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Mouawad R, Neamati N. Inhibition of Protein Disulfide Isomerase (PDIA1) Leads to Proteasome-Mediated Degradation of Ubiquitin-like PHD and RING Finger Domain-Containing Protein 1 (UHRF1) and Increased Sensitivity of Glioblastoma Cells to Topoisomerase II Inhibitors. ACS Pharmacol Transl Sci 2022; 6:100-114. [PMID: 36654750 PMCID: PMC9841782 DOI: 10.1021/acsptsci.2c00186] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Indexed: 12/12/2022]
Abstract
Glioblastoma (GBM) is the most aggressive brain tumor, and the prognosis remains poor with current available treatments. PDIA1 is considered a promising therapeutic target in GBM. In this study, we demonstrate that targeting PDIA1 results in increased GBM cell death by topoisomerase II (Top-II) inhibitors resulting in proteasome-mediated degradation of the oncogenic protein UHRF1. Combination of the PDIA1 inhibitor, bepristat-2a, produces strong synergy with doxorubicin, etoposide, and mitoxantrone in GBM and other cancer cell lines. Our bioinformatics analysis of multiple datasets revealed downregulation of UHRF1, upon PDIA1 inhibition. In addition, PDIA1 inhibition results in proteasome-mediated degradation of UHRF1 protein. Interestingly, treatment of GBM cells with bepristat-2a results in increased apoptosis and resistance to ferroptosis. Our findings emphasize the importance of PDIA1 as a therapeutic target in GBM and present a promising new therapeutic approach using Top-II inhibitors for GBM treatment.
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Hui B, Pan S, Che S, Sun Y, Yan Y, Guo J, Gong T, Ren J, Zhang X. Silencing UHRF1 Enhances Radiosensitivity of Esophageal Squamous Cell Carcinoma by Inhibiting the PI3K/Akt/mTOR Signaling Pathway. Cancer Manag Res 2021; 13:4841-4852. [PMID: 34188537 PMCID: PMC8232844 DOI: 10.2147/cmar.s311192] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 04/29/2021] [Indexed: 12/24/2022] Open
Abstract
Purpose Resistance to radiotherapy results in a high treatment failure rate for locally advanced esophageal squamous cell carcinoma (ESCC). Ubiquitin-like with plant homeodomain and ring-finger domains 1 (UHRF1), is associated with poor prognosis in ESCC. The present study aims to characterize the effect of UHRF1 silencing on the radiosensitivity of ESCC and its potential mechanism. Methods Both in vitro and in vivo experiments were conducted to observe the effects of UHRF1 silencing on the radiosensitivity of ESCC. The effects of UHRF1 silencing on the apoptosis of ESCC cells were assessed by flow cytometry. The expression of apoptosis-related factors (caspase-3 and Bcl-2), PI3K/Akt/mTOR signaling pathway-related factors (PTEN, p-Akt and Akt, p-mTOR and mTOR), and DNMT1 were measured via Western blot, and the status of PTEN methylation was detected by methylation-specific PCR. Immunohistochemistry was used to detect the expressions of PTEN, p-AKT, and p-mTOR in xenograft tumor tissues. Results In vitro and in vivo experiments showed that UHRF1 knock-down inhibited ESCC cell growth and enhanced their radiosensitivity. shUHRF1 combined with radiation significantly increased ESCC cell apoptosis. Meanwhile, it activated the expression of caspase-3 and inhibited the expression of Bcl-2. shUHRF1 inhibited the expression of DNMT1 and reduced the methylation of PTEN, and then upregulated the expression of PTEN to inhibit the PI3K/Akt/mTOR signaling pathway. On the contrary, the PI3K/Akt/mTOR signaling pathway can be activated by upregulation of UHRF1. Conclusion Our findings provide a theoretical basis for UHRF1 as a target to improve the radiosensitivity of ESCC.
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Affiliation(s)
- Beina Hui
- Department of Radiation Oncology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi Province, 710061, People's Republic of China
| | - Shupei Pan
- Department of Radiation Oncology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi Province, 710004, People's Republic of China
| | - Shaomin Che
- Department of Radiation Oncology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi Province, 710061, People's Republic of China
| | - Yuchen Sun
- Department of Radiation Oncology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi Province, 710061, People's Republic of China
| | - Yanli Yan
- Department of Radiation Oncology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi Province, 710061, People's Republic of China
| | - Jia Guo
- Department of Radiation Oncology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi Province, 710061, People's Republic of China
| | - Tuotuo Gong
- Department of Radiation Oncology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi Province, 710061, People's Republic of China
| | - Juan Ren
- Department of Radiation Oncology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi Province, 710061, People's Republic of China
| | - Xiaozhi Zhang
- Department of Radiation Oncology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi Province, 710061, People's Republic of China
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Polepalli S, George SM, Valli Sri Vidya R, Rodrigues GS, Ramachandra L, Chandrashekar R, M DN, Rao PP, Pestell RG, Rao M. Role of UHRF1 in malignancy and its function as a therapeutic target for molecular docking towards the SRA domain. Int J Biochem Cell Biol 2019; 114:105558. [DOI: 10.1016/j.biocel.2019.06.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Revised: 05/30/2019] [Accepted: 06/14/2019] [Indexed: 01/07/2023]
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Bu X, Zhang J, Tian F, Wang X, Wu L, Tian W. Value of Diffusion-Weighted Magnetic Resonance Imaging Combined with miR-18a Level in Predicting Radiosensitivity of Cervical Cancer. Med Sci Monit 2018; 24:7271-7278. [PMID: 30308669 PMCID: PMC6194752 DOI: 10.12659/msm.910990] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Background Radioresistance during radiotherapy of cervical cancer often leads to treatment failure; therefore, there is an urgent need to develop effective predictive indicators of radiosensitivity for cervical cancer patients. Material/Methods Cervical cancer cells were collected from 40 patients who received surgical resections. The relationships between apparent diffusion coefficient (ADC) values of masses before surgery and different micro-RNAs (miRNA) levels (miR-18a, miR-132, and miR-145) of these cells were investigated. Cervical cancer cells were divided into 4 groups according to the ADC values of original tumor tissues and expression level of miR-18a. Then, these cells were exposed with irradiation both in vitro and in vivo. Results Advanced cervical cancer showed lower ADC values in magnetic resonance imaging. miR-18a, miR-132, and miR-145 all were increased in the cervical cancer tissues, while miR-18a showed a more marked negative correlation with ADC values. The results of in vitro and in vivo assays showed that higher expression of miR-18a in cervical cancer cells leads to more radiosensitivity, especially in cells from cancer tissues with lower ADC values. Conclusions The combination of ADC values with expression level of miR-18a may be a new and reliable predictor for radiosensitivity of cervical cancer, helping cervical cancer patients with low ADC values and high expressions of miR-18a to achieve better outcomes in radiotherapy.
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Affiliation(s)
- Xinhua Bu
- Department of Gynecology and Obstetrics, Taizhou People's Hospital, Taizhou, Jiangsu, China (mainland)
| | - Ji Zhang
- Department of Radiology, Taizhou People's Hospital, Taizhou, Jiangsu, China (mainland)
| | - Fangzheng Tian
- Department of Radiology, Taizhou People's Hospital, Taizhou, Jiangsu, China (mainland)
| | - Xiulan Wang
- Department of Radiology, Taizhou People's Hospital, Taizhou, Jiangsu, China (mainland)
| | - Linyun Wu
- Taizhou Polytechnic College, Taizhou, Jiangsu, China (mainland)
| | - Weizhong Tian
- Department of Radiology, Taizhou People's Hospital, Taizhou, Jiangsu, China (mainland)
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Patnaik D, Estève PO, Pradhan S. Targeting the SET and RING-associated (SRA) domain of ubiquitin-like, PHD and ring finger-containing 1 (UHRF1) for anti-cancer drug development. Oncotarget 2018; 9:26243-26258. [PMID: 29899856 PMCID: PMC5995235 DOI: 10.18632/oncotarget.25425] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 05/02/2018] [Indexed: 12/19/2022] Open
Abstract
Ubiquitin-like containing PHD Ring Finger 1 (UHRF1) is a multi-domain protein with a methyl-DNA binding SRA (SET and RING-associated) domain, required for maintenance DNA methylation mediated by DNMT1. Primarily expressed in proliferating cells, UHRF1 is a cell-cycle regulated protein that is required for S phase entry. Furthermore, UHRF1 participates in transcriptional gene regulation by connecting DNA methylation to histone modifications. Upregulation of UHRF1 may serve as a biomarker for a variety of cancers; including breast, gastric, prostate, lung and colorectal carcinoma. To this end, overexpression of UHRF1 promotes cancer metastasis by triggering aberrant patterns of DNA methylation, and subsequently, silencing tumor suppressor genes. Various small molecule effectors of UHRF1 have been reported in the literature, although the mechanism of action may not be fully characterized. Small molecules that potentially bind to the SRA domain may affect the ability of UHRF1 to bind hemimethylated DNA; thereby reducing aberrant DNA methylation. Therefore, in a subset of cancers, small molecule UHRF1 inhibitors may restore normal gene expression and serve as useful anti-cancer therapeutics.
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UHRF1 depletion sensitizes retinoblastoma cells to chemotherapeutic drugs via downregulation of XRCC4. Cell Death Dis 2018; 9:164. [PMID: 29415984 PMCID: PMC5833858 DOI: 10.1038/s41419-017-0203-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 12/05/2017] [Accepted: 12/06/2017] [Indexed: 12/19/2022]
Abstract
UHRF1 (ubiquitin-like with PHD and ring finger domains 1) is highly expressed in various human cancers including retinoblastoma, and associated with tumor-promoting effects such as inhibition of apoptosis and high proliferation. However, the molecular mechanisms underlying tumor-promoting functions of UHRF1 in retinoblastoma still remain elusive. Here, we show that stable knockdown of UHRF1 renders retinoblastoma cells sensitized to conventional chemotherapeutic drugs such as etoposide and camptothecin, resulting in enhanced DNA damage and apoptotic cell death. We found that UHRF1-depleted retinoblastoma cells can recognize DNA damages normally but have markedly low expression of XRCC4 (X-ray repair cross complementing 4) among the components of nonhomologous end-joining (NHEJ) repair complex. Conversely, overexpression of UHRF1 increased the XRCC4 expression and stable knockdown of XRCC4 sensitized retinoblastoma cells to etoposide treatment, suggesting that XRCC4 is a key mediator for the drug sensitivity upon UHRF1 depletion in retinoblastoma cells. Consistent with the findings, chromatin association of DNA ligase IV in response to acute DNA damage was found to be significantly reduced in UHRF1-depleted retinoblastoma cells and functional complementation for XRCC4 in UHRF1-depleted cells attenuated the drug sensitivity, demonstrating that XRCC4 downregulation in UHRF1-depleted cells impaired DNA repair and consequently induced robust apoptosis upon genotoxic drug treatment. In human primary retinoblastoma, high expression of UHRF1 and XRCC4 could be detected, and elevated XRCC4 expression correlated with reduced apoptosis markers, implying that UHRF1-mediated XRCC4 upregulation under pathophysiological conditions triggered by RB1 gene inactivation may confer protection against endogenous DNA damages that arise during retinoblastoma development. Taken together, these results present a new mechanistic insight into how UHRF1 mediates its tumor-promoting functions in retinoblastoma, and also provide a basis for UHRF1 targeting to improve the efficacy of current chemotherapy for retinoblastoma treatment.
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Zhang Q, Qiao L, Wang X, Ding C, Chen JJ. UHRF1 epigenetically down-regulates UbcH8 to inhibit apoptosis in cervical cancer cells. Cell Cycle 2018; 17:300-308. [PMID: 29157076 DOI: 10.1080/15384101.2017.1403686] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
UHRF1 (ubiquitin-like, containing PHD and RING finger domains 1) is an important epigenetic regulator that plays a part in DNA methylation, protein methylation and ubiquitination. It is also frequently overexpressed in many types of cancers, including cervical cancer, which is caused by human papillomavirus (HPV). In this study, we showed that UHRF1 was up-regulated in HPV oncogene E7 expressing cells and HPV-positive cervical cancer cells. We demonstrated that UHRF1 down-regulated the expression of UBE2L6 gene that encodes the ISG15-conjugating enzyme UbcH8. Overexpression of UHRF1 reduced UBE2L6 while knockdown UHRF1 elevated the expression of UBE2L6. We showed that UHRF1 regulated UBE2L6 gene by promoter hypermethylation in cervical cancer cells. Consistent with the functions of UHRF1, restored expression of UbcH8 induced apoptosis. These findings establish UBE2L6 as a novel target of UHRF1 that regulates the apoptosis function of UHRF1. Our studies suggest that UHRF1/ UbcH8 can be manipulated for therapy in cervical cancer.
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Affiliation(s)
- Qishu Zhang
- a Cancer Research Center , Shandong University School of Basic Medical Sciences , Jinan , Shandong 250012 , China
| | - Lijun Qiao
- a Cancer Research Center , Shandong University School of Basic Medical Sciences , Jinan , Shandong 250012 , China
| | - Xiao Wang
- b Department of Pathology , Shandong University School of Basic Medicine , Jinan , Shandong 250012 , China
| | - Changkuan Ding
- a Cancer Research Center , Shandong University School of Basic Medical Sciences , Jinan , Shandong 250012 , China
| | - Jason J Chen
- a Cancer Research Center , Shandong University School of Basic Medical Sciences , Jinan , Shandong 250012 , China
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Prognostic significance of XRCC4 expression in hepatocellular carcinoma. Oncotarget 2017; 8:87955-87970. [PMID: 29152133 PMCID: PMC5675685 DOI: 10.18632/oncotarget.21360] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Accepted: 08/29/2017] [Indexed: 12/26/2022] Open
Abstract
Background Our previous investigations have shown that the variants of X-ray repair complementing 4 (XRCC4) may be involved in hepatocellular carcinoma (hepatocarcinoma) tumorigenesis. This study aimed to investigate the possible prognostic significance of XRCC4 expression for hepatocarcinoma patients and possible value for the selection of transarterial chemoembolization (TACE) treatment. Materials and Methods We conducted a hospital-based retrospective analysis (including 421 hepatocarcinoma cases) to analyze the effects of XRCC4 on hepatocarcinoma prognosis and TACE. The levels of XRCC4 expression were tested using immunohistochemistry. The sensitivity of cancer cells to anti-cancer drug doxorubicin was evaluated using the half-maximal inhibitory concentration (IC50). Results XRCC4 expression was significantly correlated with pathological features including tumor stage, liver cirrhosis, and micro-vessel density. XRCC4 expression was an independent prognostic factor of hepatocarcinoma, and TACE treatments had no effects on prognosis of hepatocarcinoma patients with high XRCC4 expression. More intriguingly, TACE improved the prognosis of hepatocarcinoma patients with low XRCC4 expression. Functionally, XRCC4 overexpression increased while XRCC4 knockdown reduced the IC50 of cancer cells to doxorubicin. Conclusions These results suggest that XRCC4 may be an independent prognostic factor for hepatocarcinoma patients, and that decreasing XRCC4 expression may be beneficial for post-operative adjuvant TACE treatment in hepatocarcinoma.
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Ashraf W, Ibrahim A, Alhosin M, Zaayter L, Ouararhni K, Papin C, Ahmad T, Hamiche A, Mély Y, Bronner C, Mousli M. The epigenetic integrator UHRF1: on the road to become a universal biomarker for cancer. Oncotarget 2017; 8:51946-51962. [PMID: 28881702 PMCID: PMC5584303 DOI: 10.18632/oncotarget.17393] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 04/02/2017] [Indexed: 12/12/2022] Open
Abstract
Cancer is one of the deadliest diseases in the world causing record number of mortalities in both developed and undeveloped countries. Despite a lot of advances and breakthroughs in the field of oncology still, it is very hard to diagnose and treat the cancers at early stages. Here in this review we analyze the potential of Ubiquitin-like containing PHD and Ring Finger domain 1 (UHRF1) as a universal biomarker for cancers. UHRF1 is an important epigenetic regulator maintaining DNA methylation and histone code in the cell. It is highly expressed in a variety of cancers and is a well-known oncogene that can disrupt the epigenetic code and override the senescence machinery. Many studies have validated UHRF1 as a powerful diagnostic and prognostic tool to differentially diagnose cancer, predict the therapeutic response and assess the risk of tumor progression and recurrence. Highly sensitive, non-invasive and cost effective approaches are therefore needed to assess the level of UHRF1 in patients, which can be deployed in diagnostic laboratories to detect cancer and monitor disease progression.
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Affiliation(s)
- Waseem Ashraf
- Laboratory of Biophotonics and Pharmacology, Faculty of Pharmacy, University of Strasbourg, Illkirch, France
| | - Abdulkhaleg Ibrahim
- Institute of Genetics and Molecular and Cellular Biology, University of Strasbourg, Illkirch-Graffenstaden, France
| | - Mahmoud Alhosin
- Department of Biochemistry, Faculty of Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
- Cancer Metabolism and Epigenetic Unit, King Abdulaziz University, Jeddah, Saudi Arabia
- Cancer and Mutagenesis Unit, King Fahd Centre for Medical Research, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Liliyana Zaayter
- Laboratory of Biophotonics and Pharmacology, Faculty of Pharmacy, University of Strasbourg, Illkirch, France
| | - Khalid Ouararhni
- Institute of Genetics and Molecular and Cellular Biology, University of Strasbourg, Illkirch-Graffenstaden, France
| | - Christophe Papin
- Institute of Genetics and Molecular and Cellular Biology, University of Strasbourg, Illkirch-Graffenstaden, France
| | - Tanveer Ahmad
- Laboratory of Biophotonics and Pharmacology, Faculty of Pharmacy, University of Strasbourg, Illkirch, France
| | - Ali Hamiche
- Institute of Genetics and Molecular and Cellular Biology, University of Strasbourg, Illkirch-Graffenstaden, France
| | - Yves Mély
- Laboratory of Biophotonics and Pharmacology, Faculty of Pharmacy, University of Strasbourg, Illkirch, France
| | - Christian Bronner
- Institute of Genetics and Molecular and Cellular Biology, University of Strasbourg, Illkirch-Graffenstaden, France
| | - Marc Mousli
- Laboratory of Biophotonics and Pharmacology, Faculty of Pharmacy, University of Strasbourg, Illkirch, France
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Sharma S, Baksi R, Agarwal M. Repositioning of anti-viral drugs as therapy for cervical cancer. Pharmacol Rep 2016; 68:983-9. [DOI: 10.1016/j.pharep.2016.05.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Revised: 05/16/2016] [Accepted: 05/16/2016] [Indexed: 12/26/2022]
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Kilic S, Cracchiolo B, Gabel M, Haffty B, Mahmoud O. The relevance of molecular biomarkers in cervical cancer patients treated with radiotherapy. ANNALS OF TRANSLATIONAL MEDICINE 2015; 3:261. [PMID: 26605307 DOI: 10.3978/j.issn.2305-5839.2015.10.18] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND Radiotherapy (RT) plays an integral role in the combined-modality management of cervical cancer. Various molecular mechanisms have been implicated in the adaptive cellular response to RT. Identification of these molecular processes may permit the prediction of treatment outcome and enhanced radiation-induced cancer cell killing through tailoring of the management approach, and/or the employment of selective inhibitors of these pathways. METHODS PubMed was searched for studies presenting biomarkers of cervical cancer radioresistance validated in patient studies or in laboratory experimentation. RESULTS Several biomarkers of cervical cancer radioresistance are validated by patient survival or recurrence data. These biomarkers fall into categories of biological function including hypoxia, cell proliferation, cell-cell adhesion, and evasion of apoptosis. Additional radioresistance biomarkers have been identified in exploratory experiments. CONCLUSIONS Biomarkers of radioresistance in cervical cancer may allow molecular profiling of individual tumors, leading to tailored therapies and better prognostication and prediction of outcomes.
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Affiliation(s)
- Sarah Kilic
- 1 Department of Radiation Oncology, 2 Department of Gynecology Oncology, 3 Department of Radiation Oncology, Rutgers, the State University of New Jersey, Cancer Institute of New Jersey, New Brunswick, NJ, USA
| | - Bernadette Cracchiolo
- 1 Department of Radiation Oncology, 2 Department of Gynecology Oncology, 3 Department of Radiation Oncology, Rutgers, the State University of New Jersey, Cancer Institute of New Jersey, New Brunswick, NJ, USA
| | - Molly Gabel
- 1 Department of Radiation Oncology, 2 Department of Gynecology Oncology, 3 Department of Radiation Oncology, Rutgers, the State University of New Jersey, Cancer Institute of New Jersey, New Brunswick, NJ, USA
| | - Bruce Haffty
- 1 Department of Radiation Oncology, 2 Department of Gynecology Oncology, 3 Department of Radiation Oncology, Rutgers, the State University of New Jersey, Cancer Institute of New Jersey, New Brunswick, NJ, USA
| | - Omar Mahmoud
- 1 Department of Radiation Oncology, 2 Department of Gynecology Oncology, 3 Department of Radiation Oncology, Rutgers, the State University of New Jersey, Cancer Institute of New Jersey, New Brunswick, NJ, USA
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Liu W, Qiao RH, Wang DM, Huang XW, Li B, Wang D. UHRF1 promotes human osteosarcoma cell invasion by downregulating the expression of E‑cadherin in an Rb1‑dependent manner. Mol Med Rep 2015; 13:315-20. [PMID: 26548607 DOI: 10.3892/mmr.2015.4515] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Accepted: 09/25/2015] [Indexed: 11/06/2022] Open
Abstract
Ubiquitin‑like with plant homeodomain (PHD) and RING‑finger domain 1 (UHRF1) maintains methylation patterns following DNA replication and is expressed at high levels in various types of human cancer. UHRF1 has been identified as a novel oncogene involved in the pathogenesis of hepatocellular carcinoma. Previous studies have demonstrated that inhibition of the expression of UHRF1 suppresses the proliferation of cancer cells. However, the role of UHRF1 in human osteosarcoma has not been investigated. The present study examined the expression levels of UHRF1 and retinoblastoma 1 (Rb1) in human osteosarcoma cell lines by western blot analysis. Stable overexpression of UHRF1 or knockdown of Rb1 was achieved by lentiviral transfection. Subsequently, a Cell Counting Kit-8 assay and a cell invasion assay were performed to detect the biological functions of UHRF1 in vitro. The results of the present study demonstrated that UHRF1 promoted the proliferation of human osteosarcoma cells. The present study also reported that UHRF1 was able to enhance the invasion of osteosarcoma cells in a retinoblastoma 1 (Rb1)‑dependent manner. UHRF1 promoted invasion in Rb1‑positive osteosarcoma cells, but not in Saos‑2 cells with homozygous loss of Rb1. Similarly, knockdown of Rb1 in Rb1‑positive osteosarcoma cells enhanced levels of invasion and eliminated the regulation of invasion by UHRF1. UHRF1 was found to inhibit the mRNA and protein expression levels of Rb1. Furthermore, deletion of Rb1 was found to suppress the expression of E‑cadherin and promote epithelial‑to‑mesenchymal transition (EMT). In addition, the overexpression of UHRF1 inhibited the expression of E‑cadherin and promoted EMT via the suppression of Rb1. These data demonstrated that UHRF1 promotes osteosarcoma cell invasion by downregulating the expression of E‑cadherin and increasing EMT in an Rb1‑dependent manner.
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Affiliation(s)
- Wei Liu
- Department of Orthopedics, Second Clinical Medical College, Shanxi Medical University, Taiyuan, Shanxi 215006, P.R. China
| | - Rui Hong Qiao
- Department of Orthopedics, Second Clinical Medical College, Shanxi Medical University, Taiyuan, Shanxi 215006, P.R. China
| | - Dong Ming Wang
- Department of Orthopedics, Second Clinical Medical College, Shanxi Medical University, Taiyuan, Shanxi 215006, P.R. China
| | - Xiao Wei Huang
- Department of Gastroenterology, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, Hubei 226001, P.R. China
| | - Bing Li
- Department of Orthopedics, Second Clinical Medical College, Shanxi Medical University, Taiyuan, Shanxi 215006, P.R. China
| | - Dong Wang
- Department of Orthopedics, Second Clinical Medical College, Shanxi Medical University, Taiyuan, Shanxi 215006, P.R. China
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Huang HJ, Zhang M. Downregulation of PI3Kcb utilizing adenovirus-mediated transfer of siRNA attenuates bone cancer pain. INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL PATHOLOGY 2014; 7:8127-35. [PMID: 25550861 PMCID: PMC4270548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 07/20/2014] [Accepted: 08/23/2014] [Indexed: 06/04/2023]
Abstract
Phosphatidylinositol 3-kinase (PI3K) signaling plays a pivotal role in intracellular signal transduction pathways involved in chronic pain states. PI3K is implicated in pathomechanisms of enhanced synaptic strength, such as wind-up and central sensitization in the spinal dorsal horn. The PI3Kcb gene encoding the class 1A PI3K catalytic subunit p110beta is one of the most important molecular of the P13K signaling pathway. Here, we used small interfering RNA (siRNA) targeted to PI3Kcb by adenovirus-mediated transfer, to determine whether inhibition of PI3Kcb was a potential therapeutic target for bone cancer pain (BCP). In this study, treatment of BCP model in rats with PI3Kcb-specific siRNA resulted in inhibited pain-related behavior. Depletion of PI3Kcb decreased the protein levels of spinal PI3Kcb and phospho-Akt (P-Akt)-downstream targets of PI3K. Knockdown of PI3Kcb by siRNA also induced decreased expression of GFAP and OX42, suggesting that the upregulation of spinal PI3Kcb may increase glia excitability, at least in part by regulating glia message. Our findings suggest that siRNA-mediated gene silencing of PI3Kcb may be a useful therapeutic strategy for BCP.
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Affiliation(s)
- Huan-Jun Huang
- Department of Gastroenterology, Tongji Hospital of Tongji Medical College, Huazhong University of Science and TechnologyWuhan 430022, Hubei, PR China
| | - Mei Zhang
- Department of Neurology, Wuhan Central HospitalWuhan 430014, Hubei, PR China
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Tang FR, Loke WK. Molecular mechanisms of low dose ionizing radiation-induced hormesis, adaptive responses, radioresistance, bystander effects, and genomic instability. Int J Radiat Biol 2014; 91:13-27. [DOI: 10.3109/09553002.2014.937510] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Yang C, Wang Y, Zhang F, Sun G, Li C, Jing S, Liu Q, Cheng Y. Inhibiting UHRF1 expression enhances radiosensitivity in human esophageal squamous cell carcinoma. Mol Biol Rep 2013; 40:5225-35. [PMID: 23943380 DOI: 10.1007/s11033-013-2559-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Accepted: 04/29/2013] [Indexed: 12/15/2022]
Abstract
Radiotherapy is an effective treatment for some esophageal cancers, but the molecular mechanisms of radiosensitivity remain unknown. Ubiquitin-like with PHD and ring finger domains 1 (UHRF1) is a novel nuclear protein which is overexpressed in various cancers but not yet examined in esophageal squamous cell carcinoma (ESCC). The correlation between UHRF1 and the radioresistance in ESCC is still unclear. In the present study, the expression of UHRF1 was examined by immunohistochemistry in specimens of ESCC patients treated with radiotherapy. The results showed that UHRF1 was significantly overexpressed in ESCC specimens. Overexpression of UHRF1 correlated significantly with advanced T-stage, positive lymph node metastasis and poor differentiation. In addition, UHRF1 was associated with radiotherapy response, in which overexpression of UHRF1 was observed more frequently in the radioresistant group than in the effective group. At the molecular level, inhibition of UHRF1 by lentivirus-mediated shRNA targeting UHRF1 increased the radiosensitivity and apoptosis, while decreased radiation-induced G2/M phase arrest in TE-1 cells. Moreover, inhibition of UHRF1 resulted in higher residual γH2AX expression after irradiation, but not initial γH2AX. Further study showed that inhibition of UHRF1 down-regulated the endogenous expressions of DNA repair protein Ku70 and Ku80 in TE-1 cells, and significantly inhibited the increase of these proteins after irradiation. Above all, our data suggested that UHRF1 might play an important role in radioresistance of ESCC, and inhibition of UHRF1 can increase the radiosensitivity of TE-1 cells by altering cell cycle progression, enhancing apoptosis, and decreasing DNA damage repair capacity.
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Affiliation(s)
- Congrong Yang
- Department of Radiation Oncology, The Fourth Hospital of Hebei Medical University, Shijiazhuang, 050011, China
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Krifa M, Alhosin M, Muller CD, Gies JP, Chekir-Ghedira L, Ghedira K, Mély Y, Bronner C, Mousli M. Limoniastrum guyonianum aqueous gall extract induces apoptosis in human cervical cancer cells involving p16 INK4A re-expression related to UHRF1 and DNMT1 down-regulation. J Exp Clin Cancer Res 2013; 32:30. [PMID: 23688286 PMCID: PMC3695779 DOI: 10.1186/1756-9966-32-30] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Accepted: 05/17/2013] [Indexed: 12/23/2022] Open
Abstract
Several reports have described the potential effects of natural compounds as anti-cancer agents in vitro as well as in vivo. The aim of this study was to evaluate the anti-cancer effect of Limoniastrum guyonianum aqueous gall extract (G extract) and luteolin in the human cervical cancer HeLa cell line, and, if so, to clarify the underlying mechanism. Our results show that G extract and luteolin inhibited cell proliferation and induced G2/M cell cycle arrest in a concentration and time-dependent manner. Both natural products induced programmed cell death as confirmed by the presence of hypodiploid G0/G1 cells. These effects are associated with an up-regulation of the expression of the tumor suppressor gene p16INK4A and a down-regulation of the expression of the anti-apoptotic actor UHRF1 and its main partner DNMT1. Moreover, G extract- and luteolin-induced UHRF1 and DNMT1 down-regulation is accompanied with a global DNA hypomethylation in HeLa cell line. Altogether our results show that G extract mediates its growth inhibitory effects on human cervical cancer HeLa cell line likely via the activation of a p16INK4A-dependent cell cycle checkpoint signalling pathway orchestrated by UHRF1 and DNMT1 down-regulation.
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Affiliation(s)
- Mounira Krifa
- UMR CNRS 7213, Laboratoire de Biophotonique et Pharmacologie, Faculté de Pharmacie, Université de Strasbourg, 74 Route du Rhin, CS 60024, Illkirch, Cedex F-67401, France
- Unité de Pharmacognosie/Biologie Moléculaire 99/UR/07-03. Faculté de Pharmacie de Monastir, Rue Avicenne 5000, Monastir, Tunisie
| | - Mahmoud Alhosin
- UMR CNRS 7213, Laboratoire de Biophotonique et Pharmacologie, Faculté de Pharmacie, Université de Strasbourg, 74 Route du Rhin, CS 60024, Illkirch, Cedex F-67401, France
| | - Christian D Muller
- UMR CNRS 7200, Laboratoire d’Innovation Thérapeutique, Université de Strasbourg, Faculté de Pharmacie, 74 route du Rhin, 67401 Illkirch, France
| | - Jean-Pierre Gies
- UMR CNRS 7213, Laboratoire de Biophotonique et Pharmacologie, Faculté de Pharmacie, Université de Strasbourg, 74 Route du Rhin, CS 60024, Illkirch, Cedex F-67401, France
| | - Leila Chekir-Ghedira
- Unité de Pharmacognosie/Biologie Moléculaire 99/UR/07-03. Faculté de Pharmacie de Monastir, Rue Avicenne 5000, Monastir, Tunisie
| | - Kamel Ghedira
- Unité de Pharmacognosie/Biologie Moléculaire 99/UR/07-03. Faculté de Pharmacie de Monastir, Rue Avicenne 5000, Monastir, Tunisie
| | - Yves Mély
- UMR CNRS 7213, Laboratoire de Biophotonique et Pharmacologie, Faculté de Pharmacie, Université de Strasbourg, 74 Route du Rhin, CS 60024, Illkirch, Cedex F-67401, France
| | - Christian Bronner
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM, Parc d’innovation, 1 rue Laurent Fries, Illkirch, Cedex 67404, France
| | - Marc Mousli
- UMR CNRS 7213, Laboratoire de Biophotonique et Pharmacologie, Faculté de Pharmacie, Université de Strasbourg, 74 Route du Rhin, CS 60024, Illkirch, Cedex F-67401, France
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Sun KK, Ji C, Li X, Zhang L, Deng J, Zhong N, Wu XY. Overexpression of high mobility group protein B1 correlates with the proliferation and metastasis of lung adenocarcinoma cells. Mol Med Rep 2013; 7:1678-82. [PMID: 23467607 DOI: 10.3892/mmr.2013.1362] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2012] [Accepted: 02/27/2013] [Indexed: 11/06/2022] Open
Abstract
High mobility group protein B1 (HMGB1) plays an important role in a number of clinical conditions, such as autoimmunity, cardiovascular disease and cancer. Evidence suggests that HMGB1 is critical in the development and progression of numerous types of tumor. However, the underlying molecular mechanisms for the HMGB1-mediated progression and metastasis of lung cancer have not yet been elucidated. In this study, we investigated the role of HMGB1 in lung adenocarcinoma and the mechanisms by which it contributes to carcinogenesis and metastasis. We demonstrated that there was an increase in the expression of HMGB1 in primary cancer tissues compared to the matched adjacent non-cancerous tissues. The expression levels of TOB1 in the normal human bronchial epithelial (HBE) cell line and 10 lung cancer cell lines were determined by reverse transcription-PCR (RT-PCR). The results revealed that HMGB1 expression increased in 8 cell lines compared with the HBE cell line. The A549 and NCI-H1975 cells were transfected with HMGB1 recombinant plasmid. We discovered that the overexpression of HMGB1 promoted cell growth and metastasis in the 2 cell lines. Further investigation revealed that exogenously expressed HMGB1 enhanced the activation of p38 and Erk1/2, in addition to the expression of nuclear factor (NF)-κB. We propose that HMGB1 functions as a tumor promoter and that it regulates the proliferation and invasion of lung cancer cells by modulating the activation of the Erk1/2 and p38 mitogen-activated protein kinase (MAPK) signaling pathways.
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Affiliation(s)
- Ke-Kang Sun
- Department of Gastrointestinal Surgery, Thoracic Surgery Division, Kunshan First People's Hospital Affiliated to Jiangsu University, Kunshan, Jiangsu 215300, PR China
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Che J, Zhang FZ, Zhao CQ, Hu XD, Fan SJ. Cyclopamine is a novel Hedgehog signaling inhibitor with significant anti-proliferative, anti-invasive and anti-estrogenic potency in human breast cancer cells. Oncol Lett 2013; 5:1417-1421. [PMID: 23599805 PMCID: PMC3629107 DOI: 10.3892/ol.2013.1195] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2012] [Accepted: 02/04/2013] [Indexed: 01/22/2023] Open
Abstract
Stimulation of Hedgehog (Hh) signaling induces carcinogenesis or promotes cell survival in cancers of multiple organs. In epithelial cancer with aberrant Hedgehog activation, abrogation of Hedgehog signaling by cyclopamine, a naturally occurring Hedgehog-specific small-molecule inhibitor, causes profound inhibition of tumor growth. In the present study, cyclopamine displayed a significant potency in suppressing the proliferation of both estrogen-responsive (MCF-7) and estrogen-independent (MDA-MB-231) human breast cancer cells. Cyclopamine induced a robust G1 cell cycle arrest and elicited notable effects on the expression of cyclin D1 through modulation of the MAPK/ERK signaling pathway. Cyclopamine also inhibited the invasive ability of both breast cancer cell lines by suppressing the expression levels of NF-κB, MMP2 and MMP9 protein. Furthermore, in estrogen-responsive MCF-7 cells, cyclopamine significantly downregulated the production of estrogen receptor-α protein. Our results implicate cyclopamine as a novel, potent inhibitor of human breast cancer proliferation and estrogen responsiveness that could potentially be developed into a promising therapeutic agent for the treatment of breast cancer.
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Affiliation(s)
- Jun Che
- Key Laboratory of Radiation Biology, School of Radiation Medicine and Protection, Medical College of Soochow University, Suzhou, Jiangsu 215123; ; Department of Radiation Oncology, The Fourth Hospital Affiliated to Soochow University, Wuxi, Jiangsu 214062, P.R. China
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Abstract
UHRF1 (ubiquitin-like, with PHD and RING finger domains 1) is a critical epigenetic player involved in the maintenance of DNA methylation patterns during DNA replication. Dysregulation of the UHRF1 level is implicated in cancer onset, metastasis, and tumor recurrence. Previous studies demonstrated that UHRF1 can be stabilized through USP7-mediated deubiquitylation, but the mechanism through which UHRF1 is ubiquitylated is still unknown. Here we show that proteasomal degradation of UHRF1 is mediated by the SCF(β-TrCP) E3 ligase. Through bioinformatic and mutagenesis studies, we identified a functional DSG degron in the UHRF1 N terminus that is necessary for UHRF1 stability regulation. We further show that UHRF1 physically interacts with β-TrCP1 in a manner dependent on phosphorylation of serine 108 (S108(UHRF1)) within the DSG degron. Furthermore, we demonstrate that S108(UHRF1) phosphorylation is catalyzed by casein kinase 1 delta (CK1δ) and is important for the recognition of UHRF1 by SCF(β-TrCP). Importantly, we demonstrate that UHRF1 degradation is accelerated in response to DNA damage, coincident with enhanced S108(UHRF1) phosphorylation. Taken together, our data identify SCF(β-TrCP) as a bona fide UHRF1 E3 ligase important for regulating UHRF1 steady-state levels both under normal conditions and in response to DNA damage.
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Oh JH, Wong HP, Wang X, Deasy JO. A bioinformatics filtering strategy for identifying radiation response biomarker candidates. PLoS One 2012; 7:e38870. [PMID: 22768051 PMCID: PMC3387230 DOI: 10.1371/journal.pone.0038870] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2012] [Accepted: 05/15/2012] [Indexed: 02/06/2023] Open
Abstract
The number of biomarker candidates is often much larger than the number of clinical patient data points available, which motivates the use of a rational candidate variable filtering methodology. The goal of this paper is to apply such a bioinformatics filtering process to isolate a modest number (<10) of key interacting genes and their associated single nucleotide polymorphisms involved in radiation response, and to ultimately serve as a basis for using clinical datasets to identify new biomarkers. In step 1, we surveyed the literature on genetic and protein correlates to radiation response, in vivo or in vitro, across cellular, animal, and human studies. In step 2, we analyzed two publicly available microarray datasets and identified genes in which mRNA expression changed in response to radiation. Combining results from Step 1 and Step 2, we identified 20 genes that were common to all three sources. As a final step, a curated database of protein interactions was used to generate the most statistically reliable protein interaction network among any subset of the 20 genes resulting from Steps 1 and 2, resulting in identification of a small, tightly interacting network with 7 out of 20 input genes. We further ranked the genes in terms of likely importance, based on their location within the network using a graph-based scoring function. The resulting core interacting network provides an attractive set of genes likely to be important to radiation response.
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Affiliation(s)
- Jung Hun Oh
- Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York, United States of America
| | - Harry P. Wong
- Department of Infectious Diseases, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Xiaowei Wang
- Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Joseph O. Deasy
- Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York, United States of America
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Jiao Y, Sun KK, Zhao L, Xu JY, Wang LL, Fan SJ. Suppression of human lung cancer cell proliferation and metastasis in vitro by the transducer of ErbB-2.1 (TOB1). Acta Pharmacol Sin 2012; 33:250-60. [PMID: 22158108 DOI: 10.1038/aps.2011.163] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
AIM To investigate the effects of the transducer of ErbB-2.1 (TOB1) on the proliferation, migration and invasion of human lung cancer cells in vitro. METHODS Human lung cancer cell lines (95-D, A549, NCI-H1299, NCI-H1975, NCI-H661, NCI-H446, NCI-H1395, and Calu-3) and the normal human bronchial epithelial (HBE) cell line were tested. The expression levels of TOB1 in the cells were determined with Western blot and RT-PCR analyses. TOB1-overexpressing cell line 95-D/TOB1 was constructed using lipofectamine-induced TOB1 recombinant plasmid transfection and selective G418 cell culture. The A549 cells were transcend-transfected with TOB1-siRNA. MTT assay, flow cytometry and Western blot analysis were used to examine the effects of TOB1 on cancer cell proliferation and wound healing. Transwell invasive assay was performed to evaluate the effects of TOB1 on cancer cell migration and invasion. The activity of MMP2 and MMP9 was measured using gelatin zymography assay. RESULTS The expression levels of TOB1 in the 8 human lung cancer cell lines were significantly lower than that in HBE cells. TOB1 overexpression inhibited the proliferation of 95-D cells, whereas TOB1 knockdown with TOB1-siRNA promoted the growth of A549 cells. Decreased cell migration and invasion were detected in 95-D/TOB1 cells, and the suppression of TOB1 enhanced the metastasis in A549 cells. TOB1 overexpression not only increased the expression of the phosphatase and tensin homolog (PTEN), an important tumor suppressor, but also regulated the downstream effectors in the PI3K/PTEN signaling pathway, including Akt, ERK1/2, etc. In contrast, decreased expression of TOB1 oppositely regulated the expression of these factors. TOB1 also regulates the gelatinase activity of MMP2 and MMP9 in lung cancer cells. CONCLUSION The results demonstrate that the PI3K/PTEN pathway, which is essential for carcinogenesis, angiogenesis, and metastasis, may be one of the possible signaling pathways for regulation of proliferation and metastasis of human lung cancer cells by TOB1 in vitro.
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Li X, Meng Q, Rosen EM, Fan S. UHRF1 confers radioresistance to human breast cancer cells. Int J Radiat Biol 2010; 87:263-73. [PMID: 21067293 DOI: 10.3109/09553002.2011.530335] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
PURPOSE To investigate the effect of ubiquitin-like with plant homeodomain (PHD) and ring finger domains 1 (UHRF1) overexpression on radiosensitivity to X-rays in human breast cancer MDA-MB-231 cells. MATERIALS AND METHODS Cell survival was determined by colony formation assay; cell cycle distribution was measured by flow cytometry; apoptosis was evaluated by DNA fragmentation assay and Annexin V apoptosis detection kit; protein expression was analysed by Western blot assay; chromosome aberrations (centric rings and dicentrics) were assayed by conventional chromosome analysis. RESULTS A significant decrease of radiosensitivity to X-rays was observed in MDA-MB-231 cells transfected with a full-length of human UHRF1 cDNA (MDA-MB-231/UHRF1) compared to the control cells (MDA-MB-231/parental and MDA-MB-231/pcDNA3 [mammalian expression vector]), and the similar results were observed in MDA-MB-468 cells. In contrast, a decreased expression of UHRF1 by a specific UHRF1-small interfering RNA (siRNA) significantly enhanced cell radiosensitivity. The UHRF1-mediated radioresistance was correlated with a G2(Ra)/M arrest, a decreased induction of apoptosis, a down-regulation of the pro-apoptotic protein anti-B cell lymphoma/leukemia 2 (bcl-2) associated X protein (Bax) and a up-regulation of the DNA damage repair proteins Lupus Ku autoantigen protein p70 (Ku-70) and Lupus Ku autoantigen protein p80 (Ku-80). Furthermore, chromosomal aberrations (centric rings and dicentrics) by X-rays were less in MDA-MB-231/UHRF1 than in MDA-MB-231/parental and MDA-MB-231/pcDNA3 control cells. CONCLUSIONS These results suggested that UHRF1 may be a new target in the radiotherapy of breast cancer via affecting apoptosis and DNA damage repair.
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Affiliation(s)
- Xinli Li
- School of Radiation Medicine and Public Health, Medical College of Soochow University, Suzhou, Jiangsu, P. R. China
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