Caspase-related apoptosis genes in gliomas by RNA-seq and bioinformatics analysis

Expanding the Functions of KHSRP Protein: Insights into DNA G-Quadruplex Binding

KHSRP (KH-type splicing regulatory protein) is a multifunctional nucleic acid-binding protein that regulates various cellular processes, with critical roles in controlling gene expression. G-quadruplexes (G4s) are noncanonical nucleic acid structures involved in essential cellular activities, including gene expression, and are recognized as potential therapeutic targets in cancer. The biological functions of G4s are mediated by proteins making their formation highly dynamic within cells. Therefore, the recognition of G4s by specific proteins is crucial for modulating physiological and pathological pathways. Given the growing interest in DNA G4s, a deeper understanding of the proteins that interact with them and their molecular recognition is imperative. This study demonstrates that KHSRP binds to these DNA structures. Biophysical analyses provide insights into the thermodynamics, kinetics, and structural aspects of these interactions, showing that G4 structural variability significantly influences KHSRP binding, in which the KH3 protein domain plays a key role. Validation of these interactions in cancer cells further highlights their biological relevance. Notably, the G4 ligand pyridostatin affects KHSRP/G4 interactions both in vitro and in cells, suggesting that small molecules can modulate this molecular recognition. These findings underscore KHSRP's potential role in regulating cellular mechanisms through binding to G4-forming DNA, positioning it as a possible therapeutic target in cancer.

Exploring a novel four-gene system as a diagnostic and prognostic biomarker for triple-negative breast cancer, using clinical variables

Triple-negative breast cancer (TNBC) is a subtype of breast cancer with a poor prognosis. This research aims to find real hub genes for prognostic biomarkers of TNBC therapy. The GEO datasets GSE27447 and GSE233242 were analyzed using R package limma to explore DEGs. The PPI was generated using the STRING database. Cytoscape software plug-ins were used to screen the hub genes. Using the DAVID database, GO functional enrichment and KEGG pathway enrichment analysis were performed. Different online expression databases were employed to investigate the functions of real hub genes in tumor driving, diagnosis, and prognosis in TNBC patients with various clinicopathologic characteristics. A total of one hundred DEGs were identified between both datasets. The seven hub genes were identified after the topological parameter analysis of the PPI network. The KEGG pathway and GO analysis suggest that four genes (PSMB1, PSMC1, PSMF1, and PSMD8) are highly enriched in proteasome and were finally considered as real hub genes. Additionally, the expression analysis demonstrated that hub genes were notably up-regulated in TNBC patients compared to controls. Furthermore, correlational analyses revealed the positive and negative correlations among the expression of the real hub genes and various ancillary data, including tumor purity, promoter methylation status, overall survival (OS), genetic alterations, infiltration of CD8+ T and CD4+ immune cells, and a few more, across TNBC samples. Finally, our analysis identified a couple of significant chemotherapeutic drugs, miRNAs and transcription factors (TFS) with intriguing curative potential. In conclusion, we identified four real hub genes as novel biomarkers to overcome heterogenetic-particular challenges in diagnosis, prognosis, and therapy for TNBC patients.

Strophanthidin Induces Apoptosis of Human Lung Adenocarcinoma Cells by Promoting TRAIL-DR5 Signaling

Strophanthidin (SPTD), one of the cardiac glycosides, is refined from traditional Chinese medicines such as Semen Lepidii and Antiaris toxicaria, and was initially used for the treatment of heart failure disease in clinic. Recently, SPTD has been shown to be a potential anticancer agent, but the underlying mechanism of action is poorly understood. Herein, we explored the molecular mechanism by which SPTD exerts anticancer effects in A549 human lung adenocarcinoma cells by means of mass spectrometry-based quantitative proteomics in combination with bioinformatics analysis. We revealed that SPTD promoted the expression of tumor necrosis factor (TNF)-related apoptosis-inducing ligand receptor 2 (TRAIL-R2, or DR5) in A549 cells to activate caspase 3/6/8, in particular caspase 3. Consequently, the activated caspases elevated the expression level of apoptotic chromatin condensation inducer in the nucleus (ACIN1) and prelamin-A/C (LMNA), ultimately inducing apoptosis via cooperation with the SPTD-induced overexpressed barrier-to-autointegration factor 1 (Banf1). Moreover, the SPTD-induced DEPs interacted with each other to downregulate the p38 MAPK/ERK signaling, contributing to the SPTD inhibition of the growth of A549 cells. Additionally, the downregulation of collagen COL1A5 by SPTD was another anticancer benefit of SPTD through the modulation of the cell microenvironment.

Identification of potential target genes of breast cancer in response to Chidamide treatment

Chidamide, a new chemically structured HDACi-like drug, has been shown to inhibit breast cancer, but its specific mechanism has not been fully elucidated. In this paper, we selected ER-positive breast cancer MCF-7 cells and used RNA-seq technique to analyze the gene expression differences of Chidamide-treated breast cancer cells to identify the drug targets of Chidamide's anti-breast cancer effect and to lay the foundation for the development of new drugs for breast cancer treatment. The results showed that the MCF-7 CHID group expressed 320 up-regulated genes and 222 down-regulated genes compared to the control group; Gene Ontology functional enrichment analysis showed that most genes were enriched to biological processes. Subsequently, 10 hub genes for Chidamide treatment of breast cancer were identified based on high scores using CytoHubba, a plug-in for Cytoscape: TP53, JUN, CAD, ACLY, IL-6, peroxisome proliferator-activated receptor gamma, THBS1, CXCL8, IMPDH2, and YARS. Finally, a combination of the Gene Expression Profiling Interactive Analysis database and Kaplan Meier mapper to compare the expression and survival analysis of these 10 hub genes, TP53, ACLY, PPARG, and JUN were found to be potential candidate genes significantly associated with Chidamide for breast cancer treatment. Among them, TP53 may be a potential target gene for Chidamide to overcome multi-drug resistance in breast cancer. Therefore, we identified four genes central to the treatment of breast cancer with Chidamide by bioinformatics analysis, and clarified that TP53 may be a potential target gene for Chidamide to overcome multi-drug resistance in breast cancer. This study lays a solid experimental and theoretical foundation for the treatment of breast cancer at the molecular level with Chidamide and for the combination of Chidamide.

Insights into H2O2-induced signaling in Jurkat cells from analysis of gene expression

Hydrogen peroxide (H₂O₂) is a ubiquitous oxidant produced in a regulated manner by various enzymes in mammalian cells. H₂O₂ reversibly oxidizes thiol groups of cysteine residues to mediate intracellular signaling. While examples of H₂O_2-dependent signaling have been reported, the exact molecular mechanism(s) of signaling and the pathways affected are not well understood. Here, the transcriptomic response of Jurkat T cells to H₂O₂ was investigated to determine global effects on gene expression. With a low H₂O₂ concentration (10 µM) that did not induce an oxidative stress response or cell death, extensive changes in gene expression occurred after 4 h (6803 differentially expressed genes). Of the genes with a greater then 2-fold change in expression, 85% were upregulated suggesting that in a physiological setting H₂O₂ predominantly activates gene expression. Pathway analysis identified gene expression signatures associated with FOXO and NTRK signaling. These signatures were associated with an overlapping set of transcriptional regulators. Overall, our results provide a snapshot of gene expression changes in response to H₂O_2, which, along with further studies, will lead to new insights into the specific pathways that are activated in response to endogenous production of H₂O₂, and the molecular mechanisms of H₂O₂ signaling.

The Role of KH-Type Splicing Regulatory Protein (KSRP) for Immune Functions and Tumorigenesis

Post-transcriptional control of gene expression is one important mechanism that enables stringent and rapid modulation of cytokine, chemokines or growth factors expression, all relevant for immune or tumor cell function and communication. The RNA-binding protein KH-type splicing regulatory protein (KSRP) controls the mRNA stability of according genes by initiation of mRNA decay and inhibition of translation, and by enhancing the maturation of microRNAs. Therefore, KSRP plays a pivotal role in immune cell function and tumor progression. In this review, we summarize the current knowledge about KSRP with regard to the regulation of immunologically relevant targets, and the functional role of KSRP on immune responses and tumorigenesis. KSRP is involved in the control of myeloid hematopoiesis. Further, KSRP-mediated mRNA decay of pro-inflammatory factors is necessary to keep immune homeostasis. In case of infection, functional impairment of KSRP is important for the induction of robust immune responses. In this regard, KSRP seems to primarily dampen T helper cell 2 immune responses. In cancer, KSRP has often been associated with tumor growth and metastasis. In summary, aside of initiation of mRNA decay, the KSRP-mediated regulation of microRNA maturation seems to be especially important for its diverse biological functions, which warrants further in-depth examination.

Prognoses and genomic analyses of proteasome 26S subunit, ATPase (PSMC) family genes in clinical breast cancer

Breast cancer is a complex disease, and several processes are involved in its development. Therefore, potential therapeutic targets need to be discovered for these patients. Proteasome 26S subunit, ATPase gene (PSMC) family members are well reported to be involved in protein degradation. However, their roles in breast cancer are still unknown and need to be comprehensively researched. Leveraging publicly available databases, such as cBioPortal and Oncomine, for high-throughput transcriptomic profiling to provide evidence-based targets for breast cancer is a rapid and robust approach. By integrating the aforementioned databases with the Kaplan–Meier plotter database, we investigated potential roles of six PSMC family members in breast cancer at the messenger RNA level and their correlations with patient survival. The present findings showed significantly higher expression profiles of PSMC2, PSMC3, PSMC4, PSMC5, and PSMC6 in breast cancer compared to normal breast tissues. Besides, positive correlations were also revealed between PSMC family genes and ubiquinone metabolism, cell cycle, and cytoskeletal remodeling. Meanwhile, we discovered that high levels of PSMC1, PSMC3, PSMC4, PSMC5, and PSMC6 transcripts were positively correlated with poor survival, which likely shows their importance in breast cancer development. Collectively, PSMC family members have the potential to be novel and essential prognostic biomarkers for breast cancer development.