SOX17 restrains proliferation and tumor formation by down-regulating activity of the Wnt/β-catenin signaling pathway via trans-suppressing β-catenin in cervical cancer

HECW1 restrains cervical cancer cell growth by promoting DVL1 ubiquitination and downregulating the activation of Wnt/β-catenin signaling

HECW1 belongs to ubiquitin ligase (E3) HECT family, and is found to be involved in tumorigenesis and tumor progression. However, the function of HECW1 in cervical cancer (CC) remains unknown. Clinical analysis showed that HECW1 is significantly decreased in CC tumor tissues. Ectopic expression of HECW1 suppressed cell growth, promoting cell cycle arrest and apoptosis in CC cells, while downregulation of HECW1 reversed these trends, impeded proliferation and accelerated cell cycle progression of CC cells. Overexpressing of HECW1 reduced mitochondrial membrane potential and the protein expression of voltage-dependent anion channel 1 (VDAC1). In addition, upregulation of HECW1 inhibited nuclear β-catenin accumulation, downregulated β-catenin/TCF/LEF-mediated transcriptional activity and the expression of downstream gene c-Myc, whereas inhibition of HECW1 received opposite results. Further results confirmed HECW1 affects the protein expression of dishevelled-1 (DVL1), a potent activator of Wnt/β-catenin, and inhibition of HECW1 inhibited the ubiquitination of DVL1, upregulating its expression. Inhibition of DVL1 restrained the promotion effect of HECW1 suppression on cell proliferation. In vivo experiments also verified that HECW1 suppression promoted the tumor formation of CC cells. Summary, we demonstrated that HECW1 inhibits CC cell proliferation and tumor formation by downregulating DVL1 induced Wnt/β-catenin signaling pathway activation.

Compound AC1Q3QWB upregulates CDKN1A and SOX17 by interrupting the HOTAIR-EZH2 interaction and enhances the efficacy of tazemetostat in endometrial cancer

Endometrial cancer (EC) is a common malignancy of the female reproductive system, with an escalating incidence. Recurrent/metastatic EC presents a poor prognosis. The interaction between the long non-coding RNA (lncRNA) HOTAIR and the polycomb repressive complex 2 (PRC2) induces abnormal silencing of tumor suppressor genes, exerting a pivotal role in tumorigenesis. We have previously discovered AC1Q3QWB (AQB), a small-molecule compound targeting HOTAIR-EZH2 interaction. In the present study, we unveil that AQB selectively hampers the interaction between HOTAIR and EZH2 within EC cells, thus reversing the epigenetic suppression of tumor suppressor genes. Furthermore, our findings demonstrate AQB's synergistic effect with tazemetostat (TAZ), an EZH2 inhibitor, significantly boosting the expression of CDKN1A and SOX17. This, in turn, induces cell cycle arrest and impedes EC cell proliferation, migration, and invasion. In vivo experiments further validate AQB's potential by enhancing TAZ's anti-tumor efficacy at lower doses. Our results advocate AQB, a recently discovered small-molecule inhibitor, as a promising agent against EC cells. When combined with TAZ, it offers a novel therapeutic strategy for EC treatment.

Upregulation of SOX9 promotes the self-renewal and tumorigenicity of cervical cancer through activating the Wnt/β-catenin signaling pathway

Sry-box9 (SOX9) maintains stem cell properties and plays crucial roles in many cancers. However, whether SOX9 is correlated with cervical cancer cell stemness and its detailed mechanism remains obscure. We studied the relationship between SOX9 and prognosis of cervical cancer through public database, and SOX9 was related to poor prognosis of cervical cancer. Elevated SOX9 expression enhanced the self-renewal properties and promotes tumorigenicity in cervical cancer. Overexpression of SOX9 could promote the expression of stem cell-related factors in cervical cancer cells and xenografts. Meanwhile, overexpression of SOX9 could also enhance the expressions of FZD10, β-catenin, and c-Myc in cervical cancer cells and xenografts, while inhibiting the expression of DDK1. The activation of Wnt pathway by chir-99 021 raised the tumor spheroid ability of SOX9 knockdown HeLa cells. In addition, SOX9 could transcriptional inhibit DKK1 and activate FZD10 and MYC by binding to their promoters to affect the Wnt/β-catenin pathway. These results demonstrated SOX9 regulated the self-renewal and tumorigenicity of cervical cancer through Wnt/β-catenin pathway by directly transcriptional activation of FZD10, MYC and transcriptional inhibition of DKK1.

Pan-cancer Analysis Reveals Cancer-dependent Expression of SOX17 and Associated Clinical Outcomes

BACKGROUND/AIM

SRY-box containing gene 17 (SOX17) plays a pivotal role in cancer onset and progression and is considered a potential target for cancer diagnosis and treatment. However, the expression pattern of SOX17 in cancer and its clinical relevance remains unknown. Here, we explored the relationship between the expression of SOX17 and drug response by examining SOX17 expression patterns across multiple cancer types.

MATERIALS AND METHODS

Single-cell and bulk RNA-seq analyses were used to explore the expression profile of SOX17. Analysis results were verified with qPCR and immunohistochemistry. Survival, drug response, and co-expression analyses were performed to illustrate its correlation with clinical outcomes.

RESULTS

The results revealed that abnormal expression of SOX17 is highly heterogenous across multiple cancer types, indicating that SOX17 manifests as a cancer type-dependent feature. Furthermore, the expression pattern of SOX17 is also associated with cancer prognosis in certain cancer types. Strong SOX17 expression correlates with the potency of small molecule drugs that affect PI3K/mTOR signaling. FGF18, a gene highly relevant to SOX17, is involved in the PI3K-AKT signaling pathway. Single-cell RNA-seq analysis demonstrated that SOX17 is mainly expressed in endothelial cells and barely expressed in other cells but spreads to other cell types during the development of ovarian cancer.

CONCLUSION

Our study revealed the expression pattern of SOX17 in pan-cancer through bulk and single-cell RNA-seq analyses and determined that SOX17 is related to the diagnosis, staging, and prognosis of some tumors. These findings have clinical implications and may help identify mechanistic pathways amenable to pharmacological interventions.

Cardio-oncology: Shared Genetic, Metabolic, and Pharmacologic Mechanism

PURPOSE OF REVIEW

The article aims to investigate the complex relationship between cancer and cardiovascular disease (CVD), with a focus on the effects of cancer treatment on cardiac health.

RECENT FINDINGS

Advances in cancer treatment have improved long-term survival rates, but CVD has emerged as a leading cause of morbidity and mortality in cancer patients. The interplay between cancer itself, treatment methods, homeostatic changes, and lifestyle modifications contributes to this comorbidity. Recent research in the field of cardio-oncology has revealed common genetic mutations, risk factors, and metabolic features associated with the co-occurrence of cancer and CVD. This article provides a comprehensive review of the latest research in cardio-oncology, including common genetic mutations, risk factors, and metabolic features, and explores the interactions between cancer treatment and CVD drugs, proposing novel approaches for the management of cancer and CVD.

Single-Cell Landscape Highlights Heterogenous Microenvironment, Novel Immune Reaction Patterns, Potential Biomarkers and Unique Therapeutic Strategies of Cervical Squamous Carcinoma, Human Papillomavirus-Associated (HPVA) and Non-HPVA Adenocarcinoma

Cervical adenocarcinomas (ADCs), including human papillomavirus (HPV)-associated (HPVA) and non-HPVA (NHPVA), though exhibiting a more malignant phenotype and poorer prognosis, are treated identically to squamous cell carcinoma (SCC). This clinical dilemma requires a deeper investigation into their differences. Herein a transcriptomic atlas of SCC, HPVA, and NHPVA-ADC using single-cell RNA (scRNA) and T-cell receptor sequencing (TCR-seq) is presented. Regarding structural cells, the malignancy origin of epithelial cells, angiogenic tip cells and two subtypes of fibroblasts is revealed. The promalignant properties of the structural cells using organoids are further confirmed. Regarding immune cells, myeloid cells with multiple functions other than antigen presentation and exhausted T lymphocytes contribute to immunosuppression. From the perspective of HPV infection, not only is HPV-dependent and independent cervical cancer oncogenesis proposed but also three immune reaction patterns mediated by T cells (coordinated/inactive/imbalanced) are identified. Strikingly, diagnostic biomarkers to distinguish ADC from SCC are discovered and prognostic biomarkers with marker genes for malignant epithelial cells, tip cells, and SPP1/C1QC macrophages are generated. Importantly, the efficacy of anti-CD96 and anti-TIGIT, not inferior to anti-PD1, in animal experiments is confirmed and targeted therapies specifically for HPV-positive SCC, HPVA and NHPVA-ADC, providing essential clues for further clinical trials, are proposed.

Loss-of-function mutations of SOX17 lead to YAP/TEAD activation-dependent malignant transformation in endometrial cancer

Aberrant hyperactivation of the Hippo pathway effector YAP/TEAD complex causes tissue overgrowth and tumorigenesis in various cancers, including endometrial cancer (EC). The transcription factor SOX17 (SRY [sex-determining region Y]-box 17) is frequently mutated in EC; however, SOX17 mutations are rare in other cancer types. The molecular mechanisms underlying SOX17 mutation-induced EC tumorigenesis remain poorly understood. Here, we demonstrate that SOX17 serves as a tumor suppressor to restrict the proliferation, migration, invasion, and anchorage-independent growth of EC cells, partly by suppressing the transcriptional outputs of the Hippo-YAP/TEAD pathway. SOX17 binds to TEAD transcription factors through its HMG domain and attenuates the DNA-binding ability of TEAD. SOX17 loss by inactivating mutations leads to the malignant transformation of EC cells, which can be reversed by small-molecule inhibitors of YAP/TEAD or cabozantinib, an FDA-approved drug targeting the YAP/TEAD transcriptional target AXL. Our findings reveal novel molecular mechanisms underlying Hippo-YAP/TEAD pathway-driven EC tumorigenesis, and suggest potential therapeutic strategies targeting the Hippo-YAP/TEAD pathway in SOX17-mutated EC.

CHRNB2 represses pancreatic cancer migration and invasion via inhibiting β-catenin pathway

Background

Pancreatic cancer is one of the most lethal disease with highly fatal and aggressive properties. Lymph node ratio (LNR), the ratio of the number of metastatic lymph nodes to the total number of examined lymph nodes, is an important index to assess lymphatic metastasis and predict prognosis, but the molecular mechanism underlying high LNR was unclear.

Methods

Gene expression and clinical information data of pancreatic cancer were obtained from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). Patients in TCGA were averagely divided into low and high LNR groups. Then, Weighted Gene Co-expression Network Analysis (WGCNA) was utilized to build co-expression network to explore LNR-related modules and hub genes. GO and KEGG analysis was performed to find key pathways related to lymph node metastasis. Next, GSE101448 and the overall survival data in TCGA was employed to further select significant genes from hub genes. Considering the key role of CHRNB2 in LNR and survival, gene set enrichment analysis (GSEA) was applied to find pathways related to CHRNB2 expression in pancreatic cancer. The contribution of CHRNB2 to migrative and invasive ability of pancreatic cancer cells was confirmed by Transwell assays. We finally explored the role of CHRNB2 in EMT and β-catenin pathway via Western Blot.

Results

High LNR was significantly related to high T stages and poor prognosis. In WGCNA, 14 hub genes (COL5A1, FN1, THBS2, etc.) were positively related to high LNR, 104 hub genes (FFAR1, SCG5, TMEM63C, etc.) were negatively related to high LNR. After taking the intersection with GSE101448, 13 genes (CDK5R2, SYT7, CACNA2D2, etc.) which might prevent lymph node metastasis were further selected. Among them, CHRNB2 showed the strongest relationship with long survival. Moreover, CHRNB2 also negatively related to the T stages and LNR. Next, knockdown of CHRNB2 expression could acetylcholine (ACh)-independently increase the migration and invasion of pancreatic cancer cells, while CHRNB2 overexpression ACh-independently decrease the migration and invasion of pancreatic cancer cells. For exploring the underlying mechanism, CHRNB2 downregulated β-catenin pathway might through controlling its upstream regulators such as SOX6, SRY, SOX17, and TCF7L2.

Conclusions

CHRNB2 negatively relates to lymph node metastasis in pancreatic cancer patients. CHRNB2 could inhibit β-catenin pathway, EMT, migration and invasion of pancreatic cancer cells via ACh-independent mechanism.

The Biomarker Like the Correlation between Vasculogenic Mimicry, Vascular Endothelial Cadherin, Sex-DeterminingRegion on Y-Box Transcription Factor 17, and Cyclin D1 in Oesophageal Squamous Cell Carcinoma

Background

This study aimed to explore the relationships between the sex-determining region on Y (SRY) box transcription factor 17 (SOX17), Cyclin D1, vascular endothelial cadherin (VE-cadherin), and vasculogenic mimicry (VM) in the occurrence and development of esophageal squamous cell carcinoma (ESCC).

Methods

The expressions of SOX17, Cyclin D1, and VE-cadherin, as well as VM, in tissues, were determined using immunohistochemistry. SOX17, Cyclin D1, and VE-cadherin mRNA in ESCC and their corresponding adjacent normal tissues were quantified using quantitative reverse transcription polymerase chain reaction analysis. Cell invasion, migration, and proliferation were determined after the silencing of VE-cadherin. SOX17, Cyclin D1, and VE-cadherin protein were quantified using Western blotting.

Results

The expression levels of SOX17, Cyclin D1, and VE-cadherin significantly correlated with the clinical characteristics of ESCC. After the VE-cadherin silencing, cell invasion, migration, and proliferation decreased, along with the Cyclin D1 levels, while the SOX17 levels increased.

Conclusion

SOX17, Cyclin D1, and VE-cadherin are involved in the development of ESCC.

HNF4A Regulates the Proliferation and Tumor Formation of Cervical Cancer Cells through the Wnt/β-Catenin Pathway

Hepatocyte nuclear factor 4 alpha (HNF4A) is a transcriptional factor which plays an important role in the development of the liver, kidney, and intestines. Nevertheless, its role in cervical cancer and the underlying mechanism remain unknown. In this study, both immunohistochemistry and western blotting revealed that the expression of HNF4A was downregulated in cervical cancer. Xenograft assays suggested that HN4A could inhibit tumorigenic potential of cervical cancer in vivo. Functional studies illustrated that HNF4A also inhibited the proliferation and viability of cervical cancer cells in vitro. In addition, FACS analysis implied that HNF4A could induce cell cycle arrest from the G0/G1 phase to S phase. Further studies suggested that HNF4A downregulated the activity of the Wnt/β-catenin pathway. Altogether, our data demonstrated that HNF4A inhibited tumor formation and proliferation of cervical cancer cells through suppressing the activity of the Wnt/β-catenin pathway.

The CpG island methylator phenotype increases the risk of high-grade squamous intraepithelial lesions and cervical cancer

Background

High-risk human papillomavirus (HR-HPV) infection is the main cause of cervical cancer, but additional alterations are necessary for its development. Abnormal DNA methylation has an important role in the origin and dissemination of cervical cancer and other human tumors. In this work, we analyzed the methylation of eight genes (AJAP1, CDH1, CDH13, MAGI2, MGMT, MYOD1, RASSF1A and SOX17) that participate in several biological processes for the maintenance of cell normality. We analyzed DNA methylation by methylation-specific PCR (MSP) and HPV infection using the INNO‑LiPA genotyping kit in 59 samples diagnostic of normal cervical tissue (non-SIL), 107 low-grade squamous intraepithelial lesions (LSILs), 29 high-grade squamous intraepithelial lesions (HSILs) and 51 cervical cancers (CCs).

Results

We found that all samples of LSIL, HSIL, and CC were HPV-positive, and the genotypes with higher frequencies were 16, 18, 51 and 56. In general, the genes analyzed displayed a significant tendency toward an increase in methylation levels according to increasing cervical lesion severity, except for the CDH13 gene. High CpG island methylator phenotype (CIMP) was associated with a 50.6-fold (95% CI 4.72–2267.3)-increased risk of HSIL and a 122-fold risk of CC (95% CI 10.04–5349.7).

Conclusions

We found that CIMP high was significantly associated with HSIL and CC risk. These results could indicate that CIMP together with HR-HPV infection and other factors participates in the development of HSIL and CC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13148-021-01224-0.

Cervical cancer progression is regulated by SOX transcription factors: Revealing signaling networks and therapeutic strategies

Cervical cancer is the fourth common gynecologic cancer and is considered as second leading cause of death among women. Various strategies are applied in treatment of cervical cancer including radiotherapy, chemotherapy and surgery. However, cervical cancer cells demonstrate aggressive behavior in advanced phases, requiring novel strategies in their elimination. On the other hand, SOX proteins are transcription factors capable of regulating different molecular pathways and their expression varies during embryogenesis, disease development and carcinogenesis. In the present review, our aim is to reveal role of SOX transcription factors in cervical cancer. SOX transcription factors play like a double-edged sword in cancer. For instance, SOX9 possesses both tumor-suppressor and tumor-promoting role in cervical cancer. Therefore, exact role of each SOX members in cervical cancer has been discussed to direct further experiments for revealing other functions. SOX proteins can regulate proliferation and metastasis of cervical cancer cells. Furthermore, response of cervical cancer cells to chemotherapy and radiotherapy is tightly regulated by SOX transcription factors. Different downstream targets of SOX proteins such as Wnt signaling, EMT and Hedgehog have been identified. Besides, upstream mediators such as microRNAs, lncRNAs and circRNAs can regulate SOX expression in cervical cancer. In addition to pre-clinical studies, role of SOX transcription factors as prognostic and diagnostic tools in cervical cancer has been shown.

Pan-cancer analysis combined with experiments predicts CTHRC1 as a therapeutic target for human cancers

BACKGROUND

The function of collagen triple helix repeat containing 1 (CTHRC1) as an oncogene has been reported in a growing number of publications. Bioinformatics methods represent a beneficial approach to examine the mechanism and function of the CTHRC1 gene in the disease process of cancers from a pan-cancer perspective.

METHODS

In this study, using the online databases UCSC, NCBI, HPA, TIMER2, Oncomine, GEPIA, UALCAN, cBioPortal, COSMIC, MEXPRESS, STRING, CCLE, LinkedOmics, GTEx, TCGA, CGGA, and SangerBox, we focused on the relationship between CTHRC1 and tumorigenesis, progression, methylation, immunity, and prognosis. qPCR was used to detect CTHRC1 expression in glioma tissues and cell lines.

RESULTS

The pan-cancer analysis showed that CTHRC1 was overexpressed in most tumors, and a significant correlation was observed between CTHRC1 expression and the prognosis of patients with cancer. CTHRC1 genetic alterations occur in diverse tumors and are associated with tumor progression. Levels of CTHRC1 promoter methylation were decreased in most cancer tissues compared with normal tissues. In addition, CTHRC1 coordinated the activity of ICP genes through diverse signal transduction pathways, was also associated with immune cell infiltration and the tumor microenvironment, and potentially represented a promising immunotherapy target. We identified CTHRC1-related genes across cancers using the GEPIA2 tool. The single-gene GO analysis of CTHRC1 across cancers showed that it was involved in some signaling pathways and biological processes, such as the Wnt signaling pathway, cell migration, and positive regulation of protein binding. The expression and function of CTHRC1 were also further verified in glioma tissues and cell lines.

CONCLUSIONS

CTHRC1 is overexpressed in various cancer types and functions as an important oncogene that may promote tumorigenesis and development through different mechanisms. CTHRC1 may represent an important therapeutic target for human cancers.

QKI-Regulated Alternative Splicing Events in Cervical Cancer: Pivotal Mechanism and Potential Therapeutic Strategy

QKI is a vital regulator in RNA splicing and maturation, but its role in cervical cancer (CC) is little known. In this study, we found that QKI is decreased in human CC, and overexpression of QKI inhibits HeLa cell proliferation and promotes the apoptosis of cancer cells. We identified hundreds of endogenous QKI-regulated alternative splicing events (ASEs) and differentially expressed genes (DEGs) in QKI-overexpressed HeLa cells by RNA-seq and selectively validated their expression by quantitative reverse-transcription polymerase chain reaction. The gene ontology and Kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis showed that QKI-regulated ASEs and DEGs were closely related to cancer, apoptosis, and transcriptional regulatory functions. In short, QKI may affect the occurrence and development of CC by regulating gene expression through AS.

The Role of the Wnt Pathway in VEGF/Anti-VEGF-Dependent Control of the Endothelial Cell Barrier

Purpose

Investigate the contribution of the Wnt pathway to vascular endothelial growth factor (VEGF)/anti-VEGF-mediated control of endothelial cell permeability.

Methods

High glucose-treated primary human retinal endothelial cells (HRECs) were exposed to either VEGF, or VEGF and then anti-VEGF. Changes in gene expression were assayed by RNAseq and qRT-PCR. Permeability was monitored by electrical cell-substrate impedance sensing (ECIS). Approaches to activate the Wnt pathway included treatment with LiCl and overexpression of constitutively activated β-catenin. β-catenin-dependent transcriptional activity was monitored in HRECs stably expressing a TCF/LEF-driven reporter.

Results

VEGF/anti-VEGF altered expression of genes encoding many members of the Wnt pathway. A subset of these genes was regulated in a way that is likely to contribute to control of the endothelial cell barrier. Namely, the VEGF-induced alteration of expression of such genes was reversed by anti-VEGF, and such adjustments occurred at times corresponding to changes in barrier function. While pharmacological and molecular approaches to activate the Wnt pathway had no effect on basal permeability, they suppressed VEGF-induced relaxation. Furthermore, anti-VEGF-mediated restoration of barrier function was unaffected by activation of the Wnt pathway.

Conclusions

VEGF/anti-VEGF engages multiple members of the Wnt pathway, and activating this pathway enforces the endothelial barrier by attenuating VEGF-induced relaxation. These data suggest that FDA-approved agents such as LiCl may be an adjuvant to anti-VEGF therapy for patients afflicted with blinding conditions including diabetic retinopathy.

Prognostic and clinicopathological significance of TMEFF2, SMOC-2, and SOX17 expression in endometrial carcinoma

Background there is a need for novel biomarkers and targeting therapies for predicting Endometrial carcinoma (EC) progression and recurrence. TMEFF2 is a gene that was found to play a role in EMT. SMOC-2 is expressed in embryogenesis and it was identified as a recent stem cell-related gene that has a role in cancer progression. SRY-box 17 (SOX17) is a member of the SRY-related HMG-box (SOX) family of transcription factors. Dysregulation or downregulation of SOX17 expression was found in many cancer tissues.

AIM

In the present study, we aimed to assess the tissue protein expressions of TMEFF2, SMOC-2, and SOX17 in EC using immunohistochemistry to evaluate their clinicopathological values and prognostic roles in EC patients.

PATIENTS AND METHODS

This is prospective cohort study included 120 patients with EC. Sections from 120 paraffin blocks were retrieved and stained with TMEFF2, SMOC-2, and SOX17 using immunohistochemistry, the expression of markers in all tissue samples was assessed, analyzed and correlation of pathological parameters with the levels of expression was done. All patients were followed up till death or till the last known alive data for about 50 months (range from 25 to 60).

RESULTS

TMEFF2, SMOC-2 expression was correlated with the presence of lymph node metastases (p = 0.023), distant metastasis (p = 0.039) recurrence of the tumor after successful therapy, overall survival, and disease-free survival (p < 0.001). SOX17 positive expression was positively correlated with low grade (p = 0.019), absence of lymph node metastasis (p = 0.001), absence of distant metastasis (p = 0.013), low stage (p = 0.03), and its negative expression was positively correlated with recurrence of the tumor after successful therapy, overall survival and disease-free survival (p = 0.001). In conclusion, we demonstrated that both TMEFF2 and SMOC-2 were highly expressed in EC and were associated with a shortened survival rate, dismal outcome, and poor prognosis in EC patients. While SOX17 expression was related to a favorable outcome and its down-regulation was associated with dismal EC patient's survival.

SOX17 inhibits proliferation and invasion of neuroblastoma through CXCL12/CXCR4 signaling axis

SOX17 has been shown to be involved in the transcriptional regulation of CXCR4, and CXCL12 functions by binding to its receptor CXCR4. Here, we explored the expression of SOX17 in neuroblastoma (NB), its mutual regulation with CXCL12, and its effects on cancer cell proliferation, migration and invasion. Five human NB cell lines and 15 pairs of NB and adjacent tissue specimens were used, to conduct RT-qPCR, immunohistochemistry, western blot, ELISA, CCK-8, colony formation, Edu, transwell, chromatin immunoprecipitation (ChIP), and dual-luciferase assays, to study the role of SOX17 in NB. SOX17 levels were reduced in both NB tissues and cell lines. SOX17 inhibited NB tumor growth, migration and invasion in vivo and suppressed NB cell proliferation, migration, and invasion in vitro. SOX17 knockdown or overexpression revealed a negative correlation between SOX17 and CXCL12/CXCR4 pathway activation. ChIP and dual-luciferase assays in NB cells demonstrated that SOX17 significantly inhibited CXCL12 gene and protein levels by binding to CXCL12 promoter regions. In vivo and in vitro experiments using the CXCR4 antagonist, AMD3100, demonstrated that cell proliferation, migration and invasion were significantly abrogated by AMD3100 in NB cells with SOX17 knocked down. Further, AMD3100 impaired growth of NB tumors with SOX17 knocked down in mice. Importantly, SOX17 bound to the CXCL12 promoter, which then activated downstream targets to regulate cell viability, proliferation, and migration. In conclusion, our data demonstrate that SOX17 expression is repressed in NB tissues and cells, and that SOX17 suppresses NB tumor formation and proliferation through inhibition of CXCL12/CXCR4 signaling.

N-methyladenosine reader YTHDF2-mediated long noncoding RNA FENDRR degradation promotes cell proliferation in endometrioid endometrial carcinoma

Dysregulation of long noncoding RNA (LncRNA) FENDDR has been shown to be closely related to the progression of several cancers. However, its role and upstream regulatory mechanism in endometrioid endometrial carcinoma (EEC) remains unclear. This study was conducted using the cancerous tissues of EEC patients (n = 60), EEC cell lines, and a xenograft mouse model. The expression level of LncRNA FENDRR was decreased and the N-methyladenosine (m6A) methylation levels of LncRNA FENDRR was elevated in cancerous tissues of EEC patients. In vitro experiments demonstrated that YTH domain-containing 2 (YTHDF2), an m6A reader, recognized the abundance of m6A-modified LncRNA FENDRR in EEC cells and promoted its degradation. LncRNA FENDRR overexpression suppressed cell proliferation and facilitated cell apoptosis in the EEC cell line HEC-1B by reducing the protein level of SRY-related HMG box transcription factor 4 (SOX4). Interference of LncRNA FENDRR reversed the inhibitory effect of sh-YTHDF2 on cell proliferation and the promoting effect of sh-YTHDF2 on cell apoptosis in HEC-1B cells by silencing FENDRR. Finally, in vivo experiments confirmed that overexpression of LncRNA FENDRR retarded the growth of EEC cells. In conclusion, YTHDF2-mediated LncRNA FENDRR degradation promotes cell proliferation by elevating SOX4 expression in EEC.

DNA methylation association with stage progression of head and neck squamous cell carcinoma

Head and Neck Squamous Cell Carcinoma (HNSCC) is the sixth most common cancer worldwide, which accounts for approximately 6% of all cases and is responsible for an estimated 2% of all cancer deaths. Despite progress in the treatment of squamous cell carcinomas, survival rates remain low. It is a fact that epigenetic modifications have numerous associations with biological processes and complex diseases such as cancer. Hence, a more systematic approach is needed to provide potential screening targets and have an effective therapy method. This study developed a workflow to analyze HM450 methylation arrays with mRNA expression profiles that identified novel signatures of epigenetic regulators for tumor progression. We identified differentially expressed genes and differentially methylated regions and the correlation between associated genes to identify epigenetic modifications underlying regulation roles. We have taken the differentiation direction of expressions into account during the integration of gene expression and DNA methylation modification to detect epigenetic regulators of core genes of tumor-stage progression. Enrichment analysis of selected key genes provides better insight into their functionality. Thus, we have investigated gene copy number alteration and mutations to filter differentially expressed genes, including some members of the fibroblast growth factor family and cyclin-dependent kinase inhibitor family with other potential known regulators. Our analysis has revealed the list of 61 commercial methylation probes positively correlated with 31 differentially expressed genes, which can be associated with HNSC metastasis stages. Most of these genes have already reported potential epigenetic regulators, and their role in cancer progression was studied. We suggest these selected probes of DNA methylation as potential targets of the epigenetic regulators in revealed genes that have displayed significant genetic and epigenetic modification behavior during cancer stage progression and tumor metastasis.

Discovery of Candidate DNA Methylation Cancer Driver Genes

Epigenetic alterations, such as promoter hypermethylation, may drive cancer through tumor suppressor gene inactivation. However, we have limited ability to differentiate driver DNA methylation (DNAme) changes from passenger events. We developed DNAme driver inference-MethSig-accounting for the varying stochastic hypermethylation rate across the genome and between samples. We applied MethSig to bisulfite sequencing data of chronic lymphocytic leukemia (CLL), multiple myeloma, ductal carcinoma in situ, glioblastoma, and to methylation array data across 18 tumor types in TCGA. MethSig resulted in well-calibrated quantile-quantile plots and reproducible inference of likely DNAme drivers with increased sensitivity/specificity compared with benchmarked methods. CRISPR/Cas9 knockout of selected candidate CLL DNAme drivers provided a fitness advantage with and without therapeutic intervention. Notably, DNAme driver risk score was closely associated with adverse outcome in independent CLL cohorts. Collectively, MethSig represents a novel inference framework for DNAme driver discovery to chart the role of aberrant DNAme in cancer. SIGNIFICANCE: MethSig provides a novel statistical framework for the analysis of DNA methylation changes in cancer, to specifically identify candidate DNA methylation driver genes of cancer progression and relapse, empowering the discovery of epigenetic mechanisms that enhance cancer cell fitness.This article is highlighted in the In This Issue feature, p. 2113.

Targeting a positive regulatory loop in the tumor-macrophage interaction impairs the progression of clear cell renal cell carcinoma

Although the interaction between tumors and tumor-associated macrophages (TAMs) has been reported to facilitate the targeted drug resistance and progression of clear cell renal cell carcinoma (ccRCC), the related mechanisms remain unknown. Here, we report that SOX17 serves as a novel tumor suppressor in ccRCC and a positive regulatory loop, SOX17low/YAP/TEAD1/CCL5/CCR5/STAT3, facilitates the ccRCC-TAM interaction. SOX17 expression was commonly downregulated and negatively correlated with TAM infiltration in ccRCC specimens, and the integration of SOX17 and TAMs with the existing clinical indicators TNM stage or SSIGN score achieved better accuracy for predicting the prognosis of ccRCC patients. Mechanistically, SOX17 knockdown activated YAP signaling by promoting the transcription and nuclear distribution of YAP, which recruited TEAD1 to trigger CCL5 transcription. Then, CCL5 educated macrophages toward TAMs, which reciprocally enhanced ccRCC progression through CCL5/CCR5 and activated STAT3/SOX17low/YAP. However, SOX17 overexpression in ccRCC achieved the opposite effect. Thus, a positive regulatory loop, SOX17low/YAP/TEAD1/CCL5/CCR5/STAT3, was identified in the ccRCC-TAM interaction. Furthermore, targeting tumor-TAM interactions by blocking this positive regulatory network impaired the metastasis and targeted drug resistance of ccRCC in in vivo mouse models of lung metastasis and orthotopic ccRCC. These findings provide a new mechanism underlying the tumor-TAM interplay in ccRCC progression and present a potential target for inhibiting targeted drug resistance and metastasis in advanced ccRCC.

MicroRNA-194: a novel regulator of glucagon-like peptide-1 synthesis in intestinal L cells

In the status of obesity, the glucagon-like peptide-1 (GLP-1) level usually declines and results in metabolic syndrome. This study aimed to investigate the intracellular mechanism of GLP-1 synthesis in L cells from the perspective of microRNA (miRNA). In the present study, we found that GLP-1 level was down-regulated in the plasma and ileum tissues of obese mice, while the ileac miR-194 expression was up-regulated. In vitro experiments indicated that miR-194 overexpression down-regulated GLP-1 level, mRNA levels of proglucagon gene (gcg) and prohormone convertase 1/3 gene (pcsk1), and the nuclear protein level of beta-catenin (β-catenin). Further investigation confirmed that β-catenin could promote gcg transcription through binding to transcription factor 7-like 2 (TCF7L2). miR-194 suppressed gcg mRNA level via negatively regulating TCF7L2 expression. What’s more, forkhead box a1 (Foxa1) could bind to the promoter of pcsk1 and enhanced its transcription. miR-194 suppressed pcsk1 transcription through targeting Foxa1. Besides, the interference of miR-194 reduced palmitate (PA)-induced cell apoptosis and the anti-apoptosis effect of miR-194 inhibitor was abolished by TCF7L2 knockdown. Finally, in HFD-induced obese mice, the silence of miR-194 significantly elevated GLP-1 level and improved the metabolic symptoms caused by GLP-1 deficiency. To sum up, our study found that miR-194 suppressed GLP-1 synthesis in L cells via inhibiting TCF7L2-mediated gcg transcription and Foxa1-mediated pcsk1 transcription. Meanwhile, miR-194 took part in the PA-induced apoptosis of L cells.

HOXB4 inhibits the proliferation and tumorigenesis of cervical cancer cells by downregulating the activity of Wnt/β-catenin signaling pathway

Homeobox B4 (HOXB4), which belongs to the homeobox (HOX) family, possesses transcription factor activity and has a crucial role in stem cell self-renewal and tumorigenesis. However, its biological function and exact mechanism in cervical cancer remain unknown. Here, we found that HOXB4 was markedly downregulated in cervical cancer. We demonstrated that HOXB4 obviously suppressed cervical cancer cell proliferation and tumorigenic potential in nude mice. Additionally, HOXB4-induced cell cycle arrest at the transition from the G0/G1 phase to the S phase. Conversely, loss of HOXB4 promoted cervical cancer cell growth both in vitro and in vivo. Bioinformatics analyses and mechanistic studies revealed that HOXB4 inhibited the activity of the Wnt/β-catenin signaling pathway by direct transcriptional repression of β-catenin. Furthermore, β-catenin re-expression rescued HOXB4-induced cervical cancer cell defects. Taken together, these findings suggested that HOXB4 directly transcriptional repressed β-catenin and subsequently inactivated the Wnt/β-catenin signaling pathway, leading to significant inhibition of cervical cancer cell growth and tumor formation.

LGR6 activates the Wnt/β-catenin signaling pathway and forms a β-catenin/TCF7L2/LGR6 feedback loop in LGR6high cervical cancer stem cells

The leucine-rich repeat-containing G-protein-coupled receptor 6 (LGR6) is considered to be a stem cell marker in many normal tissues and promotes tissue development, regeneration, and repair. LGR6 is also related to the initiation and progression of some malignant tumors. However, the role of LGR6 in cervical cancer has not been reported. Here, immunohistochemistry and western blotting showed that LGR6 was significantly upregulated in cervical cancer, compared with the normal cervix. By analyzing The Cancer Genome Atlas database, LGR6 was found to be correlated with a poor prognosis of cervical cancer. Then, a small population of LGR6^high cells isolated by using the fluorescence-activated cell sorting exhibited enhanced properties of cancer stem cells including self-renewal, differentiation, and tumorigenicity. Moreover, RNA sequencing revealed that LGR6 was correlated with the Wnt signaling pathway and TOP/FOP, reverse transcription-PCR, and western blotting further proved that LGR6 could activate the Wnt/β-catenin signaling pathway. Interestingly, LGR6 upregulated the expression of TCF7L2 by activating the Wnt/β-catenin pathway. Then, TCF7L2 combining with β-catenin in the nucleus enhanced LGR6 transcription by binding the promoter of LGR6, which further activated the Wnt signaling to form a positive feedback loop. Thus, our study demonstrated that LGR6 activated a novel β-catenin/TCF7L2/LGR6-positive feedback loop in LGR6^high cervical cancer stem cells (CSCs), which provided a new therapeutic strategy for targeting cervical CSCs to improve the prognosis of cervical cancer patients.

PRDM4 inhibits cell proliferation and tumorigenesis by inactivating the PI3K/AKT signaling pathway through targeting of PTEN in cervical carcinoma

PR domain zinc finger protein 4 (PRDM4) is a transcription factor that plays key roles in stem cell self-renewal and tumorigenesis. However, its biological role and exact mechanism in cervical cancer remain unknown. Here, both immunohistochemistry (IHC) and Western blot assays demonstrated that the expression of PRDM4 in cervical cancer tissues was much lower than that in the normal cervix. A xenograft assay showed that PRDM4 overexpression in the cervical cancer cell lines SiHa and HeLa dramatically inhibited cell proliferation and tumorigenic potential in vivo. Conversely, the silencing of PRDM4 promoted cervical cancer cell proliferation and tumorigenic potential. Mechanistically, PRDM4 induced cell cycle arrest at the transition from G0/G1 phase to S phase by upregulating p27 and p21 expression and downregulating Cyclin D1 and CDK4 expression. Furthermore, the PI3K/AKT signaling pathway was inactivated in PRDM4-overexpressing cells, which decreased the levels of p-AKT and upregulated the expression of PTEN, an inhibitor of the PI3K/AKT signaling pathway, at both the transcriptional and translational levels. Dual-luciferase reporter assays and qChIP assays confirmed that PRDM4 transactivated the expression of PTEN by binding to two specific regions in the PTEN promoter. Furthermore, PTEN silencing or a PTEN inhibitor rescued the cell defects induced by PRDM4 overexpression. Therefore, our data suggest that PRDM4 inhibits cell proliferation and tumorigenesis by downregulating the activity of the PI3K/AKT signaling pathway by directly transactivating PTEN expression in cervical cancer.

Sry-related High Mobility Group Box 17 Functions as a Tumor Suppressor by Antagonizing the Wingless-related Integration Site Pathway

A transcription factor Sry-related high mobility group box (Sox) 17 is involved in developmental processes including spermatogenesis, cardiovascular system, endoderm formation, and so on. In this article, we firstly review the studies on the relation between the Sox17 expression and tumor malignancy. Although Sox17 positively promotes various tissue development, most of the cancers associated with Sox17 show decreased expression levels of Sox17, and an inverse correlation between Sox17 expression and malignancy is revealed. We briefly discuss the mechanism of such Sox17 down-regulation by focusing on DNA methylation of CpG sites located in the Sox17 gene promoter. Next, we overview the function of Sox17 in the fetal hematopoiesis, particularly in the dorsal aorta in midgestation mouse embryos. The Sox17 expression in hematopoietic stem cell (HSC)-containing intra-aortic hematopoietic cell cluster (IAHCs) is important for the cluster formation with the hematopoietic ability. The sustained expression of Sox17 in adult bone marrow HSCs and the cells in IAHCs of the dorsal aorta indicate abnormalities that are low lymphocyte chimerism and the aberrant proliferation of common myeloid progenitors in transplantation experiments. We then summarize the perspectives of Sox17 research in cancer control.

miR-937-5p targets SOX17 to modulate breast cancer cell cycle and cell proliferation through the Wnt signaling pathway

Breast cancer is one of the most frequent cancers in women and the globally leading cause of cancer-related deaths. Bioinformatics and experimental analyses found that miR-937-5p may play a proto-oncogenic role in breast cancer; however, the specific effects and the molecular mechanism need further investigation. GSEA-KEGG and GSEA-GO suggested that miR-937-5p might be related to cell cycle and DNA replication. The experimental data indicated that miR-937-5p inhibition significantly repressed the proliferation of breast carcinoma cells and elicited S-phase cell cycle arrest. Meanwhile, the protein levels of proliferating marker ki-67 and cell cycle regulators Cyclin A2, Cyclin B1, CDK1, and Cyclin D1 were also decreased by miR-937-5p inhibition. miR-937-5p could directly bind to and negatively regulate SOX17. SOX17 overexpression also significantly repressed the proliferation of breast carcinoma cells and elicited S-phase cell cycle arrest and decreased ki-67, β-catenin, c-Myc, Cyclin A2, Cyclin B1, Cyclin D1, and CDK1 protein contents. More importantly, the effects of miR-937-5p were reversed by SOX17.

β-Catenin: oncogenic role and therapeutic target in cervical cancer

Cervical cancer is a common and fatal malignancy of the female reproductive system. Human papillomavirus (HPV) is the primary causal agent for cervical cancer, but HPV infection alone is insufficient to cause the disease. Actually, most HPV infections are sub-clinical and cleared spontaneously by the host immune system; very few persist and eventually develop into cervical cancer. Therefore, other host or environmental alterations could also contribute to the malignant phenotype. One of the candidate co-factors is the β-catenin protein, a pivotal component of the Wnt/β-catenin signaling pathway. β-Catenin mainly implicates two major cellular activities: cell–cell adhesion and signal transduction. Recent studies have indicated that an imbalance in the structural and signaling properties of β-catenin leads to various cancers, such as cervical cancer. In this review, we will systematically summarize the role of β-catenin in cervical cancer and provide new insights into therapeutic strategies.

Wnt Signaling in Gynecologic Malignancies

Gynecologic malignancies, including ovarian cancer, endometrial cancer, and cervical cancer, affect hundreds of thousands of women worldwide every year. Wnt signaling, specifically Wnt/β-catenin signaling, has been found to play an essential role in many oncogenic processes in gynecologic malignancies, including tumorigenesis, metastasis, recurrence, and chemotherapy resistance. As such, the Wnt/β-catenin signaling pathway has the potential to be a target for effective treatment, improving patient outcomes. In this review, we discuss the evidence supporting the importance of the Wnt signaling pathways in the development, progression, and treatment of gynecologic malignancies.

HOXA5 inhibits the proliferation and neoplasia of cervical cancer cells via downregulating the activity of the Wnt/β-catenin pathway and transactivating TP53

HOXA5 is considered a regulator involved in embryonic development and cellular differentiation and a tumor suppressor. Nevertheless, its biological role in cervical carcinoma is still unclear. In the present study, immunohistochemistry showed that HOXA5 expression gradually decreased as the degree of cervical lesions deepened. Ectopic expression of HOXA5 restrained cell proliferation, decreased cell viability, and inhibited tumor formation in vitro and in vivo. Furthermore, the expression of HOXA5 could arrest cell cycle from G0/G1 to S phase. RNA-seq revealed that p21 and cyclinD1 were involved in this process. Moreover, the gene set enrichment analysis and the TOP/FOP reporter assay both suggested that HOXA5 could restrain the activity of the Wnt/β-catenin pathway. Further study using dual-luciferase reporter assay and quantitative chromatin immunoprecipitation assay demonstrated that HOXA5 could directly bind to the TAAT motif within the promoter of TP53 by its HD domain and transactivate TP53, which can upregulate p21. Altogether, our data suggest that HOXA5 inhibits the proliferation and neoplasia via repression activity of the Wnt/β-catenin pathway and transactivating TP53 in cervical cancer.

SOX17 expression and its down-regulation by promoter methylation in cervical adenocarcinoma in situ and adenocarcinoma

AIMS

SOX17 expression has not been studied in glandular lesions of the uterine cervix like adenocarcinoma in situ (AIS) and invasive adenocarcinomas (AdC), whereas SOX17 promoter CpG island methylation has been reported. Therefore, the aim of this study was to relate the topographical distribution of SOX17 expression and SOX17 methylation status to each other, and to SOX2 expression, human papillomavirus (HPV) type, and physical status of the virus.

METHODS AND RESULTS

Immunohistochemistry was used in 45 cases to assess expression of SOX17 and SOX2. SOX17 promoter methylation was determined in 25 cases by means of bisulphite conversion and methylation-specific polymerase chain reaction. SOX17 and SOX2 showed a mutually exclusive expression pattern in normal epithelium, with a sharp delineation in the squamocolumnar junction. SOX17 was found in endocervical columnar and reserve cells, whereas SOX2 was exclusively found in squamous epithelium. In both glandular lesions and cases with coexisting glandular and squamous intraepithelial components, a complex combination of SOX17 and SOX2 expression patterns was seen and mutually exclusive expression was lost. Frequently, gain of expression of SOX2 was found and expression of SOX17 was lost. Methylation of the CpG island in the SOX17 promoter was shown to be strongly associated with loss of expression of SOX17 (P = 0.0016).

CONCLUSIONS

In this study, we show for the first time a direct correlation between the topographical distribution of SOX17 expression and the methylation status of its gene promoter. This explains the heterogeneity of SOX17 expression in the glandular lesions of the cervix. No correlation was found between HPV type and physical status of the virus on the one hand and methylation status on the other.

Diverse pathogenetic roles of SOX genes in acute myeloid leukaemia and their therapeutic implications

Acute myeloid leukaemia (AML) is a heterogeneous group of diseases with diverse pathogenetic pathways. When treated uniformly with conventional chemotherapy and allogeneic haematopoietic stem cell transplantation (HSCT), it showed variable clinical outcome and prognosis. Members of the SOX [Sry-related high-mobility group (HMG) box] gene family are involved in diverse embryonic and oncogenic processes. The roles of SOX genes in AML are not entirely clear but emerging evidence, including that arising from studies in solid-cancers, showed that SOX genes can function as tumour suppressors or oncogenes and may be involved in key pathogenetic pathways in AML involving C/EBPα mutations, activation of β-catenin/Wnt and Hedgehog pathways and aberrant TP53 signals. Recent data based on genomics and proteomics have identified key interactions between SOX genes and partnering proteins of pathogenetic significance. The observations illustrated the principles and feasibilities of developing lead molecules of potential therapeutic values. Studying the diverse pathogenetic roles of SOX genes in AML may shed lights to the heterogeneity of AML and generate information that can be translated into novel therapeutic strategies.

CCL14 serves as a novel prognostic factor and tumor suppressor of HCC by modulating cell cycle and promoting apoptosis

CCL14 is a member of CC chemokines and its role in hepatocellular carcinoma (HCC) is still unknown. In this study, CCL14 expression were analyzed by tissue microarray (TMA) including 171 paired tumor and peritumor tissues of patients from Zhongshan Hospital of Fudan University. We found for the first time that CCL14 was downregulated in HCC tumor tissues compared with peritumor tissues (P = 0.01). Meanwhile, CCL14 low expression in HCC tumor tissues is associated with a poor prognosis (P = 0.035). CCL14 also displayed its predictive value in high differentiation (P = 0.026), liver cirrhosis (P = 0.003), and no tumor capsule (P = 0.024) subgroups. The underlying mechanisms were further investigated in HCC cell lines by CCL14 overexpression and knock-down in vitro. We found overexpression of CCL14 suppressed proliferation and promoted apoptosis of HCC cells. Finally, the effect was confirmed by animal xenograft tumor models in vivo. The results shown overexpression of CCL14 lead to inhibiting the growth of tumor in nude mice. Interestingly, our data also implied that CCL14 played these effects by inhibiting the activation of Wnt/β-catenin pathway. These findings suggest CCL14 is a novel prognostic factor of HCC and serve as a tumor suppressor.

Cancer-associated missense mutations enhance the pluripotency reprogramming activity of OCT4 and SOX17

The functional consequences of cancer-associated missense mutations are unclear for the majority of proteins. We have previously demonstrated that the activity of SOX and Pit-Oct-Unc (POU) family factors during pluripotency reprogramming can be switched and enhanced with rationally placed point mutations. Here, we interrogated cancer mutation databases and identified recurrently mutated positions at critical structural interfaces of the DNA-binding domains of paralogous SOX and POU family transcription factors. Using the conversion of mouse embryonic fibroblasts to induced pluripotent stem cells as functional readout, we identified several gain-of-function mutations that enhance pluripotency reprogramming by SOX2 and OCT4. Wild-type SOX17 cannot support reprogramming but the recurrent missense mutation SOX17-V118M is capable of inducing pluripotency. Furthermore, SOX17-V118M promotes oncogenic transformation, enhances thermostability and elevates cellular protein levels of SOX17. We conclude that the mutational profile of SOX and POU family factors in cancer can guide the design of high-performance reprogramming factors. Furthermore, we propose cellular reprogramming as a suitable assay to study the functional impact of cancer-associated mutations.

SOX17 Inhibits Tumor Metastasis Via Wnt Signaling In Endometrial Cancer

Background

Endometrial cancer (EC) is the most common gynecological malignancy with high incidence of metastasis, while the mechanism of metastasis in EC is not clear.

Methods

Immunohistochemistry and real-time PCR assays were used to assess expression of SOX17 in paraffin-embedded tissues from EC patients and in EC cells. The migration of EC cells was assessed by wound-healing and Transwell assays as well as in an in vitro study of nude mice. In addition, the expression of specific proteins was analyzed by Western blot.

Results

We observed that SOX17 expression levels were relatively high in stage I EC specimens, and were significantly correlated with the epithelial cadherin (E-cadherin) and β-catenin expression. Additionally, stage II EC patients whose specimens had relatively high SOX17 expression levels had better outcomes. Wound-healing and Transwell assays and in vivo murine experiments revealed that SOX17 inhibited EC cell migration. Meanwhile, SOX17 increased expression of E-cadherin and decreased expression of β-catenin and proteins in the Wnt signaling pathway. Moreover, LiCl (β-catenin activator) enhanced the regulatory effects of SOX17 on the expression of E-cadherin, promigratory cadherin, vimentin, and proteins in the Wnt signaling pathway, while XAV93920 (β-catenin inhibitor) exerted the opposite effect. The SOX17 N-terminus was proved to be necessary for these effects. Mechanistic investigations suggested SOX17 inhibits EC cell migration by inactivating the Wnt/β-catenin–epithelial mesenchymal transition (EMT) axis in EC cells.

Conclusion

We uncovered a common SOX17–β-catenin–EMT mechanism underlying EC cell migration.

FAT1 inhibits the proliferation and metastasis of cervical cancer cells by binding β-catenin

FAT1 is a mutant gene found frequently in human cervical cancer (CC), but its expression and relevance in CC proliferation, invasion, and migration are still unknown. We aimed to explore the role and novel mechanism of FAT1 in CC progression. The expression of FAT1 in CC and adjacent normal tissues was analysed, and we investigated the proliferation, migration, and invasion of HeLa and C33A cells treated with wild-type FAT1 plasmid or FAT1 siRNA. Meanwhile, we evaluated the effect of FAT1 on the epithelial-mesenchymal transition (EMT) and the β-catenin-mediated transcription of target genes. Here, we showed that FAT1 expression was significantly lower in CC tissues than in adjacent tissues. FAT1 overexpression significantly dysregulated CC cell proliferation, invasion, and migration, whereas FAT1 knockdown had the opposite effect. FAT1 overexpression promoted the expression of phosphorylated β-catenin and E-cadherin protein and inhibited the expression of vimentin, TWIST, and several downstream targets of β-catenin, namely, c-MYC, TCF-4 and MMP14. In contrast, FAT1 silencing notably increased the expression c-MYC, TCF-4, and MMP14 and promoted the EMT in HeLa and C33A cells. Endogenous and exogenous FAT1 was confirmed to interact with β-catenin, and the overexpression of β-catenin could partially block the effect of FAT1 on the proliferation, migration, and invasion of HeLa and C33A cells. Conclusion: FAT1 acts as a tumor suppressor by inhibiting β-catenin-mediated transcription and might be used as a novel anti-metastatic agent in targeted CC therapy.

Molecular mechanistic insights: The emerging role of SOXF transcription factors in tumorigenesis and development

Over the last decade, the development and progress of next-generation sequencers incorporated with classical biochemical analyses have drastically produced novel insights into transcription factors, including Sry-like high-mobility group box (SOX) factors. In addition to their primary functions in binding to and activating specific downstream genes, transcription factors also participate in the dedifferentiation or direct reprogramming of somatic cells to undifferentiated cells or specific lineage cells. Since the discovery of SOX factors, members of the SOXF (SOX7, SOX17, and SOX18) family have been identified to play broad roles, especially with regard to cardiovascular development. More recently, SOXF factors have been recognized as crucial players in determining the cell fate and in the regulation of cancer cells. Here, we provide an overview of research on the mechanism by which SOXF factors regulate development and cancer, and discuss their potential as new targets for cancer drugs while offering insight into novel mechanistic transcriptional regulation during cell lineage commitment.

Association of C8orf4 expression with its methylation status, aberrant β-catenin expression, and the development of cervical squamous cell carcinoma

Chromosome 8 open reading frame 4 (C8orf4) is an activator of Wnt signaling pathway, and participates in the tumorigenesis and progression of many tumors. The expression levels of C8orf4 and β-catenin were assessed via immunohistochemical staining in 100 cervical squamous cell carcinoma (CSCC) tissues, 50 high-grade squamous intraepithelial lesions (HSILs), 50 low-grade squamous intraepithelial lesions (LSILs), and 50 normal cervical tissues. Bisulfite sequencing polymerase chain reaction analysis was used to examine the methylation status of the C8orf4 locus in CSCC and normal cervical tissues. The expression rates of C8orf4 and β-catenin were significantly higher in CSCCs or HSILs than in LSILs or normal cervical tissues (P < .05). C8orf4 expression was positively correlated with the poor differentiation of CSCCs (P = .009), and with aberrant expression of β-catenin in CSCCs (P = .002) and squamous intraepithelial lesions (P < .001). The methylation rate of C8orf4 in CSCCs was significantly lower than that in normal cervical tissues (P = .001). The Cancer Genome Atlas genomics data also confirmed that the mRNA expression of C8orf4 was positively associated with the copy number alteration of C8orf4 (correlation coefficient = 0.213, P < .001), and negatively correlated with the methylation level of C8orf4 (correlation coefficient = -0.408, P < .001). In conclusion, the expressions of C8orf4 and β-catenin were synergistically increased in CSCCs and HSILs and higher than those in LSILs and normal cervical tissues. The methylation level of C8orf4 is decreased in CSCCs and is responsible for the increased expression of C8orf4.

The role of SOX family members in solid tumours and metastasis

Cancer is a heavy burden for humans across the world with high morbidity and mortality. Transcription factors including sex determining region Y (SRY)-related high-mobility group (HMG) box (SOX) proteins are thought to be involved in the regulation of specific biological processes. The deregulation of gene expression programs can lead to cancer development. Here, we review the role of the SOX family in breast cancer, prostate cancer, renal cell carcinoma, thyroid cancer, brain tumours, gastrointestinal and lung tumours as well as the entailing therapeutic implications. The SOX family consists of more than 20 members that mediate DNA binding by the HMG domain and have regulatory functions in development, cell-fate decision, and differentiation. SOX2, SOX4, SOX5, SOX8, SOX9, and SOX18 are up-regulated in different cancer types and have been found to be associated with poor prognosis, while the up-regulation of SOX11 and SOX30 appears to be favourable for the outcome in other cancer types. SOX2, SOX4, SOX5 and other SOX members are involved in tumorigenesis, e.g. SOX2 is markedly up-regulated in chemotherapy resistant cells. The SoxF family (SOX7, SOX17, SOX18) plays an important role in angio- and lymphangiogenesis, with SOX18 seemingly being an attractive target for anti-angiogenic therapy and the treatment of metastatic disease in cancer. In summary, SOX transcription factors play an important role in cancer progression, including tumorigenesis, changes in the tumour microenvironment, and metastasis. Certain SOX proteins are potential molecular markers for cancer prognosis and putative potential therapeutic targets, but further investigations are required to understand their physiological functions.