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Wei-Qiang Gao

Publications and source records attributed to Wei-Qiang Gao.

16 recordsLinked to original sources
PubMed2025

ATOH8 confers the vulnerability of tumor cells to ferroptosis by repressing SCD expression.

Emerging evidence indicates that transcriptional regulation plays pivotal roles in modulating cellular vulnerability to ferroptosis. However, the intricate mechanisms governing these processes remain poorly understood. In this study, we identify ATOH8, a basic helix-loop-helix (bHLH) transcription factor, as a key player in ferroptosis regulation. ATOH8 is significantly upregulated in tumor cells following treatment with a ferroptosis inducer. Overexpression of ATOH8 increases the susceptibility of tumor cells to ferroptosis, while deletion of ATOH8 promotes ferroptosis evasion. Mechanistically, ATOH8 confers the sensitivity of tumor cells to ferroptosis by suppressing the transcription of stearoyl-CoA desaturase (SCD). Additionally, another bHLH family member, TCF3, is found to functions as a co-factor with ATOH8 by forming a TCF3-ATOH8 transcriptional repressive complex that suppresses SCD transcription. Furthermore, searching for upstream element reveals that EZH2 epigenetically suppresses ATOH8 expression by promoting DNA methylation in the ATOH8 promoter region and increasing the level of H3K27 me3. Importantly, pharmacological inhibition of EZH2 in a combined with a ferroptosis inducer markedly impedes tumor growth both in vitro and in vivo. Collectively, our study elucidates a molecular link between ferroptosis and epigenetic and transcriptional regulation, highlighting the potential of EZH2 and ATOH8 as therapeutic targets for cancer treatment.

Ferroptosis↗
PubMed2006

HATH1 expression in mucinous cancers of the colorectum and related lesions.

PURPOSE: Mucinous cancers and signet ring carcinomas are distinct classes of colon cancers characterized by their production of copious quantities of intestinal goblet cell mucin, MUC2. Deletion of transcription factor HATH1 ablates the biogenesis of goblet cells in developing mouse intestine, and forced expression of HATH1 results in elevated expression of MUC2 in colon cancer cells. The aim of this study was to assess the possible role of HATH1 in the development of mucinous cancers and signet ring carcinomas. EXPERIMENTAL DESIGN: Immunohistochemistry and confocal microscopy was used to examine HATH1 expression and subcellular distribution in normal colon and small intestine, mucinous cancers, signet ring carcinomas, and nonmucinous cancers and in precursor lesions, including hyperplastic polyps, serrated adenomas, tubular adenomas, and villous adenomas. We also analyzed the transactivation of MUC2 promoter/reporter constructs by a HATH1 expression vector. RESULTS: HATH1 expression transactivated MUC2 promoter/reporter constructs, an activity that was significantly inhibited by mutation of putative HATH1-binding sites. HATH1 was expressed in the nuclei of goblet cells and in the cytoplasm and nuclei of enteroendocrine cells of the colon. In the small intestine, only cytoplasmic expression of HATH1 in enteroendocrine cells was detected. HATH1 was found to be strongly expressed in the nuclei of hyperplastic polyps, serrated adenomas, villous adenomas, mucinous cancers, and signet ring carcinomas but repressed in nonmucinous cancers and tubular adenomas. CONCLUSIONS: This study confirms the importance of HATH1 for the development of intestinal secretory cells. The results further suggest that HATH1 is an important factor in the up-regulation of MUC2 expression that occurs in mucinous cancers and signet ring carcinomas. In addition, the expression of HATH1 in hyperplastic polyps, serrated adenomas, and villous adenomas lends support to the hypothesis that these neoplasms are frequent precursors in mucinous cancer and signet ring carcinoma development.

Adenocarcinoma, Mucinous↗
PubMed2006

Basic helix-loop-helix gene Hes6 delineates the sensory hair cell lineage in the inner ear.

The basic helix-loop-helix (bHLH) gene Hes6 is known to promote neural differentiation in vitro. Here, we report the expression and functional studies of Hes6 in the inner ear. The expression of Hes6 appears to be parallel to that of Math1 (also known as Atoh1), a bHLH gene necessary and sufficient for hair cell differentiation. Hes6 is expressed initially in the presumptive hair cell precursors in the cochlea. Subsequently, the expression of Hes6 is restricted to morphologically differentiated hair cells. Similarly, the expression of Hes6 in the vestibule is in the hair cell lineage. Hes6 is dispensable for hair cell differentiation, and its expression in inner ear hair cells is abolished in the Math1-null animals. Furthermore, the introduction of Hes6 into the cochlea in vitro is not sufficient to promote sensory or neuronal differentiation. Therefore, Hes6 is downstream of Math1 and its expression in the inner ear delineates the sensory lineage. However, the role of Hes6 in the inner ear remains elusive.

Animals↗
PubMed2005

Notch signaling is required for normal prostatic epithelial cell proliferation and differentiation.

Notch pathway is crucial for stem/progenitor cell maintenance, growth and differentiation in a variety of tissues. Using a transgenic cell ablation approach, we found in our previous study that cells expressing Notch1 are crucial for prostate early development and re-growth. Here, we further define the role of Notch signaling in regulating prostatic epithelial cell growth and differentiation using biochemical and genetic approaches in ex vivo or in vivo systems. Treatment of developing prostate grown in culture with inhibitors of gamma-secretase/presenilin, which is required for Notch cleavage and activation, caused a robust increase in proliferation of epithelial cells co-expressing cytokeratin 8 and 14, lack of luminal/basal layer segregation and dramatically reduced branching morphogenesis. Using conditional Notch1 gene deletion mouse models, we found that inactivation of Notch1 signaling resulted in profound prostatic alterations, including increased tufting, bridging and enhanced epithelial proliferation. Cells within these lesions co-expressed both luminal and basal cell markers, a feature of prostatic epithelial cells in predifferentiation developmental stages. Microarray analysis revealed that the gene expression in a number of genetic networks was altered following Notch1 gene deletion in prostate. Furthermore, expression of Notch1 and its effector Hey-1 gene in human prostate adenocarcinomas were found significantly down-regulated compared to normal control tissues. Taken together, these data suggest that Notch signaling is critical for normal cell proliferation and differentiation in the prostate, and deregulation of this pathway may facilitate prostatic tumorigenesis.

Amyloid Precursor Protein Secretases↗
PubMed2005

Novel method of generating prostate-specific Cre-LoxP gene switching via intraductal delivery of adenovirus.

BACKGROUND: In order to facilitate elucidation of oncogene or tumor suppressor gene function on initiation and progression of prostate cancer, it would be advantageous to develop an effective method to generate spatially and temporally controlled gene modification in murine prostates. METHODS: Adenovirus expressing Cre-recombinase (Adeno-Cre) was intraductally injected into the prostate of ROSA26 reporter mice. Immmunohistochemical and X-gal staining were performed on prostate tissue sections harvested from mice at various time points following viral injection to confirm expression and activity of Cre-recombinase, respectively. RESULTS: Adenovirus was intraductally delivered to the anterior lobe of the mouse prostate. Using this method of intraductal injection, we were able to precisely obtain Adeno-Cre infection to a majority of epithelial cells but not in the stromal cells or other organs. We further demonstrated that Adeno-Cre infected epithelial cells not only expressed Cre-recombinase enzyme but more importantly, Cre-recombinase activity was revealed through positive X-gal staining in Rosa26 reporter mice, thus, confirming epithelial-specific Cre-loxP recombination in Adeno-Cre infected prostate tissue sections. CONCLUSIONS: This novel method of direct genetic delivery into adult murine prostates could provide an alternative to the more expensive and time-consuming transgenic/knockout approaches. The latter also have other limitations such as the availability of cell-type specific or temporally-regulated promoters, and the complication of genetic background differences, which can potentially be complemented by the technology we describe here.

Adenoviridae↗
PubMed2005

Isolation and culture of hair cell progenitors from postnatal rat cochleae.

Cochlear hair cells are a terminally differentiated cell population that is crucial for hearing. Although recent work suggests that there are hair cell progenitors in postnatal mammalian cochleae, isolation and culture of pure hair cell progenitors from a well-defined cochlear area have not been reported. Here we present an experimental method that allows isolation and culture of hair cell progenitors from postnatal rat cochleae. These progenitor cells are isolated from the lesser epithelial ridge (LER, or outer spiral sulcus cell) area of pre-plated neonatal rat cochlear segments. They express the same markers as LER cells in vivo, including ZO1, Islet1, Hes1, and Hes5. When these cells are induced to express Hath1, they show the potential to differentiate into hair cell-like cells. Interestingly, these cells can be lifted from monolayer cultures and maintained in aggregate cultures in which spheres can be formed. Hair cell progenitors in the spheres display their proliferating capability and express only epithelial markers. Furthermore, when these spheres are mixed with dissociated mesenchymal cells prepared from postnatal rat utricular whole mounts, and replated onto a collagen substratum, the epithelial progenitor cells are able to differentiate into cells expressing markers of hair cells and supporting cells in epithelial islands, which mirrors the inner ear sensory epithelium in vivo. Successful isolation and culture of hair cell progenitors from the mammalian cochlea will facilitate studies on gene expression profiling and mechanism of differentiation/regeneration of hair cells, which are crucial for repairing hearing loss.

Actins↗
PubMed2005

A role for Hath1, a bHLH transcription factor, in colon adenocarcinoma.

A significant reduction or loss of goblet cells is often observed in clinical samples of colon adenocarcinomas, which is the predominant form of colon carcinoma. Mice lacking Math1, a bHLH transcription factor downstream of the Notch signaling pathway, demonstrates that Math1 is necessary for cell fate determination of the intestinal secretory cells, including goblet cells. Examination of Hath1, the human orthologue of Math1, expression in multiple colon tumor samples and colon cancer cell lines reveals a dramatic decrease in Hath1 expression in colon tumor samples and colon cancer cell lines. Hath1 expression in the HT29 colon cancer cell line can significantly inhibit its proliferation and anchorage-independent growth both in vitro and in vivo. At the molecular level, Hath1 may regulate the expression of MUC2, a mucin secreted by goblet cells, and Hath1 may also be a novel factor normally repressed as a consequence of activation of the Wnt signaling pathway, which has been clearly implicated in colon tumorigenesis.

Adenocarcinoma↗
PubMed2005

[Expression of the metalloproteinase domain of von Willebrand factor-cleaving protease and preparation of its McAb].

The von Willebrand factor-cleaving protease (vWF-cp) is a newly identified plasma metalloproteinase and plays an important role in the pathogenesis of thrombotic microangiopathy. In the present study, the metalloproteinase domain of vWF-cp was expressed by IPTG-induced the recombinant engineered E.coli strain harbouring pET28a (+)-vWF-cp/MD and purified using chromatography on Ni-NTA column. Then the BALB/c mice were immunized with the recombinant protein to prepare the monoclonal antibodies (McAb) against vWF-cp and the obtained McAbs were characterized. Furthermore, the expression panels of vWF-cp in human normal tissues were investigated using immunohistochemistry. The results showed that high-level expression of the recombinant protein was achieved, which existed as inclusion body and amounted to 28% of total bacteria protein. Three monoclonal antibodies against the metalloproteinase domain of vWF-cp were obtained and two of them, SZ-112 and SZ-113, were further evaluated. Both of them belong to IgG(1). The concentration of them in ascites was 4 mg/ml, and their titers were as high as 1 x 10(-5). The data of ELISA showed that SZ-112 and SZ-113 recognized different epitopes of recombinant protein. The Western blot and immunoprecipitation data showed that the two monoclonal antibodies reacted not only with the recombinant protein, but also with a 200 kD protein in platelet lysate. Moreover, the vWF-cp was found to be present in the cytoplasm of many human tissues such as liver, prostate, ovary, etc. However, the protease could not be detected in brain tissue. In conclusion, the above-mentioned research work contributed not only to the further study of the structure and function of this protease, but also to the establishment of the method for quantifying the vWF-cp antigen in plasma.

ADAM Proteins↗
PubMed2005

[A2 domain of human von Willebrand factor expressed in E. coli and its biological activity].

Von Willebrand factor (vWF) is the unique substrate for the metalloprotease, ADAMTS-13, and plays a pivotal role in the pathology of von Willebrand disease (vWD) and thrombotic thrombocytopenic purpure (TTP). To study the pathogenesis of TTP and to establish a method to diagnose TTP, the DNA fragment of vWF-A2 domain was amplified and inserted into expression vector with 6 x His tag (pQE-30), the recombinant expression vector was transformed into E. coli (strain M15) and induced by IPTG. The recombinant fragment comprising residues 718-905 of mature vWF was designated as rvWF-A2. It was purified by Ni-NTA resin column chromatography and refolded in Tris buffer containing GSH and GSSG. The results demonstrated that rvWF-A2 was expressed successfully in E. coli M15, amounting to 42% of total bacterial protein with the purity over 98%. It was identified that rvWF-A2 can be efficiently cleaved by the citrated normal plasma while no cleavage can be detected by the TTP plasma or plasma with EDTA. It is concluded that rvWF-A2 expressed efficiently in E. coli demonstrated excellent biological activity, which lays a solid foundation for establishment of method to measure quantatively the activity of ADAMTS-13.

ADAM Proteins↗
PubMed2004

Hath1, down-regulated in colon adenocarcinomas, inhibits proliferation and tumorigenesis of colon cancer cells.

A striking feature of colon tumors is the significant reduction of goblet cells. Although targeted deletion of Math1 in mice leads to a loss of intestinal secretory cells, including goblet cells, the role of Hath1 in colon tumorigenesis remains unknown. Here we report that Hath1, the human ortholog of Math1, was dramatically down-regulated in colon tumor samples and colon cancer cell lines. Overexpression of Hath1 in HT29, an aggressive colon cancer cell line, resulted in a significant inhibition on cell proliferation, anchorage-independent growth in soft agar and, more importantly, growth of human colon cancer cell xenografts in athymic nude mice. Such inhibition was accompanied by altered expression of a goblet cell differentiation marker, MUC2, and cell cycle regulators cyclin D1 and p27kip1. Hath1 expression also was up-regulated on inhibition of the Wnt pathway, which has been well implicated in colon tumorigenesis. Hence, this study suggests that Hath1 may be a novel factor downstream of the Wnt pathway capable of suppressing anchorage-independent growth of colon cancer cell lines. More importantly, this study is the first to establish a link between down-regulation of Hath1 expression and colon tumorigenesis.

Adenocarcinoma↗
PubMed2004

Notch1-expressing cells are indispensable for prostatic branching morphogenesis during development and re-growth following castration and androgen replacement.

Notch expression is frequently associated with progenitor cells, and its function is crucial for development. Our recent work showing that Notch1 is selectively expressed in basal epithelial cells of the prostate and higher Notch1 expression during development suggests that Notch1-expressing cells may define progenitor cells in the prostate. To test this hypothesis, we have generated a transgenic mouse line in which the Notch1-expressing cells can be ablated in a controlled manner. Specific targeting was achieved by expressing the bacterial nitroreductase, an enzyme that catalyzes its substrate into a cytotoxin capable of inducing apoptosis, under the Notch1 promoter. Cell death in transgenic prostate was confirmed by histological analyses including terminal dUTP nick-end labeling and caspase 3 immunocytochemical staining. We evaluated the consequences of ablation of Notch1-expressing cells in two systems, organ culture of early postnatal prostates and re-growth of prostate in castrated mice triggered by hormone replacement. Our data show that elimination of Notch1-expressing cells inhibited the branching morphogenesis, growth, and differentiation of early postnatal prostate in culture and impaired prostate re-growth triggered by hormone replacement in castrated mice. Furthermore, we found that Notch1 expression following castration and hormone replacement was concomitant with known basal cell markers p63 and cytokeratin 14 and was high in the proliferative human prostate epithelial cells. Taken together, these data suggest that Notch1-expressing cells define the progenitor cells in the prostatic epithelial cell lineage, which are indispensable for prostatic development and re-growth.

Androgens↗
PubMed2004

[Study of C1423T polymorphism of the von Willebrand factor-cleaving protease gene in Chinese Han population].

OBJECTIVE: The C1423T polymorphism in von Willebrand factor-cleaving protease (vWF-cp) gene affects its enzyme activity. The present study was to investigate the polymorphism frequency among Chinese Han population and its relevance to arterial thrombotic disorders. METHODS: An amplified 366 bp fragment of human vWF-cp gene was analyzed by Rsa I restriction assay in 400 unrelated individuals including 150 with acute ischemic stroke (AIS), 103 with acute myocardial infarction (AMI) and 147 age- and gender-matched healthy controls. The resulting products were analyzed by 12% polyacrylamide gels electrophoresis and stained with ethidium bromide. RESULTS: Twelve cases were C1423T heterozygous, the C1423T frequencies were 98.5% and 1.5%, and the heterozygosity and allele frequency were 3% and 1.5%, respectively, which were remarkably lower than those reported in Japanese population. No 1423T/T homozygote was found. Besides, there was no significant difference between healthy controls and patients with thrombotic disorders. CONCLUSION: C1423T polymorphism is low frequency in both controls and patients of Han population.

Adult↗
PubMed2004

[Residual collagen binding assay for von Willebrand factor-cleaving protease activity and its clinical application].

von Willebrand factor-cleaving protease (vWF-cp) is a newly identified metalloproteinase. The activity of vWF-cp would vary in different physiological or pathological states. To explore activity detectron of von Willebrand factor-cleaving protease and its clinical application, the vWF-cp activity was measured by a sensitive enzyme-linked immunoadsorbent assay to detect the residual collagen binding activity (R-CBA) of von Willebrand factor before and after digestion with vWF-cp. Moreover, its activity deficiency in patients with thrombotic thrombocytopenic purpura (TTP) and solid tumors was also investigated. The results showed that the residual collagen binding assay was sensitive enough to measure the serum or plasma vWF-cp activity in 87 health individuals, 79 patients suffering from TTP and solid tumors. The coefficient of variation within and between the batches was were 3.60% and 8.35%, respectively. The serum and plasma vWF-cp activity in health individuals was (79.47 +/- 10.78)% (n = 53) and (78.79 +/- 9.17)% (n = 30), respectively, whereas the vWF-cp activity in patients with TTP, benign and malignant tumors was significantly decreased (P values were less than 0.001, 0.03 and 0.001, respectively). It is concluded that the vWF-cp activity in plasma or serum of patients with TTP and solid tumors markedly decrease, especially in patients with TTP. Assay of the vWF-cp activity using R-CBA is a simple method.

ADAM Proteins↗
PubMed2003

Inhibition of epithelial ductal branching in the prostate by sonic hedgehog is indirectly mediated by stromal cells.

Sonic hedgehog (Shh), a vertebrate homologue of the Drosophila segment-polarity gene hedgehog, has been reported to play an important role during normal development of various tissues. Abnormal activities of Shh signaling pathway have been implicated in tumorigenesis such as basal cell carcinomas and medulloblastomas. Here we show that Shh signaling negatively regulates prostatic epithelial ductal morphogenesis. In organotypic cultures of developing rat prostates, Shh inhibited cell proliferation and promoted differentiation of luminal epithelial cells. The expression pattern of Shh and its receptors suggests a paracrine mechanism of action. The Shh receptors Ptc1 (Patched1) and Ptc2 were found to be expressed in prostatic stromal cells adjacent to the epithelium, where Shh itself was produced. This paracrine model was confirmed by co-culturing the developing prostate in the presence of stromal cells transfected with a vector expressing a constitutively active form of Smoothened, the real effector of the Shh signaling pathway. Furthermore, expression of activin A and TGF-beta1 that were shown previously to inhibit prostatic epithelial branching was up-regulated following Shh treatment in the organotypic cultures. Taken together, these results suggest that Shh negatively regulates prostatic ductal branching indirectly by acting on the surrounding stromal cells, at least partly via up-regulating expression of activin A and TGF-beta1.

Activins↗
PubMed2002

Expression profiling of a human cell line model of prostatic cancer reveals a direct involvement of interferon signaling in prostate tumor progression.

Cancer-associated fibroblasts induce malignant behavior in genetically initiated but nontumorigenic human prostatic epithelium. The genetic basis for such transformation is still unknown. By using Affymetrix GeneChip technology, we profiled genomewide gene expression of transformed [tumorigenic benign prostatic hyperplasia (BPH1)(CAFTD)] and parental (nontumorigenic BPH1) cells. We identified differentially expressed genes, which are associated with tumorigenesis or tumor progression. One striking finding is that a significant portion of the down-regulated genes belongs to interferon (IFN)-inducible molecules. We show that IFN inhibited the tumorigenic BPH1(CAFTD) cell proliferation and colony formation in vitro and inhibited tumor growth in xenografts in vivo. Expression of the IFN-inducible molecules correlates with the growth-inhibiting effects of IFN. In addition, these genes are reported to be mapped mainly to two chromosomal regions, 10q23-26 and 17q21, which are frequently deleted in human prostate cancers. Furthermore, in silico data-mining with the GeneLogic database revealed that expression of the IFN-inducible genes was down-regulated in approximately 30% of the 49 clinically characterized samples of prostatic adenocarcinomas. Collectively, we show that there seems to be a direct link between IFN-inducible molecules and prostatic tumor progression. These findings suggest IFN-inducible molecules as potential therapeutic targets for the treatment of prostate cancer.

Cell Division↗