Spindle and kinetochore associated complex subunit 1 regulates the proliferation of oral adenosquamous carcinoma CAL-27 cells in vitro

Single Cell Analysis of Lung Lymphatic Endothelial Cells and Lymphatic Responses during Influenza Infection

Tissue lymphatic vessels network plays critical roles in immune surveillance and tissue homeostasis in response to pathogen invasion, but how lymphatic system per se is remolded during infection is less understood. Here, we observed that influenza infection induces a significant increase of lymphatic vessel numbers in the lung, accompanied with extensive proliferation of lymphatic endothelial cells (LECs). Single-cell RNA sequencing illustrated the heterogeneity of LECs, identifying a novel PD-L1+ subpopulation that is present during viral infection but not at steady state. Specific deletion of Pd-l1 in LECs elevated the expansion of lymphatic vessel numbers during viral infection. Together these findings elucidate a dramatic expansion of lung lymphatic network in response to viral infection, and reveal a PD-L1+ LEC subpopulation that potentially modulates lymphatic vessel remolding.

SKA1 is overexpressed in laryngocarcinoma and modulates cell growth via P53 signaling pathway

Laryngocarcinoma is one of the most frequent malignancies occurring in the head and neck. The roles of spindle- and kinetochore-associated complex 1 (SKA1) in the malignant progression of several cancers have already been discussed. However, the precise significance and action's mechanism of SKA1 in laryngocarcinoma remain largely unknown. In this study, SKA1 was shown to be strongly expressed in laryngocarcinoma tissues and cells, and higher expression of SKA1 was associated with more severe tumor infiltration, larger tumor diameter, higher risk of lymphatic metastasis and later pathological stage. Additionally, loss-of-function assays in vitro suggested that SKA1 depletion caused a reduction in cell proliferation, migration, and colony formation as well as an increase in apoptosis. In animal experiments, tumors generated from AMC-HN-8 cells with SKA1 depletion exhibited declined tumor volume and weight. Similarly, the detection of Ki67 protein in xenograft tumor tissues reflected that knocking down SKA1 curbed tumor growth in vivo. Further exploration on downstream mechanism revealed that after treatment with Pifithrin-α, the suppression in proliferation level caused by SKA1 knockdown was reversed, while the increase of cell apoptosis was withdrawn; at the molecular level, Pifithrin-α treatment caused p-P53 and Bax diminished, while Bcl-2 ameliorated. In short, SKA1 promotes the development of laryngocarcinoma via activating the P53 signaling pathway.

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.

SKA1 expression in oral squamous cell carcinoma and its relationship to P53 and clinicopathologic features

In this study, 57 paraffin-embedded tissue specimens from patients with oral squamous cell carcinoma (OSCC) were collected and analyzed. Spindle and kinetochore-associated complex subunit 1 (SKA1) and P53 protein expression in selected samples was detected by immunohistochemistry. The positive expression rate of SKA1 and P53 was significantly higher in oral squamous cell carcinoma tissues than in normal controls. The expression of SKA1 protein was significantly associated with tumor-node-metastasis (TNM) stage, and p53 expression was significantly correlated with pathologic differentiation grade in oral squamous cell carcinoma tissues. There was a significant correlation between SKA1 and p53 protein expression in oral squamous cell carcinoma tissues. Our results indicate that the SKA1 gene might be involved in the development of oral squamous cell carcinoma and might predict its prognosis. SKA1 is expected to be a new molecular target for oral squamous cell carcinoma.

Knockdown of ectodysplasin-A receptor-associated adaptor protein exerts a tumor-suppressive effect in tongue squamous cell carcinoma cells

Tongue squamous cell carcinoma (TSCC) is a common malignancy in oral cancer with a high mortality and morbidity. The ectodysplasin-A receptor-associated adaptor protein (EDARADD) is a death domain-containing adaptor protein that interacts with the TNF family ligand ectodysplasin A receptor. It is known that EDARADD has an effect on the development of ectodermal derivative tissues, such as hair and teeth. EDARADD expression is also associated with the development of melanoma. However, the role of EDARADD in TSCC remains unknown. The aim of the present investigation was to explore whether EDARADD plays a role in the biological function of TSCC. Immunohistochemistry was used to measure the expression of EDARADD in TSCC tissues and adjacent normal tissue. EDARADD was knocked down in a TSCC cell line in vitro using a specific lentivirus. The expression level of the EDARADD gene and the efficacy of gene knockdown were evaluated by reverse transcription-quantitative PCR, while EDARADD protein expression and the expression levels of Bcl-2, MYC and NF-κBp65 were determined by western blotting. Additionally, MTT assays, colony formation assays and apoptosis assays were carried out to examine the effect of EDARADD knockdown on the TSCC cells. A previous study showed that the majority of the TSCC tissues that were tested had high EDARADD expression. The expression of EDARADD both at mRNA and protein levels was significantly lower (P<0.01) after the gene was knocked down in the CAL27 cells compared with the level in control cells. Downregulation of EDARADD expression inhibited colony formation and proliferation and induced apoptosis of CAL27 cells when compared to control cells (P<0.01). Taken together, these results suggested that EDARADD may be actively involved in the progression of TSCC and that EDARADD may be a novel therapeutic target for the treatment of TSCC.

Computational assessment of SKA1 as a potential cancer biomarker

Background

Spindle and kinetochore associated complex subunit 1 (SKA1) is an essential component of SKA complex, which is required for the proper formation of kinetochore–microtubule attachment and timely mitotic progression. The aim of this study is to perform detailed analyses of SKA1 genomic and expression alterations in cancers and to assess SKA1 as a biomarker for predicting human cancers and patient prognosis.

Materials and methods

Missense mutations from human cancers were extracted, deleterious missense mutations were predicted and shown on 3D SKA1 protein. SKA1 expression and the effect of SKA1 expression on patient survival were investigated in human cancers.

Results and discussion

Most of the predicted deleterious mutations were detected on microtubule-binding domain of SKA1, suggesting mutations on microtubule-binding domain might be more relevant in human cancers. High SKA1 expression was detected in various cancers. In addition, patients with high SKA1 expression showed poor overall survival compared to patients with low SKA1 expression in breast, lung and gastric cancers.

Conclusion

These results suggest that high SKA1 expression might be a prognostic and predictive biomarker for several cancers and mainly mutations in the microtubule-binding domain of SKA1 might have a deleterious effect for SKA1.

SKA1 overexpression is associated with poor prognosis in hepatocellular carcinoma

BACKGROUND

SKA1, an important mitosis protein, has been indicated in the initiation and progression of several malignancies. However, its clinical significance in hepatocellular carcinoma (HCC) remain to be elucidated.

METHODS

mRNA expression of SKA1 was examined in 126 HCC and paired non-neoplastic tissues using real-time PCR and validated in The Cancer Genome Atlas (TCGA) database. SKA1 protein expression was detected using immunohistochemistry in the 126 HCC tissues and its associations with clinicopathological parameters and prognosis were analyzed. Hierarchical cluster analysis and gene set enrichment analysis (GSEA) were performed in selected Gene Expression Omnibus data sets.

RESULTS

SKA1 mRNA expression was significantly elevated in HCC tissues from both local hospital and TCGA database. Immunohistochemistry revealed that increased SKA1 expression was present in 65 of the 126 cases and was significantly associated with higher serum alpha-fetoprotein concentration, larger tumor size and higher TNM stage. Patients with positive SKA1 expression showed significantly worse overall and relapse-free survival. Multivariate Cox regression analysis revealed that SKA1 was an independent predictor of patient prognosis. Gene expression profiling analysis of public data showed that high-SKA1 expression HCC tissues had similar gene expression profiles with fetal liver tissues. Moreover, GSEA showed that genes up-regulated in high SKA1 HCC subgroup were significantly enriched in cell cycle pathway, while genes down-regulated were significantly enriched in apoptosis pathway.

CONCLUSIONS

Our findings indicate that the oncofetal gene SKA1 might be involved in the progression of the HCC and could serve as a prognostic marker for HCC.

High expression of spindle and kinetochore- associated protein 1 predicts early recurrence and progression of non-muscle invasive bladder cancer

BACKGROUND

Spindle and kinetochore-associated protein 1 (SKA1) is a component of SKA, which is essential for proper chromosome segregation. Recently, SKA1 was found to be over-expressed in several types of human cancers. However, reports on the relationship between SKA1 expression and the prognosis of bladder cancer, in particular, are lacking.

OBJECTIVES

To clarify the clinical significance of SKA1 as a prognostic biomarker for early recurrence and progression of patients with non-muscle invasive bladder cancer (NMIBC).

METHODS

The differential expression levels of SKA1 of 148 NMIBC tissues were determined by immunohistochemical staining. Quantitative real-time PCR and western blot analysis were further performed to confirm the immunohistochemistry results. Recurrence and progression free interval were assessed by Kaplan-Meier method and differences between groups calculated by log-rank statistics. The prognostic value of SKA1 for early recurrence and progression was analyzed by multivariate Cox proportional hazard regression models.

RESULTS

SKA1 expression was significantly different in various NMIBC tissues. Kaplan-Meier analysis revealed that patients with high SKA1 expression showed high early recurrence (p< 0.001) and progression (p< 0.05) rates. Although univariate Cox regression analysis revealed that several other factors had an impact on recurrence and progression, upon multivariate analysis, high SKA1expression was the only independent predictor for early recurrence (hazards ratio [HR], 0.246; 95% confidence interval [CI], 0.131-0.461; p= 0.000) and progression (HR, 0.194; 95% CI, 0.052-0.715; p= 0.014).

CONCLUSIONS

High SKA1 expression is associated with early recurrence and progression in patients with NMIBC, indicating SKA1 may serve as a promising prognostic biomarker for this disease.

The stress response HPA-axis hormone, glucocorticoid, reduces cellular SKA complex gene expression

The Spindle- and Kinetochore-Associated (SKA) complex has been proven to be involved in many human mental behavioral disorders. Glucocorticoid, a hypothalamic-pituitary-adrenal (HPA) axis hormone, is a critical mediator of stress response in neurons. However, the underlying mechanisms of glucocorticoid's effects on human neuronal cells remain unclear. This study demonstrates that increased extracellular glucocorticoid levels significantly reduce neuronal cell SKA complex genes' expression levels, followed by altered neuronal cell viability and neurite development. The results suggest that the abnormality of this HPA-axis hormone could impact the neuronal cell functions through the alternation of SKA complex functions, which might induce cell death.

Targeting mitotic pathways for endocrine-related cancer therapeutics

A colossal amount of basic research over the past few decades has provided unprecedented insights into the highly complex process of cell division. There is an ever-expanding catalog of proteins that orchestrate, participate and coordinate in the exquisite processes of spindle formation, chromosome dynamics and the formation and regulation of kinetochore microtubule attachments. Use of classical microtubule poisons has still been widely and often successfully used to combat a variety of cancers, but their non-selective interference in other crucial physiologic processes necessitate the identification of novel druggable components specific to the cell cycle/division pathway. Considering cell cycle deregulation, unscheduled proliferation, genomic instability and chromosomal instability as a hallmark of tumor cells, there lies an enormous untapped terrain that needs to be unearthed before a drug can pave its way from bench to bedside. This review attempts to systematically summarize the advances made in this context so far with an emphasis on endocrine-related cancers and the avenues for future progress to target mitotic mechanisms in an effort to combat these dreadful cancers.

Regulation of spindle and kinetochore-associated protein 1 by antitumor miR-10a-5p in renal cell carcinoma

Analysis of our original microRNA (miRNA) expression signature of patients with advanced renal cell carcinoma (RCC) showed that microRNA‐10a‐5p (miR‐10a‐5p) was significantly downregulated in RCC specimens. The aims of the present study were to investigate the antitumor roles of miR‐10a‐5p and the novel cancer networks regulated by this miRNA in RCC cells. Downregulation of miR‐10a‐5p was confirmed in RCC tissues and RCC tissues from patients treated with tyrosine kinase inhibitors (TKI). Ectopic expression of miR‐10a‐5p in RCC cell lines (786‐O and A498 cells) inhibited cancer cell migration and invasion. Spindle and kinetochore‐associated protein 1 (SKA1) was identified as an antitumor miR‐10a‐5p target by genome‐based approaches, and direct regulation was validated by luciferase reporter assays. Knockdown of SKA1 inhibited cancer cell migration and invasion in RCC cells. Overexpression of SKA1 was observed in RCC tissues and TKI‐treated RCC tissues. Moreover, analysis of The Cancer Genome Atlas database demonstrated that low expression of miR‐10a‐5p and high expression of SKA1 were significantly associated with overall survival in patients with RCC. These findings showed that downregulation of miR‐10a‐5p and overexpression of the SKA1 axis were highly involved in RCC pathogenesis and resistance to TKI treatment in RCC.

Overexpression of spindle and kinetochore-associated protein 1 contributes to the progression of prostate cancer

Spindle and kinetochore-associated protein 1 is a microtubule-binding subcomplex of the outer kinetochore that is essential for proper chromosome segregation. Recently, spindle and kinetochore-associated protein 1 has been highlighted as a biomarker in various cancers; however, the precise role of spindle and kinetochore-associated protein 1 in prostate cancer remains unknown. This study aims to evaluate whether spindle and kinetochore-associated protein 1 affects the biological behaviors of prostate cancer. We investigated the expression of spindle and kinetochore-associated protein 1 in a series of prostate cancer tissues as well as in a panel of prostate cancer cell lines. Cell proliferation, migration, and invasion were evaluated in spindle and kinetochore-associated protein 1 knockdown prostate cancer cell lines by MTT and Transwell assays. Our results showed that the expression of spindle and kinetochore-associated protein 1 was remarkably upregulated in prostate cancer at both messenger RNA and protein levels compared with non-cancerous tissue. Knockdown of spindle and kinetochore-associated protein 1 repressed the ability of cell proliferation, migration, and invasion of prostate cancer cells. Moreover, inhibition of spindle and kinetochore-associated protein 1 could inhibit the activity of AKT and ERK pathway. In conclusion, our findings suggest that spindle and kinetochore-associated protein 1 could serve as a potential therapeutic target in prostate cancer patients.

SKA1 regulates the metastasis and cisplatin resistance of non-small cell lung cancer

Currently, chemotherapy with platinum-based drugs including cisplatin is the most effective therapy for the treatment of non-small cell lung carcinoma (NSCLC). However, the efficacy of chemotherapy is limited due to commonly developed drug resistance. Spindle and kinetochore-associated complex subunit 1 (SKA1) is part of a complex essential for stabilizing the attachment of spindle microtubules to kinetochores and for maintaining the metaphase plate during mitosis. In the present study, we aimed to investigate the role of SKA1 in the process of metastasis and drug resistance of NSCLC. We completed a series of experiments to investigate the function of SKA1 in NSCLC metastasis and drug resistance including qRT-PCR, immunohistochemistry and western blotting, as well as MTT, BrdU, wounded healing, Transwell and gelatin zymography assays. We demonstrated that the expression levels of SKA1 were elevated in NSCLC and were correlated with cancer progression and malignancy. We also reported that SKA1 positively regulated the proliferation and metastatic ability of NSCLC cells. In addition, we determined that SKA1 contributed to cisplatin resistance in NSCLC cells by protecting these cells from cisplatin-induced cell apoptosis. SKA1 also appeared to regulate the ERK1/2 and the Akt-mediated signaling pathways in NSCLC cells. SKA1 is required for metastasis and cisplatin resistance of non-small cell lung cancer.

Expression of Spindle and Kinetochore-Associated Protein 1 Is Associated with Poor Prognosis in Papillary Thyroid Carcinoma

AIM

Spindle and kinetochore-associated protein 1 (SKA1) is one subtype of SKA, whose protein can make spindle microtubules attach steadily to the kinetochore in the middle of mitosis. At present, there are fewer researches on the relationship between SKA1 expression and tumor development.

METHODS

In this study, immunohistochemical analysis was used to determine the expression of SKA1 in papillary thyroid carcinoma (PTC) and adjacent tissues. We used quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot analysis to further verify the results.

RESULTS

We found that SKA1 expression was significantly higher in PTC tissues than normal adjacent tissues (P < 0.05). There existed a significant correlation among a higher SKA1 expression, including lymphoid node (P = 0.005), clinical stage (P = 0.015), and extrathyroid invasion (P = 0.004). Survival analysis showed high SKA1 expression in PTC patients more likely to relapse after surgery.

CONCLUSION

High SKA1 expression is predictive of poor prognosis of PTC, implying that SKA1 may be a promising new target for targeted therapies for PTC.