SKA1 promotes malignant phenotype and progression of glioma via multiple signaling pathways

Integrated analysis of SKA1-related ceRNA network and SKA1 immunoassays in HCC: A study based on bioinformatic

Hepatocellular carcinoma (HCC) poses a global health challenge. Effective biomarkers are required for early diagnosis to improve survival rates of patients with HCC. Spindle and kinetochore-associated complex subunits 1 (SKA1) is essential for proper chromosome segregation in the mitotic cell cycle. Previous studies have shown that overexpression of SKA1 is associated with a poor prognosis in various cancers. The expression, prognostic value, and clinical functions of SKA1 in HCC were evaluated with several bioinformatics web portals. Additionally, we identified target long non-coding RNAs (lncRNAs) and microRNAs by analyzing messenger RNA (mRNA)-miRNA and miRNA-lncRNA interaction data and elucidated the potential competing endogenous RNA (ceRNA) mechanism associated with SKA1. High SKA1 expression was associated with poor prognosis in patients with HCC. Furthermore, multivariate Cox regression analysis revealed that SKA1 expression was an independent prognostic factor for HCC. GO and KEGG analyses showed that SKA1 is related to the cell cycle checkpoints, DNA replication and repair, Rho GTPases signaling, mitotic prometaphase, and kinesins. Gene set enrichment analysis revealed that high levels of SKA1 are associated with cancer-promoting pathways. DNA methylation of SKA1 in HCC tissues was lower than that in normal tissues. Ultimately, the following 9 potential ceRNA-based pathways targeting SKA1 were identified: lncRNA: AC026401.3, Small Nucleolar RNA Host Gene 3 (SNHG3), and AC124798.1-miR-139-5p-SKA1; lncRNA: AC26356.1, Small Nucleolar RNA Host Gene 16 (SNHG16), and FGD5 Antisense RNA 1-miR-22-3p-SKA1; lncRNA: Cytoskeleton Regulator RNA (CYTOR), MIR4435-2 Host Gene, and differentiation antagonizing non-protein coding RNA-miR-125b-5p-SKA1. SKA1 expression levels significantly correlated with immune cell infiltration and immune checkpoint genes in the HCC tissues. SKA1 is a potential prognostic biomarker for HCC. This study provides a meaningful direction for research on SKA1-related mechanisms, which will be beneficial for future research on HCC-related molecular biological therapies and targeted immunotherapy.

Pancancer analysis of SKA1 mutation and its association with the diagnosis and prognosis of human cancers

This study aims to explore the role of SKA1 in cancer diagnosis and prognosis and to investigate the mechanism by which SKA1 affects the malignant behaviors of ovarian cancer. Herein, we analyzed the oncogenic role of SKA1 at pan-cancer level by multiple informatics databases and verified the analysis by in vitro experiments. As a result, SKA1 was upregulated across cancers and was related to poor clinical outcome and immune infiltration. Specifically, the constructed nomogram showed superior performance in predicting the prognosis of epithelial ovarian cancer patients. Furthermore, the in vitro experiments revealed that silencing SKA1 significantly inhibited the proliferation, migratory ability and enhanced the cisplatin sensitivity of ovarian cancer cells. Therefore, we explored the oncogenic and potential therapeutic role of SKA1 across cancers through multiple bioinformatic analysis and revealed that SKA1 may promote ovarian cancer progression and chemoresistance to cisplatin by activating the AKT-FOXO3a signaling pathway.

The Higher Expression of CDCA2 Associated with Poor Prognosis in Glioma

Glioma is the most common primary intracranial tumor and is related to poor clinical outcomes. The developments of sensitive markers can be applied to reveal the mechanisms involved in the progression of glioma. This study examined CDCA2 expression in glioma samples and its significance in predicting glioma patient outcome. GEPIA and GEO datasets were used to explore the expression of CDCA2 in glioma. Kaplan-Meier and multivariate assays were applied to delve into the prognostic values of CDCA2 expression in glioma patients using CGGA datasets. Our group also determined the associations between CDCA2 and clinical characteristics. Coexpression analysis was performed. In this research, we observed that CDCA2 expression was distinctly upregulated in glioma specimens compared with nontumor specimens. The prognosis of glioma with high CDCA2 expression was distinctly worse compared with that of glioma with low CDCA2 expression. Additionally, multivariate Cox regression analysis revealed that high CDCA2 expression was an independent poor prognostic indicator for glioma patients. High expression of CDCA2 was positively associated with advanced clinical progression. Coexpression analysis revealed that CDCA2 could be positively related to ASPM, SKA1, DLGAP5, NCAPG, and CDCA8 and was negatively associated with ETNPPL, LDHD, MRVI1, CBX7, and CENPJ. Overall, our findings revealed that CDCA2 might serve as an independent prognosis indicator for glioma.

ETV5 overexpression promotes progression of esophageal squamous cell carcinoma by upregulating SKA1 and TRPV2

Esophageal squamous cell carcinoma (ESCC) is notorious for the rapid progression especially early tumor metastasis due to the unclear mechanism. Recently, ETV5 attracts much attention for its potential role as an oncogenic transcription factor involved in multiple cancers. However, no one reported the mechanism behind the association between ETV5 expression and esophageal squamous cell carcinoma progression. In this study, we found that ETV5 was upregulated in ESCC both from online database and our ESCC tissues and ETV5 was associated with tumor staging and prognosis. Knockdown of ETV5 or its downstream genes SKA1 and TRPV2 significantly suppress ESCC cells migration and invasion, respectively. Additionally, in vivo study showed knockdown of ETV5 inhibited tumor metastasis. Further experiments unveiled ETV5 could transcriptionally upregulate the expression of SKA1 and TRPV2 and further activate MMPs in ESCC progression. In conclusion, ETV5 was associated with ESCC tumor staging and ESCC prognosis clinically. ETV5 promoted metastasis of ESCC by activating MMPs through augmenting the transcription of SKA1 and TRPV2. ETV5 was likely to be a novel oncogene and therapeutic target in ESCC.

Integrative analysis of prognostic value and immune infiltration of spindle and kinetochore-associated family members in breast cancer

Spindle and kinetochore associated (SKA) complex subunit, which maintains the stability of mitotic metaphase, with emerging research implying its effect as a carcinogenic regulator in cancer. However, its potential role in BC has not been fully elucidated. ONCOMINE, UALCAN, GEPIA, Kaplan-Meier Plotter, cBioPortal and TIMER databases were performed to analyze the expression, prognosis, mutation, immune infiltration and potential biological mechanisms of SKA1/2/3 in BC. Our results showed that SKA1/2/3 expression was upregulated in BC. Survival analysis reveals that SKA3 overexpression was associated with poor overall survival (OS), relapse-free survival (RFS), post-progression survival (PPS) and distant metastasis-free survival (DMFS). SKA1 overexpression was associated with poor OS, RFS and DMFS while SKA2 overexpression was only associated with RFS and DMFS. Notably, the results implied that SKA1 has a good prognostic value in HER2-positive BC. Besides, the genetic alterations of SKA were investigated and the altered group correlated with shorter progress-free survival (PFS) and disease-specific survival (DSS). GO and KEGG analysis showed that SKA1/2/3 were implicated in regulating cell cycle, p53 signaling pathway and DNA replication. The 10 Hub genes in the protein network were upregulated in BC and related to poorer prognosis. Additionally, SKA1/2/3 expression was negatively correlated with infiltration of various immune cells with antitumor effects, whereas positively correlated with the expression of immune checkpoints molecules. Further experiments revealed that SKA1/2/3 silencing markedly impeded the proliferation and migration of BC cells. Herein, our study firmly shows that SKA genes may serve as a promising therapeutic target for patients with BC.

Circular RNA FAT atypical cadherin 1 (circFAT1)/microRNA-525-5p/spindle and kinetochore-associated complex subunit 1 (SKA1) axis regulates oxaliplatin resistance in breast cancer by activating the notch and Wnt signaling pathway

Increasing evidence has confirmed the vital roles of circular RNAs (CircRNAs) in the drug resistance of breast cancer (BC). Herein, we intended to study the effect of circular RNA FAT atypical cadherin 1 (circFAT1) on BC oxaliplatin (OX) resistance and find out the potential molecular mechanism in it. In this study, mRNA and protein levels of genes were measured by RT-qPCR and western blotting, respectively. Luciferase reporter assay confirmed the relationship between microRNA-525-5p (miR-525-5p) and circFAT1 or spindle and kinetochore-associated complex subunit 1 (SKA1). CCK-8, transwell, and flow cytometry experiments were utilized to investigate the chemosensitivity, migration, invasion, and apoptosis of BC cells. Gene Set Enrichment Analysis (GSEA) was applied to discover possible pathways related to SKA1. It was uncovered that circFAT1 was overexpressed in OX-resistant BC tissues and cells. Functional experiments showed that circFAT1 depletion reduced the level of chemoresistance-related genes. Moreover, circFAT1 knockdown remarkably facilitated apoptosis and decreased OX (half-maximal inhibitory concentration) IC₅₀ value, migration, and invasion in OX-resistant BC cells. It was identified that miR-525-5p directly targeted circFAT1 and SKA1. Besides, rescue assays exhibited that circFAT1 promoted OX resistance in BC cells via the miR-525-5p/SKA1 regulatory network. Furthermore, GSEA and western blotting identified that SKA1 activated the Notch and Wnt pathway in OX-resistant BC cells. In conclusion, our results demonstrated that circFAT1 conferred OX resistance in BC by regulating the miR-525-5p/SKA1 via the Notch and Wnt pathway, providing a potential therapeutic target for patients with OX-resistant BC.

miRNA-10a-5p inhibits cell metastasis in hepatocellular carcinoma via targeting SKA1

A variety of microRNAs (miRNAs) are involved in the occurrence and development of hepatocellular carcinoma (HCC). However, the role of miR-10a-5p in the progression of HCC remains unclear. Therefore, the purpose of this study was to determine the role of miR-10a-5p in the development of HCC and the possible molecular mechanism. miR-10a-5p expression in HCC tissues and plasma from patients was detected by quantitative real-time polymerase chain reaction. Migratory changes in HCC cells were detected after the overexpression of miR-10a-5p. Epithelial-mesenchymal transition (EMT)-related proteins were detected by Western blot. Finally, through luciferase assay and rescue experiments, the mechanism by which miR-10a-5p regulates its downstream gene, human spindle and kinetochore-associated complex subunit 1, SKA1 and the interaction between these molecules in the development of HCC were determined. The expression of miR-10a-5p was markedly downregulated in HCC tissues, cell lines, and plasma. The overexpression of miR-10a-5p significantly inhibited the migration, invasion, and EMT of HCC cells. Furthermore, SKA1 was shown to be a downstream gene of miR-10a-5p. SKA1 silencing had the same effect as miR-10a-5p overexpression in HCC. In particular, the overexpression of SKA1 reversed the inhibitory effects of miR-10a-5p in HCC. Taken together, low miR-10a-5p expression is associated with HCC progression. miR-10a-5p inhibits the malignant development of HCC by negatively regulating SKA1.

Identification of HCG18 and MCM3AP-AS1 That Associate With Bone Metastasis, Poor Prognosis and Increased Abundance of M2 Macrophage Infiltration in Prostate Cancer

Background:

Bone metastasis is a leading cause of the high mortality rate of prostate cancer (PCa), but curative strategies remain lacking. Recent studies suggest long non-coding RNAs (lncRNAs) may be potential targets to develop drugs. However, PCa bone metastasis-specifically-related lncRNAs were rarely reported. This study aimed to identify crucial lncRNAs and reveal their function mechanisms.

Methods:

GSE32269 and GSE26964 microarray datasets, downloaded from the Gene Expression Omnibus database, were used to analyze differentially expressed genes (DEGs)/lncRNAs (DELs) and miRNAs (DEMs), respectively. Weighted gene co-expression network analysis was performed to screen PCa bone metastasis-associated modules. The co-expression and competing endogenous RNAs (ceRNAs) networks were constructed to identify hub lncRNAs. Univariate Cox regression analysis was conducted to determine their prognostic values. The correlation of lncRNAs with immune infiltrating cells was analyzed by using Tumor IMmune Estimation Resource. Therapeutic drugs were predicted by querying the Connectivity Map (CMap) and the Comparative Toxicogenomics Database (CTD).

Results:

A total of 18 DELs, 2,614 DEGs and 86 DEMs were screened between bone metastatic and primary PCa samples. Four modules enriched by DEGs were shown to be bone metastasis-associated. LncRNA HCG18 and MCM3AP-AS1 were identified to be important because they existed in both of the co-expression and ceRNA networks (forming the relationship pairs: HCG18/MCM3AP-AS1-KNTC1, MCM3AP-AS1-hsa-miR-508-3p-DTL and HCG18/MCM3AP-AS1-hsa-miR-127-3p-CDKN3). All the genes in these interaction pairs were significantly associated with overall survival of PCa patients. Also, HCG18, MCM3AP-AS1 and their target mRNAs were positively correlated with various tumor-infiltrated immune cells, especially increased M2 macrophages. Valproic acid and trichostatin A may be effective to treat PCa bone metastasis by targeting HCG18 and MCM3AP-AS1.

Conclusion:

HCG18 and MCM3AP-AS1 that regulate M2 macrophage infiltration may be important targets to treat PCa bone metastasis and improve prognosis.

Identification of Spindle and Kinetochore-Associated Family Genes as Therapeutic Targets and Prognostic Biomarkers in Pancreas Ductal Adenocarcinoma Microenvironment

Aim

The role of spindle and kinetochore-associated (SKA) genes in tumorigenesis and cancer progression has been widely studied. However, so far, the oncogenic involvement of SKA family genes in pancreatic cancer and their prognostic potential remain unknown.

Methods

Here, we carried out a meta-analysis of the differential expression of SKA genes in normal and tumor tissue. Univariate and multivariate survival analyses were done to evaluate the correlation between SKA family gene expression and pancreas ductal adenocarcinoma (PDAC) prognosis. Joint-effect and stratified survival analysis as well as nomogram analysis were used to estimate the prognostic value of genes. The underlying regulatory and biological mechanisms were identified by Gene set enrichment analysis. Interaction between SKA prognosis-related genes and immune cell infiltration was assessed using the Tumor Immune Estimation Resource tool.

Results

We find that SKA1-3 are highly expressed in PDAC tissues relative to non-cancer tissues. Survival analysis revealed that high expression of SKA1 and SKA3 independently indicate poor prognosis but they are not associated with relapse-free survival. The prognostic value of SKA1 and SKA3 was further confirmed by the nomogram, joint-effect, and stratified survival analysis. Analysis of underlying mechanisms reveals that these genes influence cancer-related signaling pathways, kinases, miRNA, and E2F family genes. Notably, prognosis-related genes are inversely correlated with several immune cells infiltrating levels.

Conclusion

We find that SKA1 and SKA3 expression correlates with prognosis and immune cell infiltration in PDAC, highlighting their potential as pancreatic cancer prognostic biomarkers.