Relationship between CacyBP/SIP expression and prognosis in astrocytoma

Downregulation of CacyBP by CRISPR/dCas9-KRAB Prevents Bladder Cancer Progression

Bladder cancer (BCa) is a leading cause of cancer-related death in the world. CacyBP is initially described as a binding partner of calcyclin and has been shown to be involved in a wide range of cellular processes, including cell differentiation, proliferation, protein ubiquitination, cytoskeletal dynamics and tumorigenesis. In the present study, we found that CacyBP expression was significantly upregulated in BCa tissues compared with adjacent normal tissues. Moreover, its expression was negatively correlated with overall survival time. Secondly, CacyBP had higher expressions in BCa cell lines than normal urothelial cells which was consistent with the results of BCa tissues. Finally, knockdown of CacyBP by CRIPSR-dCas9-KRAB in T24 and 5,637 BCa cells inhibited cell proliferation and migration by CCK-8 assay and scratch assay, and promoted apoptosis by caspase-3/ELISA. These data elucidate that CacyBP is an important oncogene contributing to malignant behavior of BCa and provide a potentially molecular target for treatment of BCa.

Bioinformatic analysis of Cacybp-associated proteins using human glioma databases

The ubiquitin-proteasome system is the primary cellular pathway for protein degradation, mediating 80% of intracellular protein degradation. Because of the widespread presence of ubiquitin-modified protein substrates, ubiquitination can regulate a variety of cellular activities including cell proliferation, apoptosis, autophagy, endocytosis, DNA damage repair, and immune responses. With the continuous generation of genomics data in recent years it has become particularly important to analyze these data effectively and reasonably. Cacybp forms a complex with the E3 ubiquitinated ligase Siah1 to participate in ubiquitination. We analyzed Cacybp-associated genes using the Gene Expression Omnibus (GEO) and CGGA (Chinese Glioma Genome Atlas) databases and identified 121 differentially expressed genes (DEGs), of which 46 were downregulated and 75 were upregulated. The biological processes, molecular functions, and protein-protein interaction (PPI) network of differential genes were analyzed by Cytoscape software and STRING software. We found no difference in Cacybp expression among different grades of gliomas and there was no significant association between the expression level of Cacybp and the prognosis of patients with glioma in LGG and GBM. © 2019 IUBMB Life, 1-8, 2019.

Transcriptional regulation of CacyBP/SIP gene and the influence of increased CacyBP/SIP level on gene expression pattern in colorectal cancer HCT116 cells

The CacyBP/SIP protein is expressed at a particularly high level in brain, spleen, and various tumors. In this work, we have studied transcriptional regulation of the CacyBP/SIP gene and the influence of increased CacyBP/SIP level on gene expression in colorectal cancer HCT116 cells. We have shown that E2F1, EGR1, and CREB transcription factors bind to the CacyBP/SIP gene promoter and stimulate transcription of CacyBP/SIP gene. The role of CREB was further confirmed by the observation that forskolin, a strong activator of CREB phosphorylation/activity, increased CacyBP/SIP gene promoter activity. Moreover, we have shown that CREB dominant negative mutants, CREB133 and KCREB, inhibits CacyBP/SIP promoter activity. To check the biological significance of increased CacyBP/SIP expression/level we have applied RNA microarray analysis and have found that upregulation of CacyBP/SIP entails changes in mRNA level of many genes involved, among others, in immune processes. © 2017 IUBMB Life, 70(1):50-59, 2018.

Molecular patterns of diffuse and nodular parathyroid hyperplasia in long-term hemodialysis

Secondary hyperparathyroidism is a well-known complication of end-stage renal disease (ESRD). Both nodular and diffuse parathyroid hyperplasia occur in ESRD patients. However, their distinct molecular mechanisms remain poorly understood. Parathyroid tissue obtained from ESRD patients who had undergone parathyroidectomy was used for Illumina transcriptome screening and subsequently for discriminatory gene analysis, pathway mapping, and gene annotation enrichment analysis. Results were further validated using quantitative RT-PCR on the independent larger cohort. Microarray screening proved homogeneity of gene transcripts in hemodialysis patients compared with the transplant cohort and primary hyperparathyroidism; therefore, further experiments were performed in hemodialysis patients only. Enrichment analysis conducted on 485 differentially expressed genes between nodular and diffuse parathyroid hyperplasia revealed highly significant differences in Gene Ontology terms and the Kyoto Encyclopedia of Genes and Genomes database in ribosome structure (P = 3.70 × 10^-18). Next, quantitative RT-PCR validation of the top differently expressed genes from microarray analysis proved higher expression of RAN guanine nucleotide release factor (RANGRF; P < 0.001), calcyclin-binding protein (CACYBP; P < 0.05), and exocyst complex component 8 (EXOC8; P < 0.05) and lower expression of peptidylprolyl cis/trans-isomerase and NIMA-interacting 1 (PIN1; P < 0.01) mRNA in nodular hyperplasia. Multivariate analysis revealed higher RANGRF and lower PIN1 expression along with parathyroid weight to be associated with nodular hyperplasia. In conclusion, our study suggests the RANGRF transcript, which controls RNA metabolism, to be likely involved in pathways associated with the switch to nodular parathyroid growth. This transcript, along with PIN1 transcript, which influences parathyroid hormone secretion, may represent new therapeutical targets to cure secondary hyperparathyroidism.

The potential role of CacyBP/SIP in tumorigenesis

Calcyclin-binding protein/Siah-1-interacting protein (CacyBP/SIP) was initially described as a binding partner of S100A6 in the Ehrlich ascites tumor cells and later as a Siah-1-interacting protein. This 30 kDa protein includes three domains and is involved in cell proliferation, differentiation, cytoskeletal rearrangement, and transcriptional regulation via binding to various proteins. Studies have also shown that the CacyBP/SIP is a critical protein in tumorigenesis. But, its promotion or suppression of cancer progression may depend on the cell type. In this review, the biological characteristics and target proteins of CacyBP/SIP have been described. Moreover, the exact role of CacyBP/SIP in various cancers is discussed.

CacyBP/SIP--Structure and variety of functions

BACKGROUND

CacyBP/SIP (Calcyclin-Binding Protein and Siah-1 Interacting Protein) is a small modular protein implicated in a wide range of cellular processes. It is expressed in different tissues of mammals but homologs are also found in some lower organisms. In mammals, a high level of CacyBP/SIP is present in tumor cells and in neurons. CacyBP/SIP binds several target proteins such as members of the S100 family, components of a ubiquitin ligase complex, and cytoskeletal proteins.

SCOPE OF REVIEW

CacyBP/SIP has been shown to be involved in protein de-phosphorylation, ubiquitination, cytoskeletal dynamics, regulation of gene expression, cell proliferation, differentiation, and tumorigenesis. This review focuses on very recent reports on CacyBP/SIP structure and function in these important cellular processes.

MAJOR CONCLUSIONS

CacyBP/SIP is a multi-domain and multi-functional protein. Altered levels of CacyBP/SIP in several cancers implicate its involvement in the maintenance of cell homeostasis. Changes in CacyBP/SIP subcellular localization in neurons of AD brains suggest that this protein is strongly linked to neurodegenerative diseases. Elucidation of CacyBP/SIP structure and cellular function is leading to greater understanding of its role in normal physiology and disease pathologies.

GENERAL SIGNIFICANCE

The available results suggest that CacyBP/SIP is a key player in multiple biological processes. Detailed characterization of the physical, biochemical and biological properties of CacyBP/SIP will provide better insight into the regulation of its diverse functions in vivo, and given the association with specific diseases, will help clarify the potential of therapeutic targeting of this protein.

Decreased expression of microRNA-107 predicts poorer prognosis in glioma

The expression level of microRNA-107 (miR-107) has been proved to be decreased in many human malignant cancers. Especially in glioma, accumulating evidence indicates that miR-107 may play important parts in cell proliferation, apoptosis, and invasion in glioma. However, its clinical significance in glioma has not been investigated. This study aims at investigating the relationship between miR-107 expression level and clinical significance and analyzing its value of miR-107 in valuing the prognosis of glioma patients. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to measure the expression of miR-107 in 80 glioma and 17 normal brain tissues. The results showed the miR-107 expression level in glioma tissues was significantly lower than those in normal brain tissues (p < 0.001). The decreased expression of miR-107 in glioma was positively associated with high WHO grade (p < 0.001), low Karnofsky performance score (KPS) (p < 0.001), and large tumor size (p < 0.001) and had a significant impact on overall survival (OS) (p < 0.001) and progression-free survival (PFS) (p < 0.001) according to Kaplan-Meier survival with log-rank test. Finally, Cox regression analyses showed that low miR-107 expression (p < 0.001) might be an independent prognostic parameter to predict poor prognosis. In conclusion, it is the first data to prove that expression level of miR-107 may be a novel and valuable prognostic factor in glioma.

Decreased expression of microRNA-206 correlates with poor clinical outcome in patients with malignant astrocytomas

MicroRNA-206 (miR-206) has been proved to function as a tumor suppressor in several types of human malignant cancers. More recently, it has been demonstrated that the ectopic expression of miR-206 significantly inhibited the proliferation and promoted apoptosis at the early stages in glioma cell U343. In order to investigate the clinical significance of miR-206 expression in human astrocytoma, quantitative real-time polymerase chain reaction (qRT-PCR) analysis was used to characterize the expression patterns of miR-206 in 108 astrocytoma and 20 normal brain tissues. As the results, the expression levels of miR-206 in astrocytoma tissues were significantly lower than those in normal brain tissues (P < 0.001). Additionally, the decreased expression of miR-206 in astrocytoma was significantly associated with advanced pathological grade (P = 0.008), low Karnofsky performance score (KPS, P = 0.02), and large tumor size (P = 0.01). Moreover, Kaplan-Meier survival and Cox regression analyses showed that low miR-206 expression (P < 0.001) and advanced pathological grade (P = 0.02) were independent factors predicting poor prognosis for astrocytomas. In conclusion, this is the first report of the differential expression of miR-206 in human astrocytoma tissues. MiR-206 could be a valuable marker of astrocytoma progression and low miR-206 expression is associated with poor overall survival in patients with malignant astrocytomas.