1
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Atri Y, Bharti H, Sahani N, Sarkar DP, Nag A. CUL4A silencing attenuates cervical carcinogenesis and improves Cisplatin sensitivity. Mol Cell Biochem 2024; 479:1041-1058. [PMID: 37285039 DOI: 10.1007/s11010-023-04776-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 05/21/2023] [Indexed: 06/08/2023]
Abstract
CUL4A is an ubiquitin ligase deregulated in numerous pathologies including cancer and even hijacked by viruses for facilitating their survival and propagation. However, its role in Human papilloma virus (HPV)-mediated cervical carcinogenesis remains elusive. The UALCAN and GEPIA datasets were analyzed to ascertain the transcript levels of CUL4A in cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC) patients. Subsequently, various biochemical assays were employed to explore the functional contribution of CUL4A in cervical carcinogenesis and to shed some light on its involvement in Cisplatin resistance in cervical cancer. Our UALCAN and GEPIA datasets analyses reveal elevated CUL4A transcript levels in cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC) patients that correlate with adverse clinicopathological parameters such as tumor stage and lymph node metastasis. Kaplan-Meier plot and GEPIA assessment depict poor prognosis of CESC patients having high CUL4A expression. Varied biochemical assays illustrate that CUL4A inhibition severely curtails hallmark malignant properties such as cellular proliferation, migration, and invasion of cervical cancer cells. We also show that CUL4A knockdown in HeLa cells causes increased susceptibility and better apoptotic induction toward Cisplatin, a mainstay drug used in cervical cancer treatment. More interestingly, we find reversion of Cisplatin-resistant phenotype of HeLa cells and an augmented cytotoxicity towards the platinum compound upon CUL4A downregulation. Taken together, our study underscores CUL4A as a cervical cancer oncogene and illustrates its potential as a prognosis indicator. Our investigation provides a novel avenue in improving current anti-cervical cancer therapy and overcoming the bottle-neck of Cisplatin resistance.
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Affiliation(s)
- Yama Atri
- Department of Biochemistry, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021, India
| | - Hina Bharti
- Department of Biochemistry, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021, India
| | - Nandini Sahani
- Department of Biochemistry, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021, India
| | - Debi P Sarkar
- Department of Biochemistry, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021, India
| | - Alo Nag
- Department of Biochemistry, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021, India.
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2
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Lung J, Chen YC, Lin YC, Li YC, You L, Jablons DM, Mao JH, Yang CT, Hung MS. The effect of cullin 4A on lung cancer cell chemosensitivity to paclitaxel through p33ING1b regulation. Am J Transl Res 2021; 13:11194-11208. [PMID: 34786051 PMCID: PMC8581858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 08/12/2021] [Indexed: 06/13/2023]
Abstract
Cullin 4A (Cul4A) reportedly has oncogenic roles in several cancer types by regulating tumor suppressors through the ubiquitination and proteolysis of the tumor suppressor. In addition, Cul4A is associated with chemosensitivity to chemotherapy drugs. This study investigated the association between Cul4A and lung cancer cell chemosensitivity to paclitaxel, particularly with respect to the role of the p33 inhibitor of the growth 1 (p33ING1b) tumor suppressor. The results showed that the Cul4A knockdown upregulated the p33ING1b expression in lung cancer cells and increased the lung cancer cell and mice tumor xenograft chemosensitivity to paclitaxel. The Cul4A knockdown also inhibited the growth and increased the apoptosis in the tumor xenografts treated with paclitaxel. Notably, the p33ING1b overexpression increased the lung cancer cell chemosensitivity to paclitaxel, but the p33ING1b knockdown reduced the chemosensitivity. A further analysis demonstrated that Cul4A regulates the expression of p33ING1b through protein-protein interactions, ubiquitination, and protein degradation. In conclusion, the present findings suggest that Cul4A mediates the chemosensitivity of lung cancer cells to paclitaxel by regulating p33ING1b. These findings may offer novel insights into future therapeutic strategies for lung cancer that target Cul4A.
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Affiliation(s)
- Jrhau Lung
- Department of Medical Research, Chang Gung Memorial Hospital, Chiayi BranchChiayi 61363, Taiwan
| | - Yi-Chuan Chen
- Department of Emergency Medicine, Madou Sin-Lau Hospital, The Presbyterian Church in TaiwanTainan 72100, Taiwan
| | - Yu-Ching Lin
- Department of Medicine, College of Medicine, Chang Gung UniversityTaoyuan 33323, Taiwan
- Department of Pulmonary and Critical Care Medicine, Chang Gung Memorial Hospital, Chiayi BranchChiayi 61363, Taiwan
- Department of Respiratory Care, Chang Gung University of Science and Technology, Chiayi CampusChiayi 61363, Taiwan
| | - Ya-Chin Li
- Department of Pulmonary and Critical Care Medicine, Chang Gung Memorial Hospital, Chiayi BranchChiayi 61363, Taiwan
| | - Liang You
- Thoracic Oncology Laboratory, Department of Surgery, Comprehensive Cancer Center, University of CaliforniaSan Francisco, CA 94143, USA
| | - David M Jablons
- Thoracic Oncology Laboratory, Department of Surgery, Comprehensive Cancer Center, University of CaliforniaSan Francisco, CA 94143, USA
| | - Jian-Hua Mao
- Lawrence Berkeley National Laboratory, Life Sciences DivisionOne Cyclotron Road, Berkeley, California, CA 94720, USA
| | - Cheng-Ta Yang
- Department of Respiratory Care, College of Medicine, Chang Gung UniversityTaoyuan 33323, Taiwan
- Department of Pulmonary and Critical Care Medicine, Chang Gung Memorial Hospital, Taoyuan BranchTaoyuan 33378, Taiwan
| | - Ming-Szu Hung
- Department of Medicine, College of Medicine, Chang Gung UniversityTaoyuan 33323, Taiwan
- Department of Pulmonary and Critical Care Medicine, Chang Gung Memorial Hospital, Chiayi BranchChiayi 61363, Taiwan
- Department of Respiratory Care, Chang Gung University of Science and Technology, Chiayi CampusChiayi 61363, Taiwan
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3
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Wu K, Hopkins BD, Sanchez R, DeVita RJ, Pan ZQ. Targeting Cullin-RING E3 Ubiquitin Ligase 4 by Small Molecule Modulators. JOURNAL OF CELLULAR SIGNALING 2021; 2:195-205. [PMID: 34604860 PMCID: PMC8486283 DOI: 10.33696/signaling.2.051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Cullin-RING E3 ubiquitin ligase 4 (CRL4) plays an essential role in cell cycle progression. Recent efforts using high throughput screening and follow up hit-to-lead studies have led to identification of small molecules 33-11 and KH-4-43 that inhibit E3 CRL4's core ligase complex and exhibit anticancer potential. This review provides: 1) an updated perspective of E3 CRL4, including structural organization, major substrate targets and role in cancer; 2) a discussion of the challenges and strategies for finding the CRL inhibitor; and 3) a summary of the properties of the identified CRL4 inhibitors as well as a perspective on their potential utility to probe CRL4 biology and act as therapeutic agents.
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Affiliation(s)
- Kenneth Wu
- Department of Oncological Sciences, The Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029-6574, USA
| | - Benjamin D Hopkins
- Department of Oncological Sciences, The Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029-6574, USA.,Genetics and Genomics, The Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029-6574, USA
| | - Roberto Sanchez
- Department of Pharmacological Sciences, The Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029-6574, USA.,Drug Discovery Institute, The Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029-6574, USA
| | - Robert J DeVita
- Department of Pharmacological Sciences, The Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029-6574, USA.,Drug Discovery Institute, The Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029-6574, USA
| | - Zhen-Qiang Pan
- Department of Oncological Sciences, The Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029-6574, USA
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4
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Wang Y, Yan F, Nasar A, Chen ZS, Altorki NK, Stiles B, Narula N, Zhou P. CUL4 high Lung Adenocarcinomas Are Dependent on the CUL4-p21 Ubiquitin Signaling for Proliferation and Survival. THE AMERICAN JOURNAL OF PATHOLOGY 2021; 191:1638-1650. [PMID: 34119472 PMCID: PMC8420861 DOI: 10.1016/j.ajpath.2021.05.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 05/16/2021] [Accepted: 05/21/2021] [Indexed: 11/20/2022]
Abstract
Cullin (CUL) 4A and 4B ubiquitin ligases are often highly accumulated in human malignant neoplasms and are believed to possess oncogenic properties. However, the underlying mechanisms by which CUL4A and CUL4B promote pulmonary tumorigenesis remain largely elusive. This study reports that CUL4A and CUL4B are highly expressed in patients with non-small cell lung cancer (NSCLC), and their high expression is associated with disease progression, chemotherapy resistance, and poor survival in adenocarcinomas. Depletion of CUL4A (CUL4Ak/d) or CUL4B (CUL4Bk/d) leads to cell cycle arrest at G1 and loss of proliferation and viability of NSCLC cells in culture and in a lung cancer xenograft model, suggesting that CUL4A and 4B are oncoproteins required for tumor maintenance of certain NSCLCs. Mechanistically, increased accumulation of the cell cycle-dependent kinase inhibitor p21/Cip1/WAF1 was observed in lung cancer cells on CUL4 silencing. Knockdown of p21 rescued the G1 arrest of CUL4Ak/d or CUL4Bk/d NSCLC cells, and allowed proliferation to resume. These findings reveal that p21 is the primary downstream effector of lung adenocarcinoma dependence on CUL4, highlight the notion that not all substrates respond equally to abrogation of the CUL4 ubiquitin ligase in NSCLCs, and imply that CUL4Ahigh/CUL4Bhigh may serve as a prognostic marker and therapeutic target for patients with NSCLC.
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Affiliation(s)
- Yannan Wang
- Department of Pathology and Laboratory Medicine, The Joan and Stanford I. Weill Medical College of Cornell University, New York, New York
| | - Fan Yan
- Department of Pathology and Laboratory Medicine, The Joan and Stanford I. Weill Medical College of Cornell University, New York, New York
| | - Abu Nasar
- Division of Thoracic Surgery, Department of Cardiothoracic Surgery, Weill Cornell Medicine - New York Presbyterian Hospital, New York, New York
| | - Zhe-Sheng Chen
- Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, St John's University, Queens, New York
| | - Nasser Khaled Altorki
- Division of Thoracic Surgery, Department of Cardiothoracic Surgery, Weill Cornell Medicine - New York Presbyterian Hospital, New York, New York
| | - Brendon Stiles
- Division of Thoracic Surgery, Department of Cardiothoracic Surgery, Weill Cornell Medicine - New York Presbyterian Hospital, New York, New York
| | - Navneet Narula
- Department of Pathology and Laboratory Medicine, The Joan and Stanford I. Weill Medical College of Cornell University, New York, New York
| | - Pengbo Zhou
- Department of Pathology and Laboratory Medicine, The Joan and Stanford I. Weill Medical College of Cornell University, New York, New York.
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5
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Cao Y, Li P, Wang H, Li L, Li Q. SIRT3 promotion reduces resistance to cisplatin in lung cancer by modulating the FOXO3/CDT1 axis. Cancer Med 2021; 10:1394-1404. [PMID: 33655712 PMCID: PMC7926010 DOI: 10.1002/cam4.3728] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 11/18/2020] [Accepted: 11/30/2020] [Indexed: 01/02/2023] Open
Abstract
Background Cisplatin is an extensively used chemotherapy agent for lung cancer, but its drug resistance serves as a huge obstacle for chemotherapy failure of lung cancer patients. Hence, researchers aimed to determine role of sirtuin 3 (SIRT3) considering its action in cisplatin resistance of lung cancer. Methods The expression patterns of SIRT3, FOXO3, and CDT1 were determined using RT‐qPCR and Immunoblotting in lung cancer. Immunofluorescence and Co‐IP were adopted to detect co‐localization and interaction of FOXO3 and CDT1. Loss‐ and gain‐function assays were conducted to determine roles of SIRT3, FOXO3, and CDT1 in resulting pathological changes, while biological behavior of cells was determined using a combination of CCK‐8, flow cytometry, colony formation, and Transwell assays. The effects of SIRT3 and CDT1 were determined in the nude mice xenografted with the tumor. The proliferation‐, angiogenesis‐, and apoptosis‐associated factors levels were determined using Immunoblotting. Results SIRT3, FOXO3, and CDT1 expression was suppressed in the lung cancer tissues and cells. FOXO3 positively regulates the CDT1 expression pattern and SIRT3 elevation inhibits FOXO3 at the acetylated level, thus, elevating FOXO3 expression. The elevation of SIRT3, FOXO3, or CDT1 inhibited cell cisplatin resistance of lung cancer cells as well as inhibited viability, proliferation, and invasion in vitro. In vivo experiments, SIRT3 depletion elevated Ki‐67 and VEGFA levels, but downregulated cleaved caspase 3 level. Conclusion Collectively, overexpressed SIRT3 elevates expression of FOXO3a/CDT1 axis, thus, contributing to enhanced sensitivity of lung cancer cells.
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Affiliation(s)
- Yang Cao
- The Third Department of Medical Oncology, the Third People's Hospital of Zhengzhou, Zhengzhou, P. R. China
| | - Ping Li
- Medical Department, Women & Infants Hospital of Zhengzhou, Zhengzhou, P. R. China
| | - Haicun Wang
- The Third Department of Medical Oncology, the Third People's Hospital of Zhengzhou, Zhengzhou, P. R. China
| | - Lei Li
- The Third Department of Medical Oncology, the Third People's Hospital of Zhengzhou, Zhengzhou, P. R. China
| | - Quanwang Li
- Department of Oncology, Dongfang Hospital of Beijing University of Chinese Medicine, Beijing, P. R. China
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6
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Meerang M, Kreienbühl J, Orlowski V, Müller SLC, Kirschner MB, Opitz I. Importance of Cullin4 Ubiquitin Ligase in Malignant Pleural Mesothelioma. Cancers (Basel) 2020; 12:cancers12113460. [PMID: 33233664 PMCID: PMC7699720 DOI: 10.3390/cancers12113460] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 11/04/2020] [Accepted: 11/17/2020] [Indexed: 12/26/2022] Open
Abstract
Neurofibromatosis type 2 (NF2), the tumor suppressor frequently lost in malignant pleural mesothelioma (MPM), suppresses tumorigenesis in part by inhibiting the Cullin4 ubiquitin ligase (CUL4) complex in the nucleus. Here, we evaluated the importance of CUL4 in MPM progression and tested the efficacy of cullin inhibition by pevonedistat, a small molecule inhibiting cullin neddylation. CUL4 paralogs (CUL4A and CUL4B) were upregulated in MPM tumor specimens compared to nonmalignant pleural tissues. High gene and protein expressions of CUL4B was associated with a worse progression-free survival of MPM patients. Among 13 MPM cell lines tested, five (38%) were highly sensitive to pevonedistat (half maximal inhibitory concentration of cell survival IC50 < 0.5 µM). This remained true in a 3D spheroid culture. Pevonedistat treatment caused the accumulation of CDT1 and p21 in both sensitive and resistant cell lines. However, the treatment induced S/G2 cell cycle arrest and DNA rereplication predominantly in the sensitive cell lines. In an in vivo mouse model, the pevonedistat treatment significantly prolonged the survival of mice bearing both sensitive and resistant MPM tumors. Pevonedistat treatment reduced growth in sensitive tumors but increased apoptosis in resistant tumors. The mechanism in the resistant tumor model may be mediated by reduced macrophage infiltration, resulting from the suppression of macrophage chemotactic cytokines, C-C motif chemokine ligand 2 (CCL2), expression in tumor cells.
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7
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Abstract
Cullin-RING ligase 4 (CRL4), a member of the cullin-RING ligase family, orchestrates a variety of critical cellular processes and pathophysiological events. Recent results from mouse genetics, clinical analyses, and biochemical studies have revealed the impact of CRL4 in development and cancer etiology and elucidated its in-depth mechanism on catalysis of ubiquitination as a ubiquitin E3 ligase. Here, we summarize the versatile roles of the CRL4 E3 ligase complexes in tumorigenesis dependent on the evidence obtained from knockout and transgenic mouse models as well as biochemical and pathological studies.
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8
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Cheng J, Guo J, North BJ, Tao K, Zhou P, Wei W. The emerging role for Cullin 4 family of E3 ligases in tumorigenesis. Biochim Biophys Acta Rev Cancer 2018; 1871:138-159. [PMID: 30602127 DOI: 10.1016/j.bbcan.2018.11.007] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2018] [Revised: 11/28/2018] [Accepted: 11/29/2018] [Indexed: 02/06/2023]
Abstract
As a member of the Cullin-RING ligase family, Cullin-RING ligase 4 (CRL4) has drawn much attention due to its broad regulatory roles under physiological and pathological conditions, especially in neoplastic events. Based on evidence from knockout and transgenic mouse models, human clinical data, and biochemical interactions, we summarize the distinct roles of the CRL4 E3 ligase complexes in tumorigenesis, which appears to be tissue- and context-dependent. Notably, targeting CRL4 has recently emerged as a noval anti-cancer strategy, including thalidomide and its derivatives that bind to the substrate recognition receptor cereblon (CRBN), and anticancer sulfonamides that target DCAF15 to suppress the neoplastic proliferation of multiple myeloma and colorectal cancers, respectively. To this end, PROTACs have been developed as a group of engineered bi-functional chemical glues that induce the ubiquitination-mediated degradation of substrates via recruiting E3 ligases, such as CRL4 (CRBN) and CRL2 (pVHL). We summarize the recent major advances in the CRL4 research field towards understanding its involvement in tumorigenesis and further discuss its clinical implications. The anti-tumor effects using the PROTAC approach to target the degradation of undruggable targets are also highlighted.
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Affiliation(s)
- Ji Cheng
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China; Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Jianping Guo
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Brian J North
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Kaixiong Tao
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Pengbo Zhou
- Department of Pathology and Laboratory Medicine, Weill Cornell Medicine, 1300 York Ave., New York, NY 10065, USA.
| | - Wenyi Wei
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA.
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9
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Integrative analysis of multi-omics data reveals distinct impacts of DDB1-CUL4 associated factors in human lung adenocarcinomas. Sci Rep 2017; 7:333. [PMID: 28336923 PMCID: PMC5428704 DOI: 10.1038/s41598-017-00512-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 02/28/2017] [Indexed: 12/22/2022] Open
Abstract
Many DDB1-CUL4 associated factors (DCAFs) have been identified and serve as substrate receptors. Although the oncogenic role of CUL4A has been well established, specific DCAFs involved in cancer development remain largely unknown. Here we infer the potential impact of 19 well-defined DCAFs in human lung adenocarcinomas (LuADCs) using integrative omics analyses, and discover that mRNA levels of DTL, DCAF4, 12 and 13 are consistently elevated whereas VBRBP is reduced in LuADCs compared to normal lung tissues. The transcriptional levels of DCAFs are significantly correlated with their gene copy number variations. SKIP2, DTL, DCAF6, 7, 8, 13 and 17 are frequently gained whereas VPRBP, PHIP, DCAF10, 12 and 15 are frequently lost. We find that only transcriptional level of DTL is robustly, significantly and negatively correlated with overall survival across independent datasets. Moreover, DTL-correlated genes are enriched in cell cycle and DNA repair pathways. We also identified that the levels of 25 proteins were significantly associated with DTL overexpression in LuADCs, which include significant decreases in protein level of the tumor supressor genes such as PDCD4, NKX2-1 and PRKAA1. Our results suggest that different CUL4-DCAF axis plays the distinct roles in LuADC development with possible relevance for therapeutic target development.
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10
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Loss of CUL4A expression is underlying cisplatin hypersensitivity in colorectal carcinoma cells with acquired trabectedin resistance. Br J Cancer 2017; 116:489-500. [PMID: 28095394 PMCID: PMC5318979 DOI: 10.1038/bjc.2016.449] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Revised: 12/05/2016] [Accepted: 12/15/2016] [Indexed: 12/12/2022] Open
Abstract
Background: Colorectal carcinoma (CRC) is the third most common cancer worldwide. Platinum-based anticancer compounds still constitute one mainstay of systemic CRC treatment despite limitations due to adverse effects and resistance development. Trabectedin has shown promising antitumor effects in CRC, however, again resistance development may occur. In this study, we aimed to develop strategies to circumvent or even exploit acquired trabectedin resistance in novel CRC treatment regimens. Methods: Human HCT116 CRC cells were selected for acquired trabectedin resistance in vitro and characterised by cell biological as well as bioinformatic approaches. In vivo xenograft experiments were conducted. Results: Selection of HCT116 cells for trabectedin resistance resulted in p53-independent hypersensitivity of the selected subline against cisplatin. Bioinformatic analyses of mRNA microarray data suggested deregulation of nucleotide excision repair and particularly loss of the ubiquitin ligase CUL4A in trabectedin-selected cells. Indeed, transient knockdown of CUL4A sensitised parental HCT116 cells towards cisplatin. Trabectedin selected but not parental HCT116 xenografts were significantly responsive towards cisplatin treatment. Conclusions: Trabectedin selection-mediated CUL4A loss generates an Achilles heel in CRC cancer cells enabling effective cisplatin treatment. Hence, inclusion of trabectedin in cisplatin-containing cancer treatment regimens might cause profound synergism based on reciprocal resistance prevention.
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11
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Deng J, Lei W, Xiang X, Zhang L, Lei J, Gong Y, Song M, Wang Y, Fang Z, Yu F, Feng M, Sun Z, Chen J, Zhan Z, Xiong J. Cullin 4A (CUL4A), a direct target of miR-9 and miR-137, promotes gastric cancer proliferation and invasion by regulating the Hippo signaling pathway. Oncotarget 2017; 7:10037-50. [PMID: 26840256 PMCID: PMC4891102 DOI: 10.18632/oncotarget.7048] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2015] [Accepted: 12/07/2015] [Indexed: 02/07/2023] Open
Abstract
Although Cullin 4A (CUL4A) is mutated or amplified in several human cancer types, its role in gastric cancer (GC) and the mechanisms underlying its regulation remain largely uncharacterized. In the present study, we report that the expression of CUL4A significantly correlated with the clinical stage of the tumor and lymph node metastasis, and survival rates were lower in GC patients with higher levels of CUL4A than in patients with lower CUL4A levels. The upregulation of CUL4A promoted GC cell proliferation and epithelial-mesenchymal transition (EMT) by downregulating LATS1-Hippo-YAP signaling. Knocking down CUL4A had the opposite effect in vitro and in vivo. Interestingly, CUL4A expression was inhibited by the microRNAs (miRNAs), miR-9 and miR-137, which directly targeted the 3′-UTR of CUL4A. Overexpression of miR-9 and miR-137 downregulated the CUL4A-LATS1-Hippo signaling pathway and suppressed GC cell proliferation and invasion in vitro. Taken together, our findings demonstrate that perturbations to miR-9/137-CUL4A-Hippo signaling contribute to gastric tumorigenesis, and suggest potential therapeutic targets for the future treatment of GC.
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Affiliation(s)
- Jun Deng
- Department of Oncology, The First Affiliated Hospital of Nanchang University, Nanchang 330006, PR China
| | - Wan Lei
- Department of Oncology, The First Affiliated Hospital of Nanchang University, Nanchang 330006, PR China
| | - Xiaojun Xiang
- Department of Oncology, The First Affiliated Hospital of Nanchang University, Nanchang 330006, PR China
| | - Ling Zhang
- Department of Oncology, The First Affiliated Hospital of Nanchang University, Nanchang 330006, PR China
| | - Jun Lei
- Department of Oncology, The First Affiliated Hospital of Nanchang University, Nanchang 330006, PR China
| | - Yu Gong
- Department of Oncology, The First Affiliated Hospital of Nanchang University, Nanchang 330006, PR China
| | - Meijiao Song
- Department of Oncology, The First Affiliated Hospital of Nanchang University, Nanchang 330006, PR China
| | - Yi Wang
- Department of Oncology, The First Affiliated Hospital of Nanchang University, Nanchang 330006, PR China
| | - Ziling Fang
- Department of Oncology, The First Affiliated Hospital of Nanchang University, Nanchang 330006, PR China
| | - Feng Yu
- Department of Oncology, The First Affiliated Hospital of Nanchang University, Nanchang 330006, PR China
| | - Miao Feng
- Department of Oncology, The First Affiliated Hospital of Nanchang University, Nanchang 330006, PR China
| | - Ze Sun
- Department of Oncology, The First Affiliated Hospital of Nanchang University, Nanchang 330006, PR China
| | - Jun Chen
- Department of Oncology, The First Affiliated Hospital of Nanchang University, Nanchang 330006, PR China
| | - Zhengyu Zhan
- Department of Oncology, The First Affiliated Hospital of Nanchang University, Nanchang 330006, PR China
| | - Jianping Xiong
- Department of Oncology, The First Affiliated Hospital of Nanchang University, Nanchang 330006, PR China
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12
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Hung MS, Chen IC, You L, Jablons DM, Li YC, Mao JH, Xu Z, Lung JH, Yang CT, Liu ST. Knockdown of cullin 4A inhibits growth and increases chemosensitivity in lung cancer cells. J Cell Mol Med 2016; 20:1295-306. [PMID: 26969027 PMCID: PMC4929302 DOI: 10.1111/jcmm.12811] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 01/15/2016] [Indexed: 12/31/2022] Open
Abstract
Cullin 4A (Cul4A) has been observed to be overexpressed in various cancers. In this study, the role of Cul4A in the growth and chemosensitivity in lung cancer cells were studied. We showed that Cul4A is overexpressed in lung cancer cells and tissues. Knockdown of the Cul4A expression by shRNA in lung cancer cells resulted in decreased cellular proliferation and growth in lung cancer cells. Increased sensitivity to gemcitabine, a chemotherapy drug, was also noted in those Cul4A knockdown lung cancer cells. Moreover, increased expression of p21, transforming growth factor (TGF)-β inducible early gene-1 (TIEG1) and TGF beta-induced (TGFBI) was observed in lung cancer cells after Cul4A knockdown, which may be partially related to increased chemosensitivity to gemcitabine. G0/G1 cell cycle arrest was also noted after Cul4A knockdown. Notably, decreased tumour growth and increased chemosensitivity to gemcitabine were also noted after Cul4A knockdown in lung cancer xenograft nude mice models. In summary, our study showed that targeting Cul4A with RNAi or other techniques may provide a possible insight to the development of lung cancer therapy in the future.
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Affiliation(s)
- Ming-Szu Hung
- Division of Thoracic Oncology, Department of Pulmonary and Critical Care Medicine, Chang Gung Memorial Hospital, Chiayi, Taiwan.,Department of Medicine, College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Department of Respiratory Care, Chang Gung University of Science and Technology, Chiayi, Taiwan
| | - I-Chuan Chen
- Department of Emergency Medicine, Chang Gung Memorial Hospital, Chiayi, Taiwan.,Department of Nursing, Chang Gung University of Science and Technology, Chiayi, Taiwan
| | - Liang You
- Thoracic Oncology Laboratory, Department of Surgery, Comprehensive Cancer Center, University of California, San Francisco, CA, USA
| | - David M Jablons
- Thoracic Oncology Laboratory, Department of Surgery, Comprehensive Cancer Center, University of California, San Francisco, CA, USA
| | - Ya-Chin Li
- Division of Thoracic Oncology, Department of Pulmonary and Critical Care Medicine, Chang Gung Memorial Hospital, Chiayi, Taiwan
| | - Jian-Hua Mao
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Zhidong Xu
- Thoracic Oncology Laboratory, Department of Surgery, Comprehensive Cancer Center, University of California, San Francisco, CA, USA
| | - Jr-Hau Lung
- Department of Medical Research and Development, Chang Gung Memorial Hospital, Chiayi, Taiwan
| | - Cheng-Ta Yang
- Department of Respiratory Care, College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Department of Pulmonary and Critical Care Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Shih-Tung Liu
- Department of Microbiology and Immunology, College of Medicine, Chang Gung University, Taoyuan, Taiwan
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13
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Leung AWY, Hung SS, Backstrom I, Ricaurte D, Kwok B, Poon S, McKinney S, Segovia R, Rawji J, Qadir MA, Aparicio S, Stirling PC, Steidl C, Bally MB. Combined Use of Gene Expression Modeling and siRNA Screening Identifies Genes and Pathways Which Enhance the Activity of Cisplatin When Added at No Effect Levels to Non-Small Cell Lung Cancer Cells In Vitro. PLoS One 2016; 11:e0150675. [PMID: 26938915 PMCID: PMC4777418 DOI: 10.1371/journal.pone.0150675] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 02/16/2016] [Indexed: 01/22/2023] Open
Abstract
Platinum-based combination chemotherapy is the standard treatment for advanced non-small cell lung cancer (NSCLC). While cisplatin is effective, its use is not curative and resistance often emerges. As a consequence of microenvironmental heterogeneity, many tumour cells are exposed to sub-lethal doses of cisplatin. Further, genomic heterogeneity and unique tumor cell sub-populations with reduced sensitivities to cisplatin play a role in its effectiveness within a site of tumor growth. Being exposed to sub-lethal doses will induce changes in gene expression that contribute to the tumour cell’s ability to survive and eventually contribute to the selective pressures leading to cisplatin resistance. Such changes in gene expression, therefore, may contribute to cytoprotective mechanisms. Here, we report on studies designed to uncover how tumour cells respond to sub-lethal doses of cisplatin. A microarray study revealed changes in gene expressions that occurred when A549 cells were exposed to a no-observed-effect level (NOEL) of cisplatin (e.g. the IC10). These data were integrated with results from a genome-wide siRNA screen looking for novel therapeutic targets that when inhibited transformed a NOEL of cisplatin into one that induced significant increases in lethality. Pathway analyses were performed to identify pathways that could be targeted to enhance cisplatin activity. We found that over 100 genes were differentially expressed when A549 cells were exposed to a NOEL of cisplatin. Pathways associated with apoptosis and DNA repair were activated. The siRNA screen revealed the importance of the hedgehog, cell cycle regulation, and insulin action pathways in A549 cell survival and response to cisplatin treatment. Results from both datasets suggest that RRM2B, CABYR, ALDH3A1, and FHL2 could be further explored as cisplatin-enhancing gene targets. Finally, pathways involved in repairing double-strand DNA breaks and INO80 chromatin remodeling were enriched in both datasets, warranting further research into combinations of cisplatin and therapeutics targeting these pathways.
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Affiliation(s)
- Ada W. Y. Leung
- Experimental Therapeutics, BC Cancer Research Centre, Vancouver, BC, Canada
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
- * E-mail:
| | - Stacy S. Hung
- Centre for Lymphoid Cancers, BC Cancer Agency, Vancouver, BC, Canada
| | - Ian Backstrom
- Experimental Therapeutics, BC Cancer Research Centre, Vancouver, BC, Canada
| | - Daniel Ricaurte
- Experimental Therapeutics, BC Cancer Research Centre, Vancouver, BC, Canada
| | - Brian Kwok
- Experimental Therapeutics, BC Cancer Research Centre, Vancouver, BC, Canada
| | - Steven Poon
- Molecular Oncology, BC Cancer Research Centre, Vancouver, BC, Canada
| | - Steven McKinney
- Molecular Oncology, BC Cancer Research Centre, Vancouver, BC, Canada
| | - Romulo Segovia
- Terry Fox Laboratory, BC Cancer Agency, Vancouver, BC, Canada
| | - Jenna Rawji
- Experimental Therapeutics, BC Cancer Research Centre, Vancouver, BC, Canada
| | - Mohammed A. Qadir
- Experimental Therapeutics, BC Cancer Research Centre, Vancouver, BC, Canada
| | - Samuel Aparicio
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
- Molecular Oncology, BC Cancer Research Centre, Vancouver, BC, Canada
| | | | - Christian Steidl
- Centre for Lymphoid Cancers, BC Cancer Agency, Vancouver, BC, Canada
| | - Marcel B. Bally
- Experimental Therapeutics, BC Cancer Research Centre, Vancouver, BC, Canada
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
- Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, BC, Canada
- Centre for Drug Research and Development, Vancouver, BC, Canada
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14
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Wang Y, Xu Z, Mao JH, Hsieh D, Au A, Jablons DM, Li H, You L. PR-Set7 is Degraded in a Conditional Cul4A Transgenic Mouse Model of Lung Cancer. ZHONGGUO FEI AI ZA ZHI = CHINESE JOURNAL OF LUNG CANCER 2016; 18:345-50. [PMID: 26104890 PMCID: PMC5999902 DOI: 10.3779/j.issn.1009-3419.2015.06.15] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Background and objective Maintenance of genomic integrity is essential to ensure normal organismal development and to prevent diseases such as cancer. PR-Set7 (also known as Set8) is a cell cycle regulated enzyme that catalyses monomethylation of histone 4 at Lys20 (H4K20me1) to promote chromosome condensation and prevent DNA damage. Recent studies show that CRL4CDT2-mediated ubiquitylation of PR-Set7 leads to its degradation during S phase and afer DNA damage. Tis might occur to ensure appropriate changes in chromosome structure during the cell cycle or to preserve genome integrity afer DNA damage. Methods We developed a new model of lung tumor development in mice harboring a conditionally expressed allele of Cul4A. We have therefore used a mouse model to demonstrate for the frst time that Cul4A is oncogenic in vivo. With this model, staining of PR-Set7 in the preneoplastic and tumor lesions in AdenoCre-induced mouse lungs was performed. Meanwhile we identifed higher protein level changes of γ-tubulin and pericentrin by IHC. Results Te level of PR-Set7 down-regulated in the preneoplastic and adenocarcinomous lesions following over-expression of Cul4A. We also identifed higher levels of the proteins pericentrin and γ-tubulin in Cul4A mouse lungs induced by AdenoCre. Conclusion PR-Set7 is a direct target of Cul4A for degradation and involved in the formation of lung tumors in the conditional Cul4A transgenic mouse model.
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Affiliation(s)
- Yang Wang
- Thoracic Surgery Department, Beijing Chao-Yang Hospital, Capital University of Medical Science, Beijing 100020, China
| | - Zhidong Xu
- Thoracic Oncology Laboratory, Department of Surgery, Comprehensive Cancer Center, University of California, San Francisco, CA 94143, USA
| | - Jian-Hua Mao
- Life Sciences Division, Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720, USA
| | - David Hsieh
- Thoracic Oncology Laboratory, Department of Surgery, Comprehensive Cancer Center, University of California, San Francisco, CA 94143, USA
| | - Alfred Au
- Division of Diagnostic Pathology, Comprehensive Cancer Center, University of California, San Francisco, CA 94143, USA
| | - David M Jablons
- Thoracic Oncology Laboratory, Department of Surgery, Comprehensive Cancer Center, University of California, San Francisco, CA 94143, USA
| | - Hui Li
- Thoracic Surgery Department, Beijing Chao-Yang Hospital, Capital University of Medical Science, Beijing 100020, China
| | - Liang You
- Thoracic Oncology Laboratory, Department of Surgery, Comprehensive Cancer Center, University of California, San Francisco, CA 94143, USA
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15
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HUNG MINGSZU, CHEN ICHUAN, YOU LIANG, JABLONS DAVIDM, LI YACHIN, MAO JIANHUA, XU ZHIDONG, HSIEH MENGJER, LIN YUCHING, YANG CHENGTA, LIU SHIHTUNG, TSAI YINGHUANG. Knockdown of Cul4A increases chemosensitivity to gemcitabine through upregulation of TGFBI in lung cancer cells. Oncol Rep 2015; 34:3187-95. [DOI: 10.3892/or.2015.4324] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2015] [Accepted: 08/11/2015] [Indexed: 11/06/2022] Open
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16
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Hannah J, Zhou P. Distinct and overlapping functions of the cullin E3 ligase scaffolding proteins CUL4A and CUL4B. Gene 2015; 573:33-45. [PMID: 26344709 DOI: 10.1016/j.gene.2015.08.064] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Revised: 08/03/2015] [Accepted: 08/27/2015] [Indexed: 01/29/2023]
Abstract
The cullin 4 subfamily of genes includes CUL4A and CUL4B, which share a mostly identical amino acid sequence aside from the elongated N-terminal region in CUL4B. Both act as scaffolding proteins for modular cullin RING ligase 4 (CRL4) complexes which promote the ubiquitination of a variety of substrates. CRL4 function is vital to cells as loss of both genes or their shared substrate adaptor protein DDB1 halts proliferation and eventually leads to cell death. Due to their high structural similarity, CUL4A and CUL4B share a substantial overlap in function. However, in some cases, differences in subcellular localization, spatiotemporal expression patterns and stress-inducibility preclude functional compensation. In this review, we highlight the most essential functions of the CUL4 genes in: DNA repair and replication, chromatin-remodeling, cell cycle regulation, embryogenesis, hematopoiesis and spermatogenesis. CUL4 genes are also clinically relevant as dysregulation can contribute to the onset of cancer and CRL4 complexes are often hijacked by certain viruses to promote viral replication and survival. Also, mutations in CUL4B have been implicated in a subset of patients suffering from syndromic X-linked intellectual disability (AKA mental retardation). Interestingly, the antitumor effects of immunomodulatory drugs are caused by their binding to the CRL4CRBN complex and re-directing the E3 ligase towards the Ikaros transcription factors IKZF1 and IKZF3. Because of their influence over key cellular functions and relevance to human disease, CRL4s are considered promising targets for therapeutic intervention.
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Affiliation(s)
- Jeffrey Hannah
- Department of Pathology, Weill Cornell Medical College, 1300 York Ave. NY, NY 10065, United States.
| | - Pengbo Zhou
- Department of Pathology, Weill Cornell Medical College, 1300 York Ave. NY, NY 10065, United States.
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17
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Yang YL, Ni J, Hsu PC, Mao JH, Hsieh D, Xu A, Chan G, Au A, Xu Z, Jablons DM, You L. Cul4A overexpression associated with Gli1 expression in malignant pleural mesothelioma. J Cell Mol Med 2015. [PMID: 26218750 PMCID: PMC4594680 DOI: 10.1111/jcmm.12620] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Malignant pleural mesothelioma (mesothelioma) is a highly aggressive cancer without an effective treatment. Cul4A, a scaffold protein that recruits substrates for degradation, is amplified in several human cancers, including mesothelioma. We have recently shown that Cul4A plays an oncogenic role in vitro and in a mouse model. In this study, we analysed clinical mesothelioma tumours and found moderate to strong expression of Cul4A in 70.9% (51/72) of these tumours, as shown by immunohistochemistry. In 72.2% mesothelioma tumours with increased Cul4A copy number identified by fluorescence in situ hybridization analysis, Cul4A protein expression was moderate to strong. Similarly, Cul4A was overexpressed and Cul4A copy number was increased in human mesothelioma cell lines. Because Gli1 is highly expressed in human mesothelioma cells, we compared Cul4A and Gli1 expression in mesothelioma tumours and found their expression associated (P < 0.05, chi-square). In mesothelioma cell lines, inhibiting Cul4A by siRNA decreased Gli1 expression, suggesting that Gli1 expression is, at least in part, regulated by Cul4A in mesothelioma cells. Our results suggest a linkage between Cul4A and Gli1 expression in human mesothelioma.
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Affiliation(s)
- Yi-Lin Yang
- Department of Surgery, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA, USA
| | - Jian Ni
- Department of Surgery, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA, USA.,Department of Oncology, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China
| | - Ping-Chih Hsu
- Department of Surgery, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA, USA.,Department of Thoracic Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Jian-Hua Mao
- Life Sciences Division, Lawrence Berkeley National Laboratory, University of California, Berkeley, Berkeley, CA, USA
| | - David Hsieh
- Department of Surgery, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA, USA
| | - Angela Xu
- Department of Surgery, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA, USA
| | - Geraldine Chan
- Department of Surgery, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA, USA
| | - Alfred Au
- Division of Diagnostic Pathology, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA, USA
| | - Zhidong Xu
- Department of Surgery, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA, USA
| | - David M Jablons
- Department of Surgery, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA, USA
| | - Liang You
- Department of Surgery, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA, USA
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18
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Wang Y, Zhang P, Liu Z, Wang Q, Wen M, Wang Y, Yuan H, Mao JH, Wei G. CUL4A overexpression enhances lung tumor growth and sensitizes lung cancer cells to erlotinib via transcriptional regulation of EGFR. Mol Cancer 2014; 13:252. [PMID: 25413624 PMCID: PMC4246448 DOI: 10.1186/1476-4598-13-252] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Accepted: 11/10/2014] [Indexed: 12/21/2022] Open
Abstract
Background CUL4A has been proposed as oncogene in several types of human cancer, but its clinical significance and functional role in human non-small cell lung cancer (NSCLC) remain unclear. Methods Expression level of CUL4A was examined by RT-PCR and Western blot. Forced expression of CUL4A was mediated by retroviruses, and CUL4A silencing by shRNAs expressing lentiviruses. Growth capacity of lung cancer cells was measured by MTT in vitro and tumorigenesis in vivo, respectively. Results We found that CUL4A was highly expressed in human lung cancer tissues and lung cancer cell lines, and this elevated expression positively correlated with disease progression and prognosis. Overexpression of CUL4A in human lung cancer cell lines increased cell proliferation, inhibited apoptosis, and subsequently conferred resistance to chemotherapy. On other hand, silencing CUL4A expression in NSCLC cells reduced proliferation, promoted apoptosis and resulted in tumor growth inhibition in cancer xenograft model. Mechanistically, we revealed CUL4A regulated EGFR transcriptional expression and activation, and subsequently activated AKT. Targeted inhibition of EGFR activity blocked these CUL4A induced oncogenic activities. Conclusions Our results highlight the significance of CUL4A in NSCLC and suggest that CUL4A could be a promising therapy target and a potential biomarker for prognosis and EGFR target therapy in NSCLC patients. Electronic supplementary material The online version of this article (doi:10.1186/1476-4598-13-252) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Guangwei Wei
- Department of Anatomy and Key Laboratory of Experimental Teratology, Ministry of Education, Shandong University School of Medicine, 44 Wenhua Xi Road, Jinan, Shandong 250012, P,R, China.
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