scholarly journals Heme Oxygenase-1 Suppresses Wnt Signaling Pathway in Nonalcoholic Steatohepatitis-Related Liver Fibrosis

2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Jinghua Du ◽  
Weiguang Ren ◽  
Qingshan Zhang ◽  
Na Fu ◽  
Fang Han ◽  
...  

Background and Aim. Heme oxygenase-1 (HO-1) has been verified to play an important role in nonalcoholic steatohepatitis (NASH), but the mechanism remains unclear. In this study, we aimed to clarify whether induction of HO-1 reverses steatofibrosis via suppression of the Wnt signaling pathway and to explore the potential mechanism of HO-1 on NASH-related liver fibrosis. Methods. Mice were fed with a methionine-choline-deficient (MCD) diet for 8 weeks to induce steatohepatitis-related liver fibrosis and were treated with HO-1 inducer Hemin and inhibitor ZnPP. Mouse sera were collected for the biochemical analysis, and livers were obtained for further histological observation and gene expression analysis. HSC-T6 cells were cultured for the in vitro study and were administrated with Hemin and si-HO-1 to induce or inhibit the expression of HO-1. qPCR and Western blot were used to assess the mRNA and protein levels of genes. Results. MCD-fed mice developed marked macrovesicular steatosis, focal necrosis, and inflammatory infiltration and pericellular fibrosis in liver sections. Administration of Hemin could significantly ameliorate the severity of steatosis, inflammation, and fibrosis and also could decrease the serum ALT and AST. We demonstrated that HO-1 induction was able to downregulate the key regulator of the canonical Wnt pathway Wnt1 and the noncanonical Wnt pathway Wnt5a. The downstream factors of the Wnt pathway β-catenin and NFAT5 were inhibited by Hemin, but GSK-3β was upregulated compared to the MCD group, which were consistent with the in vitro study. Hemin markedly inhibited the TGF-β1/Smad signaling pathway in both in vivo and in vitro studies. Conclusion. Our study demonstrated that HO-1 inhibited the activation of canonical and noncanonical Wnt signaling pathways in NASH-related liver fibrosis. Thus, these results may suggest a new therapeutic strategy for NASH-related liver fibrosis.

2021 ◽  
Vol 20 ◽  
pp. 153303382110412
Author(s):  
Jiancong Hu ◽  
Zihan Wang ◽  
Junxiong Chen ◽  
Zhaoliang Yu ◽  
Jingdan Zhang ◽  
...  

Inhibitor of β-catenin and T-cell factor (ICAT) was first found as a polypeptide that blocks β-catenin–TCF interaction. Abundant evidence has shown that ICAT has different functions in diverse cancers’ progression. Nevertheless, the roles it plays in colorectal cancer (CRC) have not been described. Here, we documented that ICAT expression was higher in CRC tissue than in the adjacent normal tissue and that prognosis was better in high-ICAT expression patients. The overexpression of ICAT inhibited CRC cell proliferation both in vitro and in vivo. Wnt pathway transcriptional activity was suppressed in the CRC cells with ICAT overexpression, where the CCND1 and MYC expression, which occurs downstream of the Wnt signaling pathway, was inhibited. Co-immunoprecipitation experiments showed that ICAT bound with β-catenin in stable overexpression cell lines; immunofluorescence showed the co-localization of ICAT and β-catenin in the cytoplasm. Overall, our study reveals that ICAT inhibits CRC cell proliferation by binding to cytoplasm-located β-catenin, and prevents its translocation, which results in Wnt signaling pathway inactivation. It may provide a scientific foundation for focusing on ICAT in treatments for CRC.


2015 ◽  
Vol 13 (1) ◽  
pp. 720-730 ◽  
Author(s):  
LIPING OU ◽  
LIAOQIONG FANG ◽  
HEJING TANG ◽  
HAI QIAO ◽  
XIAOMEI ZHANG ◽  
...  

2019 ◽  
Vol 20 (21) ◽  
pp. 5391 ◽  
Author(s):  
Wörthmüller ◽  
Salicio ◽  
Oberson ◽  
Blum ◽  
Schwaller

Malignant mesothelioma (MM) is an aggressive asbestos-linked neoplasm, characterized by dysregulation of signaling pathways. Due to intrinsic or acquired chemoresistance, MM treatment options remain limited. Calretinin is a Ca2+-binding protein expressed during MM tumorigenesis that activates the FAK signaling pathway, promoting invasion and epithelial-to-mesenchymal transition. Constitutive calretinin downregulation decreases MM cells’ growth and survival, and impairs tumor formation in vivo. In order to evaluate early molecular events occurring during calretinin downregulation, we generated a tightly controlled IPTG-inducible expression system to modulate calretinin levels in vitro. Calretinin downregulation significantly reduced viability and proliferation of MM cells, attenuated FAK signaling and reduced the invasive phenotype of surviving cells. Importantly, surviving cells showed a higher resistance to cisplatin due to increased Wnt signaling. This resistance was abrogated by the Wnt signaling pathway inhibitor 3289-8625. In various MM cell lines and regardless of calretinin expression levels, blocking of FAK signaling activated the Wnt signaling pathway and vice versa. Thus, blocking both pathways had the strongest impact on MM cell proliferation and survival. Chemoresistance mechanisms in MM cells have resulted in a failure of single-agent therapies. Targeting of multiple components of key signaling pathways, including Wnt signaling, might be the future method-of-choice to treat MM.


2002 ◽  
Vol 22 (11) ◽  
pp. 3803-3819 ◽  
Author(s):  
Takayuki Kadoya ◽  
Hideki Yamamoto ◽  
Toshiaki Suzuki ◽  
Akira Yukita ◽  
Akimasa Fukui ◽  
...  

ABSTRACT Axam has been identified as a novel Axin-binding protein that inhibits the Wnt signaling pathway. We studied the molecular mechanism by which Axam stimulates the downregulation of β-catenin. The C-terminal region of Axam has an amino acid sequence similar to that of the catalytic region of SENP1, a SUMO-specific protease (desumoylation enzyme). Indeed, Axam exhibited activity to remove SUMO from sumoylated proteins in vitro and in intact cells. The Axin-binding domain is located in the central region of Axam, which is different from the catalytic domain. Neither the Axin-binding domain nor the catalytic domain alone was sufficient for the downregulation of β-catenin. An Axam fragment which contains both domains was able to decrease the level of β-catenin. On substitution of Ser for Cys547 in the catalytic domain, Axam lost its desumoylation activity. Further, this Axam mutant decreased the activity to downregulate β-catenin. Although Axam strongly inhibited axis formation and expression of siamois, a Wnt-response gene, in Xenopus embryos, AxamC547S showed weak activities. These results demonstrate that Axam functions as a desumoylation enzyme to downregulate β-catenin and suggest that sumoylation is involved in the regulation of the Wnt signaling pathway.


2001 ◽  
Vol 75 (6) ◽  
pp. 2857-2865 ◽  
Author(s):  
Michele Brunori ◽  
Maddalena Malerba ◽  
Haruhiko Kashiwazaki ◽  
Richard Iggo

ABSTRACT Despite important advances in understanding the molecular basis of cancer, few treatments have been devised which rationally target known causal oncogenic defects. Selectively replicating viruses have a major advantage over nonreplicating viruses to target these defects because the therapeutic effect of the injected virus is augmented by virus produced within the tumor. To permit rational targeting of colon tumors, we have developed replicating adenoviruses that express the viral E1B and E2 genes from promoters controlled by the Tcf4 transcription factor. Tcf4 is constitutively activated by mutations in the adenomatous polyposis coli and β-catenin genes in virtually all colon tumors and is constitutively repressed by Groucho and CtBP in normal tissue. The Tcf-E2 and Tcf-E1B promoters are active in many, but not all, cell lines with activation of the wnt pathway. Viruses with Tcf regulation of E2 expression replicate normally in SW480 colon cancer cells but show a 50- to 100-fold decrease in replication in H1299 lung cancer cells and WI38 normal fibroblasts. Activation of wnt signaling by transduction of a stable β-catenin mutant into normal fibroblasts renders the cells permissive for virus replication. Insertion of Tcf4 sites in the E1B promoter has only small effects on replication in vitro but significantly reduces the inflammatory response in a rodent lung model in vivo. Replicating adenoviruses with Tcf regulation of both E1B and E2 transcription are potentially useful for the treatment of liver metastases from colorectal tumors, but additional changes will be required to produce a virus that can be used to treat all colon tumors.


2002 ◽  
Vol 22 (4) ◽  
pp. 1172-1183 ◽  
Author(s):  
Eek-hoon Jho ◽  
Tong Zhang ◽  
Claire Domon ◽  
Choun-Ki Joo ◽  
Jean-Noel Freund ◽  
...  

ABSTRACT Axin2/Conductin/Axil and its ortholog Axin are negative regulators of the Wnt signaling pathway, which promote the phosphorylation and degradation of β-catenin. While Axin is expressed ubiquitously, Axin2 mRNA was seen in a restricted pattern during mouse embryogenesis and organogenesis. Because many sites of Axin2 expression overlapped with those of several Wnt genes, we tested whether Axin2 was induced by Wnt signaling. Endogenous Axin2 mRNA and protein expression could be rapidly induced by activation of the Wnt pathway, and Axin2 reporter constructs, containing a 5.6-kb DNA fragment including the promoter and first intron, were also induced. This genomic region contains eight Tcf/LEF consensus binding sites, five of which are located within longer, highly conserved noncoding sequences. The mutation or deletion of these Tcf/LEF sites greatly diminished induction by β-catenin, and mutation of the Tcf/LEF site T2 abolished protein binding in an electrophoretic mobility shift assay. These results strongly suggest that Axin2 is a direct target of the Wnt pathway, mediated through Tcf/LEF factors. The 5.6-kb genomic sequence was sufficient to direct the tissue-specific expression of d2EGFP in transgenic embryos, consistent with a role for the Tcf/LEF sites and surrounding conserved sequences in the in vivo expression pattern of Axin2. Our results suggest that Axin2 participates in a negative feedback loop, which could serve to limit the duration or intensity of a Wnt-initiated signal.


2017 ◽  
Vol 89 (4) ◽  
pp. 631-639 ◽  
Author(s):  
Meihong Shi ◽  
Jianyong Cheng ◽  
Yamei He ◽  
Zhongliang Jiang ◽  
Bello M. Bodinga ◽  
...  

2008 ◽  
Vol 295 (6) ◽  
pp. G1150-G1158 ◽  
Author(s):  
Sharon DeMorrow ◽  
Heather Francis ◽  
Eugenio Gaudio ◽  
Julie Venter ◽  
Antonio Franchitto ◽  
...  

Cholangiocarcinomas are cancers that have poor prognosis and limited treatment options. The noncanonical Wnt pathway is mediated predominantly by Wnt 5a, which activates a Ca2+-dependent pathway involving protein kinase C, or a Ca2+-independent pathway involving the orphan receptor Ror2 and subsequent activation of Jun NH2-terminal kinase (JNK). This pathway is associated with growth-suppressing effects in numerous cell types. We have shown that anandamide decreases cholangiocarcinoma growth in vitro. Therefore, we determined the effects of anandamide on cholangiocarcinoma tumor growth in vivo using a xenograft model and evaluated the effects of anandamide on the noncanonical Wnt signaling pathways. Chronic administration of anandamide decreased tumor growth and was associated with increased Wnt 5a expression in vitro and in vivo. Treatment of cholangiocarcinoma cells with recombinant Wnt 5a decreased cell proliferation in vitro. Neither anandamide nor Wnt 5a affected intracellular calcium release, but both increased the JNK phosphorylation. Stable knockdown of Wnt 5a or Ror2 expression in cholangiocarcinoma cells abolished the effects of anandamide on cell proliferation and JNK activation. Modulation of the endocannabinoid system may be important in cholangiocarcinoma treatment. The antiproliferative actions of the noncanonical Wnt signaling pathway warrants further investigation to dissect the mechanism by which this may occur.


2021 ◽  
Vol 7 ◽  
Author(s):  
Jing Xie ◽  
Li Huang ◽  
You-Guang Lu ◽  
Da-Li Zheng

Head and neck squamous cell carcinoma (HNSCC) is the most common type of head and neck tumor. It is a high incidence malignant tumor associated with a low survival rate and limited treatment options. Accumulating conclusions indicate that the Wnt signaling pathway plays a vital role in the pathobiological process of HNSCC. The canonical Wnt/β-catenin signaling pathway affects a variety of cellular progression, enabling tumor cells to maintain and further promote the immature stem-like phenotype, proliferate, prolong survival, and gain invasiveness. Genomic studies of head and neck tumors have shown that although β-catenin is not frequently mutated in HNSCC, its activity is not inhibited by mutations in upstream gene encoding β-catenin, NOTCH1, FAT1, and AJUBA. Genetic defects affect the components of the Wnt pathway in oral squamous cell carcinoma (OSCC) and the epigenetic mechanisms that regulate inhibitors of the Wnt pathway. This paper aims to summarize the groundbreaking discoveries and recent advances involving the Wnt signaling pathway and highlight the relevance of this pathway in head and neck squamous cell cancer, which will help provide new insights into improving the treatment of human HNSCC by interfering with the transcriptional signaling of Wnt.


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