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Des R Richardson - One of the best experts on this subject based on the ideXlab platform.
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NDRG1 suppresses basal and hypoxia induced autophagy at both the initiation and degradation stages and sensitizes pancreatic cancer cells to lysosomal membrane permeabilization
Biochimica et Biophysica Acta, 2020Co-Authors: Sumit Sahni, Des R Richardson, Kyung Chan Park, Patric J. Jansson, Josef Gillson, Shannon Chiang, Lionel Yi Wen LeckAbstract:Abstract Background N-myc downstream regulated gene 1 (NDRG1) is an established stress-response protein. This study investigated the effects of NDRG1 on autophagic degradation and how this can be therapeutically exploited. Methods Cell culture, western analysis, confocal microscopy, acridine orange staining, cholesterol determination, cellular proliferation assessment and combination index (CI) estimation. Results NDRG1 expression suppressed autophagic degradation and autolysosome formation, measured by increased p62 expression and reduced co-localization between the well-characterized, autophagosomal and lysosomal markers, LC3 and LAMP2, respectively. NDRG1 elicited autophagic suppression at the initiation stage of autophagy. The NDRG1-inducer and anti-cancer agent, di-2-pyridylketone 4,4,-dimethyl-3-thiosemicarbazone (Dp44mT), was able to induce lysosomal membrane permeabilization (LMP). Over-expression of NDRG1 further sensitized cells to LMP mediated by both Dp44mT, or the redox active Dp44mT‑copper complex. This sensitization may be mediated via a decrease in cholesterol levels upon NDRG1 expression, as cholesterol stabilizes lysosomal membranes. However, the effect of NDRG1 on cholesterol appeared independent of the key energy homeostasis sensor, 5’ AMP-activated protein kinase (AMPK), whose activation was significantly (p Conclusions and general significance Collectively, this study demonstrated a dual-inhibitory mechanism of NDRG1 on autophagic activity, and that NDRG1 expression sensitized cells to Dp44mT-induced LMP. Considering the ability of Dp44mT to inhibit autophagy, studies demonstrated the potential of combination therapy for cancer treatment of Dp44mT with Gemcitabine.
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the metastasis suppressor NDRG1 down regulates the epidermal growth factor receptor via a lysosomal mechanism by up regulating mitogen inducible gene 6
Journal of Biological Chemistry, 2019Co-Authors: Sharleen V Menezes, Zaklina Kovacevic, Des R RichardsonAbstract:The metastasis suppressor, N-Myc downstream-regulated gene-1 (NDRG1) inhibits a plethora of oncogenic signaling pathways by down-regulating the epidermal growth factor receptor (EGFR). Herein, we examined the mechanism involved in NDRG1-mediated EGFR down-regulation. NDRG1 overexpression potently increased the levels of mitogen-inducible gene 6 (MIG6), which inhibits EGFR and facilitates its lysosomal processing and degradation. Conversely, silencing NDRG1 in multiple human cancer cell types decreased MIG6 expression, demonstrating the regulatory role of NDRG1. Further, NDRG1 overexpression facilitated MIG6-EGFR association in the cytoplasm, possibly explaining the significantly (p <0.001) increased half-life of MIG6 from 1.6 ± 0.2 h under control conditions to 7.9 ± 0.4 h after NDRG1 overexpression. The increased MIG6 levels enhanced EGFR co-localization with the late endosome/lysosomal marker, lysosomal-associated membrane protein 2 (LAMP2). An increase in EGFR levels after MIG6 silencing was particularly apparent when NDRG1 was overexpressed, suggesting a role for MIG6 in NDRG1-mediated down-regulation of EGFR. Silencing phosphatase and tensin homolog (PTEN), which facilitates early to late endosome maturation, decreased MIG6, and also increased EGFR levels in both the presence and absence of NDRG1 overexpression. These results suggest a role for PTEN in regulating MIG6 expression. Anti-tumor drugs of the di-2-pyridylketone thiosemicarbazone class that activate NDRG1 expression also potently increased MIG6 and induced its cytosolic co-localization with NDRG1. This was accompanied by a decrease in activated and total EGFR levels and its redistribution to late endosomes/lysosomes. In conclusion, NDRG1 promotes EGFR down-regulation through the EGFR inhibitor MIG6, which leads to late endosomal/lysosomal processing of EGFR.
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Pharmacological targeting and the diverse functions of the metastasis suppressor, NDRG1, in cancer.
Free radical biology & medicine, 2019Co-Authors: Kyung Chan Park, Zaklina Kovacevic, Jasmina Paluncic, Des R RichardsonAbstract:Abstract N-myc downstream regulated gene-1 (NDRG1) is a potent metastasis suppressor that is regulated by hypoxia, metal ions including iron, the free radical nitric oxide (NO.), and various stress stimuli. This intriguing molecule exhibits diverse functions in cancer, inhibiting epithelial-mesenchymal transition (EMT), cell migration and angiogenesis by modulation of a plethora of oncogenes via cellular signaling. Thus, pharmacological targeting of NDRG1 signaling in cancer is a promising therapeutic strategy. Of note, novel anti-tumor agents of the di-2-pyridylketone thiosemicarbazone series, which exert the “double punch” mechanism by binding metal ions to form redox-active complexes, have been demonstrated to markedly up-regulate NDRG1 expression in cancer cells. This review describes the mechanisms underlying NDRG1 modulation by the thiosemicarbazones and the diverse effects NDRG1 exerts in cancer. As a major induction mechanism, iron depletion appears critical, with NO. also inducing NDRG1 through its ability to bind iron and generate dinitrosyl-dithiol iron complexes, which are then effluxed from cells. Apart from its potent anti-metastatic role, several studies have reported a pro-oncogenic role of NDRG1 in a number of cancer-types. Hence, it has been suggested that NDRG1 plays pleiotropic roles depending on the cancer-type. The molecular mechanism(s) underlying NDRG1 pleiotropy remain elusive, but are linked to differential regulation of WNT signaling and potentially differential interaction with the tumor suppressor, PTEN. This review discusses NDRG1 induction mechanisms by metal ions and NO. and both the anti- and possible pro-oncogenic functions of NDRG1 in multiple cancer-types and compares the opposite effects this protein exerts on cancer progression.
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Identification of differential phosphorylation and sub-cellular localization of the metastasis suppressor, NDRG1.
Biochimica et biophysica acta. Molecular basis of disease, 2018Co-Authors: Kyung Chan Park, Zaklina Kovacevic, Sharleen V Menezes, Danuta S. Kalinowski, Sumit Sahni, Patric J. Jansson, Des R RichardsonAbstract:Abstract The metastasis suppressor, N-myc downstream regulated gene-1 (NDRG1), exhibits pleiotropic activity, inhibiting metastasis of various tumor-types, while being correlated with metastasis in others. Notably, NDRG1 phosphorylation and cleavage are associated with its function, although it is unclear if these modifications occur universally, or selectively, in different cancer cell-types and if it contributes to its pleiotropy. Considering the suggested DNA repair role of nuclear NDRG1, the effects of the above post-translational modifications on its nuclear localization was examined. Herein, the full-length (FL) and truncated (T) NDRG1 isoforms were detected using a C-terminus-directed antibody, while only the FL isoform was identified using an N-terminus-directed antibody. For the first time, we demonstrate that the expression of the NDRG1 FL and T forms occurs in all cancer cell-types examined, as does its phosphorylation (p-NDRG1) at Ser330 and Thr346. The FL isoform localized highly in the nucleus compared to the T isoform. Moreover, p-NDRG1 (Ser330) was also markedly localized in the nucleus, while p-NDRG1 (Thr346) was predominantly cytoplasmic in all cell-types. These results indicate the N-terminus region and phosphorylation at Ser330 could be crucial for NDRG1 nuclear localization and function. PTEN silencing indicated that p-NDRG1 (Thr346) could be regulated differentially in different tumor cell-types, indicating PTEN may be involved in the mechanism(s) underlying the pleiotropic activity of NDRG1. Finally, therapeutics of the di-2-pyridylketone thiosemicarbazone class increased nuclear NDRG1 isoforms (FL and T) detected by the C-terminus-directed antibody in HepG2 cells, while having no significant effect in PC3 cells, indicating differential activity depending on the cell-type.
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the metastasis suppressor NDRG1 inhibits stemness of colorectal cancer via down regulation of nuclear β catenin and cd44
Oncotarget, 2015Co-Authors: Xiongzhi Wangpu, Zaklina Kovacevic, Jing Sun, Wensheng Liu, Fei Yue, Xiao Yang, Jingkun Zhao, Shaopei Guan, Runsen Jin, Des R RichardsonAbstract:// Xiongzhi Wangpu 1, 2, 3 , Xiao Yang 1, 2, 4 , Jingkun Zhao 1, 2 , Jiaoyang Lu 1, 2 , Shaopei Guan 1, 4 , Jun Lu 1, 2 , Zaklina Kovacevic 3 , Wensheng Liu 1 , Lan Mi 1 , Runsen Jin 1 , Jing Sun 1, 2 , Fei Yue 1, 2 , Junjun Ma 1, 2 , Aiguo Lu 1, 2, 4 , Des R. Richardson 3 , Lishun Wang 5 , Minhua Zheng 1, 2, 4 1 Department of General Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China 2 Shanghai Minimally Invasive Surgery Center, Shanghai, 200025, China 3 Molecular Pharmacology and Pathology Program, Department of Pathology and Bosch Institute, University of Sydney, Sydney, New South Wales, 2006, Australia 4 Shanghai Institute of Digestive Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China 5 The Division of Translational Medicine, Minhang Hospital, Fudan University, Shanghai, 201199, China Correspondence to: Minhua Zheng, e-mail: wangpuxz@hotmail.com Lishun Wang, e-mail: lishunwang@fudan.edu.cn Des R. Richardson, e-mail: d.richardson@med.usyd.edu.au Keywords: β-catenin, colorectal cancer, NDRG1, stem cell-like property, tumorigenesis Received: March 18, 2015 Accepted: September 04, 2015 Published: September 18, 2015 ABSTRACT N-myc downstream-regulated gene 1 (NDRG1), has been identified as an important metastasis suppressor for colorectal cancer (CRC). In this study, we investigated: (1) the effects of NDRG1 on CRC stemness and tumorigenesis; (2) the molecular mechanisms involved; and (3) the relationship between NDRG1 expression and colorectal cancer prognosis. Our investigation demonstrated that CRC cells with silenced NDRG1 showed more tumorigenic ability and stem cell-like properties, such as: colony and sphere formation, chemoresistance, cell invasion, high expression of CD44, and tumorigenicity in vivo . Moreover, NDRG1 silencing reduced β-catenin expression on the cell membrane, while increasing its nuclear expression. The anti-tumor activity of NDRG1 was demonstrated to be mediated by preventing β-catenin nuclear translocation, as silencing of this latter molecule could reverse the effects of silencing NDRG1 expression. NDRG1 expression was also demonstrated to be negatively correlated to CRC prognosis. In addition, there was a negative correlation between NDRG1 and nuclear β-catenin and also NDRG1 and CD44 expression in clinical CRC specimens. Taken together, our investigation demonstrates that the anti-metastatic activity of NDRG1 in CRC occurs through the down-regulation of nuclear β-catenin and suggests that NDRG1 is a significant therapeutic target.
Liang-chuan Lai - One of the best experts on this subject based on the ideXlab platform.
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Different effects of long noncoding RNA NDRG1-OT1 fragments on NDRG1 transcription in breast cancer cells under hypoxia.
RNA biology, 2018Co-Authors: Ching-ching Yeh, Jun-liang Luo, Nam Nhut Phan, Yi-chun Cheng, Lu-ping Chow, Mong-hsun Tsai, Eric Y. Chuang, Liang-chuan LaiAbstract:Hypoxia plays a crucial role in the aggressiveness of solid tumors by driving multiple signaling pathways. Recently, long non-coding RNA (lncRNA) has been reported to promote or inhibit tumor aggressiveness by regulating gene expression. Previous studies in our laboratory found that the lncRNA NDRG1-OT1 is significantly up-regulated under hypoxia and inhibits its target gene NDRG1 at both the mRNA and protein levels. At the protein level, NDRG1-OT1 increases NDRG1 degradation via ubiquitin-mediated proteolysis. However, the repressive mechanism of NDRG1 at the RNA level is still unknown. Therefore, the purpose of this study was to study how NDRG1-OT1 transcriptionally regulates its target gene NDRG1. Luciferase reporter assays showed that NDRG1-OT1 decreased NDRG1 promoter activities. Mass spectrometry, bioinformatics tools, genetic manipulation, and immunoblotting were used to identify the interacting proteins. Surprisingly, different fragments of NDRG1-OT1 had opposite effects on NDRG1. The first quarter fragment (1–149 nt) of NDRG1-OT1 had no effect on the NDRG1 promoter; the second quarter fragment (150–263 nt) repressed NDRG1 by increasing the binding affinity of HNRNPA1; the third quarter fragment (264–392 nt) improved NDRG1 promoter activity by recruiting HIF-1α; the fourth quarter fragment (393–508 nt) down-regulated NDRG1 promoter activity via down-regulation of KHSRP under hypoxia. In summary, we have found a novel mechanism by which different fragments of the same lncRNA can cause opposite effects within the same target gene.
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the hypoxia responsive lncrna ndrg ot1 promotes NDRG1 degradation via ubiquitin mediated proteolysis in breast cancer cells
Oncotarget, 2017Co-Authors: Hsinchen Lin, Ching-ching Yeh, Mong-hsun Tsai, Eric Y. Chuang, Loyun Chao, Hunghsin Chen, Liang-chuan LaiAbstract:Hypoxia can lead to solid tumor aggressiveness by driving multiple signaling pathways. Long non-coding RNAs respond to several extrinsic stimuli, causing changes in cancer cells by participating in multiple steps of gene expression. However, genomic profiling of long non-coding RNAs regulated by oxygen in breast cancer remained unclear. Therefore, the aims of this study were to identify oxygen-responsive long non-coding RNAs in breast cancer cells, and to delineate their regulatory mechanisms. The expression profiling of long non-coding RNAs in breast cancer cells growing under normoxic, hypoxic, and re-oxygenated conditions was examined using next-generation sequencing technology. Four hundred and seventy-two lncRNAs oxygen-responsive lncRNAs were identified. After examining the top three differentially expressed lncRNAs in hypoxia, we selected N-Myc Downstream Regulated Gene 1-Overlapping 1 (NDRG1-OT1) for further study, especially the most responsive isoform, NDRG1-OT1_v4. We overexpressed NDRG1-OT1_v4 under normoxia and performed microarray analysis to identify 108 NDRG1-OT1_v4 regulated genes and their functions. Among these genes, we found that both NDRG1 mRNA expression and NDRG1 protein levels were inhibited by NDRG1-OT1_v4. Finally, we used co-immunoprecipitation to show that NDRG1-OT1_v4 destabilizes NDRG1 by promoting ubiquitin-mediated proteolysis. Our findings reveal a new type of epigenetic regulation of NDRG1 by NDRG1-OT1_v4 in breast cancer cells.
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Abstract 975: Hypoxic long noncoding RNA NDRG1-OT1 inhibit NDRG1 in MCF-7 breast cancer cell line
Molecular and Cellular Biology Genetics, 2016Co-Authors: Hsinchen Lin, Mong-hsun Tsai, Liang-chuan Lai, Hunghsin Chen, Hsing-guang Chen, Mei-hung Chang, Eric Y. ChungAbstract:Hypoxia is a crucial factor that associated with solid tumor progression by driving multiple signaling pathway. Our lab previously reported that NDRG1 was oxygen-responsive genes and could affect cellular function in a breast cancer cell line MCF-7. Long-non coding RNAs (lncRNAs) have recently emerged as important regulators of tumor progression by participating in several process of gene expression. However, it is unclear whether lncRNAs are responsed to oxygen concentrations in breast cancer. Therefore, the aim of this study is to identify lncRNAs which are responsive upon changes in oxygen concentrations, and its regulatory mechanism in the breast cancer MCF-7 cells. We investigated the differentially expressed lncRNAs in different oxygen concentrations using next-generation sequencing (NGS) and validated these results through quantitative reverse transcription polymerase chain reaction (qRT-PCR). We found an lncRNA, NDRG1-OT1, that was up-regulated during hypoxia and down-regulated during reoxygenation. Next, we identified the differentially expressed genes regulated by NDRG1-OT1 using microarrays and confirmed these results through qRT-PCR and Western blotting. We found an oxygen responsive gene, NDRG1, was inhibited by NDRG1-OT1. Furthermore, Ingenuity Pathway Analysis(IPA) indicated that NDRG1-OT1 could involve in the Ubiquitin-proteasome pathway. We considered NDRG1-OT1 might regulate NDRG1 stability and ubiquitination, and we are proving these possibility by immunoblotting and immunoprecipitation. These findings may provide new insights into epigenetic regulation of breast cancer during hypoxia. Citation Format: Hsin-Chen Lin, Liang-Chuan Lai, Hsing-Guang Chen, Hung-Hsin Chen, Mei-Hung Chang, Mong-Hsun Tsai, Eric Y. Chung. Hypoxic long noncoding RNA NDRG1-OT1 inhibit NDRG1 in MCF-7 breast cancer cell line. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 975.
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Aryl Hydrocarbon Receptor Activates NDRG1 Transcription under Hypoxia in Breast Cancer Cells.
Scientific reports, 2016Co-Authors: Wei Yung Huang, Mong-hsun Tsai, Eric Y. Chuang, Loyun Chao, Ya Chu Chang, Qian Yu Kuok, Shih Ting Bai, Yuh Pyng Sher, Liang-chuan LaiAbstract:Hypoxia has been intensively investigated over the past several decades based on the observations that hypoxic tumors are more resistant to therapy and have a worse prognosis. Previously, we reported that N-myc downstream-regulated gene 1 (NDRG1) is strongly up-regulated under hypoxia and may play an important role in tumor adaptation to fluctuating oxygen concentrations. However, the regulatory mechanism of NDRG1 under hypoxia remains elusive. Therefore, the purpose of this study was to identify the transcription factors that regulate NDRG1 and to investigate the functional roles of NDRG1 in hypoxia. We showed that binding sites of aryl hydrocarbon receptor (AHR) were predicted in the NDRG1 promoter. Nuclear AHR was up-regulated in the presence of cobalt and hypoxia. AHR translocated to nuclei and bound between base pairs −412 and −388 of the NDRG1 promoter in hypoxia. Moreover, hypoxia-mimetic induction of NDRG1 was attenuated by knockdown of AHR expression. Also, overexpression of AHR facilitated cell proliferation and migration via up-regulation of NDRG1. These results showed for the first time that AHR positively regulates NDRG1 transcription through an AHR binding site by way of hypoxia-mimetic signaling, which may lead to development of a specific therapeutic regimen to prevent tumor malignancy under hypoxia.
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abstract 1983 aryl hydrocarbon receptor activates NDRG1 transcription under hypoxia in breast cancer cells
Cancer Research, 2015Co-Authors: Wei Yung Huang, Mong-hsun Tsai, Eric Y. Chuang, Liang-chuan LaiAbstract:Proceedings: AACR 106th Annual Meeting 2015; April 18-22, 2015; Philadelphia, PA Hypoxia has been intensively investigated over past decades based on the observations that hypoxic tumors were more resistant to therapy and had a worse prognosis. Previously, we reported that N-myc downstream-regulated gene 1 (NDRG1) was strongly up-regulated under hypoxia and may play an important role in tumor adaptation to fluctuation of oxygen concentrations. However, the regulatory mechanism of NDRG1 under hypoxia remains elusive. Therefore, the purpose of this study is to identify the novel transcription factors that regulate NDRG1 and to investigate the functional roles of NDRG1 in hypoxia. In silico analysis predicted binding sites of aryl hydrocarbon receptor (AHR) existing in the NDRG1 promoter. Western blotting showed that nuclear AHR was up-regulated in the presence of cobalt and hypoxia. Immunofluorescence staining and chromatin immunoprecipitation assays showed that AHR translocated to nuclei and bound to NDRG1 promoter in hypoxia. Luciferase reporter assays further showed that the binding site of AHR at -412 ∼ -388 bp played a crucial role in regulating NDRG1 under hypoxia-mimicking conditions. Moreover, hypoxia-mimetic induction of NDRG1 by was attenuated by knockdown of AHR expression using short interfering RNA. Also, overexpression of AHR facilitated cell proliferation and migration via up-regulation of NDRG1, whereas shRNA knockdown of NDRG1 reduced cell growth and motility. In summary, these results showed for the first time that AHR positively regulates NDRG1 transcription through a AHR binding site by hypoxia-mimetic signaling, which may lead to development of a specific therapeutic regime to prevent tumor malignancy under hypoxia. Citation Format: En-Yu Li, Wei-Yung Huang, Mong-Hsun Tsai, Eric Y. Chuang, Liang-Chuan Lai. Aryl hydrocarbon receptor activates NDRG1 transcription under hypoxia in breast cancer cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1983. doi:10.1158/1538-7445.AM2015-1983
Zaklina Kovacevic - One of the best experts on this subject based on the ideXlab platform.
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the metastasis suppressor NDRG1 down regulates the epidermal growth factor receptor via a lysosomal mechanism by up regulating mitogen inducible gene 6
Journal of Biological Chemistry, 2019Co-Authors: Sharleen V Menezes, Zaklina Kovacevic, Des R RichardsonAbstract:The metastasis suppressor, N-Myc downstream-regulated gene-1 (NDRG1) inhibits a plethora of oncogenic signaling pathways by down-regulating the epidermal growth factor receptor (EGFR). Herein, we examined the mechanism involved in NDRG1-mediated EGFR down-regulation. NDRG1 overexpression potently increased the levels of mitogen-inducible gene 6 (MIG6), which inhibits EGFR and facilitates its lysosomal processing and degradation. Conversely, silencing NDRG1 in multiple human cancer cell types decreased MIG6 expression, demonstrating the regulatory role of NDRG1. Further, NDRG1 overexpression facilitated MIG6-EGFR association in the cytoplasm, possibly explaining the significantly (p <0.001) increased half-life of MIG6 from 1.6 ± 0.2 h under control conditions to 7.9 ± 0.4 h after NDRG1 overexpression. The increased MIG6 levels enhanced EGFR co-localization with the late endosome/lysosomal marker, lysosomal-associated membrane protein 2 (LAMP2). An increase in EGFR levels after MIG6 silencing was particularly apparent when NDRG1 was overexpressed, suggesting a role for MIG6 in NDRG1-mediated down-regulation of EGFR. Silencing phosphatase and tensin homolog (PTEN), which facilitates early to late endosome maturation, decreased MIG6, and also increased EGFR levels in both the presence and absence of NDRG1 overexpression. These results suggest a role for PTEN in regulating MIG6 expression. Anti-tumor drugs of the di-2-pyridylketone thiosemicarbazone class that activate NDRG1 expression also potently increased MIG6 and induced its cytosolic co-localization with NDRG1. This was accompanied by a decrease in activated and total EGFR levels and its redistribution to late endosomes/lysosomes. In conclusion, NDRG1 promotes EGFR down-regulation through the EGFR inhibitor MIG6, which leads to late endosomal/lysosomal processing of EGFR.
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Pharmacological targeting and the diverse functions of the metastasis suppressor, NDRG1, in cancer.
Free radical biology & medicine, 2019Co-Authors: Kyung Chan Park, Zaklina Kovacevic, Jasmina Paluncic, Des R RichardsonAbstract:Abstract N-myc downstream regulated gene-1 (NDRG1) is a potent metastasis suppressor that is regulated by hypoxia, metal ions including iron, the free radical nitric oxide (NO.), and various stress stimuli. This intriguing molecule exhibits diverse functions in cancer, inhibiting epithelial-mesenchymal transition (EMT), cell migration and angiogenesis by modulation of a plethora of oncogenes via cellular signaling. Thus, pharmacological targeting of NDRG1 signaling in cancer is a promising therapeutic strategy. Of note, novel anti-tumor agents of the di-2-pyridylketone thiosemicarbazone series, which exert the “double punch” mechanism by binding metal ions to form redox-active complexes, have been demonstrated to markedly up-regulate NDRG1 expression in cancer cells. This review describes the mechanisms underlying NDRG1 modulation by the thiosemicarbazones and the diverse effects NDRG1 exerts in cancer. As a major induction mechanism, iron depletion appears critical, with NO. also inducing NDRG1 through its ability to bind iron and generate dinitrosyl-dithiol iron complexes, which are then effluxed from cells. Apart from its potent anti-metastatic role, several studies have reported a pro-oncogenic role of NDRG1 in a number of cancer-types. Hence, it has been suggested that NDRG1 plays pleiotropic roles depending on the cancer-type. The molecular mechanism(s) underlying NDRG1 pleiotropy remain elusive, but are linked to differential regulation of WNT signaling and potentially differential interaction with the tumor suppressor, PTEN. This review discusses NDRG1 induction mechanisms by metal ions and NO. and both the anti- and possible pro-oncogenic functions of NDRG1 in multiple cancer-types and compares the opposite effects this protein exerts on cancer progression.
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Identification of differential phosphorylation and sub-cellular localization of the metastasis suppressor, NDRG1.
Biochimica et biophysica acta. Molecular basis of disease, 2018Co-Authors: Kyung Chan Park, Zaklina Kovacevic, Sharleen V Menezes, Danuta S. Kalinowski, Sumit Sahni, Patric J. Jansson, Des R RichardsonAbstract:Abstract The metastasis suppressor, N-myc downstream regulated gene-1 (NDRG1), exhibits pleiotropic activity, inhibiting metastasis of various tumor-types, while being correlated with metastasis in others. Notably, NDRG1 phosphorylation and cleavage are associated with its function, although it is unclear if these modifications occur universally, or selectively, in different cancer cell-types and if it contributes to its pleiotropy. Considering the suggested DNA repair role of nuclear NDRG1, the effects of the above post-translational modifications on its nuclear localization was examined. Herein, the full-length (FL) and truncated (T) NDRG1 isoforms were detected using a C-terminus-directed antibody, while only the FL isoform was identified using an N-terminus-directed antibody. For the first time, we demonstrate that the expression of the NDRG1 FL and T forms occurs in all cancer cell-types examined, as does its phosphorylation (p-NDRG1) at Ser330 and Thr346. The FL isoform localized highly in the nucleus compared to the T isoform. Moreover, p-NDRG1 (Ser330) was also markedly localized in the nucleus, while p-NDRG1 (Thr346) was predominantly cytoplasmic in all cell-types. These results indicate the N-terminus region and phosphorylation at Ser330 could be crucial for NDRG1 nuclear localization and function. PTEN silencing indicated that p-NDRG1 (Thr346) could be regulated differentially in different tumor cell-types, indicating PTEN may be involved in the mechanism(s) underlying the pleiotropic activity of NDRG1. Finally, therapeutics of the di-2-pyridylketone thiosemicarbazone class increased nuclear NDRG1 isoforms (FL and T) detected by the C-terminus-directed antibody in HepG2 cells, while having no significant effect in PC3 cells, indicating differential activity depending on the cell-type.
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the metastasis suppressor NDRG1 inhibits stemness of colorectal cancer via down regulation of nuclear β catenin and cd44
Oncotarget, 2015Co-Authors: Xiongzhi Wangpu, Zaklina Kovacevic, Jing Sun, Wensheng Liu, Fei Yue, Xiao Yang, Jingkun Zhao, Shaopei Guan, Runsen Jin, Des R RichardsonAbstract:// Xiongzhi Wangpu 1, 2, 3 , Xiao Yang 1, 2, 4 , Jingkun Zhao 1, 2 , Jiaoyang Lu 1, 2 , Shaopei Guan 1, 4 , Jun Lu 1, 2 , Zaklina Kovacevic 3 , Wensheng Liu 1 , Lan Mi 1 , Runsen Jin 1 , Jing Sun 1, 2 , Fei Yue 1, 2 , Junjun Ma 1, 2 , Aiguo Lu 1, 2, 4 , Des R. Richardson 3 , Lishun Wang 5 , Minhua Zheng 1, 2, 4 1 Department of General Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China 2 Shanghai Minimally Invasive Surgery Center, Shanghai, 200025, China 3 Molecular Pharmacology and Pathology Program, Department of Pathology and Bosch Institute, University of Sydney, Sydney, New South Wales, 2006, Australia 4 Shanghai Institute of Digestive Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China 5 The Division of Translational Medicine, Minhang Hospital, Fudan University, Shanghai, 201199, China Correspondence to: Minhua Zheng, e-mail: wangpuxz@hotmail.com Lishun Wang, e-mail: lishunwang@fudan.edu.cn Des R. Richardson, e-mail: d.richardson@med.usyd.edu.au Keywords: β-catenin, colorectal cancer, NDRG1, stem cell-like property, tumorigenesis Received: March 18, 2015 Accepted: September 04, 2015 Published: September 18, 2015 ABSTRACT N-myc downstream-regulated gene 1 (NDRG1), has been identified as an important metastasis suppressor for colorectal cancer (CRC). In this study, we investigated: (1) the effects of NDRG1 on CRC stemness and tumorigenesis; (2) the molecular mechanisms involved; and (3) the relationship between NDRG1 expression and colorectal cancer prognosis. Our investigation demonstrated that CRC cells with silenced NDRG1 showed more tumorigenic ability and stem cell-like properties, such as: colony and sphere formation, chemoresistance, cell invasion, high expression of CD44, and tumorigenicity in vivo . Moreover, NDRG1 silencing reduced β-catenin expression on the cell membrane, while increasing its nuclear expression. The anti-tumor activity of NDRG1 was demonstrated to be mediated by preventing β-catenin nuclear translocation, as silencing of this latter molecule could reverse the effects of silencing NDRG1 expression. NDRG1 expression was also demonstrated to be negatively correlated to CRC prognosis. In addition, there was a negative correlation between NDRG1 and nuclear β-catenin and also NDRG1 and CD44 expression in clinical CRC specimens. Taken together, our investigation demonstrates that the anti-metastatic activity of NDRG1 in CRC occurs through the down-regulation of nuclear β-catenin and suggests that NDRG1 is a significant therapeutic target.
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The role of NDRG1 in the pathology and potential treatment of human cancers
Journal of clinical pathology, 2013Co-Authors: Donghun Bae, Zaklina Kovacevic, Danuta S. Kalinowski, Sumit Sahni, Patric J. Jansson, Michael L.-h. Huang, C. Soon Lee, Des R RichardsonAbstract:N-myc downstream regulated gene 1 (NDRG1) has been well characterised to act as a metastatic suppressor in a number of human cancers. It has also been implicated to have a significant function in a number of physiological processes such as cellular differentiation and cell cycle. In this review, we discuss the role of NDRG1 in cancer pathology. NDRG1 was observed to be downregulated in the majority of cancers. Moreover, the expression of NDRG1 was found to be significantly lower in neoplastic tissues as compared with normal tissues. The most important function of NDRG1 in inhibiting tumour progression is associated with its ability to suppress metastasis. However, it has also been shown to have important effects on other stages of cancer progression (primary tumour growth and angiogenesis). Recently, novel iron chelators with selective antitumour activity (ie, Dp44mT, DpC) were shown to upregulate NDRG1 in cancer cells. Moreover, Dp44mT showed its antimetastatic potential only in cells expressing NDRG1, making this protein an important therapeutic target for cancer chemotherapy. This observation has led to increased interest in the examination of these novel anticancer agents.
Mong-hsun Tsai - One of the best experts on this subject based on the ideXlab platform.
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Different effects of long noncoding RNA NDRG1-OT1 fragments on NDRG1 transcription in breast cancer cells under hypoxia.
RNA biology, 2018Co-Authors: Ching-ching Yeh, Jun-liang Luo, Nam Nhut Phan, Yi-chun Cheng, Lu-ping Chow, Mong-hsun Tsai, Eric Y. Chuang, Liang-chuan LaiAbstract:Hypoxia plays a crucial role in the aggressiveness of solid tumors by driving multiple signaling pathways. Recently, long non-coding RNA (lncRNA) has been reported to promote or inhibit tumor aggressiveness by regulating gene expression. Previous studies in our laboratory found that the lncRNA NDRG1-OT1 is significantly up-regulated under hypoxia and inhibits its target gene NDRG1 at both the mRNA and protein levels. At the protein level, NDRG1-OT1 increases NDRG1 degradation via ubiquitin-mediated proteolysis. However, the repressive mechanism of NDRG1 at the RNA level is still unknown. Therefore, the purpose of this study was to study how NDRG1-OT1 transcriptionally regulates its target gene NDRG1. Luciferase reporter assays showed that NDRG1-OT1 decreased NDRG1 promoter activities. Mass spectrometry, bioinformatics tools, genetic manipulation, and immunoblotting were used to identify the interacting proteins. Surprisingly, different fragments of NDRG1-OT1 had opposite effects on NDRG1. The first quarter fragment (1–149 nt) of NDRG1-OT1 had no effect on the NDRG1 promoter; the second quarter fragment (150–263 nt) repressed NDRG1 by increasing the binding affinity of HNRNPA1; the third quarter fragment (264–392 nt) improved NDRG1 promoter activity by recruiting HIF-1α; the fourth quarter fragment (393–508 nt) down-regulated NDRG1 promoter activity via down-regulation of KHSRP under hypoxia. In summary, we have found a novel mechanism by which different fragments of the same lncRNA can cause opposite effects within the same target gene.
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the hypoxia responsive lncrna ndrg ot1 promotes NDRG1 degradation via ubiquitin mediated proteolysis in breast cancer cells
Oncotarget, 2017Co-Authors: Hsinchen Lin, Ching-ching Yeh, Mong-hsun Tsai, Eric Y. Chuang, Loyun Chao, Hunghsin Chen, Liang-chuan LaiAbstract:Hypoxia can lead to solid tumor aggressiveness by driving multiple signaling pathways. Long non-coding RNAs respond to several extrinsic stimuli, causing changes in cancer cells by participating in multiple steps of gene expression. However, genomic profiling of long non-coding RNAs regulated by oxygen in breast cancer remained unclear. Therefore, the aims of this study were to identify oxygen-responsive long non-coding RNAs in breast cancer cells, and to delineate their regulatory mechanisms. The expression profiling of long non-coding RNAs in breast cancer cells growing under normoxic, hypoxic, and re-oxygenated conditions was examined using next-generation sequencing technology. Four hundred and seventy-two lncRNAs oxygen-responsive lncRNAs were identified. After examining the top three differentially expressed lncRNAs in hypoxia, we selected N-Myc Downstream Regulated Gene 1-Overlapping 1 (NDRG1-OT1) for further study, especially the most responsive isoform, NDRG1-OT1_v4. We overexpressed NDRG1-OT1_v4 under normoxia and performed microarray analysis to identify 108 NDRG1-OT1_v4 regulated genes and their functions. Among these genes, we found that both NDRG1 mRNA expression and NDRG1 protein levels were inhibited by NDRG1-OT1_v4. Finally, we used co-immunoprecipitation to show that NDRG1-OT1_v4 destabilizes NDRG1 by promoting ubiquitin-mediated proteolysis. Our findings reveal a new type of epigenetic regulation of NDRG1 by NDRG1-OT1_v4 in breast cancer cells.
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Abstract 975: Hypoxic long noncoding RNA NDRG1-OT1 inhibit NDRG1 in MCF-7 breast cancer cell line
Molecular and Cellular Biology Genetics, 2016Co-Authors: Hsinchen Lin, Mong-hsun Tsai, Liang-chuan Lai, Hunghsin Chen, Hsing-guang Chen, Mei-hung Chang, Eric Y. ChungAbstract:Hypoxia is a crucial factor that associated with solid tumor progression by driving multiple signaling pathway. Our lab previously reported that NDRG1 was oxygen-responsive genes and could affect cellular function in a breast cancer cell line MCF-7. Long-non coding RNAs (lncRNAs) have recently emerged as important regulators of tumor progression by participating in several process of gene expression. However, it is unclear whether lncRNAs are responsed to oxygen concentrations in breast cancer. Therefore, the aim of this study is to identify lncRNAs which are responsive upon changes in oxygen concentrations, and its regulatory mechanism in the breast cancer MCF-7 cells. We investigated the differentially expressed lncRNAs in different oxygen concentrations using next-generation sequencing (NGS) and validated these results through quantitative reverse transcription polymerase chain reaction (qRT-PCR). We found an lncRNA, NDRG1-OT1, that was up-regulated during hypoxia and down-regulated during reoxygenation. Next, we identified the differentially expressed genes regulated by NDRG1-OT1 using microarrays and confirmed these results through qRT-PCR and Western blotting. We found an oxygen responsive gene, NDRG1, was inhibited by NDRG1-OT1. Furthermore, Ingenuity Pathway Analysis(IPA) indicated that NDRG1-OT1 could involve in the Ubiquitin-proteasome pathway. We considered NDRG1-OT1 might regulate NDRG1 stability and ubiquitination, and we are proving these possibility by immunoblotting and immunoprecipitation. These findings may provide new insights into epigenetic regulation of breast cancer during hypoxia. Citation Format: Hsin-Chen Lin, Liang-Chuan Lai, Hsing-Guang Chen, Hung-Hsin Chen, Mei-Hung Chang, Mong-Hsun Tsai, Eric Y. Chung. Hypoxic long noncoding RNA NDRG1-OT1 inhibit NDRG1 in MCF-7 breast cancer cell line. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 975.
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Aryl Hydrocarbon Receptor Activates NDRG1 Transcription under Hypoxia in Breast Cancer Cells.
Scientific reports, 2016Co-Authors: Wei Yung Huang, Mong-hsun Tsai, Eric Y. Chuang, Loyun Chao, Ya Chu Chang, Qian Yu Kuok, Shih Ting Bai, Yuh Pyng Sher, Liang-chuan LaiAbstract:Hypoxia has been intensively investigated over the past several decades based on the observations that hypoxic tumors are more resistant to therapy and have a worse prognosis. Previously, we reported that N-myc downstream-regulated gene 1 (NDRG1) is strongly up-regulated under hypoxia and may play an important role in tumor adaptation to fluctuating oxygen concentrations. However, the regulatory mechanism of NDRG1 under hypoxia remains elusive. Therefore, the purpose of this study was to identify the transcription factors that regulate NDRG1 and to investigate the functional roles of NDRG1 in hypoxia. We showed that binding sites of aryl hydrocarbon receptor (AHR) were predicted in the NDRG1 promoter. Nuclear AHR was up-regulated in the presence of cobalt and hypoxia. AHR translocated to nuclei and bound between base pairs −412 and −388 of the NDRG1 promoter in hypoxia. Moreover, hypoxia-mimetic induction of NDRG1 was attenuated by knockdown of AHR expression. Also, overexpression of AHR facilitated cell proliferation and migration via up-regulation of NDRG1. These results showed for the first time that AHR positively regulates NDRG1 transcription through an AHR binding site by way of hypoxia-mimetic signaling, which may lead to development of a specific therapeutic regimen to prevent tumor malignancy under hypoxia.
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abstract 1983 aryl hydrocarbon receptor activates NDRG1 transcription under hypoxia in breast cancer cells
Cancer Research, 2015Co-Authors: Wei Yung Huang, Mong-hsun Tsai, Eric Y. Chuang, Liang-chuan LaiAbstract:Proceedings: AACR 106th Annual Meeting 2015; April 18-22, 2015; Philadelphia, PA Hypoxia has been intensively investigated over past decades based on the observations that hypoxic tumors were more resistant to therapy and had a worse prognosis. Previously, we reported that N-myc downstream-regulated gene 1 (NDRG1) was strongly up-regulated under hypoxia and may play an important role in tumor adaptation to fluctuation of oxygen concentrations. However, the regulatory mechanism of NDRG1 under hypoxia remains elusive. Therefore, the purpose of this study is to identify the novel transcription factors that regulate NDRG1 and to investigate the functional roles of NDRG1 in hypoxia. In silico analysis predicted binding sites of aryl hydrocarbon receptor (AHR) existing in the NDRG1 promoter. Western blotting showed that nuclear AHR was up-regulated in the presence of cobalt and hypoxia. Immunofluorescence staining and chromatin immunoprecipitation assays showed that AHR translocated to nuclei and bound to NDRG1 promoter in hypoxia. Luciferase reporter assays further showed that the binding site of AHR at -412 ∼ -388 bp played a crucial role in regulating NDRG1 under hypoxia-mimicking conditions. Moreover, hypoxia-mimetic induction of NDRG1 by was attenuated by knockdown of AHR expression using short interfering RNA. Also, overexpression of AHR facilitated cell proliferation and migration via up-regulation of NDRG1, whereas shRNA knockdown of NDRG1 reduced cell growth and motility. In summary, these results showed for the first time that AHR positively regulates NDRG1 transcription through a AHR binding site by hypoxia-mimetic signaling, which may lead to development of a specific therapeutic regime to prevent tumor malignancy under hypoxia. Citation Format: En-Yu Li, Wei-Yung Huang, Mong-Hsun Tsai, Eric Y. Chuang, Liang-Chuan Lai. Aryl hydrocarbon receptor activates NDRG1 transcription under hypoxia in breast cancer cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1983. doi:10.1158/1538-7445.AM2015-1983
Tiejun Zhang - One of the best experts on this subject based on the ideXlab platform.
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retinoic acid activated NDRG1a represses wnt β catenin signaling to allow xenopus pancreas oesophagus stomach and duodenum specification
PLOS ONE, 2013Co-Authors: Tiejun Zhang, Yonglong ChenAbstract:How cells integrate multiple patterning signals to achieve early endoderm regionalization remains largely unknown. Between gastrulation and neurulation, retinoic acid (RA) signaling is required, while Wnt/β-catenin signaling has to be repressed for the specification of the pancreas, oesophagus, stomach, and duodenum primordia in Xenopus embryos. In attempt to screen for RA regulated genes in Xenopus endoderm, we identified a direct RA target gene, N-myc downstream regulated gene 1a (NDRG1a) that showed expression early in the archenteron roof endoderm and late in the developing pancreas, oesophagus, stomach, and duodenum. Both antisense morpholino oligonucleotide mediated knockdown of NDRG1a in Xenopus laevis and the transcription activator-like effector nucleases (TALEN) mediated disruption of NDRG1 in Xenopus tropicalis demonstrate that like RA signaling, NDRG1a is specifically required for the specification of Xenopus pancreas, oesophagus, stomach, and duodenum primordia. Immunofluorescence data suggest that RA-activated NDRG1a suppresses Wnt/β-catenin signaling in Xenopus archenteron roof endoderm cells. Blocking Wnt/β-catenin signaling rescued NDRG1a knockdown phenotype. Furthermore, overexpression of the putative Wnt/β-catenin target gene Atf3 phenocopied knockdown of NDRG1a or inhibition of RA signaling, while Atf3 knockdown can rescue NDRG1a knockdown phenotype. Lastly, the pancreas/stomach/duodenum transcription factor Pdx1 was able to rescue Atf3 overexpression or NDRG1a knockdown phenotype. Together, we conclude that RA activated NDRG1a represses Wnt/β-catenin signaling to allow the specification of pancreas, oesophagus, stomach, and duodenum progenitor cells in Xenopus embryos.
