RHBDD2­WWOX 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 domain­containing oxidoreductase (WWOX) protein. The present study characterized the RHBDD2­WWOX interaction in proliferating and differentiated stages of normal mammary and breast cancer cells by co­immunoprecipitation 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 co­precipitated with RHBDD2, indicating that endogenous RHBDD2 and WWOX were physically associated in normal and breast cancer proliferating cells compared with the differentiated stage. Co­localization assays corroborated the co­immunoprecipitation results, demonstrating the RHBDD2­WWOX protein interaction in normal and proliferating breast cancer cells. RHBDD2 harbors a conserved LPPY motif at the C­terminus region that directly interacted with the WW domains of WWOX. Since WWOX serves as an inhibitor of the TGFß/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 SMAD3­regulated genes were detected in proliferating cells compared with their differentiated counterparts. Follistatin and angiopoietin­like 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.

Effects of trichostatin A on FHIT and WWOX genes expression, cell growth inhibition and apoptosis induction in hepatocellular carcinoma WCH 17 cell line

Previously, we evaluated the effect of trichostatin A (TSA) on the expression of DNA methyltransferase 1 (DNMT1) in Hepatocellular Carcinoma (HCC). Fragile histidine triad (FHIT) and WW domain-containing oxidoreductase (WWOX) are two of the most common down-regulated genes in many cancers located on chromosome 3p14.2 and 16q23.3-24.1 respectively. The aim of the current study was to assess the effect of TSA on these genes expression, cell growth, and apoptosis in HCC WCH 17 cell. The cells were seeded and treated with TSA at different times. Then, MTT assay, flow cytometry, and qRT-PCR were achieved to determine viability, apoptosis and gene expression respectively. Cell growth was significantly inhibited, 92 to 36% after 24 h, 86 to 28% after 48 h, and 78 to 24% after 72 h. The results of flow cytometry confirmed that TSA increased apoptosis compared to the control group, the apoptosis percentage increased to 12%, 16%, and 18% in comparison to control groups (2%). Significant up-regulation of the genes was observed in all treated groups. We concluded that re-expression of silenced WWOX and FHIT genes could be achieved by TSA resulting in cell growth inhibition and apoptosis induction in WCH 17 cell.

Immunohistochemical WWOX expression and association with angiogenesis, p53 expression, cell proliferation and clinicopathological parameters in cervical cancer / Avaliação da expressão do gene WWOX por avaliação imunohistoquímica, sua associação com marcador de angiogênese, expressão do p53, proliferação celular e parâmetros clinicopatológicos no câncer de colo uterino

Abstract Objective The current study evaluated the expression of WW domain-containing oxidoreductase (WWOX), its association with clinicopathological features and with p53, Ki-67 (cell proliferation) and CD31 (angiogenesis) expression in patients with invasive cervical squamous cell carcinoma (ICSCC). To the best of our knowledge, no other study has evaluated this association. Methods Women with IB stage-ICSCC (n = 20) and women with uterine leiomyoma (n = 20) were prospectively evaluated. Patients with ICSCC were submitted to type BC1 radical hysterectomy and pelvic lymphadenectomy. Patients in the control group underwent vaginal hysterectomy. Tissue samples were stained with hematoxylin and eosin for histological evaluation and protein expression was detected by immunohistochemistry studies. Results The WWOX expression was significantly lower in the tumor compared with the expression in thebenign cervix (p = 0.019). TheWWOXexpressionwas inversely associated with the CD31 expression in the tumor samples (p = 0.018). There was no association betweentheWWOXexpression with the p53 expression (p = 0.464)or the Ki-67expression (p = 0.360) in the samples of invasive carcinoma of the cervix. There was no association between the WWOX expression and tumor size (p = 0.156), grade of differentiation (p = 0.914), presence of lymphatic vascular invasion (p = 0.155), parametrium involvement (p = 0.421) or pelvic lymph node metastasis (p = 0.310) in ICSCC tissue samples. Conclusion The results suggested that WWOX may be involved in ICSCC carcinogenesis, and this marker was associated with tumor angiogenesis.

Resumo Objetivo O presente estudo avaliou a expressão do WWOX, sua associação com características clinicopatológicas e com a expressão do p53, ki-67 (proliferação celular) e CD31 (angiogênese) em pacientes com carcinoma invasivo de células escamosas do colo uterino, ou simplesmente câncer do colo uterino (CCE). Métodos Foram avaliadas prospectivamente pacientes com CCE no estágio IB (n = 20) e mulheres com mioma uterino, no grupo controle (n = 20). As pacientes com CCE foram submetidas à histerectomia radical e à linfadenectomia pélvica do tipo B-C1. As mulheres no grupo-controle foram submetidas à histerectomia vaginal. As amostras de tecido foramcoradas comhematoxilina e eosina para avaliação histológica e a expressão das proteínas foi detectada por imuno-histoquímico. Resultados A expressão do WWOX foi significativamente menor no tumor quando comparada com sua expressão no colo do útero benigno (p = 0,019). A expressão tumoral de CD31 foi inversamente associada à expressão de WWOX (p = 0,018). Sua expressão não foi associada à expressão tumoral de p53 e Ki-67 em pacientes com CCE (p = 0,464 e p = 0,360, respectivamente). Não houve associação entre a expressão de WWOX e o tamanho do tumor (p = 0,156), grau de diferenciação (p = 0,914), presença de invasão vascular linfática (p = 0,155), comprometimento do paramétrio (p = 0,421) ou metástase dos linfonodos pélvicos (p = 0,310) em pacientes com CCE. Conclusão Os resultados sugeriram que o WWOX pode estar envolvido na carcinogênese do CICECU e esse marcador foi associado à angiogênese tumoral.

Immunohistochemical WWOX Expression and Association with Angiogenesis, p53 Expression, Cell Proliferation and Clinicopathological Parameters in Cervical Cancer.

OBJECTIVE: The current study evaluated the expression of WW domain-containing oxidoreductase (WWOX), its association with clinicopathological features and with p53, Ki-67 (cell proliferation) and CD31 (angiogenesis) expression in patients with invasive cervical squamous cell carcinoma (ICSCC). To the best of our knowledge, no other study has evaluated this association. METHODS: Women with IB stage-ICSCC (n = 20) and women with uterine leiomyoma (n = 20) were prospectively evaluated. Patients with ICSCC were submitted to type B-C1 radical hysterectomy and pelvic lymphadenectomy. Patients in the control group underwent vaginal hysterectomy. Tissue samples were stained with hematoxylin and eosin for histological evaluation and protein expression was detected by immunohistochemistry studies. RESULTS: The WWOX expression was significantly lower in the tumor compared with the expression in the benign cervix (p = 0.019). The WWOX expression was inversely associated with the CD31 expression in the tumor samples (p = 0.018). There was no association between the WWOX expression with the p53 expression (p = 0.464) or the Ki-67 expression (p = 0.360) in the samples of invasive carcinoma of the cervix. There was no association between the WWOX expression and tumor size (p = 0.156), grade of differentiation (p = 0.914), presence of lymphatic vascular invasion (p = 0.155), parametrium involvement (p = 0.421) or pelvic lymph node metastasis (p = 0.310) in ICSCC tissue samples. CONCLUSION: The results suggested that WWOX may be involved in ICSCC carcinogenesis, and this marker was associated with tumor angiogenesis.

OBJETIVO: O presente estudo avaliou a expressão do WWOX, sua associação com características clinicopatológicas e com a expressão do p53, ki-67 (proliferação celular) e CD31 (angiogênese) em pacientes com carcinoma invasivo de células escamosas do colo uterino, ou simplesmente câncer do colo uterino (CCE). MéTODOS: Foram avaliadas prospectivamente pacientes com CCE no estágio IB (n = 20) e mulheres com mioma uterino, no grupo controle (n = 20). As pacientes com CCE foram submetidas à histerectomia radical e à linfadenectomia pélvica do tipo B-C1. As mulheres no grupo-controle foram submetidas à histerectomia vaginal. As amostras de tecido foram coradas com hematoxilina e eosina para avaliação histológica e a expressão das proteínas foi detectada por imuno-histoquímico. RESULTADOS: A expressão do WWOX foi significativamente menor no tumor quando comparada com sua expressão no colo do útero benigno (p = 0,019). A expressão tumoral de CD31 foi inversamente associada à expressão de WWOX (p = 0,018). Sua expressão não foi associada à expressão tumoral de p53 e Ki-67 em pacientes com CCE (p = 0,464 e p = 0,360, respectivamente). Não houve associação entre a expressão de WWOX e o tamanho do tumor (p = 0,156), grau de diferenciação (p = 0,914), presença de invasão vascular linfática (p = 0,155), comprometimento do paramétrio (p = 0,421) ou metástase dos linfonodos pélvicos (p = 0,310) em pacientes com CCE. CONCLUSãO: Os resultados sugeriram que o WWOX pode estar envolvido na carcinogênese do CICECU e esse marcador foi associado à angiogênese tumoral.

RUNX2 and WWOX genes as molecular biomarkers and candidates for targeted therapy in Egyptian patients with primary conventional osteosarcoma

Background: The conventional osteosarcoma (OS) is the commonest primary malignant, bone tumor with complex genomic profiles and poor survival. Runt-related transcription factor 2 (RUNX2) and WW domain containing oxidoreductase (WWOX) genes are implicated in normal osteogenesis as well as in the development of primary conventional OS. Methods: We retrospectively assessed protein and RNA expression of the RUNX2 and WWOX genes by quantitative real time PCR (qPCR) and immunohistochemistry (IHC) in 80 cases of primary OS and 20 normal control (NC) subjects. Proteins and RNA expression levels of both genes were correlated to clinico-pathological features of the patients, progression free and overall survival (PFS& OS) rates. Results: In OS, RUNX2 protein was detected in 72/80 (90%) cases compared to 4/20 (20%) NC samples (p. < 0.001) and RUNX2-RNA was up regulated (up to 103.2 folds) in 60/80 (75%) (p = 0.01). WWOX protein and RNA (up to 7.2 folds) were detected in all NC samples but in 24/80 (30%) and 20/80 (20%) OS cases; respectively (p. < 0.001 for each). The concordance between the RNA and protein expressions for RUNX2 and WWOX was significantly high (X_trend

WWOX expression in giant cell lesions of the jaws.

OBJECTIVE: To investigate WWOX messenger RNA (mRNA) transcriptional levels in giant cell lesions (GCLs) of the jaws and associate its expression with clinical parameters. STUDY DESIGN: In this pilot study, quantitative reverse-transcription polymerase chain reaction was performed to analyze WWOX expression in 6 central giant cell lesions (CGCLs) (including 2 aggressive), 5 peripheral giant cell lesions (PGCLs) and 1 cherubism sample. Immunohistochemistry was performed to confirm the localization of the Wwox protein. RESULTS: CGCL and PGCL showed an overall increased expression of WWOX, as did the cherubism case, but no differences were observed among the groups. Wwox was localized almost entirely to the cytoplasm of multinucleated giant cells, as well as in a few mononuclear cells. CGCL and PGCL showed higher expression of the WWOX mRNA than peripheral blood mononuclear cells. The 2 aggressive CGCL samples exhibited decreased WWOX expression. CONCLUSIONS: These results showed increased expression of WWOX mainly in non-aggressive GCLs of the jaws.

Impact of WWOX alterations on p73, ΔNp73, p53, cell proliferation and DNA ploidy in salivary gland neoplasms.

OBJECTIVE: WWOX gene is altered in a variety of neoplasms. Wwox is pro-apoptotic through interaction with p73 and may be involved in chromosomal stability by interaction with p73 and p53. The aims of this study were to characterize WWOX transcription, methylation status and immunoexpression in salivary neoplasms and to determine whether these were associated with p73, p53, cell proliferation and DNA ploidy. MATERIALS AND METHODS: Seven malignant and 21 benign fresh salivary neoplasms were included. WWOX expression was determined by RT-PCR and sequencing of transcripts, quantitative PCR and immunohistochemistry. Methylation-specific PCR was used to assess the methylation of its first exon. For p73, ΔNp73, p53 and ki67 immunohistochemistry and ploidy analysis, 29 malignant samples from archives were included. RESULTS: No consistent pattern of WWOX exon 1 methylation was found, but aberrant and novel transcripts were observed in 17/28 neoplasms; 55% of tumours showed reduced WWOX RNA. WWOX RNA levels were associated with p53 immunopositivity. Immunohistochemical Wwox expression did not correlate with methylation status, p53 or p73 expression or proliferation. p73, proliferation and DNA ploidy were associated with malignant phenotype. CONCLUSION: Aberrant WWOX transcription and decreased expression are frequent in salivary neoplasms and WWOX transcription is associated with p53 staining.

Evidence of molecular alterations in the tumour suppressor gene WWOX in benign and malignant bone related lesions of the jaws.

WWOX is a tumour suppressor gene altered in various human neoplasms. Deletion of WWOX is associated with bone metabolic defects and development of osteosarcoma in mice. We hypothesized that alterations of this gene are associated with the development of benign and malignant mesenchymal bone related lesions of the jaws. We investigated WWOX mRNA by nested reverse transcription-PCR and direct sequencing and quantitative real-time PCR in two osteosarcoma, two fibrosarcoma, eight ossifying fibroma and two fibrous dysplasia fresh samples. Malignancy was associated with a decreased WWOX mRNA expression. Aberrant transcription pattern was found in five samples; however, the relative quantification (RQ) of the WWOX mRNA in such lesions was not different from those carrying only the wild-type. We provide new evidence of WWOX alterations in osteosarcomas and demonstrate for the first time alterations of this gene in fibrosarcomas as well as in ossifying fibromas of the jaws.

WW-domain-containing oxidoreductase is associated with low plasma HDL-C levels.

Low serum HDL-cholesterol (HDL-C) is a major risk factor for coronary artery disease. We performed targeted genotyping of a 12.4 Mb linked region on 16q to test for association with low HDL-C by using a regional-tag SNP strategy. We identified one SNP, rs2548861, in the WW-domain-containing oxidoreductase (WWOX) gene with region-wide significance for low HDL-C in dyslipidemic families of Mexican and European descent and in low-HDL-C cases and controls of European descent (p = 6.9 x 10(-7)). We extended our investigation to the population level by using two independent unascertained population-based Finnish cohorts, the cross-sectional METSIM cohort of 4,463 males and the prospective Young Finns cohort of 2,265 subjects. The combined analysis provided p = 4 x 10(-4) to 2 x 10(-5). Importantly, in the prospective cohort, we observed a significant longitudinal association of rs2548861 with HDL-C levels obtained at four different time points over 21 years (p = 0.003), and the T risk allele explained 1.5% of the variance in HDL-C levels. The rs2548861 resides in a highly conserved region in intron 8 of WWOX. Results from our in vitro reporter assay and electrophoretic mobility-shift assay demonstrate that this region functions as a cis-regulatory element whose associated rs2548861 SNP has a specific allelic effect and that the region forms an allele-specific DNA-nuclear-factor complex. In conclusion, analyses of 9,798 subjects show significant association between HDL-C and a WWOX variant with an allele-specific cis-regulatory function.

Molecular alterations in the tumor suppressor gene WWOX in oral leukoplakias.

Oral leukoplakia is the most prevalent and potentially malignant disorder of the oral mucosa. Previous studies have demonstrated that molecular changes of the WWOX gene (WW-domain containing oxidoreductase), a candidate tumor suppressor gene located at 16q23.3-24.1 that spans FRA16D, the second most common fragile site, are present in several malignant neoplasias, including oral squamous cell carcinoma. In this report, the role of the WWOX gene was investigated in 23 cases of oral leukoplakias. Using nested RT-PCR and immunohistochemistry, altered mRNA transcription and/or reduced Wwox protein expression was observed in 35% of the lesions when compared with normal mucosa. The majority of lesions (4/6) with altered transcripts had a reduction in the expression of Wwox protein. Although normal WWOX expression was found in some lesions with dysplasia, all lesions with WWOX mRNA and/or protein expression showed histological evidence of dysplasia and none of the cases without dysplasia presented this alteration. These results show that the WWOX gene alteration is an early genetic alteration and may contribute to oral carcinogenesis.

Association between decreased WWOX protein expression and thyroid cancer development.

CONTEXT: Chromosomal fragile sites are often related to cancer development. The WW domain-containing oxidoreductase gene (WWOX) spans the second most common chromosomal fragile site (FRA16D) and encodes an important proapoptotic protein. OBJECTIVE: To verify our hypothesis that underexpression of WWOX could contribute to malignant transformation of the thyroid cells. METHOD: We compared WWOX expression among follicular adenomas (FAs) and differentiated thyroid carcinomas [follicular thyroid carcinomas (FTCs) and papillary thyroid carcinomas (PTCs)] in 53 thyroid tumors resected from patients submitted to total thyroidectomy. DESIGN: Multiple fields of tumor areas of FAs, FTCs, and PTCs as well as normal thyroid tissue were stained with WWOX antiserum, and classified by the extent of staining (percentage of cells staining) and staining intensity. MAIN OUTCOME: PTCs showed a significantly decreased expression of WWOX when compared to FAs and FTCs. Further, using a unique model of comparison in patients in whom FAs and PTCs were concomitantly present, we detected the same result (i.e., no expression in PTCs). CONCLUSION: We conclude that WWOX underexpression is an important step that might increase the vulnerability to the carcinogenesis process in PTCs.

Characterization of the tumor suppressor gene WWOX in primary human oral squamous cell carcinomas.

Oral squamous cell carcinoma (OSCC) is the most common malignant neoplasm of the oral cavity, representing 90% of all oral carcinomas and accounting for 3-5% of all malignancies. The WWOX gene (WW-domain containing oxidoreductase) is a candidate tumor suppressor gene located at 16q23.3-24.1, spanning the second most common fragile site, FRA16D. In this report, the role of the WWOX gene was investigated in 20 tumors and 10 normal oral mucosas, and we demonstrated an altered WWOX gene in 50% (10/20) of OSCCs. Using nested RT-PCR, mRNA transcription was altered in 35% of the tumors, with the complete absence of transcripts in 2 samples as well as absence of exons 6-8 (2 tumors), exon 7 (1 tumor), exon 7 and exon 6-8 (1 tumor) and partial loss of exons 8 and 9 (1 tumor). To determine if the aberrant transcripts were translated, Western blots were performed in all samples; however, only the normal protein was detected. By immunohistochemistry, a reduction in Wwox protein expression was observed, affecting 40% of the tumors when compared with normal mucosa. In addition, a novel somatic mutation (S329F) was found. The presence of alterations in mRNA transcription correlated with the reduced expression of Wwox protein in the tumors. These results show that the WWOX gene is frequently altered in OSCC and may contribute to the carcinogenesis processes in oral cancer.