Diverse effect of WWOX overexpression in HT29 and SW480 colon cancer cell lines

Anti-Proliferative and Pro-Apoptotic Effects of Digested Aglianico Grape Pomace Extract in Human Colorectal Cancer Cells

Grape pomace (GP)—the major by-product of winemaking processes—still contains bioactive molecules with known beneficial properties for human health, such as an antiradical scavenging activity or an antiproliferative activity of tumors. In vitro studies have demonstrated that GP polyphenols specifically influence colon cancer cell proliferation. In addition to previously published work, we tested the phenolic compounds of Aglianico GP following an in vitro simulated gastrointestinal digestion on colorectal cancer cell lines at different degrees of differentiation. Our experiments, using HT29 and SW480 cells, confirmed the anti-proliferative effect of GP gastrointestinal digested extract and provided intriguing insights on the way it influences the cancer cell features (i.e., viability, proliferation, and apoptosis). We observed that Aglianico GP extract showed a great ability to affect cell proliferation and apoptosis. Interestingly, both HT29 and SW480 cells produced a significant increase in Bax, and a significant increase in the Bax/Bcl-2 ratio and caspase-3. The gastrointestinal digested GP extract was previously characterized both for antioxidant activity and phenolic composition. As a result, the TPC and the antioxidant activity reached high values in the Aglianico GP digested extract, and the main compounds assessed by UHPLC-DAD were anthocyanins, phenolic acids, and flavonoids. This work shed light on the use of digested GP extract as a dietary ingredient, a very sustainable source of nutritional compounds with potential health benefits for colon cancer cell proliferation.

Gold Nanoparticles Synthesized with Common Mullein (Verbascum thapsus) and Castor Bean (Ricinus communis) Ethanolic Extracts Displayed Antiproliferative Effects and induced Caspase 3 Activity in Human HT29 and SW480 Cancer Cells

Gold nanoparticles (AuNPs) are promising nanomaterials exhibiting anti-cancer effects. Green AuNPs synthesis using plant extracts can be used to achieve stable and beneficial nanoparticles due to their content of bioactive compounds. This research aimed to synthesize and evaluate the antiproliferative and caspase-3 activity induction of green AuNPs synthesized with common mullein (V. thapsus) flowers (AuNPsME) and castor bean (R. communis) leaves (AuNPsCE) ethanolic extracts in human HT29 and SW480 colorectal cancer cells. Their effect was compared with chemically synthesized AuNPs (AuNPsCS). The extracts mainly contained p-coumaric acid (71.88–79.93 µg/g), ferulic acid (19.07–310.71 µg/g), and rutin (8.14–13.31 µg/g). The obtained nanoparticles presented typical FT-IR bands confirming the inclusion of polyphenols from V. thapsus and R. communis and spherical/quasi-spherical morphologies with diameters in the 20.06–37.14 nm range. The nanoparticles (20–200 µg/mL) showed antiproliferative effects in both cell lines, with AuNPsCE being the most potent (IC50 HT29: 110.10 and IC50SW480: 64.57 µg/mL). The AuNPsCS showed the lowest intracellular reactive oxygen species (ROS) generation in SW480 cells. All treatments induced caspase 3/7 activity to a similar or greater extent than 30 mM H2O2-treated cells. Results indicated the suitability of V. thapsus and R. communis extracts to synthesize AuNPs, displaying a stronger antiproliferative effect than AuNPsCS.

Survival of HT29 cancer cells is influenced by hepatocyte growth factor receptor inhibition through modulation of self-DNA-triggered TLR9-dependent autophagy response

HGFR activation drives the malignant progression of colorectal cancer, and its inhibition displays anti-autophagic activity. The interrelated role of HGFR inhibition and TLR9/autophagy signaling in HT29 cancer cells subjected to modified self-DNA treatments has not been clarified. We analyzed this complex interplay with cell metabolism and proliferation measurements, TLR9, HGFR and autophagy inhibitory assays and WES Simple Western blot-based autophagy flux measurements, gene expression analyses, immunocytochemistry, and transmission electron microscopy. The overexpression of MyD88 and caspase-3 was associated with enhanced HT29 cell proliferation, suggesting that incubation with self-DNAs could suppress the apoptosis-induced compensatory cell proliferation. HGFR inhibition blocked the proliferation-reducing effect of genomic and hypermethylated, but not that of fragmented DNA. Lowest cell proliferation was achieved with the concomitant use of genomic DNA, HGFR inhibitor, and chloroquine, when the proliferation stimulating effect of STAT3 overexpression could be outweighed by the inhibitory effect of LC3B, indicating the putative involvement of HGFR-mTOR-ULK1 molecular cascade in HGFR inhibitor-mediated autophagy. The most intense cell proliferation was caused by the co-administration of hypermethylated DNA, TLR9 and HGFR inhibitors, when decreased expression of both canonical and non-canonical HGFR signaling pathways and autophagy-related genes was present. The observed ultrastructural changes also support the context-dependent role of HGFR inhibition and autophagy on cell survival and proliferation. Further investigation of the influence of the studied signaling pathways and cellular processes can provide a basis for novel, individualized anti-cancer therapies.

Survival of HT29 Cancer Cells Is Affected by IGF1R Inhibition via Modulation of Self-DNA-Triggered TLR9 Signaling and the Autophagy Response

Purpose: In HT29 colon cancer cells, a close interplay between self-DNA-induced TLR9 signaling and autophagy response was found, with remarkable effects on cell survival and differentiation. IGF1R activation drives the development and malignant progression of colorectal cancer. IGF1R inhibition displays a controversial effect on autophagy. The interrelated roles of IGF1R inhibition and TLR9/autophagy signaling in HT29 cancer cells have not yet been clarified. In our study, we aimed to investigate the complex interplay of IGF1R inhibition and TLR9/autophagy signaling in HT29 cells. Methods: HT29 cells were incubated with tumor-originated self-DNA with or without inhibitors of IGF1R (picropodophyllin), autophagy (chloroquine), and TLR9 (ODN2088), respectively. Cell proliferation and metabolic activity measurements, direct cell counting, NanoString and Taqman gene expression analyses, immunocytochemistry, WES Simple Western blot, and transmission electron microscopy investigations were performed. Results: The concomitant use of tumor-derived self-DNA and IGF1R inhibitors displays anti-proliferative potential, which can be reversed by parallel TLR9 signaling inhibition. The distinct effects of picropodophyllin, ODN2088, and chloroquine per se or in combination on HT29 cell proliferation and autophagy suggest that either the IGF1R-associated or non-associated autophagy machinery is "Janus-faced" regarding its actions on cell proliferation. Autophagy, induced by different combinations of self-DNA and inhibitors is not sufficient to rescue HT29 cells from death but results in the survival of some CD133-positive stem-like HT29 cells. Conclusion: The creation of new types of combined IGF1R, autophagy, and/or TLR9 signaling inhibitors would play a significant role in the development of more personalized anti-tumor therapies for colorectal cancer.

WWOX Loses the Ability to Regulate Oncogenic AP-2γ and Synergizes with Tumor Suppressor AP-2α in High-Grade Bladder Cancer

The cytogenic locus of the WWOX gene overlaps with the second most active fragile site, FRA16D, which is present at a higher frequency in bladder cancer (BLCA) patients with smoking habit, a known risk factor of this tumor. Recently, we demonstrated the relevance of the role of WWOX in grade 2 BLCA in collaboration with two AP-2 transcription factors whose molecular actions supported or opposed pro-cancerous events, suggesting a distinct character. As further research is needed on higher grades, the aim of the present study was to examine WWOX-AP-2 functionality in grade 3 and 4 BLCA using equivalent in vitro methodology with additional transcriptome profiling of cellular variants. WWOX and AP-2α demonstrated similar anti-cancer functionality in most biological processes with subtle differences in MMP-2/9 regulation; this contradicted that of AP-2γ, whose actions potentiated cancer progression. Simultaneous overexpression of WWOX and AP-2α/AP-2γ revealed that single discrepancies appear in WWOX-AP-2α collaboration but only at the highest BLCA grade; WWOX-AP-2α collaboration was considered anti-cancer. However, WWOX only appeared to have residual activity against oncogenic AP-2γ in grade 3 and 4: variants with either AP-2γ overexpression alone or combined WWOX and AP-2γ overexpression demonstrated similar pro-tumoral behavior. Transcriptome profiling with further gene ontology certified biological processes investigated in vitro and indicated groups of genes consisting of AP-2 targets and molecules worth investigation as biomarkers. In conclusion, tumor suppressor synergism between WWOX and AP-2α is unimpaired in high-grade BLCA compared to intermediate grade, yet the ability of WWOX to guide oncogenic AP-2γ is almost completely lost.

Low dose of zearalenone elevated colon cancer cell growth through G protein-coupled estrogenic receptor

Colon cancer is one of the leading causes of cancer death worldwide. It is widely believed that environmental factors contribute to colon cancer development. Zearalenone (ZEA) is non-steroidal estrogenic mycotoxin that is widely found in the human diet and animal feeds. Most cancer studies of ZEA focused on estrogen sensitive cancers, while few focused on other types, such as colon cancer; despite the gastrointestinal tract being the first barrier exposed to food contaminants. This study investigated the stimulatory effects of ZEA on colon cancer cell lines and their underlying molecular mechanisms. ZEA promoted anchorage independent cell growth and cell cycle progression through promoting G1-to-S phase transition. Proliferative marker, cyclin D1 and Ki67 were found to be upregulated upon ZEA treatment. G protein-coupled estrogenic receptor 1 (GPER) protein expression was promoted upon ZEA treatment suggesting the involvement of GPER. The growth promoting effect mediated through GPER were suppressed by its antagonist G15. ZEA were found to promote the downstream parallel pathway, MAPK signaling pathway and Hippo pathway effector YAP1. Altogether, our observations suggest a novel mechanism by which ZEA could promote cancer growth and provide a new perspective on the carcinogenicity of ZEA.

In vitro and in silico assessment of the effect of WWOX expression on invasiveness pathways associated with AP-2 transcription factors in bladder cancer

BACKGROUND

WW Domain Containing Oxidoreductase (WWOX) belongs to the unusual tumor suppressors, whose molecular function is not fully understood in bladder cancer, especially regarding interaction with Activator Protein 2 (AP-2) α/γ transcription factors. Thus, using lentiviral systems we created an in vitro model overexpressing or downregulating WWOX in CAL-29 cell line to assess invasiveness pathways. Surprisingly, while WWOX overexpression was accompanied with increased expression of both AP-2 factors, its downregulation only affected AP-2α level but not AP-2γ which remained high.

METHODS

Using cellular models and unpaired t-test or Wilcoxon test, we investigated significant changes in biological processes: clonogenicity, extracellular matrix adhesion, metalloproteinases activity, 3D culture growth, proliferation, mitochondrial redox potential and invasiveness. Relative gene expression acquired through Real-Time qPCR has been analyzed by Welch's t-test. Additionally, using oncoprint analysis we distinguished groups for bioinformatics analyzes in order to perform a follow-up of in vitro experiments.

RESULTS

Downregulation of WWOX in bladder cancer cell line intensified ability of single cell to grow into colony, mitochondrial redox potential and proliferation rate. Moreover, these cells shown elevated pro-MMP-2/9 activity but reduced adhesion to collagen I or laminin I, as well as distinct 3D culture growth. Through global in silico profiling we determined that WWOX alters disease-free survival of bladder cancer patients and modulates vital processes through AP-2 downstream effectors.

CONCLUSIONS

Our research indicates that WWOX possesses tumor suppressor properties in bladder cancer but consecutive examination is required to entirely understand the contribution of AP-2γ or AP-2α.

Fragile Gene WWOX Guides TFAP2A/TFAP2C-Dependent Actions Against Tumor Progression in Grade II Bladder Cancer

INTRODUCTION

The presence of common fragile sites is associated with no-accidental chromosomal instability which occurs prior to carcinogenesis. The WWOX gene spans the second most active fragile site: FRA16D. Chromosomal breakage at this site is more common in bladder cancer patients who are tobacco smokers which suggests the importance of WWOX gene loss regarding bladder carcinogenesis. Tryptophan domains of WWOX are known to recognize motifs of other proteins such as AP-2α and AP-2γ allowing protein-protein interactions. While the roles of both AP-2 transcription factors are important for bladder carcinogenesis, their nature is different. Based on the literature, AP-2γ appears to be oncogenic, whereas AP-2α mainly exhibits tumor suppressor character. Presumably, the interaction between WWOX and both transcription factors regulates thousands of genes, hence the aim of the present study was to determine WWOX, AP-2α, and AP-2γ function in modulating biological processes of bladder cancer.

METHODS

RT-112 cell line (grade II bladder cancer) was subjected to two stable lentiviral transductions. Overall, this resulted in six variants to investigate distinct WWOX, AP-2α, or AP-2γ function as well as WWOX in collaboration with a particular transcription factor. Cellular models were examined with immunocytochemical staining and in terms of differences in biological processes using assays investigating cell viability, proliferation, apoptosis, adhesion, clonogenicity, migration, activity of metalloproteinases and 3D culture growth.

RESULTS

WWOX overexpression increased apoptosis but decreased cell viability, migration and large spatial colonies. AP-2α overexpression decreased tumor cell viability, migratory potential, matrix metalloproteinase-2 activity and clonogenicity. AP-2γ overexpression decreased matrix metalloproteinase-2 activity but increased wound healing, adhesion, clonogenicity and spatial colony formation. WWOX and AP-2α overexpression induced apoptosis but decreased cell viability, adhesion, matrix metalloproteinase-2 activity, overall number of cultured colonies and migration rate. WWOX and AP-2γ overexpression decreased tumor cell viability, proliferation potential, adhesion, clonogenicity and the ability to create spatial structures, but also increased apoptosis or migration rate.

CONCLUSION

Co-overexpression of WWOX with AP-2α or WWOX with AP-2γ resulted in a net anti-tumor effect. However, considering this research findings and the difference between AP-2α and AP-2γ, we suggest that this similarity is due to a divergent behavior of WWOX.

Wwox Deficiency Causes Downregulation of Prosurvival ERK Signaling and Abnormal Homeostatic Responses in Mouse Skin

Deficiency of tumor suppressor WW domain-containing oxidoreductase (WWOX) in humans and animals leads to growth retardation and premature death during postnatal developmental stages. Skin integrity is essential for organism survival due to its protection against dehydration and hypothermia. Our previous report demonstrated that human epidermal suprabasal cells express WWOX protein, and the expression is gradually increased toward the superficial differentiated cells prior to cornification. Here, we investigated whether abnormal skin development and homeostasis occur under Wwox deficiency that may correlate with early death. We determined that keratinocyte proliferation and differentiation were decreased, while apoptosis was increased in Wwox^–/– mouse epidermis and primary keratinocyte cultures and WWOX-knockdown human HaCaT cells. Without WWOX, progenitor cells in hair follicle junctional zone underwent massive proliferation in early postnatal developmental stages and the stem/progenitor cell pools were depleted at postnatal day 21. These events lead to significantly decreased epidermal thickness, dehydration state, and delayed hair development in Wwox^–/– mouse skin, which is associated with downregulation of prosurvival MEK/ERK signaling in Wwox^–/– keratinocytes. Moreover, Wwox depletion results in substantial downregulation of dermal collagen contents in mice. Notably, Wwox^–/– mice exhibit severe loss of subcutaneous adipose tissue and significant hypothermia. Collectively, our knockout mouse model supports the validity of WWOX in assisting epidermal and adipose homeostasis, and the involvement of prosurvival ERK pathway in the homeostatic responses regulated by WWOX.

The WWOX gene in brain development and pathology

Shortly after its discovery in 2000, WWOX was hailed as a tumor suppressor gene. In subsequent years of research, this function was confirmed indisputably. Majority of tumors show high rate of loss of heterozygosity and decreased expression of WWOX. Nevertheless, over the years, the range of its known functions, at the cellular, organ and system levels, has expanded to include metabolism and endocrine system control and CNS differentiation and functioning. Despite of its function as a tumor suppressor gene, WWOX genetic alternations were found in a number of metabolic and neural diseases. A lack of WWOX protein as a consequence of germline mutations results in brain development disturbances and malfunctions.

The role of cellular contact and TGF-beta signaling in the activation of the epithelial mesenchymal transition (EMT)

The epithelial mesenchymal transition (EMT) is one step in the process through which carcinoma cells metastasize by gaining the cellular mobility associated with mesenchymal cells. This work examines the dual influence of the TGF-β pathway and intercellular contact on the activation of EMT in colon (SW480) and breast (MCF7) carcinoma cells. While the SW480 population revealed an intermediate state between the epithelial and mesenchymal states, the MC7 cells exhibited highly adhesive behavior. However, for both cell lines, an exogenous TGF-β signal and a reduction in cellular confluence can push a subgroup of the population towards the mesenchymal phenotype. Together, these results highlight that, while EMT is induced by the synergy of multiple signals, this activation varies across cell types.

LJELSR: A Strengthened Version of JELSR for Feature Selection and Clustering

Feature selection and sample clustering play an important role in bioinformatics. Traditional feature selection methods separate sparse regression and embedding learning. Later, to effectively identify the significant features of the genomic data, Joint Embedding Learning and Sparse Regression (JELSR) is proposed. However, since there are many redundancy and noise values in genomic data, the sparseness of this method is far from enough. In this paper, we propose a strengthened version of JELSR by adding the L₁-norm constraint on the regularization term based on a previous model, and call it LJELSR, to further improve the sparseness of the method. Then, we provide a new iterative algorithm to obtain the convergence solution. The experimental results show that our method achieves a state-of-the-art level both in identifying differentially expressed genes and sample clustering on different genomic data compared to previous methods. Additionally, the selected differentially expressed genes may be of great value in medical research.

Aberrantly Expressed Genes and miRNAs in Slow Transit Constipation Based on RNA-Seq Analysis

Background

This study aims to identify the key genes and miRNAs in slow transit constipation (STC).

Methods

MRNA and miRNA expression profiling were obtained. Differentially expressed genes (DEGs) and miRNAs were identified followed by the regulatory network construction. Functional annotation analysis and protein-protein interaction (PPI) network were conducted. The electronic validation was performed.

Results

Hsa-miR-2116-3p, hsa-miR-3622a-5p, hsa-miR-424-5p, and hsa-miR-1273-3p covered most DEGs. HLA-DRB1, HLA-DRB5, C3, and ICAM were significantly involved in staphylococcus aureus infection. The PPI network generated several hub proteins including ZBTB16, FBN1, CCNF, and CDK1. Electronic validation of HLA-DRB1, PTGDR, MKI67, BIRC5, CCNF, and CDK1 was consistent with the RNA-sequencing analysis.

Conclusion

Our study might be helpful in understanding the pathology of STC at the molecular level.

LncRNA WWOX‑AS1 inhibits the proliferation, migration and invasion of osteosarcoma cells

Recently, numerous long non-coding (lnc)RNAs have been revealed as serving important roles in human gene regulation. Previous studies have suggested that aberrant expression of lncRNAs is associated with cancer progression and metastasis. Previous studies have also demonstrated that decreased expression of WW domain-containing oxidoreductase (WWOX) is associated with poor prognosis in numerous cancer types. However, the effect of WWOX antisense RNA 1 (WWOX-AS1) in the development of cancer remains unknown. The aim of the present study was to investigate the role of WWOX-AS1 in osteosarcoma. The expression levels of WWOX-AS1 in human osteosarcoma cell lines and a normal osteoblastic cell line were investigated using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The results revealed that WWOX-AS1 expression was downregulated in osteosarcoma tissues. Furthermore, the association between WWOX-AS1 and the prognosis of patients with osteosarcoma was investigated using Kaplan-Meier and log-rank tests. The results suggested that patients exhibiting high WWOX-AS1 expression demonstrated a greater overall survival compared with patients exhibiting low WWOX-AS1 expression. In addition, overexpression and knockdown of WWOX-AS1 was performed using transfection experiments and confirmed by RT-qPCR in MG63 and SAOS2 cells, respectively. The results demonstrated that WWOX-AS1 and WWOX expression were positively correlated. Furthermore, the results of the knockdown and overexpression functional experiments suggested that WWOX-AS1 overexpression inhibited the proliferation, migration and invasion of MG63 cells, and knockdown of WWOX-AS1 enhanced the proliferation, migration and invasion of MG63 cells in SAOS2 cells. In conclusion, the results of the present study suggested that WWOX-AS1 may represent a potential biomarker and therapeutic target for the treatment of osteosarcoma.

A new tumor suppressor lncRNA RP11-190D6.2 inhibits the proliferation, migration, and invasion of epithelial ovarian cancer cells

At present, a large number of long noncoding RNAs (lncRNAs) from the human genome have been discovered. Meanwhile, emerging evidence has indicated that lncRNAs could play a critical role in the regulation of cellular processes such as cancer progression and metastasis. However, the functions of some new lncRNAs in the complex transcriptional process are mostly unknown at present. Existing studies suggest that loss of WW domain-containing oxidoreductase (WWOX) expression is linked with poor prognosis in numerous cancers, including epithelial ovarian cancer (EOC). However, the functional role of its antisense transcript RP11-190D6.2 is not clear to date. In this study, WWOX antisense transcript RP11-190D6.2 was analyzed specifically in EOC cells using real-time polymerase chain reaction and gain-/loss-of-function studies. We found that RP11-190D6.2 expression was positively correlated with WWOX expression. The RP11-190D6.2 expression was markedly downregulated in tumor tissues compared with normal tissues, but the RP11-190D6.2 expression was significantly downregu-lated in four EOC cell lines compared with human ovarian surface epithelial cell line. RP11-190D6.2 overexpression resulted in the increase of WWOX expression, whereas its knockdown led to the decrease of WWOX expression. We also found that RP11-190D6.2 was restored by 5-aza-2′-deoxycytidine treatment in EOC. In addition, the RP11-190D6.2 overexpression and knockdown experiments revealed that RP11-190D6.2 overexpression inhibited proliferation, migration, and invasion abilities in HO8910-PM cells, whereas RP11-190D6.2 knockdown in HEY-A8 cells had the opposite effect. The analyses in EOC implicate that RP11-190D6.2 may play a pivotal role in the regulation of tumor metastasis, suggesting that RP11-190D6.2 may serve as a potential biomarker and therapeutic target for EOC.

An AMP-activated protein kinase-stabilizing peptide ameliorates adipose tissue wasting in cancer cachexia in mice

Cachexia represents a fatal energy-wasting syndrome in a large number of patients with cancer that mostly results in a pathological loss of skeletal muscle and adipose tissue. Here we show that tumor cell exposure and tumor growth in mice triggered a futile energy-wasting cycle in cultured white adipocytes and white adipose tissue (WAT), respectively. Although uncoupling protein 1 (Ucp1)-dependent thermogenesis was dispensable for tumor-induced body wasting, WAT from cachectic mice and tumor-cell-supernatant-treated adipocytes were consistently characterized by the simultaneous induction of both lipolytic and lipogenic pathways. Paradoxically, this was accompanied by an inactivated AMP-activated protein kinase (Ampk), which is normally activated in peripheral tissues during states of low cellular energy. Ampk inactivation correlated with its degradation and with upregulation of the Ampk-interacting protein Cidea. Therefore, we developed an Ampk-stabilizing peptide, ACIP, which was able to ameliorate WAT wasting in vitro and in vivo by shielding the Cidea-targeted interaction surface on Ampk. Thus, our data establish the Ucp1-independent remodeling of adipocyte lipid homeostasis as a key event in tumor-induced WAT wasting, and we propose the ACIP-dependent preservation of Ampk integrity in the WAT as a concept in future therapies for cachexia.

The influence of the WWOX gene on the regulation of biological processes during endometrial carcinogenesis

The purpose of the present study was to investigate the role of WW domain containing oxidoreductase (WWOX) downregulation in biological cancer-related processes in normal (non-malignant) and cancer endometrial cell lines. We created an in vitro model using the normal endometrial cell line, THESC, and 2 endometrial cancer cell lines with varying degrees of differentiation, the Ishikawa (well-differentiated) and the MFE296 (moderately differentiated) cells, in which the WWOX tumor suppressor gene was silenced using Gipz lentiviral shRNA. In this model, we examined the changes in invasiveness via biological assays, such as zymography, migration through a basement membrane, the adhesion of cells to extracellular matrix proteins, anchorage-independent growth and colony formation assay. We also evaluated the correlation between the mRNA expression of the WWOX gene and genes involved in the processes of carcinogenesis, namely catenin beta-1 (CTNNB1) and zinc finger E-box binding homeobox 1 (ZEB1) (gene transcription), cadherin 1 (CDH1) and ezrin (EZR) (cell adhesion), vimentin (VIM) (structural proteins), as well as phosphatase and tensin homolog (PTEN) (tumor suppression) and secreted protein, acidic, cysteine-rich (osteonectin) (SPARC) (SPARC) (cell growth regulation) by RT-qPCR. Downregulation of the WWOX gene in the moderately differentiated MFE296 cell line caused decreased migratory capacity, and a reduction of matrix metalloproteinase-2 (MMP-2) activity. However, these cells grew in semisolid medium and exhibited higher expression of CDH1 and EZR (cell adhesion) and secreted protein, acidic, cysteine-rich (osteonectin) (SPARC) (cell growth regulation). Moreover, in the well-differentiated endometrial cancer (Ishikawa) cell line, WWOX gene silencing resulted in an increased ability of the cells to proliferate indefinitely. Additionally, WWOX regulated changes in adhesion potential in both the normal and cancer cell lines. Our results suggest that the WWOX tumor suppressor gene modulated the processes of cell motility, cell adhesion, gene expression and remodeling in endometrial cell lines.

Tumor Suppressor WWOX Contributes to the Elimination of Tumorigenic Cells in Drosophila melanogaster

WWOX is a >1Mb gene spanning FRA16D Common Chromosomal Fragile Site, a region of DNA instability in cancer. Consequently, altered WWOX levels have been observed in a wide variety of cancers. In vitro studies have identified a large number and variety of potential roles for WWOX. Although its normal role in vivo and functional contribution to cancer have not been fully defined, WWOX does have an integral role in metabolism and can suppress tumor growth. Using Drosophila melanogaster as an in vivo model system, we find that WWOX is a modulator of TNFα/Egr-mediated cell death. We found that altered levels of WWOX can modify phenotypes generated by low level ectopic expression of TNFα/Egr and this corresponds to altered levels of Caspase 3 activity. These results demonstrate an in vivo role for WWOX in promoting cell death. This form of cell death is accompanied by an increase in levels of reactive oxygen species, the regulation of which we have previously shown can also be modified by altered WWOX activity. We now hypothesise that, through regulation of reactive oxygen species, WWOX constitutes a link between alterations in cellular metabolism observed in cancer cells and their ability to evade normal cell death pathways. We have further shown that WWOX activity is required for the efficient removal of tumorigenic cells from a developing epithelial tissue. Together these results provide a molecular basis for the tumor suppressor functions of WWOX and the better prognosis observed in cancer patients with higher levels of WWOX activity. Understanding the conserved cellular pathways to which WWOX contributes provides novel possibilities for the development of therapeutic approaches to restore WWOX function in cancer.

The role of WWOX tumor suppressor gene in the regulation of EMT process via regulation of CDH1-ZEB1-VIM expression in endometrial cancer

This study defines the role of WWOX in the regulation of epithelial to mesenchymal transition. A group of 164 endometrial adenocarcinoma patients was studied as well as an ECC1 well-differentiated steroid-responsive endometrial cell line, which was transducted with WWOX cDNA by a retroviral system. The relationship between WWOX gene and EMT marker (CDH1, VIM, ZEB1, SNAI1) expression on mRNA (RT-qPCR) and protein levels (western blotting) was evaluated. The EMT processes were also analysed in vitro by adhesion of cells to extracellular matrix proteins, migration through a basement membrane, anchorage-independent growth and MMP activity assay. DNA microarrays (HumanOneArray™) were used to determine WWOX-dependent pathways in an ECC1 cell line. A positive correlation was observed between WWOX and ZEB1, and a negative correlation between CDH1 and VIM. WWOX expression was found to inversely correlate with the risk of recurrence of tumors in patients. However, in the WWOX-expressing ECC1 cell line, WWOX expression was found to be inversely related with VIM and positively with CDH1. The ECC1/WWOX cell line variant demonstrated increased migratory capacity, with increased expression of metalloproteinases MMP2/MMP9. However, these cells were not able to form colonies in suspension and revealed decreased adhesion to fibronectin and fibrinogen. Microarray analysis demonstrated that WWOX has an impact on the variety of cellular pathways including the cadherin and integrin signalling pathways. Our results suggest that the WWOX gene plays a role in the regulation of EMT processes in endometrial cancer by controlling the expression of proteins associated with cell motility, thus influencing tissue remodeling, with the suppression of mesenchymal markers.

WWOX modulates the gene expression profile in the T98G glioblastoma cell line rendering its phenotype less malignant

The aim of the present study was to assess the influence of WWOX gene upregulation on the transcriptome and phenotype of the T98G glioblastoma cell line. The cells with high WWOX expression demonstrated a significantly different transcription profile for approximately 3,000 genes. The main cellular pathways affected were Wnt, TGFβ, Notch and Hedgehog. Moreover, the WWOX-transfected cells proliferated at less than half the rate, exhibited greatly lowered adhesion to ECM, increased apoptosis and impaired 3D culture formation. They also demonstrated an increased ability for crossing the basement membrane. Our results indicate that WWOX, apart from its tumor-suppressor function, appears to be a key regulator of the main cellular functions of the cell cycle and apoptosis. Furthermore, our results showed that WWOX may be involved in controlling metabolism, cytoskeletal structure and differentiation.