Spindle and Kinetochore-Associated Complex is Associated With Poor Prognosis in Adrenocortical Carcinoma

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.

In vitro and in vivo induction of ochratoxin A exposure-related micronucleus formation in rat proximal tubular epithelial cells and expression profiling of chromosomal instability-related genes

Ochratoxin A (OTA) is a renal carcinogen in rats, and repeated administration induces karyomegaly in proximal tubular epithelial cells (PTECs) of the outer stripe of the outer medulla (OSOM) before inducing proliferative lesions. To investigate whether OTA induces micronuclei (MN) in PTECs, we performed an in vitro MN assay using rat renal NRK-52E PTECs after treatment for ≤21 days, and an in vivo OSOM MN assay in rats treated with OTA, other renal carcinogens, or non-carcinogenic renal toxicants for 4 or 13 weeks. The in vitro assay revealed an increased frequency of micronucleated cells from the acceptable dose level for cell viability, even after 21 days of treatment. The in vivo assay also revealed a dose- and treatment period-dependent increase in PTECs with γ-H2AX+ MN. OTA-specific gene expression profiling by OSOM RNA sequencing after week 13 revealed the altered expression of genes related to microtubule-kinetochore binding, the kinesin superfamily, centriole assembly, DNA damage repair, and cell cycle regulation. MN formation was also observed with other renal carcinogens that induce karyomegaly similarly to OTA. These results imply that γ-H2AX+ MN formation by OTA treatment is related to the induction of chromosomal instability accompanying karyomegaly formation before proliferative lesions form, providing a new insight into the carcinogenic mechanism that may be relevant to humans.

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.

Prognostic and immunological values of SKA3 for overall survival in lung adenocarcinoma and its RNA binding protein involved mechanisms

This article aimed to investigate the correlations among SKA3 expression and prognosis, clinical relevance, tumor immunity, and RNA-binding protein (RBP)-involved mechanisms for overall survival (OS) in lung adenocarcinoma (LUAD). To explore the SKA3 expression level in LUAD by analyzing the genomic data as well as related clinical characteristics from the database of TCGA. Nomogram and gene set enrichment analysis (GSEA) were applied, respectively, to evaluate the performance of SKA3 in LUAD. Correlations between SKA3 and immunity and RBP-involved mechanisms were also performed. SKA3 had a higher expression level in LUAD samples than in adjacent normal lung samples, with shorter survival times in the high-SKA3-expressed LUAD subgroup (P < 0.05). qRT-PCR results remained consistent (P < 0.05). Uni-/multivariate Cox analyses revealed that SKA3 could have independent prognostic ability for LUAD (both P < 0.05). The nomogram model constructed with clinical pathological parameters and SKA3 expression levels predicted OS rates for LUAD and GSEA revealed SKA3-related pathways. In aspects of tumor immunity, SKA3 was significantly involved with tumor neoantigen burden, tumor mutational burden, immune cell pathways, and immune checkpoint inhibitor (ICI) molecules (all P < 0.05). The CellMiner database also found significant correlations between SKA3 and the antitumor drug sensitivity of chemotherapy, fenretinide, and PX-316. Besides, a total of nine LncRNA/RBP/SKA3 networks were revealed in LUAD for their RBP-involved mechanisms. SKA3 could serve as a potential biomarker for OS prognosis and immunotherapy in LUAD. LncRNA/RBP/SKA3 networks were identified in LUAD for their RBP-involved mechanisms, paving the way for further experimental verifications.

System analysis identifies UBE2C as a novel oncogene target for adrenocortical carcinoma

Ubiquitin Conjugating Enzyme 2C (UBE2C) is an emerging target gene for tumor progression. However, the tumorigenic effect and mechanism of UBE2C in adrenocortical carcinoma (ACC) remains unclear. Systematic investigation of the tumorigenic effect of UBE2C may help in understanding its prognostic value in adrenocortical carcinoma. First, we exploited the intersection on DFS-related genes, OS-related genes, highly expressed genes in adrenocortical carcinoma as well as differentially expressed genes (DEGs) between tumor and normal, and then obtained 20 candidate genes. UBE2C was identified to be the most significant DEG between tumor and normal. It is confirmed that high expression of UBE2C was strongly associated with poor prognosis in patients with ACC by analyzing RNA-seq data of ACC obtained from the Cancer Genome Atlas (TCGA) database implemented by ACLBI Web-based Tools. UBE2C expression could also promote m6A modification and stemness in ACC. We found that UBE2C expression is positively associated with the expression of CDC20, CDK1, and CCNA2 using ACLBI Web-based Tools, indicated the hyperactive cell cycle progression present in ACC with high UBE2C expression. In addition, UBE2C knockdown could significantly inhibit the proliferation, migration, invasion, EMT of adrenocortical carcinoma cells as well as the cell cycle progression in vitro. Notably, pan-cancer analysis also identified UBE2C as an oncogene in various tumors. Taken together, UBE2C was strongly associated with poor prognosis of patients with ACC by promoting cell cycle progression and EMT. This study provides a new theoretical basis for the development of UBE2C as a molecular target for the treatment of ACC.

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.