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Johnson RW, Rhoades J, Martin TJ. Parathyroid hormone-related protein in breast cancer bone metastasis. VITAMINS AND HORMONES 2022; 120:215-230. [PMID: 35953110 DOI: 10.1016/bs.vh.2022.04.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Parathyroid hormone-related protein (PTHrP) was discovered as the tumor product causing the humoral hypercalcemia of malignancy. Its structural similarity to the hormone, PTH, with 8 of the first 13 amino acids identical, was sufficient to explain the sharing by PTHrP and PTH of a common receptor, PTH1R, although the remainder of the sequences are unique. PTHrP has important roles in development of several organs, including breast and bone, and functions as a paracrine factor postnatally in these and other tissues. In addition to its hormonal role in cancer, PTHrP is produced by two thirds of primary breast cancers and 90% of bone metastases from breast cancer, leading to the concept that its production in bone by breast cancer cells promotes bone resorption, thus favoring tumor establishment and expansion, and an exit from tumor dormancy in bone through downregulation of leukemia inducing factor receptor (LIFR). Cancer production of PTHrP is increased by bone-derived growth factors, with particular attention paid to TGFβ, as well as by promoter-driven transcriptional effects, such as the hedgehog signaling factor, GLI2, and microenvironment effects including changes in underlying stiffness of substrates for cells. Although interest has been focused on PTHrP-induced bone resorption in bone metastasis, a mechanistically separate, protective effect against tumor progression has been proposed. Although there is conflicting mouse data, there are clinical studies suggesting that increased production of PTHrP by breast cancers confers upon them a less invasive phenotype, an effect distinct from the bone resorption-stimulating action that favors bone metastasis.
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Affiliation(s)
- Rachelle W Johnson
- Department of Medicine, Division of Clinical Pharmacology, and Vanderbilt Center for Bone Biology, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Julie Rhoades
- Department of Medicine, Division of Clinical Pharmacology, and Vanderbilt Center for Bone Biology, Vanderbilt University Medical Center, Nashville, TN, United States; Department of Veterans Affairs, Tennessee Valley Healthcare System, Nashville, TN, United States
| | - T John Martin
- St Vincent's Institute of Medical Research, University of Melbourne, St Vincent's Health, Melbourne, VIC, Australia.
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Edwards CM, Johnson RW. From Good to Bad: The Opposing Effects of PTHrP on Tumor Growth, Dormancy, and Metastasis Throughout Cancer Progression. Front Oncol 2021; 11:644303. [PMID: 33828987 PMCID: PMC8019909 DOI: 10.3389/fonc.2021.644303] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Accepted: 02/22/2021] [Indexed: 11/13/2022] Open
Abstract
Parathyroid hormone related protein (PTHrP) is a multifaceted protein with several biologically active domains that regulate its many roles in normal physiology and human disease. PTHrP causes humoral hypercalcemia of malignancy (HHM) through its endocrine actions and tumor-induced bone destruction through its paracrine actions. PTHrP has more recently been investigated as a regulator of tumor dormancy owing to its roles in regulating tumor cell proliferation, apoptosis, and survival through autocrine/paracrine and intracrine signaling. Tumor expression of PTHrP in late stages of cancer progression has been shown to promote distant metastasis formation, especially in bone by promoting tumor-induced osteolysis and exit from dormancy. In contrast, PTHrP may protect against further tumor progression and improve patient survival in early disease stages. This review highlights current knowledge from preclinical and clinical studies examining the role of PTHrP in promoting tumor progression as well as skeletal and soft tissue metastasis, especially with regards to the protein as a regulator of tumor dormancy. The discussion will also provide perspectives on PTHrP as a prognostic factor and therapeutic target to inhibit tumor progression, prevent tumor recurrence, and improve patient survival.
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Affiliation(s)
- Courtney M Edwards
- Program in Cancer Biology, Vanderbilt University, Nashville, TN, United States.,Vanderbilt Center for Bone Biology, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Rachelle W Johnson
- Program in Cancer Biology, Vanderbilt University, Nashville, TN, United States.,Vanderbilt Center for Bone Biology, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, United States.,Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, United States
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Liu Y, Wang Q, Wang Q, Cui M, Jin Y, Wang R, Mao Z, Miao D, Karaplis AC, Zhang YP, Shields LBE, Shields CB, Zhang Y. Role of PTHrP nuclear localization and carboxyl terminus sequences in postnatal spinal cord development. Dev Neurobiol 2020; 81:47-62. [PMID: 33275829 DOI: 10.1002/dneu.22798] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 08/10/2020] [Accepted: 11/27/2020] [Indexed: 11/10/2022]
Abstract
Parathyroid hormone-related peptide (PTHrP) acts under physiological conditions to regulate normal development of several tissues and organs. The role of PTHrP in spinal cord development has not been characterized. Pthrp knock in (Pthrp KI) mice were genetically modified to produce PTHrP in which there is a deficiency of the nuclear localization sequence (NLS) and C-terminus. Using this genetically modified mouse model, we have characterized its effect on spinal cord development early postnatally. The spinal cords from Pthrp KI mice displayed a significant reduction in its length, weight, and cross-sectional area compared to wild-type controls. Histologically, there was a decreased development of neurons and glial cells that caused decreased cell proliferation and increased apoptosis. The neural stem cells (NSCs) cultures also revealed decreased cell proliferation and differentiation and increased apoptosis. The proposed mechanism of delayed spinal cord development in Pthrp KI mice may be due to alteration in associated pathways in regulation of cell-division cycles and apoptosis. There was significant downregulation of Bmi-1 and upregulation of cyclin-dependent kinase inhibitors p27, p21, and p16 in Pthrp KI animals. We conclude that NLS and C-terminus peptide segments of PTHrP play an important role in inhibiting cell apoptosis and stimulation of cellular proliferation necessary for normal spinal cord development.
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Affiliation(s)
- Yahong Liu
- Department of Human Anatomy, Nanjing Medical University, Nanjing, P.R. China
| | - Qiangcheng Wang
- The First Medical School of Nanjing Medical University, Nanjing Medical University, Nanjing, P.R. China
| | - Qun Wang
- Department of Human Anatomy, Nanjing Medical University, Nanjing, P.R. China
| | - Min Cui
- Department of Human Anatomy, Nanjing Medical University, Nanjing, P.R. China
| | - Yaoyao Jin
- Department of Human Anatomy, Nanjing Medical University, Nanjing, P.R. China
| | - Rong Wang
- Department of Human Anatomy, Nanjing Medical University, Nanjing, P.R. China.,Key Laboratory for Aging & Diseases of Nanjing Medical University, Nanjing Medical University, Nanjing, P.R. China
| | - Zhiyuan Mao
- Department of Human Anatomy, Nanjing Medical University, Nanjing, P.R. China.,Key Laboratory for Aging & Diseases of Nanjing Medical University, Nanjing Medical University, Nanjing, P.R. China
| | - Dengshun Miao
- Department of Human Anatomy, Nanjing Medical University, Nanjing, P.R. China.,Key Laboratory for Aging & Diseases of Nanjing Medical University, Nanjing Medical University, Nanjing, P.R. China
| | - Andrew C Karaplis
- Department of Medicine, McGill University, McGill University Health Centre, Montreal, QC, Canada
| | - Yi Ping Zhang
- Norton Neuroscience Institute, Norton Healthcare, Louisville, KY, USA
| | - Lisa B E Shields
- Norton Neuroscience Institute, Norton Healthcare, Louisville, KY, USA
| | | | - Yongjie Zhang
- Department of Human Anatomy, Nanjing Medical University, Nanjing, P.R. China.,Key Laboratory for Aging & Diseases of Nanjing Medical University, Nanjing Medical University, Nanjing, P.R. China
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Kim JH, Yamaori S, Tanabe T, Takagi M, Matsubara T, Okamoto M, Kimura S, Gonzalez FJ. Lack of epithelial PPARγ causes cystic adenomatoid malformations in mouse fetal lung. Biochem Biophys Res Commun 2017; 491:271-276. [PMID: 28739257 DOI: 10.1016/j.bbrc.2017.07.113] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 07/20/2017] [Indexed: 12/15/2022]
Abstract
Peroxisome proliferator-activated receptor-γ (PPARγ) plays an important role in lipid and glucose metabolism. In this study, the function of PPARγ on lung development was investigated. Lung-specific Pparg conditional knockout mice (PpargΔLuEpC) were developed using Cre-Lox system. PpargΔLuEpC mice showed abnormal lung development with enlarged airspaces and followed by increase of apoptotic cells at E14.5 to E18.5. Gene analysis revealed that expression of Pmaip1, a gene related to apoptosis, was significantly increased while expression of Retnla, a gene related to anti-apoptosis, was dramatically decreased in the fetal lung (E14.5) of PpargΔLuEpC mice. In addition, expression of Pthlh, a gene phenotypically expressed in the congenital cystic adenomatoid malformation (CCAM), was increased at E14.5 to E18.5 in the lung of PpargΔLuEpC mice. Cell culture studies revealed that PPARγ could bind to promoter region of Pthlh gene as a repressor in the immortalized mouse lung epithelial cell line MLE-15. Surprisingly, phenotypic changes in MLE-15-shPparg cells, stably transfected with shPparg plasmid, were similar to the PpargΔLuEpC mice model. In addition, MLE-15-shPparg cells were easily detached from the cultured plate when cold phosphate buffered saline was applied. Furthermore, expression of Cdh1, a gene related to cell adhesion, was significantly reduced in the MLE-15-shPparg cells. Taken together, PPARγ may play an important role in fetal lung development via alveolar cell-to-cell adhesion system.
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Affiliation(s)
- Jung-Hwan Kim
- Department of Pharmacology, School of Medicine, Institute of Health Sciences, Gyeongsang National University, Jinju 52727, Republic of Korea; Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Satoshi Yamaori
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Tomotaka Tanabe
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Mitsuhiro Takagi
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Tsutomu Matsubara
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Minoru Okamoto
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Shioko Kimura
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Frank J Gonzalez
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
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Lung carcinoma progression and survival versus amino- and carboxyl-parathyroid hormone-related protein expression. J Cancer Res Clin Oncol 2017; 143:1395-1407. [PMID: 28342003 DOI: 10.1007/s00432-017-2396-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2016] [Accepted: 03/14/2017] [Indexed: 01/22/2023]
Abstract
PURPOSE Expression of the carboxyl PTHrP region of parathyroid hormone-related protein (PTHrP) is a positive prognostic indicator in women with lung cancer, but amino PTHrP is a negative indicator in other lung cancer patients. This project investigated whether PTHrP could be expressed as predominantly amino PTHrP or carboxyl PTHrP in individual lung carcinomas. It also assessed domain-specific effects on cancer progression and patient survival. METHODS PTHrP immunoreactivities were analyzed versus survival in a human lung cancer tissue microarray (TMA). Growth was compared in athymic mice for isogenic lung carcinoma xenografts differing in expression of amino and carboxyl PTHrP domains. RESULTS In the TMA, 33 of 99 patient tumors expressed only one PTHrP domain, while 54 expressed both. By Cox regression, the hazard ratio for cancer-specific mortality (95% confidence interval) was 2.6 (1.28-5.44) for amino PTHrP (P = 0.008) and 0.6 (0-2.58) for carboxyl PTHrP (P = 0.092). Xenografts of H358 lung adenocarcinoma cells that overexpressed amino PTHrP grew twice as fast as isogenic low PTHrP tumors in athymic mice, but growth of tumors expressing amino plus carboxyl PTHrP was not significantly different than growth of the control tumors. In summary, the presence of amino PTHrP signifies worse prognosis in lung cancer patients. In mouse xenografts, this effect was abrogated if carboxyl PTHrP was also present. CONCLUSION Amino PTHrP and carboxyl PTHrP can vary independently in different lung carcinomas. Carboxyl PTHrP may temper the stimulatory effect of amino PTHrP on cancer progression.
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Xu C, Wang Z, Cui R, He H, Lin X, Sheng Y, Zhang H. Co-expression of parathyroid hormone related protein and TGF-beta in breast cancer predicts poor survival outcome. BMC Cancer 2015; 15:925. [PMID: 26597083 PMCID: PMC4655491 DOI: 10.1186/s12885-015-1873-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 10/30/2015] [Indexed: 02/06/2023] Open
Abstract
Background Better methods to predict prognosis can play a supplementary role in administering individualized treatment for breast cancer patients. Altered expressions of PTHrP and TGF-β have been observed in various types of human cancers. The objective of the current study was to evaluate the association of PTHrP and TGF-β level with the clinicopathological features of the breast cancer patients. Methods Immunohistochemistry was used to examine PTHrP and TGF-β protein expression in 497 cases of early breast cancer, and Kaplan-Meier method and COX’s Proportional Hazard Model were applied to the prognostic value of PTHrP and TGF-β expression. Results Both over-expressed TGF-β and PTHrP were correlated with the tumor in larger size, higher proportion of axillary lymph node metastasis and later clinical stage. Additionally, the tumors with a high TGF-β level developed poor differentiation, and only TGF-β expression was associated with disease-free survival (DFS) of the breast cancer patients. Followed up for a median of 48 months, it was found that only the patients with negative TGF-β expression had longer DFS (P < 0.05, log-rank test). Nevertheless, those with higher PTHrP expression tended to show a higher rate of bone metastasis (67.6 % vs. 45.8 %, P = 0.019). In ER negative subgroup, those who developed PTHrP positive expression presented poor prognosis (P < 0.05, log-rank test). The patients with both positive TGF-β and PTHrP expression were significantly associated with the high risk of metastases. As indicated by Cox’s regression analysis, TGF-β expression and the high proportion of axillary lymph node metastasis served as significant independent predictors for breast cancer recurrence. Conclusions TGF-β and PTHrP were confirmed to be involved in regulating the malignant progression in breast cancer, and PTHrP expression, to be associated with bone metastasis as a potential prognostic marker in ER negative breast cancer.
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Affiliation(s)
- Cheng Xu
- Department of Breast Surgery, Yangpu Hospital, Tongji University School of Medicine, Shanghai, 200090, China.
| | - Zhengyuan Wang
- Department of Breast Surgery, Yangpu Hospital, Tongji University School of Medicine, Shanghai, 200090, China.
| | - Rongrong Cui
- Department of Breast Surgery, Yangpu Hospital, Tongji University School of Medicine, Shanghai, 200090, China.
| | - Hongyu He
- Department of Intensive Care Medicine, Zhongshan Hospital, Fudan University, Shanghai, 200032, China.
| | - Xiaoyan Lin
- Department of Breast Surgery, Yangpu Hospital, Tongji University School of Medicine, Shanghai, 200090, China.
| | - Yuan Sheng
- Department of Thyroid and Breast Surgery, Changhai Hospital, Shanghai, 200433, China.
| | - Hongwei Zhang
- Department of General Surgery, Zhongshan Hospital, Fudan University, Shanghai, 200032, China.
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Montgrain PR, Phun J, Vander Werff R, Quintana RA, Davani AJ, Hastings RH. Parathyroid-hormone-related protein signaling mechanisms in lung carcinoma growth inhibition. SPRINGERPLUS 2015; 4:268. [PMID: 26090315 PMCID: PMC4469590 DOI: 10.1186/s40064-015-1017-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 05/08/2015] [Indexed: 11/11/2022]
Abstract
Parathyroid hormone-related protein (PTHrP) inhibits proliferation of several lung cancer cell lines, but the signaling mechanism has not been established. This study tested the hypotheses that growth inhibition is mediated through the PTHrP receptor, PTH1R, and that the process is modified by ERK activation. PTHrP-positive and negative clones of H1944 lung adenocarcinoma cells underwent stable PTH1R knockdown with lentiviral shRNA or transient transfection with ERK1 and ERK2 siRNA. Alternatively, cells were treated with 8-CPT cAMP, 8-CPT 2′-O-methyl cAMP, and N-6-phenyl cAMP analogs. H1944 cells expressing ectopic PTHrP showed 20–40% decrease in proliferation compared to the PTHrP-negative cells in the presence of normal levels of PTH1R (P < 0.01). PTH1R knockdown eliminated this difference and increased cell proliferation regardless of PTHrP status. The three cAMP analogs each inhibited proliferation over 5 days by 30–40%. ERK2 knockdown inhibited proliferation of PTHrP-positive cells alone and in combination with ERK1 knockdown. The growth inhibition mediated by cAMP analogs was unaffected by ERK1 knockdown. In conclusion, ectopic expression of PTHrP 1–87 inhibits H1944 cell proliferation. PTH1R knockdown blocks this effect and stimulates proliferation, indicating that the ligand exerts anti-mitogenic effects. cAMP, the second messenger for PTH1R also inhibits proliferation and activates ERK. PTHrP growth inhibition may be opposed by concomitant ERK activation.
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Affiliation(s)
- Philippe R Montgrain
- Medicine Service, Pulmonary and Critical Care Division, Department of Medicine, VA San Diego Healthcare System, UC San Diego, San Diego, USA
| | - Jennifer Phun
- Research Service, Department of Biology, VA San Diego Healthcare System, UC San Diego, San Diego, USA
| | - Ryan Vander Werff
- Research Service, Department of Biology, VA San Diego Healthcare System, UC San Diego, San Diego, USA
| | - Rick A Quintana
- Research Service, VA San Diego Healthcare System, San Diego, USA
| | - Ariea J Davani
- Research Service, VA San Diego Healthcare System, San Diego, USA
| | - Randolph H Hastings
- Anesthesiology Service, Department of Anesthesiology, VA Medical Center (125), VA San Diego Healthcare System, UC San Diego, 3350 La Jolla Village Dr., San Diego, CA 92161 USA
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Montgrain PR, Deftos LJ, Arenberg D, Tipps A, Quintana R, Carskadon S, Hastings RH. Prognostic implications of parathyroid hormone-related protein in males and females with non--small-cell lung cancer. Clin Lung Cancer 2011; 12:197-205. [PMID: 21663864 DOI: 10.1016/j.cllc.2011.03.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2010] [Revised: 09/13/2010] [Accepted: 09/21/2010] [Indexed: 01/23/2023]
Abstract
BACKGROUND Non-small-cell lung carcinoma immunoreactivity for parathyroid hormone-related protein has been associated with increased survival in female patients but not in male patients. The current investigation attempted to substantiate this finding in 2 new patient groups. METHODS Patients were divided into groups with and without immunoreactivity for a carboxyl-terminal parathyroid hormone-related protein epitope assessed in deparaffinized sections by a blinded observer. One group included 85 female patients with stage I lung cancer, and the second group had 48 female and 66 male patients with stage I-IV lung cancer. Survival times were compared by the log-rank test between groups separated by tumor parathyroid hormone-related protein status. RESULTS Parathyroid hormone-related protein was present in 70%-80% of the patients, independent of sex, stage, and smoking history. In the females with stage I lung cancer, parathyroid hormone-related protein increased median survival from 25 to 60 months (P < .05). In the second group, parathyroid hormone-related protein expression increased 48-month disease-free survival of female lung cancer patients from 44% to 63% (P < .05), but had no effect in male patients. Parathyroid hormone-related protein remained a significant, independent predictor when evaluated together with other covariates by Cox multivariate regression. CONCLUSION This study verifies that parathyroid hormone-related protein is a sex-dependent survival factor for non-small-cell lung carcinoma, that it correlates with disease-free survival, and that the association with survival holds for women with early-stage disease as well as more advanced cancer. Thus, the protein could find use as a prognostic indicator and could be a target for therapy.
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Affiliation(s)
- Philippe R Montgrain
- Research, Anesthesiology and Medicine Services, VA San Diego Healthcare System, San Diego, CA 92161, USA
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Luparello C. Parathyroid Hormone-Related Protein (PTHrP): A Key Regulator of Life/Death Decisions by Tumor Cells with Potential Clinical Applications. Cancers (Basel) 2011; 3:396-407. [PMID: 24212621 PMCID: PMC3756367 DOI: 10.3390/cancers3010396] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Revised: 12/27/2010] [Accepted: 01/14/2011] [Indexed: 11/16/2022] Open
Abstract
Parathyroid hormone-related protein (PTHrP), classically regarded as the mediator of the humoral hypercalcemia of malignancy syndrome, is a polyhormone that undergoes proteolytic processing into smaller bioactive forms. These bioactive forms comprise an N-terminal- as well as midregion- and C-terminal peptides, which have been shown to regulate various biological events, such as survival, proliferation and differentiation, in diverse cell model systems, both normal and pathological. A number of experimental data have demonstrated that PTHrP is also able to modulate tumor-relevant phenotypic expressions, thereby playing a role in early and advanced tumorigenesis, and in the response to treatment. In particular, interest has mainly been focused on the effects of PTHrP on cell proliferation/apoptosis, migration and invasion, which are the main roles involved in cancer development in vivo. The objective of this review is to discuss collectively the literature data on the molecular and biochemical basis of the mechanisms underlying the different, and sometimes opposite, effects exerted by PTHrP on various neoplastic cytotypes, with some final comments on both present and potential utilization of PTHrP as a target for anti-cancer therapy.
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Affiliation(s)
- Claudio Luparello
- Dipartimento di Biologia Cellulare e dello Sviluppo, Università di Palermo, Viale delle Scienze, 90128 Palermo, Italy.
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