scholarly journals Nrf1 is endowed with a dominant tumor-repressing effect onto the Wnt/β-Catenin-dependent and -independent signaling networks in the human liver cancer

2019 ◽  
Author(s):  
Jiayu Chen ◽  
Meng Wang ◽  
Xufang Ru ◽  
Yuancai Xiang ◽  
Yonggang Ren ◽  
...  

ABSTRACTOur previous work revealed that Nrf1α exerts a tumor-repressing effect because its genomic loss (to yield Nrf1α−/−) results in oncogenic activation of Nrf2 and target genes. Interestingly, β-catenin is concurrently activated by loss of Nrf1α in a way similar to β-catenin-driven liver tumor. However, a presumable relationship between Nrf1 and β-catenin is not as yet established. Here, we demonstrate that Nrf1 enhanced ubiquitination of β-catenin for targeting to proteasomal degradation. Conversely, knockdown of Nrf1 by its short-hairpin RNA (shNrf1) caused accumulation of β-catenin so as to translocate the nucleus, allowing activation of a subset of Wnt–β-catenin signaling responsive genes, which leads to the epithelial-mesenchymal transition (EMT) and related cellular processes. Such silencing of Nrf1 resulted in malgrowth of human hepatocellular carcinoma, along with malignant invasion and metastasis to the lung and liver in xenograft model mice. Further transcriptomic sequencing unraveled significant differences in the expression of both Wnt/β-catenin-dependent and -independent responsive genes implicated in the cell process, shape and behavior of the shNrf1-expressing tumor. Notably, we identified that β-catenin is not a target gene of Nrf1, but this CNC-bZIP factor contributes to differential or opposing expression of other critical genes, such as CDH1, Wnt5A, Wnt11A, FZD10, LEF, TCF4, SMAD4, MMP9, PTEN, PI3K, JUN and p53, each of which depends on the positioning of distinct cis-regulatory sequences (e.g., ARE and/or AP-1 binding sites) in the gene promoter contexts. In addition, altered expression profiles of some Wnt–β-catenin signaling proteins were context-dependent, as accompanied by decreased abundances of Nrf1 in the clinic human hepatomas with distinct differentiation. Together, these results corroborate the rationale that Nrf1 acts as a bona fide dominant tumor-repressor, by its intrinsic inhibition of Wnt–β-catenin signaling and relevant independent networks in cancer development and malignant progression.

2020 ◽  
Vol 2020 ◽  
pp. 1-28 ◽  
Author(s):  
Jiayu Chen ◽  
Meng Wang ◽  
Yuancai Xiang ◽  
Xufang Ru ◽  
Yonggang Ren ◽  
...  

Our previous work revealed that Nrf1α exerts a tumor-repressing effect because its genomic loss (to yield Nrf1α-/-) results in oncogenic activation of Nrf2 and target genes. Interestingly, β-catenin is concurrently activated by loss of Nrf1α in a way similar to β-catenin-driven liver tumor. However, a presumable relationship between Nrf1 and β-catenin is not yet established. Here, we demonstrate that Nrf1 enhanced ubiquitination of β-catenin for targeting proteasomal degradation. Conversely, knockdown of Nrf1 by its short hairpin RNA (shNrf1) caused accumulation of β-catenin so as to translocate the nucleus, allowing activation of a subset of Wnt/β-catenin signaling responsive genes, which leads to the epithelial-mesenchymal transition (EMT) and related cellular processes. Such silencing of Nrf1 resulted in malgrowth of human hepatocellular carcinoma, along with malignant invasion and metastasis to the lung and liver in xenograft model mice. Further transcriptomic sequencing unraveled significant differences in the expression of both Wnt/β-catenin-dependent and Wnt/β-catenin-independent responsive genes implicated in the cell process, shape, and behavior of the shNrf1-expressing tumor. Notably, we identified that β-catenin is not a target gene of Nrf1, but this CNC-bZIP factor contributes to differential or opposing expression of other critical genes, such as CDH1, Wnt5A, Wnt11A, FZD10, LEF1, TCF4, SMAD4, MMP9, PTEN, PI3K, JUN, and p53, each of which depends on the positioning of distinct cis-regulatory sequences (e.g., ARE and/or AP-1 binding sites) in the gene promoter contexts. In addition, altered expression profiles of some Wnt/β-catenin signaling proteins were context dependent, as accompanied by decreased abundances of Nrf1 in the clinic human hepatomas with distinct differentiation. Together, these results corroborate the rationale that Nrf1 acts as a bona fide dominant tumor repressor, by its intrinsic inhibition of Wnt/β-catenin signaling and relevant independent networks in cancer development and malignant progression.


2019 ◽  
Vol 21 (Supplement_3) ◽  
pp. iii45-iii46
Author(s):  
W Kim

Abstract BACKGROUND Glioblastoma (GBM) is the most common and aggressive human primary brain malignancy. The key properties of GBM, stemness and invasiveness, are known to be associated with a highly unfavorable prognosis. Notably, the process of epithelial-mesenchymal transition (EMT) is closely related to the progression of GBM. On the basis of reports that 2′-hydroxycinnamaldehyde (HCA) and its derivative, 2′-benzoyloxycinnamaldehyde (BCA), suppresses EMT in several human cancer cells, we sought to evaluate the therapeutic efficacy of HCA and BCA, alone and in combination with temozolomide (TMZ), on GBM tumorspheres (TSs). MATERIAL AND METHODS Two human GBM TSs were treated with HCA, BCA, or TMZ. Therapeutic effects were evaluated by measuring ATP levels, neurosphere formation, 3D-invasion in collagen matrix, and viability. Protein expression profiles after drug treatment were evaluated by western blotting. In vivo anticancer efficacy of drugs was examined in a mouse orthotopic xenograft model. RESULTS Combined treatment of GBM TSs with HCA or BCA and TMZ significantly reduced cell viability, stemness, and invasiveness. Expression levels of stemness-, invasiveness-, and mesenchymal transition-associated markers, Zeb1, N-cadherin, and β-catenin, were also substantially decreased by the combined treatment. The combined treatment also reduced tumor growth in a mouse orthotopic xenograft model. CONCLUSION Our findings suggest that HCA and BCA, combined with TMZ, are potential therapeutic agents in the treatment of GBM.


2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Shan Xing ◽  
Zhi Tian ◽  
Wenying Zheng ◽  
Wenjuan Yang ◽  
Nan Du ◽  
...  

Abstract Background MicroRNAs (miRNAs) show considerable promise as therapeutic agents to improve tumor treatment, as they have been revealed as crucial modulators in tumor progression. However, our understanding of their roles in gastric carcinoma (GC) metastasis is limited. Here, we aimed to identify novel miRNAs involved in GC metastasis and explored their regulatory mechanisms and therapeutic significance in GC. Methods The microRNA expression profiles of GC tumors at different stages and at different metastasis statuses were compared respectively using the stomach adenocarcinoma (STAD) miRNASeq dataset in TCGA. Using the above method, miR-4521 was picked out for further study. miR-4521 expression in GC tissues was examined by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and in situ hybridization (ISH). Highly and lowly invasive cell sublines were established using a repetitive transwell assay. Gain-of-function and loss-of-function analyses were performed to investigate the functions of miR-4521 and its upstream and downstream regulatory mechanisms in vitro and in vivo. Moreover, we investigated the therapeutic role of miR-4521 in a mouse xenograft model. Results In this study, we found that miR-4521 expression was downregulated in GC tissues compared with adjacent normal tissues and that its downregulation was positively correlated with advanced clinical stage, metastasis status and poor patient prognosis. Functional experiments revealed that miR-4521 inhibited GC cell invasion and metastasis in vitro and in vivo. Further studies showed that hypoxia repressed miR-4521 expression via inducing ETS1 and miR-4521 mitigated hypoxia-mediated metastasis, while miR-4521 inactivated the AKT/GSK3β/Snai1 pathway by targeting IGF2 and FOXM1, thereby inhibiting the epithelial-mesenchymal transition (EMT) process and metastasis. In addition, we demonstrated that therapeutic delivery of synthetic miR-4521 suppressed gastric carcinoma progression in vivo. Conclusions Our results suggest an important role for miR-4521 in regulating GC metastasis and hypoxic response of tumor cells as well as the therapeutic significance of this miRNA in GC.


2011 ◽  
Vol 43 (21) ◽  
pp. 1226-1240 ◽  
Author(s):  
Marie-Laure Franco-Montoya ◽  
Olivier Boucherat ◽  
Christelle Thibault ◽  
Bernadette Chailley-Heu ◽  
Roberto Incitti ◽  
...  

Better understanding alveolarization mechanisms could help improve prevention and treatment of diseases characterized by reduced alveolar number. Although signaling through fibroblast growth factor (FGF) receptors is essential for alveolarization, involved ligands are unidentified. FGF18, the expression of which peaks coincidentally with alveolar septation, is likely to be involved. Herein, a mouse model with inducible, lung-targeted FGF18 transgene was used to advance the onset of FGF18 expression peak, and genome-wide expression changes were determined by comparison with littermate controls. Quantitative RT-PCR was used to confirm expression changes of selected up- and downregulated genes and to determine their expression profiles in the course of lung postnatal development. This allowed identifying so-far unknown target genes of the factor, among which a number are known to be involved in alveolarization. The major target was adrenomedullin, a promoter of lung angiogenesis and alveolar development, whose transcript was increased 6.9-fold. Other genes involved in angiogenesis presented marked expression increases, including Wnt2 and cullin2. Although it appeared to favor cell migration notably through enhanced expression of Snai1/2, FGF18 also induced various changes consistent with prevention of epithelial-mesenchymal transition. Together with antifibrotic effects driven by induction of E prostanoid receptor 2 and repression of numerous myofibroblast markers, this could prevent alveolar septation-driving mechanisms from becoming excessive and deleterious. Last, FGF18 up- or downregulated genes of extracellular matrix components and epithelial cell markers previously shown to be up- or downregulated during alveolarization. These findings therefore argue for an involvement of FGF18 in the control of various developmental events during the alveolar stage.


Cancers ◽  
2021 ◽  
Vol 13 (19) ◽  
pp. 4917
Author(s):  
Akihiro Hirao ◽  
Yasushi Sato ◽  
Hironori Tanaka ◽  
Kensei Nishida ◽  
Tetsu Tomonari ◽  
...  

The mechanism of resistance to sorafenib in hepatocellular carcinoma (HCC) remains unclear. We analyzed miRNA expression profiles in sorafenib-resistant HCC cell lines (PLC/PRF5-R1/R2) and parental cell lines (PLC/PRF5) to identify the miRNAs responsible for resistance. Drug sensitivity, migration/invasion capabilities, and epithelial-mesenchymal transition (EMT) properties were analyzed by biochemical methods. The clinical relevance of the target genes to survival in HCC patients were assessed using a public database. Four miRNAs were significantly upregulated in PLC/PRF5-R1/-R2 compared with PLC/PRF5. Among them, miR-125b-5p mimic-transfected PLC/PRF5 cells (PLC/PRF5-miR125b) and showed a significantly higher IC50 for sorafenib compared with controls, while the other miRNA mimics did not. PLC/PRF5-miR125b showed lower E-cadherin and higher Snail and vimentin expression—findings similar to those for PLC/PRF5-R2—which suggests the induction of EMT in those cells. PLC/PRF5-miR125b exhibited significantly higher migration and invasion capabilities and induced sorafenib resistance in an in vivo mouse model. Bioinformatic analysis revealed ataxin-1 as a target gene of miR-125b-5p. PLC/PRF5 cells transfected with ataxin-1 siRNA showed a significantly higher IC50, higher migration/invasion capability, higher cancer stem cell population, and an EMT phenotype. Median overall survival in the low-ataxin-1 patient group was significantly shorter than in the high-ataxin-1 group. In conclusion, miR-125b-5p suppressed ataxin-1 and consequently induced Snail-mediated EMT and stemness, leading to a poor prognosis in HCC patients.


Author(s):  
Shurong Ren ◽  
Qizhen Yue ◽  
Qiubo Wang ◽  
Yanli Zhang ◽  
Bei Zhang

Background: Chronic liver damages from viral infection or alcohol abuse result in liver fibrosis, which is a key pathological event in many types of liver diseases. Discovering new anti-fibrosis agents may provide alternative solutions to manage chronic liver diseases. Methods: We first used CCl4 induced liver fibrosis animal model to evaluate the beneficial effects of Cryptotanshinone (CRY). We next explored target miRNAs regulated by CRY in hepatocytes using microarray. The target miRNA candidate was confirmed with realtime-PCR. We also elucidated the downstream target and pathway directly regulated by the miRNA using luciferase assay, western blotting and Epithelial–Mesenchymal Transition (EMT) markers quantification. Lastly, we confirmed CRY induced expression changes of the target genes in vivo. Results: CRY oral administration markedly alleviated the liver injury caused by CCl4. miRNAs expression profiling and realtime-PCR validation revealed miR-539-3p was directly induced by CRY around 4 folds. The induction of miR-539-3p suppressed SMO expression and antagonized Hedgehog (Hh) pathway. Independently CRY treatment suppressed SMO and inhibited EMT process in hepatocytes. The CRY induced expression changes of both miR-539-3p (~ 2 folds increase) and SMO (~ 60% decrease) in livers were validated in animal model. Conclusion: Our study supported CRY could inhibit liver fibrosis by targeting Hh pathway during EMT. CRY could be used as anti-fibrosis agent candidate for managing chronic liver damages.


Oncogene ◽  
2021 ◽  
Author(s):  
Kaisa-Mari Launonen ◽  
Ville Paakinaho ◽  
Gianluca Sigismondo ◽  
Marjo Malinen ◽  
Reijo Sironen ◽  
...  

AbstractTreatment of prostate cancer confronts resistance to androgen receptor (AR)-targeted therapies. AR-associated coregulators and chromatin proteins hold a great potential for novel therapy targets. Here, we employed a powerful chromatin-directed proteomics approach termed ChIP-SICAP to uncover the composition of chromatin protein network, the chromatome, around endogenous AR in castration resistant prostate cancer (CRPC) cells. In addition to several expected AR coregulators, the chromatome contained many nuclear proteins not previously associated with the AR. In the context of androgen signaling in CRPC cells, we further investigated the role of a known AR-associated protein, a chromatin remodeler SMARCA4 and that of SIM2, a transcription factor without a previous association with AR. To understand their role in chromatin accessibility and AR target gene expression, we integrated data from ChIP-seq, RNA-seq, ATAC-seq and functional experiments. Despite the wide co-occurrence of SMARCA4 and AR on chromatin, depletion of SMARCA4 influenced chromatin accessibility and expression of a restricted set of AR target genes, especially those involved in cell morphogenetic changes in epithelial-mesenchymal transition. The depletion also inhibited the CRPC cell growth, validating SMARCA4’s functional role in CRPC cells. Although silencing of SIM2 reduced chromatin accessibility similarly, it affected the expression of a much larger group of androgen-regulated genes, including those involved in cellular responses to external stimuli and steroid hormone stimulus. The silencing also reduced proliferation of CRPC cells and tumor size in chick embryo chorioallantoic membrane assay, further emphasizing the importance of SIM2 in CRPC cells and pointing to the functional relevance of this potential prostate cancer biomarker in CRPC cells. Overall, the chromatome of AR identified in this work is an important resource for the field focusing on this important drug target.


2021 ◽  
Vol 12 (7) ◽  
Author(s):  
Peng Li Zhou ◽  
Zhengyang Wu ◽  
Wenguang Zhang ◽  
Miao Xu ◽  
Jianzhuang Ren ◽  
...  

AbstractGrowing evidence has indicated that circular RNAs (circRNAs) play a pivotal role as functional RNAs in diverse cancers. However, most circRNAs involved in esophageal squamous cell carcinoma (ESCC) remain undefined, and the underlying molecular mechanisms mediated by circRNAs are largely unclear. Here, we screened human circRNA expression profiles in ESCC tissues and found significantly increased expression of hsa_circ_0000277 (termed circPDE3B) in ESCC tissues and cell lines compared to the normal controls. Moreover, higher circPDE3B expression in patients with ESCC was correlated with advanced tumor-node-metastasis (TNM) stage and dismal prognosis. Functional experiments demonstrated that circPDE3B promoted the tumorigenesis and metastasis of ESCC cells in vitro and in vivo. Mechanistically, bioinformatics analysis, a dual-luciferase reporter assay, and anti-AGO2 RNA immunoprecipitation showed that circPDE3B could act as a competing endogenous RNA (ceRNA) by harboring miR-4766-5p to eliminate the inhibitory effect on the target gene laminin α1 (LAMA1). In addition, LAMA1 was significantly upregulated in ESCC tissues and was positively associated with the aggressive oncogenic phenotype. More importantly, rescue experiments revealed that the oncogenic role of circPDE3B in ESCC is partly dependent on the miR-4766-5p/LAMA1 axis. Furthermore, bioinformatics analysis combined with validation experiments showed that epithelial-mesenchymal transition (EMT) activation was involved in the oncogenic functions of the circPDE3B–miR-4766-5p/LAMA1 axis in ESCC. Taken together, we demonstrate for the first time that the circPDE3B/miR-4766-5p/LAMA1 axis functions as an oncogenic factor in promoting ESCC cell proliferation, migration, and invasion by inducing EMT, implying its potential prognostic and therapeutic significance in ESCC.


2021 ◽  
Vol 22 (14) ◽  
pp. 7627
Author(s):  
Tingting Shi ◽  
Asahiro Morishita ◽  
Hideki Kobara ◽  
Tsutomu Masaki

Cholangiocarcinoma (CCA), an aggressive malignancy, is typically diagnosed at an advanced stage. It is associated with dismal 5-year postoperative survival rates, generating an urgent need for prognostic and diagnostic biomarkers. MicroRNAs (miRNAs) are a class of non-coding RNAs that are associated with cancer regulation, including modulation of cell cycle progression, apoptosis, metastasis, angiogenesis, autophagy, therapy resistance, and epithelial–mesenchymal transition. Several miRNAs have been found to be dysregulated in CCA and are associated with CCA-related risk factors. Accumulating studies have indicated that the expression of altered miRNAs could act as oncogenic or suppressor miRNAs in the development and progression of CCA and contribute to clinical diagnosis and prognosis prediction as potential biomarkers. Furthermore, miRNAs and their target genes also contribute to targeted therapy development and aid in the determination of drug resistance mechanisms. This review aims to summarize the roles of miRNAs in the pathogenesis of CCA, their potential use as biomarkers of diagnosis and prognosis, and their utilization as novel therapeutic targets in CCA.


2005 ◽  
Vol 16 (4) ◽  
pp. 1987-2002 ◽  
Author(s):  
Ulrich Valcourt ◽  
Marcin Kowanetz ◽  
Hideki Niimi ◽  
Carl-Henrik Heldin ◽  
Aristidis Moustakas

Epithelial-mesenchymal transition (EMT) contributes to normal tissue patterning and carcinoma invasiveness. We show that transforming growth factor (TGF)-β/activin members, but not bone morphogenetic protein (BMP) members, can induce EMT in normal human and mouse epithelial cells. EMT correlates with the ability of these ligands to induce growth arrest. Ectopic expression of all type I receptors of the TGF-β superfamily establishes that TGF-β but not BMP pathways can elicit EMT. Ectopic Smad2 or Smad3 together with Smad4 enhanced, whereas dominant-negative forms of Smad2, Smad3, or Smad4, and wild-type inhibitory Smad7, blocked TGF-β–induced EMT. Transcriptomic analysis of EMT kinetics identified novel TGF-β target genes with ligand-specific responses. Using a TGF-β type I receptor that cannot activate Smads nor induce EMT, we found that Smad signaling is critical for regulation of all tested gene targets during EMT. One such gene, Id2, whose expression is repressed by TGF-β1 but induced by BMP-7 is critical for regulation of at least one important myoepithelial marker, α-smooth muscle actin, during EMT. Thus, based on ligand-specific responsiveness and evolutionary conservation of the gene expression patterns, we begin deciphering a genetic network downstream of TGF-β and predict functional links to the control of cell proliferation and EMT.


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