ZIC5 facilitates the growth of hepatocellular carcinoma through activating Wnt/β-catenin pathway

Research progress of ZIC5 for tumor metastasis

The zinc finger protein of the cerebellum (ZIC) family comprises five members (ZIC1-5), homologous with the odd-paired (OPA) gene in Drosophila melanogila. These transcription factors contain five Cys2His zinc finger domains, constituting one of the most abundant transcription factor families in human cells. ZIC proteins significantly contribute to transcriptional regulation and chromatin remodeling. As a member of the ZIC family, ZIC5 is essential for animal growth and development. Numerous studies have investigated the connection between ZIC proteins and cancer as well as tumor metastases in recent years. Many studies have found that within tumor tissues, the transcription and translation processes increase the expression of ZIC5 which is linked to tumor aggressiveness. This review aims to provide an objective summary of the impact of ZIC5 on tumor metastasis and consider the potential application of ZIC5 targets in both tumor therapy and the early detection of cancer.

MicroRNA-101-3p inhibits nasopharyngeal carcinoma cell proliferation and cisplatin resistance through ZIC5 down-regulation by targeting SOX2

This study aims to explore the mechanism of microRNA (miR)-101-3p-mediated SOX2/ZIC5 axis in the progression of cisplatin resistance of nasopharyngeal carcinoma (NPC). ZIC5 expression was analyzed with a bioinformatics database and detected in NPC cell lines. Cisplatin-resistant cells (HNE-1/DDP and C666-1/DDP) were transfected with sh-ZIC5, sh-SOX2, sh-SOX2 + pcDNA3.1-ZIC5, or miR-101-3p Agomir + pcDNA3.1-SOX2. MiR-101-3p, SOX2, and ZIC5 expression was assessed after transfection, and cancer associated phenotypes were evaluated after cisplatin treatment. The potential relationships among miR-101-3p, SOX2, and ZIC5 were analyzed. A xenograft mouse model of NPC was established with HNE-1 cells stably transfected or not transfected with oe-ZIC5 and subjected to tail vein injection of miR-101-3p Agomir and intraperitoneal injection of cisplatin. Overexpression of ZIC5 was found in cisplatin-resistant NPC cells. Downregulating ZIC5 in NPC cells decreased cell viability, promoted apoptosis, and reduced cisplatin resistance. SOX2 had a binding site on ZIC5, and SOX2 promoted proliferation, migration, and cisplatin resistance and inhibited cell apoptosis by up-regulating ZIC5. Mechanistically, miR-101-3p was decreased in cisplatin-resistant NPC cells and negatively targeted SOX2. Overexpression of miR-101-3p inhibited tumor growth and cisplatin resistance in xenograft mouse model, which was reversed by ZIC5 overexpression. In conclusion, the miR-101-3p/SOX2/ZIC5 axis was implicated in cancer associated phenotypes and cisplatin resistance in NPC.

ZIC5 promotes aggressiveness and cancer stemness in cervical squamous cell carcinoma

BACKGROUND

Cervical cancer is one of the major malignancies causing morbidity and mortality in women in developing countries. ZIC5 has been found to be associated with a variety of cancers, yet the expression and molecular function of ZIC5 in cervical squamous cell carcinoma (CESC) is unknown.

METHODS

We examined the expression of ZIC5 in tumors and normal tissues of CESC patients using immunohistochemistry, immunoblotting and fluorescent quantitative PCR, and used statistical methods to explore its relationship with clinical manifestations. Next, we constructed ZIC5 knockdown and overexpression CESC cell lines to observe the effect of ZIC5 on the proliferation and metastasis of CESC cells. Finally, we applied a nude mouse xenograft tumor model to observe the effect of ZIC5 on tumorigenesis in vivo.

RESULTS

Our results showed that the expression of ZIC5 was higher in cancer tissues than in normal tissues. Prognostic analysis showed that ZIC5 expression level was an independent prognostic factor in CESC patients, and the results of Transwell, CCK-8 and wound healing assays confirmed that overexpression of ZIC5 could promote the proliferation and migration of CESC cells. A nude mouse xenograft tumor model showed that knockdown of ZIC5 inhibited tumor growth in vivo. Database, immunoblotting assay and in vitro sphere-forming assay confirmed that ZIC5 could promote the stemness of CESC cells.

CONCLUSION

ZIC5 is a factor that indicates a poor prognosis of CESC patients and promotes stemness in CESC cells. ZIC5 may be a potential biomarker and therapeutic target for CESC patients.

Patulin and LL‐Z1640 ‐2 induce apoptosis of cancer cells by decreasing endogenous protein levels of Zic family member 5

Zic family member 5 (ZIC5) is a transcription factor that promotes the survival of several cancer cell types. As ZIC5 is expressed at minimal levels in normal human adult tissues, it is a potential therapeutic target. In this study, we screened a chemical library containing 3398 compounds that includes pre‐existing drugs and compounds with known effects to identify ZIC5 inhibitors. In the first screening, 18 hit compounds decreased GFP intensity in melanoma A375 cells overexpressing GFP‐tagged ZIC5. In the second screening, five compounds that attenuated ZIC5 protein levels in A375 cells were identified. Among them, LL‐Z1640‐2 and patulin selectively induced apoptosis in melanoma cells expressing ZIC5, while only inducing very low levels of apoptosis in normal human melanocytes, which have no detectable ZIC5 expression. LL‐Z1640‐2 and patulin also induced apoptosis in BRAF inhibitor‐resistant melanoma, pancreatic cancer, cholangiocarcinoma and colorectal cancer cells. LL‐Z1640‐2‐ and patulin‐mediated suppression of melanoma proliferation were rescued by ZIC5 overexpression. These results suggest that LL‐Z1640‐2 and patulin are promising compounds that decrease ZIC5 expression to induce apoptosis in cancer cells.

AR-regulated ZIC5 contributes to the aggressiveness of prostate cancer

The mechanisms by which prostate cancer (PCa) progresses to the aggressive castration-resistant stage remain uncertain. Zinc finger of the cerebellum 5 (ZIC5), a transcription factor belonging to the ZIC family, is involved in the pathology of various cancers. However, the potential effect of ZIC5 on PCa malignant progression has not been fully defined. Here, we show that ZIC5 is upregulated in PCa, particularly in metastatic lesions, in positive association with poor prognosis. Genetic inhibition of ZIC5 in PCa cells obviously attenuated invasion and metastasis and blunted the oncogenic properties of colony formation. Mechanistically, ZIC5 functioned as a transcription factor to promote TWIST1-mediated EMT progression or as a cofactor to strengthen the β-catenin-TCF4 association and stimulate Wnt/β-catenin signaling. Importantly, ZIC5 and the androgen receptor (AR) form a positive feed-forward loop to mutually stimulate each other’s expression. AR, in cooperation with its steroid receptor coactivator 3 (SRC-3), increased ZIC5 expression through binding to the miR-27b-3p promoter and repressing miR-27b-3p transcription. In turn, ZIC5 potentiated AR, AR-V7, and AR targets’ expression. Besides, ZIC5 inhibition reduced AR and AR-V7 protein expression and enhanced the sensitivity of PCa to enzalutamide (Enz) treatment, both in vitro and in vivo. These findings indicate that the reciprocal activation between AR and ZIC5 promotes metastasis and Enz resistance of PCa and suggest the therapeutic value of cotargeting ZIC5 and AR for the treatment of advanced PCa.

Zic family member 5 promotes survival in human pancreatic cancer and cholangiocarcinoma cells

Pancreatic ductal adenocarcinoma (PDAC) and cholangiocarcinoma (CCA) are malignant tumors with poor prognosis because of the limited effectiveness of traditional chemotherapy and few effective molecular therapeutic agents. Here, we determined the essential roles of Zic family member 5 (ZIC5) in the survival of PDAC and CCA cells. The results showed that ZIC5 is strongly expressed in PDAC and CCA tissues, while ZIC5 expression is barely observed in most normal human adult tissues. Furthermore, ZIC5 expression is related to poor prognosis of patients with PDAC. ZIC5 knockdown via small interfering RNA decreased the phosphorylation of signal transducer and activator of transcription 3 (STAT3), a protein that is associated with PDAC and CCA aggressiveness. However, ZIC5 knockdown induced cell death regardless of STAT3 activation, which is promoted by interleukin (IL) −6, a factor associated with inflammation. Furthermore, knockdown of ZIC5 in PDAC and CCA cells additively or synergistically induced apoptosis with the anti-cancer drug gemcitabine. Thus, ZIC5 constitutes a potential therapeutic target for the treatment of PDAC and CCA.

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ZIC5 is expressed in PDAC and CCA, while barely observed in normal adult tissues.

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ZIC5 expression is related to poor prognosis of patients with PDAC.

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ZIC5 knockdown induces apoptosis in several PDAC and CCA cell lines.

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Knockdown of ZIC5 additively or synergistically induces apoptosis with gemcitabine.

CAPRIN1 Enhances Chemoresistance and Glycolysis in Laryngeal Squamous Cell Carcinoma via Regulation of ZIC5

Background

Cytoplasmic activation/proliferation-associated protein-1 (CAPRIN1) plays an important role in carcinogenesis, whereas its role in laryngeal squamous cell carcinoma remains unclear. This study was designed to investigate the roles of CAPRIN1 in glycolysis and chemoresistance and its underlying mechanisms in laryngeal squamous cell carcinoma.

Methods

Cell viability was evaluated by using CCK-8 and colony formation assays. qRT-PCR, Western blotting, and immunohistochemistry were used to determine the expressions of target genes. Gene knockdown and overexpression cell lines were constructed by performing transfection of siRNAs and plasmids, respectively. Luciferase reporter assay, RNA pull-down, and RNA immunoprecipitation assays were applied to evaluate the RNA-protein interactions. The Kaplan-Meier analysis was performed to evaluate the relationship between gene expression and overall survival rate.

Results

An elevation of CAPRIN1 was identified to be associated with chemoresistance and poor prognosis in patients with laryngeal cancer. The increase of CAPRIN1 promoted glycolysis and chemoresistance, whereas the knockdown of CAPRIN1 inhibited glycolysis and chemoresistance in laryngeal cancer cells. The underlying mechanistic investigation revealed that CAPRIN1 promoted glycolysis and chemoresistance of laryngeal cancer cells by the regulation of Zic Family Member 5 (ZIC5).

Conclusion

CAPRIN1 promoted laryngeal squamous cell carcinoma glycolysis and chemoresistance by the regulation of ZIC5.

The Transcription Factor FEZF1, a Direct Target of EWSR1-FLI1 in Ewing Sarcoma Cells, Regulates the Expression of Neural-Specific Genes

Ewing sarcoma is a rare pediatric tumor characterized by chromosomal translocations that give rise to aberrant chimeric transcription factors (e.g., EWSR1-FLI1). EWSR1-FLI1 promotes a specific cellular transcriptional program. Therefore, the study of EWSR1-FLI1 target genes is important to identify critical pathways involved in Ewing sarcoma tumorigenesis. In this work, we focused on the transcription factors regulated by EWSR1-FLI1 in Ewing sarcoma. Transcriptomic analysis of the Ewing sarcoma cell line A673 indicated that one of the genes more strongly upregulated by EWSR1-FLI1 was FEZF1 (FEZ family zinc finger protein 1), a transcriptional repressor involved in neural cell identity. The functional characterization of FEZF1 was performed in three Ewing sarcoma cell lines (A673, SK-N-MC, SK-ES-1) through an shRNA-directed silencing approach. FEZF1 knockdown inhibited clonogenicity and cell proliferation. Finally, the analysis of the FEZF1-dependent expression profile in A673 cells showed several neural genes regulated by FEZF1 and concomitantly regulated by EWSR1-FLI1. In summary, FEZF1 is transcriptionally regulated by EWSR1-FLI1 in Ewing sarcoma cells and is involved in the regulation of neural-specific genes, which could explain the neural-like phenotype observed in several Ewing sarcoma tumors and cell lines.

Wnt Signaling Pathway Is among the Drivers of Liver Metastasis

Liver metastasis, originating either from a primary liver or other cancer types, represent a large cancer-related burden. Therefore, studies that add to better understanding of its molecular basis are needed. Herein, the role of the Wnt signaling pathway in liver metastasis is outlined. Its role in hepatocellular carcinoma (HCC) epithelial-mesenchymal transition (EMT), motility, migration, metastasis formation, and other steps of the metastatic cascade are presented. Additionally, the roles of the Wnt signaling pathway in the liver metastasis formation of colorectal, breast, gastric, lung, melanoma, pancreatic, and prostate cancer are explored. The special emphasis is given to the role of the Wnt signaling pathway in the communication between the many of the components of the primary and secondary cancer microenvironment that contribute to the metastatic outgrowth in the liver. The data presented herein are a review of the most recent publications and advances in the field that add to the idea that the Wnt pathway is among the drivers of liver metastasis and that its targeting could potentially relieve liver metastasis–related complications.

SP1-mediated upregulation of lncRNA SNHG4 functions as a ceRNA for miR-377 to facilitate prostate cancer progression through regulation of ZIC5

BACKGROUND/AIMS

Long noncoding RNAs (lncRNAs) have been demonstrated to serve distinct roles in human tumorigenesis. Previous studies have found that lncRNA small nucleolar RNA host gene 4 (SNHG4) was dysregulated in several tumors. However, the expression, clinical significances, and action mechanisms of SNHG4 in prostate cancer (PCa) are still unclear.

METHODS

Quantitative real-time polymerase chain reaction (qRT-PCR) was utilized to detect SNHG4 expression in tissue samples and PCa cells. Cell counting kit-8, 5-ethynyl-2'-deoxyuridine, clonogenic formation, wound-healing, and transwell invasion assays were, respectively, used to evaluate cell proliferation, colony formation ability, migration, and invasion. Flow cytometric analysis was applied to assess cell apoptosis. Chromatin immunoprecipitation assays were conducted to determine the binding between SP1 and SNHG4 promoter. Luciferase reporter assay, qRT-PCR, and western blot analysis were carried out to explore and confirm the interaction among SNHG4, miR-377, and ZIC5.

RESULTS

SNHG4 was highly expressed in PCa and its upregulation was induced by transcription factor SP1. The high levels of SNHG4 were distinctly associated with tumor stage, lymph node metastasis, and reduced overall survival of patients with PCa. SNHG4 knockdown inhibited the growth, migration, and invasion of PCa cells. In addition, miR-377 was a target of SNHG4 and ZIC5 was a target gene of miR-377 in PCa. SNHG4 promoted ZIC5-mediated growth and metastasis through modulating miR-377.

CONCLUSION

Our findings illuminate how SNHG4 formed a regulatory network to display a tumor-promotive effect in PCa and revealed that SNHG4 may be a novel therapeutic target and prognostic marker for patients with PCa.

S100A9 as a novel diagnostic and prognostic biomarker in human gastric cancer

Objective: The morbidity and mortality of gastric cancer (GC) is high, but there are lack of the biomarkers for early diagnosis and progression of GC. We aimed to identify a novel biomarker for the growth and progression of GC.Methods: The Cancer Genome Atlas (TCGA) database including 352 eligible patients was used to screen candidate genes related to the prognosis of GC. A proteomics analysis of Chinese Human Proteome Sketches (CHPS) including 84 eligible sample tissues was conducted to further identify candidate biomarkers. A series of in vitro assays were performed to investigate the functions of candidate proteins in GC. Next, to verify whether the candidate oncogene was associated with gastric carcinogenesis, we screened its expression levels using samples from 200 patients with chronic atrophic gastritis (CAG), intestinal metaplasia (IM), dysplasia, or GC and healthy controls.Results: According to the analyses of the TCGA database and CHPS, we found that S100A9 may be associated with the prognosis of GC. The results of proliferation, wound-healing and invasion assays, immunohistochemistry (IHC) and western blot showed that high levels of S100A9 in tissues were significantly associated with GC aggressiveness and a poor prognosis (p < .05). Furthermore, we found that the expression of S100A9 increased gradually during the process of gastric carcinogenesis (p < .05). The diagnostic sensitivity and specificity of S100A9 as a biomarker for early GC were 61.4% and 81.3%, respectively.Conclusions: This study reveals that S100A9 may be a novel biomarker for the early diagnosis and prognosis of GC patients.

KIF18B promotes hepatocellular carcinoma progression through activating Wnt/β-catenin-signaling pathway

This study aimed to investigate the functional roles of kinesin family member 18B (KIF18B) in hepatocellular carcinoma (HCC) development, as well as the related molecular mechanisms. Tissue specimens were collected from 105 patients with HCC, and the messenger RNA (mRNA) and protein levels of KIF18B were detected using quantitative real-time polymerase chain reaction and immunohistochemistry assays, respectively. The χ² test was performed to estimate the association of KIF18B with clinical characteristics of patients with HCC. Effects of KIF18B expression on biological behaviors of HCC cells were detected by clone formation, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, and transwell assays. The expression patterns of proteins were investigated using Western blot analysis. HCC tissues and cell lines showed significant upregulation of KIF18B at both mRNA and protein levels (p > .05, for all). Furthermore, the elevated KIF18B expression was positively correlated with the tumor-node-metastasis stage (p = .015) and lymph node metastasis (p = .007). Knockdown of KIF18B might suppress HCC cell clone formation, proliferation, migration, and invasion in vitro. Besides, the activity of Wnt/β-catenin pathway was also significantly inhibited after the KIF18B knockdown. However, the antitumor actions caused by KIF18B knockdown might be reversed by lithium chloride treatment, which was the inducer of Wnt/β-catenin-signaling pathway. KIF18B may serve as an oncogene in HCC through enhancing the activity of Wnt/β-catenin pathway.

Zic1 suppresses gastric cancer metastasis by regulating Wnt/β-catenin signaling and epithelial-mesenchymal transition

Gastric cancer (GC) patients with metastasis had limited treatment options and dismal outcome. We have previously reported the aberrant expression of Zic family member 1 (Zic1) in GC. However, the functional roles and underlying mechanism of Zic1 in GC metastasis remain unknown. Here, we demonstrate that lower expression of Zic1 was correlated with more lymph node metastasis and poor outcome of GC patients. Ectopic expression of Zic1 suppressed both lung metastasis and peritoneal tumor dissemination of GC in mice. The metastatic suppressing ability of Zic1 was mediated by regulating the process of cell invasion, adhesion and epithelial-mesenchymal transition (EMT). Mechanistically, Zic1 could downregulate Wnt targets including c-Myc and Cyclin D1 by inhibiting LEF transcriptional activity in GC cells. Notably, Zic1 was inversely related to the expression of Cyclin D1 in GC tissues tested. In addition, Zic1 could physically interact with β-catenin/transcription factor 4 (TCF4) and disrupt their complex formation, while not affecting β-catenin nuclear localization. Collectively, our study indicated that Zic1 suppressed GC metastasis through attenuating Wnt/β-catenin signaling and the EMT process. Our work may provide novel therapeutic strategies for the metastasis of GC.