly Factor 1 (COA1) Reveals Instrumental Role of Mitochondrial Protein Assembly in Cancer that Modulates Disease Progression and Prognostic Outcome

Cytochrome c oxidase assembly factor 1 (COA1), a mitochondrial respiratory chain complex assembly factor protein of inner mitochondrial membrane (IMM), is involved in translating many mitochondrial components and assembling nuclear-encoded components within mitochondria. Given the lack of extensive research on COA1 in cancer, this study undertakes a comprehensive pan-cancer analysis of COA1, which is overexpressed across various cancer types, shedding light on its multifaceted role in tumorigenesis, prognosis, and tumor microenvironment (TME) modulation. Leveraging bioinformatics tools and public databases, we elucidated its potential as a diagnostic cancer biomarker as well as a target for novel anti-cancer therapeutics. Gene expression analysis using "TIMER2.0", "UALCAN" and "GEPIA2" platforms, supported by protein expression data, revealed a significant correlation between COA1 upregulation and poor prognosis in Kaplan-Meir analysis, underscoring its clinical relevance. Additionally, genetic mutation analysis of COA1 with the help of "cBioPortal" warrants further exploration into its functional significance. Moreover, our investigation of the tumor microenvironment unveiled the interplay of COA1 with fibroblast and T cell infiltration implicating the role of COA1 in the tumor immune microenvironment. Furthermore, COA1-related gene enrichment study in "GeneMANIA" and pathway cross-talk analysis with Gene Ontology (GO) gene sets established comprehensive clarifications about the molecular pathways and protein networks associated with COA1 deregulation. Overall, this study lays a sturdy foundation to support future research endeavors targeting COA1, unraveling the molecular mechanisms underlying COA1 deregulation, and exploring its therapeutic potential in cancer.

DDX19A promotes gastric cancer cell proliferation and migration by activating the PI3K/AKT pathway

BACKGROUND

DEAD-box RNA helicase 19 A (DDX19A) is overexpressed in cervical squamous cell carcinoma. However, its role in gastric cancer remains unclear. The present study aimed to explore the role and underlying mechanism of DDX19A in the development of gastric cancer.

METHODS

The expression of DDX19A in gastric cancer and paracancerous tissues was evaluated through quantitative polymerase chain reaction, western blotting, and immunohistochemical staining. The biological functions of DDX19A in gastric cancer were determined using CCK8, plate colony-forming, and Transwell migration assays. The specific mechanism of DDX19A in gastric cancer cells was studied using western blotting, RNA-binding protein immunoprecipitation, mRNA half-life detection, and nuclear and cytoplasmic RNA isolation.

RESULTS

DDX19A was highly expressed in gastric cancer and positively associated with malignant clinicopathological features and poor prognosis. Additionally, DDX19A promoted gastric cancer cell proliferation, migration, and epithelial-mesenchymal transition phenotypes. Mechanistically, DDX19A activated the PI3K/AKT pathway by upregulating phosphatidylinositol-3-kinase (PIK3CA) expression. Furthermore, DDX19A interacted with PIK3CA mRNA, stabilized it, and facilitated its export from the nucleus.

CONCLUSIONS

Our study reveals a novel mechanism whereby DDX19A promotes the proliferation and migration of gastric cancer cells by enhancing the stability and nuclear export of PIK3CA mRNA, thereby activating the PI3K/AKT pathway.

Exosomal NOX1 promotes tumor-associated macrophage M2 polarization-mediated cancer progression by stimulating ROS production in cervical cancer: a preliminary study

BACKGROUND

Cervical cancer the fourth most frequently diagnosed cancer and the fourth leading cause of cancer death in women, with an estimated 604,000 new cases and 342,000 deaths worldwide in 2020 for high rates of recurrence and metastasis. Identification of novel targets could aid in the prediction and treatment of cervical cancer. NADPH oxidase 1 (NOX1) gene-mediated production of reactive oxygen species (ROS) could induce migration and invasion of cervical cancer cells. Tumor-associated macrophages (TAMs) play important roles in cervical cancer. Tumor cell-derived exosomes mediate signal transduction between the tumor and tumor microenvironment. Elucidation of the mechanisms of NOX1-carrying exosomes involved in the regulation of TAMs may provide valuable insights into the progression of cervical cancer.

METHODS

Uniformly standardized mRNA data of pan-carcinoma from the UCSC database were downloaded. Expression of NOX1 in tumor and adjacent normal tissues for each tumor type was calculated using R language software and significant differences were analyzed. SNP data set were downloaded for all TCGA samples processed using MuTect2 software from GDC. Cell experiment and animal tumor formation experiment were used to evaluate whether exosomal NOX1 stimulating ROS production to promote M2 polarization of TAM in cervical cancer.

RESULTS

NOX1 is highly expressed with a low mutational frequency in pan-carcinoma. Upregulation of NOX1 may be associated with infiltration of M2-type macrophages in cervical cancer tissues, and NOX1 promotes malignant features of cervical cancer cells by stimulating ROS production. Exosomal NOX1 promotes M2 polarization of by stimulating ROS production. Exosomal NOX1 enhances progression of cervical cancer and M2 polarization in vivo by stimulating ROS production.

CONCLUSION

Exosomal NOX1 promotes TAM M2 polarization-mediated cancer progression through stimulating ROS production in cervical cancer.

Silencing of let-7b-5p inhibits ovarian cancer cell proliferation and stemness characteristics by Asp-Glu-Ala-Asp-box helicase 19A

The emergence and recurrence of ovarian cancer are associated with ovarian cancer stem cells. For cancer treatment, gene delivery of microbubbles (MB)-mediated microRNA (miRNA) is considered as a promising approach. In this study, our aim is to investigate the effects of MB-mediated let-7b-5p inhibitor on the proliferation and stemness characteristics of ovarian cancer (OVCA) cells. Let-7b-5p inhibitor mediated by MB was prepared (termed MB-let-7b-5p inhibitor), and the effects of MB-let-7b-5p inhibitor and let-7b-5p inhibitor on OVCA cell viability, proliferation and stemness characteristics were investigated. We found that MB-let-7b-5p inhibitor presented a higher transfection efficiency than let-7b-5p inhibitor alone. The inhibitory effect of MB-let-7b-5p inhibitor on OVCA cells was more significant than let-7b-5p inhibitor. Let-7b-5p targeted DEAD (Asp-Glu-Ala-Asp)-box helicase 19A (DDX19A), which was downregulated in OVCA cells. The downregulation of DDX19A reversed the inhibitory effects of MB-let-7b-5p inhibitor on OVCA cells. To sum up, we found that MB-let-7b-5p suppressed OVCA cell malignant behaviors by targeting DDX19A.