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He Z, Peng B, Wang Q, Tian J, Liu P, Feng J, Liao Y, Chen L, Jia P, Tang J. Transcriptomic analysis identifies the neuropeptide cortistatin (CORT) as an inhibitor of temozolomide (TMZ) resistance by suppressing the NF-κB-MGMT signaling axis in human glioma. Genes Dis 2024; 11:100977. [PMID: 38292193 PMCID: PMC10825237 DOI: 10.1016/j.gendis.2023.04.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 03/19/2023] [Accepted: 04/02/2023] [Indexed: 02/01/2024] Open
Abstract
Glioma is a common tumor originating in the brain that has a high mortality rate. Temozolomide (TMZ) is the first-line treatment for high-grade gliomas. However, a large proportion of gliomas are resistant to TMZ, posing a great challenge to their treatment. In the study, the specific functions and mechanism(s) by which cortistatin (CORT) regulates TMZ resistance and glioma progression were evaluated. The decreased expression of CORT was detected in glioma tissues, and highly expressed CORT was associated with a better survival rate in patients with glioma. CORT overexpression notably decreased the capacity of glioma cells to proliferate and migrate in vitro and to form tumors in vivo. CORT overexpression also markedly suppressed the viability and enhanced the apoptosis of TMZ-resistant U251 cells by regulating MGMT, p21, and Puma expression. Importantly, CORT overexpression reduced the resistance of gliomas to TMZ in vivo. CORT expression was negatively correlated with MGMT expression in both glioma tissues and cells, and it was found that CORT inhibited NF-κB pathway activation in glioma cells, thereby inhibiting MGMT expression. In conclusion, CORT regulates glioma cell growth, migration, apoptosis, and TMZ resistance by weakening the activity of NF-κB/p65 and thereby regulating MGMT expression. The CORT/NF-κB/MGMT axis might be regarded as a molecular mechanism contributing to the resistance of glioma to TMZ. Our data also suggest that CORT regulates the viability and metastatic potential of glioma cells, independent of its effects on TMZ resistance, providing evidence of novel therapeutic targets for glioma that should be evaluated in further studies.
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Affiliation(s)
- Zongze He
- Department of Neurosurgery, Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, Sichuan 610072, China
| | - Bo Peng
- Department of Rehabilitation Medicine, Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, Sichuan 610072, China
| | - Qi Wang
- Department of Neurosurgery, Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, Sichuan 610072, China
| | - Jie Tian
- Department of Neurosurgery, Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, Sichuan 610072, China
| | - Ping Liu
- Department of Neurosurgery, Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, Sichuan 610072, China
| | - Jie Feng
- Department of Neurosurgery, Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, Sichuan 610072, China
| | - Yiwei Liao
- Department of Neurosurgery, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China
| | - Longyi Chen
- Department of Neurosurgery, Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, Sichuan 610072, China
| | - Ping Jia
- Department of Neurosurgery, Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, Sichuan 610072, China
| | - Jian Tang
- Department of Neurosurgery, Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, Sichuan 610072, China
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Kumar U. Somatostatin and Somatostatin Receptors in Tumour Biology. Int J Mol Sci 2023; 25:436. [PMID: 38203605 PMCID: PMC10779198 DOI: 10.3390/ijms25010436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 12/24/2023] [Accepted: 12/25/2023] [Indexed: 01/12/2024] Open
Abstract
Somatostatin (SST), a growth hormone inhibitory peptide, is expressed in endocrine and non-endocrine tissues, immune cells and the central nervous system (CNS). Post-release from secretory or immune cells, the first most appreciated role that SST exhibits is the antiproliferative effect in target tissue that served as a potential therapeutic intervention in various tumours of different origins. The SST-mediated in vivo and/or in vitro antiproliferative effect in the tumour is considered direct via activation of five different somatostatin receptor subtypes (SSTR1-5), which are well expressed in most tumours and often more than one receptor in a single cell. Second, the indirect effect is associated with the regulation of growth factors. SSTR subtypes are crucial in tumour diagnosis and prognosis. In this review, with the recent development of new SST analogues and receptor-specific agonists with emerging functional consequences of signaling pathways are promising therapeutic avenues in tumours of different origins that are discussed.
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Affiliation(s)
- Ujendra Kumar
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, BC V6T 1Z3, Canada
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3
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Wan Z, Wang X. Role of SLC39A6 in the development and progression of liver cancer. Oncol Lett 2022; 23:77. [PMID: 35111246 PMCID: PMC8771636 DOI: 10.3892/ol.2022.13197] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 12/21/2021] [Indexed: 12/11/2022] Open
Abstract
Liver cancer is one of the most common malignant solid tumor types worldwide. The solute carrier (SLC)39A family is a main member of the SLC group of membrane transport proteins, which transfer zinc to the cytoplasm when cells are depleted of zinc; thus, it may provide a novel therapeutic target for human cancer. However, the prognostic value of SLC39A genes in patients with liver cancer has remained elusive. Therefore, the present study aimed to explore whether SLC39A family genes are associated with the survival rate of patients with liver cancer and to investigate the role of key genes of the SLC39A family in liver cancer. The mRNA expression of the SLC39A family in liver cancer was obtained from the UALCAN database. Survival curve analysis was performed to investigate the prognostic value of SLC39A family genes in the overall survival of patients with liver cancer. In addition to the bioinformatics analysis, SLC39A6 was knocked down in HepG2 and Hep3B cells to examine the effect on the proliferation, migration and invasion of liver cancer cells. The results suggested that SLC39A6 was significantly upregulated in liver cancer tissues compared with normal liver tissues. High expression of SLC39A6 was significantly associated with poor overall survival of patients with liver cancer. Furthermore, knockdown of SLC39A6 inhibited the proliferation, migration and invasion of liver cancer cells in vitro and in vivo. Collectively, the results of the present study suggested that SLC39A6 may be a promising prognostic biomarker for liver cancer and is associated with the proliferation, migration and invasion of liver cancer.
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Affiliation(s)
- Zhen Wan
- Department of General Surgery, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China
| | - Xuzhen Wang
- Department of Critical Care Medicine, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China
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Zhang HY, Xu WQ, Zheng YY, Omari-Siaw E, Zhu Y, Cao X, Tong SS, Yu JN, Xu XM. Octreotide-periplocymarin conjugate prodrug for improving targetability and anti-tumor efficiency: synthesis, in vitro and in vivo evaluation. Oncotarget 2018; 7:86326-86338. [PMID: 27861145 PMCID: PMC5349917 DOI: 10.18632/oncotarget.13389] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Accepted: 11/09/2016] [Indexed: 01/01/2023] Open
Abstract
Cardiac glycosides could increase intracellular Ca2+ ion by inhibiting the Na+/K+ATPase to induce apoptosis in many tumor cells. However, narrow therapeutic index, poor tumor selectivity and severe cardiovascular toxicity hinder their applications in cancer treatment. To improve the safety profile and tumor targetablility of cardiac glycosides, we designed octreotide conjugated periplocymarin, a cardiac glycoside isolated from Cortex periplocae. The conjugate showed higher cytotoxicity on MCF-7 cells and HepG2 tumor cells (SSTRs overexpression) but much less toxicity in L-02 normal cells. Tissue distribution studies of the conjugate using H22 tumor model in mice showed higher accumulation in tumor and lower distribution in heart and liver than periplocymarin. Furthermore, in vivo anticancer effects of the conjugate on mice bearing H22 cancer xenografts confirmed enhanced anti-tumor efficacy and decreased systemic toxicity. Altogether, octreotide-conjugated periplocymarin demonstrated tumor selectivity and may be useful as a targeting agent to improve the safety profile of cardiac glycosides for cancer therapy.
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Affiliation(s)
- Hui-Yun Zhang
- Department of Pharmaceutics, School of Pharmacy, Center for Nano Drug/Gene Delivery and Tissue Engineering, Jiangsu University, Zhenjiang, People's Republic of China
| | - Wen-Qian Xu
- Department of Pharmaceutics, School of Pharmacy, Center for Nano Drug/Gene Delivery and Tissue Engineering, Jiangsu University, Zhenjiang, People's Republic of China
| | - Yuan-Yuan Zheng
- School of Pharmacy, China Pharmaceutical University, Nanjing, People's Republic of China
| | - Emmanuel Omari-Siaw
- Department of Pharmaceutics, School of Pharmacy, Center for Nano Drug/Gene Delivery and Tissue Engineering, Jiangsu University, Zhenjiang, People's Republic of China
| | - Yuan Zhu
- Department of Pharmaceutics, School of Pharmacy, Center for Nano Drug/Gene Delivery and Tissue Engineering, Jiangsu University, Zhenjiang, People's Republic of China
| | - Xia Cao
- Department of Pharmaceutics, School of Pharmacy, Center for Nano Drug/Gene Delivery and Tissue Engineering, Jiangsu University, Zhenjiang, People's Republic of China
| | - Shan-Shan Tong
- Department of Pharmaceutics, School of Pharmacy, Center for Nano Drug/Gene Delivery and Tissue Engineering, Jiangsu University, Zhenjiang, People's Republic of China
| | - Jiang-Nan Yu
- Department of Pharmaceutics, School of Pharmacy, Center for Nano Drug/Gene Delivery and Tissue Engineering, Jiangsu University, Zhenjiang, People's Republic of China.,School of Pharmacy, China Pharmaceutical University, Nanjing, People's Republic of China
| | - Xi-Ming Xu
- Department of Pharmaceutics, School of Pharmacy, Center for Nano Drug/Gene Delivery and Tissue Engineering, Jiangsu University, Zhenjiang, People's Republic of China
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Kaemmerer D, Schindler R, Mußbach F, Dahmen U, Altendorf-Hofmann A, Dirsch O, Sänger J, Schulz S, Lupp A. Somatostatin and CXCR4 chemokine receptor expression in hepatocellular and cholangiocellular carcinomas: tumor capillaries as promising targets. BMC Cancer 2017; 17:896. [PMID: 29282035 PMCID: PMC5745780 DOI: 10.1186/s12885-017-3911-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 12/13/2017] [Indexed: 12/15/2022] Open
Abstract
Background Hepatocellular (HCC) and cholangiocellular carcinomas (CCC) display an exceptionally poor prognosis. Especially for advanced disease no efficient standard therapy is currently available. Recently, somatostatin analogs have been evaluated for the treatment of HCC, however, with contradictory results. Besides, for both malignancies the chemokine receptor CXCR4 has been discussed as a possible new target structure. Methods Expression of somatostatin receptor (SSTR) subtypes 1, 2A, 3, 4, and 5, and of CXCR4 was evaluated in a total of 71 HCCs and 27 CCCs by immunohistochemistry using well-characterized novel monoclonal antibodies. Results In HCC tumor cells, frequency and intensity of expression of SSTRs and CXCR4 were only low. CXCR4 was present in about 40% of the HCCs, although at a low intensity. SSTR5, SSTR2, and SSTR3 were detected in about 15%, 8%, and 5% of the HCC tumors, respectively. SSTR and CXCR4 expression was much higher in CCC than in HCC. CXCR4 and SSTR1 were present in 60% and 67% of the CCC samples, respectively, followed by SSTR2 and SSTR5, which were detected in 30% and 11% of the tumors, respectively. Most notably, CXCR4 was intensely expressed on the tumor capillaries in about 50% of the HCCs and CCCs. CXCR4 expression on tumor vessels was associated with poor patient outcomes. Conclusions CCC, but not HCC, may be suitable for SSTR-based treatments. Because of the predominant expression of SSTR1, pan-somatostatin analogs should be preferred. In both HCC and CCC, indirect targeting of tumors via the CXCR4-positive tumor capillaries may represent a promising additional therapeutic strategy. Electronic supplementary material The online version of this article (10.1186/s12885-017-3911-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Daniel Kaemmerer
- Department of General and Visceral Surgery, Zentralklinik Bad Berka, Bad Berka, Germany
| | - Robin Schindler
- Institute of Pharmacology and Toxicology, Jena University Hospital, Friedrich Schiller University Jena, Drackendorfer Str. 1, D-07747, Jena, Germany
| | - Franziska Mußbach
- Department of General, Visceral and Vascular Surgery, Jena University Hospital, Jena, Germany
| | - Uta Dahmen
- Department of General, Visceral and Vascular Surgery, Jena University Hospital, Jena, Germany
| | | | - Olaf Dirsch
- Institute of Pathology, Jena University Hospital, Jena, Germany
| | - Jörg Sänger
- Institute of Pathology and Cytology Bad Berka, Bad Berka, Germany
| | - Stefan Schulz
- Institute of Pharmacology and Toxicology, Jena University Hospital, Friedrich Schiller University Jena, Drackendorfer Str. 1, D-07747, Jena, Germany
| | - Amelie Lupp
- Institute of Pharmacology and Toxicology, Jena University Hospital, Friedrich Schiller University Jena, Drackendorfer Str. 1, D-07747, Jena, Germany.
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Zhang HY, Xu WQ, Wang YW, Omari-Siaw E, Wang Y, Zheng YY, Cao X, Tong SS, Yu JN, Xu XM. Tumor targeted delivery of octreotide-periplogenin conjugate: Synthesis, in vitro and in vivo evaluation. Int J Pharm 2016; 502:98-106. [PMID: 26899980 DOI: 10.1016/j.ijpharm.2016.02.024] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Revised: 02/01/2016] [Accepted: 02/14/2016] [Indexed: 12/17/2022]
Abstract
Periplogenin (PPG), a cardiac glycoside prepared from Cortex periplocae, with similar structure to bufalin, has been found to induce apoptosis in many tumor cells. However, lots of cardiac glycosides possessing strong antitumor activity in vitro have still not passed phase I clinical trials, mostly due to poor tumor selectivity and systemic toxicity. To overcome this drawback, we designed octreotide-periplogenin (OCT-PPG) conjugate by coupling PPG-succinate to the amino-terminal end of octreotide. In comparison with free PPG, the conjugate exhibited significantly stronger cytotoxicity on HepG2 cells (SSTRs overexpression) but much less toxicity in L-02 cells. After intravenous injection of OCT-PPG conjugate into H22 tumor-bearing mice, its total accumulation in tumor was 2.3 fold higher than that of free PPG, but was 0.71- and 0.84-fold lower in heart and liver, respectively, suggesting somatostatin-mediated target delivery of PPG into the tumor tissue and reduced distribution in heart and liver. In vivo studies using H22 tumor model in mice confirmed the remarkable therapeutic effect of this conjugate. These results suggested that OCT-PPG conjugate could provide a new approach for clinical application of cardiac glycosides and as a targeting agent for cancer therapy.
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Affiliation(s)
- Hui-Yun Zhang
- Department of Pharmaceutics, School of Pharmacy, Center for Nano Drug/Gene Delivery and Tissue Engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China
| | - Wen-Qian Xu
- Department of Pharmaceutics, School of Pharmacy, Center for Nano Drug/Gene Delivery and Tissue Engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China
| | - Yuan-Wen Wang
- Department of Pharmaceutics, School of Pharmacy, Center for Nano Drug/Gene Delivery and Tissue Engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China
| | - Emmanuel Omari-Siaw
- Department of Pharmaceutics, School of Pharmacy, Center for Nano Drug/Gene Delivery and Tissue Engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China
| | - Yan Wang
- Department of Pharmaceutics, School of Pharmacy, Center for Nano Drug/Gene Delivery and Tissue Engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China
| | - Yuan-Yuan Zheng
- School of Pharmacy, China Pharmaceutical University, Nanjing, People's Republic of China
| | - Xia Cao
- Department of Pharmaceutics, School of Pharmacy, Center for Nano Drug/Gene Delivery and Tissue Engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China
| | - Shan-Shan Tong
- Department of Pharmaceutics, School of Pharmacy, Center for Nano Drug/Gene Delivery and Tissue Engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China
| | - Jiang-Nan Yu
- Department of Pharmaceutics, School of Pharmacy, Center for Nano Drug/Gene Delivery and Tissue Engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China; School of Pharmacy, China Pharmaceutical University, Nanjing, People's Republic of China.
| | - Xi-Ming Xu
- Department of Pharmaceutics, School of Pharmacy, Center for Nano Drug/Gene Delivery and Tissue Engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China.
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Drug delivery system targeting advanced hepatocellular carcinoma: Current and future. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2016; 12:853-869. [PMID: 26772424 DOI: 10.1016/j.nano.2015.12.381] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Revised: 12/16/2015] [Accepted: 12/22/2015] [Indexed: 12/21/2022]
Abstract
UNLABELLED Hepatocellular carcinoma (HCC) has a fairly high morbidity and is notoriously difficult to treat due to long latent period before detection, multidrug resistance and severe drug-related adverse effects from chemotherapy. Targeted drug delivery systems (DDS) that can selectively deliver therapeutic drugs into tumor sites have demonstrated a great potential in cancer treatment, which could be utilized to resolve the limitations of conventional chemotherapy. Numerous preclinical studies of DDS have been published, but targeted DDS for HCC has yet to be made for practical clinical use. Since rational targeted DDS design should take cancer-specific properties into consideration, we have reviewed the biological and physicochemical properties of HCC extensively to provide a comprehensive understanding on HCC, and recent DDS studies on HCC, aiming to find some potential targeted DDSs for HCC treatment and a meaningful platform for further development of HCC treatments. FROM THE CLINICAL EDITOR Hepatocellular carcinoma has a high incidence worldwide and is known to be multidrug resistant. Thus, intensive research is being carried out to find better chemotherapeutic agents as well as new drug delivery systems. In this article, the authors reviewed in depth the current challenges facing new drug designs and also outlined novel targeted drug delivery systems (DDS) in the fight against HCC.
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Pivonello C, De Martino MC, Negri M, Cuomo G, Cariati F, Izzo F, Colao A, Pivonello R. The GH-IGF-SST system in hepatocellular carcinoma: biological and molecular pathogenetic mechanisms and therapeutic targets. Infect Agent Cancer 2014; 9:27. [PMID: 25225571 PMCID: PMC4164328 DOI: 10.1186/1750-9378-9-27] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Accepted: 06/23/2014] [Indexed: 12/15/2022] Open
Abstract
Hepatocellular carcinoma (HCC) is the sixth most common malignancy worldwide. Different signalling pathways have been identified to be implicated in the pathogenesis of HCC; among these, GH, IGF and somatostatin (SST) pathways have emerged as some of the major pathways implicated in the development of HCC. Physiologically, GH-IGF-SST system plays a crucial role in liver growth and development since GH induces IGF1 and IGF2 secretion and the expression of their receptors, involved in hepatocytes cell proliferation, differentiation and metabolism. On the other hand, somatostatin receptors (SSTRs) are exclusively present on the biliary tract. Importantly, the GH-IGF-SST system components have been indicated as regulators of hepatocarcinogenesis. Reduction of GH binding affinity to GH receptor, decreased serum IGF1 and increased serum IGF2 production, overexpression of IGF1 receptor, loss of function of IGF2 receptor and appearance of SSTRs are frequently observed in human HCC. In particular, recently, many studies have evaluated the correlation between increased levels of IGF1 receptors and liver diseases and the oncogenic role of IGF2 and its involvement in angiogenesis, migration and, consequently, in tumour progression. SST directly or indirectly influences tumour growth and development through the inhibition of cell proliferation and secretion and induction of apoptosis, even though SST role in hepatocarcinogenesis is still opened to argument. This review addresses the present evidences suggesting a role of the GH-IGF-SST system in the development and progression of HCC, and describes the therapeutic perspectives, based on the targeting of GH-IGF-SST system, which have been hypothesised and experimented in HCC.
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Affiliation(s)
- Claudia Pivonello
- Dipartimento di Medicina Clinica e Chirurgia, Università Federico II di Napoli, Via Sergio Pansini, 5, Naples 80131, Italy
| | - Maria Cristina De Martino
- Dipartimento di Medicina Clinica e Chirurgia, Università Federico II di Napoli, Via Sergio Pansini, 5, Naples 80131, Italy
| | - Mariarosaria Negri
- Dipartimento di Medicina Clinica e Chirurgia, Università Federico II di Napoli, Via Sergio Pansini, 5, Naples 80131, Italy
| | | | - Federica Cariati
- Dipartimento di Medicina Clinica e Chirurgia, Università Federico II di Napoli, Via Sergio Pansini, 5, Naples 80131, Italy
| | - Francesco Izzo
- National Cancer Institute G Pascale Foundation, Naples, Italy
| | - Annamaria Colao
- Dipartimento di Medicina Clinica e Chirurgia, Università Federico II di Napoli, Via Sergio Pansini, 5, Naples 80131, Italy
| | - Rosario Pivonello
- Dipartimento di Medicina Clinica e Chirurgia, Università Federico II di Napoli, Via Sergio Pansini, 5, Naples 80131, Italy
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Zou YX, Shen WZ, Liao ST, Liu F, Zheng SQ, Blumberg JB, Chen CYO. Mulberry leaf phenolics ameliorate hyperglycemia-induced oxidative stress and stabilize mitochondrial membrane potential in HepG2 cells. Int J Food Sci Nutr 2014; 65:960-6. [PMID: 25026091 DOI: 10.3109/09637486.2014.940285] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
To investigate the effect of phenolics in mulberry leaves (mulberry leaf phenolics; MLP) on hyperglycemia-induced oxidative stress and mitochondrial membrane potential (ΔΨm) in HepG2 cells; we treated HepG2 with glucose [5.5 (N-Glc) or 50 mmol/L (Hi-Glc)] with or without MLP at 10 or 100 µmol/L gallic acid equivalents and assessed level of reactive oxidant species (ROS), ΔΨm, malondialdehyde (MDA) and nuclear factor-kappaB (NF-κB) activation. Hi-Glc-induced oxidative damage was demonstrated by a series of increase in superoxides (560%, 0.5 h), MDA (400%, 24 h), NF-κB activation (474%, 4 h) and a wild fluctuation of ΔΨm relative to the control cells (p ≤ 0.05). MLP treatments ameliorate Hi-Glc-induced negative effects by a 40% reduction in ROS production, 34-44% reduction in MDA production, over 35% inhibition of NF-κB activation, as well as exert protective effect on HepG2 cells from change in ΔΨm. Our data show that MLP in vitro can protect hepatoctyes from hyperglycemia-induced oxidative damages.
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Affiliation(s)
- Yu-Xiao Zou
- Sericulture & Agri-Food Research Institute, Guangdong Academy of Agricultural Sciences , Guangzhou , PR China and
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Ayiomamitis GD, Notas G, Zaravinos A, Drygiannakis I, Georgiadou M, Sfakianaki O, Mastrodimou N, Thermos K, Kouroumalis E. Effects of octreotide and insulin on colon cancer cellular proliferation and correlation with hTERT activity. Oncoscience 2014; 1:457-67. [PMID: 25594044 PMCID: PMC4284627 DOI: 10.18632/oncoscience.58] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2014] [Accepted: 06/28/2014] [Indexed: 12/15/2022] Open
Abstract
Peptide hormone somatostatin and its receptors have a wide range of physiological functions and play a role in the treatment of numerous human diseases, including colorectal cancer. Octreotide, a synthetic somatostatin-analog peptide, inhibits growth of colonic cancer cells primarily by binding to G-protein coupled receptors and elicits cellular responses through second-messenger systems. Insulin also initiates mitogenic signals in certain cell types. The objective of the present study was to explore the effects of octreotide with or without insulin treatment, on Caco-2 and HT-29 human colon-cancer cell proliferation and to correlate their effects with the activation of telomerase reverse transcriptase (hTERT). The involvement of protein tyrosine phosphatases in the regulation of the anti-proliferative effect of octreotide was also evaluated. Sodium orthovanadate was used to reverse the anti- proliferative effect of octreotide. Telomerase activity was determined for each time point under octreotide and/or insulin treatment. Elevated expression of sst1, sst2 and sst5 was confirmed in both cell lines by RT-PCR. Immunocytochemistry detected sst1, sst2A, sst2B, sst3, sst4 and sst5 protein expression in the membranes of both cell lines. Octreotide inhibited the proliferation of Caco-2 and HT-29 cells in a time and dose-dependent manner. Insulin exerted proliferative effects in Caco-2 cells and octreotide reversed its effect in both cell lines. Sodium orthovanadate suppressed the anti-proliferative effect of octreotide both in Caco-2 and HT-29 cells. Telomerase activity was significantly reduced when Caco-2 cells were exposed to octreotide, under serum-free cultured medium. On the other hand, telomerase attenuation after octreotide treatment could not counteract the actions of insulin on both cells. Our data indicate that the use of octreotide could provide a possible therapeutic approach to the management of certain patients who suffer from colon cancer.
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Affiliation(s)
- Georgios D Ayiomamitis
- Laboratory of Gastroenterology, School of Medicine, University of Crete, Heraklion, Greece ; 2nd Department of Surgery, Tzaneion General Hospital, Piraeus, Greece
| | - George Notas
- Laboratory of Gastroenterology, School of Medicine, University of Crete, Heraklion, Greece ; Laboratory of Experimental Endocrinology, School of Medicine, University of Crete, Heraklion, Greece
| | - Apostolos Zaravinos
- Laboratory of Clinical Virology, School of Medicine, University of Crete, Heraklion, Greece ; Department of Laboratory Medicine, Karolinska Institute, Stockholm, Sweden
| | - Ioannis Drygiannakis
- Laboratory of Gastroenterology, School of Medicine, University of Crete, Heraklion, Greece
| | - Maria Georgiadou
- Laboratory of Gastroenterology, School of Medicine, University of Crete, Heraklion, Greece
| | - Ourania Sfakianaki
- Laboratory of Gastroenterology, School of Medicine, University of Crete, Heraklion, Greece
| | - Niki Mastrodimou
- Laboratory of Pharmacology, School of Medicine, University of Crete, Heraklion, Crete, Greece
| | - Kyriaki Thermos
- Laboratory of Pharmacology, School of Medicine, University of Crete, Heraklion, Crete, Greece
| | - Elias Kouroumalis
- Laboratory of Gastroenterology, School of Medicine, University of Crete, Heraklion, Greece ; Department of Gastroenterology and Hepatology, School of Medicine, University of Crete, Heraklion, Greece
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Somvanshi RK, Kumar U. δ-opioid receptor and somatostatin receptor-4 heterodimerization: possible implications in modulation of pain associated signaling. PLoS One 2014; 9:e85193. [PMID: 24416361 PMCID: PMC3885706 DOI: 10.1371/journal.pone.0085193] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Accepted: 12/01/2013] [Indexed: 01/13/2023] Open
Abstract
Pain relief is the principal action of opioids. Somatostatin (SST), a growth hormone inhibitory peptide is also known to alleviate pain even in cases when opioids fail. Recent studies have shown that mice are prone to sustained pain and devoid of analgesic effect in the absence of somatostatin receptor 4 (SSTR4). In the present study, using brain slices, cultured neurons and HEK-293 cells, we showed that SSTR4 and δ-Opioid receptor (δOR) exist in a heteromeric complex and function in synergistic manner. SSTR4 and δOR co-expressed in cortical/striatal brain regions and spinal cord. Using cultured neuronal cells, we describe the heterogeneous complex formation of SSTR4 and δOR at neuronal cell body and processes. Cotransfected cells display inhibition of cAMP/PKA and co-activation of SSTR4 and δOR oppose receptor trafficking induced by individual receptor activation. Furthermore, downstream signaling pathways either associated with withdrawal or pain relief are modulated synergistically with a predominant role of SSTR4. Inhibition of cAMP/PKA and activation of ERK1/2 are the possible cellular adaptations to prevent withdrawal induced by chronic morphine use. Our results reveal direct intra-membrane interaction between SSTR4 and δOR and provide insights for the molecular mechanism for the anti-nociceptive property of SST in combination with opioids as a potential therapeutic approach to avoid undesirable withdrawal symptoms.
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Affiliation(s)
- Rishi K. Somvanshi
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, Canada
| | - Ujendra Kumar
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, Canada
- * E-mail:
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Gaviglio L, Gross A, Metzler-Nolte N, Ravera M. Synthesis and in vitro cytotoxicity of cis,cis,trans-diamminedichloridodisuccinatoplatinum(IV)-peptide bioconjugates. Metallomics 2012; 4:260-6. [PMID: 22310724 DOI: 10.1039/c2mt00171c] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The synthesis and characterization of four Pt(IV)-peptide conjugates, containing one or two peptides in the axial position, designed for the purpose of targeted drug delivery to tumor cells, are described. The precursor cis,cis,trans-diamminedichloridodisuccinatoplatinum(IV) was coupled in the last step of standard solid-phase peptide synthesis (SSPS) with an analogue of neurotensin (pseudo-neurotensin = Lys-Lys-Pro-Tyr-Ile-Leu) and with octreotate (D-Phe-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-OH), an analogue of somatostatin, respectively. For all peptides, the SSPS reactions afforded both mono- and diconjugated Pt-peptide species, which were separated and purified by RP-HPLC. The two couples of conjugates, together with the precursor, were tested as cytotoxic agents towards different cancer cell lines. In general all conjugates are good inhibitors of cellular proliferation when compared to a nontargeting platinum(IV) parent compound, so that its relatively low cytotoxicity is greatly improved by addition of the peptides.
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Affiliation(s)
- Luca Gaviglio
- Dipartimento di Scienze dell'Ambiente e della Vita, Università del Piemonte Orientale Amedeo Avogadro, Viale T. Michel 11, I-15121 Alessandria, Italy
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Scheele JS, Harder J, Stankovic Z, Räpple D, Dorn A, Spangenberg HC, Blum HE. Clinical response to Auron Misheil Therapy in a man with advanced multifocal hepatocellular carcinoma: A case report. J Med Case Rep 2011; 5:478. [PMID: 21943068 PMCID: PMC3204300 DOI: 10.1186/1752-1947-5-478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2010] [Accepted: 09/24/2011] [Indexed: 11/10/2022] Open
Abstract
Introduction Auron Misheil Therapy was developed based on similarities between carcinogenesis and inflammation. Auron Misheil Therapy is a combination of natural and synthetic compounds, including anti-inflammatory drugs and insulin, expected to exhibit synergistic effects. Case presentation Here, we report the case of a 78-year-old Caucasian male patient who presented with multifocal hepatocellular carcinoma and chronic hepatitis C virus infection. Over a four-year period our patient was treated with radiofrequency ablation and transarterial chemoembolization. After these treatments there was tumor progression, with new hyperperfused lesions without evidence of extrahepatic tumor involvement. Our patient refused sorafenib therapy. Therefore, he received twice daily intramuscular injections of Auron Misheil Therapy on an outpatient basis for two months. Partial remission of the hepatic lesions was observed eight weeks after the start of treatment, and confirmed four weeks later. Unfortunately, at that time our patient refused therapy due to dizziness. During follow-up two target lesions remained stable, but one lesion increased in size. At the latest follow-up, one year later, there was still tumor control. Conclusion While the mechanisms underlying the antitumor effects of Auron Misheil Therapy are not fully understood, stable disease and remissions have been observed in different types of tumors, including hepatocellular carcinoma.
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Affiliation(s)
- Jürgen S Scheele
- Department of Hematology and Oncology, University Medical Center Freiburg, Hugstetter Strasse 55, 79106 Freiburg, Germany.
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Notas G, Nifli AP, Kampa M, Pelekanou V, Alexaki VI, Theodoropoulos P, Vercauteren J, Castanas E. Quercetin accumulates in nuclear structures and triggers specific gene expression in epithelial cells. J Nutr Biochem 2011; 23:656-66. [PMID: 21782406 DOI: 10.1016/j.jnutbio.2011.03.010] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2010] [Revised: 02/25/2011] [Accepted: 03/11/2011] [Indexed: 12/19/2022]
Abstract
Quercetin is a flavonol modifying a number of cell processes in different cell lines. Here, we present evidence that nonconjugated quercetin enters cells possibly via organic anion transporter polypeptides and quickly accumulates in the nucleus where it concentrates at distinct foci. Furthermore, it induces major transcriptional events with a high number of transcripts being modified over time and about 2200 transcripts being continuously influenced by the agent. The latter transcripts are related to cell cycle and adhesion, xenobiotic metabolism, immune-related factors and transcription. In addition, quercetin up-regulates the expression of estrogen receptors α and β. The overall outcome on cell fate is reflected by an inhibition of cell proliferation, cell cycle arrest in the G1 phase and reduction of the cells' migratory potential due to actin cytoskeleton disorganization. Finally, we report that the flavonol modifies the transcription and/or activity of numerous transcription factors. In conclusion, our data support the idea that quercetin may actively accumulate in discrete cell structures and exert more than just antioxidant actions on epithelial cells by regulating mechanisms related to gene transcription.
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Affiliation(s)
- George Notas
- Laboratory of Experimental Endocrinology, University of Crete, School of Medicine, Heraklion, Greece
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15
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Hasskarl J, Kaufmann M, Schmid HA. Somatostatin receptors in non-neuroendocrine malignancies: the potential role of somatostatin analogs in solid tumors. Future Oncol 2011; 7:895-913. [PMID: 21732759 DOI: 10.2217/fon.11.66] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Somatostatin receptors (sstrs) are G-protein-coupled receptors that mediate various physiological effects when activated by the neuropeptide somatostatin or its synthetic analogs. In addition to the well-documented antisecretory effects of sstr2-preferential somatostatin analogs octreotide and lanreotide, ligand binding to sstr initiates an inhibitory action on tumor growth. This effect may result from both indirect actions (suppression of growth factors and growth-promoting hormones [e.g., GH/IGF-1 axis] and inhibition of angiogenesis) and direct actions (activation of antigrowth activities [e.g., apoptosis]). As solid tumor cells express multiple sstrs, there is a rationale to evaluate the potential antitumor effects of pasireotide (SOM230), a multireceptor-targeted somatostatin analog with high binding affinity for sstr1–3 and sstr5. Pasireotide reduces systemic IGF-1 levels more potently than currently available somatostatin analogs and has been well tolerated in clinical trials.
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Affiliation(s)
| | - Martina Kaufmann
- Novartis Pharma AG, Forum 1, Novartis Campus, CH-4056 Basel, Switzerland
| | - Herbert A Schmid
- Novartis Pharma AG, Forum 1, Novartis Campus, CH-4056 Basel, Switzerland
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Tsagarakis NJ, Drygiannakis I, Batistakis AG, Kolios G, Kouroumalis EA. Octreotide induces caspase activation and apoptosis in human hepatoma HepG2 cells. World J Gastroenterol 2011; 17:313-21. [PMID: 21253389 PMCID: PMC3022290 DOI: 10.3748/wjg.v17.i3.313] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2010] [Revised: 09/25/2010] [Accepted: 10/02/2010] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the role of octreotide on cellular proliferation and apoptosis of human hepatoma (HepG2) cells.
METHODS: We studied cellular proliferation, apoptosis and the possible internal caspase-mediated apoptosis pathway involved, after treatment of HepG2 carcinoma cells with octreotide in comparison with the apoptosis caused by tumor necrosis factor-α (TNF-α). Activities of caspase-3, caspase-9, caspase-8 and caspase-2 were studied, while apoptosis was investigated through detection of DNA fragmentation and through identification of apoptotic cells with the annexin-V/propidium iodide flow cytometric method.
RESULTS: After an initial increase in HepG2 cellular proliferation, a significant inhibition was observed with 10-8 mol/L octreotide, while TNF-α dose-dependently decreased proliferation. Early and late apoptosis was significantly increased with both substances. Octreotide significantly increased caspase-3, caspase-8 and caspase-2 activity. TNF-α significantly increased only caspase-2. Cellular proliferation was decreased after treatment with octreotide or TNF-α alone but, in contrast to TNF-α, octreotide decreased proliferation only at concentrations of 10-8 mol/L, while lower concentrations increased proliferation.
CONCLUSION: Our findings are suggestive of caspase-mediated signaling pathways of octreotide antitumor activity in HepG2 cells, and indicate that measurements of serum octreotide levels may be important, at least in clinical trials, to verify optimal therapeutic drug concentrations.
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A concentration-dependent effect of ursodeoxycholate on apoptosis and caspases activities of HepG2 hepatocellular carcinoma cells. Eur J Pharmacol 2010; 640:1-7. [DOI: 10.1016/j.ejphar.2010.04.023] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2009] [Revised: 03/28/2010] [Accepted: 04/20/2010] [Indexed: 01/19/2023]
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Borbath I, Leclercq IA, Sempoux C, Abarca-Quinones J, Desaeger C, Horsmans Y. Efficacy of lanreotide in preventing the occurrence of chemically induced hepatocellular carcinoma in rats. Chem Biol Interact 2010; 183:238-48. [DOI: 10.1016/j.cbi.2009.10.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2009] [Revised: 10/01/2009] [Accepted: 10/16/2009] [Indexed: 12/26/2022]
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Jia WD, Xu GL, Wang W, Wang ZH, Li JS, Ma JL, Ren WH, Ge YS, Yu JH, Liu WB. A somatostatin analogue, octreotide, inhibits the occurrence of second primary tumors and lung metastasis after resection of hepatocellular carcinoma in mice. TOHOKU J EXP MED 2009; 218:155-60. [PMID: 19478472 DOI: 10.1620/tjem.218.155] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Occurrence of second primary tumors and metastasis remains the major obstacles to prolonged survival of patients with primary hepatocellular carcinoma (HCC). A somatostatin analogue, octreotide, has been previously reported to inhibit the growth of human HCC xenografts in nude mice through its anti-angiogenic activity. It is therefore important to investigate whether octreotide could prevent second primary hepatomas or distant metastasis following resection of primary HCC. In this study, nude mice, bearing the human HCC xenografts with highly metastatic potential (LCI-D20) in the left liver lobe, underwent tumor resection, and received intraperitoneal administration of octreotide or saline as a control for 35 consecutive days. Compared with the control group, octreotide at the doses of 100 and 200 microg/kg/day significantly inhibited the growth (P < 0.001 and P < 0.001, respectively) and incidence of second primary tumors (P = 0.016 and P = 0.001, respectively), decreased lung metastasis (P < 0.001 and P < 0.001, respectively), and prolonged the life span (P = 0.029 and P = 0.006, respectively). Moreover, intratumoral angiogenesis quantified by microvessel density as well as serum and tissue vascular endothelial growth factor (VEGF) levels were considerably decreased in octreotide-treated animals compared to the control animals. These findings suggest that octreotide may prevent the occurrence of second primary hepatomas and lung metastasis after resection of primary HCC, which may be partially attributed to down-regulation of VEGF and subsequent reduction in tumor angiogenesis. Octreotide administration may be useful as an adjuvant therapy to improve survival of patients with HCC.
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Affiliation(s)
- Wei-Dong Jia
- Centre for the Study of Liver Cancer, Anhui Provincial Hospital, Anhui Medical University, Hefei, China
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Durán-Prado M, Gahete MD, Martínez-Fuentes AJ, Luque RM, Quintero A, Webb SM, Benito-López P, Leal A, Schulz S, Gracia-Navarro F, Malagón MM, Castaño JP. Identification and characterization of two novel truncated but functional isoforms of the somatostatin receptor subtype 5 differentially present in pituitary tumors. J Clin Endocrinol Metab 2009; 94:2634-43. [PMID: 19401364 DOI: 10.1210/jc.2008-2564] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
CONTEXT Somatostatin and its related peptide cortistatin exert multiple actions on normal and tumoral tissue targets through a family of receptors termed somatostatin receptor (sst)1-5. Despite the considerable advances in the knowledge on these receptors and their (patho)physiological roles, there is still evidence that additional receptors for these peptides should exist to fully explain their actions. OBJECTIVE The growing number of spliced variants found in similar receptor families, often present in tumors, and results from our group obtained on sst5 from other species (pig) led us to explore the existence of new human sst5 isoforms. DESIGN AND RESULTS A rapid amplification of cDNA ends PCR approach on samples from a human pituitary tumor and a cell line enabled identification of two novel alternatively spliced sst5 receptor variants. The sequences obtained encode putative proteins that correspond to truncated isoforms of five and four transmembrane domains (TMDs), accordingly named sst5TMD5 and sst5TMD4, respectively. Both novel receptors show a differential expression pattern in normal tissues and are also present in pituitary tumors of diverse etiology including nonfunctioning adenomas, corticotropinomas, somatotropinomas, and a prolactinoma. In contrast to the predominant plasma membrane localization of full-length sst5, both sst5TMD5 and sst5TMD4 show a preferentially intracellular localization. Despite their truncated nature, both receptors are functional, as shown by their ability to mediate selective, ligand-induced rises in free cytosolic calcium concentration. Specifically, whereas sst5TMD5 is selectivity activated by somatostatin compared with cortistatin, cells transfected with sst5TMD4 almost exclusively respond to cortistatin and not to somatostatin. CONCLUSIONS Our results demonstrate the existence of two previously unidentified sst5 spliced variants with distinct distribution in normal tissues and pituitary tumors, unique ligand-selective signaling properties, and subcellular distribution, which could contribute to somatostatin and cortistatin signaling in normal and tumoral cells.
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Affiliation(s)
- Mario Durán-Prado
- Department of Cell Biology, Physiology, and Immunology, University of Córdoba, and Centro de Investigación Biomédica en Red Fisiopatología de la Obesidad y Nutrición, E-14014 Córdoba Spain
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Samonakis DN, Notas G, Christodoulakis N, Kouroumalis EA. Mechanisms of action and resistance of somatostatin analogues for the treatment of hepatocellular carcinoma: a message not well taken. Dig Dis Sci 2008; 53:2359-65. [PMID: 18273705 DOI: 10.1007/s10620-007-0175-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2007] [Accepted: 12/20/2007] [Indexed: 02/08/2023]
Abstract
Somatostatin (SST) acts as an inhibitory peptide of various secretory and proliferative processes. Apart from neuroendocrine tumors, where SST analogues have an established role, they have been tested in other tumors such as hepatocellular carcinoma (HCC) in the view of the fact that chemotherapy is not working. Several positive reports have been published. Approximately 40% of patients respond with improved survival and an impressive quality of life. A usual misunderstanding in trial designs is that, although SST is not a rescue drug, selection of patients is inappropriate, with mostly moribund patients being recruited. SST analogues do not seem to work in 60% of HCCs and this has been linked to the presence of SST receptors (SSTR) in the tumor, while several resistance mechanisms might be involved. Future management should engage more specific SST analogues targeted to a tumor with a known SSTR map. The use of somatostatin analogues as an adjunct therapy in combination with other treatment modalities should also be investigated.
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Affiliation(s)
- Dimitrios N Samonakis
- Department of Gastroenterology & Hepatology, University Hospital of Heraklion, Heraklion, Crete, Greece.
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Volante M, Rosas R, Allìa E, Granata R, Baragli A, Muccioli G, Papotti M. Somatostatin, cortistatin and their receptors in tumours. Mol Cell Endocrinol 2008; 286:219-29. [PMID: 18248880 DOI: 10.1016/j.mce.2007.12.002] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2007] [Revised: 07/30/2007] [Accepted: 12/01/2007] [Indexed: 01/13/2023]
Abstract
Somatostatin (SS) and its synthetic analogs have a role in the treatment of neuroendocrine tumours both in terms of symptoms control and antiproliferative activities. These effects are mediated by five SS receptors, widely expressed in both human neuroendocrine and non-neuroendocrine tumours, which were demonstrated to be diagnostically and therapeutically valuable targets. Cortistatin (CST), a brain cortex peptide, partially homologous to SS and having similar functions is also expressed in peripheral tissues and tumours. CST binds all SS receptors, and, differently from SS, also the ghrelin receptor GHSR1a and the CST specific receptor MrgX2. The expression profile of CST is mostly restricted to neuroendocrine tumours (gastrointestinal, pancreas, lung, parathyroid, thyroid, adrenal). In these tumours, CST probably acts via the SS or ghrelin receptor, the MrgX2 receptor being absent. Thus, in comparison to SS analogs, CST synthetic analogs may represent additional diagnostic/therapeutic tools in those tumours expressing the receptors for SS, for ghrelin or for both peptides.
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Affiliation(s)
- M Volante
- Department of Clinical & Biological Sciences, University of Turin at San Luigi Hospital, Orbassano, University of Turin, Torino, Italy
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de Lecea L. Cortistatin--functions in the central nervous system. Mol Cell Endocrinol 2008; 286:88-95. [PMID: 18374474 DOI: 10.1016/j.mce.2007.12.014] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2007] [Revised: 11/29/2007] [Accepted: 12/19/2007] [Indexed: 11/22/2022]
Abstract
Cortistatin (CST) is a neuropeptide from the somatostatin (SRIF)/urotensin (UII) family named after its predominantly cortical expression and ability to depress cortical activity, which was discovered a decade ago. In vitro assays show CST is able to bind all five cloned somatostatin receptors and shares many pharmacological and functional properties with SRIF. However, distinct from SRIF, CST has been shown to induce slow-wave sleep, reduce locomotor activity, and activate cation selective currents not responsive to somatostatin. Different lines of evidence also indicate that CST, like SRIF, is involved in learning and memory processes. CST-14 may also function as an endogenous anti-convulsant. In addition to its role in cortical synchronization, CST-14 has emerged as an important mediator of immunity and inflammation. This review will cover some of the basic properties of CST in the brain, and will discuss new data on the role of CST in cortical activity.
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Affiliation(s)
- Luis de Lecea
- Department of Psychiatry and Behavioral Sciences, Stanford University, Palo Alto, CA 94304, USA.
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Bhandari S, Watson N, Long E, Sharpe S, Zhong W, Xu SZ, Atkin SL. Expression of somatostatin and somatostatin receptor subtypes 1-5 in human normal and diseased kidney. J Histochem Cytochem 2008; 56:733-43. [PMID: 18443363 DOI: 10.1369/jhc.2008.950998] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Somatostatin mediates inhibitory functions through five G protein-coupled somatostatin receptors (sst1-5). We used immunohistochemistry, immunofluorescence, and RT-PCR to determine the presence of somatostatin receptors sst1, sst2A, sst2B, sst3, sst4, and sst5 in normal and IgA nephropathy human kidney. All somatostatin receptors were detected in the thin tubules (distal convoluted tubules and loops of Henle) and thick tubules (proximal convoluted tubules) in the tissue sections from nephrectomy and biopsy samples. Immunopositive sst1 and sst4 staining was more condensed in the cytoplasm of tubular epithelial cells. In normal kidney tissue sections, podocytes and mesangial cells in the glomeruli stained for sst1, sst2B, sst4 and sst5, and stained weakly for sst3. In IgA kidney tissue, the expression of somatostatin receptors was significantly increased with particular immmunopositive staining for sst1, sst2B, sst4, and sst5 within glomeruli. In the epithelial cells, the staining for sst2B and sst4 in proximal tubules and sst1, sst2B, and sst5 in distal tubules was increased. The mRNA expression of sst1-5 was also detected by RT-PCR. Somatostatin and all five receptor subtypes were ubiquitously distributed in normal kidney and IgA nephropathy. The increased expression of somatostatin receptors in IgA nephropathy kidney might be the potential pathogenesis of inflammatory renal disease.
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Affiliation(s)
- Sunil Bhandari
- Department of Renal Medicine, Hull Royal Infirmary, Hull and East Yorkshire Hospitals NHS Trust, Kingston-upon Hull, UK.
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Therapy of experimental hepatic cancers with cytotoxic peptide analogs targeted to receptors for luteinizing hormone-releasing hormone, somatostatin or bombesin. Anticancer Drugs 2008; 19:349-58. [DOI: 10.1097/cad.0b013e3282f9adce] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Borbath I, Leclercq IA, Abarca-Quinones J, Desaeger C, Lebrun V, Moulin P, Sempoux C, Horsmans Y. Inhibition of early preneoplastic events in the rat liver by the somatostatin analog lanreotide. Cancer Sci 2007; 98:1831-9. [PMID: 17900309 PMCID: PMC11158449 DOI: 10.1111/j.1349-7006.2007.00626.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2007] [Revised: 08/16/2007] [Accepted: 08/21/2007] [Indexed: 12/21/2022] Open
Abstract
Hepatocellular carcinoma (HCC) is the third most common cause of cancer-related death, and its incidence is increasing worldwide. Due to the known risk factors (mainly hepatitis B and C viruses), we believe there is a rationale for a chemopreventive approach to treat HCC. Here, based on described in vitro data, we evaluated the preventive effects of lanreotide, a somatostatin analog, on the induction of early carcinogenic events. We monitored preneoplastic foci induced by a two-stage initiation/promotion model of hepatocarcinogenesis in male Wistar rats, using diethylnitrosamine and 2-acetylaminofluorene. Lanreotide was given starting the day after the first diethylnitrosamine injection. By quantitative morphometry, we showed that lanreotide significantly decreases the size of induced preneoplastic foci. Analysis of proliferation and apoptosis assessed by immunohistochemistry, showed decreased proliferation and increased cell death in rats treated with lanreotide. As these events were associated with a significant decreased expression of the cell cycle regulator cyclin D1 and an increased expression of the cyclin-dependent kinase inhibitor p27(kip1) compared to the non-treated group, it is tempting to speculate that these factors are involved in the favorable effect of lanreotide. In conclusion, lanreotide significantly decreases early carcinogenic transformation in a two-step rat model. As lanreotide has a low toxicity profile, we believe it would be interesting to evaluate its effect in chemoprevention of HCC.
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Affiliation(s)
- Ivan Borbath
- Gastroenterology Laboratory, Cliniques Universitaires Saint-Luc, Université catholique de Louvain, Avenue Hippocrate, 10, Brussels 1200, Belgium.
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Dimitroulopoulos D, Xinopoulos D, Tsamakidis K, Zisimopoulos A, Andriotis E, Panagiotakos D, Fotopoulou A, Chrysohoou C, Bazinis A, Daskalopoulou D, Paraskevas E. Long acting octreotide in the treatment of advanced hepatocellular cancer and overexpression of somatostatin receptors: randomized placebo-controlled trial. World J Gastroenterol 2007. [PMID: 17589893 DOI: 10.3748/wjg.v13.i13.3164] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM To estimate if and to what extent long acting octreotide (LAR) improves survival and quality of life in patients with advanced hepatocellular carcinoma (HCC). METHODS A total of 127 cirrhotics, stages A-B, due to chronic viral infections and with advanced HCC, were enrolled in the study. Scintigraphy with 111Indium labeled octreotide was performed in all cases. The patients with increased accumulation of radionuclear compound were randomized to receive either oral placebo only or octreotide/octreotide LAR only as follows: octreotide 0.5 mg s.c. every 8 h for 6 wk, at the end of wk 4-8 octreotide LAR 20 mg i.m. and at the end of wk 12 and every 4 wk octreotide LAR 30 mg i.m.. Follow-up was worked out monthly as well as the estimation of quality of life (QLQ-C30 questionnaire). Patients with negative somatostatin receptors (SSTR) detection were followed up in the same manner. RESULTS Scintigraphy demonstrated SSTR in 61 patients. Thirty were randomized to receive only placebo and 31 only octreotide. A significantly higher survival time was observed for the octreotide group (49+/-6 wk) as compared to the control group (28+/-1 wk) and to the SSTR negative group (28+/-2 wk), LR=20.39, df=2, P<0.01. The octreotide group presented 68.5% lower hazard ratio [95% CI (47.4%-81.2%)]. During the first year, a 22%, 39% and 43% decrease in the QLQ-C30 score was observed in each group, respectively. CONCLUSION The proposed therapeutic approach has shown to improve the survival and quality of life in SSTR positive patients with advanced HCC.
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Affiliation(s)
- D Dimitroulopoulos
- Liver Cancer Unit, Agios Savvas Cancer Hospital, 35 Parnassou str., GR-152 34 Halandri-Athens, and Laboratory of Biostatistics, Department of Nursing, University of Athens, Greece.
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Broglio F, Papotti M, Muccioli G, Ghigo E. Brain-gut communication: cortistatin, somatostatin and ghrelin. Trends Endocrinol Metab 2007; 18:246-51. [PMID: 17632010 DOI: 10.1016/j.tem.2007.06.004] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2007] [Revised: 05/29/2007] [Accepted: 06/20/2007] [Indexed: 12/11/2022]
Abstract
Although cortistatin (CST) shares great structural homology with somatostatin (SST) and binds to all SST receptor subtypes with similar affinity, these neurohormones have divergent biological roles, as evidenced by their different patterns of tissue expression and biological actions. Moreover, CST, but not SST, can bind to the proadrenomedullin N-terminal peptide (PAMP) receptor MrgX2 and type 1a growth hormone secretagogue (GHS) receptor (GHSR-1a), also known as the 'ghrelin' receptor. These findings suggest that CST-specific actions could be mediated by the GHSR-1a and CST might represent a link between the ghrelin and the SST systems. Here, we review the data leading to this working hypothesis and discuss the in vitro, in vivo and clinical implications of potential SST-receptor-independent, GHSR-1a-mediated neuroendocrine and metabolic effects of CST.
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Affiliation(s)
- Fabio Broglio
- Division of Endocrinology and Metabolism, Department of Internal Medicine, University of Turin, corso Dogliotti 14, 10126 Turin, Italy.
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Dimitroulopoulos D, Xinopoulos D, Tsamakidis K, Zisimopoulos A, Andriotis E, Panagiotakos D, Fotopoulou A, Chrysohoou C, Bazinis A, Daskalopoulou D, Paraskevas E. Long acting octreotide in the treatment of advanced hepatocellular cancer and overexpression of somatostatin receptors: Randomized placebo-controlled trial. World J Gastroenterol 2007; 13:3164-70. [PMID: 17589893 PMCID: PMC4436600 DOI: 10.3748/wjg.v13.i23.3164] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To estimate if and to what extent long acting octreotide (LAR) improves survival and quality of life in patients with advanced hepatocellular carcinoma (HCC).
METHODS: A total of 127 cirrhotics, stages A-B, due to chronic viral infections and with advanced HCC, were enrolled in the study. Scintigraphy with 111Indium labeled octreotide was performed in all cases. The patients with increased accumulation of radionuclear compound were randomized to receive either oral placebo only or octreotide/octreotide LAR only as follows: octreotide 0.5mg s.c. every 8 h for 6 wk, at the end of wk 4-8 octreotide LAR 20 mg i.m. and at the end of wk 12 and every 4 wk octreotide LAR 30mg i.m.. Follow-up was worked out monthly as well as the estimation of quality of life (QLQ-C30 questionnaire). Patients with negative somatostatin receptors (SSTR) detection were followed up in the same manner.
RESULTS: Scintigraphy demonstrated SSTR in 61 patients. Thirty were randomized to receive only placebo and 31 only octreotide. A significantly higher survival time was observed for the octreotide group (49 ± 6 wk) as compared to the control group (28 ± 1 wk) and to the SSTR negative group (28 ± 2 wk), LR = 20.39, df = 2, P < 0.01. The octreotide group presented 68.5% lower hazard ratio [95% CI (47.4%-81.2%)]. During the first year, a 22%, 39% and 43% decrease in the QLQ-C30 score was observed in each group respectively.
CONCLUSION: The proposed therapeutic approach has shown to improve the survival and quality of life in SSTR positive patients with advanced HCC.
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Affiliation(s)
- D Dimitroulopoulos
- Liver Cancer Unit, Agios Savvas Cancer Hospital, 35 Parnassou str., GR-152 34 Halandri-Athens, and Laboratory of Biostatistics, Department of Nursing, University of Athens, Greece.
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Xidakis C, Mastrodimou N, Notas G, Renieri E, Kolios G, Kouroumalis E, Thermos K. RT-PCR and immunocytochemistry studies support the presence of somatostatin, cortistatin and somatostatin receptor subtypes in rat Kupffer cells. ACTA ACUST UNITED AC 2007; 143:76-82. [PMID: 17481746 DOI: 10.1016/j.regpep.2007.03.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2006] [Revised: 03/14/2007] [Accepted: 03/18/2007] [Indexed: 01/31/2023]
Abstract
The present study investigated the presence of somatostatin receptor subtypes (ssts) and the endogenous peptides somatostatin and cortistatin in rat Kupffer cells, since modulation of these cells by somatostatin may be important for the beneficial effect of somatostatin analogues in a selected group of hepatocellular carcinoma patients. Kupffer cells were isolated from rat liver in agreement with national and EU guidelines. RT-PCR was employed to assess the expression of somatostatin, cortistatin and ssts in Kupffer cells. Western blot analysis and immunocytochemistry were employed to assess the expression and the localization of the receptors, respectively. Quiescent Kupffer cells were found to express sst(1-4) mRNA, while immunocytochemical studies supported the presence of only the sst(3) and sst(4) receptors, which were found to be internalized. However, sst1 and sst(2A) receptors were detected by western blotting. RT-PCR and RIA measurements support the presence of both somatostatin and cortistatin. Stimulation of the cells with LPS activated the expression of the sst(2), sst(3) and sst(4) receptors. The present data provide evidence to support the presence of ssts and the endogenous neuropeptides somatostatin and CST in rat Kupffer cells. Both peptides may act in an autocrine manner to regulate sst receptor distribution. Studies are in progress in order to further characterize the role of ssts in Kupffer cells and in hepatic therapeutics.
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Affiliation(s)
- C Xidakis
- Laboratory of Pharmacology, Department Basic Sciences, University of Crete, Faculty of Medicine, Heraklion, Crete, Greece
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31
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Notas G, Kampa M, Nifli AP, Xidakis K, Papasava D, Thermos K, Kouroumalis E, Castanas E. The inhibitory effect of opioids on HepG2 cells is mediated via interaction with somatostatin receptors. Eur J Pharmacol 2006; 555:1-7. [PMID: 17113072 DOI: 10.1016/j.ejphar.2006.10.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2006] [Revised: 09/29/2006] [Accepted: 10/05/2006] [Indexed: 11/30/2022]
Abstract
Opioids, acting via G-protein coupled membrane receptors, induce analgesia. However their role is not limited to their anti-nociceptive action. They are found in several peripheral tissues acting as negative regulators of cellular processes. Even though that is not fully elucidated, it becomes obvious that opioids exert their effects in close relation to other neuropeptides such as somatostatin. Hepatocellular carcinoma is one tumor, among others, which secrete bioactive peptides while somatostatin analogs exert an inhibitory effect. We have used the human hepatocyte-derived cancer cell line HepG2, in order to examine the effect of opioids on cell growth and their possible mode of action. Our results show that the opioid ethylketocyclazocine (EKC) inhibits cell proliferation and induces apoptosis. This inhibitory effect is not exerted via opioids receptors since it was not reversed by the opioid antagonist diprenorphine and functional opioid receptors were not found on HepG2 cells. On the contrary, we show that EKC binds to somatostatin receptors, and activates a PTP signalling cascade. In this respect, the interaction of opioids with somatostatin receptors on hepatocellular carcinoma cells, and the fact that they are widely used for pain control, may provide some additional clues for the discrepancies during treatment with somatostatin analogues.
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Affiliation(s)
- George Notas
- Laboratory of Gastroenterology and Hepatology, School of Medicine, University of Crete, Heraklion, Crete, Greece
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Samonakis DN, Christodoulakis N, Kouroumalis EA. Octreotide for unresectable hepatocellular carcinoma: beyond the first sight. J Clin Gastroenterol 2006; 40:86-7. [PMID: 16340641 DOI: 10.1097/01.mcg.0000190778.50279.26] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Lasfer M, Vadrot N, Schally AV, Nagy A, Halmos G, Pessayre D, Feldmann G, Reyl-Desmars FJ. Potent induction of apoptosis in human hepatoma cell lines by targeted cytotoxic somatostatin analogue AN-238. J Hepatol 2005; 42:230-7. [PMID: 15664249 DOI: 10.1016/j.jhep.2004.10.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2004] [Revised: 10/01/2004] [Accepted: 10/26/2004] [Indexed: 01/24/2023]
Abstract
BACKGROUND/AIMS The efficacy of a targeted cytotoxic hybrid somatostatin analogue AN-238 and of its superactive radical 2-pyrrolinodoxorubicin (AN-201) to induce apoptosis of HepG2 and Hep3B human hepatoma cell lines were studied. AN-238 was designed to selectively target tumor cells expressing somatostatin receptor subtypes (sst(s)). Its effects on HepG2 or Hep3B cells displaying or lacking tumor suppressor p53, respectively, were compared. Normal rat isolated hepatocytes were also tested. METHODS sst(s) were characterized by binding assays and RT-PCR. Cytotoxicity was quantified by flow cytometry. DNA fragmentation was studied by gel electrophoresis, PARP cleavage by Western blot and ROS formation using fluorescent probes. RESULTS Specific binding of iodinated RC-160 to HepG2 and Hep3B cells, and its displacement by AN-238 was characterized. mRNA for hsst(2A) was found in both cell lines. Flow cytometry showed a stronger effect of AN-238 than AN-201 to induce sub-G1 phase. DNA fragmentation, nuclear bodies, and PARP cleavage were observed. In addition, AN-238 increased formation of ROS more potently than AN-201. However, no inductions of DNA fragmentation by AN-201 or AN-238 were observed on rat hepatocytes. CONCLUSIONS Our results indicate that, in liver cancer, the cytotoxic somatostatin analogue AN-238 is a powerful agent that can induce apoptosis, through sst(s) and independently of p53.
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Affiliation(s)
- Malika Lasfer
- INSERM Unit 481, Faculté de Médecine Xavier Bichat, IFR 02, 16 rue Henri Huchard, BP 416, 75870 Paris Cedex 18, France
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Allia E, Tarabra E, Volante M, Cerrato M, Ghigo E, Muccioli G, Papotti M. Expression of cortistatin and MrgX2, a specific cortistatin receptor, in human neuroendocrine tissues and related tumours. J Pathol 2005; 207:336-45. [PMID: 16161007 DOI: 10.1002/path.1839] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Cortistatin (CST), a novel hormone originally described in the rat, mouse, and human cerebral cortex, displays structural and functional similarities to somatostatin (SRIF). CST binds to all five somatostatin receptors and, differently from SRIF, also binds to MrgX2, which has recently been identified as its specific receptor. Little is known about the distribution of CST and MrgX2 in peripheral non-tumour and neoplastic tissues. The aim of the present study was therefore to determine by immunohistochemistry and mRNA analysis (RT-PCR) the distribution of CST and MrgX2 in 56 human non-tumour and 108 tumour tissues, with special reference to neuroendocrine tissue types. Despite the high level of CST mRNA expression in non-tumour and tumour (both neuroendocrine and non-neuroendocrine) tissues, the presence of immunoreactive CST was confirmed in a subset of gastroenteropancreatic, parathyroid, and pituitary non-tumour cells only, and showed a predominantly focal pattern in most neuroendocrine tumours. Co-localization experiments in the gastroenteropancreatic system demonstrated that the normal CST-producing cells are delta cells, while in the adenohypophysis no preferential co-localization of CST with any of the pituitary hormones was observed. MrgX2 mRNA was variably detected in the hypothalamus, pituitary, thyroid, lung, gastroenteropancreatic tract, testis, and ovary, and was negative in the cerebral cortex, parathyroid, and adrenal, as well as in a variety of tumour types. Conversely, immunolocalization of MrgX2 protein was restricted to neurohypophysis and testis, whilst all tumours analysed were negative. A possible explanation for the discrepancy between RT-PCR and immunohistochemistry is that MrgX2 protein was widely detected in blood vessels, scattered lymphocytes, and gastrointestinal ganglia in both normal and neoplastic samples. The findings demonstrate a selective distribution of CST in normal and neoplastic neuroendocrine tissues, suggesting that CST might have a broader functional role than previously assumed, whereas possible autocrine/paracrine actions via its recently described specific receptor MrgX2 are restricted to selected tissues.
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Affiliation(s)
- Elena Allia
- Department of Biomedical Sciences and Oncology, University of Turin, Turin, Italy
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