VOPP1 promotes breast tumorigenesis by interacting with the tumor suppressor WWOX

KLHDC7B as a novel diagnostic biomarker in urine exosomal mRNA promotes bladder urothelial carcinoma cell proliferation and migration, inhibits apoptosis

Bladder cancer is a common kind of urinary system cancer, in which bladder urothelial carcinoma (BLCA) comprises approximately 90% of all bladder cancer types. In our previous study, we discovered KLHDC7B in urine exosomal messenger RNA (mRNA) as a prospective molecular marker for bladder cancer detection. To systematically study the role and mechanism of KLHDC7B in BLCA, we focused on the most common type of BLCA in this study. First, we used RNA sequencing to discover that KLHDC7B was considerably increased in BLCA patients' urine exosomes compared to healthy controls. Then, we validated this result in an independent cohort and identified it as an effective tool for diagnosing and distinguishing high-grade and low-grade BLCA. Finally, we studied the role and mechanism of KLHDC7B in BLCA at the cellular level, providing a functional basis for its expression as a novel laboratory diagnostic biomarker for BLCA exosomal mRNA, which has important theoretical and clinical significance.

Molecular landscapes of glioblastoma cell lines revealed a group of patients that do not benefit from WWOX tumor suppressor expression

Introduction

Glioblastoma (GBM) is notorious for its clinical and molecular heterogeneity, contributing to therapeutic failure and a grim prognosis. WWOX is one of the tumor suppressor genes important in nervous tissue or related pathologies, which was scarcely investigated in GBM for reliable associations with prognosis or disease progression despite known alterations. Recently, we observed a phenotypic heterogeneity between GBM cell lines (U87MG, T98G, U251MG, DBTRG-05MG), among which the anti-GBM activity of WWOX was generally corresponding, but colony growth and formation were inconsistent in DBTRG-05MG. This prompted us to investigate the molecular landscapes of these cell lines, intending to translate them into the clinical context.

Methods

U87MG/T98G/U251MG/DBTRG-05MG were subjected to high-throughput sequencing, and obtained data were explored via weighted gene co-expression network analysis, differential expression analysis, functional annotation, and network building. Following the identification of the most relevant DBTRG-distinguishing driver genes, data from GBM patients were employed for, e.g., differential expression analysis, survival analysis, and principal component analysis.

Results

Although most driver genes were unique for each cell line, some were inversely regulated in DBTRG-05MG. Alongside driver genes, the differentially-expressed genes were used to build a WWOX-related network depicting protein-protein interactions in U87MG/T98G/U251MG/DBTRG-05MG. This network revealed processes distinctly regulated in DBTRG-05MG, e.g., microglia proliferation or neurofibrillary tangle assembly. POLE4 and HSF2BP were selected as DBTRG-discriminating driver genes based on the gene significance, module membership, and fold-change. Alongside WWOX, POLE4 and HSF2BP expression was used to stratify patients into cell lines-resembling groups that differed in, e.g., prognosis and treatment response. Some differences from a WWOX-related network were certified in patients, revealing genes that clarify clinical outcomes. Presumably, WWOX overexpression in DBTRG-05MG resulted in expression profile change resembling that of patients with inferior prognosis and drug response. Among these patients, WWOX may be inaccessible for its partners and does not manifest its anti-cancer activity, which was proposed in the literature but not regarding glioblastoma or concerning POLE4 and HSF2BP.

Conclusion

Cell lines data enabled the identification of patients among which, despite high expression of WWOX tumor suppressor, no advantageous outcomes were noted due to the cancer-promoting profile ensured by other genes.

WWOX binds MERIT40 and modulates its function in homologous recombination, implications in breast cancer

The tumor suppressor gene WWOX is localized in an unstable chromosomal region and its expression is decreased or absent in several types of cancer. A low expression of WWOX is associated with a poor prognosis in breast cancer (BC). It has recently been shown that WWOX contributes to genome stability through its role in the DNA damage response (DDR). In breast cancer cells, WWOX inhibits homologous recombination (HR), and thus promotes the repair of DNA double-stranded breaks (DSBs) by non-homologous end joining (NHEJ). The fine-tuning modulation of HR activity is crucial. Its under or overstimulation inducing genome alterations that can induce cancer. MERIT40 is a positive regulator of the DDR. This protein is indispensable for the function of the multi-protein complex BRCA1-A, which suppresses excessive HR activity. MERIT40 also recruits Tankyrase, a positive regulator of HR, to the DSBs to stimulate DNA repair. Here, we identified MERIT40 as a new molecular partner of WWOX. We demonstrated that WWOX inhibited excessive HR activity induced by overexpression of MERIT40. We showed that WWOX impaired the MERIT40-Tankyrase interaction preventing the role of the complex on DSBs. Furthermore, we found that MERIT40 is overexpressed in BC and that this overexpression is associated to a poor prognosis. These results strongly suggest that WWOX, through its interaction with MERIT40, prevents the deleterious impact of excessive HR on BC development by inhibiting MERIT40-Tankyrase association. This inhibitory effect of WWOX would oppose MERIT40-dependent BC development.

Antineoplastic Nature of WWOX in Glioblastoma Is Mainly a Consequence of Reduced Cell Viability and Invasion

Following the discovery of WWOX, research has moved in many directions, including the role of this putative tumor suppressor in the central nervous system and related diseases. The task of determining the nature of WWOX in glioblastoma (GBM) is still considered to be at the initial stage; however, the influence of this gene on the GBM malignant phenotype has already been reported. Because most of the available in vitro research does not consider several cellular GBM models or a wide range of investigated biological assays, the present study aimed to determine the main processes by which WWOX exhibits anticancer properties in GBM, while taking into account the phenotypic heterogeneity between cell lines. Ectopic WWOX overexpression was studied in T98G, DBTRG-05MG, U251MG, and U87MG cell lines that were compared with the use of assays investigating cell viability, proliferation, apoptosis, adhesion, clonogenicity, three-dimensional and anchorage-independent growth, and invasiveness. Observations presenting the antineoplastic properties of WWOX were consistent for T98G, U251MG, and U87MG. Increased proliferation and tumor growth were noted in WWOX-overexpressing DBTRG-05MG cells. A possible explanation for this, arrived at via bioinformatics tools, was linked to the TARDBP transcription factor and expression differences of USP25 and CPNE2 that regulate EGFR surface abundance. Collectively, and despite various cell line-specific circumstances, WWOX exhibits its anticancer nature mainly via a reduction of cell viability and invasiveness of glioblastoma.

Identification of Cross-Talk and Pyroptosis-Related Genes Linking Periodontitis and Rheumatoid Arthritis Revealed by Transcriptomic Analysis

BACKGROUND

The current study is aimed at identifying the cross-talk genes between periodontitis (PD) and rheumatoid arthritis (RA), as well as the potential relationship between cross-talk genes and pyroptosis-related genes.

METHODS

Datasets for the PD (GSE106090, GSE10334, GSE16134) and RA (GSE55235, GSE55457, GSE77298, and GSE1919) were downloaded from the GEO database. After batch correction and normalization of datasets, differential expression analysis was performed to identify the differentially expressed genes (DEGs). The cross-talk genes linking PD and RA were obtained by overlapping the DEGs dysregulated in PD and DEGs dysregulated in RA. Genes involved in pyroptosis were summarized by reviewing literatures, and the correlation between pyroptosis genes and cross-talk genes was investigated by Pearson correlation coefficient. Furthermore, the weighted gene coexpression network analysis (WGCNA) was carried out to identify the significant modules which contained both cross-talk genes and pyroptosis genes in both PD data and RA data. Thus, the core cross-talk genes were identified from the significant modules. Receiver-operating characteristic (ROC) curve analysis was performed to identify the predictive accuracy of these core cross-talk genes in diagnosing PD and RA. Based on the core cross-talk genes, the experimentally validated protein-protein interaction (PPI) and gene-pathway network were constructed.

RESULTS

A total of 40 cross-talk genes were obtained. Most of the pyroptosis genes were not differentially expressed in disease and normal samples. By selecting the modules containing both cross-talk genes or pyroptosis genes, the blue module was identified to be significant module. Three genes, i.e., cross-talk genes (TIMP1, LGALS1) and pyroptosis gene-GPX4, existed in the blue module of PD network, while two genes (i.e., cross-talk gene-VOPP1 and pyroptosis gene-AIM2) existed in the blue module of RA network. ROC curve analysis showed that three genes (TIMP1, VOPP1, and AIM2) had better predictive accuracy in diagnosing disease compared with the other two genes (LGALS1 and GPX4).

CONCLUSIONS

This study revealed shared mechanisms between RA and PD based on cross-talk and pyroptosis genes, supporting the relationship between the two diseases. Thereby, five modular genes (TIMP1, LGALS1, GPX4, VOPP1, and AIM2) could be of relevance and might serve as potential biomarkers. These findings are a basis for future research in the field.

Emerging a Novel VOPP1-EGFR Fusion Coexistent With T790M as an Acquired Resistance Mechanism to Prior Icotinib and Sensitive to Osimertinib in a Patient With EGFR L858R Lung Adenocarcinoma: A Case Report

Background

Epidermal growth factor receptor (EGFR) fusions are rare genomic events in non-small-cell lung cancer (NSCLC). Clinical support and evidence to guide management are absent for NSCLC patients harboring EGFR fusion.

Case Presentation

In this case report, we describe a 69-year-old female who received right lobectomy and was diagnosed with pathological stage IIIA lung adenocarcinoma harboring EGFR L858R. Twenty months later he had recurrent disease in the liver, lung, and bone, and was treated with icotinib. A novel vesicular overexpressed in cancer pro-survival protein 1 (VOPP1)-EGFR fusion gene coexistent with T790M were identified by next-generation sequencing using pericardial effusion and blood samples after icotinib treatment, which led to progression after icotinib six months and suggested a potential resistance mechanism. Subsequently, the patient was switched to osimertinib treatment, which resulted in a progression-free survival interval of more than 11 months.

Conclusions

The present results suggested that acquired VOPP1-EGFR fusion gene with T790M potentially serve an additional resistance mechanism to first-generation EGFR tyrosine kinase inhibitors in EGFR-mutated NSCLC. And the present case increases the evidence supporting use of osimertinib for treatment of NSCLC patients harboring EGFR fusion.

SLC38A4 functions as a tumour suppressor in hepatocellular carcinoma through modulating Wnt/β-catenin/MYC/HMGCS2 axis

BACKGROUND

Many molecular alterations are shared by embryonic liver development and hepatocellular carcinoma (HCC). Identifying the common molecular events would provide a novel prognostic biomarker and therapeutic target for HCC.

METHODS

Expression levels and clinical relevancies of SLC38A4 and HMGCS2 were investigated by qRT-PCR, western blot, TCGA and GEO datasets. The biological roles of SLC38A4 were investigated by functional assays. The downstream signalling pathway of SLC38A4 was investigated by qRT-PCR, western blot, immunofluorescence, luciferase reporter assay, TCGA and GEO datasets.

RESULTS

SLC38A4 silencing was identified as an oncofetal molecular event. DNA hypermethylation contributed to the downregulations of Slc38a4/SLC38A4 in the foetal liver and HCC. Low expression of SLC38A4 was associated with poor prognosis of HCC patients. Functional assays demonstrated that SLC38A4 depletion promoted HCC cellular proliferation, stemness and migration, and inhibited HCC cellular apoptosis in vitro, and further repressed HCC tumorigenesis in vivo. HMGCS2 was identified as a critical downstream target of SLC38A4. SLC38A4 increased HMGCS2 expression via upregulating AXIN1 and repressing Wnt/β-catenin/MYC axis. Functional rescue assays showed that HMGCS2 overexpression reversed the oncogenic roles of SLC38A4 depletion in HCC.

CONCLUSIONS

SLC38A4 downregulation was identified as a novel oncofetal event, and SLC38A4 was identified as a novel tumour suppressor in HCC.

Long non-coding RNA OIP5-AS1 promotes the progression of esophageal cancer by regulating miR-30a/VOPP1 expression

Long non-coding RNAs (lncRNAs) serve an important role in the development of esophageal cancer (EC), which is the eighth most common type of cancer worldwide. lncRNA opa-interacting protein 5 antisense transcript 1 (OIP5-AS1) is associated with human malignancy. However, the biological roles of OIP5-AS1 in the development of EC remain unclear. In the present study, transfection was conducted, and reverse transcription-quantitative PCR and western blot analysis were used for the detection of mRNA and protein expression, respectively. Furthermore, dual-luciferase reporter and RNA immunoprecipitation assays were used to study the interaction between miRNA and lncRNA or genes. The results revealed that OIP5-AS1 expression in EC tissues and cultured EC cells was upregulated, microRNA-30a (miR-30a) expression was downregulated. OIP5-AS1-knockdown suppressed the proliferation, migration and invasion of EC9706 and EC109 cells. miR-30a was confirmed to interact with OIP5-AS1, and miR-30a-mimics transfection ameliorated the effects of OIP5-AS1 in EC cells. Vesicular overexpressed in cancer prosurvival protein 1 (VOPP1) was verified as the direct target of miR-30a. VOPP1 expression was positively correlated with OIP5-AS1 expression in EC cells. Overexpression of VOPP1 ameliorated the negative effects of OIP5-AS1-knockdown on EC9706 and EC109 cells. In conclusion, OIP5-AS1 promoted the proliferation, migration and invasion of EC cells by increasing VOPP1 expression by sponging miR-30a.

RHBDD2‑WWOX protein interaction during proliferative and differentiated stages in normal and breast cancer cells

Rhomboid pseudoproteases are catalytically inactive members of the rhomboid superfamily that modulate the traffic, turnover and activity of their target proteins. Rhomboid domain containing 2 (RHBDD2) is a rhomboid family member overexpressed during mammary gland development and advanced stages of breast cancer. Interactome profiling studies have identified RHBDD2 as a novel binding partner of WW domain‑containing oxidoreductase (WWOX) protein. The present study characterized the RHBDD2‑WWOX interaction in proliferating and differentiated stages of normal mammary and breast cancer cells by co‑immunoprecipitation and confocal microscopy. Normal breast and proliferating cancer cells showed significantly increased RHBDD2 mRNA levels compared with their differentiated counterparts. WWOX mRNA was primarily expressed in differentiated cells. WWOX co‑precipitated with RHBDD2, indicating that endogenous RHBDD2 and WWOX were physically associated in normal and breast cancer proliferating cells compared with the differentiated stage. Co‑localization assays corroborated the co‑immunoprecipitation results, demonstrating the RHBDD2‑WWOX protein interaction in normal and proliferating breast cancer cells. RHBDD2 harbors a conserved LPPY motif at the C‑terminus region that directly interacted with the WW domains of WWOX. Since WWOX serves as an inhibitor of the TGFβ/SMAD3 signaling pathway in breast cells, modulation of SMAD3 target genes was analyzed in proliferating and differentiated mammary cells and in RHBDD2 silencing assays. Increased expression levels of SMAD3‑regulated genes were detected in proliferating cells compared with their differentiated counterparts. Follistatin and angiopoietin‑like 4 mRNA was significantly downregulated in RHBDD2 transiently silenced cells compared with scrambled control small interfering RNA. Based on these results, WWOX was suggested to be a novel RHBDD2 target protein involved in the modulation of breast epithelial cell proliferation and differentiation.

Molecular Functions of WWOX Potentially Involved in Cancer Development

The WW domain-containing oxidoreductase gene (WWOX) was cloned 21 years ago as a putative tumor suppressor gene mapping to chromosomal fragile site FRA16D. The localization of WWOX in a chromosomal region frequently altered in human cancers has initiated multiple current studies to establish its role in this disease. All of this work suggests that WWOX, due to its ability to interact with a large number of partners, exerts its tumor suppressive activity through a wide variety of molecular actions that are mostly cell specific.

Angiomotin Counteracts the Negative Regulatory Effect of Host WWOX on Viral PPxY-Mediated Egress

Filoviridae family members Ebola (EBOV) and Marburg (MARV) viruses and Arenaviridae family member Lassa virus (LASV) are emerging pathogens that can cause hemorrhagic fever and high rates of mortality in humans. A better understanding of the interplay between these viruses and the host will inform about the biology of these pathogens, and may lead to the identification of new targets for therapeutic development. Notably, expression of the filovirus VP40 and LASV Z matrix proteins alone drives assembly and egress of virus-like particles (VLPs). The conserved PPxY Late (L) domain motifs in the filovirus VP40 and LASV Z proteins play a key role in the budding process by mediating interactions with select host WW-domain containing proteins that then regulate virus egress and spread. To identify the full complement of host WW-domain interactors, we utilized WT and PPxY mutant peptides from EBOV and MARV VP40 and LASV Z proteins to screen an array of GST-WW-domain fusion proteins. We identified WW domain-containing oxidoreductase (WWOX) as a novel PPxY-dependent interactor, and we went on to show that full-length WWOX physically interacts with eVP40, mVP40 and LASV Z to negatively regulate egress of VLPs and of a live VSV/Ebola recombinant virus (M40). Interestingly, WWOX is a versatile host protein that regulates multiple signaling pathways and cellular processes via modular interactions between its WW-domains and PPxY motifs of select interacting partners, including host angiomotin (AMOT). Notably, we demonstrated recently that expression of endogenous AMOT not only positively regulates egress of VLPs, but also promotes egress and spread of live EBOV and MARV. Toward the mechanism of action, we show that the competitive and modular interplay among WWOX-AMOT-VP40/Z regulates VLP and M40 virus egress. Thus, WWOX is the newest member of an emerging group of host WW-domain interactors (e.g. BAG3; YAP/TAZ) that negatively regulate viral egress. These findings further highlight the complex interplay of virus-host PPxY/WW-domain interactions and their potential impact on the biology of both the virus and the host during infection.Author Summary Filoviruses (Ebola [EBOV] and Marburg [MARV]) and arenavirus (Lassa virus; LASV) are zoonotic, emerging pathogens that cause outbreaks of severe hemorrhagic fever in humans. A fundamental understanding of the virus-host interface is critical for understanding the biology of these viruses and for developing future strategies for therapeutic intervention. Here, we identified host WW-domain containing protein WWOX as a novel interactor with VP40 and Z, and showed that WWOX inhibited budding of VP40/Z virus-like particles (VLPs) and live virus in a PPxY/WW-domain dependent manner. Our findings are important to the field as they expand the repertoire of host interactors found to regulate PPxY-mediated budding of RNA viruses, and further highlight the competitive interplay and modular virus-host interactions that impact both the virus lifecycle and the host cell.

Cellular Expression and Subcellular Localization of Wwox Protein During Testicular Development and Spermatogenesis in Rats

A well-known putative tumor suppressor WW domain-containing oxidoreductase (Wwox) is highly expressed in hormonally regulated tissues and is considered important for the normal development and function of reproductive organs. In this study, we investigated the cellular and subcellular localization of Wwox in normal testes during postnatal days 0-70 using Western blotting and immunohistochemistry. Wwox is expressed in testes at all ages. Immunohistochemistry showed that fetal-type and adult-type Leydig cells, immature and mature Sertoli cells, and germ cells (from gonocytes to step 17 spermatids) expressed Wwox except peritubular myoid cells, step 18-19 spermatids, and mature sperm. Wwox localized diffusely in the cytoplasm with focal intense signals in all testicular cells. These signals gradually condensed in germ cells with their differentiation and colocalized with giantin for cis-Golgi marker and partially with golgin-97 for trans-Golgi marker. Biochemically, Wwox was detected in isolated Golgi-enriched fractions. But Wwox was undetectable in the nucleus. This subcellular localization pattern of Wwox was also confirmed in single-cell suspension. These findings indicate that Wwox is functional in most cell types of testis and might locate into Golgi apparatus via interaction with Golgi proteins. These unique localizations might be related to the function of Wwox in testicular development and spermatogenesis.

The role of vesicular overexpressed in cancer pro-survival protein 1 in hepatocellular carcinoma proliferation

BACKGROUND

Recently, hepatocellular carcinoma (HCC) has been ranked as the second leading cause of cancer-associated death. However, the underlying molecular mechanisms of HCC progression remain unclear. Vesicular overexpressed in cancer pro-survival protein 1 (VOPP1) could be upregulated in a quantity of human cancers, including squamous cell carcinoma (SCC), gastric cancer, and glioblastoma. However, the precise functional mechanism of VOPP1 in HCC remains poorly understood. The present study aimed to investigate the role of VOPP1 in HCC proliferation.

METHODS

Immunohistochemistry (IHC), Western blot and Reverse-transcription polymerase chain reaction (RT-PCR) were used to analyze the protein and mRNA expressions of VOPP1, mitogen-activated protein kinase (MAPK) 14, ribosomal protein S6 kinase β1 (RPS6KB1), cylindromatosis (CYLD) and Twist family bHLH transcription factor 1 (TWIST1). The cell proliferation and apoptosis were tested using Celigo cell imaging analyzer and annexin V-APC apoptosis detection kit respectively. Colony formation and tumor xenograft assays were performed to understand their roles in tumorigenicity.

RESULTS

The expression of VOPP1 in HCC samples was higher than that in adjacent noncancerous tissues by immunohistochemistry. In addition, the down-regulation of VOPP1 using shRNA inhibited cell proliferation and tumour growth, and induced cell apoptosis in vitro and in vivo. Furthermore, VOPP1 silencing increased the expression of MAPK14 and RPS6KB1, indicating that the MAPK and mTOR signalling pathways might be involved in VOPP1-mediated cancer cell proliferation.

CONCLUSION

The present data indicate that VOPP1 may play an important role in the progression of HCC by targeting the MAPK and mTOR signalling pathways, and that VOPP1 may potentially be a candidate as a novel molecular target for HCC therapy.

MiR-214 Mediates Cell Proliferation and Apoptosis of Nasopharyngeal Carcinoma Through Targeting Both WWOX and PTEN

Background: This study aimed to investigate interactions between miR-214, PTEN, and WWOX and their effect on AKT signaling during the NPC progression. Nasopharyngeal carcinoma (NPC) was highly prevalent with poor prognosis among the patients. MiR-214 reported as an important NPC biomarker was associated with regulation of biological functions.

Methods: 5–8F and 6–10B NPC cells were transfected with miR-214 inhibitor. MTT and colony formation assays were performed to assess cell proliferation. PI staining assay was performed to determine distribution of cell cycle. Annexin-V/PI staining assay was used to evaluate cell apoptosis in NPC. The effects of miR-214 inhibitor on the expression levels of PTEN, WWOX, AKT signaling pathway, cell-cycle-, and apoptosis-associated proteins were assessed by Western blotting or qRT-PCR assay. PTEN and WWOX were knocked down using the corresponding shRNA to investigate their effects on miR-214 inhibitor involved in proapoptosis and antiproliferation mechanisms in NPC.

Results: Inhibition of miR-214 suppressed cell growth and induced apoptosis of 5–8F and 6–10B cells. MiR-214 regulated the expression of both PTEN and WWOX through targeting the 3′-UTR. Inhibition of miR-214 promoted WWOX and PTEN expression, inactivated AKT signaling pathway, and regulated cell-cycle- and apoptosis-associated proteins. Knockdown of PTEN or WWOX reversed effects of miR-214 inhibitor on AKT signaling, cell proliferation, and apoptosis.

Conclusion: MiR-214 was suggested to induce cell proliferation and inhibit cell apoptosis of NPC through directly targeting both PTEN and WWOX, which provided a novel therapeutic target for clinical treatment of NPC.

LINC01410 Knockdown Suppresses Cervical Cancer Growth and Invasion via Targeting miR-2467-3p/VOPP1 Axis

Background

Long noncoding RNAs have essential roles in human diseases, including cancer. Our work aims to assess the function and mechanisms of LINC01410 in cervical cancer (CC) development.

Methods

Expression analyses were performed using qRT-PCR. Proliferation was determined through CCK8 and colony formation assays. Cell migration and invasion were determined by Transwell assay. The interactions among LINC01410, miR-2467-3p and VOPP1 were analyzed via luciferase reporter assay.

Results

LINC01410 was upregulated in CC tissues and cell lines. LINC01410 upregulation correlated with poor prognosis. LINC01410 silencing suppressed proliferation, migration and invasion of CC cells. LINC01410 was the sponge for miR-2467. And LINC01410 promoted VOPP1 expression through inhibiting miR-2467.

Conclusion

Our findings demonstrated that LINC01410 contributed to CC progression through regulating miR-2467/VOPP1 axis and suggested that LINC01410/miR-2467/VOPP1 cascade may be a potential therapeutic target.

Comprehensive identification and characterization of somatic copy number alterations in triple‑negative breast cancer

Triple‑negative breast cancer (TNBC) accounts for ~15% of all breast cancer diagnoses each year. Patients with TNBC tend to have a higher risk for early relapse and a worse prognosis. TNBC is characterized by extensive somatic copy number alterations (CNAs). However, the DNA CNA profile of TNBC remains to be extensively investigated. The present study assessed the genomic profile of CNAs in 201 TNBC samples, aiming to identify recurrent CNAs that may drive the pathogenesis of TNBC. In total, 123 regions of significant amplification and deletion were detected using the Genomic Identification of Significant Targets in Cancer algorithm, and potential driver genes for TNBC were identified. A total of 31 samples exhibited signs of chromothripsis and revealed chromosome pulverization hotspot regions. The present study further determined 199 genomic locations that were significantly enriched for breakpoints, which indicated TNBC‑specific genomic instability regions. Unsupervised hierarchical clustering of tumors resulted in three main subgroups that exhibited distinct CNA profiles, which may reveal the heterogeneity of molecular mechanisms in TNBC subgroups. These results will extend the molecular understanding of TNBC and will facilitate the discovery of therapeutic and diagnostic target candidates.

A p53/TIAF1/WWOX triad exerts cancer suppression but may cause brain protein aggregation due to p53/WWOX functional antagonism

Background

Tumor suppressor WWOX physically binds p53 and TIAF1 and together induces apoptosis and tumor suppression. To understand the molecular action, here we investigated the formation of WWOX/TIAF1/p53 triad and its regulation of cancer cell migration, anchorage-independent growth, SMAD promoter activation, apoptosis, and potential role in neurodegeneration.

Methods

Time-lapse microscopy was used to measure the extent of cell migration. Protein/protein interactions were determined by co-immunoprecipitation, FRET microscopy, and yeast two-hybrid analysis. The WWOX/TIAF1/p53 triad-mediated cancer suppression was determined by measuring the extent of cell migration, anchorage-independent growth, SMAD promoter activation, and apoptosis. p53-deficient lung cancer cell growth in nude mice was carried out to assess the tumor suppressor function of ectopic p53 and/or WWOX.

Results

Wwox-deficient MEF cells exhibited constitutive Smad3 and p38 activation and migrated individually and much faster than wild type cells. TGF-β increased the migration of wild type MEF cells, but significantly suppressed Wwox knockout cell migration. While each of the triad proteins is responsive to TGF-β stimulation, ectopically expressed triad proteins suppressed cancer cell migration, anchorage-independent growth, and SMAD promoter activation, as well as caused apoptosis. The effects are due in part to TIAF1 polymerization and its retention of p53 and WWOX in the cytoplasm. p53 and TIAF1 were effective in suppressing anchorage-independent growth, and WWOX ineffective. p53 and TIAF1 blocked WWOX or Smad4-regulated SMAD promoter activation. WWOX suppressed lung cancer NCI-H1299 growth and inhibited splenomegaly by inflammatory immune response, and p53 blocked the event in nude mice. The p53/WWOX-cancer mice exhibited BACE upregulation, APP degradation, tau tangle formation, and amyloid β generation in the brain and lung.

Conclusion

The WWOX/TIAF1/p53 triad is potent in cancer suppression by blocking cancer cell migration, anchorage-independent growth and SMAD promoter activation, and causing apoptosis. Yet, p53 may functionally antagonize with WWOX. p53 blocks WWOX inhibition of inflammatory immune response induced by cancer, and this leads to protein aggregation in the brain as seen in the Alzheimer’s disease and other neurodegeneration.

Electronic supplementary material

The online version of this article (10.1186/s12964-019-0382-y) contains supplementary material, which is available to authorized users.

A long non-coding RNA TSLD8 inhibits hepatocellular carcinoma by stabilizing WWOX

The hepatocellular carcinoma (HCC) is a common and highly aggressive malignancy especially in China. Accumulating data have shown a critical role of long non-coding RNAs (lncRNAs) during cancer progression. However, the function of lncRNA TSLD8 remains elusive. By lncRNA profiling, we identify a novel lncRNA termed TSLD8 in HCC. TSLD8 expression is significantly lowered in HCC tissues and cell lines. TSLD8 facilitates migration and viability in SMMC-7721 and HepG2 cells. Furthermore, TSLD8 can interact with WWOX and protect WWOX from proteasome-mediated degradation. Using PuPGEA-based nanocomplex for gene delivery, we found that co-delivery of TSLD8 and WWOX may exhibit synergistic and additive effects to inhibit HCC progression. PuPGEA-based nanocomplex delivery does not substantially alter the blood chemistries (e.g. alkaline phosphatase, blood urea nitrogen, aspartate aminotransferase, alanine aminotransferase) or initiate immune responses implying a safe strategy. Collectively, our current study has identified a novel tumor suppressive lncRNA TSLD8 which exerts its tumor suppressive function by stabilizing WWOX. Co-delivery of TSLD8 and WWOX via PuPGEA-based nanocomplexes might provide promising therapeutics for eradicating HCC.

Delineating WWOX Protein Interactome by Tandem Affinity Purification-Mass Spectrometry: Identification of Top Interactors and Key Metabolic Pathways Involved

It has become clear from multiple studies that WWOX (WW domain-containing oxidoreductase) operates as a "non-classical" tumor suppressor of significant relevance in cancer progression. Additionally, WWOX has been recognized for its role in a much wider array of human pathologies including metabolic conditions and central nervous system related syndromes. A myriad of putative functional roles has been attributed to WWOX mostly through the identification of various binding proteins. However, the reality is that much remains to be learned on the key relevant functions of WWOX in the normal cell. Here we employed a Tandem Affinity Purification-Mass Spectrometry (TAP-MS) approach in order to better define direct WWOX protein interactors and by extension interaction with multiprotein complexes under physiological conditions on a proteomic scale. This work led to the identification of both well-known, but more importantly novel high confidence WWOX interactors, suggesting the involvement of WWOX in specific biological and molecular processes while delineating a comprehensive portrait of WWOX protein interactome. Of particular relevance is WWOX interaction with key proteins from the endoplasmic reticulum (ER), Golgi, late endosomes, protein transport, and lysosomes networks such as SEC23IP, SCAMP3, and VOPP1. These binding partners harbor specific PPXY motifs which directly interact with the amino-terminal WW1 domain of WWOX. Pathway analysis of WWOX interactors identified a significant enrichment of metabolic pathways associated with proteins, carbohydrates, and lipids breakdown. Thus, suggesting that WWOX likely plays relevant roles in glycolysis, fatty acid degradation and other pathways that converge primarily in Acetyl-CoA generation, a fundamental molecule not only as the entry point to the tricarboxylic acid (TCA) cycle for energy production, but also as the key building block for de novo synthesis of lipids and amino acids. Our results provide a significant lead on subsets of protein partners and enzymatic complexes with which full-length WWOX protein interacts with in order to carry out its metabolic and other biological functions while also becoming a valuable resource for further mechanistic studies.