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Muniyandi A, Martin M, Sishtla K, Motolani A, Sun M, Jensen NR, Qi X, Boulton ME, Prabhu L, Lu T, Corson TW. PRMT5 is a therapeutic target in choroidal neovascularization. Sci Rep 2023; 13:1747. [PMID: 36720900 PMCID: PMC9889383 DOI: 10.1038/s41598-023-28215-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 01/16/2023] [Indexed: 02/02/2023] Open
Abstract
Ocular neovascular diseases including neovascular age-related macular degeneration (nvAMD) are widespread causes of blindness. Patients' non-responsiveness to currently used biologics that target vascular endothelial growth factor (VEGF) poses an unmet need for novel therapies. Here, we identify protein arginine methyltransferase 5 (PRMT5) as a novel therapeutic target for nvAMD. PRMT5 is a well-known epigenetic enzyme. We previously showed that PRMT5 methylates and activates a proangiogenic and proinflammatory transcription factor, the nuclear factor kappa B (NF-κB), which has a master role in tumor progression, notably in pancreatic ductal adenocarcinoma and colorectal cancer. We identified a potent and specific small molecule inhibitor of PRMT5, PR5-LL-CM01, that dampens the methylation and activation of NF-κB. Here for the first time, we assessed the antiangiogenic activity of PR5-LL-CM01 in ocular cells. Immunostaining of human nvAMD sections revealed that PRMT5 is highly expressed in the retinal pigment epithelium (RPE)/choroid where neovascularization occurs, while mouse eyes with laser induced choroidal neovascularization (L-CNV) showed PRMT5 is overexpressed in the retinal ganglion cell layer and in the RPE/choroid. Importantly, inhibition of PRMT5 by PR5-LL-CM01 or shRNA knockdown of PRMT5 in human retinal endothelial cells (HRECs) and induced pluripotent stem cell (iPSC)-derived choroidal endothelial cells (iCEC2) reduced NF-κB activity and the expression of its target genes, such as tumor necrosis factor α (TNF-α) and VEGF-A. In addition to inhibiting angiogenic properties of proliferation and tube formation, PR5-LL-CM01 blocked cell cycle progression at G1/S-phase in a dose-dependent manner in these cells. Thus, we provide the first evidence that inhibition of PRMT5 impedes angiogenesis in ocular endothelial cells, suggesting PRMT5 as a potential therapeutic target to ameliorate ocular neovascularization.
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Affiliation(s)
- Anbukkarasi Muniyandi
- Department of Ophthalmology, Eugene and Marilyn Glick Eye Institute, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Matthew Martin
- Department of Pharmacology & Toxicology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Kamakshi Sishtla
- Department of Ophthalmology, Eugene and Marilyn Glick Eye Institute, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Aishat Motolani
- Department of Pharmacology & Toxicology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Mengyao Sun
- Department of Pharmacology & Toxicology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Nathan R Jensen
- Department of Ophthalmology, Eugene and Marilyn Glick Eye Institute, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Xiaoping Qi
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL, 35233, USA
| | - Michael E Boulton
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL, 35233, USA
| | - Lakshmi Prabhu
- Department of Pharmacology & Toxicology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Tao Lu
- Department of Pharmacology & Toxicology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA.
- Department of Biochemistry & Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA.
- Department of Medical & Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, 46202, USA.
| | - Timothy W Corson
- Department of Ophthalmology, Eugene and Marilyn Glick Eye Institute, Indiana University School of Medicine, Indianapolis, IN, 46202, USA.
- Department of Pharmacology & Toxicology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA.
- Department of Biochemistry & Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA.
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2
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Prabhu L, Martin M, Chen L, Demir Ö, Jin J, Huang X, Motolani A, Sun M, Jiang G, Nakshatri H, Fishel ML, Sun S, Safa A, Amaro RE, Kelley MR, Liu Y, Zhang ZY, Lu T. Inhibition of PRMT5 by market drugs as a novel cancer therapeutic avenue. Genes Dis 2022; 10:267-283. [PMID: 37013054 PMCID: PMC10066340 DOI: 10.1016/j.gendis.2022.04.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 04/01/2022] [Accepted: 04/01/2022] [Indexed: 11/15/2022] Open
Abstract
Market drugs, such as Food and Drug Administration (FDA) or European Medicines Agency (EMA)-approved drugs for specific indications provide opportunities for repurposing for newer therapeutics. This potentially saves resources invested in clinical trials that verify drug safety and tolerance in humans prior to alternative indication approval. Protein arginine methyltransferase 5 (PRMT5) overexpression has been linked to promoting the tumor phenotype in several cancers, including pancreatic ductal adenocarcinoma (PDAC), colorectal cancer (CRC), and breast cancer (BC), making PRMT5 an important target for cancer therapy. Previously, we showed that PRMT5-mediated methylation of the nuclear factor (NF)-κB, partially contributes to its constitutive activation observed in cancers. In this study, we utilized an AlphaLISA-based high-throughput screening method adapted in our lab, and identified one FDA-approved drug, Candesartan cilexetil (Can, used in hypertension treatment) and one EMA-approved drug, Cloperastine hydrochloride (Clo, used in cough treatment) that had significant PRMT5-inhibitory activity, and their anti-tumor properties were validated using cancer phenotypic assays in vitro. Furthermore, PRMT5 selective inhibition of methyltransferase activity was confirmed by reduction of both NF-κB methylation and its subsequent activation upon drug treatment. Using in silico prediction, we identified critical residues on PRMT5 targeted by these drugs that may interfere with its enzymatic activity. Finally, Clo and Can treatment have exhibited marked reduction in tumor growth in vivo. Overall, we provide basis for pursuing repurposing Clo and Can as anti-PRMT5 cancer therapies. Our study offers potential safe and fast repurposing of previously unknown PRMT5 inhibitors into clinical practice.
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Affiliation(s)
- Lakshmi Prabhu
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Matthew Martin
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Lan Chen
- Chemical Genomics Core Facility, Indiana University School of Medicine, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Özlem Demir
- Department of Chemistry and Biochemistry, University of California, San Diego, CA 92093, USA
| | - Jiamin Jin
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Xiumei Huang
- Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Aishat Motolani
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Mengyao Sun
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Guanglong Jiang
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Harikrishna Nakshatri
- Department of Medicine, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Melissa L. Fishel
- Department of Pediatrics, Herman B Wells Center for Pediatric Research, Indianapolis, IN 46202, USA
- Indiana University Simon Comprehensive Cancer Center, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Steven Sun
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Ahmad Safa
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Rommie E. Amaro
- Department of Chemistry and Biochemistry, University of California, San Diego, CA 92093, USA
| | - Mark R. Kelley
- Department of Pediatrics, Herman B Wells Center for Pediatric Research, Indianapolis, IN 46202, USA
- Indiana University Simon Comprehensive Cancer Center, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Yunlong Liu
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Zhong-Yin Zhang
- Chemical Genomics Core Facility, Indiana University School of Medicine, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Tao Lu
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Indiana University Simon Comprehensive Cancer Center, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Corresponding author. Department of Pharmacology and Toxicology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA. Tel.: +(317) 278 0520; fax: +(317) 274 7714.
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Wei H, Hartley AV, Motolani A, Jiang G, Safa A, Prabhu L, Liu Y, Lu T. A complex signature network that controls the upregulation of PRMT5 in colorectal cancer. Genes Dis 2021; 9:285-287. [PMID: 35224144 PMCID: PMC8843984 DOI: 10.1016/j.gendis.2021.11.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 11/02/2021] [Accepted: 11/06/2021] [Indexed: 11/20/2022] Open
Affiliation(s)
- Han Wei
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA
| | - Antja-Voy Hartley
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA
| | - Aishat Motolani
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA
| | - Guanglong Jiang
- Department of Medical & Molecular Genetics, Indiana University School of Medicine, 975 W. Walnut Street, Indianapolis, IN 46202, USA
| | - Ahmad Safa
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA
| | - Lakshmi Prabhu
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA
| | - Yunlong Liu
- Department of Medical & Molecular Genetics, Indiana University School of Medicine, 975 W. Walnut Street, Indianapolis, IN 46202, USA
| | - Tao Lu
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA
- Department of Medical & Molecular Genetics, Indiana University School of Medicine, 975 W. Walnut Street, Indianapolis, IN 46202, USA
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA
- Corresponding author. Department of Pharmacology and Toxicology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA. Fax: +1 317 274 7714.
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Hartley AV, Wang B, Jiang G, Wei H, Sun M, Prabhu L, Martin M, Safa A, Sun S, Liu Y, Lu T. Regulation of a PRMT5/NF-κB Axis by Phosphorylation of PRMT5 at Serine 15 in Colorectal Cancer. Int J Mol Sci 2020; 21:ijms21103684. [PMID: 32456215 PMCID: PMC7279388 DOI: 10.3390/ijms21103684] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 05/19/2020] [Accepted: 05/20/2020] [Indexed: 12/19/2022] Open
Abstract
The overexpression of PRMT5 is highly correlated to poor clinical outcomes for colorectal cancer (CRC) patients. Importantly, our previous work demonstrated that PRMT5 overexpression could substantially augment activation of the nuclear factor kappa B (NF-κB) via methylation of arginine 30 (R30) on its p65 subunit, while knockdown of PRMT5 showed the opposite effect. However, the precise mechanisms governing this PRMT5/NF-κB axis are still largely unknown. Here, we report a novel finding that PRMT5 is phosphorylated on serine 15 (S15) in response to interleukin-1β (IL-1β) stimulation. Interestingly, we identified for the first time that the oncogenic kinase, PKCι could catalyze this phosphorylation event. Overexpression of the serine-to-alanine mutant of PRMT5 (S15A), in either HEK293 cells or CRC cells HT29, DLD1, and HCT116 attenuated NF-κB transactivation compared to WT-PRMT5, confirming that S15 phosphorylation is critical for the activation of NF-κB by PRMT5. Furthermore, the S15A mutant when compared to WT-PRMT5, could downregulate a subset of IL-1β-inducible NF-κB-target genes which correlated with attenuated promoter occupancy of p65 at its target genes. Additionally, the S15A mutant reduced IL-1β-induced methyltransferase activity of PRMT5 and disrupted the interaction of PRMT5 with p65. Furthermore, our data indicate that blockade of PKCι-regulated PRMT5-mediated activation of NF-κB was likely through phosphorylation of PRMT5 at S15. Finally, inhibition of PKCι or overexpression of the S15A mutant attenuated the growth, migratory, and colony-forming abilities of CRC cells compared to the WT-PRMT5. Collectively, we have identified a novel PKCι/PRMT5/NF-κB signaling axis, suggesting that pharmacological disruption of this pivotal axis could serve as the basis for new anti-cancer therapeutics.
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Affiliation(s)
- Antja-Voy Hartley
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA; (A.-V.H.); (H.W.); (M.S.); (L.P.); (M.M.); (A.S.); (S.S.)
| | - Benlian Wang
- Center for Proteomics and Bioinformatics, Case Western Reserve University, Cleveland, OH 44106, USA;
| | - Guanglong Jiang
- Department of Medical & Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN 46202, USA; (G.J.); (Y.L.)
| | - Han Wei
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA; (A.-V.H.); (H.W.); (M.S.); (L.P.); (M.M.); (A.S.); (S.S.)
| | - Mengyao Sun
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA; (A.-V.H.); (H.W.); (M.S.); (L.P.); (M.M.); (A.S.); (S.S.)
| | - Lakshmi Prabhu
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA; (A.-V.H.); (H.W.); (M.S.); (L.P.); (M.M.); (A.S.); (S.S.)
| | - Matthew Martin
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA; (A.-V.H.); (H.W.); (M.S.); (L.P.); (M.M.); (A.S.); (S.S.)
| | - Ahmad Safa
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA; (A.-V.H.); (H.W.); (M.S.); (L.P.); (M.M.); (A.S.); (S.S.)
| | - Steven Sun
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA; (A.-V.H.); (H.W.); (M.S.); (L.P.); (M.M.); (A.S.); (S.S.)
| | - Yunlong Liu
- Department of Medical & Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN 46202, USA; (G.J.); (Y.L.)
| | - Tao Lu
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA; (A.-V.H.); (H.W.); (M.S.); (L.P.); (M.M.); (A.S.); (S.S.)
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA
- Correspondence: ; Tel.: +1-(317)-278-0520; Fax: +1-(317)-274-7714
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Prabhu L, Chen L, Wei H, Demir Ö, Safa A, Zeng L, Amaro RE, O'Neil BH, Zhang ZY, Lu T. Development of an AlphaLISA high throughput technique to screen for small molecule inhibitors targeting protein arginine methyltransferases. Mol Biosyst 2018; 13:2509-2520. [PMID: 29099132 DOI: 10.1039/c7mb00391a] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The protein arginine methyltransferase (PRMT) family of enzymes comprises nine family members in mammals. They catalyze arginine methylation, either monomethylation or symmetric/asymmetric dimethylation of histone and non-histone proteins. PRMT methylation of its substrate proteins modulates cellular processes such as signal transduction, transcription, and mRNA splicing. Recent studies have linked overexpression of PRMT5, a member of the PRMT superfamily, to oncogenesis, making it a potential target for cancer therapy. In this study, we developed a highly sensitive (Z' score = 0.7) robotic high throughput screening (HTS) platform to discover small molecule inhibitors of PRMT5 by adapting the AlphaLISA™ technology. Using biotinylated histone H4 as a substrate, and S-adenosyl-l-methionine as a methyl donor, PRMT5 symmetrically dimethylated H4 at arginine (R) 3. Highly specific acceptor beads for symmetrically dimethylated H4R3 and streptavidin-coated donor beads bound the substrate, emitting a signal that is proportional to the methyltransferase activity. Using this powerful approach, we identified specific PRMT5 inhibitors P1608K04 and P1618J22, and further validated their efficacy and specificity for inhibiting PRMT5. Importantly, these two compounds exhibited much more potent efficacy than the commercial PRMT5 inhibitor EPZ015666 in both pancreatic and colorectal cancer cells. Overall, our work highlights a novel, powerful, and sensitive approach to identify specific PRMT5 inhibitors. The general principle of this HTS screening method can not only be applied to PRMT5 and the PRMT superfamily, but may also be extended to other epigenetic targets. This approach allows us to identify compounds that inhibit the activity of their respective targets, and screening hits like P1608K04 and P1618J22 may serve as the basis for novel drug development to treat cancer and/or other diseases.
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Affiliation(s)
- Lakshmi Prabhu
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA
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Prabhu L, Chen L, Safa A, Korc M, Zhang ZY, Lu T. Abstract 4862: Protein arginine methyltransferase 5 as a tumor promoter and therapeutic target in gastrointestinal cancers. Cancer Res 2018. [DOI: 10.1158/1538-7445.am2018-4862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Colorectal cancer (CRC) and pancreatic ductal adenocarcinoma (PDAC) are among the most commonly diagnosed forms of cancer in the United States. Due to their widespread prevalence and high mortality rate, it is vital to develop effective therapeutic drugs to combat these deadly diseases. In both CRC and PDAC, the multifunctional factor nuclear factor kappa B (NF-kB), a central coordinator of immune responses, is activated abnormally, leading to tumorigenesis and cancer progression. Therefore, controlling NF-kB activity is critical in the treatment of these cancers. Previously, we discovered a novel mechanism by which NF-kB is activated through methylation by an epigenetic enzyme known as protein arginine methyltransferase 5 (PRMT5). We showed that overexpression of PRMT5 significantly promoted several characteristics associated with cancer, including increased cell proliferation, migration, and anchorage-independent growth in both CRC and PDAC cells, thus, putting forward PRMT5 as a novel therapeutic target in these cancers. In this study, we successfully adapted AlphaLISA technique into a high-throughput screen platform, and further employed this approach to successfully identify PR5-LL-FDA1 as a potent PRMT5 inhibitor from commercially-available screening libraries. Furthermore, we confirmed that treatment of PDAC and CRC cells with PR5-LL-FDA1 led to decreased NF-kB activation, and reduced cancer associated properties in PDAC and CRC cells. Importantly, we show that PR5-LL-FDA1 is more efficacious than the commercial PRMT5 inhibitor, EPZ015666 in both PDAC and CRC. Our work clearly highlights the significant potential of PRMT5 as a therapeutic target in PDAC and CRC and hold the promise to establish PR5-LL-FDA1 as a promising basis for new drug development in the future.
Citation Format: Lakshmi Prabhu, Lan Chen, Ahmad Safa, Murray Korc, Zhong-Yin Zhang, Tao Lu. Protein arginine methyltransferase 5 as a tumor promoter and therapeutic target in gastrointestinal cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4862.
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Affiliation(s)
- Lakshmi Prabhu
- 1Indiana University School of Medicine, Indianapolis, IN
| | - Lan Chen
- 2Purdue University, West Lafayette, IN
| | - Ahmad Safa
- 1Indiana University School of Medicine, Indianapolis, IN
| | - Murray Korc
- 1Indiana University School of Medicine, Indianapolis, IN
| | | | - Tao Lu
- 1Indiana University School of Medicine, Indianapolis, IN
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Prabhu L, Wei H, Chen L, Demir Ö, Sandusky G, Sun E, Wang J, Mo J, Zeng L, Fishel M, Safa A, Amaro R, Korc M, Zhang ZY, Lu T. Adapting AlphaLISA high throughput screen to discover a novel small-molecule inhibitor targeting protein arginine methyltransferase 5 in pancreatic and colorectal cancers. Oncotarget 2018; 8:39963-39977. [PMID: 28591716 PMCID: PMC5522311 DOI: 10.18632/oncotarget.18102] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 04/28/2017] [Indexed: 12/14/2022] Open
Abstract
Pancreatic ductal adenocarcinoma (PDAC) and colorectal cancer (CRC) are notoriously challenging for treatment. Hyperactive nuclear factor κB (NF-κB) is a common culprit in both cancers. Previously, we discovered that protein arginine methyltransferase 5 (PRMT5) methylated and activated NF-κB. Here, we show that PRMT5 is highly expressed in PDAC and CRC. Overexpression of PRMT5 promoted cancer progression, while shRNA knockdown showed an opposite effect. Using an innovative AlphaLISA high throughput screen, we discovered a lead compound, PR5-LL-CM01, which exhibited robust tumor inhibition effects in both cancers. An in silico structure prediction suggested that PR5-LL-CM01 inhibits PRMT5 by binding with its active pocket. Importantly, PR5-LL-CM01 showed higher anti-tumor efficacy than the commercial PRMT5 inhibitor, EPZ015666, in both PDAC and CRC. This study clearly highlights the significant potential of PRMT5 as a therapeutic target in PDAC and CRC, and establishes PR5-LL-CM01 as a promising basis for new drug development in the future.
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Affiliation(s)
- Lakshmi Prabhu
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Han Wei
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Lan Chen
- Chemical Genomics Core Facility, Indiana University School of Medicine, Indianapolis, IN, USA.,Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, USA.,Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, USA
| | - Özlem Demir
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, USA
| | - George Sandusky
- Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Emily Sun
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - John Wang
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Jessica Mo
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Lifan Zeng
- Chemical Genomics Core Facility, Indiana University School of Medicine, Indianapolis, IN, USA.,Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Melissa Fishel
- Department of Pediatrics, Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Ahmad Safa
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Rommie Amaro
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, USA
| | - Murray Korc
- Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Zhong-Yin Zhang
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, USA.,Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, USA
| | - Tao Lu
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, USA.,Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, USA.,Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, USA
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8
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Martin M, Hua L, Wang B, Wei H, Prabhu L, Hartley AV, Jiang G, Liu Y, Lu T. Novel Serine 176 Phosphorylation of YBX1 Activates NF-κB in Colon Cancer. J Biol Chem 2017; 292:3433-3444. [PMID: 28077578 DOI: 10.1074/jbc.m116.740258] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Revised: 01/09/2017] [Indexed: 12/22/2022] Open
Abstract
Y box protein 1 (YBX1) is a well known oncoprotein that has tumor-promoting functions. YBX1 is widely considered to be an attractive therapeutic target in cancer. To develop novel therapeutics to target YBX1, it is of great importance to understand how YBX1 is finely regulated in cancer. Previously, we have shown that YBX1 could function as a tumor promoter through phosphorylation of its Ser-165 residue, leading to the activation of the NF-κB signaling pathway (1). In this study, using mass spectrometry analysis, we discovered a distinct phosphorylation site, Ser-176, on YBX1. Overexpression of the YBX1-S176A (serine-to-alanine) mutant in either HEK293 cells or colon cancer HT29 cells showed dramatically reduced NF-κB-activating ability compared with that of WT-YBX1, confirming that Ser-176 phosphorylation is critical for the activation of NF-κB by YBX1. Importantly, the mutant of Ser-176 and the previously reported Ser-165 sites regulate distinct groups of NF-κB target genes, suggesting the unique and irreplaceable function of each of these two phosphorylated serine residues. Our important findings could provide a novel cancer therapy strategy by blocking either Ser-176 or Ser-165 phosphorylation or both of YBX1 in colon cancer.
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Affiliation(s)
| | | | - Benlian Wang
- Center for Proteomics and Bioinformatics, Case Western Reserve University, Cleveland, Ohio 44106
| | - Han Wei
- Departments of Pharmacology and Toxicology
| | | | | | - Guanglong Jiang
- Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Yunlong Liu
- Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Tao Lu
- Departments of Pharmacology and Toxicology; Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana 46202; Biochemistry and Molecular Biology.
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Prabhu L, Srinivas J. Performance Evaluation of Two Meta-heuristic Schemes in Airfoil Design. Arab J Sci Eng 2016. [DOI: 10.1007/s13369-016-2102-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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10
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Prabhu L, Mundade R, Wang B, Wei H, Hartley AV, Martin M, McElyea K, Temm CJ, Sandusky G, Liu Y, Lu T. Critical role of phosphorylation of serine 165 of YBX1 on the activation of NF-κB in colon cancer. Oncotarget 2016; 6:29396-412. [PMID: 26318844 PMCID: PMC4745735 DOI: 10.18632/oncotarget.5120] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Accepted: 07/24/2015] [Indexed: 11/25/2022] Open
Abstract
Y-box binding protein 1 [YBX1] is a multifunctional protein known to facilitate many of the hallmarks of cancer. Elevated levels of YBX1 protein are highly correlated with cancer progression, making it an excellent marker in cancer. The connection between YBX1 and the important nuclear factor κB [NF-κB] has never been reported. Here, we show that overexpression of wild type YBX1 [WT-YBX1] activates NF-κB, suggesting that YBX1 is a potential NF-κB activator. Furthermore, using mass spectrometry analysis we identified novel phosphorylation of serine 165 [S165] on YBX1. Overexpression of the S165A-YBX1 mutant in either HEK293 cells or colon cancer HT29 cells showed dramatically reduced NF-κB activating ability as compared with that of WT-YBX1, confirming that S165 phosphorylation is critical for the activation of NF-κB by YBX1. We also show that expression of the S165A-YBX1 mutant dramatically decreased the expression of NF-κB-inducible genes, reduced cell growth, and compromised tumorigenic ability as compared with WT-YBX1. Taken together, we provide the first evidence that YBX1 functions as a tumor promoter via NF-κB activation, and phosphorylation of S165 of YBX1 is critical for this function. Therefore, our important discovery may lead to blocking S165 phosphorylation as a potential therapeutic strategy to treat colon cancer.
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Affiliation(s)
- Lakshmi Prabhu
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Rasika Mundade
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Benlian Wang
- Center for Proteomics and Bioinformatics, Case Western Reserve University, Cleveland, Ohio, USA
| | - Han Wei
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Antja-Voy Hartley
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Matthew Martin
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Kyle McElyea
- Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Constance J Temm
- Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN, USA
| | - George Sandusky
- Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Yunlong Liu
- Department of Medical and Molecular Genetics, Medical Research and Library Building, Indianapolis, IN, USA.,Center for Computational Biology and Bioinformatics, Health Information and Translational Sciences, Indianapolis, IN, USA
| | - Tao Lu
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, USA.,Department of Medical and Molecular Genetics, Medical Research and Library Building, Indianapolis, IN, USA.,Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, USA
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11
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Abstract
Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest cancers, and in spite of intense efforts there are limited therapeutic options for patients with PDAC. PDACs harbor a high frequency of Kras mutations and other driver mutations that lead to altered signaling pathways and contribute to therapeutic resistance. Importantly, constitutive activation of nuclear factor κB (NF-κB) is frequently observed in PDAC. An increasing body of evidence suggests that both classical and non-classical NF-κB pathways play a crucial role in PDAC development and progression. In this review, we update the most recent advances regarding different aspects of NF-κB involvement in PDAC development and progression, emphasizing its potential as a therapeutic target and the need to discover pathway-specific cytosolic NF-κB regulators which could be used to design novel therapeutic strategies for PDAC.
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Affiliation(s)
- Lakshmi Prabhu
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN USA
| | - Rasika Mundade
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN USA
| | - Murray Korc
- Department of Medicine, Indiana University School of Medicine, Indianapolis, IN USA. Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN USA
| | - Patrick J Loehrer
- Division of Hematology and Oncology, Indiana Cancer Pavilion, Indianapolis, IN USA
| | - Tao Lu
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN USA. Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN USA. Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN USA
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12
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Mundade R, Ozer HG, Wei H, Prabhu L, Lu T. Role of ChIP-seq in the discovery of transcription factor binding sites, differential gene regulation mechanism, epigenetic marks and beyond. Cell Cycle 2015; 13:2847-52. [PMID: 25486472 PMCID: PMC4614920 DOI: 10.4161/15384101.2014.949201] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Many biologically significant processes, such as cell differentiation and cell cycle progression, gene transcription and DNA replication, chromosome stability and epigenetic silencing etc. depend on the crucial interactions between cellular proteins and DNA. Chromatin immunoprecipitation (ChIP) is an important experimental technique for studying interactions between specific proteins and DNA in the cell and determining their localization on a specific genomic locus. In recent years, the combination of ChIP with second generation DNA-sequencing technology (ChIP-seq) allows precise genomic functional assay. This review addresses the important applications of ChIP-seq with an emphasis on its role in genome-wide mapping of transcription factor binding sites, the revelation of underlying molecular mechanisms of differential gene regulation that are governed by specific transcription factors, and the identification of epigenetic marks. Furthermore, we also describe the ChIP-seq data analysis workflow and a perspective for the exciting potential advancement of ChIP-seq technology in the future.
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Affiliation(s)
- Rasika Mundade
- a Department of Pharmacology and Toxicology ; Indiana University School of Medicine ; Indianapolis , IN USA
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13
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Wang B, Wei H, Prabhu L, Zhao W, Martin M, Hartley AV, Lu T. Role of Novel Serine 316 Phosphorylation of the p65 Subunit of NF-κB in Differential Gene Regulation. J Biol Chem 2015; 290:20336-47. [PMID: 26082493 DOI: 10.1074/jbc.m115.639849] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Indexed: 01/08/2023] Open
Abstract
Nuclear factor κB (NF-κB) is a central coordinator in immune and inflammatory responses. Constitutive NF-κB is often found in some types of cancers, contributing to oncogenesis and tumor progression. Therefore, knowing how NF-κB is regulated is important for its therapeutic control. Post-translational modification of the p65 subunit of NF-κB is a well known approach for its regulation. Here, we reported that in response to interleukin 1β, the p65 subunit of NF-κB is phosphorylated on the novel serine 316. Overexpression of S316A (serine 316 → alanine) mutant exhibited significantly reduced ability to activate NF-κB and decreased cell growth as compared with wtp65 (wild type p65). Moreover, conditioned media from cells expressing the S316A-p65 mutant had a considerably lower ability to induce NF-κB than that of wtp65. Our data suggested that phosphorylation of p65 on Ser-316 controls the activity and function of NF-κB. Importantly, we found that phosphorylation at the novel Ser-316 site and other two known phosphorylation sites, Ser-529 and Ser-536, either individually or cooperatively, regulated distinct groups of NF-κB-dependent genes, suggesting the unique role of each individual phosphorylation site on NF-κB-dependent gene regulation. Our novel findings provide an important piece of evidence regarding differential regulation of NF-κB-dependent genes through phosphorylation of different p65 serine residues, thus shedding light on novel mechanisms for the pathway-specific control of NF-κB. This knowledge is key to develop strategies for prevention and treatment of constitutive NF-κB-driven inflammatory diseases and cancers.
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Affiliation(s)
- Benlian Wang
- From the Center for Proteomics and Bioinformatics, Case Western Reserve University, Cleveland, Ohio 44106
| | - Han Wei
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Lakshmi Prabhu
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Wei Zhao
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202, and
| | - Matthew Martin
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Antja-Voy Hartley
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Tao Lu
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, Indiana 46202, Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202, and Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana 46202
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14
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Prabhu L, Hartley AV, Martin M, Warsame F, Sun E, Lu T. Role of post-translational modification of the Y box binding protein 1 in human cancers. Genes Dis 2015; 2:240-246. [PMID: 30258867 PMCID: PMC6150071 DOI: 10.1016/j.gendis.2015.05.001] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2015] [Accepted: 05/12/2015] [Indexed: 12/21/2022] Open
Abstract
Y box binding protein-1 (YBX1) belongs to a DNA- and RNA-binding family of transcription factors, containing the highly conserved cold shock domain (CSD). YBX1 is involved in a number of cellular functions including transcription, translation, DNA damage repair etc., and it is upregulated during times of environmental stress. YBX1 is localized in both the cytoplasm and the nucleus. There, its nuclear translocation is observed in a number of cancers and is associated with poor prognosis and disease progression. Additionally, YBX1 expression is upregulated in a variety of cancers, pointing towards its role as a potential oncogene. Under certain circumstances, YBX1 also promotes the expression of multidrug resistance 1 (MDR1) gene, which is involved in the development of drug resistance. Thus, it is critical to understand the mechanism of YBX1 regulation and its downstream effects on promoting cancer development. A number of recent studies have highlighted the mechanisms of YBX1 regulation. Mass spectrometric analyses have reported several post-translational modifications that possibly play an important role in modulating YBX1 function. Phosphorylation is the most widely occurring post-translational modification in YBX1. In vivo analyses of sites like S102 and more recently, S165 illustrate the relationship of post-translational regulation of YBX1 in promoting cell proliferation and tumor growth. This review provides a comprehensive and up-to-date account of post-translational modifications identified in YBX1. This knowledge is a key in allowing us to better understand the mechanism of YBX1 regulation, which will aid in development of novel therapeutic strategies to target YBX1 in many types of cancer in the future.
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Affiliation(s)
- Lakshmi Prabhu
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA
| | - Antja-Voy Hartley
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA
| | - Matthew Martin
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA
| | - Fadumo Warsame
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA
| | - Emily Sun
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA
| | - Tao Lu
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA.,Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA.,Department of Medical and Molecular Genetics, 975 West Walnut Street, Medical Research and Library Building, Indianapolis, IN 46202, USA
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15
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Mundade R, Imperiale TF, Prabhu L, Loehrer PJ, Lu T. Genetic pathways, prevention, and treatment of sporadic colorectal cancer. Oncoscience 2014; 1:400-6. [PMID: 25594038 PMCID: PMC4284625 DOI: 10.18632/oncoscience.59] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2014] [Accepted: 06/28/2014] [Indexed: 12/16/2022] Open
Abstract
Epithelial cancer of the colon and rectum, also known as colorectal cancer (CRC), results from a progressive accumulation of genetic and epigenetic alterations that lead to uncontrolled growth of colonocytes, the cells lining the colon and rectum. CRC is the second leading cause of cancer-related deaths and the third most common cancer in men and in women in the U.S. Of all the patients diagnosed with CRC every year, it is estimated that the vast majority of CRCs are non-hereditary “sporadic cancers” with no apparent evidence of an inherited component. Sporadic CRC results from the cumulative effects of multiple genetic and epigenetic alterations caused by somatic mutations, which may themselves be the indirect result of several environmental factors. This review examines our current understanding of the major genetic alterations leading to colon cancer, options for prevention and early detection of CRC, and the currently available treatment approaches that may target these different genetic alterations.
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Affiliation(s)
- Rasika Mundade
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN USA
| | - Thomas F Imperiale
- Division of Gastroenterology and Hepatology, Regenstrief Health Center, Roudebush VA Medical Center, Indianapolis, IN USA
| | - Lakshmi Prabhu
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN USA
| | - Patrick J Loehrer
- Division of Hematology and Oncology, Indiana Cancer Pavilion, Indianapolis, IN USA
| | - Tao Lu
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN USA ; Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN USA
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16
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Liu B, Dou CL, Prabhu L, Lai E. FAST-2 is a mammalian winged-helix protein which mediates transforming growth factor beta signals. Mol Cell Biol 1999; 19:424-30. [PMID: 9858566 PMCID: PMC83900 DOI: 10.1128/mcb.19.1.424] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/1998] [Accepted: 10/14/1998] [Indexed: 11/20/2022] Open
Abstract
The mechanisms by which transforming growth factor beta (TGF-beta) and related ligands regulate transcription remain poorly understood. The winged-helix (WH) transcription factor fork head activin signal transducer 1 (FAST-1) was identified as a mediator of activin signaling in Xenopus embryos (X. Chen, M. J. Rubock, and M. Whitman, Nature 383:691-696, 1996). We have cloned a novel WH gene from the mouse which shares many properties with FAST-1. We find that this gene, which we call FAST-2, is able to mediate transcriptional activation by TGF-beta. FAST-2 also interacts directly with Smad2, a cytoplasmic protein which is translocated to the nucleus in response to TGF-beta, and forms a multimeric complex with Smad2 and Smad4 on the activin response element, a high-affinity binding site for FAST-1. Analysis of the sequences of FAST-1 and FAST-2 reveals substantial protein sequence divergence compared to known vertebrate orthologs in the WH family. This suggests that FAST-2 represents a new WH gene related to FAST-1, which functions to mediate TGF-beta signals in mammals. We have also examined the structure of the FAST-2 gene and find that it overlaps with a kinesin motor protein gene. The genes are transcribed in opposite orientations, and their transcripts overlap in the 3' untranslated region.
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Affiliation(s)
- B Liu
- Cell Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York, USA
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17
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Sultana S, Nirodi CS, Ram N, Prabhu L, Padmanaban G. A 65-kDa protein mediates the positive role of heme in regulating the transcription of CYP2B1/B2 gene in rat liver. J Biol Chem 1997; 272:8895-900. [PMID: 9083008 DOI: 10.1074/jbc.272.14.8895] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Heme deficiency precipitated by CoCl2 administration to rats leads to a striking decrease in the inducibility of CYP2B1/B2 mRNA levels and its transcription by phenobarbitone (PB), besides decreasing the basal levels. Exogenous hemin administration counteracts the effects of CoCl2 administration. The binding of nuclear proteins to labeled positive cis-acting element (-69 to -98 nucleotides) in the near 5'-upstream region of the gene is inhibited by CoCl2 administration to saline or PB-treated rats, as assessed in gel shift assays. Administration of exogenous hemin to the animal or addition in vitro to the extracts is able to overcome the effects of CoCl2 treatment. The protein mediating this effect has been purified from CoCl2 administered nuclear extracts by heparin-agarose, positive element oligonucleotide affinity, and heme affinity column chromatography. This 65-kDa protein manifests very little binding to the positive element, but in the presence of certain other nuclear proteins, shows a strong heme-responsive binding. The purified protein binds heme. It is also able to stimulate transcription of a minigene construct of the CYP2B1/B2 gene containing -179 nucleotides of the 5'-upstream region and the I exon in a cell-free system, manifesting heme response. It is concluded that the 65-kDa protein mediates the constitutive requirement of heme for the transcription of CYP2B1/B2 gene.
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Affiliation(s)
- S Sultana
- Department of Biochemistry, Indian Institute of Science, Bangalore, 560 012 India
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18
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Nirodi CS, Sultana S, Ram N, Prabhu L, Padmanaban G. Involvement of synthesis and phosphorylation of nuclear protein factors that bind to the positive cis-acting element in the transcriptional activation of the CYP2B1/B2 gene by phenobarbitone in vivo. Arch Biochem Biophys 1996; 331:79-86. [PMID: 8660686 DOI: 10.1006/abbi.1996.0285] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The synthesis and phosphorylation of protein factor(s) that bind to the positive cis-acting element (-69 to -98 nt) of the CYP2B1/B2 gene have been examined in vivo in the rat. Treatment of rats with cycloheximide, a protein synthetic inhibitor, suppresses basal as well as phenobarbitone-induced levels of CYP2B1/B2 mRNA and its run-on transcription. Under these conditions, complex formation of the nuclear extract with the positive element is also inhibited, as judged by gel shift assays. Treatment of rats with 2-aminopurine, a general protein kinase inhibitor, blocks the phenobarbitone-mediated increase in CYP2B1/B2 mRNA, cell-free transcription of a minigene construct containing the positive element, pP450e179DNA, and binding of nuclear proteins to the positive element. Treatment of rats with okadaic acid, a protein phosphatase inhibitor, mimics the effects of phenobarbitone, but only partially. Thus, both phenobarbitone and okadaic acid individually enhance binding of the nuclear protein(s) to the positive element, cell-free transcription of the minigene construct, and phosphorylation of the approximately 26- and 94-kDa proteins binding to the positive element. But unlike phenobarbitone, okadaic acid is not an inducer of CYP2B1/B2 mRNA or its run-on transcription. Thus, phenobarbitone-responsive positive element interactions constitute only a minimal requirement, and okadaic acid is perhaps not able to bring about the total requirement for activation of CYP2B1/B2 gene transcription that should include interaction between the minimal promoter and further upstream elements. An intriguing feature is the antagonistic effect of okadaic acid on phenobarbitone-mediated effects on CYP21B1/B2 mRNA levels, cell-free and run-on transcription, and nuclear protein binding to the positive element. The reason for this antagonism is not clear. It is concluded that phenobarbitone treatment enhances in vivo the synthesis and phosphorylation of protein factors binding to the positive element and these constitute a minimal requirement for the transcriptional activation of the CYP2B1/B2 gene.
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Affiliation(s)
- C S Nirodi
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
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19
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Prabhu L, Upadhya P, Ram N, Nirodi CS, Sultana S, Vatsala PG, Mani SA, Rangarajan PN, Surolia A, Padmanaban G. A model for the transcriptional regulation of the CYP2B1/B2 gene in rat liver. Proc Natl Acad Sci U S A 1995; 92:9628-32. [PMID: 7568186 PMCID: PMC40855 DOI: 10.1073/pnas.92.21.9628] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The phenobarbitone-responsive minimal promoter has been shown to lie between nt -179 and nt + 1 in the 5' (upstream) region of the CYP2B1/B2 gene in rat liver, on the basis of the drug responsiveness of the sequence linked to human growth hormone gene as reporter and targeted to liver as an asialoglycoprotein-DNA complex in vivo. Competition analyses of the nuclear protein-DNA complexes formed in gel shift assays with the positive (nt -69 to -98) and negative (nt -126 to -160) cis elements (PE and NE, respectively) identified within this region earlier indicate that the same protein may be binding to both the elements. The protein species purified on PE and NE affinity columns appear to be identical based on SDS/PAGE analysis, where it migrates as a protein of 26-28 kDa. Traces of a high molecular weight protein (94-100 kDa) are also seen in the preparation obtained after one round of affinity chromatography. The purified protein stimulates transcription of a minigene construct containing the 179 nt on the 5' side of the CYP2B1/B2 gene linked to the I exon in a cell-free system from liver nuclei. The purified protein can give rise to all the three complexes (I, II, and III) with the PE, just as the crude nuclear extract, under appropriate conditions. Manipulations in vitro indicate that the NE has a significantly higher affinity for the dephosphorylated form than for the phosphorylated form of the protein. The PE binds both forms. Phenobarbitone treatment of the animal leads to a significant increase in the phosphorylation of the 26- to 28-kDa and 94-kDa proteins in nuclear labeling experiments followed by isolation on a PE affinity column. We propose that the protein binding predominantly to the NE in the dephosphorylated state characterizes the basal level of transcription of the CYP2B1/B2 gene. Phenobarbitone treatment leads to phosphorylation of the protein, shifting the equilibrium toward binding to the PE. This can promote interaction with an upstream enhancer through other proteins such as the 94-kDa protein and leads to a significant activation of transcription.
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Affiliation(s)
- L Prabhu
- Department of Biochemistry, Indian Institute of Science, Bangalore
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20
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Ram N, Rao MV, Prabhu L, Nirodi CS, Sultana S, Vatsala PG, Padmanaban G. Characterization of a negative cis-acting DNA element regulating the transcription of CYP2B1/B2 gene in rat liver. Arch Biochem Biophys 1995; 317:39-45. [PMID: 7872801 DOI: 10.1006/abbi.1995.1133] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The region -160 to -127 nt of the upstream of CYP2B1/B2 gene has been found to function as a negative cis-acting element on the basis of DNase-I footprint and gel mobility shift assays as well as cell-free transcriptional assays using Bal-31 mutants. A reciprocal relationship in the interaction of the negative and the recently characterized positive elements with their respective protein factors has been found under repressed and induced conditions of the gene. The negative element also harbors the core glucocorticoid responsive sequence, TGTCCT. It is concluded that the negative element mediates the repressed state of the gene under the uninduced condition and also mediates the repressive effect of dexamethasone, when given along with the inducer phenobarbitone in rats. Dexamethasone is able to antagonize the effects of phenobarbitone at as low a concentration as 100 micrograms/kg body wt in these animals.
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Affiliation(s)
- N Ram
- Department of Biochemistry, Indian Institute of Science, Bangalore
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21
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Daga SR, Prabhu L, Pol PP, Shah H. Neonatal stroke. Indian Pediatr 1985; 22:923-4. [PMID: 3837780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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