SKA3 promotes lung adenocarcinoma metastasis through the EGFR-PI3K-Akt axis

Based on Network Pharmacology and Molecular Docking, the Active Components, Targets, and Mechanisms of Flemingia philippinensis in Improving Inflammation Were Excavated

Flemingia philippinensis, a polyphenol-rich plant, holds potential for improving inflammation, but its mechanisms are not well understood. Therefore, this study employed network pharmacology and molecular docking to explore the mechanism by which Flemingia philippinensis ameliorates inflammation. In this study, 29 kinds of active ingredients were obtained via data mining. Five main active components were screened out for improving inflammation, which were flemichin D, naringenin, chrysophanol, genistein and orobol. In total, 52 core targets were identified, including AKT serine/threonine kinase 1 (AKT1), tumor necrosis factor (TNF), B-cell lymphoma-2 (BCL2), serum albumin (ALB), and estrogen receptor 1 (ESR1). Gene ontology (GO) enrichment analysis identified 2331 entries related to biological processes, 98 entries associated with cellular components, and 203 entries linked to molecular functions. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis yielded 149 pathways, including those involved in EGFR tyrosine kinase inhibitor resistance, endocrine resistance, and the PI3K-Akt signaling pathway. Molecular docking results showed strong binding effects between the main active components and the core targets, with binding energies less than -5 kcal/mol. In summary, this study preliminarily elucidated the underlying mechanisms by which Flemingia philippinensis, through a multi-component, multi-target, and multi-pathway approach, ameliorates inflammation. This provides a theoretical foundation for the subsequent application of Flemingia philippinensis in inflammation amelioration.

SKA3 Expression as a Prognostic Factor for Patients with Pancreatic Adenocarcinoma

The spindle and kinetochore-associated complex subunit 3 (SKA3) is a protein essential for proper chromosome segregation during mitosis and thus responsible for maintaining genome stability. Although its involvement in the pathogenesis of various cancer types has been reported, the potential clinicopathological significance of SKA3 in pancreatic ductal adenocarcinoma (PDAC) has not been fully elucidated. Therefore, this study aimed to assess clinicopathological associations and prognostic value of SKA3 in PDAC. For this purpose, in-house immunohistochemical analysis on tissue macroarrays (TMAs), as well as a bioinformatic examination using publicly available RNA-Seq dataset, were performed. It was demonstrated that SKA3 expression at both mRNA and protein levels was significantly elevated in PDAC compared to control tissues. Upregulated mRNA expression constituted an independent unfavorable prognostic factor for the overall survival of PDAC patients, whereas altered SKA3 protein levels were associated with significantly better clinical outcomes. The last observation was particularly clear in the early-stage tumors. These findings render SKA3 a promising prognostic biomarker for patients with pancreatic ductal adenocarcinoma. However, further studies are needed to confirm this conclusion.

TFAP2A Upregulates SKA3 to Promote Glycolysis and Reduce the Sensitivity of Lung Adenocarcinoma Cells to Cisplatin

INTRODUCTION

Studies have shown that glycolysis metabolism affects the resistance or sensitivity of tumors to chemotherapy drugs. Emerging from recent research, a paradigm-shifting revelation has unfolded, elucidating the oncogenic nature of SKA3 within the context of lung adenocarcinoma (LUAD). Consequently, this work was designed to delve into the effects of SKA3 on glycolysis and cisplatin (CDDP) resistance in LUAD cells and to find new possibilities for individualized treatment of LUAD.

METHODS

LUAD mRNA expression data from the TCGA database were procured to scrutinize the differential expression patterns of SKA3 in both tumor and normal tissues. GSEA and Pearson correlation analyses were employed to elucidate the impact of SKA3 on signaling pathways within the context of LUAD. In order to discern the upstream regulatory mechanisms, the ChEA and JASPAR databases were utilized to predict the transcription factors and binding sites associated with SKA3. qRT-PCR and Western blot were implemented to assay the mRNA and protein expression levels of SKA3 and TFAP2A. Chromatin immunoprecipitation and dual-luciferase assays were performed to solidify the binding relationship between the two. Extracellular acidification rate, glucose consumption, lactate production, and glycolysis-related proteins (HK2, GLUT1, and LDHA) were used to evaluate the level of glycolysis. Cell viability under CDDP treatment was determined utilizing the CCK-8, allowing for the calculation of IC50. The expression levels of SKA3 and TFAP2A proteins were detected by immunohistochemistry (IHC).

RESULTS

SKA3 exhibited upregulation in LUAD tissues and cell lines, establishing a direct linkage with glycolysis pathway. Overexpression of SKA3 fostered glycolysis in LUAD, resulting in reduced sensitivity toward CDDP treatment. The upstream transcription factor of SKA3, TFAP2A, was also upregulated in LUAD and could promote SKA3 transcription. Overexpression of TFAP2A also fostered the glycolysis of LUAD. Rescue assays showed that TFAP2A promoted glycolysis in LUAD cells by activating SKA3, reducing the sensitivity of LUAD cells to CDDP. The IHC analysis revealed a positive correlation between high expression of SKA3 and TFAP2A and CDDP resistance.

CONCLUSION

In summary, TFAP2A can transcriptionally activate SKA3, promote glycolysis in LUAD, and protect LUAD cells from CDDP treatment, indicating that targeting the TFAP2A/SKA3 axis may become a plausible and pragmatic therapeutic strategy for the clinical governance of LUAD.

SKA3 targeted therapies in cancer precision surgery: bridging bench discoveries to clinical applications - review article

Spindle and kinetochore-associated complex subunit 3 (SKA3) is a microtubule-binding subcomplex of the outer kinetochore, which plays a vital role in proper chromosomal segregation and cell division. Recently, SKA3 have been demonstrated its oncogenic role of tumorigenesis and development in cancers. In this review, the authors comprehensively deciphered SKA3 in human cancer from various aspects, including bibliometrics, pan-cancer analysis, and narrative summary. The authors also provided the top 10 predicted drugs targeting SKA3. The authors proposed that SKA3 was a potential target and brought new therapeutic opportunities for cancer patients.

Spindle and kinetochore-related complex subunit 3 has a protumour function in osteosarcoma by activating the Notch pathway

Increasing expression of spindle and kinetochore-related complex subunit 3 (SKA3) is related to the progression of multiple malignancies. However, the role of SKA3 in osteosarcoma remains unexplored. The present study aimed to investigate the relevance of SKA3 in osteosarcoma. Preliminarily, SKA3 expression in osteosarcoma was assessed through The Cancer Genome Atlas (TCGA) analysis, which revealed high levels of SKA3 transcripts in osteosarcoma tissues. Subsequent examination of clinical tissues confirmed the abundant expression of SKA3 in osteosarcoma. Downregulation of SKA3 expression in osteosarcoma cell lines resulted in repressive effects on cell proliferation, migration, invasion, and epithelial-to-mesenchymal transition (EMT), while upregulation of SKA3 expression had the opposite effect. Gene set enrichment analysis (GSEA) revealed that the Notch pathway is enriched in SKA3 high groups based on different expressed genes from the TCGA data. Further investigation showed that the levels of Notch1, Notch1 intracellular domain (NICD1), hairy and enhancer of split 1 (HES1), and hairy/enhancer-of-split related with YRPW motif protein 1 (HEY1) were downregulated in SKA3-silenced osteosarcoma cells, and upregulated in SKA3-overexpressed osteosarcoma cells. Activation of the Notch pathway by increasing NICD1 expression reversed the antitumour effects induced by SKA3 silencing, while deactivation of the Notch pathway diminished the protumour effects induced by SKA3 overexpression. Moreover, SKA3-silenced osteosarcoma cells exhibited a reduced capacity for xenograft formation in nude mice. In conclusion, SKA3 plays a cancer-enhancing role in osteosarcoma through its effect on the Notch pathway. Reducing the expression of SKA3 could be a potential therapeutic approach for treating osteosarcoma.

High spindle and kinetochore-associated complex subunit-3 expression predicts poor prognosis and correlates with adverse immune infiltration in hepatocellular carcinoma

BACKGROUND

Spindle and kinetochore-associated complex subunit 3 (SKA3) is a malignancy-associated gene that plays a critical role in the regulation of chromosome separation and cell division. However, the molecular mechanism through which SKA3 regulates tumor cell proliferation in hepatocellular carcinoma (HCC) has not been fully elucidated.

AIM

To investigate the molecular mechanisms underlying the role of SKA3 in HCC.

METHODS

SKA3 expression, clinicopathological, and survival analyses were performed using multiple public database platforms, and the results were verified by Western blot and immunohistochemistry staining using collected clinical samples. Functional enrichment analyses were performed to evaluate the biological functions and molecular mechanisms of SKA3 in HCC. Furthermore, the Tumor Immune Estimation Resource and single-sample Gene Set Enrichment Analysis (ssGSEA) algorithms were utilized to investigate the abundance of tumor-infiltrating immune cells in HCC. The response to chemotherapeutic drugs was evaluated by the R package "pRRophetic".

RESULTS

We found that upregulated SKA3 expression was significantly correlated with poor prognosis in patients with HCC. Multivariable Cox regression analysis indicated that SKA3 was an independent risk factor for survival. GSEA revealed that SKA3 expression may facilitate proliferation and migratory processes by regulating the cell cycle and DNA repair. Moreover, patients with high SKA3 expression had significantly decreased ratios of CD8+ T cells, natural killer cells, and dendritic cells. Drug sensitivity analysis showed that the high SKA3 group was more sensitive to sorafenib, sunitinib, paclitaxel, doxorubicin, gemcitabine, and vx-680.

CONCLUSION

High SKA3 expression led to poor prognosis in patients with HCC by enhancing HCC proliferation and repressing immune cell infiltration surrounding HCC. SKA3 may be used as a biomarker for poor prognosis and as a therapeutic target in HCC.

Integrating Network Pharmacology and Experimental Validation to Elucidate the Mechanism of Yiqi Yangyin Decoction in Suppressing Non-Small-Cell Lung Cancer

Yiqi Yangyin Decoction (YYD) is a classic traditional Chinese medicine (TCM) formulation to treat lung cancer in clinic. Nevertheless, the active ingredients, key targets, and molecular mechanisms for YYD are still poorly understood. This study is focused on elucidating the pharmacological mechanism of YYD in non-small-cell lung cancer (NSCLC) by using a combined network pharmacology approach and biological experiment validation. Online bioinformatics tools showed that 40 bioactive compounds and 229 putative targets of YYD were associated with anti-NSCLC activity. Protein-Protein Interaction (PPI) network demonstrated AKT1, SRC, JUN, TP53, and EGFR as the top five key targets for YYD against NSCLC. Through enrichment analysis, YYD was found to affect cell proliferation and apoptosis in NSCLC possibly by PI3K-AKT signaling. Molecular docking confirmed a strong binding between the main compounds (quercetin or luteolin) and EGFR. As demonstrated by CCK-8, EdU, and colony formation assays, we found a significant inhibition of YYD on cell proliferation. Moreover, YYD treatment induced cell cycle arrest by affecting p53, p21, and cyclin D1 expression. YYD administration enhanced apoptosis by changing the expression of cleaved caspase-3, Bax, and Bcl-2. Mechanistically, YYD resulted in a significant inactivation of EGFR-PI3K-AKT signaling. Furthermore, EGFR activator significantly reversed YYD-mediated proliferation inhibition and apoptosis. YYD also showed an inhibitory effect on tumor growth in mice. Together, YYD might target the EGFR-PI3K-AKT pathway to repress NSCLC progression.

Transcription factor ZEB1 regulates PLK1-mediated SKA3 phosphorylation to promote lung cancer cell proliferation, migration and cell cycle

Lung cancer (LC) is one of the most common malignancies worldwide with low 5-year survival rate. The mechanism of spindle and kinetochore-associated complex subunit 3 (SKA3) in LC tumorgenesis remains largely unclear. The expression of SKA3 in LC cells was detected by quantitative PCR. Cell proliferation, migration and cell cycle were evaluated by functional assays including 5-ethynyl-2'-deoxyuridine, wound healing, transwell assays and flow cytometry analysis. Bioinformatics analysis, chromatin immunoprecipitation, luciferase reporter, co-immunoprecipitation and in vitro phosphorylation assays were applied to explore the interactions between zinc finger E-box binding homeobox 1 (ZEB1) and SKA3/polo-like kinase 1 (PLK1). SKA3 is highly expressed in LC cell lines and drives LC cell proliferation, migration and cell cycle. PLK1 also enhances the malignancy of LC cells. PLK1 can mediate SKA3 phosphorylation and enhance the stability of SKA3 protein, thus promoting LC progression. Besides, we found that transcription factor ZEB1 transcriptionally activates SKA3/PLK1 expression, contributing to LC cell malignancy. This study demonstrated that transcription factor ZEB1 modulates PLK1-mediated SKA3 phosphorylation to accelerate LC cell growth, migration and cycle, which might offer novel insight into LC treatment.

SKA1/2/3 is a biomarker of poor prognosis in human hepatocellular carcinoma

BACKGROUND

Spindle and kinetochore-associated complex subunits 1-3 (SKA1-3) stabilize the kinetochore-attached spindle microtubules in metaphase. Due to the dysregulation in multiple cancers, SKA1-3 is considered a predictor for the prognosis of the patients. However, the potential clinical applications of SKA1-3, particularly in hepatocellular carcinoma (HCC) prognosis and progression, have completely unknown yet.

METHODS

For the analysis of SKA1-3 expression and applications in clinics in HCC patients, several databases, such as STRING, UALCAN, GEO, and TCGA, were searched. In addition, the underlying mechanisms of SKA for the regulation of HCC occurrence, development, and progression were also explored.

RESULTS

Compared to the normal controls, HCC patients showed dramatically elevated SKA1-3 expression at the mRNA level, and the values of the area under the curve (AUC) were 0.982, 0.887, and 0.973, respectively. Increased SKA1-3 expression levels were associated with the clinical stage, age, body mass index, tumor grade, tissue subtype, and Tp53 mutation status in HCC patients. The analyses of Kyoto Encyclopedia of Genes and Genome (KEGG) and Gene ontology (GO) demonstrated that SKA1-3 are enriched mainly in the Fanconi anemia, homologous recombination, spliceosome, DNA replication, and cell cycle signaling pathways. The hub genes, such as CDK1, CCNB1, CCNA2, TOP2A, BUB1, AURKB, CCNB2, BUB1B, NCAPG, and KIF11, were identified in protein-protein interactions (PPIs). The expression levels of hub genes were increased in HCC patients and predictive of a poor prognosis. Finally, the expression levels of SKA1-3 were determined using the GEO database.

CONCLUSIONS

SKA1-3 are potential prognostic biomarkers of and targets for HCC. In addition, SKA1-3 may affect HCC prognosis via the Fanconi anemia pathway, homologous recombination, spliceosome, DNA replication, and cell cycle signaling pathway.

Spindle and kinetochore-associated complex subunit 3 could serve as a prognostic biomarker for prostate cancer

Spindle and kinetochore-associated complex subunit 3 (SKA3) is a microtubule-binding subcomplex of the outer kinetochore that is required for proper chromosomal segregation and cell division. However, little is known regarding the probable mechanism of SKA3, particularly in terms of prostate cancer (PCA) progression. Multiple databases, including TCGA and GTEx, were utilized to examine the expression of SKA3 in PCA patients and to shed light on the clinical significance and potential mechanism of SKA3 in the onset and progression of PCA. The biological function of SKA3 was evaluated in vitro using RT-qPCR and the CCK8 assay. For statistical analysis, the R 3.6.3 software and its associated packages were utilized. SKA3 was shown to be considerably elevated in PCA patients and was linked to a shorter progress free interval (PFI). Furthermore, we discovered that SKA3 mRNA expression was higher in PCA cells than in normal cells, and inhibition of SKA3 could clearly reduce PCA cell proliferation using the CCK8 assay. Finally, SKA3 could be used as a predictive biomarker in PCA patients.

CD73 (NT5E) Promotes the Proliferation and Metastasis of Lung Adenocarcinoma through the EGFR/AKT/mTOR Pathway

Introduction

Lung cancer is the most common malignant tumor and the main cause of tumor-related death globally. As the 5-year survival rate of lung adenocarcinoma (LUAD) remains low, it is necessary to investigate novel molecular markers and therapeutic targets for LUAD.

Materials and Methods

The protein expression of CD73 (NT5E) in LUAD specimens was analyzed using immunohistochemistry. Reverse transcription-quantitative PCR and western blot analysis were used to analyze the mRNA and protein expression levels of several genes in LUAD cells. The proliferation of LUAD cells was evaluated using proliferation and colony formation assays and apoptosis analysis. Wound healing and Transwell invasion assays were used to analyze the migration and invasion of the A549 cells, respectively. In addition, overexpression plasmids and small interfering RNAs were used to overexpress or knockdown the expression levels of CD73 in the A549 cell line, respectively. Finally, the interaction between CD73 and EGFR in the A549 cell line was analyzed using immunoprecipitation.

Results

Our research emphasized the importance of CD73 in the prognosis of LUAD and highlighted it as a potential therapeutic target. We also found that the mRNA and protein expression levels of CD73 are increased in LUAD specimens and cell lines and were associated with a poor prognosis in patients with LUAD. Furthermore, it was revealed that CD73 may promote the proliferation, migration, and invasion of the A549 cell line. Finally, we demonstrated that CD73 could bind epidermal growth factor receptor (EGFR) to further regulate the activation of the AKT/mTOR signaling pathway.

Conclusions

CD73 promotes LUAD proliferation and metastasis through EGFR/AKT/mTOR axis.

Overexpression of SKA3 correlates with poor prognosis in female early breast cancer

BACKGROUND

Spindle and kinetochore associated complex subunit 3 (SKA3) plays an important role in tumorigenesis and the progression of various tumors. But the relationship between SKA3 and early breast cancer remains unclear. The study aimed to explore the prognostic significance of SKA3 in breast cancer.

METHODS

In the study, SKA3 expression was initially assessed using the Oncomine database and The Cancer Genome Atlas database (TCGA). Then, we presented validation results for RT-qPCR (quantitative reverse transcription PCR) and ELISA (enzyme-linked immunosorbent assay). The relationship between clinical characteristics and SKA3 expression was assessed by Chi-square test and Fisher's exact test. Kaplan-Meier method and Cox regression analysis were conducted to evaluate the prognostic value of SKA3. Gene set enrichment analysis (GSEA) was performed to screen biological pathways using the TCGA dataset. Besides, single sample gene set enrichment analysis (ssGSEA) was utilized to identify immune infiltration cells about SKA3.

RESULTS

SKA3 mRNA was expressed at high levels in breast cancer tissues compared with normal tissues. Chi-square test and Fisher's exact test showed SKA3 expression was related to age, tumor (T) classification, node (N) classification, tumor-node-metastasis (TNM) stage, estrogen receptor (ER), progesterone receptor (PR), molecular subtype, and race. RT-qPCR results showed that SKA3 expression was overexpressed in ER, PR status, and molecular subtype in Chinese people. Kaplan-Meier curves implicated that high SKA3 expression was related to a poor prognosis in female early breast cancer patients. Cox regression models showed that high SKA3 expression could be used as an independent risk factor for female early breast cancer. Four signaling pathways were enriched in the high SKA3 expression group, including mTORC1 signaling pathway, MYC targets v1, mitotic spindle, estrogen response early. Besides, the SKA3 expression level was associate with infiltrating levels of activated CD4 T cells and eosinophils in breast cancer.

CONCLUSION

High SKA3 expression correlates with poor prognosis and immune infiltrates in breast cancer. SKA3 may become a biomarker for the prognosis of breast cancer.

Regulation of Oncogenic Targets by Tumor-Suppressive miR-150-3p in Lung Squamous Cell Carcinoma

Several recent studies have shown that both strands of certain miRNAs derived from miRNA duplexes are involved in cancer pathogenesis. Our own recent studies revealed that both strands of the miR-150 duplex act as tumor-suppressive miRNAs in lung adenocarcinoma (LUAD) through the targeting of several oncogenes. The aim of the study here was to further investigate the tumor-suppressive roles of miR-150-3p (the passenger strand) in lung squamous cell carcinoma (LUSQ) and its control of cancer-promoting genes in LUSQ cells. The downregulation of miR-150-3p in LUSQ tissues was confirmed by data in The Cancer Genome Atlas (TCGA). The ectopic expression of miR-150-3p attenuated cancer cell aggressive features, e.g., cell cycle arrest, migration and invasive abilities. Our target search strategy successfully identified a total of 49 putative targets that were listed as subjects of miR-150-3p regulation in LUSQ cells. Interestingly, among these targets, 17 genes were categorized as related to the “cell cycle” based on Gene Ontology (GO) classification, namely CENPA, CIT, CCNE1, CCNE2, TIMELESS, BUB1, MCM4, HELLS, SKA3, CDCA2, FANCD2, NUF2, E2F2, SUV39H2, CASC5, ZWILCH and CKAP2). Moreover, we show that the expression of HELLS (helicase, lymphoid specific) is directly controlled by miR-150-3p, and its expression promotes the malignant phenotype of LUSQ cells.

SKA3 Serves as a Biomarker for Poor Prognosis in Kidney Renal Papillary Cell Carcinoma

Background

There is a surprising paucity of studies investigating the potential mechanism of SKA3 in the progression and prognosis of kidney renal papillary cell carcinoma (KIRP).

Methods

We used TCGA and other databases to analyze the expression, clinical value, and potential mechanisms of SKA3 in KIRP patients. We also explored therapeutic agents for KIRP through GSCALite.

Results

SKA3 mRNA expression was significantly upregulated and the area under the curve was 0.792 (95% CI 0.727–0.856). Increased SKA3 expression was related to shorter overall survival, disease-specific survival and progression-free survival. Hub genes in protein–protein interactions were CDK1, CDC20, CCNB1, CCNA2, BUB1, AURKB, BUB1B, PLK1, CCNB2, and MAD2L1, which were differentially expressed and also associated with KIRP prognosis. Gene-set enrichment analysis indicated that E2F targets, epithelial–mesenchymal transition, glycolysis, the WNT signaling pathway, and other pathways were highly enriched upon SKA3 upregulation. Gene-set variation analysis of SKA3 and its ten hub genes showed that the significant correlation of cancer-related pathways included the cell cycle, DNA damage, hormone androgen receptor, hormone estrogen receptor, PI3K/Akt, and Ras/MAPK. In addition, we found that MEK inhibitors, ie, trametinib, selumetinib, PD0325901, and RDEA119, may be feasible targeting agents for KIRP patients.

Conclusion

SKA3 might contribute to poor prognosis of KIRP through cell cycle, DNA damage, hormone androgen receptor, hormone estrogen receptor, PI3K/Akt, and RAS/MAPK. SKA3 potentially serves as a prognostic biomarker and target for KIRP.

Construction of a circular RNA-microRNA-messenger RNA regulatory network of hsa_circ_0043256 in lung cancer by integrated analysis

BACKGROUND

Patients with non-small cell lung cancer (NSCLC) are diagnosed in advanced stages and with a poor 5-year survival rate. There is a critical need to identify novel biomarkers to improve the therapy and overall prognosis of this disease.

METHODS

Differentially expressed genes (DEGs) were identified from three profiles of GSE101586, GSE101684 and GSE112214 using Venn diagrams. hsa_circ_0043256 were validated using quantitative real-time polymerase chain reaction (RT-qPCR). The circular RNA-microRNA-messenger RNA (circRNA-miRNA-mRNA) regulatory network was constructed with Cytoscape 3.7.0. Hub genes were identified with protein interaction (PPI) and validated with the Gene Expression Profiling Interactive Analysis (GEPIA), Human Protein Atlas (HPA) databases, and immunohistochemistry. Survival analyses were also performed using a Kaplan-Meier (KM) plotter. The effects of hsa_circ_0043256 on cell proliferation and cell cycles were evaluated by EdU staining and flow cytometry, respectively.

RESULTS

hsa_circ_0043256, hsa_circ_0029426 and hsa_circ_0049271 were obtained. Following RT-qPCR validation, hsa_circ_0043256 was selected for further analysis. In addition, functional experiment results indicated that hsa_circ_0043256 could inhibit cell proliferation and cell-cycle progression of NSCLC cells in vitro. Prediction by three online databases and combining with DEGs identified from The Cancer Genome Atlas (TCGA), a network containing one circRNAs, three miRNAs, and 209 mRNAs was developed. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis indicated DEGs might be associated with lung cancer onset and progression. A PPI network based on the 209 genes was established, and five hub genes (BIRC5, SHCBP1, CCNA2, SKA3, and GINS1) were determined. Following verification of five hub genes using GEPIA database, HPA database, and immunohistochemistry. High expression of all five hub genes led to poor overall survival.

CONCLUSION

Our study constructed a circRNA-miRNA-mRNA network of hsa_circ_0043256. hsa_circ_0043256 may be a potential therapeutic target for lung cancer.

Spindle and kinetochore-associated complex subunit 3 (SKA3) promotes stem cell-like properties of hepatocellular carcinoma cells through activating Notch signaling pathway

Background

Cancer stemness contributes to hepatocellular carcinoma (HCC) initiation, metastasis, drug resistance, and recurrence. The spindle and kinetochore-associated (SKA) complex has been shown to be involved in tumor progression; however, its effects on cancer stem cell-like properties have not yet been examined. This research sought to study each subunit of the SKA complex in HCC systematically.

Methods

Bioinformatic analyses were carried out to examine the expression and clinical data of the SKA complex’s each subunit in HCC. The expression of the target genes was detected by quantitative reverse transcription-polymerase chain reaction and Western blot assays. Clone formation and Transwell assays were performed to assess the proliferation and migration abilities of the SKA complex’s each subunit. Sphere formation assays and subcutaneous xenograft experiments were performed to investigate the effects of SKA complex subunit 3 (SKA3) on the self-renewal and tumorigenic abilities of HCC.

Results

Each subunit of the SKA complex was highly expressed in HCC, but only SKA complex subunit 1 (SKA1) and SKA3 were associated with the poor overall survival of HCC patients. Additionally, the HCC cells overexpressing SKA3 exhibited increased migration, invasion, proliferation, self-renewal, Sorafenib resistance and tumorigenic abilities. Notch signaling played a vital role in the process by which SKA3 promoted HCC stemness.

Conclusions

SKA3 promotes HCC stem cell-like properties via the Notch signaling pathway. As SKA3 appears to act as a regulator of stemness in HCC, it might be a potential molecular target for HCC.

SKA3 overexpression predicts poor outcomes in skin cutaneous melanoma patients

BACKGROUND

Spindle and Kinetochore Associated Complex Subunit 3 (SKA3) is a part of the SKA complex, which plays a key role in cell mitosis. Studies have shown that SKA3 was associated with cancer progression. However, its role in skin cutaneous melanoma (SKCM) remains unclear. Here, we investigated the expression level and prognostic value of SKA3 in SKCM.

METHODS

Based on public databases, univariate and multivariate Cox regression analyses were used to investigate the different expression of SKA3 between SKCM and normal tissues. Then, the relationship between SKA3 expression level and prognosis was assessed. PPI network and functional enrichment analysis were performed. ESTIMATE and CIBERSORT were expected to evaluate the SKA3 expression and immune status. CCK8, wound healing, transwell assays and tumor xenograft trial were performed to detect the SKA3 function in cell viability, migration and invasion of the cell lines.

RESULTS

The SKA3 was highly expressed in SKCM tissues. SKA3 overexpression was associated with poor survival and immune status. SKA3 knockdown inhibited cell viability, migration and invasion of SKCM cells.

CONCLUSION

SKA3 is involved in the progression of SKCM and may serve as a new prognostic biomarker and therapeutic target.

miR-1207-5p suppresses laryngeal squamous cell carcinoma progression by downregulating SKA3 and inhibiting epithelial-mesenchymal transition

Laryngeal squamous cell carcinoma (LSCC) is the second most common head and neck cancer. Previously, we discovered that miR-1207-5p was downregulated in LSCC. In this study, the clinical significance, function, and mechanism of miR-1207-5p in LSCC were investigated. Downregulation of miR-1207-5p was found to be strongly linked to the malignant progression of LSCC. Functional studies revealed that miR-1207-5p upregulation suppressed LSCC cell proliferation, invasion, migration, and xenograft tumor growth. Bioinformatics analysis revealed that miR-1207-5p target genes were involved in cell cycle regulation, proliferation, adhesion, and the phosphatidylinositol 3-kinase (PI3K)/Akt pathway. Mechanistic studies revealed that miR-1207-5p interacts directly with the 3′ untranslated region of spindle and kinetochore associated complex subunit 3 (SKA3) and downregulates SKA3 expression. Furthermore, SKA3 was found to be overexpressed in LSCC, and its high expression was associated with tumor progression and a poor prognosis. Rescue experiments demonstrated that miR-1207-5p inhibited the malignant phenotypes of LSCC via SKA3. Furthermore, miR-1207-5p upregulation or knockdown of SKA3 inhibited the epithelial-mesenchymal transition (EMT). Collectively, miR-1207-5p inhibited LSCC malignant progression by downregulating SKA3 and preventing EMT. These findings provide new insights into the mechanism of LSCC progression, as well as new potential biomarkers and therapeutic targets for LSCC diagnosis and treatment.

Hub Genes and Key Pathways of Intervertebral Disc Degeneration: Bioinformatics Analysis and Validation

Objective

To identify significant pathways and genes in intervertebral disc degeneration (IDD) based on bioinformatics analysis.

Design

The GEO database was used to download the GSE124272 dataset. Differentially expressed genes (DEGs) were analyzed using Limma package in R language. Then, gene ontologies (GO), Kyoto encyclopedia of genes and genomes (KEGG), and protein-protein interaction (PPI) networks were used to further identify hub genes. The mRNA expression levels of top six hub genes were verified.

Results

We found 563 DEGs, of which 214 were upregulated and 349 were downregulated. The top 5 GO terms and pathways were shown including immune response, cell cycle, and p53 pathway. Based on the PPI analysis, we verified the mRNA expression levels of 6 hub genes. The mRNA levels of CHEK1, CDCA2, SKA3, and KIF20A were upregulated in degenerative NP tissue than in healthy NP tissue. However, the mRNA level of BUB1 and SPC25 was downregulated.

Conclusions

This study may provide new biomarkers for the IDD and treatments to repair IDD related to CHEK1, CDCA2, SKA3, BUB1, KIF20A, and SPC25.

Glycolysis Define Two Prognostic Subgroups of Lung Adenocarcinoma With Different Mutation Characteristics and Immune Infiltration Signatures

Increasing studies have proved that malignant tumors are associated with energy metabolism. This study was aimed to explore biological variables that impact the prognosis of patients in the glycolysis-related subgroups of lung adenocarcinoma (LUAD). The mRNA expression profiling and mutation data in large LUAD samples were collected from the Cancer Genome Atlas (TCGA) database. Then, we identified the expression level and prognostic value of glycolysis-related genes, as well as the fractions of 22 immune cells in the tumor microenvironment. The differences between glycolysis activity, mutation, and immune infiltrates were discussed in these groups, respectively. Two hundred fifty-five glycolysis-related genes were identified from gene set enrichment analysis (GSEA), of which 43 genes had prognostic values (p < 0.05). Next, we constructed a glycolysis-related competing endogenous RNA (ceRNA) network which related to the survival of LUAD. Then, two subgroups of LUAD (clusters 1 and 2) were identified by applying unsupervised consensus clustering to 43 glycolysis-related genes. The survival analysis showed that the cluster 1 patients had a worse prognosis (p < 0.001), and upregulated differentially expressed genes (DEGs) are interestingly enriched in malignancy-related biological processes. The differences between the two subgroups are SPTA1, KEAP1, USH2A, and KRAS among top 10 mutated signatures, which may be the underlying mechanism of grouping. Combined high tumor mutational burden (TMB) with tumor subgroups preferably predicts the prognosis of LUAD patients. The CIBERSORT algorithm results revealed that low TMB samples were concerned with increased infiltration level of memory resting CD4+ T cell (p = 0.03), resting mast cells (p = 0.044), and neutrophils (p = 0.002) in cluster 1 and high TMB samples were concerned with increased infiltration level of memory B cells, plasma cells, CD4 memory-activated T cells, macrophages M1, and activated mast cells in cluster 2, while reduced infiltration of monocytes, resting dendritic cells, and resting mast cells was captured in cluster 2. In conclusion, significant different gene expression characteristics were pooled according to the two subgroups of LUAD. The combination of subgroups, TMB and tumor-infiltrating immune cell signature, might be a novel prognostic biomarker in LUAD.

Targeting multiple genes containing long mononucleotide A-T repeats in lung cancer stem cells

BACKGROUND

Intratumour heterogeneous gene expression among cancer and cancer stem cells (CSCs) can cause failure of current targeted therapies because each drug aims to target the function of a single gene. Long mononucleotide A-T repeats are cis-regulatory transcriptional elements that control many genes, increasing the expression of numerous genes in various cancers, including lung cancer. Therefore, targeting A-T repeats may dysregulate many genes driving cancer development. Here, we tested a peptide nucleic acid (PNA) oligo containing a long A-repeat sequence [A(15)] to disrupt the transcriptional control of the A-T repeat in lung cancer and CSCs.

METHODS

First, we separated CSCs from parental lung cancer cell lines. Then, we evaluated the role of A-T repeat gene regulation by counting the number of repeats in differentially regulated genes between CSCs and the parental cells of the CSCs. After testing the dosage and effect of PNA-A15 on normal and cancer cell toxicity and CSC phenotypes, we analysed genome-wide expression to identify dysregulated genes in CSCs.

RESULTS

The number of A-T repeats in genes differentially regulated between CSCs and parental cells differed. PNA-A15 was toxic to lung cancer cells and CSCs but not to noncancer cells. Finally, PNA-A15 dysregulated a number of genes in lung CSCs.

CONCLUSION

PNA-A15 is a promising novel targeted therapy agent that targets the transcriptional control activity of multiple genes in lung CSCs.

SKA3 promotes glioblastoma proliferation and invasion by enhancing the activation of Wnt/β-catenin signaling via modulation of the Akt/GSK-3β axis

Spindle and kinetochore-related complex subunit 3 (SKA3) is a key modulator of the progression of multiple tumor types. However, the involvement of SKA3 in glioblastoma (GBM) has not been well studied. The current study aimed to explore the role of SKA3 expression and the potential function of the protein in GBM. Our data showed that SKA3 expression was significantly up-regulated in GBM. Functional assays demonstrated that the knockdown of SKA3 impeded the proliferation, colony formation and invasion of GBM cells, while SKA3 overexpression produced the opposite effects. Further investigation revealed that SKA3 overexpression enhanced the activation of Wnt/β-catenin signaling, which was associated with the enhanced phosphorylation of Akt and glycogen synthase kinase-3β (GSK-3β). Notably, the inhibition of Akt markedly abrogated the SKA3 overexpression-induced promotion of Wnt/β-catenin signaling in GBM cells. Further, the inhibition of Wnt/β-catenin signaling markedly abrogated the SKA3 overexpression-induced promotion of tumor growth. In addition, the knockdown of SKA3 significantly retarded tumor formation and GBM progression in vivo. In summary, these data demonstrate that SKA3 exerts promotes tumor growth in GBM by enhancing the activation of Wnt/β-catenin signaling via modulation of the Akt/GSK-3β axis. This work highlights the pivotal role of SKA3/Akt/GSK-3β/Wnt/β-catenin signaling in the progression of GBM and suggests that SKA3 is an attractive therapeutic target with potential to be used to treat GBM.

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.

EGFR-rich extracellular vesicles derived from highly metastatic nasopharyngeal carcinoma cells accelerate tumour metastasis through PI3K/AKT pathway-suppressed ROS

Nasopharyngeal carcinoma (NPC) is the most common cancer with high metastatic potential that occurs in the epithelial cells of the nasopharynx. Distant metastases are the primary cause for treatment failure and mortality of NPC patients. However, the underlying mechanism responsible for the initiation of tumour cell dissemination and tumour metastasis in NPC is not well understood. Here, we demonstrated that epidermal growth factor receptor (EGFR) was highly expressed in tumour tissues of NPC patients with distant metastases and was associated with a decrease in reactive oxygen species (ROS). We also revealed that extracellular vesicles (EVs) transfer occurred from highly to poorly metastatic NPC cells, mediating cell-cell communication and enhancing the metastatic potential of poorly metastatic NPC cells. Further experiments indicated that EVs derived from highly metastatic NPC cells induced the up-regulation of EGFR and down-regulation of ROS in low metastatic NPC cells. Mechanistically, EGFR-rich EVs-mediated EGFR overexpression down-regulated intracellular ROS levels through the PI3K/AKT pathway, thus promoting the metastatic potential of poorly metastatic NPC cells. Strikingly, treatment with EVs secreted from highly metastatic NPC cells was significantly associated with rapid NPC progression and shorter survival in xenografted mice. These findings not only improve our understanding of EVs-mediated NPC metastatic mechanism but also have important implications for the detection and treatment of NPC patients accompanied by aberrant EGFR-rich EVs transmission.

Targeting SKA3 suppresses the proliferation and chemoresistance of laryngeal squamous cell carcinoma via impairing PLK1-AKT axis-mediated glycolysis

Spindle and kinetochore-associated complex subunit 3 (SKA3) is a well-known regulator of chromosome separation and cell division, which plays an important role in cell proliferation. However, the mechanism of SKA3 regulating tumor proliferation via reprogramming metabolism is unknown. Here, SKA3 is identified as an oncogene in laryngeal squamous cell carcinoma (LSCC), and high levels of SKA3 are closely associated with malignant progression and poor prognosis. In vitro and in vivo experiments demonstrate that SKA3 promotes LSCC cell proliferation and chemoresistance through a novel role of reprogramming glycolytic metabolism. Further studies reveal the downstream mechanisms of SKA3, which can bind and stabilize polo-like kinase 1 (PLK1) protein via suppressing ubiquitin-mediated degradation. The accumulation of PLK1 activates AKT and thus upregulates glycolytic enzymes HK2, PFKFB3, and PDK1, resulting in enhancement of glycolysis. Furthermore, our data reveal that phosphorylation at Thr360 of SKA3 is critical for its binding to PLK1 and the increase in glycolysis. Collectively, the novel oncogenic signal axis "SKA3-PLK1-AKT" plays a critical role in the glycolysis of LSCC. SKA3 may serve as a prognostic biomarker and therapeutic target, providing a potential strategy for proliferation inhibition and chemosensitization in tumors, especially for LSCC patients with PLK1 inhibitor resistance.

Identification and validation of hub microRNAs dysregulated in esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is one of the deadliest cancers worldwide, and its morbidity is exacerbated by the lack of early symptoms. Bioinformatics analyses enable discovery of differentially expressed genes and non-protein-coding RNAs of potential prognostic and/or therapeutic relevance in ESCC and other cancers. Using bioinformatics tools, we searched for dysregulated miRNAs in two ESCC microarray datasets from the Gene Expression Omnibus (GEO) database. After identification of three upregulated and five downregulated miRNAs shared between databases, protein-protein interaction (PPI) network analysis was used to identify the top 10 hub-gene targets. Thereafter, a miRNA-gene interaction network predicted that most hub genes are regulated by miR-196a-5p and miR-1-3p, which are respectively upregulated and downregulated in ESCC. Functional enrichment analyses in the GO and KEGG databases indicated the potential involvement of these miRNAs in tumorigenesis-related processes and pathways, while both differential expression and correlation with T stage were demonstrated for each miRNA in a cohort of ESCC patients. Overexpression showed that miR-196a-5p increased, whereas miR-1-3p attenuated, proliferation and invasion in human ESCC cell lines grown in vitro. These findings suggest miR-196a-5p and miR-1-3p jointly contribute to ESCC tumorigenesis and are potential targets for diagnosis and treatment.