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Li R, Yang Y, Lan H, Wang Y, Ge Z, Liu X, Zhou Y, Zhang W, Xian L, Yuan H. A Novel Mechanism of hPRL-G129R, a Prolactin Antagonist, Inhibits Human Breast Cancer Cell Proliferation and Migration. Endocrinology 2023; 164:bqad158. [PMID: 37934803 DOI: 10.1210/endocr/bqad158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 09/06/2023] [Accepted: 11/02/2023] [Indexed: 11/09/2023]
Abstract
Prolactin (PRL) and its receptor, PRLR, are closely related to the occurrence and development of breast cancer. hPRL-G129R, an hPRLR antagonist, has been found to induce apoptosis in breast cancer cells via mechanisms currently unknown. Recent studies have indicated that PRLR exhibits dual functions based on its membrane/nucleus localization. In that context, we speculated whether hPRL-G129R is a dual-function antagonist. We studied the internalization of the hPRLR-G129R/PRLR complex using indirect immunofluorescence and Western blot assays. We found that hPRL-G129R not only inhibited PRLR-mediated intracellular signaling at the plasma membrane, but also blocked nuclear localization of the receptor in T-47D and MCF-7 cells in a time-dependent manner. Clone formation and transwell migration assays showed that hPRL-G129R inhibited PRL-driven proliferation and migration of tumor cells in vitro. Further, we found that increasing concentrations of hPRL-G129R inhibited the nuclear localization of PRLR and the levels of signal transducer and activator of transcription (STAT) 5 in tumor-bearing mice and hPRL-G129R also exerted an antiproliferative effect in vivo. These results indicate that hPRL-G129R is indeed a dual-function antagonist. This study lays a foundation for exploring and developing highly effective agents against the proliferation and progression of breast malignancies.
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Affiliation(s)
- Ruonan Li
- Medicine and Pharmacy Research Center, Binzhou Medical University, Yantai 264003, China
| | - Yu Yang
- Medicine and Pharmacy Research Center, Binzhou Medical University, Yantai 264003, China
- State Key Laboratory of Animal Nutrition, Ministry of Agriculture Key Laboratory of Animal Genetics Breeding and Reproduction, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Hainan Lan
- College of Animal Science and Technology, Jilin Agricultural University, Changchun 130118, China
| | - Yuesi Wang
- Medicine and Pharmacy Research Center, Binzhou Medical University, Yantai 264003, China
| | - Zihan Ge
- Medicine and Pharmacy Research Center, Binzhou Medical University, Yantai 264003, China
| | - Xingjie Liu
- Medicine and Pharmacy Research Center, Binzhou Medical University, Yantai 264003, China
| | - Yixuan Zhou
- Medicine and Pharmacy Research Center, Binzhou Medical University, Yantai 264003, China
| | - Wei Zhang
- Medicine and Pharmacy Research Center, Binzhou Medical University, Yantai 264003, China
| | - Li Xian
- Medicine and Pharmacy Research Center, Binzhou Medical University, Yantai 264003, China
| | - Hongxuan Yuan
- College of Medicine, Yanbian University, Yanji 133002, China
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2
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Abstract
Prolactin coordinates with the ovarian steroids to orchestrate mammary development and lactation, culminating in nourishment and an increasingly appreciated array of other benefits for neonates. Its central activities in mammary epithelial growth and differentiation suggest that it plays a role(s) in breast cancer, but it has been challenging to identify its contributions, essential for incorporation into prevention and treatment approaches. Large prospective epidemiologic studies have linked higher prolactin exposure to increased risk, particularly for ER+ breast cancer in postmenopausal women. However, it has been more difficult to determine its actions and clinical consequences in established tumors. Here we review experimental data implicating multiple mechanisms by which prolactin may increase the risk of breast cancer. We then consider the evidence for role(s) of prolactin and its downstream signaling cascades in disease progression and treatment responses, and discuss how new approaches are beginning to illuminate the biology behind the seemingly conflicting epidemiologic and experimental studies of prolactin actions across diverse breast cancers.
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3
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Menendez JA, Peirce SK, Papadimitropoulou A, Cuyàs E, Steen TV, Verdura S, Vellon L, Chen WY, Lupu R. Progesterone receptor isoform-dependent cross-talk between prolactin and fatty acid synthase in breast cancer. Aging (Albany NY) 2020; 12:24671-24692. [PMID: 33335078 PMCID: PMC7803566 DOI: 10.18632/aging.202289] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 10/27/2020] [Indexed: 04/13/2023]
Abstract
Progesterone receptor (PR) isoforms can drive unique phenotypes in luminal breast cancer (BC). Here, we hypothesized that PR-B and PR-A isoforms differentially modify the cross-talk between prolactin and fatty acid synthase (FASN) in BC. We profiled the responsiveness of the FASN gene promoter to prolactin in T47Dco BC cells constitutively expressing PR-A and PR-B, in the PR-null variant T47D-Y cell line, and in PR-null T47D-Y cells engineered to stably re-express PR-A (T47D-YA) or PR-B (T47D-YB). The capacity of prolactin to up-regulate FASN gene promoter activity in T47Dco cells was lost in T47D-Y and TD47-YA cells. Constitutively up-regulated FASN gene expression in T47-YB cells and its further stimulation by prolactin were both suppressed by the prolactin receptor antagonist hPRL-G129R. The ability of the FASN inhibitor C75 to decrease prolactin secretion was more conspicuous in T47-YB cells. In T47D-Y cells, which secreted notably less prolactin and downregulated prolactin receptor expression relative to T47Dco cells, FASN blockade resulted in an augmented secretion of prolactin and up-regulation of prolactin receptor expression. Our data reveal unforeseen PR-B isoform-specific regulatory actions in the cross-talk between prolactin and FASN signaling in BC. These findings might provide new PR-B/FASN-centered predictive and therapeutic modalities in luminal intrinsic BC subtypes.
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MESH Headings
- 4-Butyrolactone/analogs & derivatives
- 4-Butyrolactone/pharmacology
- Breast Neoplasms/genetics
- Breast Neoplasms/metabolism
- Carcinoma, Ductal, Breast/genetics
- Carcinoma, Ductal, Breast/metabolism
- Cell Line, Tumor
- Databases, Genetic
- Fatty Acid Synthase, Type I/antagonists & inhibitors
- Fatty Acid Synthase, Type I/genetics
- Fatty Acid Synthase, Type I/metabolism
- Humans
- Interleukin-6/metabolism
- Prolactin/metabolism
- Prolactin/pharmacology
- Promoter Regions, Genetic
- Protein Isoforms
- RNA, Messenger/metabolism
- Receptor Cross-Talk
- Receptors, Progesterone/genetics
- Receptors, Progesterone/metabolism
- Receptors, Prolactin/antagonists & inhibitors
- Receptors, Prolactin/genetics
- Receptors, Prolactin/metabolism
- Up-Regulation
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Affiliation(s)
- Javier A. Menendez
- Program Against Cancer Therapeutic Resistance (ProCURE), Metabolism and Cancer Group, Catalan Institute of Oncology, Girona, Spain
- Girona Biomedical Research Institute (IDIBGI), Girona, Spain
| | | | | | - Elisabet Cuyàs
- Program Against Cancer Therapeutic Resistance (ProCURE), Metabolism and Cancer Group, Catalan Institute of Oncology, Girona, Spain
- Girona Biomedical Research Institute (IDIBGI), Girona, Spain
| | - Travis Vander Steen
- Mayo Clinic, Division of Experimental Pathology, Department of Laboratory Medicine and Pathology, Rochester, MN 55905, USA
| | - Sara Verdura
- Program Against Cancer Therapeutic Resistance (ProCURE), Metabolism and Cancer Group, Catalan Institute of Oncology, Girona, Spain
- Girona Biomedical Research Institute (IDIBGI), Girona, Spain
| | - Luciano Vellon
- Stem Cells Laboratory, Institute of Biology and Experimental Medicine (IBYME-CONICET), Buenos Aires, Argentina
| | - Wen Y. Chen
- Department of Biological Sciences, Clemson University, Greenville, SC 29634, USA
| | - Ruth Lupu
- Mayo Clinic, Division of Experimental Pathology, Department of Laboratory Medicine and Pathology, Rochester, MN 55905, USA
- Mayo Clinic Minnesota, Department of Biochemistry and Molecular Biology Laboratory, Rochester, MN 55905, USA
- Mayo Clinic Cancer Center, Rochester, MN 55905, USA
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4
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Xu X, Yuan X, Ni J, Guo J, Gao Y, Yin W, Li F, Wei L, Zhang J. MAGI2-AS3 inhibits breast cancer by downregulating DNA methylation of MAGI2. J Cell Physiol 2020; 236:1116-1130. [PMID: 32730644 DOI: 10.1002/jcp.29922] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Accepted: 06/19/2020] [Indexed: 12/30/2022]
Abstract
Breast cancer is one of the most threatening diseases for women. Long noncoding RNAs were reported to be involved in breast cancer development. In this study, we analyzed The Cancer Genome Atlas breast cancer tissue high-throughput sequencing data and screened and validated the low-expressing long noncoding RNA named MAGI2-AS3. Through gene coexpression analysis, we found that MAGI2-AS3 has a good expression correlation with MAGI2. Overexpression of MAGI2-AS3 or MAGI2 in breast cancer cells MCF-7 would inhibit the Wnt/β-catenin pathway and inhibit cell proliferation and migration. Gene structure and DNA methylation analysis results indicated that MAGI2-AS3 may act as a cis-acting regulatory element downregulating the DNA methylation level of the MAGI2 promoter region, and the DNA demethylase TET1 inhibitor can reverse MAGI2-AS3 overexpression caused upregulation of MAGI2 and cellular effects. Our findings reveal the role of MAGI2-AS3 in breast cancer and provide potential novel therapeutic targets for metastatic breast cancer intervention.
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Affiliation(s)
- Xiaolong Xu
- Department of Pathology and Pathophysiology, Hubei Provincial Key Laboratory of Developmentally Originated Disease, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei, China
| | - Xiaoning Yuan
- Department of Pathology and Pathophysiology, Hubei Provincial Key Laboratory of Developmentally Originated Disease, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei, China
| | - Jiali Ni
- Department of Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Jing Guo
- Department of Genetics, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei, China
| | - Yang Gao
- Department of Pathology and Pathophysiology, Hubei Provincial Key Laboratory of Developmentally Originated Disease, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei, China
| | - Weinan Yin
- Department of Pathology and Pathophysiology, Hubei Provincial Key Laboratory of Developmentally Originated Disease, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei, China
| | - Feng Li
- Department of Genetics, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei, China
| | - Lei Wei
- Department of Pathology and Pathophysiology, Hubei Provincial Key Laboratory of Developmentally Originated Disease, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei, China
| | - Jingwei Zhang
- Department of Breast and Thyroid Surgery, Zhongnan Hospital, Hubei Key Laboratory of Tumor Biological Behaviors, Hubei Cancer Clinical Study Center, Wuhan University, Wuhan, Hubei, China
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5
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Alarcón H, Bonzon-Kulichenko E, Peinado R, Lim F, Vázquez J, Rodríguez A. Generation of a lentiviral vector system to efficiently express bioactive recombinant human prolactin hormones. Mol Cell Endocrinol 2020; 499:110605. [PMID: 31580897 DOI: 10.1016/j.mce.2019.110605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 09/26/2019] [Accepted: 09/29/2019] [Indexed: 10/25/2022]
Abstract
The contribution of the pleiotropic hormone Prolactin (PRL) to several physiological and pathological processes is still unknown. To clarify the role of PRL in these processes during the last decade, different human PRL antagonists have been produced to either partially or fully block the wild type hormone activity. In this work, we have cloned these wild type and antagonist sequences in lentivectors (LV) to express them as recombinant self-processing polypeptides by employing a P2A sequence (hPRL-P2A-GFP). We show that these LVs can efficiently transduce and express the hPRL proteins in different cell types and that the P2A sequence does not affect their activities. Additionally, we have tested their activities in paracrine and autocrine cell culture experiments. Our results demonstrate that these recombinant hPRL-P2A proteins are bioactive in both paracrine and autocrine modes, highlighting the potential usefulness of these hPRL-containing LVs for determining the contribution of hPRL to different biological processes.
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Affiliation(s)
- Hernán Alarcón
- Department of Molecular Biology, Autonomous University of Madrid, Madrid, 28049, Spain
| | - Elena Bonzon-Kulichenko
- Laboratory of Cardiovascular Proteomics, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, 28029, Spain; CIBER de Enfermedades Cardiovasculares (CIBERCV), Madrid, 28029, Spain
| | - Rocío Peinado
- Department of Molecular Biology, Autonomous University of Madrid, Madrid, 28049, Spain
| | - Filip Lim
- Department of Molecular Biology, Autonomous University of Madrid, Madrid, 28049, Spain
| | - Jesús Vázquez
- Laboratory of Cardiovascular Proteomics, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, 28029, Spain; CIBER de Enfermedades Cardiovasculares (CIBERCV), Madrid, 28029, Spain
| | - Antonio Rodríguez
- Department of Molecular Biology, Autonomous University of Madrid, Madrid, 28049, Spain.
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6
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The Effect of Ethanol Baneh Skin Extract on the Expressions of Bcl - 2, Bax, and Caspase - 3 Concentration in Human Prostate Cancer pc3 Cells. INTERNATIONAL JOURNAL OF CANCER MANAGEMENT 2018. [DOI: 10.5812/ijcm.9865] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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7
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Lan H, Hong P, Li R, L S, Anshan S, Li S, Zheng X. Internal image anti-idiotypic antibody: A new strategy for the development a new category of prolactin receptor (PRLR) antagonist. Mol Immunol 2017; 87:86-93. [DOI: 10.1016/j.molimm.2017.04.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Revised: 03/24/2017] [Accepted: 04/05/2017] [Indexed: 10/19/2022]
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8
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Ding K, Yuan Y, Chong QY, Yang Y, Li R, Li X, Kong X, Qian P, Xiong Z, Pandey V, Ma L, Wu Z, Lobie PE, Zhu T. Autocrine Prolactin Stimulates Endometrial Carcinoma Growth and Metastasis and Reduces Sensitivity to Chemotherapy. Endocrinology 2017; 158:1595-1611. [PMID: 28204229 DOI: 10.1210/en.2016-1903] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Accepted: 02/06/2017] [Indexed: 12/29/2022]
Abstract
Advanced and recurrent endometrial carcinoma (EC) exhibits a poor response to chemotherapy and low survival rates. It has been previously reported that human prolactin (hPRL) is upregulated in endometrial cancer and is associated with worse survival outcomes. We provide evidence for the functional role of hPRL in EC progression. We generated a model for the study of autocrine hPRL-mediated cell functional effects through the forced expression of hPRL in human EC cells. Autocrine hPRL expression stimulated cell proliferation, anchorage-independent growth, migration, and invasion of EC cells and promoted tumor growth, local invasion, and metastatic colonization in xenograft models. In addition, forced expression of hPRL decreased sensitivity of EC cells to chemotherapeutic drugs (i.e., doxorubicin and paclitaxel), both in vitro and in vivo. Consistently, small interfering RNA-mediated depletion of hPRL significantly reduced oncogenicity and enhanced the chemosensitivity of EC cells. As CD24 is hPRL-regulated and has been implicated in drug resistance in EC, we further showed that CD24 is a critical mediator of hPRL-stimulated reduced sensitivity to doxorubicin and paclitaxel in EC cells. Therefore, inhibition of hPRL signaling is a potential therapeutic strategy for the treatment of late-stage EC, which can be used in combination with chemotherapy to improve the chemotherapeutic response.
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Affiliation(s)
- Keshuo Ding
- CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China
- Department of Pathology, Anhui Medical University, Hefei, Anhui 230000, China
| | - Yan Yuan
- CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China
- Hefei National Laboratory for Physical Sciences at Microscale, Hefei, Anhui 230027, China
| | - Qing-Yun Chong
- Cancer Science Institute of Singapore and Department of Pharmacology, National University of Singapore, Singapore 117599
| | - Yulu Yang
- CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Rui Li
- CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Xiaoni Li
- CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China
- Hefei National Laboratory for Physical Sciences at Microscale, Hefei, Anhui 230027, China
| | - Xiangjun Kong
- CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China
- Hefei National Laboratory for Physical Sciences at Microscale, Hefei, Anhui 230027, China
| | - Pengxu Qian
- CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China
- Hefei National Laboratory for Physical Sciences at Microscale, Hefei, Anhui 230027, China
| | - Zirui Xiong
- CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Vijay Pandey
- Cancer Science Institute of Singapore and Department of Pharmacology, National University of Singapore, Singapore 117599
| | - Lan Ma
- Tsinghua-Berkeley Shenzhen Institute and Division of Life Sciences and Health, Tsinghua University Graduate School, Shenzhen 518055, China
| | - Zhengsheng Wu
- Department of Pathology, Anhui Medical University, Hefei, Anhui 230000, China
| | - Peter E Lobie
- Cancer Science Institute of Singapore and Department of Pharmacology, National University of Singapore, Singapore 117599
- Tsinghua-Berkeley Shenzhen Institute and Division of Life Sciences and Health, Tsinghua University Graduate School, Shenzhen 518055, China
| | - Tao Zhu
- CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China
- Hefei National Laboratory for Physical Sciences at Microscale, Hefei, Anhui 230027, China
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9
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Kim YJ, Kim HK, Yang DH, Jung S, Noh MG, Lee JH, Lee KH, Moon KS. Pineal Diffuse Large B-Cell Lymphoma Concomitant With Pituitary Prolactinoma: Possible Correlation Between 2 Distinguished Pathologies: A Case Report. Medicine (Baltimore) 2016; 95:e2923. [PMID: 26937937 PMCID: PMC4779034 DOI: 10.1097/md.0000000000002923] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
This is the first reported case of pineal lymphoma with concomitant prolactin-producing pituitary adenoma.A 51-year-old male experienced worsening headaches accompanied by nausea, diplopia, and memory loss for 1 month. Cranial nerve examination revealed bilateral upward gaze limitation with convergence impairment, which is known as Parinaud syndrome. Magnetic resonance images revealed a mass in the pineal gland with a coexisting mass within the enlarged sella fossa. Hormone analysis revealed hyperprolactinemia. The pineal mass was removed without injuring the hypothalamus, brain stem, or any neighboring vessels. Pathology examination confirmed the diagnosis of diffuse large B-cell lymphoma (DLBCL) involving the pineal gland. After further studies, the pineal lymphoma was determined to be a secondary tumor from a gastric primary tumor. The patient died 6 months after diagnosis due to systemic progression of DLBCL.Although the mechanistic link between hyperprolactinemia and lymphoma progression has not been clarified on a clinical basis, high prolactin levels may contribute to the rapid progression and therapeutic resistance of the lymphoma.
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Affiliation(s)
- Yeong-Jin Kim
- From the Department of Neurosurgery (Y-JK, SJ, K-SM); Department of Internal Medicine (HKK, D-HY); and Departments of Pathology, Chonnam National University Research Institute of Medical Sciences (M-GN, J-HL, K-HL), Chonnam National University Hwasun Hospital and Medical School, Hwasun-gun, Jeollanamdo, South Korea
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10
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Abstract
Excessive Ca(2+) entry during glutamate receptor overactivation ("excitotoxicity") induces acute or delayed neuronal death. We report here that deficiency in bax exerted broad neuroprotection against excitotoxic injury and oxygen/glucose deprivation in mouse neocortical neuron cultures and reduced infarct size, necrotic injury, and cerebral edema formation after middle cerebral artery occlusion in mice. Neuronal Ca(2+) and mitochondrial membrane potential (Δψm) analysis during excitotoxic injury revealed that bax-deficient neurons showed significantly reduced Ca(2+) transients during the NMDA excitation period and did not exhibit the deregulation of Δψm that was observed in their wild-type (WT) counterparts. Reintroduction of bax or a bax mutant incapable of proapoptotic oligomerization equally restored neuronal Ca(2+) dynamics during NMDA excitation, suggesting that Bax controlled Ca(2+) signaling independently of its role in apoptosis execution. Quantitative confocal imaging of intracellular ATP or mitochondrial Ca(2+) levels using FRET-based sensors indicated that the effects of bax deficiency on Ca(2+) handling were not due to enhanced cellular bioenergetics or increased Ca(2+) uptake into mitochondria. We also observed that mitochondria isolated from WT or bax-deficient cells similarly underwent Ca(2+)-induced permeability transition. However, when Ca(2+) uptake into the sarco/endoplasmic reticulum was blocked with the Ca(2+)-ATPase inhibitor thapsigargin, bax-deficient neurons showed strongly elevated cytosolic Ca(2+) levels during NMDA excitation, suggesting that the ability of Bax to support dynamic ER Ca(2+) handling is critical for cell death signaling during periods of neuronal overexcitation.
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11
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Prolactin receptor attenuation induces zinc pool redistribution through ZnT2 and decreases invasion in MDA-MB-453 breast cancer cells. Exp Cell Res 2014; 321:190-200. [DOI: 10.1016/j.yexcr.2013.12.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2013] [Revised: 12/01/2013] [Accepted: 12/03/2013] [Indexed: 11/15/2022]
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12
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Koirala S, Thomas LN, Too CKL. Prolactin/Stat5 and androgen R1881 coactivate carboxypeptidase-D gene in breast cancer cells. Mol Endocrinol 2014; 28:331-43. [PMID: 24433040 DOI: 10.1210/me.2013-1202] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Plasma membrane-bound carboxypeptidase-D (CPD) cleaves C-terminal arginine from extracellular substrates. In the cell, arginine is converted to nitric oxide (NO). We have reported that up-regulation of CPD mRNA/protein levels by 17β-estradiol and prolactin (PRL) in breast cancer cells, and by testosterone in prostate cancer cells, increased NO production and cell survival. The CPD promoter contains a consensus γ-interferon-activated sequence (GAS) and 3 putative androgen response elements (ARE.1, ARE.2, ARE.3) that could potentially bind PRL-activated transcription factor Stat5 (signal transducer and activator of transcription 5) and the liganded androgen receptor (AR), respectively. This study showed that synthetic androgen R1881 and PRL elevated CPD mRNA/protein levels in human MCF-7 and T47D breast cancer cells in a time-/dose-dependent manner. PRL/R1881-elevated CPD expression was blocked by actinomycin-D, and a CPD promoter construct containing these GAS and AREs was stimulated by PRL or R1881, indicating transcriptional regulation by both hormones. Luciferase reporter assays showed that GAS and the adjacent ARE.1 only were active. Mutation of GAS in the ΔGAS-CPD construct (ARE.1 intact) abolished CPD promoter activity in response to PRL and, surprisingly, to R1881 as well. ΔGAS-CPD promoter activity was restored by PRL+R1881 in combination, and enhanced by ectopic Stat5, but abolished by Stat5 gene knockdown. Chromatin immunoprecipitation analysis confirmed binding of activated Stat5 and liganded AR to GAS and ARE.1, respectively. Activated Stat5 also induced binding of unliganded AR to ARE.1, and liganded AR induced binding of unactivated Stat5 to GAS. In summary, PRL and R1881, acting through Stat5 and AR, act cooperatively to stimulate CPD gene transcription in breast cancer cells.
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Affiliation(s)
- Samir Koirala
- Department of Biochemistry & Molecular Biology (S.K., L.N.T., C.K.L.T.) and Department of Obstetrics & Gynaecology (C.K.L.T.), Faculty of Medicine, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
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13
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Reevaluation of the proposed autocrine proliferative function of prolactin in breast cancer. Breast Cancer Res Treat 2013; 142:31-44. [PMID: 24146212 PMCID: PMC3825490 DOI: 10.1007/s10549-013-2731-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Accepted: 10/08/2013] [Indexed: 11/08/2022]
Abstract
The pituitary hormone prolactin (PRL) has been implicated in tumourigenesis. Expression of PRL and its receptor (PRLR) was reported in human breast epithelium and breast cancer cells. It was suggested that PRL may act as an autocrine/paracrine growth factor. Here, we addressed the role of locally synthesised PRL in breast cancer. We analysed the expression of PRL in human breast cancer tumours using qPCR analysis and in situ hybridization (ISH). PRL mRNA expression was very low or undetectable in the majority of samples in three cDNA arrays representing samples from 144 breast cancer patients and in 13 of 14 breast cancer cell lines when analysed by qPCR. In accordance, PRL expression did not reach detectable levels in any of the 19 human breast carcinomas or 5 cell lines, which were analysed using a validated ISH protocol. Two T47D-derived breast cancer cell lines were stably transfected with PRL-expressing constructs. Conditioned medium from the T47D/PRL clones promoted proliferation of lactogen-dependent Nb2 cells and control T47D cells. Surprisingly, the PRL-producing clones themselves displayed a lower proliferation rate as compared to the control cells. Their PRLR protein level was reduced and the cells were no longer responsive to exogenous recombinant PRL. Taken together, these data strongly indicate that autocrine PRL signalling is unlikely to be a general mechanism promoting tumour growth in breast cancer patients.
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14
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Damiano JS, Wasserman E. Molecular pathways: blockade of the PRLR signaling pathway as a novel antihormonal approach for the treatment of breast and prostate cancer. Clin Cancer Res 2013; 19:1644-50. [PMID: 23515410 DOI: 10.1158/1078-0432.ccr-12-0138] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The prolactin (PRL)-prolactin receptor (PRLR) signaling complex has been implicated in the pathology of breast and prostate carcinoma. A multitude of pro-oncogenic intracellular signaling pathways are activated by PRL in breast and prostate epithelial cells, leading to enhanced cellular proliferation, survival, and tumorigenesis in numerous model systems. Emerging evidence suggests that targeting the PRL-PRLR axis in human cancer may represent an unexploited avenue for therapeutic intervention and, given the extensive cross-talk between PRLR and other signal transduction pathways, a potential means through which other anticancer agents could be rendered more efficacious in the clinic. LFA102 is a potent anti-PRLR neutralizing antibody that efficiently abrogates the function of this receptor in vivo, mediating significant antitumor effects in preclinical models. The clean safety profile of this antibody in animals and in the clinical experiences to date suggests that blocking the PRLR signaling pathway in human tumors may have few significant toxicologic consequences and may be a promising approach to treating cancer. A phase I trial in patients with breast and prostate cancer is underway to better understand the clinical utility of LFA102 and the contribution of PRL to the maintenance and progression of human cancer.
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Affiliation(s)
- Jason S Damiano
- Novartis Institutes for BioMedical Research, Emeryville, CA 94608, USA.
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15
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Herranz M, Pombo M, Menendez-Rodriguez P, Arias JI, Ruibal A. Breast carcinomas with hyperprolactinemia at the time of diagnosis-clinico-biological association. Gynecol Endocrinol 2012; 28:278-81. [PMID: 22420628 DOI: 10.3109/09513590.2011.631631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
AIM To analyse association between preoperative hyperprolactinemia serum levels and clinical and biological features of breast tumors. METHODS Serum levels of prolactin were measured in 253 women with invasive breast cancer. Clinical and biological parameters analysed were age, size, lymph node involvement, distant metastasis and immunohistochemical expression of estrogen receptor, progesterone receptor, androgen receptor, bcl-2, p53 and Ki67. RESULTS In ductal carcinomas hyperprolactinemia were associated with high age (p = 0.017), and with bcl-2 + + + expression (p = 0.017). Furthermore, serum prolactin values were significantly higher in bcl-2 +++ cases vs negative (p = 0.029); the same happened when we considered the positivity threshold of 25 ng/mL (p = 0.015). CONCLUSION Is possible to detect in 6% of infiltrating ductal breast carcinomas hyperprolactinemia (>25 ng/mL), being associated only with increasing age, but not with other clinical or biological factors; and 2) the most surprising data was the association between prolactinemia (qualitative (>25 ng/mL) and quantitative) and intense bcl-2 tissue expression, which suggests that, probably, this (prolactinemia) is not a sign of worse prognosis and evolution.
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MESH Headings
- Age Factors
- Aged
- Aged, 80 and over
- Biomarkers, Tumor/blood
- Biomarkers, Tumor/metabolism
- Breast Neoplasms/blood
- Breast Neoplasms/complications
- Breast Neoplasms/diagnosis
- Carcinoma, Ductal, Breast/blood
- Carcinoma, Ductal, Breast/complications
- Carcinoma, Ductal, Breast/diagnosis
- Female
- Humans
- Hyperprolactinemia/blood
- Hyperprolactinemia/complications
- Middle Aged
- Prognosis
- Prolactin/blood
- Proto-Oncogene Proteins c-bcl-2/metabolism
- Receptors, Androgen/metabolism
- Receptors, Estrogen/metabolism
- Receptors, Progesterone/metabolism
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Affiliation(s)
- M Herranz
- Molecular Oncology and Imaging Program, Complejo Hospitalario Universitario, Santiago de Compostela, A Coruña, Spain.
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16
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Tan D, Chen KE, Khoo T, Walker AM. Prolactin increases survival and migration of ovarian cancer cells: Importance of prolactin receptor type and therapeutic potential of S179D and G129R receptor antagonists. Cancer Lett 2011; 310:101-8. [DOI: 10.1016/j.canlet.2011.06.014] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2011] [Revised: 06/03/2011] [Accepted: 06/12/2011] [Indexed: 11/29/2022]
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17
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Idelman G, Jacobson EM, Tuttle TR, Ben-Jonathan N. Lactogens and estrogens in breast cancer chemoresistance. Expert Rev Endocrinol Metab 2011; 6:411-422. [PMID: 21731573 PMCID: PMC3125604 DOI: 10.1586/eem.11.19] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Tumor resistance to chemotherapy in advanced breast cancer is a major impediment to treatment success. Resistance can be induced by the drugs themselves or result from the action of internal factors. The role of hormones in chemoresistance has received little attention. This article focuses on two classes of hormones: lactogens and estrogens. Lactogens include prolactin, growth hormone and placental lactogen, all of which can activate the prolactin receptor. Estrogens include endogenous steroids and nonsteroidal compounds from the environment termed endocrine disruptors, all of which can activate 'classical' estrogen receptors (ERα and ERβ), as well as other types of receptors. Both lactogens and estrogens antagonize cytotoxicity of multiple chemotherapeutic agents through complementary mechanisms. The implications of chemoresistance by these hormones to patients with breast cancer, and the potential benefits of developing combinatorial anti-lactogen/anti-estrogen treatment regimens, are discussed.
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Affiliation(s)
- Gila Idelman
- Department of Cancer and Cell Biology, University of Cincinnati, 7315 Eden Avenue, Cincinnati, OH 45267-0521, USA
| | - Eric M Jacobson
- Department of Cancer and Cell Biology, University of Cincinnati, 7315 Eden Avenue, Cincinnati, OH 45267-0521, USA
| | - Traci R Tuttle
- Department of Cancer and Cell Biology, University of Cincinnati, 7315 Eden Avenue, Cincinnati, OH 45267-0521, USA
| | - Nira Ben-Jonathan
- Department of Cancer and Cell Biology, University of Cincinnati, 7315 Eden Avenue, Cincinnati, OH 45267-0521, USA
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18
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Hwang J, Na S, Lee H, Lee D. Correlation between preoperative serum levels of five biomarkers and relationships between these biomarkers and cancer stage in epithelial overian cancer. J Gynecol Oncol 2009; 20:169-75. [PMID: 19809551 DOI: 10.3802/jgo.2009.20.3.169] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2009] [Revised: 08/25/2009] [Accepted: 08/26/2009] [Indexed: 11/30/2022] Open
Abstract
OBJECTIVE To examine the correlation among the preoperative serum levels of five biomarkers presumed to be useful for early detection of epithelial ovarian cancer and evaluate the relationships between serum levels of these five biomarkers and epithelial ovarian cancer stage. METHODS We analyzed 56 newly diagnosed epithelial ovarian cancer patients. Preoperative serum levels of leptin, prolactin, osteopontin (OPN), insulin-like growth factor-II, and CA-125 were determined by ELISA. We also examined the correlation between the serum levels of the biomarkers and ovarian cancer stage. Significant differences in the mean serum levels of two proteins, leptin and CA-125, were observed between stage subsets. RESULTS There was a significant negative correlation between prolactin and leptin and a significant positive correlation between prolactin and OPN. Of the five biomarkers, only the mean serum CA-125 level showed a significant positive correlation with cancer stage (Spearman rho=0.24, p<0.01). OPN showed a marginally significant positive correlation with stage (Spearman rho=0.14, p=0.07). CONCLUSION We demonstrated the relationship between five biomarkers in epithelial ovarian cancer. These tumor markers may be useful in screening for ovarian cancer, in characterizing disease states, and in developing therapeutic interventions targeting these marker proteins. Large-scale studies that include potential confounding factors and modifiers are necessary to more accurately define the value of these novel biomarkers in ovarian cancer.
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Affiliation(s)
- Jongyun Hwang
- Department of Obstetrics and Gynecology, Kangwon National University Medical School, Chuncheon, Korea
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19
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Prolactin and the Skin: A Dermatological Perspective on an Ancient Pleiotropic Peptide Hormone. J Invest Dermatol 2009; 129:1071-87. [DOI: 10.1038/jid.2008.348] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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20
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Structure and function of a new class of human prolactin antagonists. Protein Expr Purif 2009; 66:121-30. [PMID: 19236917 DOI: 10.1016/j.pep.2009.02.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2008] [Revised: 02/10/2009] [Accepted: 02/11/2009] [Indexed: 11/21/2022]
Abstract
Delta 41-52 hPRL (human prolactin with residues 41-52 removed) is a lead compound for a new class of hPRL antagonists. The deleted sequence contains residues that functionally couple sites 1 and 2, the two hormone surfaces that each bind receptors. Delta 41-52 hPRL retains 0.03% agonist activity in FDC-1 cell bioassays, a 3054-fold reduction in activity, and displays approximately 100-fold less agonist activity than G129R hPRL, an antagonist that reduces the binding of hPRL receptor at site 2 during the formation of the heterotrimeric hormone/receptor complex. Replacement of various numbers and types of residues into the gap created by the deletion of residues 41 through 52 created hPRLs with varying agonist activities, suggested that manipulation of the sequence connecting the C-terminal of helix 1 with the disulfide bond (cysteines 58 with 174) linking helices 1 and 4 modulates articulation of these helices and influences agonist activity. We have compared the antagonist activities of G129R and Delta 41-52 hPRLs to induce apoptosis in Jurkat cells, a human lymphoid cell line displaying an autocrine/paracrine hPRL/receptor system. Delta 41-52 hPRL induces apoptosis in a time and dose-dependent fashion. Under these same conditions G129R hPRL fails to induce apoptosis. We conclude Delta 41-52 hPRL is a lead compound of a new class of hPRL antagonists capable at low concentrations of inducing apoptosis in human cells expressing an autocrine/paracrine hPRL/receptor system.
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21
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Nguyen N, Zhu Y. Prolactin functions as a survival factor during zebrafish embryogenesis. Comp Biochem Physiol A Mol Integr Physiol 2008; 153:88-93. [PMID: 19032987 DOI: 10.1016/j.cbpa.2008.10.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2008] [Revised: 10/20/2008] [Accepted: 10/22/2008] [Indexed: 10/21/2022]
Abstract
Prolactin is a multifaceted hormone that is capable of modulating hundreds of physiological processes in adult vertebrates. However, the physiological functions of prolactin in embryonic development are still controversial. One of these biological functions of prolactin is to promote survival of the cells. Almost all studies on the anti-apoptotic action of prolactin have been focused on a variety of mammalian cell lines and tissues, while no study has been reported on prolactin's anti-apoptotic role in the embryo. In order to determine whether prolactin acts as a survival factor for embryonic cells during development, prolactin protein was knocked-down in zebrafish embryos by microinjection of prolactin-morpholino antisense (PRL-MO). Significant increase in the number of apoptotic cells was observed in embryos treated with PRL-MO compared to control embryos injected with control morpholino or non-injected controls. The number of apoptotic cells increased more significantly between 15 and 35 h post-fertilization in the PRL-MO treated group than that of the control. Interestingly, apoptotic cells were restricted to the central nervous system, particularly in the eyes and brain. Apoptosis of these cells was further demonstrated using the comet assay to detect DNA damage, a hallmark of apoptosis. It was found that the level of DNA damage was dose-dependent on the concentration of PRL-MO injected and consistent with higher levels of nick ends detected by the TUNEL assay in PRL-MO embryos. Further examination of apoptotic genes indicated the transcript of caspase-8, a representative caspase gene of the extrinsic pathway, was much higher in prolactin knockdown embryos than the non-injected control. Together, these results suggest that prolactin acts as a survival factor during zebrafish embryogenesis.
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Affiliation(s)
- Nhu Nguyen
- Department of Biology, East Carolina University, Greenville, NC 27858, USA
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22
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Howell SJ, Anderson E, Hunter T, Farnie G, Clarke RB. Prolactin receptor antagonism reduces the clonogenic capacity of breast cancer cells and potentiates doxorubicin and paclitaxel cytotoxicity. Breast Cancer Res 2008; 10:R68. [PMID: 18681966 PMCID: PMC2575541 DOI: 10.1186/bcr2129] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2008] [Revised: 07/14/2008] [Accepted: 08/05/2008] [Indexed: 11/26/2022] Open
Abstract
Introduction Exogenous prolactin is mitogenic and antiapoptotic in breast cancer cells, and overexpression of autocrine prolactin cDNA in breast cancer cell lines has been shown to stimulate their growth and to protect against chemotherapy-induced apoptosis. We examined the effects of the 'pure' prolactin receptor antagonist Δ1–9-G129R-hPrl (Δ1–9) on the breast cancer cell number and clonogenicity, alone and in combination with chemotherapy. Methods The effects of doxorubicin, paclitaxel and Δ1–9 on the growth of breast cancer cell lines (MCF-7, T47D, MDA-MB-453, MDA-MB-468 and SK-BR-3) in monolayer culture were assessed by the sulphorhodamine B assay. Effects on clonogenicity were assessed by soft agar assay for the cell lines and by the mammosphere assay for disaggregated primary ductal carcinoma in situ samples. Dual-fluorescence immunocytochemistry was used to identify subpopulations of cells expressing the prolactin receptor and autocrine prolactin. Results Δ1–9 as a single agent had no effect on the cell number in monolayer culture, but potentiated the cytotoxic effects of doxorubicin and paclitaxel. Doxorubicin accordingly induced expression of prolactin mRNA and protein in all five breast cancer cell lines tested. Δ1–9 alone inhibited the clonogenicity in soft agar of cell lines by ~90% and the mammosphere forming efficiency of six disaggregated primary ductal carcinoma in situ samples by a median of 56% (range 32% to 88%). Subpopulations of cells could be identified in the cell lines based on the prolactin receptor and prolactin expression. Conclusion Autocrine prolactin appears to act as an inducible survival factor in a clonogenic subpopulation of breast cancer cells. The rational combination of cytotoxics and Δ1–9 may therefore improve outcomes in breast cancer therapy by targeting this cell population.
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Affiliation(s)
- Sacha J Howell
- Breast Biology Group, Paterson Institute for Cancer Research, University of Manchester, Wilmslow Road, Manchester M20 4BX, UK.
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23
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Clevenger CV, Zheng J, Jablonski EM, Galbaugh TL, Fang F. From bench to bedside: future potential for the translation of prolactin inhibitors as breast cancer therapeutics. J Mammary Gland Biol Neoplasia 2008; 13:147-56. [PMID: 18246318 DOI: 10.1007/s10911-008-9074-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2008] [Accepted: 01/04/2008] [Indexed: 11/30/2022] Open
Abstract
A role for prolactin (PRL) in the pathogenesis of breast cancer has been confirmed at the cellular level in vitro, with multiple transgenic and knockout models in vivo, and within sizable patient populations through epidemiologic analysis. It is the obvious "next step" that these findings are translated into meaningful therapies to block PRL/PRLr function in human breast cancer. Several broad categories of PRL/PRLr antagonists are discussed in their pre-clinical context, including inhibitors of endocrine PRL elaboration, mutant ligand antagonists, ligand chimeras, and inhibitors of PRL-induced signaling and transactivation. The clinical potential for GHr antagonists are also discussed. These varied approaches all have demonstrated as proof-of-principle that PRL/PRLr antagonism can inhibit the in vitro and in vivo growth of breast cancer. Further pre-clinical development is required for most, however, before translation to clinical trials in breast cancer patients can occur.
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Affiliation(s)
- Charles V Clevenger
- Diana, Princess of Wales Professor of Cancer Research, Robert H. Lurie Comprehensive Cancer Center, Department of Pathology, Northwestern University, Chicago, IL 60611, USA.
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24
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Tallet E, Rouet V, Jomain JB, Kelly PA, Bernichtein S, Goffin V. Rational design of competitive prolactin/growth hormone receptor antagonists. J Mammary Gland Biol Neoplasia 2008; 13:105-17. [PMID: 18219565 DOI: 10.1007/s10911-008-9066-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2007] [Accepted: 01/02/2008] [Indexed: 01/22/2023] Open
Abstract
There is increasing evidence that prolactin (PRL) and growth hormone (GH) act as growth-promoters of breast tumors. Recent arguments have accumulated to suggest that when they are locally-produced within the mammary tissue, these hormones, acting by an autocrine-paracrine mechanism may have enhanced, or even specific functions compared to endocrine PRL and GH. Classical drugs blocking pituitary hormone production (dopamine and somatostatin analogs) are ineffective on extrapituitary expression of PRL/GH genes, therefore the undesirable effects of these locally-produced hormones remain a target of interest for alternative strategies. This has encouraged the development of competitive PRL and/or GH receptor antagonists, which involve engineered variants of natural receptor ligands (PRL or GH) aimed at blocking receptor activation rather than hormone production in peripheral tissues. This article overviews the rational design of this new class of molecules, their specific molecular features (receptor specificity, biological properties, etc.) and whenever available, the data that have been obtained in cell or animal models of breast cancer.
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Affiliation(s)
- Estelle Tallet
- Inserm, U845, Centre de Recherche Croissance et signalisation, Equipe PRL, GH et tumeurs, Paris, 75015, France
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25
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Inhibition of cell proliferation by siRNA targeting hPRLR in breast cancer MCF-7 cell line. ACTA ACUST UNITED AC 2007. [DOI: 10.1016/s1007-4376(07)60081-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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26
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Additive effects of a prolactin receptor antagonist, G129R, and herceptin on inhibition of HER2-overexpressing breast cancer cells. Breast Cancer Res Treat 2007; 111:241-50. [DOI: 10.1007/s10549-007-9789-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2007] [Accepted: 10/08/2007] [Indexed: 10/22/2022]
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27
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Walker AM. Therapeutic potential of S179D prolactin – from prostate cancer to angioproliferative disorders: the first selective prolactin receptor modulator. Expert Opin Investig Drugs 2006; 15:1257-67. [PMID: 16989600 DOI: 10.1517/13543784.15.10.1257] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Increasing evidence suggests an important role for autocrine/paracrine prolactin in breast and prostate cancers and other disease states. Prolactin production in these extrapituitary sites is not governed by dopamine agonists, a finding that has spurred the production of prolactin receptor antagonists. This review focuses on one such antagonist, S179D prolactin, which was produced by mimicking a natural antagonist, phosphorylated prolactin. S179D prolactin is a very effective growth antagonist, partly because it inhibits signalling from unmodified prolactin and partly because it produces its own intracellular signal. This signal results in cell differentiation, cell-cycle arrest or apoptosis depending on dose, duration of treatment and cellular context. S179D prolactin is also a potent antiangiogenic and initial studies have shown it to be a potent anti-inflammatory agent. In light of these additional modes of action, it is suggested that S179D prolactin should now be more aptly referred to as a selective prolactin receptor modulator.
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Affiliation(s)
- Ameae M Walker
- University of California, Division of Biomedical Sciences, Riverside, CA 92521, USA.
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28
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Soares CRJ, Glezer A, Okazaki K, Ueda EKM, Heller SR, Walker AM, Goffin V, Bartolini P. Physico-chemical and biological characterizations of two human prolactin analogs exhibiting controversial bioactivity, synthesized in Chinese hamster ovary (CHO) cells. Protein Expr Purif 2006; 48:182-94. [PMID: 16814566 DOI: 10.1016/j.pep.2006.04.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2005] [Revised: 04/20/2006] [Accepted: 04/20/2006] [Indexed: 10/24/2022]
Abstract
The synthesis, purification and characterization of G129R-hPRL and S179D-hPRL, the two better-studied antagonists of human prolactin (hPRL), is described. Both of these have been expressed for the first time, in their authentic form, by a stable CHO cell line, at secretion levels of 7.7 and 4.3 microg/10(6) cells/day, respectively. Previous studies had shown that these hPRL analogs, when produced in bacterial cytoplasm, consistently contained misfolded forms and multimers according to the specific denaturation, refolding and purification conditions. These versions also have an N-terminal extra methionine. An extensive physico-chemical characterization was carried out after a practical two-step purification process and included SDS-PAGE and Western blotting analysis, matrix-assisted laser-desorption ionization time-of-flight mass spectral (MALDI-TOF-MS) analysis, high-performance size-exclusion chromatography (HPSEC) and reversed-phase high-performance liquid chromatography (RP-HPLC). This last technique revealed a considerable difference in hydrophobicity due to a single amino acid substitution, with S179D-hPRL less (t(RR) = 0.85 +/- 0.010) and G129R-hPRL more (t(RR) = 1.10 +/- 0.013) hydrophobic than hPRL, where t(RR) is the relative retention time. The biological characterization was based on further refinement of a sensitive proliferation assay using the pro-B murine cell line (Ba/F3) transfected with the long form hPRL receptor cDNA such that the minimal detectable dose was 0.04 ng of hPRL/mL, the Ba/F3-LLP assay. On the basis of this assay, the relative residual agonistic activity of these two products, determined against a hPRL international standard in four independent assays, was 53 x 10(-3) for S179D-hPRL and 70 x 10(-5) for G129R-hPRL. We believe that the present synthesis and characterization could be extremely helpful for studies of these two proteins, which have been reported to antagonize tumor growth-promoting effects of hPRL in vivo in animal models of breast and prostate cancer.
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Affiliation(s)
- C R J Soares
- Biotechnology Department, National Nuclear Energy Commission-IPEN-CNEN, Cidade Universitária, São Paulo, Brazil
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29
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Govoni KE, Lee SK, Chadwick RB, Yu H, Kasukawa Y, Baylink DJ, Mohan S. Whole genome microarray analysis of growth hormone-induced gene expression in bone: T-box3, a novel transcription factor, regulates osteoblast proliferation. Am J Physiol Endocrinol Metab 2006; 291:E128-36. [PMID: 16464905 PMCID: PMC3000614 DOI: 10.1152/ajpendo.00592.2005] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Growth hormone (GH) is important in the development and maintenance of bone; however, the IGF-dependent and -independent molecular pathways involved remain to be established. We used microarray analysis to evaluate GH signaling pathways in 4-wk-old GH-deficient mice following a single injection of GH (4 mg/kg body wt) or PBS (n = 6/group) at 6 or 24 h after treatment. Six thousand one hundred sixty genes were differentially expressed at P </= 0.05, and 17% of these genes were identified at both time points. Several of the genes differentially expressed were expressed sequence tags, and the remaining genes fell into 49 Gene Ontology categories. For subsequent studies, we focused on T-box (Tbx)3, a novel transcription factor, which increased more than twofold at both time points. Real-time RT-PCR analysis determined that pretreatment with IGF-binding protein-4 did not block GH-induced Tbx3 expression in vitro. Pretreatment with TNF-alpha blocked GH-induced Tbx3 expression. Tbx3 expression increased during osteoblast differentiation and following BMP-7 and Wnt3a treatment (P </= 0.05). Blocking Tbx3 expression by small interfering RNA decreased cell number and [(3)H]Thymidine incorporation (P < 0.01). In conclusion, 1) GH caused acute changes in several novel genes, suggesting that many GH-induced signaling pathways and target genes remain to be discovered; 2) because Tbx3 expression is regulated in osteoblasts and blockage of Tbx3 expression decreased cell number and DNA synthesis, we propose that Tbx3 is an important determinant of osteoblast cell number.
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Affiliation(s)
- Kristen E Govoni
- Musculoskeletal Disease Center (151 Jerry L. Pettis Memorial Veterans Affairs Medical Center, 11201 Benton St., Loma Linda, CA 92357, USA
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30
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Dong J, Tsai-Morris CH, Dufau ML. A novel estradiol/estrogen receptor alpha-dependent transcriptional mechanism controls expression of the human prolactin receptor. J Biol Chem 2006; 281:18825-36. [PMID: 16651265 DOI: 10.1074/jbc.m512826200] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Prolactin exerts diverse functions in target tissues through its membrane receptors, and is a potent mitogen in normal and neoplastic breast cells. Estradiol (E(2)) induces human prolactin receptor (hPRLR) gene expression through stimulation of its generic promoter (PIII). This study identifies a novel E(2)-regulated non-estrogen responsive element-dependent transcriptional mechanism that mediates E(2)-induced hPRLR expression. E(2) stimulated transcriptional activity in MCF7A(2) cells transfected with PIII lacking an estrogen responsive element, and increased hPRLR mRNA and protein. The abolition of the E(2) effect by mutation of Sp1 or C/EBP elements that bind Sp1/Sp3 and C/EBPbeta within PIII indicated the cooperation of these transfactors in E(2)-induced transcription of the hPRLR. DNA affinity protein assay showed that E(2) induced estrogen receptor alpha (ERalpha) binding to Sp1/Sp3 and C/EBPbeta DNA-protein complexes. The ligand-binding domain of ERalpha was essential for its physical interaction with C/EBPbeta, and E(2) promoted this association, and its DNA binding domain was required for transactivation of PIII. Co-immunoprecipitation studies revealed tethering of C/EBPbeta to Sp1 by E(2)-activated ERalpha. Chromatin immunoprecipitation analysis showed that E(2) induced recruitment of C/EBPbeta, ERalpha, SRC1, p300, pCAF, TFIIB, and Pol II, with no change in Sp1/Sp3. E(2) also induced promoter-associated acetylation of H3 and H4. These findings demonstrate that an E(2)/ERalpha, Sp1, and C/EBPbeta complex with recruitment of coactivators and TFIIB and Pol II are required for E(2)-activated transcriptional expression of the hPRLR through PIII. Estradiol produced in breast stroma and adipose tissue, which are major sources of estrogen in post-menopausal women, could up-regulate hPRLR gene expression and stimulate breast tumor growth.
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Affiliation(s)
- Juying Dong
- Section on Molecular Endocrinology, Endocrinology and Reproduction Research Branch, NICHD, National Institutes of Health, Bethesda, Maryland 20892, USA
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31
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Foitzik K, Krause K, Conrad F, Nakamura M, Funk W, Paus R. Human scalp hair follicles are both a target and a source of prolactin, which serves as an autocrine and/or paracrine promoter of apoptosis-driven hair follicle regression. THE AMERICAN JOURNAL OF PATHOLOGY 2006; 168:748-56. [PMID: 16507890 PMCID: PMC1606541 DOI: 10.2353/ajpath.2006.050468] [Citation(s) in RCA: 104] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The prototypic pituitary hormone prolactin (PRL) exerts a wide variety of bioregulatory effects in mammals and is also found in extrapituitary sites, including murine skin. Here, we show by reverse transcriptase-polymerase chain reaction and immunohistology that, contrary to a previous report, human skin and normal human scalp hair follicles (HFs), in particular, express both PRL and PRL receptors (PRL-R) at the mRNA and protein level. PRL and PRL-R immunoreactivity can be detected in the epithelium of human anagen VI HFs, while the HF mesenchyme is negative. During the HF transformation from growth (anagen) to apoptosis-driven regression (catagen), PRL and PRL-R immunoreactivity appear up-regulated. Treatment of organ-cultured human scalp HFs with high-dose PRL (400 ng/ml) results in a significant inhibition of hair shaft elongation and premature catagen development, along with reduced proliferation and increased apoptosis of hair bulb keratinocytes (Ki-67/terminal dUTP nick-end labeling immunohistomorphometry). This shows that PRL receptors, expressed in HFs, are functional and that human skin and human scalp HFs are both direct targets and sources of PRL. Our data suggest that PRL acts as an autocrine hair growth modulator with catagen-promoting functions and that the hair growth-inhibitory effects of PRL demonstrated here may underlie the as yet ill-understood hair loss in patients with hyper-prolactinemia.
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Affiliation(s)
- Kerstin Foitzik
- Department of Dermatology, University Hospital Hamburg-Eppendorf, University of Hamburg, Hamburg, Germany.
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32
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Langenheim JF, Chen WY. Development of a prolactin receptor-targeting fusion toxin using a prolactin antagonist and a recombinant form of Pseudomonas exotoxin A. Breast Cancer Res Treat 2005; 90:281-93. [PMID: 15830142 PMCID: PMC1398053 DOI: 10.1007/s10549-004-4816-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Human prolactin (hPRL) promotes the proliferation and differentiation of mammary epithelial cells during mammary gland development and has been linked to breast tumor development. The receptor for hPRL (hPRL-R) is elevated in a majority of human breast tumors, suggesting the overexpression of hPRL-R makes cancer cells highly sensitive to the mitogenic and anti-apoptotic activity of hPRL. These findings provide the rationale for the development of hPRL-R targeting breast cancer therapeutics. Previously, an hPRL-R antagonist, G129R, was developed that competitively binds to the hPRL-R resulting in growth inhibition and the induction of apoptosis in certain types of breast cancer cells. To further increase the potency of G129R, we fused G129R to a truncated form of Pseudomonas exotoxin A (PE(40)) that lacks the cell recognition domain of the toxin but retains the domains necessary for PE(40)_ to translocate into the cytosol and inhibit protein synthesis. We postulated that the fusion of G129R with PE(40)-KDEL would (1) deliver the recombinant toxin to breast cancer cells where hPRL-R is overexpressed; (2) block hPRL signaling via its G129R moiety; and (3) inhibit protein synthesis via its PE(40)-KDEL moiety. We demonstrate that the fusion toxin can competitively bind to hPRL-Rs on T-47D human breast cancer cells and inhibit STAT5 phosphorylation induced by hPRL. In addition, we show that G129R-PE(40)-KDEL is selectively cytotoxic to breast cancer cell lines expressing the hPRL-R and that cell death is associated with the inhibition of protein synthesis and does not involve caspase mediated apoptosis.
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Affiliation(s)
- John F Langenheim
- Department of Biological Sciences, Clemson University, Clemson, SC, USA
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Goffin V, Bernichtein S, Touraine P, Kelly PA. Development and potential clinical uses of human prolactin receptor antagonists. Endocr Rev 2005; 26:400-22. [PMID: 15814850 DOI: 10.1210/er.2004-0016] [Citation(s) in RCA: 150] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
There is a large body of literature showing that prolactin (PRL) exerts growth-promoting activities in breast cancer, and possibly in prostate cancer and prostate hyperplasia. In addition, increasing evidence argues for the involvement of locally produced (autocrine) PRL, perhaps even more than pituitary-secreted (endocrine) PRL, in tumor growth. Because dopamine analogs are unable to inhibit PRL production in extrapituitary sites, alternative strategies need investigation. To that end, several PRL receptor antagonists have been developed by introducing various mutations into its natural ligands. For all but one of these analogs, the mechanism of action involves a competition with endogenous PRL for receptor binding. Such compounds are thus candidates to counteract the undesired actions of PRL, not only in tumors, but also in dopamine-resistant prolactinomas. In this review, we describe the different versions of antagonists that have been developed, with emphasis on the controversies regarding their characterization, and the limits for their potential development as a drug. The most recently developed antagonist, Delta1-9-G129R-hPRL, is the only one that is totally devoid of residual agonistic activity, meaning it acts as pure antagonist. We discuss to what extent this new molecule could be considered as a lead compound for inhibiting the actions of human PRL in the above-mentioned diseases. We also speculate on the multiple questions that could be addressed with respect to the therapeutic use of PRL receptor antagonists in patients.
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Affiliation(s)
- Vincent Goffin
- Institut National de la Santé et de la Recherche Médicale Unit 584, Faculté de Médecine Necker, 156, rue de Vaugirard, 75730 Paris Cedex 15, France.
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