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Choi WS, Liu RZ, Mak C, Maadi H, Godbout R. Overcoming retinoic acid resistance in HER2-enriched breast cancers: role of MYC. FEBS J 2024. [PMID: 38708519 DOI: 10.1111/febs.17151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 02/12/2024] [Accepted: 04/18/2024] [Indexed: 05/07/2024]
Abstract
HER2-enriched (HER2+) breast cancers express high levels of the growth-promoting HER2 protein. Although these cancers are treated with the HER2-targeted drug, trastuzumab, resistance to treatment is common. Retinoic acid (RA) is an anti-cancer agent that has been successfully used for the treatment of leukemia and holds promise for the treatment of solid cancers, including breast cancer. The HER2 gene is frequently co-amplified with RARA, a key determinant of RA sensitivity in breast cancers. It seems surprising, therefore, that HER2+ breast cancers are refractory to RA treatment. Here, we show that MYC mediates RA resistance by suppressing the expression of cellular retinoic acid binding protein 2 (CRABP2), resulting in RARα inactivation. CRABP2 is an intracellular RA transporter that delivers RA to the nuclear receptor RARα for its activation. Our results indicate that response to RA is enhanced by MYC depletion in HER2+ breast cancer cells and that RA treatment enhances trastuzumab responsiveness. Our findings support the use of RA and trastuzumab for the treatment of subsets of patients with breast cancers that are HER2-RARα co-amplified and have low levels of MYC.
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Affiliation(s)
- Won-Shik Choi
- Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, Canada
| | - Rong-Zong Liu
- Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, Canada
| | - Caitlin Mak
- Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, Canada
| | - Hamid Maadi
- Department of Cell and Molecular Biology & Microbiology, Faculty of Biological Science and Technology, University of Isfahan, Iran
| | - Roseline Godbout
- Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, Canada
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2
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Koh VCY, Ng CCY, Bay BH, Teh BT, Tan PH. The utility of a targeted gene mutation panel in refining the diagnosis of breast phyllodes tumours. Pathology 2019; 51:531-534. [PMID: 31272781 DOI: 10.1016/j.pathol.2019.04.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 04/08/2019] [Indexed: 12/30/2022]
Affiliation(s)
- Valerie Cui Yun Koh
- Department of Anatomical Pathology, Singapore General Hospital, Singapore; Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | | | - Boon Huat Bay
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Bin Tean Teh
- Laboratory of Cancer Epigenome, National Cancer Centre Singapore, Singapore; Duke-NUS Medical School, Singapore
| | - Puay Hoon Tan
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Duke-NUS Medical School, Singapore; Division of Pathology, Singapore General Hospital, Singapore.
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3
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Nagaprashantha LD, Singhal J, Chikara S, Gugiu G, Horne D, Awasthi S, Salgia R, Singhal SS. 2′-Hydroxyflavanone induced changes in the proteomic profile of breast cancer cells. J Proteomics 2019; 192:233-245. [DOI: 10.1016/j.jprot.2018.09.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 09/03/2018] [Accepted: 09/10/2018] [Indexed: 12/12/2022]
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4
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Zhang Y, Li P, Pan H, Liu L, Ji M, Sheng N, Wang C, Cai L, Ma Y. Retinal-conjugated pH-sensitive micelles induce tumor senescence for boosting breast cancer chemotherapy. Biomaterials 2016; 83:219-32. [PMID: 26774567 DOI: 10.1016/j.biomaterials.2016.01.023] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Revised: 01/04/2016] [Accepted: 01/04/2016] [Indexed: 01/09/2023]
Abstract
Evoking tumor cellular senescence, an irreversible status of cell growth quiescence, has been recently proposed as a potential strategy to improve the efficacy of cancer treatment. In the current study, all-trans retinal, the precursor of all-trans retinoic acid, was conjugated to dextran via hydrazone bond to generate amphiphilic dextran-retinal (DR) conjugates, which self-assembled into pH-sensitive DR micelles. Our results showed that DR micelles moderately inhibited MCF-7 breast cancer cell growth through inducing p21-associated cellular senescence, which relied on retinoic acid receptors (RARs) and was accompanied by significant G0/G1 cell cycle arrest. Moreover, DR micelles were capable of encapsulating doxorubicin (DOX) to generate DOX-loaded DD micelles, facilitating the uptake and release of DOX in cancer cells. Compared with free DOX, DD micelles more effectively suppressed tumor growth and prolonged survival time of mouse xenograft model through inducing tumor apoptosis and cellular senescence. However, blocking cellular senescence diminished DD-caused apoptosis in MCF-7 cells by 40-50%. Therefore, pH-sensitive DR micelles not only served as a potent platform for DOX delivery, but also enhanced the anti-tumor effect of DOX by inducing tumor cellular senescence. These data reveal a great potential of evoking tumor senescence with retinal-conjugated micelles for boosting breast cancer chemotherapy.
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Affiliation(s)
- Yijuan Zhang
- Key Lab of Health Informatics of Chinese Academy of Sciences, Guangdong Key Laboratory of Nanomedicine, Shenzhen Laboratory of Fully Human Antibody Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Science, Shenzhen 518055, PR China
| | - Ping Li
- Key Lab of Health Informatics of Chinese Academy of Sciences, Guangdong Key Laboratory of Nanomedicine, Shenzhen Laboratory of Fully Human Antibody Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Science, Shenzhen 518055, PR China
| | - Hong Pan
- Key Lab of Health Informatics of Chinese Academy of Sciences, Guangdong Key Laboratory of Nanomedicine, Shenzhen Laboratory of Fully Human Antibody Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Science, Shenzhen 518055, PR China
| | - Lanlan Liu
- Key Lab of Health Informatics of Chinese Academy of Sciences, Guangdong Key Laboratory of Nanomedicine, Shenzhen Laboratory of Fully Human Antibody Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Science, Shenzhen 518055, PR China
| | - Manyi Ji
- Key Lab of Health Informatics of Chinese Academy of Sciences, Guangdong Key Laboratory of Nanomedicine, Shenzhen Laboratory of Fully Human Antibody Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Science, Shenzhen 518055, PR China
| | - Nan Sheng
- Key Lab of Health Informatics of Chinese Academy of Sciences, Guangdong Key Laboratory of Nanomedicine, Shenzhen Laboratory of Fully Human Antibody Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Science, Shenzhen 518055, PR China
| | - Ce Wang
- Key Lab of Health Informatics of Chinese Academy of Sciences, Guangdong Key Laboratory of Nanomedicine, Shenzhen Laboratory of Fully Human Antibody Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Science, Shenzhen 518055, PR China
| | - Lintao Cai
- Key Lab of Health Informatics of Chinese Academy of Sciences, Guangdong Key Laboratory of Nanomedicine, Shenzhen Laboratory of Fully Human Antibody Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Science, Shenzhen 518055, PR China
| | - Yifan Ma
- Key Lab of Health Informatics of Chinese Academy of Sciences, Guangdong Key Laboratory of Nanomedicine, Shenzhen Laboratory of Fully Human Antibody Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Science, Shenzhen 518055, PR China.
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5
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Cao Y, Wei W, Zhang N, Yu Q, Xu WB, Yu WJ, Chen GQ, Wu YL, Yan H. Oridonin stabilizes retinoic acid receptor alpha through ROS-activated NF-κB signaling. BMC Cancer 2015; 15:248. [PMID: 25886043 PMCID: PMC4403721 DOI: 10.1186/s12885-015-1219-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Accepted: 03/19/2015] [Indexed: 12/22/2022] Open
Abstract
Background Retinoic acid receptor alpha (RARα) plays an essential role in the regulation of many biological processes, such as hematopoietic cell differentiation, while abnormal RARα function contributes to the pathogenesis of certain diseases including cancers, especially acute promyelocytic leukemia (APL). Recently, oridonin, a natural diterpenoid isolated from Rabdosia rubescens, was demonstrated to regulate RARα by increasing its protein level. However, the underlying molecular mechanism for this action has not been fully elucidated. Methods In the APL cell line, NB4, the effect of oridonin on RARα protein was analyzed by western blot and real-time quantitative RT-PCR analyses. Flow cytometry was performed to detect intracellular levels of reactive oxygen species (ROS). The association between nuclear factor-kappa B (NF-κB) signaling and the effect of oridonin was assessed using specific inhibitors, shRNA gene knockdown, and immunofluorescence assays. In addition, primary leukemia cells were treated with oridonin and analyzed by western blot in this study. Results RARα possesses transcriptional activity in the presence of its ligand, all-trans retinoic acid (ATRA). Oridonin remarkably stabilized the RARα protein, which retained transcriptional activity. Oridonin also moderately increased intracellular ROS levels, while pretreatment with the ROS scavenger, N-acetyl-l-cysteine (NAC), dramatically abrogated RARα stabilization by oridonin. More intriguingly, direct exposure to low concentrations of H2O2 also increased RARα protein but not mRNA levels, suggesting a role for ROS in oridonin stabilization of RARα protein. Further investigations showed that NAC antagonized oridonin-induced activation of NF-κB signaling, while the NF-κB signaling inhibitor, Bay 11–7082, effectively blocked the oridonin increase in RARα protein levels. In line with this, over-expression of IκΒα (A32/36), a super-repressor form of IκΒα, or NF-κB-p65 knockdown inhibited oridonin or H2O2-induced RARα stability. Finally, tumor necrosis factor alpha (TNFα), a classical activator of NF-κB signaling, modulated the stability of RARα protein. Conclusions Oridonin stabilizes RARα protein by increasing cellular ROS levels, which causes activation of the NF-κB signaling pathway.
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Affiliation(s)
- Yang Cao
- Department of Hematology, Rui-Jin Hospital, Shanghai Jiao-Tong University School of Medicine, Shanghai, China.
| | - Wei Wei
- Department of Hematology, Xinhua Hospital, Shanghai Jiao-Tong University School of Medicine, Shanghai, China.
| | - Nan Zhang
- Department of Hematology, Rui-Jin Hospital, Shanghai Jiao-Tong University School of Medicine, Shanghai, China.
| | - Qing Yu
- Department of Hematology, Rui-Jin Hospital, Shanghai Jiao-Tong University School of Medicine, Shanghai, China.
| | - Wen-Bin Xu
- Department of Hematology, Rui-Jin Hospital, Shanghai Jiao-Tong University School of Medicine, Shanghai, China.
| | - Wen-Jun Yu
- Department of Hematology, Rui-Jin Hospital, Shanghai Jiao-Tong University School of Medicine, Shanghai, China.
| | - Guo-Qiang Chen
- Department of Pathophysiology, Chemical Biology Division of Shanghai Universities E-Institutes, Key Laboratory of Cell Differentiation and Apoptosis of National Ministry of Education, Shanghai Jiao-Tong University School of Medicine, Shanghai, China.
| | - Ying-Li Wu
- Department of Pathophysiology, Chemical Biology Division of Shanghai Universities E-Institutes, Key Laboratory of Cell Differentiation and Apoptosis of National Ministry of Education, Shanghai Jiao-Tong University School of Medicine, Shanghai, China.
| | - Hua Yan
- Department of Hematology, Rui-Jin Hospital, Shanghai Jiao-Tong University School of Medicine, Shanghai, China.
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Ribeiro MPC, Santos AE, Custódio JBA. Interplay between estrogen and retinoid signaling in breast cancer--current and future perspectives. Cancer Lett 2014; 353:17-24. [PMID: 25042865 DOI: 10.1016/j.canlet.2014.07.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2014] [Revised: 06/17/2014] [Accepted: 07/08/2014] [Indexed: 01/11/2023]
Abstract
All-trans-retinoic acid (RA) is a promising agent for breast cancer treatment, but it induces several adverse effects and the few clinical trials performed up to now in breast cancer patients have provided disappointing results. The combination of RA and antiestrogenic compounds, such as tamoxifen, synergistically decreases the proliferation of breast cancer cells and an interplay between retinoid and estrogen signaling has begun to be unraveled, turning these combinations into an appealing strategy for breast cancer treatment. This review focus on the current knowledge regarding the interplay between retinoid and estrogen signaling in breast cancer and the combinations of RA with antiestrogens, aiming their future utilization in cancer therapy.
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Affiliation(s)
- Mariana P C Ribeiro
- Center for Neuroscience and Cell Biology, University of Coimbra, 3000-354 Coimbra, Portugal; Laboratory of Biochemistry, Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal.
| | - Armanda E Santos
- Center for Neuroscience and Cell Biology, University of Coimbra, 3000-354 Coimbra, Portugal; Laboratory of Biochemistry, Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal
| | - José B A Custódio
- Center for Neuroscience and Cell Biology, University of Coimbra, 3000-354 Coimbra, Portugal; Laboratory of Biochemistry, Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal
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7
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Hao R, Bondesson M, Singh AV, Riu A, McCollum CW, Knudsen TB, Gorelick DA, Gustafsson JÅ. Identification of estrogen target genes during zebrafish embryonic development through transcriptomic analysis. PLoS One 2013; 8:e79020. [PMID: 24223173 PMCID: PMC3819264 DOI: 10.1371/journal.pone.0079020] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Accepted: 09/17/2013] [Indexed: 12/26/2022] Open
Abstract
Estrogen signaling is important for vertebrate embryonic development. Here we have used zebrafish (Danio rerio) as a vertebrate model to analyze estrogen signaling during development. Zebrafish embryos were exposed to 1 µM 17β-estradiol (E2) or vehicle from 3 hours to 4 days post fertilization (dpf), harvested at 1, 2, 3 and 4 dpf, and subjected to RNA extraction for transcriptome analysis using microarrays. Differentially expressed genes by E2-treatment were analyzed with hierarchical clustering followed by biological process and tissue enrichment analysis. Markedly distinct sets of genes were up and down-regulated by E2 at the four different time points. Among these genes, only the well-known estrogenic marker vtg1 was co-regulated at all time points. Despite this, the biological functional categories targeted by E2 were relatively similar throughout zebrafish development. According to knowledge-based tissue enrichment, estrogen responsive genes were clustered mainly in the liver, pancreas and brain. This was in line with the developmental dynamics of estrogen-target tissues that were visualized using transgenic zebrafish containing estrogen responsive elements driving the expression of GFP (Tg(5xERE:GFP)). Finally, the identified embryonic estrogen-responsive genes were compared to already published estrogen-responsive genes identified in male adult zebrafish (Gene Expression Omnibus database). The expressions of a few genes were co-regulated by E2 in both embryonic and adult zebrafish. These could potentially be used as estrogenic biomarkers for exposure to estrogens or estrogenic endocrine disruptors in zebrafish. In conclusion, our data suggests that estrogen effects on early embryonic zebrafish development are stage- and tissue- specific.
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Affiliation(s)
- Ruixin Hao
- Center for Nuclear Receptors and Cell Signaling, Department of Biology and Biochemistry, University of Houston, Houston, Texas, United States of America
| | - Maria Bondesson
- Center for Nuclear Receptors and Cell Signaling, Department of Biology and Biochemistry, University of Houston, Houston, Texas, United States of America
- * E-mail:
| | - Amar V. Singh
- National Center for Computational Toxicology, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina, United States of America
| | - Anne Riu
- Center for Nuclear Receptors and Cell Signaling, Department of Biology and Biochemistry, University of Houston, Houston, Texas, United States of America
| | - Catherine W. McCollum
- Center for Nuclear Receptors and Cell Signaling, Department of Biology and Biochemistry, University of Houston, Houston, Texas, United States of America
| | - Thomas B. Knudsen
- National Center for Computational Toxicology, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina, United States of America
| | - Daniel A. Gorelick
- Department of Embryology, Carnegie Institute for Science, Baltimore, Maryland, United States of America
| | - Jan-Åke Gustafsson
- Center for Nuclear Receptors and Cell Signaling, Department of Biology and Biochemistry, University of Houston, Houston, Texas, United States of America
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden
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8
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Potential tumorigenic programs associated with TP53 mutation status reveal role of VEGF pathway. Br J Cancer 2012; 107:1722-8. [PMID: 23079576 PMCID: PMC3493873 DOI: 10.1038/bjc.2012.461] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Background: Targeting differentially activated or perturbed tumour pathways is the key idea in individualised cancer therapy, which is emerging as an important option in treating cancers with poor prognostic profiles. TP53 mutation status is known as a core determinant of survival in breast cancer. The pathways disrupted in association with TP53 mutation status in tumours are not well characterised. Method: In this study, we stratify breast cancers based on their TP53 mutation status and identify the set of dysregulated tumorigenic pathways and corresponding candidate driver genes using breast cancer gene expression profiles. Expressions of these genes were evaluated for their effect on patient survival first in univariate models, followed by multivariate models with TP53 status as a covariate. Results: The most strongly differentially enriched pathways between breast cancers stratified by TP53 mutation status include in addition to TP53 signalling, several known cancer pathways involved in renal, prostate, pancreatic, colorectal, lung and other cancers, and signalling pathways such as calcium signalling, MAPK, ERBB and vascular endothelial growth factor (VEGF) signalling pathways. We found that mutant TP53 in conjunction with active estrogen receptor (ER) signalling significantly influence survival. We also found that upregulation of VEGFA mRNA levels in association with active ER signalling is a significant marker for poor survival, even in the presence of wild-type TP53. Conclusion: Mutation status of TP53 in breast cancer involves wide ranging derangement of several pathways. Among the candidate genes of the significantly deranged pathways, we identified VEGFA expression as an important marker of survival even when controlled by TP53 mutation status. Interestingly, independent of the TP53 mutation status, the survival effect of VEGFA was found significant in patients with active ER signalling (ER/PgR+), but not in those with ER/PgR− status. Therefore, we propose more studies to focus on the role of complex interplay between TP53, ER and VEGF signalling from therapeutic and prognostic context in breast cancer.
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Latasa MJ, Cosgaya JM. Regulation of retinoid receptors by retinoic acid and axonal contact in Schwann cells. PLoS One 2011; 6:e17023. [PMID: 21386894 PMCID: PMC3046125 DOI: 10.1371/journal.pone.0017023] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Accepted: 01/18/2011] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND Schwann cells (SCs) are the cell type responsible for the formation of the myelin sheath in the peripheral nervous system (PNS). As retinoic acid (RA) and other retinoids have a profound effect as regulators of the myelination program, we sought to investigate how their nuclear receptors levels were regulated in this cell type. METHODOLOGY/PRINCIPAL FINDINGS In the present study, by using Schwann cells primary cultures from neonatal Wistar rat pups, as well as myelinating cocultures of Schwann cells with embryonic rat dorsal root ganglion sensory neurons, we have found that sustained expression of RXR-γ depends on the continuous presence of a labile activator, while axonal contact mimickers produced an increase in RXR-γ mRNA and protein levels, increment that could be prevented by RA. The upregulation by axonal contact mimickers and the transcriptional downregulation by RA were dependent on de novo protein synthesis and did not involve changes in mRNA stability. On the other hand, RAR-β mRNA levels were only slightly modulated by axonal contact mimickers, while RA produced a strong transcriptional upregulation that was independent of de novo protein synthesis without changes in mRNA stability. CONCLUSIONS/SIGNIFICANCE All together, our results show that retinoid receptors are regulated in a complex manner in Schwann cells, suggesting that they could have a prominent role as regulators of Schwann cell physiology.
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Affiliation(s)
- Maria-Jesus Latasa
- Department of Endocrine and Nervous System Physiopathology, Instituto de Investigaciones Biomédicas, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, Madrid, Spain
| | - Jose Miguel Cosgaya
- Department of Endocrine and Nervous System Physiopathology, Instituto de Investigaciones Biomédicas, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, Madrid, Spain
- * E-mail:
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10
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Chalabi N, Delort L, Satih S, Déchelotte P, Bignon YJ, Bernard-Gallon DJ. Immunohistochemical expression of RARalpha, RARbeta, and Cx43 in breast tumor cell lines after treatment with lycopene and correlation with RT-QPCR. J Histochem Cytochem 2007; 55:877-83. [PMID: 17438348 DOI: 10.1369/jhc.7a7185.2007] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Lycopene, the major carotenoid found in tomatoes, is a potent antioxidant associated with the prevention of degenerative diseases such as breast cancer. This effect could be due to the interaction between lycopene and retinoic acid receptors as well as the stimulation of gap junction communication and synthesis of connexin 43. The expression of the RARalpha, RARbeta, and Cx43 proteins was analyzed using immunohistochemistry in two breast cancer cell lines, MCF-7 and MDA-MB-231, and in a fibrocystic dystrophy cell line, MCF-10a, after a 48-hr exposure to 10 microM lycopene. A real-time quantitative PCR analysis was then performed to measure mRNA expression. RARalpha and Cx43 expression were increased at both mRNA and protein levels in two breast cell lines.
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Affiliation(s)
- Nasséra Chalabi
- Département d'Oncogénétique, Centre Jean Perrin, Clermont-Ferrand Cedex 1, France
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Zhelyaznik N, Mey J. Regulation of retinoic acid receptors alpha, beta and retinoid X receptor alpha after sciatic nerve injury. Neuroscience 2006; 141:1761-74. [PMID: 16782282 DOI: 10.1016/j.neuroscience.2006.05.021] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2005] [Revised: 05/09/2006] [Accepted: 05/10/2006] [Indexed: 11/15/2022]
Abstract
Cell culture experiments indicated that activation of the retinoic acid signaling system is involved in axonal regeneration. This hypothesis was tested with sciatic nerve injury in the rat. Since the effect of retinoic acid is mediated via retinoic acid receptors and retinoid X receptors, we investigated mRNA and protein expression of these receptors during injury-induced degeneration and regeneration. Seven days after crush injury, transcript concentrations of all retinoic acid receptors and of retinoid X receptor alpha were significantly higher than in non-lesioned nerves. Protein levels of retinoic acid receptor alpha, retinoic acid receptor beta and retinoid X receptor alpha were upregulated 4, 7 and 14 days after injury. In degenerating nerves a significant increase of retinoic acid receptor alpha was detected 7 and 14 days, and of retinoic acid receptor beta 14 and 21 days after complete transection. Immunohistochemical staining of retinoid receptors revealed their expression in Schwann cells and macrophages. In addition, we observed that retinoic acid receptor alpha and retinoid X receptor alpha appeared in the cell nuclei of macrophages during the lesion-induced inflammatory reaction, and that retinoid X receptor alpha-staining co-localized with some regenerating axons. Experiments with Schwann cell primary cultures revealed an effect of retinoic acid on the expression of the neuregulin receptor ErbB3, suggesting that one function of retinoic acid consists in the regulation of neuroglial interactions after peripheral nerve injury.
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MESH Headings
- Animals
- Animals, Newborn
- Blotting, Northern/methods
- Blotting, Western/methods
- Cells, Cultured
- Disease Models, Animal
- Dose-Response Relationship, Drug
- Gene Expression Regulation/drug effects
- Gene Expression Regulation/physiology
- Immunohistochemistry/methods
- Macrophages/drug effects
- Macrophages/metabolism
- Male
- RNA, Messenger/biosynthesis
- Rats
- Rats, Sprague-Dawley
- Receptor, Nerve Growth Factor/genetics
- Receptor, Nerve Growth Factor/metabolism
- Receptors, Retinoic Acid/classification
- Receptors, Retinoic Acid/genetics
- Receptors, Retinoic Acid/metabolism
- Reverse Transcriptase Polymerase Chain Reaction/methods
- Schwann Cells/drug effects
- Schwann Cells/metabolism
- Sciatic Neuropathy/metabolism
- Sciatic Neuropathy/physiopathology
- Time Factors
- Tretinoin/pharmacology
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Affiliation(s)
- N Zhelyaznik
- Institut für Biologie II, RWTH Aachen, Kopernikusstrasse 16, 52074 Aachen, Germany
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12
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Lu M, Mira-y-Lopez R, Nakajo S, Nakaya K, Jing Y. Expression of estrogen receptor alpha, retinoic acid receptor alpha and cellular retinoic acid binding protein II genes is coordinately regulated in human breast cancer cells. Oncogene 2005; 24:4362-9. [PMID: 15870697 DOI: 10.1038/sj.onc.1208661] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Human breast cancer cell lines expressing the estrogen receptor alpha (ERalpha), all-trans-retinoic acid (ATRA) receptor alpha (RARalpha) and cellular retinoic acid binding protein II (CRABPII) genes are sensitive to ATRA-mediated growth inhibition. To study the relationship among ERalpha, RARalpha and CRABPII expression, the protein levels of each member were compared in five breast cancer cell lines (T47D, MCF-7, ZR-75-1, Hs587 T and MDA-MB-231 cells) and two immortalized nontumorigenic breast epithelial cell lines (MTSV1.7 and MCF-10A). ERalpha, RARalpha and CRABPII proteins were detected in T47D, MCF-7 and ZR-75-1 cells but not in other tested cell lines. RARalpha and CRABPII proteins were either reduced or undetectable in T47D/C4:2W and MCF-7/ADR cells with lost expression of ERalpha. Estradiol increased and anti-estrogens (tamoxifen and ICI 164,384) downregulated the expression of both RARalpha and CRABPII proteins in T47D and MCF-7 cells. RARalpha antagonist Ro-41-5253 inhibited CRABPII expression, but not RARalpha expression in estradiol-treated T47D and MCF-7 cells. Suppression of ERalpha by small interfering RNA (siRNA) reduced RARalpha and CRABPII gene expression and siRNA suppression of RARalpha reduced CRABPII expression while having no effect on ERalpha in T47D cells. Transient transfection of either RARalpha or ERalpha expression vectors increased CRABPII expression in MDA-MB-231 cells but only RARalpha, not ERalpha, activated hCRABPII promoter reporter. These results indicate that there is a gene activation pathway in which ERalpha drives RARalpha transcription and RARalpha drives CRABPII transcription in ERalpha-positive human breast cancer cells.
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Affiliation(s)
- Min Lu
- Division of Hematology/Oncology, Department of Medicine, Mount Sinai School of Medicine, One Gustave L Levy Place, New York, NY 10029-6574, USA
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13
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Appleyard VCL, O'Neill MA, Murray KE, Bray SE, Thomson G, Kernohan NM, Varani J, Zhang J, Thompson AM. Activity of MDI-301, a novel synthetic retinoid, in xenografts. Anticancer Drugs 2005; 15:991-6. [PMID: 15514569 DOI: 10.1097/00001813-200411000-00009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The efficacy of MDI-301, a non-toxic novel synthetic retinoid, was found to be equivalent to the natural 9-cis-retinoic acid (RA) in vitro against estrogen-dependent MCF7 and T47D breast cancer cell lines which express RA receptor (RAR) alpha. Both retinoids also showed similar efficacy against established PC-3 prostate carcinoma xenografts. MCF7 tumor xenografts showed a reduction in tumor growth of 48% without systemic side-effects upon treatment with MDI-301 compared with MCF7 controls. Tumor xenografts derived from MDA-MB-231, an estrogen-independent breast cancer cell line that expresses low levels of RARalpha, were unresponsive. This study demonstrates that MDI-301 is as efficacious as 9-cis-RA against cancer cells with RARalpha, with no signs of toxicity in vivo, making it a potential candidate for cancer therapy.
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Affiliation(s)
- Virginia C L Appleyard
- Department of Surgery, Ninewells Hospital and Medical School, University of Dundee, Dundee, UK
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14
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Afonja O, Juste D, Das S, Matsuhashi S, Samuels HH. Induction of PDCD4 tumor suppressor gene expression by RAR agonists, antiestrogen and HER-2/neu antagonist in breast cancer cells. Evidence for a role in apoptosis. Oncogene 2004; 23:8135-45. [PMID: 15361828 DOI: 10.1038/sj.onc.1207983] [Citation(s) in RCA: 124] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The growth of human breast tumor cells is regulated through signaling involving cell surface growth factor receptors and nuclear receptors of the steroid/thyroid/retinoid receptor gene family. Retinoic acid receptors (RARs), members of the steroid/thyroid hormone receptor gene family, are ligand-dependent transcription factors, which have in vitro and in vivo growth inhibitory activity against breast cancer cells. RAR-agonists inhibit the proliferation of many human breast cancer cell lines, particularly those whose growth is stimulated by estradiol (E2) or growth factors. Additionally, RAR-agonists and synthetic retinoids such as Ferentinide have been shown to induce apoptosis in malignant breast cells but not normal breast cells. To better define the genes involved in RAR-mediated growth inhibition of breast cancer cells, we used oligonucleotide microarray analysis to create a database of genes that are potentially regulated by RAR-agonists in breast cancer cells. We found that PDCD4 (programmed cell death 4), a tumor suppressor gene presently being evaluated as a target for chemoprevention, was induced about three-fold by the RARalpha-selective agonist Am580, in T-47D breast cancer cells. RAR pan-agonists and Am580, but not retinoid X receptors (RXR)-agonists, stimulate the expression of PDCD4 in a wide variety of retinoid-inhibited breast cancer cell lines. RAR-agonists did not induce PDCD4 expression in breast cancer cell lines, which were not growth inhibited by retinoids. We also observed that antiestrogen and the HER-2/neu antagonist, Herceptin (Trastuzumab), also induced PDCD4 expression in T-47D cells, suggesting that PDCD4 may play a central role in growth inhibition in breast cancer cells. Transient overexpression of PDCD4 in T-47D (ER+, RAR+) and MDA-MB-231 (ER-, RAR-) cells resulted in apoptotic death, suggesting a role for PDCD4 in mediating apoptosis in breast cancer cells. PDCD4 protein expression has previously been reported in small ductal epithelium of normal breast. To date, there has been no report of induction of PDCD4 expression by RAR-agonists, antiestrogen or HER2/neu antagonist in breast cancer cells and its potential role in apoptosis in these cells.
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Affiliation(s)
- Olubunmi Afonja
- Department of Pediatrics, New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA
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15
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Abstract
Studies utilizing experimental animals, epidemiological approaches, cellular models, and clinical trials all provide evidence that retinoic acid and some of its synthetic derivatives (retinoids) are useful pharmacological agents in cancer therapy and prevention. In this chapter, we first review the current knowledge of retinoic acid receptors (RARs) and their role in mediating the actions of retinoic acid. We then focus on a discussion of RARalpha and acute promyelocytic leukemia followed by a discussion of the role of RARs, in particular RARbeta expression, in other cancer types. Loss of normal RAR function in the presence of physiological levels of RA (either due to alterations in the protein structure or level of expression) is associated with a variety of different cancers. In some cases treatment with pharmacological doses of RA can be effective.
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Affiliation(s)
- Dianne Robert Soprano
- Department of Biochemistry, Temple University School of Medicine, Philadelphia, Pennsylvania 19140, USA.
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16
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Stoll BA. Linkage between retinoid and fatty acid receptors: implications for breast cancer prevention. Eur J Cancer Prev 2002; 11:319-25. [PMID: 12195157 DOI: 10.1097/00008469-200208000-00002] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Certain dietary retinoids and polyunsaturated fatty acids (PUFAs) consistently inhibit progression of mammary carcinogenesis both in animal studies and cell culture, but clinically, their effect is inconsistent. New evidence of synergistic interaction between the nuclear receptors for the two groups of nutritional agents suggests that appropriate selective ligands from each group might be combined in breast cancer chemoprevention studies. Peroxisome proliferator-activated receptor (PPAR) gamma is a nuclear receptor that is activated by PUFAs, eicosanoids and antidiabetic agents such as troglitazone. Such activation can cause growth inhibition in human mammary cancer cells in culture and the effect is enhanced by ligands of retinoic acid receptor (RAR) and retinoid X receptor (RXR). In mouse mammary tissue in organ culture, an RXR-selective ligand has been shown to enhance the effect of troglitazone in suppressing carcinogen-induced pre-neoplastic changes. A PPAR/RXR heterodimer is involved in tumour growth inhibition and has been shown to bind directly to nuclear oestrogen response elements (ERE) independently of oestrogen receptor (ER) activity. A combination of an RXR-selective retinoid with either troglitazone or else a long-chain n-3 PUFA, is proposed for a short-term study in postmenopausal women after primary surgery for intraductal breast cancer. The resulting activation of PPAR/RXR expression may increase response to retinoid administration, especially in the presence of obesity and insulin resistance, because of the ability of PPAR gamma ligands to reduce insulin-like growth factor I (IGF-I) concentrations. Serial core biopsies of breast tissue over a short term are proposed to identify changes in phenotype, which may influence progression to invasiveness. In addition to cytomorphological criteria, expression of ER alpha and beta, RAR alpha and beta, and IGF-I receptor in the nucleus should be examined.
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Affiliation(s)
- B A Stoll
- Oncology Department, St Thomas' Hospital, London SE1 7EH, UK
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17
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Nesaretnam K, Jin Lim E, Reimann K, Lai LC. Effect of a carotene concentrate on the growth of human breast cancer cells and pS2 gene expression. Toxicology 2000; 151:117-26. [PMID: 11074306 DOI: 10.1016/s0300-483x(00)00235-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Breast cancer is the most common cancer in women worldwide. The growth of breast cancer cells is either hormone-dependent or hormone-independent. Both types are represented in vitro by the estrogen-receptor positive (ER+) MCF-7 and the estrogen-receptor negative (ER-) MDA-MB-231 cell lines, respectively. The pS2 gene is an estrogen-regulated gene and serves as a marker for the ER+ tumours. Carotenoids are pigments with anti-cancer properties besides having pro-vitamin A, antioxidant and free-radical quenching effects. This study was designed firstly, to compare the effect of palm oil carotene concentrate with retinoic acid on the growth of the ER+ MCF-7 and the ER- MDA-MB-231 cells; and secondly to evaluate the effect of the palm oil carotene concentrate on the regulation of pS2 mRNA. The growth experiments were performed with monolayer cells seeded in phenol red free RPMI 1640 culture media and subsequently treated with varying concentrations of either retinoic acid or palm oil carotenoids. The cell numbers were determined at the start of each experiment and then at successive time intervals. The results showed that the palm oil carotene concentrate caused dose-dependent inhibition of estradiol-stimulated growth of MCF-7 cells but did not affect the proliferation of MDA-MB-231 cells. Retinoic acid caused similar, albeit more potent effects, as significant inhibition was observed at lower concentrations than the palm oil carotenoids. In the pS2 gene expression experiment, cell monolayers were treated with the carotene concentrate (10(-6) M), either with or without supplemented estradiol (10(-8) M), and subsequently the RNA was extracted. Northern blotting was performed and the regulation of pS2 mRNA determined using a 32P-labelled pS2 cDNA probe. The results showed that the palm oil carotene concentrate did not affect the expression of pS2 mRNA and are therefore independent of the estrogen-regulated pathway.
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Affiliation(s)
- K Nesaretnam
- Palm Oil Research Institute of Malaysia, 6 Persiaran Institusi, Bandar Baru Bangi, 43000, Kajang, Malaysia.
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18
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Murakami K, Matsuura T, Hasumura S, Nagamori S, Yamada Y, Saiki I. Involvement of insulin-like growth factor binding protein-3 in the retinoic acid receptor-alpha-mediated inhibition of hepatocellular carcinoma cell proliferation. Cancer Lett 2000; 151:63-70. [PMID: 10766424 DOI: 10.1016/s0304-3835(99)00410-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
We examined the relationship between the expression of retinoic acid receptor-alpha (RAR-alpha) and upregulation of insulin-like growth factor binding protein-3 (IGFBP-3) in the retinoid-induced inhibition of hepatocellular carcinoma (HCC) cell proliferation. HCC cell lines showed a marked expression of RAR-alpha, whereas the expression levels of RAR-beta and RAR-gamma were relatively lower. An RAR-alpha agonist significantly inhibited the HCC cell proliferation both in vitro and in vivo. The RAR-alpha expression closely related to the upregulation of IGFBP-3 as compared with RAR-beta or RAR-alpha expressions. RAR-alpha agonist would be beneficial to inhibit the growth of HCC.
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Affiliation(s)
- K Murakami
- Department of Pathogenic Biochemistry, Institute of Natural Medicine, Toyama Medical and Pharmaceutical University, Japan.
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19
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Spinella MJ, Dmitrovsky E. Aberrant retinoid signaling and breast cancer: the view from outside the nucleus. J Natl Cancer Inst 2000; 92:438-40. [PMID: 10716952 DOI: 10.1093/jnci/92.6.438] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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20
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Abstract
Retinoids mediate a number of physiological pathways through their effects on cellular growth and differentiation. Upon binding to retinoic acid receptors (RARs) and retinoid X receptors (RXRs), retinoids regulate cellular processes by directly modulating the expression of responsive genes. The wide-ranging effects of retinoid action are attributable to two main factors-the ubiquitous distribution of several subtypes and isoforms of RARs and RXRs, and the ability of these receptors to regulate numerous genes upon ligand activation. The broad range of effects mediated by retinoids means not only that they have many potential therapeutic applications but also that non-selective retinoids are associated with a high incidence of adverse effects. The design of retinoids that are receptor-selective and function-selective is a strategy that is proving successful in developing novel retinoids that offer not only good efficacy but also good tolerability. Tazarotene, a receptor-selective retinoid indicated for the topical treatment of psoriasis, is at the forefront of this new generation of retinoids. In the near future, other receptor-selective retinoids may prove useful for the treatment of other dermatological diseases, cancer, and diabetes.
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Affiliation(s)
- A Johnson
- Retinoid Research, Department of Biology, Allergan Inc., Irvine, California 92623-9534, USA
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21
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Katsetos CD, Stadnicka I, Boyd JC, Ehya H, Zheng S, Soprano CM, Cooper HS, Patchefsky AS, Soprano DR, Soprano KJ. Cellular distribution of retinoic acid receptor-alpha protein in serous adenocarcinomas of ovarian, tubal, and peritoneal origin: comparison with estrogen receptor status. THE AMERICAN JOURNAL OF PATHOLOGY 1998; 153:469-80. [PMID: 9708807 PMCID: PMC1852976 DOI: 10.1016/s0002-9440(10)65590-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 05/18/1998] [Indexed: 11/16/2022]
Abstract
Retinoids are effective growth modulators of human ovarian carcinoma cell lines. Their effects are mediated by nuclear retinoic acid receptors (RARs) and retinoid X receptors (RXRs), which are transcriptional factors and members of the steroid/thyroid receptor superfamily. To our knowledge, until now, the cellular distribution of RAR proteins in human ovarian tumor specimens is unknown. This study provides new data on the differential cellular localization of RAR alpha protein in 16 serous adenocarcinomas originating from the ovaries, fallopian tubes, and the peritoneum. Using an affinity-purified antiserum specific for RAR alpha and a monoclonal antibody recognizing the full-length estrogen receptor molecule (clone 6F11), we performed immunohistochemistry on frozen tissue sections and examined the relationship between RAR alpha and estrogen receptor protein expression by comparing the percentage of immunostained tumor cells for either receptor. Our findings indicate a strong linear relationship between the percentages of RAR alpha- and estrogen receptor-labeled tumor cells as determined by linear regression analysis (P < 0.005, r = 0.825). A modest inverse relationship was found between the percentage of RAR alpha-positive tumor cells and histological grade, attesting to a differentiation-dependent trend (P < 0.04). No significant relationship was found between RAR alpha-labeled cells and clinical stage (P = 0.139), site of tumor origin (ovaries versus fallopian tubes versus peritoneum) (P = 0.170), and primary versus metastatic lesion (P = 0.561). Thus, serous adenocarcinomas are capable of expressing RAR alpha and estrogen receptor despite high histological grade and advanced stage of neoplastic disease. Compared with the heterogeneous localization of RAR alpha in cancer cells, there was widespread RAR alpha immunoreactivity in tumor-infiltrating lymphocytes, vascular endothelial cells, and stromal fibroblasts, underscoring the value of immunohistochemistry in the accurate determination of RAR/(RXR) content in tumor specimens.
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MESH Headings
- Adenocarcinoma/metabolism
- Adenocarcinoma/pathology
- Adult
- Aged
- Aged, 80 and over
- Blotting, Western
- Fallopian Tube Neoplasms/metabolism
- Fallopian Tube Neoplasms/pathology
- Female
- Humans
- Immunoenzyme Techniques
- Middle Aged
- Neoplasms, Cystic, Mucinous, and Serous/metabolism
- Neoplasms, Cystic, Mucinous, and Serous/pathology
- Ovarian Neoplasms/metabolism
- Ovarian Neoplasms/pathology
- Peritoneal Neoplasms/metabolism
- Peritoneal Neoplasms/pathology
- Receptors, Estrogen/metabolism
- Receptors, Retinoic Acid/metabolism
- Retinoic Acid Receptor alpha
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Affiliation(s)
- C D Katsetos
- Department of Microbiology and Immunology, Temple University School of Medicine, Philadelphia, Pennsylvania, USA.
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22
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Boehm N, Chateau D, Rochette-Egly C. Retinoid receptors in rat vaginal and uterine epithelia: changes with ovarian steroids. Mol Cell Endocrinol 1997; 132:101-8. [PMID: 9324051 DOI: 10.1016/s0303-7207(97)00126-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
In rats, vaginal epithelium shows cyclic changes with an alternating pattern of keratinization under estrogen control and mucification under progesterone control. Since retinoids suppress keratinizing differentiation, in this paper we studied the expression of the major retinoid receptors normally present in keratinizing squamous epithelia: RAR alpha, RAR gamma and RXR alpha. In cyclic rats and steroid-treated ovariectomized rats, RXR alpha and RAR gamma were detected in basal and suprabasal cells while RAR alpha was mainly localized in suprabasal cells. No changes in RAR gamma expression were observed in correlation with ovarian steroids. During diestrus and in ovariectomized rats, the superficial cuboid cells expressed the three receptors. In the uterine epithelium, RAR alpha, RAR gamma and RXR alpha expression was induced by estrogens. Retinoic acid treatment did not modify retinoid receptor expression in vaginal and uterine epithelia. These data suggest specific roles for the different receptors in the complex process of vaginal epithelium proliferation and differentiation under estrogens and retinoic acid control.
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Affiliation(s)
- N Boehm
- Institut d'Histologie, Faculté de Médecine, Strasbourg, France
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