Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Wnt2 Protein”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 109 records · Page 6Linked to original sources
PubMed2004

Expression of Wnt genes and frizzled 1 and 2 receptors in normal breast epithelium and infiltrating breast carcinoma.

The Wnt genes encode a family of related, secreted proteins which initiate a signal cascade upon binding to cell surface receptor molecules. The signaling pathway has been shown to be critical for normal growth and development in model organisms and is implicated in the genesis of numerous human cancers. Wnt proteins regulate mammary development in the mouse but their precise role in normal breast development and malignant transformation in humans remains poorly defined. In this study, we have examined the expression of several Wnt ligands by in situ anti-sense RNA hybridization in normal and malignant human breast tissue, as well as in several estrogen-responsive and estrogen-independent human breast cancer cell lines. The specific Wnt genes tested included Wnt1, Wnt2, Wnt4, Wnt5a, Wnt5b, Wnt6, Wnt7b and Wnt10b. We have also studied the expression of frizzled receptors 1 and 2 by immunohistochemistry in these tissues. Our results indicate that several of the Wnt ligands, especially Wnt1 and Wnt6, are strongly expressed in both normal and malignant breast tissue and that Wnt7b is down-regulated in breast cancer, compared to normal breast epithelium. The expression of frizzled 1 and 2 receptors was found to be up-regulated in breast cancer. These studies provide additional support to the hypothesis that the Wnt signaling pathway is involved in human breast cancer.

Breast Neoplasms↗
PubMed2003

Cooperation between TGF-beta and Wnt pathways during chondrocyte and adipocyte differentiation of human marrow stromal cells.

UNLABELLED: Human marrow stromal cells have the potential to differentiate to chondrocytes or adipocytes. We show interactions between TGF-beta and Wnt signaling pathways during stimulation of chondrogenesis and inhibition of adipogenesis. Combining these signals may be useful in marrow stromal cell therapies. INTRODUCTION: Human bone marrow stromal cells (hMSCs) have the potential to differentiate to lineages of mesenchymal tissues, including cartilage, fat, bone, tendon, and muscle. Agents like transforming growth factor (TGF)-beta promote chondrocyte differentiation at the expense of adipocyte differentiation. In other processes, TGF-beta and Wnt/wingless signaling pathways play major roles in controling certain developmental events and activation of specific target genes. We tested whether these pathways interact during differentiation of chondrocytes and adipocytes in human marrow stromal cells. MATERIALS AND METHODS: Both a line of human marrow stromal cells (KM101) and freshly isolated hMSCs were studied. Reverse transcriptase-polymerase chain reaction (RT-PCR), Western blot, and macroarrays were used for analysis of the modulation of TGF-beta1 on Wnt signaling-associated genes, chondrocyte differentiation genes, and TGFbeta/bone morphogenetic protein (BMP) signaling-associated genes in KM101 cells. Early passage hMSCs obtained from 42- and 58-year-old women were used for the effects of TGF-beta and/or Wnt (mimicked by LiCl) signals on chondrocyte and adipocyte differentiation in two-dimensional (2-D) cultures, 3-D pellet cultures, and collagen sponges. RESULTS: As indicated by macroarray, RT-PCR, and Western blot, TGF-beta activated genes in the TGF-beta/Smad pathway, upregulated Wnt2, Wnt4, Wnt5a, Wnt7a, Wnt10a, and Wnt co-receptor LRP5, and increased nuclear accumulation and stability of beta-catenin in KM101 cells. TGF-beta upregulated chondrocyte gene expression in KM101 cells and also stimulated chondrocyte differentiation and inhibited adipocyte differentiation in hMSCs, synergistically with Wnt signal. Finally, hMSCs cultured in 3-D collagen sponges were stimulated by TGF-beta1 to express aggrecan and collagen type II mRNA, whereas expression of lipoprotein lipase was inhibited. CONCLUSIONS: In summary, TGF-beta stimulated chondrocyte differentiation and inhibited adipocyte differentiation of hMSCs in vitro. The activation of both TGF-beta and Wnt signal pathways by TGF-beta, and synergy between TGF-beta and Wnt signals, supports the view that Wnt-mediated signaling is one of the mechanisms of TGF-beta's effects on chondrocyte and adipocyte differentiation of hMSCs.

Adipocytes↗
PubMed1998

Differential expression of Wnt genes in normal and flat variants of PC12 cells, a cell line responsive to ectopic Wnt1 expression.

Wnt genes encode secreted growth factor-like proteins that participate in growth regulation, differentiation and tumorigenesis. Ectopic expression of Wnt1 converts the PC12 neural crest-derived rat pheochromocytoma cell line from a round phenotype that express chromaffin markers to flat adherent cells (termed PC12/Wnt1) that do not express them. A pool of spontaneously flat variants of PC12 cells (PC12/flat) is phenotypically similar to the PC12/Wnt1 cells, but does not express Wnt1. Here we describe the expression of 13 Wnt genes in wild type PC12, PC12/flat and PC12/Wnt1 cells. Wild type PC12 expressed Wnt3, Wnt3a, Wnt4, Wnt5a, Wnt6, Wnt10a and Wnt11. Compared with expression in wild type cells, both PC12/flat and PC12/Wnt1 cells lost most or all expression of Wnt3a and Wnt4 and gained expression of Wnt7b. Wnt5a and Wnt6 expression was higher in PC12/Wnt1 cells than in PC12 or PC12/flat. Wnt3 was expressed at low levels in both PC12 and PC12/flat, but was absent in PC12/Wnt1 cells. Wnt10a and Wnt11 were approximately equally expressed in the three groups, and Wnt2, Wnt5b, Wnt7a, Wnt10b and endogenous Wnt1 mRNAs were not detected. These results demonstrate that the expression of some Wnt genes changes in PC12 cells upon conversion to the flat phenotype, and suggest that Wnt1 may modulate expression of several other Wnt genes in these cells.

Animals↗
PubMed2004

Sonic hedgehog signaling regulates Gli3 processing, mesenchymal proliferation, and differentiation during mouse lung organogenesis.

Lack of Sonic hedgehog (Shh) signaling, mediated by the Gli proteins, leads to severe pulmonary hypoplasia. However, the precise role of Gli genes in lung development is not well established. We show Shh signaling prevents Gli3 proteolysis to generate its repressor forms (Gli3R) in the developing murine lung. In Shh(-/-) or cyclopamine-treated wild-type (WT) lung, we found that Gli3R level is elevated, and this upregulation appears to contribute to defects in proliferation and differentiation observed in the Shh(-/-) mesenchyme, where Gli3 is normally expressed. In agreement, we found Shh(-/-);Gli3(-/-) lungs exhibit enhanced growth potential. Vasculogenesis is also enhanced; in contrast, bronchial myogenesis remains absent in Shh(-/-);Gli3(-/-) compared with Shh(-/-) lungs. Genes upregulated in Shh(-/-);Gli3(-/-) relative to Shh(-/-) lung include Wnt2 and, surprisingly, Foxf1 whose expression has been reported to be Shh-dependent. Cyclins D1, D2, and D3 antibody labelings also reveal distinct expression patterns in the normal and mutant lungs. We found significant repression of Tbx2 and Tbx3, both linked to inhibition of cellular senescence, in Shh(-/-) and partial derepression in Shh(-/-); Gli3(-/-) lungs, while Tbx4 and Tbx5 expressions are less affected in the mutants. Our findings shed light on the role of Shh signaling on Gli3 processing in lung growth and differentiation by regulating several critical genes.

Animals↗
PubMed2005

Gene array analysis of Wnt-regulated genes in C3H10T1/2 cells.

Wnt/beta-catenin signaling is involved in a large variety of modeling and remodeling processes including cell polarity, cell differentiation, and cell migration. Recently, a role of the Wnt pathway in bone biology has been demonstrated. However, the precise mechanism by which Wnt proteins regulate bone formation still remains to be elucidated. We have previously shown that the Wnt pathway mediates induction of alkaline phosphatase, an osteoblast differentiation marker, in the pluripotent mesenchymal cells C3H10T1/2. In the present study, we performed a genome-wide expression analysis using Affymetrix oligonucleotide chips to determine the Wnt3a-induced gene expression profile in C3H10T1/2 cells. The expression profiles of 447 Wnt3a-regulated genes, classified into distinct functional families, are presented here. Our data reveal that Wnt3a regulates several genes that are involved in osteoblast and adipocyte differentiation. Importantly, Wnt3a induces the expression of osteoprotegerin by a beta-catenin dependent mechanism indicating that the Wnt pathway may also affect osteoclastogenesis. Through the analysis of our expression profiling data, we have established a TaqMan panel as a tool to rapidly compare the expression profiles of a specific set of genes induced by distinct stimuli acting in the Wnt/beta-catenin pathway. Using the TaqMan panel, we have compared the gene expression profiles induced by Wnt1, Wnt2, and Wnt3a in C3H10T1/2 cells, and also by two different GSK-3beta inhibitors: LiCl and SB216773. Our data show that Wnt1 and Wnt3a act in a similar manner, distinct from Wnt2. Finally, we found that LiCl and SB216773 displayed different profiles in the TaqMan panel evidencing their distinct inhibitory action toward GSK-3beta. Overall, data presented herein will aid further understanding of the involvement of the Wnt signaling pathway in its regulation of osteoblast and adipocyte differentiation and function and, in addition, will enhance current knowledge of the Wnt signaling pathway itself.

Animals↗
PubMed2005

Homologous feeder cells support undifferentiated growth and pluripotency in monkey embryonic stem cells.

In the present study, five homologous feeder cell lines were developed for the culture and maintenance of rhesus monkey embryonic stem cells (rESCs). Monkey ear skin fibroblasts (MESFs), monkey oviductal fibroblasts (MOFs), monkey follicular granulosa fibroblast-like (MFG) cells, monkey follicular granulosa epithelium-like (MFGE) cells, and clonally derived fibroblasts from MESF (CMESFs) were established and compared with the ability of mouse embryonic fibroblasts (MEFs) to support rESC growth. MESF, MOF, MFG, and CMESF cells, but not MFGE cells, were as good as or better than MEFs in supporting undifferentiated growth while maintaining the differentiation potential of the rESCs. In an effort to understand the unique properties of supportive feeder cells, expression levels for a number of candidate genes were examined. MOF, MESF, and MEF cells highly expressed leukemia inhibitory factor, ciliary neurotrophic factor, basic fibroblast growth factor, stem cell factor, transforming growth factor beta1, bone morphogenetic protein 4, and WNT3A, whereas WNT2, WNT4, and WNT5A were downregulated, compared with MFGE cells. Additionally, all monkey feeder cell lines expressed Dkk1 and LRP6, antagonists of the WNT signaling pathway, but not WNT1, WNT8B, or Dkk2. rESCs grown on homologous feeders maintained normal karyotypes, displayed the characteristics of ESCs, including morphology, alkaline phosphatase, Oct4, the cell surface markers stage-specific embryonic antigen (SSEA)-3, SSEA-4, tumor-related antigen (TRA)-1-60, and TRA-1-81, and formed cystic embryoid bodies in vitro that included differentiated cells representing the three major germ layers. These results indicate that the four homologous feeder cell lines can be used to support the undifferentiated growth and maintenance of pluripotency in rESCs.

Animals↗
PubMed2001

Evidence supporting WNT2 as an autism susceptibility gene.

We examined WNT2 as a candidate disease gene for autism for the following reasons. First, the WNT family of genes influences the development of numerous organs and systems, including the central nervous system. Second, WNT2 is located in the region of chromosome 7q31-33 linked to autism and is adjacent to a chromosomal breakpoint in an individual with autism. Third, a mouse knockout of Dvl1, a member of a gene family essential for the function of the WNT pathway, exhibits a behavioral phenotype characterized primarily by diminished social interaction. We screened the WNT2 coding sequence for mutations in a large number of autistic probands and found two families containing nonconservative coding sequence variants that segregated with autism in those families. We also identified linkage disequilibrium (LD) between a WNT2 3'UTR SNP and our sample of autism-affected sibling pair (ASP) families and trios. The LD arose almost exclusively from a subgroup of our ASP families defined by the presence of severe language abnormalities and was also found to be associated with the evidence for linkage to 7q from our previously published genomewide linkage screen. Furthermore, expression analysis demonstrated WNT2 expression in the human thalamus. Based on these findings, we hypothesize that rare mutations occur in the WNT2 gene that significantly increase susceptibility to autism even when present in single copies, while a more common WNT2 allele (or alleles) not yet identified may exist that contributes to the disorder to a lesser degree.

Amino Acid Sequence↗
PubMed2005

Classical genotropic versus kinase-initiated regulation of gene transcription by the estrogen receptor alpha.

Elucidation of kinase-initiated routes by which the estrogen receptors alpha and beta (ERalpha and ERbeta) control gene transcription, along with evidence of distinct biologic outcomes in response to ligands that can selectively activate nongenotropic signaling of the ERs or the androgen receptor, suggest that the ERs control a range of genes wider than that regulated by their direct association with DNA. To ascertain the extent and significance of nongenotropic ER-mediated transcription, we employed transduced HeLa cells expressing wild-type ERalpha or the ligand binding domain of ERalpha localized to the cell membrane (E-Mem), the OB-6 osteoblastic cell line, MCF-7 breast carcinoma cells and uteri from mice treated with 17beta-estradiol (E(2)), or the nongenotropic signaling activator 4-estren-3alpha,17beta-diol (estren). E(2) and estren induced ERK1/2 and Akt phosphorylation in ERalpha or E-Mem stably transfected HeLa cells; however, the phosphorylation kinetics differed between the two cell lines. In all four models, nongenotropic ER actions regulated a population of genes distinct from those regulated by genotropic ER actions. Specifically, the expression of Wnt2, Frizzled10, Egr-1, and c-Fos was strongly up-regulated in E-Mem-containing HeLa cells treated with E(2) or estren, or in ERalpha-containing HeLa cells treated with estren. Up-regulation of Frizzled10 by estren was reproduced in MCF-7 cells. Egr-1 was up-regulated by both estren and E(2); but complement 3, only by E(2) in the uteri. Estren had no effect on complement 3, cathepsin D, progesterone receptor, bcl-2, and cyclin D1 in MCF-7 cells, whereas E(2) up-regulated all these estrogen response element or activating protein-1-containing genes. These results support an extensive divergence in gene expression depending on the mode of ER activation.

Animals↗
PubMed2001

Frequent up-regulation of WNT2 in primary gastric cancer and colorectal cancer.

WNT2 is one of proto-oncogenes with the potential to activate the WNT - beta-catenin - TCF signaling pathway, which is most homologous to WNT2B among members of the human WNT gene family. Here, expression of WNT2 mRNA was comprehensively investigated. WNT2 mRNAs were highly expressed in fetal lung, and weakly expressed in placenta. Among 2.0-, 2.9-, 4.1-, and 6.0-kb WNT2 mRNAs, the 2.0-kb WNT2 mRNA was the major transcript in fetal lung. In 3 cases of prostate cancer and 1 case each of lung cancer and cervical cancer, WNT2 was over-expressed in non-cancerous portion as well as in primary tumor. WNT2 was up-regulated in 14 out of 18 cases of primary colorectal cancer, 4 out of 7 cases of uterus tumor, 2 out of 9 cases of breast cancer, and in 2 out of 14 cases of kidney tumor. Up-regulation of WNT2 was also detected in 4 out of 8 cases of primary gastric cancer by using expression array filter hybridization, and in 10 out of another 10 cases of primary gastric cancer by using cDNA-PCR. Frequent up-regulation of WNT2 in primary gastric cancer and colorectal cancer might play a key role in carcinogenesis through activation of the WNT - beta-catenin - TCF signaling pathway.

Colorectal Neoplasms↗
PubMed2003

MultiPipMaker and supporting tools: Alignments and analysis of multiple genomic DNA sequences.

Analysis of multiple sequence alignments can generate important, testable hypotheses about the phylogenetic history and cellular function of genomic sequences. We describe the MultiPipMaker server, which aligns multiple, long genomic DNA sequences quickly and with good sensitivity (available at http://bio.cse.psu.edu/ since May 2001). Alignments are computed between a contiguous reference sequence and one or more secondary sequences, which can be finished or draft sequence. The outputs include a stacked set of percent identity plots, called a MultiPip, comparing the reference sequence with subsequent sequences, and a nucleotide-level multiple alignment. New tools are provided to search MultiPipMaker output for conserved matches to a user-specified pattern and for conserved matches to position weight matrices that describe transcription factor binding sites (singly and in clusters). We illustrate the use of MultiPipMaker to identify candidate regulatory regions in WNT2 and then demonstrate by transfection assays that they are functional. Analysis of the alignments also confirms the phylogenetic inference that horses are more closely related to cats than to cows.

Algorithms↗
PubMed2004

Correlation of Wnt-2 expression and beta-catenin intracellular accumulation in Chinese gastric cancers: relevance with tumour dissemination.

Wnt/beta-catenin signalling pathway is integrally associated with human tumour development and progression. Aberrant beta-catenin intracellular distribution has been found in gastric cancer, but the pattern of Wnt expression in stepwise gastrocarcinogenesis and its potential influence in beta-catenin distribution are still lesser known. By the methods of frozen tissue array-based immunohistochemistry, Western blot analysis and RT-PCR, a paralleled study was conducted to check Wnt2 expression and beta-catenin intracellular distribution in two major subtypes of gastric cancers (intestinal gastric cancer, i-GC and diffuse gastric cancer, d-GC) and their premalignant (intestinal metaplasia, IM and chronic gastritis, CG) and noncancerous counterparts. According to the results obtained and the clinical data collected, correlation of Wnt2 expression with beta-catenin translocalisation and their links with tumour dissemination were elucidated. The results demonstrated (1) that Wnt2 expression and cytoplasmic/nuclear beta-catenin accumulations appeared in most gastric cancers irrespective to their morphological phenotypes, (2) that over-expressed Wnt and nuclear translocalisation of beta-catenin were found in 68 and 58% of i-GCs and in 47 and 47% of d-GCs in a closely related pattern (P<0.01) and (3) that co-existence of Wnt2 up-regulation/beta-catenin nuclear translocalisation were positively associated with lymph node metastasis (P<0.05) as well as T-stage. These data indicate that Wnt/beta-catenin signalling pathway is activated in most of gastric cancers, which may play pivotal roles either in gastric cancer formation or in tumour invasion and dissemination.

Blotting, Western↗
PubMed2005

Identification and characterization of DISP3 gene in silico.

Lipid-modified soluble proteins Hedgehog (SHH, DHH and IHH) and WNT (WNT1, WNT2, WNT2B, WNT3, etc.) share distantly related mechanisms for ligand modification as well as for signaling through seven-transmembrane protein with Frizzled domain. Hedgehog and WNT signaling pathways network together during embryogenesis and carcinogenesis. Dispatched 1 (DISP1) and Dispatched 2 (DISP2) are human homologs for Drosophila Dispatched implicated in the release of lipid-anchored Hedgehog from producing cells. Here, we identified and characterized Dispatched 3 (DISP3) gene by using bioinformatics. DISP3 complete coding sequence was determined by assembling BU170953 EST and KIAA1337 uncharacterized cDNA. DISP3 gene at human chromosome 1p36.22 was linked to D1S2667 microsatellite maker and TERE1 gene, whose locus is associated with prostate cancer, bladder cancer, and liver cancer. DISP3 mRNA was expressed in human embryonic stem (ES) cells, brain, testis, lung carcinoid, neuroblastoma, retinoblastoma and brain tumor. DISPH1 domain with five transmembrane regions (codon 452-637 of DISP3) and DISPH2 domain with four transmembrane regions (codon 1116-1319 of DISP3) were identified as novel domains conserved between DISP3 (1392 aa) and DISP1. The region around DISPH1 and DISPH2 domains of DISP3 protein was the Patched homologous region conserved among Patched family members and DISP family members. Because DISP3 and DISP1 are multi-span transmembrane proteins with the Patched homologous region, DISP3 is predicted to be implicated in the release of lipid-anchored secreted proteins. This is the first report on identification and characterization of the DISP3 gene.

Amino Acid Sequence↗
PubMed2005

Molecular evolution of Wnt2b orthologs.

WNT family proteins transduce signals through Frizzled (FZD) receptors with extracellular WNT-binding domain and cytoplasmic Dishevelled-binding domain. WNT2B-ST7L and WNT2-ST7 loci are paralogous regions within the human genome. WNT2B isoform 2 and WNT2 are canonical WNTs to activate the beta-catenin - TCF pathway in human cancer, especially in gastric cancer. Here, the rat Wnt2b gene was identified and characterized by using bioinformatics. The rat Wnt2b gene, consisting of five exons, was located within AC106372.5 genome sequence. Wnt2b core promoter region (nucleotide position 234449-233652 of AC106372.5 rat genome sequence) was identified as an evolutionarily conserved region. GC content of rat Wnt2b promoter was 71.8%. Nucleotide identity between human and rat Wnt2b promoters was 71.2%. E box, CP2-binding site, CCAAT box and ZNFN1A1 (IKAROS)-binding site were located within the conserved region of rat Wnt2b, mouse Wnt2b, and human WNT2B promoters. Rat Wnt2b (391 aa), human WNT2B isoform 2 and other vertebrate Wnt2b orthologs were type II transmembrane proteins with cleavable extracellular WNT domain, while vertebrate Wnt2 orthologs were secreted proteins. Twenty-four Cys residues were conserved among vertebrate Wnt2b and Wnt2 orthologs. Glycosylation sites at Asn 283 of rat Wnt2b and RGD motif were identified within mammalian Wnt2b orthologs, but not within vertebrate Wnt2 orthologs and zebrafish wnt2b. Zebrafish wnt2b acquired N-terminal cytoplasmic region to evolve into type II transmembrane protein, and then mammalian Wnt2b orthologs acquired integrin-targeting RGD motif within the extracellular WNT domain. This is the first report on the rat Wnt2b gene as well as on molecular evolution of the Wnt2b orthologs.

Amino Acid Sequence↗
PubMed2001

Induced repatterning of type XVIII collagen expression in ureter bud from kidney to lung type: association with sonic hedgehog and ectopic surfactant protein C.

Epithelial-mesenchymal tissue interactions regulate the formation of signaling centers that play a role in the coordination of organogenesis, but it is not clear how their activity leads to differences in organogenesis. We report that type XVIII collagen, which contains both a frizzled and an endostatin domain, is expressed throughout the respective epithelial bud at the initiation of lung and kidney organogenesis. It becomes localized to the epithelial tips in the lung during the early stages of epithelial branching, while its expression in the kidney is confined to the epithelial stalk region and is lost from the nearly formed ureter tips, thus displaying the reverse pattern to that in the lung. In recombinants, between ureter bud and lung mesenchyme, type XVIII collagen expression pattern in the ureter bud shifts from the kidney to the lung type, accompanied by a shift in sonic hedgehog expression in the epithelium. The lung mesenchyme is also sufficient to induce ectopic lung surfactant protein C expression in the ureter bud. Moreover, the shift in type XVIII collagen expression is associated with changes in ureter development, thus resembling aspects of early lung type epigenesis in the recombinants. Respecification of collagen is necessary for the repatterning process, as type XVIII collagen antibody blocking had no effect on ureter development in the intact kidney, whereas it reduced the number of epithelial tips in the lung and completely blocked ureter development with lung mesenchyme. Type XVIII collagen antibody blocking also led to a notable reduction in the expression of Wnt2, which is expressed in the lung mesenchyme but not in that of the kidney, suggesting a regulatory interaction between this collagen and Wnt2. Respecification also occurred in a chimeric organ containing the ureter bud and both kidney and lung mesenchymes, indicating that the epithelial tips can integrate the morphogenetic signals independently. A glial cell line-derived neurotrophic factor signal induces loss of type XVIII collagen from the ureter tips and renders the ureter bud competent for repatterning by lung mesenchyme-derived signals. Our data suggest that differential organ morphogenesis is regulated by an intra-organ patterning process that involves coordination between inductive signals and matrix molecules, such as type XVIII collagen.

Animals↗
PubMed2005

Wnt2 as a new therapeutic target in malignant pleural mesothelioma.

Malignant mesothelioma of the pleura (MPM) is a highly aggressive neoplasm with a poor prognosis and limited treatment options. A better understanding of its pathogenesis is essential to developing alternative therapeutic strategies. We previously demonstrated that the Wnt signaling pathway is activated in MPM through the overexpression of disheveled proteins. To extend our knowledge of Wnt signaling activation in MPM, we performed Wnt-specific microarrays in normal pleura and MPM. We found that the most common event in MPM was the upregulation of Wnt2. We inhibited Wnt2 by siRNA and a monoclonal anti-Wnt2 antibody and analyzed their effects on apoptosis and downstream signaling effectors. We then assessed the antiproliferative effects of the Wnt2 antibody and Alimta, one of the current standard treatments of MPM. We confirmed Wnt2 overexpression at the mRNA and protein level in MPM cell lines and tissues. We then demonstrated that inhibition of Wnt2 by siRNA or a monoclonal antibody induces programmed cell death in MPM cells. We next analyzed the effects of the anti-Wnt2 antibody and of Alimta on MPM cell proliferation. We found that although Wnt2 antibody by itself had less antiproliferative potency than Alimta, the two in combination had substantially more activity than Alimta alone. We thus propose that inhibition of Wnt2 is of therapeutic interest in the development of more effective treatments for MPM.

Antibodies, Monoclonal↗
PubMed2002

Identification of Gasz, an evolutionarily conserved gene expressed exclusively in germ cells and encoding a protein with four ankyrin repeats, a sterile-alpha motif, and a basic leucine zipper.

To discover causes of infertility and potential contraceptive targets, we used in silico subtraction and genomic database mining to identify conserved genes with germ cell-specific expression. In silico subtraction identified an expressed sequence tag (EST) present exclusively in a newborn mouse ovary library. The full-length cDNA sequence corresponding to this EST encodes a novel protein containing four ankyrin (ANK) repeats, a sterile-alpha motif (SAM), and a putative basic leucine zipper (bZIP) domain. Northern blot and semiquantitative RT-PCR analyses demonstrated that the mRNA is exclusively expressed in the mouse testis and ovary. The expression sites were localized by in situ hybridization to pachytene spermatocytes in the testis and oocytes in the ovary. Immunohistochemistry showed that the novel protein is localized to the cytoplasm in pachytene spermatocytes and early spermatids, oocytes at all stages of oogenesis, and in early preimplantation embryos. Based on its germ cell-specific expression and the presence of ANK, SAM, and basic leucine zipper domains, we have termed this novel protein GASZ. The mouse Gasz gene, which consists of 13 exons and spans 60 kb, is located on chromosome 6 between the Wnt2 and cystic fibrosis transmembrane conductance regulator (Cftr) genes. Using genomic database mining, orthologous genes encoding GASZ were identified in the rat, cow, baboon, chimpanzee, and human. Phylogenetic analyses reveal that the GASZ proteins are highly conserved among these species. Human and mouse GASZ proteins share 85.3% amino acid identity, and human and chimpanzee GASZ proteins differ by only 3 out of 475 amino acids. In humans, the GASZ gene resides on chromosome 7 and is similarly composed of 13 exons. Because both ANK repeats and the SAM domain function as protein-protein interaction modules that mediate signal transduction cascades in some systems, GASZ may represent an important cytoplasmic signal transducer that mediates protein-protein interactions during germ cell maturation in both males and females and during preimplantation embryogenesis.

Adaptor Proteins, Signal Transducing↗
PubMed2006

Expression patterns of Wnt genes during development of an anterior part of the chicken eye.

To address the roles of Wnts in the development of the anterior eye, we used a chicken model to perform comprehensive expression analysis of all Wnt genes during anterior eye development. In analyzing the available genomic sequences, we found that the chicken genome encodes 18 Wnt proteins that are homologous to corresponding human and mouse proteins. The mRNA sequences for 12 chicken Wnt genes are available in GenBank, and mRNAs for six other Wnt genes (Wnt2, Wnt5b, Wnt7b, Wnt8b, Wnt9b, and Wnt16) were identified and cloned based on the homology to the genes from other species. In addition, we found that chicken Wnt3a and Wnt7b genes encode two alternative mRNA isoforms containing different first exons. Following in situ hybridization, we found that out of 18 Wnt genes, 11 genes were expressed in the anterior eye, exhibiting distinct temporal-spatial patterns. Several Wnts were expressed in the lens, including Wnt2 and Wnt2b in the anterior epithelium and Wnt5a, Wnt5b, Wnt7a, and Wnt7b in the differentiating lens fiber cells. In the cornea, we detected Wnt3a, Wnt6, and Wnt9b in the ocular surface ectoderm, including the corneal epithelium, and Wnt9a in the corneal endothelium from the onset of its differentiation. In the optic cup, Wnt2, Wnt2b, and Wnt9a were localized in the rim of the optic cup (presumptive iris), while Wnt5a and Wnt16 were detected in the ciliary epithelium/iris zone of the differentiated optic cup, and Wnt6 was expressed in the iridial mesenchyme. These data suggest that Wnt signaling might play important roles in anterior eye development.

Animals↗
PubMed2004

Identification and characterization of evolutionarily conserved pufferfish, zebrafish, and frog orthologs of GASZ.

We previously identified Gasz (a germ cell-specific gene encoding a protein containing four ankyrin repeats, a sterile-alpha motif, and a basic leucine zipper) in six mammalian species. Here, we report GASZ orthologs in pufferfish (Fugu rubripes), zebrafish (Danio verio), and frog (Xenopus laevis). Sequences of the three Gasz cDNAs were determined by database mining and 5'- and 3'-rapid amplification of cDNA ends (RACE) followed by sequencing. The three orthologous vertebrate genes encode proteins structurally similar to mammalian GASZ and contain the characteristic four ankyrin repeats (ANKs) and sterile-alpha motif (SAM). Their ANK and SAM domains share 55- 74% and 38-55% amino acid identity with those in human GASZ, respectively. Similar to human and mouse Gasz genes, pufferfish Gasz is composed of 13 exons, spanning approximately 12 kilobases, and flanked by Cftr at its 5'-end and Wnt2 at its 3'-end. Northern and Western blot analyses detect frog Gasz expression only in testis and ovary. In situ hybridization and immunohistochemical analyses show that frog Gasz mRNA and protein expression is confined to pachytene spermatocytes in the testis and to oocytes in the ovary. In frog oocytes, GASZ protein appears to localize to a cytoplasmic structure resembling the Balbiani body, a postulated mRNA transport organizer in the cytoplasm. The high evolutionary conservation and germ cell specificity suggest that GASZ plays an essential role in gametogenesis. The data presented here are important for future studies of the physiological roles of GASZ using fish and amphibians as animal models.

Adaptor Proteins, Signal Transducing↗