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Gentilin E, Borges De Souza P, Ambrosio MR, Bondanelli M, Gagliardi I, Zatelli MC. Protein kinase C delta mediates Pasireotide effects in an ACTH-secreting pituitary tumor cell line. J Endocrinol Invest 2023; 46:2609-2616. [PMID: 37233978 PMCID: PMC10632222 DOI: 10.1007/s40618-023-02117-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 05/16/2023] [Indexed: 05/27/2023]
Abstract
PURPOSE Clinical control of corticotroph tumors is difficult to achieve since they usually persist or relapse after surgery. Pasireotide is approved to treat patients with Cushing's disease for whom surgical therapy is not an option. However, Pasireotide seems to be effective only in a sub-set of patients, highlighting the importance to find a response marker to this approach. Recent studies demonstrated that the delta isoform of protein kinase C (PRKCD) controls viability and cell cycle progression of an in vitro model of ACTH-secreting pituitary tumor, the AtT-20/D16v-F2 cells. This study aims at exploring the possible PRKCD role in mediating Pasireotide effects. METHODS It was assessed cell viability, POMC expression and ACTH secretion in AtT20/D16v-F2 cells over- or under-expressing PRKCD. RESULTS We found that Pasireotide significantly reduces AtT20/D16v-F2 cell viability, POMC expression and ACTH secretion. In addition, Pasireotide reduces miR-26a expression. PRKCD silencing decreases AtT20/D16v-F2 cell sensitivity to Pasireotide treatment; on the contrary, PRKCD overexpression increases the inhibitory effects of Pasireotide on cell viability and ACTH secretion. CONCLUSION Our results provide new insights into potential PRKCD contribution in Pasireotide mechanism of action and suggest that PRKCD might be a possible marker of therapeutic response in ACTH-secreting pituitary tumors.
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Affiliation(s)
- E Gentilin
- Bioacoustics Research Laboratory, Department of Neurosciences, University of Padua, Padua, Italy.
- Section of Endocrinology, Geriatrics & Internal Medicine, Dept. of Medical Sciences, University of Ferrara, Ferrara, Italy.
| | - P Borges De Souza
- Section of Endocrinology, Geriatrics & Internal Medicine, Dept. of Medical Sciences, University of Ferrara, Ferrara, Italy
| | - M R Ambrosio
- Section of Endocrinology, Geriatrics & Internal Medicine, Dept. of Medical Sciences, University of Ferrara, Ferrara, Italy
| | - M Bondanelli
- Section of Endocrinology, Geriatrics & Internal Medicine, Dept. of Medical Sciences, University of Ferrara, Ferrara, Italy
| | - I Gagliardi
- Section of Endocrinology, Geriatrics & Internal Medicine, Dept. of Medical Sciences, University of Ferrara, Ferrara, Italy
| | - M C Zatelli
- Section of Endocrinology, Geriatrics & Internal Medicine, Dept. of Medical Sciences, University of Ferrara, Ferrara, Italy.
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2
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von Selzam V, Theodoropoulou M. Innovative tumour targeting therapeutics in Cushing's disease. Best Pract Res Clin Endocrinol Metab 2022; 36:101701. [PMID: 36511278 DOI: 10.1016/j.beem.2022.101701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Cushing's disease (CD) is the most frequent form of endogenous hypercortisolism. Management of this devastating condition relies on pituitary surgery, while effective pharmacological treatment mainly focus on periphery targeting pharmaceuticals. Approved tumour-targeting drugs are limited to dopamine agonists and somatostatin analogues with frequently low efficacy and substantial side effects. Discoveries on the genetics and pathophysiology of corticotroph tumorigenesis brought forward new potential pharmacological targets. Compounds such as retinoic acid although promising in preclinical studies, are not as efficient in the clinic. Others, such as, silibinin, gefitinib and roscovitine are effective in preclinical models, but their efficacy and safety still needs to be determined in patients with CD.
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Affiliation(s)
- Vivian von Selzam
- Medizinische Klinik und Poliklinik IV, LMU Klinikum, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Marily Theodoropoulou
- Medizinische Klinik und Poliklinik IV, LMU Klinikum, Ludwig-Maximilians-Universität München, Munich, Germany.
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Albani A, Perez-Rivas LG, Tang S, Simon J, Lucia KE, Colón-Bolea P, Schopohl J, Roeber S, Buchfelder M, Rotermund R, Flitsch J, Thorsteinsdottir J, Herms J, Stalla G, Reincke M, Theodoropoulou M. Improved pasireotide response in USP8 mutant corticotroph tumours in vitro. Endocr Relat Cancer 2022; 29:503-511. [PMID: 35686696 DOI: 10.1530/erc-22-0088] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 06/10/2022] [Indexed: 12/13/2022]
Abstract
Cushing's disease is a rare but devastating and difficult to manage condition. The somatostatin analogue pasireotide is the only pituitary-targeting pharmaceutical approved for the treatment of Cushing's disease but is accompanied by varying efficacy and potentially severe side effects. Finding means to predict which patients are more likely to benefit from this treatment may improve their management. More than half of corticotroph tumours harbour mutations in the USP8 gene, and there is evidence of higher somatostatin receptor 5 (SSTR5) expression in the USP8-mutant tumours. Pasireotide has a high affinity for SSTR5, indicating that these tumours may be more sensitive to treatment. To test this hypothesis, we examined the inhibitory action of pasireotide on adrenocorticotrophic hormone synthesis in primary cultures of human corticotroph tumour with assessed USP8 mutational status and in immortalized murine corticotroph tumour cells overexpressing human USP8 mutants frequent in Cushing's disease. Our in vitro results demonstrate that pasireotide exerts a higher antisecretory response in USP8-mutant corticotroph tumours. Overexpressing USP8 mutants in a murine corticotroph tumour cell model increased endogenous somatostatin receptor 5 (Sstr5) transcription. The murine Sstr5 promoter has two binding sites for the activating protein 1 (AP-1) and USP8 mutants possibly to mediate their action by stimulating AP-1 transcriptional activity. Our data corroborate the USP8 mutational status as a potential marker of pasireotide response and describe a potential mechanism through which USP8 mutants may regulate SSTR5 gene expression.
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Affiliation(s)
- Adriana Albani
- Medizinische Klinik und Poliklinik IV, Ludwig-Maximilians-Universität München, Munich, Germany
| | | | - Sicheng Tang
- Medizinische Klinik und Poliklinik IV, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Julia Simon
- Medizinische Klinik und Poliklinik IV, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Kristin Elisabeth Lucia
- Medizinische Klinik und Poliklinik IV, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Paula Colón-Bolea
- Medizinische Klinik und Poliklinik IV, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Jochen Schopohl
- Medizinische Klinik und Poliklinik IV, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Sigrun Roeber
- Center for Neuropathology and Prion Research, LMU Munich, Munich, Germany
| | - Michael Buchfelder
- Department of Neurosurgery, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Roman Rotermund
- Department of Neurosurgery, Universitätskrankenhaus Hamburg-Eppendorf, Hamburg, Germany
| | - Jörg Flitsch
- Department of Neurosurgery, Universitätskrankenhaus Hamburg-Eppendorf, Hamburg, Germany
| | | | - Jochen Herms
- Center for Neuropathology and Prion Research, LMU Munich, Munich, Germany
| | - Günter Stalla
- Medizinische Klinik und Poliklinik IV, Ludwig-Maximilians-Universität München, Munich, Germany
- Medicover Neuroendocrinology, Munich, Germany
| | - Martin Reincke
- Medizinische Klinik und Poliklinik IV, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Marily Theodoropoulou
- Medizinische Klinik und Poliklinik IV, Ludwig-Maximilians-Universität München, Munich, Germany
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De Ravin E, Phan HAT, Harmsen S, Cho SS, Teng CW, Petersson EJ, White C, Galban EM, Hess R, Lee JYK. Somatostatin Receptor as a Molecular Imaging Target in Human and Canine Cushing Disease. World Neurosurg 2021; 149:94-102. [PMID: 33601082 DOI: 10.1016/j.wneu.2021.02.034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 02/07/2021] [Accepted: 02/08/2021] [Indexed: 11/25/2022]
Abstract
OBJECTIVES Fluorescence-guided surgery may improve completeness of resection in transsphenoidal surgery for Cushing disease (CD) by enabling visualization of residual tumor tissue at the margins. In this review we discuss somatostatin receptors (SSTRs) as targets for fluorescence-guided surgery and overview existing SSTR-specific imaging agents. We also compare SSTR expression in normal pituitary and corticotrophinoma tissues from human and canine CD patients to assess canines as a translational model for CD. METHODS A PubMed literature search was conducted for publications containing the terms canine, somatostatin receptor, Cushing's disease, and corticotroph adenoma. SSTR expression data from each study was documented as the presence or absence of expression or, when possible, the number of tumors expressing a given SSTR subtype within a group of tumors being studied. Studies that used reverse transcription polymerase chain reaction to quantify SSTR expression were selected for additional comparative analysis. RESULTS SSTR5 is strongly expressed in human corticotroph adenomas and weakly expressed in surrounding pituitary parenchyma, a pattern not conclusively observed in canine patients. SSTR2 mRNA expression is similar in human normal pituitary and corticotrophinoma cells but may be significantly higher in canine normal pituitary tissue than in corticotroph tumoral tissue. Limited data were available on SSTR subtypes 1, 3, and 4. CONCLUSIONS Further studies must fill the knowledge gaps related to species-specific SSTR expression, so using canine CD as a translational model may be premature. We do conclude that the expression profile of SSTR5 (i.e., high local expression in pituitary adenomas relative to normal surrounding tissues) makes SSTR5 a promising molecular target for FGS.
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Affiliation(s)
- Emma De Ravin
- Department of Neurosurgery at the Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, USA; Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Hoang Anh T Phan
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Stefan Harmsen
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Steve S Cho
- Department of Neurosurgery at the Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, USA; Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Clare W Teng
- Department of Neurosurgery at the Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, USA; Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - E James Petersson
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Caitlin White
- Department of Endocrinology at the Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Evelyn M Galban
- Department of Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Rebecka Hess
- Department of Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - John Y K Lee
- Department of Neurosurgery at the Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, USA.
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Sanders K, Galac S, Meij BP. Pituitary tumour types in dogs and cats. Vet J 2021; 270:105623. [PMID: 33641809 DOI: 10.1016/j.tvjl.2021.105623] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 01/18/2021] [Accepted: 01/19/2021] [Indexed: 12/25/2022]
Abstract
Pituitary tumours are common in dogs and are being increasingly recognized in cats. Pituitary tumours are usually classified as adenomas and should only be classified as carcinomas when there is evidence of metastatic spread of the tumour, which is rare. Despite the benign nature of most pituitary tumours, they can still compress or invade neighbouring tissues. Pituitary tumours can be functional (hormonally active) or non-functional (hormonally silent). The aim of this review was to provide an overview of the different pituitary tumour types in dogs and cats that have been reported in the literature. In dogs, the most common pituitary tumour type is the corticotroph adenoma, which can cause pituitary-dependent hypercortisolism. In cats, the most common pituitary tumour is the somatotroph adenoma, which can cause hypersomatotropism, and the second-most common is the corticotroph adenoma. A lactotroph adenoma has been described in one dog, while gonadotroph, thyrotroph and null cell adenomas have not been described in dogs or cats. Hormonally silent adenomas are likely underdiagnosed because they do not result in an endocrine syndrome. Tools used to classify pituitary tumours in humans, particularly immunohistochemistry for lineage-specific transcription factors, are likely to be useful to classify canine and feline pituitary tumours of unknown origin. Future studies are required to better understand the full range of pituitary adenoma pathology in dogs and cats and to determine whether certain adenoma subtypes behave more aggressively than others. Currently, the mechanisms that underlie pituitary tumorigenesis in dogs and cats are still largely unknown. A better understanding of the molecular background of these tumours could help to identify improved pituitary-targeted therapeutics.
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Affiliation(s)
- K Sanders
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 108, 3584 CM Utrecht, The Netherlands.
| | - S Galac
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 108, 3584 CM Utrecht, The Netherlands
| | - B P Meij
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 108, 3584 CM Utrecht, The Netherlands
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Albani A, Theodoropoulou M. Persistent Cushing's Disease after Transsphenoidal Surgery: Challenges and Solutions. Exp Clin Endocrinol Diabetes 2020; 129:208-215. [PMID: 32838436 DOI: 10.1055/a-1220-6056] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Transsphenoidal surgery remains the primary treatment for Cushing's disease (CD). However, despite the vast improvements in pituitary surgery, successful treatment of CD remains a great challenge. Although selective transsphenoidal removal of the pituitary tumor is a safe and effective procedure, the disease persists in around 22% of CD patients due to incomplete tumor resection. The persistence of hypercortisolism after pituitary surgery may also be the consequence of a misdiagnosis, as can occur in case of ectopic ACTH secretion or pseudo-Cushing. Considering the elevated mortality and morbidity characterizing the disease, a multidisciplinary approach is needed to minimize potential pitfalls occurring during the diagnosis, avoid surgical failure and provide the best care in those patients who have undergone unsuccessful surgery. In this review, we analyze the factors that could predict remission or persistence of CD after pituitary surgery and revise the therapeutic options in case of surgical failure.
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Affiliation(s)
- Adriana Albani
- Medizinische Klinik und Poliklinik IV, Klinikum der Universität München, Ludwig-Maximilians-Universität München, Munich, Germany
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Theodoropoulou M, Reincke M. Tumor-Directed Therapeutic Targets in Cushing Disease. J Clin Endocrinol Metab 2019; 104:925-933. [PMID: 30535260 DOI: 10.1210/jc.2018-02080] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 12/04/2018] [Indexed: 12/27/2022]
Abstract
CONTEXT The most frequent cause of endogenous hypercortisolism is Cushing disease (CD), a devastating condition associated with severe comorbidities and high mortality. Effective tumor-targeting therapeutics are limited. DESIGN Search in PubMed with key words "corticotroph" and "Cushing's disease" plus the name of the mentioned therapeutic agent and in associated references of the obtained papers. Additionally, potential therapeutics were obtained from ClinicalTrials.gov with a search for "Cushing disease." RESULTS At present, the tumor-targeted pharmacological therapy of CD is concentrated on dopamine agonists (cabergoline) and somatostatin analogs (pasireotide) with varying efficacy, escape from response, and considerable side effects. Preclinical studies on corticotroph pathophysiology have brought forward potential drugs such as retinoic acid, silibinin, and roscovitine, whose efficacy and safety remain to be determined. CONCLUSIONS For many patients with CD, effective tumor-targeted pharmacological therapy is still lacking. Coordinated efforts are pivotal in establishing efficacy and safety of novel therapeutics in this rare but devastating disease.
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Affiliation(s)
- Marily Theodoropoulou
- Medizinische Klinik und Poliklinik IV, Ludwig Maximilian University Munich, Munich, Germany
| | - Martin Reincke
- Medizinische Klinik und Poliklinik IV, Ludwig Maximilian University Munich, Munich, Germany
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8
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Gatto F, Arvigo M, Amarù J, Campana C, Cocchiara F, Graziani G, Bruzzone E, Giusti M, Boschetti M, Ferone D. Cell specific interaction of pasireotide: review of preclinical studies in somatotroph and corticotroph pituitary cells. Pituitary 2019; 22:89-99. [PMID: 30483918 DOI: 10.1007/s11102-018-0926-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND Pasireotide is a second-generation somatostatin (SRIF) receptor ligand (SRL), approved for medical treatment of acromegaly and Cushing's disease (CD). The molecule is a stable cyclohexapeptide synthetized based on SRIF structure. Differently from first-generation SRLs (e.g. octreotide), preferentially binding somatostatin receptor (SST) subtype 2 (SST2), pasireotide has high affinity for multiple SSTs (SST5 > SST2 > SST3 > SST1). Interestingly, early preclinical studies demonstrated that pasireotide shows distinct functional properties compared to SRIF and first-generation SRLs when binding SSTs. METHODS We aimed to highlight the differential receptor-targeted action of pasireotide in the treatment of somatotroph and corticotroph adenomas, throughout the critical revision of preclinical studies carried out on acromegaly and CD models. RESULTS Different authors demonstrated that the antisecretory effect of pasireotide in somatotroph adenoma cell cultures is comparable to that of the SST2-preferential agonist octreotide. Some reports even show a direct correlation between SST2 mRNA expression and GH reduction after pasireotide treatment, thus laying for a predominant role of SST2 in driving pasireotide efficacy in somatotropinomas in vitro. On the other hand, the inhibitory effect of pasireotide on ACTH secretion in corticotropinoma cells seems to be mainly mediated by SST5. Indeed, most reports show a higher potency and efficacy of pasireotide compared to SST2 preferential agonists, while functional studies confirm the pivotal role of SST5 targeting in corticotroph cells. CONCLUSIONS The analysis of preclinical studies carried out in somatotroph and corticoph adenomas points out that pasireotide shows a cell-specific activity, exerting its biological effects via different SSTs in the different adenoma histotypes.
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Affiliation(s)
- Federico Gatto
- Endocrinology Unit, Department of Internal Medicine, Policlinico San Martino, 16132, Genoa, Italy.
| | | | | | | | | | | | | | - Massimo Giusti
- Endocrinology Unit, Department of Internal Medicine, Policlinico San Martino, 16132, Genoa, Italy
- University of Genoa, Genoa, Italy
| | - Mara Boschetti
- Endocrinology Unit, Department of Internal Medicine, Policlinico San Martino, 16132, Genoa, Italy
- University of Genoa, Genoa, Italy
| | - Diego Ferone
- Endocrinology Unit, Department of Internal Medicine, Policlinico San Martino, 16132, Genoa, Italy
- University of Genoa, Genoa, Italy
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Sanders K, Kooistra HS, Galac S. Treating canine Cushing's syndrome: Current options and future prospects. Vet J 2018; 241:42-51. [PMID: 30340659 DOI: 10.1016/j.tvjl.2018.09.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 09/17/2018] [Accepted: 09/25/2018] [Indexed: 12/17/2022]
Abstract
Naturally occurring hypercortisolism, also known as Cushing's syndrome, is a common endocrine disorder in dogs that can be caused by an adenocorticotrophic hormone (ACTH)-producing pituitary adenoma (pituitary-dependent hypercortisolism, PDH; 80-85% of cases), or by an adrenocortical tumor (ACT; 15-20% of cases). To determine the optimal treatment strategy, differentiating between these two main causes is essential. Good treatment options are surgical removal of the causal tumor, i.e. hypophysectomy for PDH and adrenalectomy for an ACT, or radiotherapy in cases with PDH. Because these options are not without risks, not widely available and not suitable for every patient, pharmacotherapy is often used. In cases with PDH, the steroidogenesis inhibitor trilostane is most often used. In cases with an ACT, either trilostane or the adrenocorticolytic drug mitotane can be used. Although mostly effective, both treatments have disadvantages. This review discusses the current treatment options for canine hypercortisolism, and considers their mechanism of action, efficacy, adverse effects, and effect on survival. In addition, developments in both adrenal-targeting and pituitary-targeting drugs that have the potential to become future treatment options are discussed, as a more selective and preferably also tumor-targeted approach could have many advantages for both PDH and ACTs.
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Affiliation(s)
- K Sanders
- Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 108, 3584 CM Utrecht, The Netherlands
| | - H S Kooistra
- Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 108, 3584 CM Utrecht, The Netherlands
| | - S Galac
- Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 108, 3584 CM Utrecht, The Netherlands.
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Ribeiro-Oliveira A, Schweizer JROL, Amaral PHS, Bizzi MF, Silveira WCD, Espirito-Santo DTA, Zille G, Soares BS, Schmid HA, Yuen KCJ. Pasireotide treatment does not modify hyperglycemic and corticosterone acute restraint stress responses in rats. Stress 2018; 21:370-375. [PMID: 29661114 DOI: 10.1080/10253890.2018.1451838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
Abstract
Pasireotide is a new-generation somatostatin analog that acts through binding to multiple somatostatin receptor subtypes. Studies have shown that pasireotide induces hyperglycemia, reduces glucocorticoid secretion, alters neurotransmission, and potentially affects stress responses typically manifested as hyperglycemia and increased corticosterone secretion. This study specifically aimed to evaluate whether pasireotide treatment modifies glucose and costicosterone secretion in response to acute restraint stress. Male Holtzman rats of 150-200 g were treated with pasireotide (10 µg/kg/day) twice-daily for two weeks or vehicle for the same period. Blood samples were collected at baseline and after 5, 10, 30, and 60 min of restraint stress. The three experimental groups comprised of vehicle + restraint (VEHR), pasireotide + restraint (PASR), and pasireotide + saline (PASNR). Following pasireotide treatment, no significant differences in baseline glucose and corticosterone levels were observed among the three groups. During restraint, hyperglycemia was observed at 10 min (p < .01 for both comparisons), peaked at 30 min (p < .01 for both comparisons) and showed higher 60 min areas under glucose curves in the VEHR and PASR stressed groups when compared to the non-stressed PASNR group (p < .05 for both comparisons). Restraint also increased corticosterone secretion in the VEHR and PASR stressed groups at 5 min (p < .01 for both comparisons), and peaked at 30 min (p < .01 for both comparisons) with corresponding higher 60 min areas under corticosterone curves when compared to the non-stressed PASNR group (p < .01 for both comparisons). In conclusion, pasireotide treatment does not modify hyperglycemic- and corticosterone-restraint stress responses, thus preserving acute stress regulation.
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Affiliation(s)
- Antônio Ribeiro-Oliveira
- a Department of Internal Medicine, Laboratory of Endocrinology, School of Medicine , Federal University of Minas Gerais , Belo Horizonte , MG , Brazil
| | - Junia R O L Schweizer
- a Department of Internal Medicine, Laboratory of Endocrinology, School of Medicine , Federal University of Minas Gerais , Belo Horizonte , MG , Brazil
| | - Pedro H S Amaral
- a Department of Internal Medicine, Laboratory of Endocrinology, School of Medicine , Federal University of Minas Gerais , Belo Horizonte , MG , Brazil
| | - Mariana F Bizzi
- a Department of Internal Medicine, Laboratory of Endocrinology, School of Medicine , Federal University of Minas Gerais , Belo Horizonte , MG , Brazil
| | - Warley Cezar da Silveira
- a Department of Internal Medicine, Laboratory of Endocrinology, School of Medicine , Federal University of Minas Gerais , Belo Horizonte , MG , Brazil
| | - Daniel T A Espirito-Santo
- a Department of Internal Medicine, Laboratory of Endocrinology, School of Medicine , Federal University of Minas Gerais , Belo Horizonte , MG , Brazil
| | - Giancarlo Zille
- a Department of Internal Medicine, Laboratory of Endocrinology, School of Medicine , Federal University of Minas Gerais , Belo Horizonte , MG , Brazil
| | - Beatriz S Soares
- a Department of Internal Medicine, Laboratory of Endocrinology, School of Medicine , Federal University of Minas Gerais , Belo Horizonte , MG , Brazil
| | - Herbert A Schmid
- b Department of Oncology Research , Novartis Institutes for BioMedical Research, Novartis Pharma AG , Basel , Switzerland
| | - Kevin C J Yuen
- c Department of Neuroendocrinology , Barrow Pituitary Center, Barrow Neurological Institute , Phoenix , AZ, USA
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11
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Lottati M, Bruyette DS. Outcomes of the addition of pasireotide to traditional adrenal-directed treatment for dogs with pituitary-dependent hyperadrenocorticism secondary to macroadenoma: 9 cases (2013–2015). J Am Vet Med Assoc 2018; 252:1403-1408. [DOI: 10.2460/javma.252.11.1403] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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12
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Protein expression of somatostatin receptor 2, somatostatin receptor 5 and dopamine D2 receptor in normal pituitary gland and ACTH-secreting pituitary adenoma in dogs. Res Vet Sci 2018; 119:61-66. [PMID: 29864631 DOI: 10.1016/j.rvsc.2018.04.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 04/27/2018] [Accepted: 04/30/2018] [Indexed: 11/20/2022]
Abstract
PURPOSE To evaluate the protein expression of somatostatin receptor (SSTR) 2, SSTR5 and dopamine D2 receptor (DA2R)-targets of somatostatin analogs and dopamine agonists-in normal canine pituitary and canine adrenocorticotropic hormone (ACTH)-secreting pituitary adenomas. METHODS Six normal canine pituitary glands and 14 canine ACTH-secreting pituitary adenoma cases were included in this study. The protein expression of SSTR2, SSTR5 and DA2R was determined by double-label immunofluorescence staining of these receptors and ACTH. RESULTS SSTR2, SSTR5, and DA2R proteins were expressed in the anterior and intermediate lobes of normal canine pituitary glands. In the anterior pituitary lobes, the percentages of SSTR2-, SSTR5-, and DA2R-positive cells among the ACTH-positive population were 27.0 ± 8.6%, 27.9 ± 5.9%, and 34.0 ± 9.4%, respectively. In contrast, the corresponding percentages in the intermediate pituitary lobes were 97.8 ± 1.5%, 94.1 ± 4.4%, and 96.1 ± 6.6%, respectively. Of the 14 ACTH-secreting pituitary adenoma cases, 11, 12, and 6 cases expressed SSTR2, SSTR5, and DA2R, respectively. Additionally, four cases showed strong positive staining for both SSTR2 and SSTR5. Two of these were ACTH-secreting pituitary adenomas likely derived from the intermediate pituitary lobe, because these are α-Melanocyte-stimulation hormone (α-MSH)-positive stains. CONCLUSION Immunohistological detection and characterization of SSTR2, SSTR5 and DA2R may provide useful additional information for determining treatment options when an ACTH-secreting pituitary adenoma cannot be completely resected, or in the case of recurrence.
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Owen TJ, Martin LG, Chen AV. Transsphenoidal Surgery for Pituitary Tumors and Other Sellar Masses. Vet Clin North Am Small Anim Pract 2017; 48:129-151. [PMID: 29056398 DOI: 10.1016/j.cvsm.2017.08.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Transsphenoidal surgery is an option for dogs and cats with functional and nonfunctional pituitary masses or other sellar and parasellar masses. An adrenocorticotropic hormone-secreting tumor causing Cushing disease is the most common clinically relevant pituitary tumor in dogs, and the most common pituitary tumor seen in cats is a growth hormone-secreting tumor causing acromegaly. Transsphenoidal surgery can lead to rapid resolution of clinical signs and provide a cure for these patients. Because of the risks associated with this surgery, it should only be attempted by a cohesive pituitary surgery group with a sophisticated medical and surgical team.
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Affiliation(s)
- Tina J Owen
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, PO Box 647060, Pullman, WA 99164-7060, USA.
| | - Linda G Martin
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, PO Box 646610, Pullman, WA 99164-6610, USA
| | - Annie V Chen
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, PO Box 646610, Pullman, WA 99164-6610, USA
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Sato A, Ochi H, Harada Y, Yogo T, Kanno N, Hara Y. Bone morphogenetic protein 4 and bone morphogenetic protein receptor expression in the pituitary gland of adult dogs in healthy condition and with ACTH-secreting pituitary adenoma. Domest Anim Endocrinol 2017; 58:126-133. [PMID: 26542941 DOI: 10.1016/j.domaniend.2015.09.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Revised: 09/17/2015] [Accepted: 09/21/2015] [Indexed: 10/23/2022]
Abstract
The purpose of this study was to investigate the expression of bone morphogenetic protein 4 (BMP4) and its receptors, bone morphogenetic protein receptor I (BMPRI) and BMPRII, in the pituitary gland of healthy adult dogs and in those with ACTH-secreting pituitary adenoma. Quantitative polymerase chain reaction analysis showed that the BMP4 messenger RNA expression level in the ACTH-secreting pituitary adenoma samples was significantly lower than that in the normal pituitary gland samples (P = 0.03). However, there were no statistically significant differences between samples with respect to the messenger RNA expression levels of the receptors BMPRIA, BMPRIB, and BMPRII. Double-immunofluorescence analysis of the normal canine pituitary showed that BMP4 was localized in the thyrotroph (51.3 ± 7.3%) and not the corticotroph cells. By contrast, BMPRII was widely expressed in the thyrotroph (19.9 ± 5.2%) and somatotroph cells (94.7 ± 3.6%) but not in the corticotroph cells (P < 0.001, thyrotroph cells vs somatotroph cells). Similarly, in ACTH-secreting pituitary adenoma, BMP4 and BMPRII were not expressed in the corticotroph cells. Moreover, the percentage of BMP4-positive cells was also significantly reduced in the thyrotroph cells of the surrounding normal pituitary tissue obtained from the resected ACTH-secreting pituitary adenoma (8.3 ± 7.9%) compared with that in normal canine pituitary (P < 0.001). BMP4 has been reported to be expressed in corticotroph cells in the human pituitary gland. Therefore, the results of this study reveal a difference in the cellular pattern of BMP4-positive staining in the pituitary gland between humans and dogs and further revealed the pattern of BMPRII-positive staining in the dog pituitary gland. These species-specific differences regarding BMP4 should be considered when using dogs as an animal model for Cushing's disease.
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Affiliation(s)
- A Sato
- Division of Veterinary Surgery, Department of Veterinary Science, Faculty of Veterinary Medicine, Nippon Veterinary and Life Science University, Musashino-shi, Tokyo 180-8602, Japan
| | - H Ochi
- Department of Physiology and Cell Biology, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo 113-8510, Japan.
| | - Y Harada
- Division of Veterinary Surgery, Department of Veterinary Science, Faculty of Veterinary Medicine, Nippon Veterinary and Life Science University, Musashino-shi, Tokyo 180-8602, Japan
| | - T Yogo
- Division of Veterinary Surgery, Department of Veterinary Science, Faculty of Veterinary Medicine, Nippon Veterinary and Life Science University, Musashino-shi, Tokyo 180-8602, Japan
| | - N Kanno
- Division of Veterinary Surgery, Department of Veterinary Science, Faculty of Veterinary Medicine, Nippon Veterinary and Life Science University, Musashino-shi, Tokyo 180-8602, Japan
| | - Y Hara
- Division of Veterinary Surgery, Department of Veterinary Science, Faculty of Veterinary Medicine, Nippon Veterinary and Life Science University, Musashino-shi, Tokyo 180-8602, Japan
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Teshima T, Matsumoto H, Okusa T, Nakamura Y, Koyama H. Effects of Carbenoxolone on the Canine Pituitary-Adrenal Axis. PLoS One 2015; 10:e0135516. [PMID: 26262685 PMCID: PMC4532459 DOI: 10.1371/journal.pone.0135516] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Accepted: 06/13/2015] [Indexed: 11/25/2022] Open
Abstract
Cushing’s disease caused by pituitary corticotroph adenoma is a common endocrine disease in dogs. A characteristic biochemical feature of corticotroph adenomas is their relative resistance to suppressive negative feedback by glucocorticoids. The abnormal expression of 11beta-hydroxysteroid dehydrogenase (11HSD), which is a cortisol metabolic enzyme, is found in human and murine corticotroph adenomas. Our recent studies demonstrated that canine corticotroph adenomas also have abnormal expression of 11HSD. 11HSD has two isoforms in dogs, 11HSD type1 (HSD11B1), which converts cortisone into active cortisol, and 11HSD type2 (HSD11B2), which converts cortisol into inactive cortisone. It has been suggested that glucocorticoid resistance in corticotroph tumors is related to the overexpression of HSD11B2. Therefore it was our aim to investigate the effects of carbenoxolone (CBX), an 11HSD inhibitor, on the healthy dog’s pituitary-adrenal axis. Dogs were administered 50 mg/kg of CBX twice each day for 15 days. During CBX administration, no adverse effects were observed in any dogs. The plasma adrenocorticotropic hormone (ACTH), and serum cortisol and cortisone concentrations were significantly lower at day 7 and 15 following corticotropin releasing hormone stimulation. After completion of CBX administration, the HSD11B1 mRNA expression was higher, and HSD11B2 mRNA expression was significantly lower in the pituitaries. Moreover, proopiomelanocortin mRNA expression was lower, and the ratio of ACTH-positive cells in the anterior pituitary was also significantly lower after CBX treatment. In adrenal glands treated with CBX, HSD11B1 and HSD11B2 mRNA expression were both lower compared to normal canine adrenal glands. The results of this study suggested that CBX inhibits ACTH secretion from pituitary due to altered 11HSD expressions, and is potentially useful for the treatment of canine Cushing’s disease.
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Affiliation(s)
- Takahiro Teshima
- Division of Therapeutic Science I, Department of Veterinary Clinical Medicine, School of Veterinary Medicine, Faculty of Veterinary Science, Nippon Veterinary and Life Science University, 1-7-1 Kyonan-cho, Musashino-shi, Tokyo 180-8602, Japan
- * E-mail:
| | - Hirotaka Matsumoto
- Division of Therapeutic Science I, Department of Veterinary Clinical Medicine, School of Veterinary Medicine, Faculty of Veterinary Science, Nippon Veterinary and Life Science University, 1-7-1 Kyonan-cho, Musashino-shi, Tokyo 180-8602, Japan
| | - Tomoko Okusa
- Division of Therapeutic Science I, Department of Veterinary Clinical Medicine, School of Veterinary Medicine, Faculty of Veterinary Science, Nippon Veterinary and Life Science University, 1-7-1 Kyonan-cho, Musashino-shi, Tokyo 180-8602, Japan
| | - Yumi Nakamura
- Division of Therapeutic Science I, Department of Veterinary Clinical Medicine, School of Veterinary Medicine, Faculty of Veterinary Science, Nippon Veterinary and Life Science University, 1-7-1 Kyonan-cho, Musashino-shi, Tokyo 180-8602, Japan
| | - Hidekazu Koyama
- Division of Therapeutic Science I, Department of Veterinary Clinical Medicine, School of Veterinary Medicine, Faculty of Veterinary Science, Nippon Veterinary and Life Science University, 1-7-1 Kyonan-cho, Musashino-shi, Tokyo 180-8602, Japan
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Scudder CJ, Gostelow R, Forcada Y, Schmid HA, Church D, Niessen SJM. Pasireotide for the Medical Management of Feline Hypersomatotropism. J Vet Intern Med 2015; 29:1074-80. [PMID: 25945588 PMCID: PMC4895359 DOI: 10.1111/jvim.12608] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Revised: 03/23/2015] [Accepted: 04/07/2015] [Indexed: 12/22/2022] Open
Abstract
Background Feline hypersomatotropism (HST) is a cause of diabetes mellitus in cats. Pasireotide is a novel multireceptor ligand somatostatin analog that improves biochemical control of humans with HST. Hypothesis/Objectives Pasireotide improves biochemical control of HST and diabetes mellitus in cats. Animals Hypersomatotropism was diagnosed in diabetic cats with serum insulin‐like growth factor‐1 (IGF‐1) concentration >1,000 ng/mL by radioimmunoassay and pituitary enlargement. Methods Insulin‐like growth factor 1 was measured and glycemic control assessed using a 12‐hour blood glucose curve on days 1 and 5. On days 2, 3, and 4, cats received 0.03 mg/kg pasireotide SC q12h. IGF‐1, insulin dose, and estimated insulin sensitivity (product of the area under the blood glucose curve [BGC] and insulin dose) were compared pre‐ and post treatment. Paired t‐tests or Wilcoxon signed rank tests were employed for comparison where appropriate; a linear mixed model was created to compare BGC results. Results Insulin‐like growth factor 1 decreased in all 12 cats that completed the study (median [range] day 1: 2,000 ng/mL [1,051–2,000] and day 5: 1,105 ng/mL [380–1,727], P = .002, Wilcoxon signed rank test). Insulin dose was lower on day 5 than on day 1 (mean reduction 1.3 [0–2.7] units/kg/injection, P = .003, paired t‐test). The product of insulin dose and area under the BGC was lower on day 5 than day 1 (difference of means: 1,912; SD, 1523; u × mg/dL × hours, P = .001; paired t‐test). No clinically relevant adverse effects were encountered. Conclusions Short‐acting pasireotide rapidly decreased IGF‐1 in cats with HST and insulin‐dependent diabetes. The decrease in IGF‐1 was associated with increased insulin sensitivity.
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Affiliation(s)
- C J Scudder
- Department of Clinical Sciences and Services, Royal Veterinary College, North Mymms, UK
| | - R Gostelow
- Department of Clinical Sciences and Services, Royal Veterinary College, North Mymms, UK
| | - Y Forcada
- Department of Clinical Sciences and Services, Royal Veterinary College, North Mymms, UK
| | - H A Schmid
- Novartis Institutes for BioMedical Research, Oncology Research, Novartis Pharma AG, Basel, Switzerland
| | - D Church
- Department of Clinical Sciences and Services, Royal Veterinary College, North Mymms, UK
| | - S J M Niessen
- Department of Clinical Sciences and Services, Royal Veterinary College, North Mymms, UK.,Newcastle Medical School, Newcastle, Tyne and Wear, UK
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Murasawa S, Kageyama K, Sugiyama A, Ishigame N, Niioka K, Suda T, Daimon M. Inhibitory effects of SOM230 on adrenocorticotropic hormone production and corticotroph tumor cell proliferation in vitro and in vivo. Mol Cell Endocrinol 2014; 394:37-46. [PMID: 25011056 DOI: 10.1016/j.mce.2014.07.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 06/22/2014] [Accepted: 07/01/2014] [Indexed: 11/30/2022]
Abstract
Adrenocorticotropic hormone (ACTH) production by pituitary corticotroph adenomas is the main cause of Cushing's disease. A drug that targets pituitary ACTH-secreting adenomas would aid treatment of Cushing's disease. Octreotide, a somatostatin receptor type 2 (SSTR2)-preferring somatostatin analogue, has no effect on ACTH secretion in patients with Cushing's disease. The multiligand SOM230 (pasireotide) displays a much higher affinity for SSTR1 and SSTR5 than octreotide and suppresses ACTH secretion in cultures of human corticotroph tumors to a greater extent than octreotide. In the present in vitro and in vivo study, we determined the effect of SOM230 on ACTH production and cell proliferation of AtT-20 corticotroph tumor cells. SOM230 decreased proopiomelanocortin (POMC) mRNA levels in AtT-20 cells and ACTH levels in the culture medium of these cells, suggesting that SOM230 suppresses ACTH synthesis and secretion in corticotroph tumor cells. SOM230 also decreased cell proliferation and both cyclic adenosine monophosphate response element-binding protein and Akt phosphorylation in AtT-20 cells. SSTR5 knockdown inhibited the SOM230-induced decreases in cell proliferation. Fluorescence-activated cell sorting analyses revealed that SOM230 did not attenuate cell cycle progression. Tumor weight in mice xenografted with AtT-20 cells and treated with SOM230 was significantly lower than in AtT-20-xenografted control mice. SOM230 also significantly decreased plasma ACTH levels, and POMC and pituitary tumor transforming gene mRNA levels in the tumor cells. Thus, SOM230 inhibits ACTH production and corticotroph tumor cell proliferation in vitro and in vivo.
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Affiliation(s)
- Shingo Murasawa
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan
| | - Kazunori Kageyama
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan; Department of Endocrinology, Metabolism, and Infectious Diseases, Hirosaki University School of Medicine & Hospital, 53 Hon-cho, Hirosaki, Aomori 036-8563, Japan.
| | - Aya Sugiyama
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan
| | - Noriko Ishigame
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan
| | - Kanako Niioka
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan
| | - Toshihiro Suda
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan
| | - Makoto Daimon
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan
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Cuevas-Ramos D, Fleseriu M. Somatostatin receptor ligands and resistance to treatment in pituitary adenomas. J Mol Endocrinol 2014; 52:R223-40. [PMID: 24647046 DOI: 10.1530/jme-14-0011] [Citation(s) in RCA: 113] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Somatostatin (SST), an inhibitory polypeptide with two biologically active forms SST14 and SST28, inhibits GH, prolactin (PRL), TSH, and ACTH secretion in the anterior pituitary gland. SST also has an antiproliferative effect inducing cell cycle arrest and apoptosis. Such actions are mediated through five G-protein-coupled somatostatin receptors (SSTR): SSTR1-SSTR5. In GH-secreting adenomas, SSTR2 expression predominates, and somatostatin receptor ligands (SRLs; octreotide and lanreotide) directed to SSTR2 are presently the mainstays of medical therapy. However, about half of patients show incomplete biochemical remission, but the definition of resistance per se remains controversial. We summarize here the determinants of SRL resistance in acromegaly patients, including clinical, imaging features as well as molecular (mutations, SSTR variants, and polymorphisms), and histopathological (granulation pattern, and proteins and receptor expression) predictors. The role of SSTR5 may explain the partial responsiveness to SRLs in patients with adequate SSTR2 density in the cell membrane. In patients with ACTH-secreting pituitary adenomas, i.e. Cushing's disease (CD), SSTR5 is the most abundant receptor expressed and tumors show low SSTR2 density due to hypercortisolism-induced SSTR2 down-regulation. Clinical studies with pasireotide, a multireceptor-targeted SRL with increased SSTR5 activity, lead to approval of pasireotide for treatment of patients with CD. Other SRL delivery modes (oral octreotide), multireceptor-targeted SRL (somatoprim) or chimeric compounds targeting dopamine D2 receptors and SSTR2 (dopastatin), are briefly discussed.
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Affiliation(s)
- Daniel Cuevas-Ramos
- Department of MedicinePituitary Center, Cedars-Sinai Medical Center, Los Angeles, California, USANorthwest Pituitary Center and Departments of Medicine and Neurological SurgeryOregon Health and Science University, 3181 SW Sam Jackson Park Road (BTE 472), Portland, Oregon 97239, USA
| | - Maria Fleseriu
- Department of MedicinePituitary Center, Cedars-Sinai Medical Center, Los Angeles, California, USANorthwest Pituitary Center and Departments of Medicine and Neurological SurgeryOregon Health and Science University, 3181 SW Sam Jackson Park Road (BTE 472), Portland, Oregon 97239, USA
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Fleseriu M, Petersenn S. New avenues in the medical treatment of Cushing's disease: corticotroph tumor targeted therapy. J Neurooncol 2013; 114:1-11. [PMID: 23673515 PMCID: PMC3724972 DOI: 10.1007/s11060-013-1151-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Accepted: 05/06/2013] [Indexed: 01/23/2023]
Abstract
Cushing's disease (CD) is a condition of chronic hypercortisolism caused by an adrenocorticotropic hormone-secreting pituitary adenoma. First-line transsphenoidal surgery is not always curative and disease sometimes recurs. Radiotherapy often requires months or years to be effective, and is also not curative in many cases. Consequently, effective medical therapies for patients with CD are needed. Corticotroph adenomas frequently express both dopamine (D2) and somatostatin receptors (predominantly sstr5). Pasireotide, a somatostatin analog with high sstr5 binding affinity, has shown urinary free cortisol (UFC) reductions in most patients with CD in a large phase 3 trial, with UFC normalization and tumor shrinkage in a subset of patients. Adverse events were similar to other somatostatin analogs, with the exception of the degree and severity of hyperglycemia. Two small trials (one prospective and one retrospective) have suggested that cabergoline, a D2 receptor agonist, could be effective in normalizing UFC, but current long-term data results are conflicting. Combination treatment with pasireotide plus cabergoline and the adrenal steroidogenesis inhibitor ketoconazole has been successful, but further investigation in larger trials is necessary. Retinoic acid also showed interesting results in a recent very small prospective study. Glucocorticoid receptor blockade with mifepristone has recently demonstrated improvement in signs and symptoms of Cushing's and glycemic control; however, this modality does not address the etiology of the disease and has inherent adverse events related to its mechanism of action. Pituitary-targeted medical therapies will soon play a more prominent role in treating CD, and may potentially become first-line medical therapy when surgery fails or is contraindicated.
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Affiliation(s)
- Maria Fleseriu
- Departments of Medicine and Neurological Surgery, and Northwest Pituitary Center, Oregon Health & Science University, Portland, OR 97239, USA.
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Theodoropoulou M, Stalla GK. Somatostatin receptors: from signaling to clinical practice. Front Neuroendocrinol 2013; 34:228-52. [PMID: 23872332 DOI: 10.1016/j.yfrne.2013.07.005] [Citation(s) in RCA: 241] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 06/13/2013] [Accepted: 07/12/2013] [Indexed: 02/08/2023]
Abstract
Somatostatin is a peptide with a potent and broad antisecretory action, which makes it an invaluable drug target for the pharmacological management of pituitary adenomas and neuroendocrine tumors. Somatostatin receptors (SSTR1, 2A and B, 3, 4 and 5) belong to the G protein coupled receptor family and have a wide expression pattern in both normal tissues and solid tumors. Investigating the function of each SSTR in several tumor types has provided a wealth of information about the common but also distinct signaling cascades that suppress tumor cell proliferation, survival and angiogenesis. This provided the rationale for developing multireceptor-targeted somatostatin analogs and combination therapies with signaling-targeted agents such as inhibitors of the mammalian (or mechanistic) target of rapamycin (mTOR). The ability of SSTR to internalize and the development of rabiolabeled somatostatin analogs have improved the diagnosis and treatment of neuroendocrine tumors.
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Affiliation(s)
- Marily Theodoropoulou
- Department of Endocrinology, Max Planck Institute of Psychiatry, Kraepelinstrasse 10, 80804 Munich, Germany.
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[Neuroendocrinology in 2011]. ENDOCRINOLOGIA Y NUTRICION : ORGANO DE LA SOCIEDAD ESPANOLA DE ENDOCRINOLOGIA Y NUTRICION 2012; 59:311-25. [PMID: 22425316 DOI: 10.1016/j.endonu.2012.01.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2012] [Accepted: 01/25/2012] [Indexed: 01/04/2023]
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