Identification of CDCA8, DSN1 and BIRC5 in Regulating Cell Cycle and Apoptosis in Osteosarcoma Using Bioinformatics and Cell Biology

DSN1 may predict poor prognosis of lower-grade glioma patients and be a potential target for immunotherapy

DSN1 has been previously found to be positively correlated with various cancers. However, the effect of DSN1 or its methylation on the prognosis, molecular characteristics, and immune cell infiltration of low-grade glioma (LGG) has not yet been studied. We obtained 1046 LGG samples from the The Cancer Genome Atlas, The Chinese Glioma Genome Atlas (CGGA) microarray, and CGGA RNA-Seq databases. Bioinformatic methods (gene set enrichment analysis (GSEA), chi-square test, multivariate), and laboratory validation were used to investigate DSN1 in LGG. The expression levels of DSN1 mRNA and protein in LGG were substantially higher than those in normal brain tissue, and their expression was negatively regulated by methylation. The survival time of patients with low expression of DSN1 and cg12601032 hypermethylation was considerably prolonged. DSN1 was a risk factor, and of good diagnostic and prognostic value for LGG. Importantly, the expression of DSN1 is related to many types of tumor-infiltrating immune cells and has a positive correlation with PDL1. DSN1 promoted the activation of multiple cancer-related pathways, such as the cell cycle. Additionally, knockdown of DSN1 substantially inhibited the proliferation and invasion of LGG cells. To the best of our knowledge, this study is the first comprehensive analysis of the mechanism of DSN1 leading to poor prognosis of LGG, which provides a new perspective for revealing the pathogenesis of LGG. DSN1 or its methylation has diagnostic value for the prognosis of glioma, and may become a new biological target of anti-tumor immunotherapy.

DSN1 Interaction With Centromere-Associated Proteins Promotes Chromosomal Instability in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the most prevalent type of liver cancer. Dosage suppressor of NNF1 (DSN1), a component of the MIS12 kinetochore complex, encodes a kinetochore protein crucial for proper mitotic assembly. The role of DSN1 in HCC remains to be elucidated. In this study, we utilized The Cancer Genome Atlas, the Hepatocellular carcinoma Cell Database, and other databases to analyze DSN1 expression and prognosis in samples from patients with HCC. We investigated the signaling pathways regulated by DSN1 and their implications in HCC. Additionally, we engineered siRNAsiRNA/shRNA/shRNA and overexpression vectors for DSN1 and assessed the specific mechanisms of regulatory pathways of DSN1 in hepatoma cell lines and subcutaneous tumor xenograft model. Our findings revealed that DSN1 expression was significantly upregulated in patients with HCC, correlating with decreased survival rates. Elevated DSN1 expression led to the overproduction of cell cycle-related proteins through direct interaction with Centromere Protein T. This interaction contributes to chromosomal instability in patients with HCC, resulting in an aberrant cell cycle and fostering the development and progression of HCC. Increased DSN1 expression is pivotal in HCC initiation and progression. Investigating DSN1 offers valuable insights into the pathogenesis, treatment, and prevention of HCC.

TMED3 promotes the development of malignant melanoma by targeting CDCA8 and regulating PI3K/Akt pathway

BACKGROUND

Transmembrane emp24 domain containing (TMED) proteins are known to play pivotal roles in normal development, but have been reported to be implicated in pancreatic disease, immune system disorders, and cancers. As far as TMED3 is concerned, its roles in cancers are controversial. However, evidence describing TMED3 in the context of malignant melanoma (MM) is scarce.

RESULTS

In this study, we characterized the functional significance of TMED3 in MM and identified TMED3 as a tumor-promoting factor in MM development. Depletion of TMED3 arrested the development of MM in vitro and in vivo. Mechanistically, we found that TMED3 could interact with Cell division cycle associated 8 (CDCA8). Knocking down CDCA8 suppressed cell events associated with MM development. On the contrary, elevating CDCA8 augmented cell viability and motility and even reversed the inhibitory effects of TMED3 knockdown on MM development. On the other hand, we found that the levels of P-Akt and P-PI3K were decreased in response to TMED3 downregulation, which was partially abolished following SC79 treatment. Thus, our suspicion was that TMED3 exacerbates MM progression via PI3K/Akt pathway. More notably, previously decreased P-Akt and P-PI3K in TMED3-depleted cells were rescued after overexpressing CDCA8. Also, previously impaired cell events due to CDCA8 depletion were ameliorated after SC79 addition, implying that TMED3 regulates PI3K-AKT pathway via CDCA8, thereby promoting MM development.

CONCLUSIONS

Collectively, this study established the link between TMED3 and MM, and provides a potential therapeutic intervention for patients with MM harboring abundant TMED3.

Identification of miR-3182 and miR-3143 target genes involved in the cell cycle as a novel approach in TNBC treatment: A systems biology approach

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer with a poor prognosis, lacking therapeutic targets. miRNAs play crucial roles in TNBC through regulating various mechanisms, including cellular growth and proliferation. This study aims to identify critical target genes of two novel miRNAs (miR-3143 and miR-3182) involved in the cell cycle of TNBC as possible therapeutic targets and investigates their regulatory and therapeutic roles through a systems biology approach and in vitro experiment. Datasets related to the TNBC cell line (MDA-MB-231) were screened and retrieved, and Gene regulatory networks were constructed. Significant regulatory motifs were detected and analyzed using the FANMOD and Cytoscape analyzer, and the clusters and seeds were identified using the MCODE. Functional enrichment analysis was also performed using DAVID and STRING. The most critical genes were determined using the analysis of GRN motifs and PPI clusters. The essential genes involved in the cell cycle were selected and verified using the bc-GenExMiner v4.7. We overexpressed miR-3143 and miR-3182 in the MDA-MB-231 cell line using human umbilical cord mesenchymal stem cell (HUCMSC)-miRNA loaded exosomes, and the expression of the critical target genes was investigated using RT-qPCR. We identified eight critical genes as potential therapeutic targets. Their expression decreased by overexpression of miR-3143 and miR-3182 in RT-qPCR. The identified critical genes have probably significant roles in the pathogenesis of TNBC through the cell cycle. We suggest that the overexpression of miR-3143 and miR-3182 could be a new therapeutic candidate in TNBC and is worth more investigation.

mRNA, lncRNA, and circRNA expression profiles in a new aortic dissection murine model induced by hypoxia and Ang II

Background and aims

Aortic dissection (AD) is a cardiovascular emergency with degeneration of the aortic media. Mounting evidence indicates obstructive sleep apnea (OSA) as an independent risk factor for AD development with unknown mechanisms. This study aims to establish a stable murine model of OSA-related AD (OSA-AD) and uncover the potential changes in gene transcripts in OSA-AD.

Materials and methods

ApoE^–/– mice were exposed to the chronic intermittent hypoxia (CIH) system combined with Ang II administration to establish the OSA-AD model. Pathological staining was performed to exhibit the physiological structure of the mouse aorta. The SBC mouse ceRNA microarray was used to identify significantly differentially expressed (DE) mRNAs, DE long-non-coding RNAs (DElncRNAs), and DE circular RNAs (DEcircRNAs) in OSA-AD tissues. Subsequently, bioinformatics analysis, including Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genome (KEGG), and protein–protein interaction (PPI) analyses, were performed to evaluate the function of the significantly differentially expressed transcripts (DETs). The hub genes were confirmed using quantitative real-time polymerase chain reaction (qRT-PCR).

Results

ApoE^–/– mice exposed to CIH and Ang II showed a high ratio of aortic accident (73.33%) and significant aortic diameter dilatation (1.96 ± 0.175 mm). A total of 1,742 mRNAs, 2,625 lncRNAs, and 537 circRNAs were identified as DETs (LogFC ≥ 1.5 or ≤ –1.5, P < 0.05). GO and KEGG analyses demonstrated that the differentially expressed mRNAs (DEmRNAs) were most enriched in cell proliferation, migration, apoptosis, inflammation, and hypoxia-related terms, which are closely related to aortic structural homeostasis. The PPI network contained 609 nodes and 934 connections, the hub genes were highlighted with the CytoHubba plugin and confirmed by qRT-PCR in AD tissues. KEGG pathway analysis revealed that the cis-regulated genes of DElncRNAs and circRNAs-host genes were enriched in aortic structural homeostasis-related pathways.

Conclusion

Our findings help establish a de novo OSA-AD animal model using ApoE^–/– mice. Many DEmRNAs, DElncRNAs, and DEcircRNAs were screened for the first time in OSA-AD tissues. Our findings provide useful bioinformatics data for understanding the molecular mechanism of OSA-AD and developing potential therapeutic strategies for OSA-AD.

SRSF9 promotes colorectal cancer progression via stabilizing DSN1 mRNA in an m6A-related manner

Background

Serine/arginine-rich splicing factor 9 (SRSF9) is a classical RNA-binding protein that is essential for regulating gene expression programs through its interaction with target RNA. Whether SRSF9 plays an essential role in colorectal cancer (CRC) progression and can serve as a therapeutic target is largely unknown. Here, we highlight new findings on the role of SRSF9 in CRC progression and elucidate the underlying mechanism.

Methods

CRC cell lines and clinical tissue samples were used. qRT-PCR, Western blotting, immunohistochemistry (IHC), gain- and loss-of-function assays, animal xenograft model studies, bioinformatic analysis, methylated single-stranded RNA affinity assays, gene-specific m6A quantitative qRT-PCR, dual-luciferase reporter assays and RNA stability assays were performed in this study.

Results

The expression level of SRSF9 was higher in CRC cell lines than that in an immortal human intestinal epithelial cell line. Overexpression of SRSF9 was positively associated with lymph node metastasis and Dukes stage. Functionally, SRSF9 promoted cell proliferation, migration and invasion in vitro and xenograft growth. The results of bioinformatic analysis indicated that DSN1 was the downstream target of SRSF9. In CRC cells and clinical tissue samples, the expression of SRSF9 was positively associated with the expression of DSN1. Knockdown of DSN1 partially inhibited the SRSF9-induced phenotype in CRC cells. Mechanistically, we further found that SRSF9 is an m6A-binding protein and that m6A modifications were enriched in DSN1 mRNA in CRC cells. Two m6A modification sites (chr20:36773619–36773620 and chr20:36773645–chr20:36773646) in the SRSF9-binding region (chr20:36773597–36773736) of DSN1 mRNA were identified. SRSF9 binds to DSN1 in an m6A motif- and dose-dependent manner. SRSF9 modulates the expression of DSN1 in CRC cells. Such expression regulation was largely impaired upon methyltransferase METTL3 knockdown. Moreover, knockdown of SRSF9 accelerated DSN1 mRNA turnover, while overexpression of SRSF9 stabilized DSN1 mRNA in CRC cells. Such stabilizing was also weakened upon METTL3 knockdown.

Conclusion

Overexpression of SRSF9 was associated with lymph node metastasis and Dukes stage in CRC. Knockdown of DSN1 eliminated the effects by SRSF9 overexpression in CRC. Our results indicated that SRSF9 functions as an m6A-binding protein (termed “reader”) by enhancing the stability of DSN1 mRNA in m6A-related manner. Our study is the first to report that SRSF9-mediated m6A recognition has a crucial role in CRC progression, and highlights SRSF9 as a potential therapeutic target for CRC management.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-022-03399-3.

Anticancer Action of Xiaoxianxiong Tang in Non-Small Cell Lung Cancer by Pharmacological Analysis and Experimental Validation

Xiaoxianxiong Tang (XXXT) is a well-known traditional Chinese medicine formula. Evidence is emerging supporting the benefits of XXXT in ameliorating therapy for non-small cell lung cancer (NSCLC). The purpose of this study aimed to explore the effects and mechanisms of XXXT through network pharmacological analysis and biological validation. TCMSP database was used to identify potentially active compounds in XXXT with absorption, distribution, metabolism, excretion screening, and their potential targets. The disease targets related to NSCLC were predicted by searching for Therapeutic Target database, GeneCards database, DrugBank database, and DisGeNET database. Of the 4385 NSCLC-related targets, 156 targets were also the targets of compounds present in XXXT. Subsequently, GO function and KEGG pathway enrichment and PPI network analyses revealed that, of the 95 targets and 20 pathways influenced by 20 ingredients in XXXT, 20 targets were associated with patient survival, and XXXT could exert an inhibitory action on the PI3K-AKT signaling pathway. Moreover, XXXT restrained the proliferation of A549 and H460 cells in a concentration-dependent manner and suppressed the mRNA and protein levels of key targets CCNA2, FOSL2, and BIRC5 closely linked to the PI3K-AKT pathway. Hence, XXXT has the potential to improve therapy for NSCLC by targeting the PI3K-AKT signaling pathway.

DSN1 is a prognostic biomarker and correlated with clinical characterize in breast cancer

DSN1 affects cell cycle progression and is associated with clinical-pathological features in colorectal and hepatocellular carcinomas. However, the biological function of DSN1 in breast cancer is still indistinct. In this study, we comprehensively analyzed the correlation between DSN1 expression in different molecular subtypes or stages of breast cancer and investigated the prognostic value of DSN1 in databases such as Oncomine, Cancer Cell Line Encyclopedia, UALCAN, Human Protein Atlas, Kaplan-Meier Plotter, OncoLnc, GEPIA. Moreover, we investigated the correlation of DSN1 with tumor-infiltrating immune cells in the different tumor microenvironments via Tumor Immune Estimation Resource database and explore DSN1 co-expression networks in breast cancer via LinkedOmics analysis, NetworkAnalyst database analysis. Finally, we also performed our immunohistochemical experiments to explore the expression of DSN1 in different stages or subtypes of breast cancer. The findings in this article shed light on the essential role of DSN1 in breast cancers as well as suggested that the upregulation of DSN1 expression was strongly associated with poor prognosis and decreased survival in breast cancer, and there were significant differences in its expression in different pathological subtypes and stages of breast cancer.