1
|
Bagherifard A, Hosseinzadeh A, Koosha F, Sheibani M, Karimi-Behnagh A, Reiter RJ, Mehrzadi S. Melatonin and bone-related diseases: an updated mechanistic overview of current evidence and future prospects. Osteoporos Int 2023; 34:1677-1701. [PMID: 37393580 DOI: 10.1007/s00198-023-06836-1] [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: 04/04/2023] [Accepted: 06/16/2023] [Indexed: 07/04/2023]
Abstract
PURPOSE Bone diseases account for an enormous cost burden on health systems. Bone disorders are considered as age-dependent diseases. The aging of world population has encouraged scientists to further explore the most effective preventive modalities and therapeutic strategies to overcome and reduce the high cost of bone disorders. Herein, we review the current evidence of melatonin's therapeutic effects on bone-related diseases. METHODS This review summarized evidences from in vitro, in vivo, and clinical studies regarding the effects of melatonin on bone-related diseases, with a focus on the molecular mechanisms. Electronically, Scopus and MEDLINE®/PubMed databases were searched for articles published on melatonin and bone-related diseases from inception to June 2023. RESULTS The findings demonstrated that melatonin has beneficial effect in bone- and cartilage-related disorders such as osteoporosis, bone fracture healing, osteoarthritis, and rheumatoid arthritis, in addition to the control of sleep and circadian rhythms. CONCLUSION A number of animal and clinical studies have indicated that various biological effects of melatonin may suggest this molecule as an effective therapeutic agent for controlling, diminishing, or suppressing bone-related disorders. Therefore, further clinical studies are required to clarify whether melatonin can be effective in patients with bone-related diseases.
Collapse
Affiliation(s)
- Abolfazl Bagherifard
- Bone and Joint Reconstruction Research Center, Department of Orthopedics, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Azam Hosseinzadeh
- Razi Drug Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Fereshteh Koosha
- Department of Radiology Technology, Faculty of Allied Medical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Sheibani
- Razi Drug Research Center, Iran University of Medical Sciences, Tehran, Iran
- Department of Pharmacology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | | | - Russel J Reiter
- Department of Cellular and Structural Biology, Long School of Medicine, UT Health San Antonio, San Antonio, TX, USA
| | - Saeed Mehrzadi
- Razi Drug Research Center, Iran University of Medical Sciences, Tehran, Iran.
| |
Collapse
|
2
|
Malik S, Stokes Iii J, Manne U, Singh R, Mishra MK. Understanding the significance of biological clock and its impact on cancer incidence. Cancer Lett 2022; 527:80-94. [PMID: 34906624 PMCID: PMC8816870 DOI: 10.1016/j.canlet.2021.12.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 12/01/2021] [Accepted: 12/02/2021] [Indexed: 12/12/2022]
Abstract
The circadian clock is an essential timekeeper that controls, for humans, the daily rhythm of biochemical, physiological, and behavioral functions. Irregular performance or disruption in circadian rhythms results in various diseases, including cancer. As a factor in cancer development, perturbations in circadian rhythms can affect circadian homeostasis in energy balance, lead to alterations in the cell cycle, and cause dysregulation of chromatin remodeling. However, knowledge gaps remain in our understanding of the relationship between the circadian clock and cancer. Therefore, a mechanistic understanding by which circadian disruption enhances cancer risk is needed. This review article outlines the importance of the circadian clock in tumorigenesis and summarizes underlying mechanisms in the clock and its carcinogenic mechanisms, highlighting advances in chronotherapy for cancer treatment.
Collapse
Affiliation(s)
- Shalie Malik
- Cancer Biology Research and Training, Department of Biological Sciences, Alabama State University, Montgomery, AL, USA; Department of Zoology and Dr. Giri Lal Gupta Institute of Public Health and Public Affairs, University of Lucknow, Lucknow, UP, India
| | - James Stokes Iii
- Department of Biological and Environmental Sciences, Auburn University, Montgomery, AL, USA
| | - Upender Manne
- Departments of Pathology, Surgery and Epidemiology, O'Neal Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Rajesh Singh
- Department of Microbiology, Biochemistry, and Immunology, Cancer Health Equity Institute, Morehouse School of Medicine, Atlanta, GA, USA
| | - Manoj K Mishra
- Cancer Biology Research and Training, Department of Biological Sciences, Alabama State University, Montgomery, AL, USA.
| |
Collapse
|
3
|
MacDonald IJ, Tsai HC, Chang AC, Huang CC, Yang SF, Tang CH. Melatonin Inhibits Osteoclastogenesis and Osteolytic Bone Metastasis: Implications for Osteoporosis. Int J Mol Sci 2021; 22:ijms22179435. [PMID: 34502344 PMCID: PMC8430520 DOI: 10.3390/ijms22179435] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 08/25/2021] [Accepted: 08/27/2021] [Indexed: 12/16/2022] Open
Abstract
Osteoblasts and osteoclasts are major cellular components in the bone microenvironment and they play a key role in the bone turnover cycle. Many risk factors interfere with this cycle and contribute to bone-wasting diseases that progressively destroy bone and markedly reduce quality of life. Melatonin (N-acetyl-5-methoxy-tryptamine) has demonstrated intriguing therapeutic potential in the bone microenvironment, with reported effects that include the regulation of bone metabolism, acceleration of osteoblastogenesis, inhibition of osteoclastogenesis and the induction of apoptosis in mature osteoclasts, as well as the suppression of osteolytic bone metastasis. This review aims to shed light on molecular and clinical evidence that points to possibilities of melatonin for the treatment of both osteoporosis and osteolytic bone metastasis. It appears that the therapeutic qualities of melatonin supplementation may enable existing antiresorptive osteoporotic drugs to treat osteolytic metastasis.
Collapse
Affiliation(s)
- Iona J. MacDonald
- Graduate Institute of Basic Medical Science, China Medical University, Taichung 40402, Taiwan; (I.J.M.); (H.-C.T.)
| | - Hsiao-Chi Tsai
- Graduate Institute of Basic Medical Science, China Medical University, Taichung 40402, Taiwan; (I.J.M.); (H.-C.T.)
| | - An-Chen Chang
- Translational Medicine Center, Shin Kong Wu Ho-Su Memorial Hospital, Taipei City 111, Taiwan;
| | - Chien-Chung Huang
- School of Medicine, China Medical University, Taichung 40402, Taiwan;
- Division of Immunology and Rheumatology, Department of Internal Medicine, China Medical University Hospital, Taichung 40447, Taiwan
| | - Shun-Fa Yang
- Institute of Medicine, Chung Shan Medical University, Taichung 40201, Taiwan;
- Department of Medical Research, Chung Shan Medical University Hospital, Taichung 40201, Taiwan
| | - Chih-Hsin Tang
- Graduate Institute of Basic Medical Science, China Medical University, Taichung 40402, Taiwan; (I.J.M.); (H.-C.T.)
- School of Medicine, China Medical University, Taichung 40402, Taiwan;
- Graduate Institute of Biomedical Sciences, China Medical University, Taichung 40402, Taiwan
- Chinese Medicine Research Center, China Medical University, Taichung 40402, Taiwan
- Department of Biotechnology, College of Health Science, Asia University, Taichung 41354, Taiwan
- Correspondence: ; Tel.: +886-2205-2121 (ext. 7726)
| |
Collapse
|
4
|
Lu KH, Lin RC, Yang JS, Yang WE, Reiter RJ, Yang SF. Molecular and Cellular Mechanisms of Melatonin in Osteosarcoma. Cells 2019; 8:E1618. [PMID: 31842295 PMCID: PMC6952995 DOI: 10.3390/cells8121618] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 12/06/2019] [Accepted: 12/09/2019] [Indexed: 02/06/2023] Open
Abstract
Osteosarcoma, the most common primary bone malignancy, occurs most frequently in adolescents with a peak of incidence at 11-15 years. Melatonin, an indole amine hormone, shows a wide range of anticancer activities. The decrease in melatonin levels simultaneously concurs with the increase in bone growth and the peak age distribution of osteosarcoma during puberty, so melatonin has been utilized as an adjunct to chemotherapy to improve the quality of life and clinical outcomes. While a large amount of research has been conducted to understand the complex pleiotropic functions and the molecular and cellular actions elicited by melatonin in various types of cancers, a few review reports have focused on osteosarcoma. Herein, we summarized the anti-osteosarcoma effects of melatonin and its underlying molecular mechanisms to illustrate the known significance of melatonin in osteosarcoma and to address cellular signaling pathways of melatonin in vitro and in animal models. Even in the same kind of osteosarcoma, melatonin has been sparingly investigated to counteract tumor growth, apoptosis, and metastasis through different mechanisms, depending on different cell lines. We highlighted the underlying mechanism of anti-osteosarcoma properties evoked by melatonin, including antioxidant activity, anti-proliferation, induction of apoptosis, and the inhibition of invasion and metastasis. Moreover, we discussed the drug synergy effects of the role of melatonin involved and the method to fortify the anti-cancer effects on osteosarcoma. As a potential therapeutic agent, melatonin is safe for children and adolescents and is a promising candidate for an adjuvant by reinforcing the therapeutic effects and abolishing the unwanted consequences of chemotherapies.
Collapse
Affiliation(s)
- Ko-Hsiu Lu
- Department of Orthopedics, Chung Shan Medical University Hospital, Taichung 402, Taiwan; (K.-H.L.); (R.-C.L.)
- School of Medicine, Chung Shan Medical University, Taichung 402, Taiwan
| | - Renn-Chia Lin
- Department of Orthopedics, Chung Shan Medical University Hospital, Taichung 402, Taiwan; (K.-H.L.); (R.-C.L.)
- School of Medicine, Chung Shan Medical University, Taichung 402, Taiwan
- Division of Hyperbaric Oxygen Therapy and Wound Medicine, Chung Shan Medical University Hospital, Taichung 402, Taiwan
| | - Jia-Sin Yang
- Institute of Medicine, Chung Shan Medical University, Taichung 402, Taiwan; (J.-S.Y.); (W.-E.Y.)
- Department of Medical Research, Chung Shan Medical University Hospital, Taichung 402, Taiwan
| | - Wei-En Yang
- Institute of Medicine, Chung Shan Medical University, Taichung 402, Taiwan; (J.-S.Y.); (W.-E.Y.)
- Department of Medical Research, Chung Shan Medical University Hospital, Taichung 402, Taiwan
| | - Russel J. Reiter
- Department of Cell Systems and Anatomy, UT Health, San Antonio, TX 78229, USA
| | - Shun-Fa Yang
- Institute of Medicine, Chung Shan Medical University, Taichung 402, Taiwan; (J.-S.Y.); (W.-E.Y.)
- Department of Medical Research, Chung Shan Medical University Hospital, Taichung 402, Taiwan
| |
Collapse
|
5
|
Çetin Altındal D, Gümüşderelioğlu M. Dual-functional melatonin releasing device loaded with PLGA microparticles and cyclodextrin inclusion complex for osteosarcoma therapy. J Drug Deliv Sci Technol 2019. [DOI: 10.1016/j.jddst.2019.05.027] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
6
|
Nirvani M, Khuu C, Utheim TP, Sand LP, Sehic A. Circadian clock and oral cancer. Mol Clin Oncol 2017; 8:219-226. [PMID: 29435282 PMCID: PMC5774470 DOI: 10.3892/mco.2017.1518] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 10/24/2017] [Indexed: 12/20/2022] Open
Abstract
The circadian clock is comprised of a master component situated in the hypothalamic suprachiasmatic nucleus and subordinate clock genes in almost every cell of the body. The circadian clock genes and their encoded proteins govern the organism to follow the natural signals of time, and adapt to external changes in the environment. The majority of physiological processes in mammals exhibit variable circadian rhythms, which are generated and coordinated by an oscillation in the expression of the clock genes. A number of studies have reported that alteration in the expression level of clock genes is correlated with several pathological conditions, including cancer. However, little is known about the role of clock genes in homeostasis of the oral epithelium and their disturbances in oral carcinogenesis. The present review summarizes the current state of knowledge of the implications of clock genes in oral cancer. It has been demonstrated that the development of oral squamous cell carcinoma undergoes circadian oscillation in relation to tumor volume and proliferation rate. The circadian clock gene period (PER)1 has been associated with oral cancer pathogenesis and it is suggested that changes in the expression of PER1 may exhibit an important role in the development, invasion, and metastasis of oral squamous cell carcinoma. However, its role remains elusive and there is a need for further research in order to understand the underlying mechanisms of the clock genes in oral cancer pathogenesis.
Collapse
Affiliation(s)
- Minou Nirvani
- Department of Oral Biology, Faculty of Dentistry, University of Oslo, 0316 Oslo, Norway
| | - Cuong Khuu
- Department of Oral Biology, Faculty of Dentistry, University of Oslo, 0316 Oslo, Norway
| | - Tor Paaske Utheim
- Department of Oral Biology, Faculty of Dentistry, University of Oslo, 0316 Oslo, Norway.,Department of Medical Biochemistry, Oslo University Hospital, 0424 Oslo, Norway
| | - Lars Peter Sand
- Department of Oral Biology, Faculty of Dentistry, University of Oslo, 0316 Oslo, Norway
| | - Amer Sehic
- Department of Oral Biology, Faculty of Dentistry, University of Oslo, 0316 Oslo, Norway
| |
Collapse
|
7
|
Maritim AC, Moore BH, Sanders RA, Watkins JB. Effects of Melatonin on Oxidative Stress in Streptozotocin-Induced Diabetic Rats. Int J Toxicol 2016. [DOI: 10.1080/109158199225440] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Oxidative stress plays an important role in diabetes and other oxygen-related diseases. Melatonin, a pineal hormone thought to be a scavenger of oxygen radicals and a potentially advantageous therapeutic agent in diseases having oxidative stress, was administered (10 mg/kg ip, in gum tragacanth to prolong its absorption, once a day for 4 successive days) to normal and 30-day streptozotocin-induced diabetic Sprague-Dawley rats, after which markers of oxidative stress were assessed in the liver, kidney, intestine, and spleen. Alanine and aspartate aminotransferase activities in serum, which were increased after diabetes, were not increased further by melatonin administration, indicating that there was no melatonin-related liver toxicity. Most melatonin-induced effects were seen in the liver, and very few in extrahepatic tissues. In livers of diabetic rats, reduced concentration of nitrite and increased lipid peroxidation were both restored to normal levels following treatment with melatonin. Hepatic glutathione peroxidase activity was not changed in diabetics, but was decreased after melatonin administration in both normal and diabetic animals. Total glutathione concentrations were significantly decreased in livers of all diabetics and were not normalized by melatonin treatment. Hepatic superoxide dis-mutase activity was elevated following melatonin dosing in normal rats, but dropped below normal levels in diabetic rats and was not restored by melatonin treatment. Glutathione 5-transferase activity was higher than normal in melatonin-dosed normal rat livers. These results suggest that after 4 days of administration, melatonin may enable various enzymes of the hepatic antioxidative defense system to better detoxify harmful oxygen radicals without producing overt toxicity in a disease such as diabetes.
Collapse
Affiliation(s)
| | - Brian H. Moore
- Medical Sciences Program, Indiana University School of Medicine, Bloomington, Indiana, USA
| | - Ruth A. Sanders
- Medical Sciences Program, Indiana University School of Medicine, Bloomington, Indiana, USA
| | - John B. Watkins
- Medical Sciences Program, Indiana University School of Medicine, Bloomington, Indiana, USA
| |
Collapse
|
8
|
Abstract
Humans as diurnal beings are active during the day and rest at night. This daily oscillation of behavior and physiology is driven by an endogenous circadian clock not environmental cues. In modern societies, changes in lifestyle have led to a frequent disruption of the endogenous circadian homeostasis leading to increased risk of various diseases including cancer. The clock is operated by the feedback loops of circadian genes and controls daily physiology by coupling cell proliferation and metabolism, DNA damage repair, and apoptosis in peripheral tissues with physical activity, energy homeostasis, immune and neuroendocrine functions at the organismal level. Recent studies have revealed that defects in circadian genes due to targeted gene ablation in animal models or single nucleotide polymorphism, deletion, deregulation and/or epigenetic silencing in humans are closely associated with increased risk of cancer. In addition, disruption of circadian rhythm can disrupt the molecular clock in peripheral tissues in the absence of circadian gene mutations. Circadian disruption has recently been recognized as an independent cancer risk factor. Further study of the mechanism of clock-controlled tumor suppression will have a significant impact on human health by improving the efficiencies of cancer prevention and treatment.
Collapse
Affiliation(s)
- Nicole M Kettner
- Department of Pediatrics/U.S. Department of Agriculture/Agricultural Research Service/ Children's Nutrition Research Center, Baylor College of Medicine , Houston, TX , USA
| | | | | |
Collapse
|
9
|
Fu L, Kettner NM. The circadian clock in cancer development and therapy. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2013; 119:221-82. [PMID: 23899600 PMCID: PMC4103166 DOI: 10.1016/b978-0-12-396971-2.00009-9] [Citation(s) in RCA: 172] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Most aspects of mammalian function display circadian rhythms driven by an endogenous clock. The circadian clock is operated by genes and comprises a central clock in the brain that responds to environmental cues and controls subordinate clocks in peripheral tissues via circadian output pathways. The central and peripheral clocks coordinately generate rhythmic gene expression in a tissue-specific manner in vivo to couple diverse physiological and behavioral processes to periodic changes in the environment. However, with the industrialization of the world, activities that disrupt endogenous homeostasis with external circadian cues have increased. This change in lifestyle has been linked to an increased risk of diseases in all aspects of human health, including cancer. Studies in humans and animal models have revealed that cancer development in vivo is closely associated with the loss of circadian homeostasis in energy balance, immune function, and aging, which are supported by cellular functions important for tumor suppression including cell proliferation, senescence, metabolism, and DNA damage response. The clock controls these cellular functions both locally in cells of peripheral tissues and at the organismal level via extracellular signaling. Thus, the hierarchical mammalian circadian clock provides a unique system to study carcinogenesis as a deregulated physiological process in vivo. The asynchrony between host and malignant tissues in cell proliferation and metabolism also provides new and exciting options for novel anticancer therapies.
Collapse
Affiliation(s)
- Loning Fu
- Department of Pediatrics/U.S. Department of Agriculture/Agricultural Research Service/Children's Nutrition Research Center, Baylor College of Medicine, Houston, TX, USA
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
- Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX, USA
| | - Nicole M. Kettner
- Department of Pediatrics/U.S. Department of Agriculture/Agricultural Research Service/Children's Nutrition Research Center, Baylor College of Medicine, Houston, TX, USA
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
| |
Collapse
|
10
|
Lee S, Donehower LA, Herron AJ, Moore DD, Fu L. Disrupting circadian homeostasis of sympathetic signaling promotes tumor development in mice. PLoS One 2010; 5:e10995. [PMID: 20539819 PMCID: PMC2881876 DOI: 10.1371/journal.pone.0010995] [Citation(s) in RCA: 193] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2009] [Accepted: 05/11/2010] [Indexed: 01/17/2023] Open
Abstract
Background Cell proliferation in all rapidly renewing mammalian tissues follows a circadian rhythm that is often disrupted in advanced-stage tumors. Epidemiologic studies have revealed a clear link between disruption of circadian rhythms and cancer development in humans. Mice lacking the circadian genes Period1 and 2 (Per) or Cryptochrome1 and 2 (Cry) are deficient in cell cycle regulation and Per2 mutant mice are cancer-prone. However, it remains unclear how circadian rhythm in cell proliferation is generated in vivo and why disruption of circadian rhythm may lead to tumorigenesis. Methodology/Principal Findings Mice lacking Per1 and 2, Cry1 and 2, or one copy of Bmal1, all show increased spontaneous and radiation-induced tumor development. The neoplastic growth of Per-mutant somatic cells is not controlled cell-autonomously but is dependent upon extracellular mitogenic signals. Among the circadian output pathways, the rhythmic sympathetic signaling plays a key role in the central-peripheral timing mechanism that simultaneously activates the cell cycle clock via AP1-controlled Myc induction and p53 via peripheral clock-controlled ATM activation. Jet-lag promptly desynchronizes the central clock-SNS-peripheral clock axis, abolishes the peripheral clock-dependent ATM activation, and activates myc oncogenic potential, leading to tumor development in the same organ systems in wild-type and circadian gene-mutant mice. Conclusions/Significance Tumor suppression in vivo is a clock-controlled physiological function. The central circadian clock paces extracellular mitogenic signals that drive peripheral clock-controlled expression of key cell cycle and tumor suppressor genes to generate a circadian rhythm in cell proliferation. Frequent disruption of circadian rhythm is an important tumor promoting factor.
Collapse
Affiliation(s)
- Susie Lee
- Department of Pediatrics/U.S. Department of Agriculture/Agricultural Research Service/Children's Nutrition Research Center, Baylor College of Medicine, Houston, Texas, United States of America
| | | | | | | | | |
Collapse
|
11
|
Toma CD, Svoboda M, Arrich F, Ekmekcioglu C, Assadian O, Thalhammer T. Expression of the melatonin receptor (MT) 1 in benign and malignant human bone tumors. J Pineal Res 2007; 43:206-13. [PMID: 17645699 DOI: 10.1111/j.1600-079x.2007.00464.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The beneficial effects of melatonin on bone homeostasis have been shown in various diseases. As this indoleamine causes dose-dependent modulation of bone-forming osteoblast and bone-resorbing osteoclast activities by receptor-independent and -dependent pathways, we investigated the expression of G-protein-coupled melatonin receptors (MTs) in malignant and non-malignant human bone lesions. By TaqMan polymerase chain reaction (PCR), we analyzed 30 specimens from osteosarcoma and 11 from benign bone tumors for MT1-mRNA expression. Furthermore, we determined mRNA expression levels of the osteoclast activity-stimulating receptor activator of nuclear factor-kappa B ligand (RANKL) and its counterpart osteoprotegerin (OPG). Although mean MT1-mRNA levels were similar (P = 0.596) in malignant (4.39 +/- 4.98-fold) and benign samples (4.64 +/- 6.81-fold), the highest MT1-mRNA levels (up to 27-fold) were observed in individual osteosarcomas, particularly, in two specimens of patients with local recurrence of the tumor. Moreover, mean RANKL- and OPG-mRNA levels were similar in malignant and benign specimens (RANKL: 7.38 +/- 9.61-fold versus 3.57 +/- 3.11-fold, P = 0.207; OPG: 23.45 +/- 32.76 versus 8.07 +/- 7.23-fold, P = 0.133). Again, highest RANKL- and OPG-mRNA levels (up to 41- and 160-fold, respectively) were observed in individual osteosarcomas. Expression of MT1-mRNA was confirmed in two human osteosarcoma cell lines (HOS, MG63). High expression levels of MT1-mRNA together with low OPG-mRNA were found in both osteosarcoma cell lines, while in normal human osteoblasts and bone marrow stromal cells, high OPG-mRNA levels were associated with low MT1-mRNA levels. These data on the abundant expression of MT1-mRNA in human bone tumors and osteosarcoma cells lines suggest an important role for MT1 in bone pathology.
Collapse
Affiliation(s)
- Cyril D Toma
- Department of Orthopaedic Surgery, Medical University of Vienna, Vienna, Austria
| | | | | | | | | | | |
Collapse
|