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van der Pas R, Leebeek FWG, Hofland LJ, de Herder WW, Feelders RA. Hypercoagulability in Cushing's syndrome: prevalence, pathogenesis and treatment. Clin Endocrinol (Oxf) 2013; 78:481-8. [PMID: 23134530 DOI: 10.1111/cen.12094] [Citation(s) in RCA: 103] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2012] [Revised: 10/23/2012] [Accepted: 10/31/2012] [Indexed: 12/27/2022]
Abstract
Cushing's syndrome is not only accompanied by an increased prevalence of cardiovascular disease but also by a hypercoagulable state that is reflected by an increased incidence of venous thromboembolism. Overall, patients with CS have been reported to have a more than 10-fold increased risk of developing venous thromboembolism. Moreover, the incidence of postoperative thrombosis has been shown to be comparable to the risk after major orthopaedic surgery. Hypercoagulability in CS is due to both increased production of procoagulant factors with activation of the coagulation cascade and an impaired fibrinolytic capacity, resulting in a shortened activated partial thromboplastin time and an increased clot lysis time respectively. Although these abnormalities seem to improve 1 year following successful surgery, they do not yet normalize. Therefore, sustained biochemical remission might be required to fully resolve the hypercoagulable state in CS. Considering the risk of venous thromboembolism in uncontrolled CS there may be a rationale to give patients with active CS thromboprophylaxis. So far this seems warranted following surgical interventions. However, further studies are needed to determine the optimal dosage and duration of thromboprophylaxis.
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Varewijck AJ, Lamberts SWJ, Neggers SJCMM, Hofland LJ, Janssen JAMJL. IGF-I bioactivity might reflect different aspects of quality of life than total IGF-I in GH-deficient patients during GH treatment. J Clin Endocrinol Metab 2013; 98:761-8. [PMID: 23295465 DOI: 10.1210/jc.2012-2901] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
CONTEXT No relationship has been found between improvement in quality of life (QOL) and total IGF-I during GH therapy. AIM Our aim was to investigate the relationship between IGF-I bioactivity and QOL in GH-deficient (GHD) patients receiving GH for 12 months. METHODS Of 106 GHD patients, 84 on GH treatment discontinued therapy 4 weeks before establishing baseline values and 22 were GH-naive. IGF-I bioactivity was determined by IGF-I kinase receptor activation assay, total IGF-I by immunoassay (Immulite), and QOL by the disease-specific Question on Life Satisfaction Hypopituitarism (QLS-H) module and by the general SF-36 questionnaire (SF-36Q). RESULTS IGF-I bioactivity increased after 6 months (-2.5 vs -1.9 SD, P < .001) and did not further increase after 12 months (-1.8 SD, P = .23); total IGF-I increased from -2.3 to -0.9 SD (P < .001) and to -0.6 SD (P = .005), respectively. QLS-H did not change over 12 months (-0.66 ± 0.16 to -0.56 ± 0.17 SD [P = .42] to -0.68 ± 0.17 SD [P = .22]). The mental component summary of the SF-36Q increased from 47.4 (38.7-52.8) to 50.2 (43.1-55.3) (P = .001) and did not further improve (49.4 [42.1-54.1], P = .19); the physical component summary did not change (47.5 [42.0-54.2] vs 47.0 [41.9-55.3], P = .91, vs 48.3 [39.9-55.4], P = .66). After 12 months, IGF-I bioactivity was related to QLS-H (r = 0.28, P = .01); total IGF-I was not (r = 0.10, P = .37). IGF-I bioactivity and total IGF-I were related to PCS (r = 0.35, P = .001; and r = 0.31, P = .003). CONCLUSION IGF-I bioactivity remained subnormal after GH treatment and was positively related to QLS-H, whereas total IGF-I was not. This suggests that IGF-I bioactivity reflects different aspects of QOL than total IGF-I in GHD patients during GH treatment.
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Varewijck AJ, Boelen A, Lamberts SWJ, Fliers E, Hofland LJ, Wiersinga WM, Janssen JAMJL. Circulating IgGs may modulate IGF-I receptor stimulating activity in a subset of patients with Graves' ophthalmopathy. J Clin Endocrinol Metab 2013; 98:769-76. [PMID: 23295466 DOI: 10.1210/jc.2012-2270] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT There is a close association between levels of TSH binding inhibitory immunoglobulins (TBIIs) and Graves' ophthalmopathy (GO). In addition to the TSH receptor, the IGF-I receptor (IGF-IR) has been proposed to be a second autoantigen that plays a role in the pathogenesis of GO. OBJECTIVE The aim was to study relationships between TBII and serum IGF-IR stimulating activity in relationship to age in patients with GO. METHODS We performed a prospective study of 70 patients with GO (26 euthyroid, 39 subclinical hyperthyroid, 5 hyperthyroid; 8 males, 62 females; age, 47.9 ± 1.0 y). Patients were graded according to clinical activity score. IGF-IR stimulating activity was determined by IGF-IR kinase receptor activation assay; TBIIs were measured by immunoassay (Trak). Protein G magnetic beads were used to deplete serum of IgGs. RESULTS TBII and clinical activity score were positively related (r = 0.30; P = .01). In subjects with TBII above mean +1 SD, IGF-IR stimulating activity was positively related to age (r = 0.43; P = .05), whereas such a relationship was absent for subjects with TBII below the mean +1 SD (r = -0.04; P = .81). Depletion of IgGs from sera of patients with both TBII above the mean +1 SD and IGF-IR stimulating activity above the mean -1 SD decreased IGF-IR stimulating activity, whereas depletion in patients with TBII above the mean +1 SD but IGF-IR stimulating activity below the mean -1 SD did not change IGF-IR stimulating activity. CONCLUSIONS In subjects with TBII above the mean +1 SD, we observed an increase of IGF-IR stimulating activity with age. In a subgroup of these patients, depletion of IgGs significantly decreased IGF-IR stimulating activity, suggesting that, in a subset of patients with GO, IgGs may have IGF-IR stimulating activities.
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Abstract
CONTEXT Cushing's disease (CD) is associated with serious morbidity and, when suboptimally treated, an increased mortality. Although surgery is the first-line treatment modality for CD, hypercortisolism persists or recurs in an important subset of patients. Considering the deleterious effects of uncontrolled CD, there is a clear need for effective medical therapy. OBJECTIVE In this review, we discuss molecular targets for medical therapy, efficacy, and side effects of the currently used drugs to treat hypercortisolism and focus on recent developments resulting from translational and clinical studies. EVIDENCE ACQUISITION Selection of publications related to the study objective was performed via a PubMed search using relevant keywords and search terms. MAIN FINDINGS Medical therapy for CD can be classified into pituitary-directed, adrenal-blocking, and glucocorticoid receptor-antagonizing drugs. Recent studies demonstrate that somatostatin receptor subtype 5 (sst(5)) and dopamine receptor subtype 2 (D(2)) are frequently (co-)expressed by corticotroph adenomas. Pituitary-directed therapy with pasireotide and cabergoline, targeting sst(5) and D(2), respectively, is successful in approximately 25-30% of patients. Adrenal-blocking drugs can be effective by inhibiting steroidogenic enzyme activity. Finally, the glucocorticoid receptor antagonist mifepristone induces clinical and metabolic improvement in the majority of patients. Each drug can have important side effects that may impair long-term treatment. Generally, patients with moderate to severe hypercortisolism need combination therapy to normalize cortisol production. CONCLUSION Medical therapy for CD can be targeted at different levels and should be tailored in each individual patient. Future studies should examine the optimal dose and combination of medical treatment modalities for CD.
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Varewijck AJ, Brugts MP, Frystyk J, Goudzwaard JA, Uitterlinden P, Waaijers AM, Feng Y, Dimitrov DS, Lamberts SW, Hofland LJ, Janssen JA. Circulating insulin-like growth factors may contribute substantially to insulin receptor isoform A and insulin receptor isoform B signalling. Mol Cell Endocrinol 2013; 365:17-24. [PMID: 22982059 PMCID: PMC6959542 DOI: 10.1016/j.mce.2012.08.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Revised: 08/30/2012] [Accepted: 08/30/2012] [Indexed: 11/21/2022]
Abstract
BACKGROUND Only a fraction of circulating insulin-like activity is due to insulin itself. The aim of this study was to determine total serum insulin-like activity mediated via the insulin receptor isoform A (IR-A) and isoform B (IR-B) by using kinase receptor activation (KIRA) assays specific for the IR-A and IR-B. METHODS The IR-A and IR-B KIRA assays use human embryonic kidney cells which have been transfected with the human IR-A or IR-B gene and quantify serum-mediated phosphorylation of the IR. RESULTS Both IR KIRA assays were sensitive (detection limit 32 pmol/L) and precise (intra- and inter assay CV: <12% and <15%). The EC₅₀s of insulin, IGF-I and IGF-II were 1.4, 11.2 and 6.7 nmol/L for the IR-A KIRA assay, and 1.3, 31.0 and 15.7 nmol/L for the IR-B KIRA assay. The operational range of both assays allowed for determination of total insulin-like activity in human serum. Analysis of serum samples showed that there was a significant positive correlation between serum insulin-like and immunoreactive insulin concentrations (IR-A: r = 0.56, p = 0.01, IR-B: r = 0.68, p = 0.001). Importantly, addition of IGF-I or IGF-II antibodies to human serum samples could substantially decrease the endpoint signal in both KIRA assays. CONCLUSIONS We showed that serum IGF-I and IGF-II may substantially contribute to IR signalling. Since IR isoform specific KIRA assays also take into account the contribution of IGFs present in serum on IR signalling, they may help to gain more insight into the roles of IGF mediated IR-A and IR-B activation in health and disease.
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van Adrichem RCS, Hofland LJ, Feelders RA, De Martino MC, van Koetsveld PM, van Eijck CHJ, de Krijger RR, Sprij-Mooij DM, Janssen JAMJL, de Herder WW. Chromogranin A, Ki-67 index and IGF-related genes in patients with neuroendocrine tumors. Endocr Connect 2013; 2:172-7. [PMID: 24042314 PMCID: PMC3847918 DOI: 10.1530/ec-13-0052] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
UNLABELLED Chromogranin A (CgA) and the Ki-67 proliferation index are considered as important biochemical and pathological markers for clinical behaviour of gastroenteropancreatic neuroendocrine tumors (GEP NETs), respectively. The IGF system has been suggested as an important regulator of GEP NET proliferation and differentiation. A possible relationship between serum CgA (sCgA), Ki-67 proliferation index, and expression of IGF-related genes in patients with GEP NETs has not been demonstrated yet. This study investigates the relationship between sCgA, the Ki-67 proliferation index, and the expression of IGF-related genes in GEP NET tissues and their relation with 5-year survival. Tumor and blood samples from 22 GEP NET patients were studied. TUMORAL MRNA EXPRESSION OF IGF-RELATED GENES (IGFS IGF1, IGF2; IGF receptors: IGF1R, IGF2R; insulin receptors: subtype A (IR-A) and B (IR-B); IGF-binding proteins (IGFBPs): IGFBP1, IGFBP2, IGFBP3, and IGFBP6) was measured using quantitative RT-PCR. Ki-67 proliferation index was determined using immunohistochemistry. sCgA was measured with ELISA. Five-year survival in patients with nonelevated sCgA (n=11) was 91 vs 46% in patients with elevated sCgA (n=11) (P=0.006). IR-A mRNA expression was significantly higher in tumors obtained from patients with elevated sCgA than in those from patients with nonelevated sCgA (6.42±2.08 vs 2.60±0.40; P=0.04). This data suggests that sCgA correlates well with 5-year survival of GEP NET patients, and that IR-A mRNA expression correlates well with tumor mass in GEP NET patients.
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Gatto F, Feelders RA, van der Pas R, Kros JM, Waaijers M, Sprij-Mooij D, Neggers SJCMM, van der Lelij AJ, Minuto F, Lamberts SWJ, de Herder WW, Ferone D, Hofland LJ. Immunoreactivity score using an anti-sst2A receptor monoclonal antibody strongly predicts the biochemical response to adjuvant treatment with somatostatin analogs in acromegaly. J Clin Endocrinol Metab 2013; 98:E66-71. [PMID: 23118420 DOI: 10.1210/jc.2012-2609] [Citation(s) in RCA: 114] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Somatostatin receptor subtype 2 (sst2A) protein expression has been demonstrated to positively correlate with somatostatin analog treatment outcome in GH-secreting adenomas. Recently, a new rabbit monoclonal anti-sst2A antibody (clone UMB-1) has been validated as a reliable method to selectively detect sst2A protein levels in formalin-fixed tissues. OBJECTIVE The aim of the study was to establish whether the evaluation of sst2A protein levels, assessed with a routine reproducible immunohistochemistry protocol using UMB-1 antibody, may predict the successful adjuvant therapy with somatostatin analogs in acromegalic patients. DESIGN, SETTING, AND PATIENTS Thirty-six acromegalic patients from our referral hospital were evaluated retrospectively. Sst2A expression analysis was performed by immunohistochemistry in 25 patients and by quantitative RT-PCR in 26 patients. Sst2A immunoreactivity was evaluated using an immunoreactivity score (IRS), which takes into account both the percentage of positive cells and staining intensity. INTERVENTIONS Patients with persistent disease after surgery (n = 26) were treated with somatostatin analogs for a median duration of 6 months. MAIN OUTCOME MEASURE GH and IGF-I levels were measured before and after postoperative treatment. RESULTS Sst2A IRS showed a significant positive correlation with both GH (P = 0.039) and IGF-I (P = 0.001) suppression by octreotide. Sst2A IRS was negatively associated with IGF-I levels reached after treatment (P = 0.001), and patients that achieved IGF-I normalization showed significantly higher sst2A IRS compared to the group that was not normalized (P = 0.002). A sst2A IRS of at least 5 showed a sensitivity of 86% and a specificity of 91% in predicting IGF-I normalization during adjuvant octreotide treatment. CONCLUSION Sst2A IRS with the anti-sst2A antibody UMB-1 represents a valid tool in the clinical practice to identify acromegalic patients likely to be responders to adjuvant therapy with the currently available somatostatin analogs.
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Hofland J, de Herder WW, Derks L, Hofland LJ, van Koetsveld PM, de Krijger RR, van Nederveen FH, Horvath A, Stratakis CA, de Jong FH, Feelders RA. Regulation of steroidogenesis in a primary pigmented nodular adrenocortical disease-associated adenoma leading to virilization and subclinical Cushing's syndrome. Eur J Endocrinol 2013; 168:67-74. [PMID: 23065993 PMCID: PMC4100689 DOI: 10.1530/eje-12-0594] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
CONTEXT Primary pigmented nodular adrenocortical disease (PPNAD) can lead to steroid hormone overproduction. Mutations in the cAMP protein kinase A regulatory subunit type 1A (PRKAR1A) are causative of PPNAD. Steroidogenesis in PPNAD can be modified through a local glucocorticoid feed-forward loop. OBJECTIVE Investigation of regulation of steroidogenesis in a case of PPNAD with virilization. MATERIALS AND METHODS A 33-year-old woman presented with primary infertility due to hyperandrogenism. Elevated levels of testosterone and subclinical ACTH-independent Cushing's syndrome led to the discovery of an adrenal tumor, which was diagnosed as PPNAD. In vivo evaluation of aberrantly expressed hormone receptors showed no steroid response to known stimuli. Genetic analysis revealed a PRKAR1A protein-truncating Q28X mutation. After adrenalectomy, steroid levels normalized. Tumor cells were cultured and steroidogenic responses to ACTH and dexamethasone were measured and compared with those in normal adrenal and adrenocortical carcinoma cells. Expression levels of 17β-hydroxysteroid dehydrogenase (17β-HSD) types 3 and 5 and steroid receptors were quantified in PPNAD, normal adrenal, and adrenal adenoma tissues. RESULTS Isolated PPNAD cells, analogous to normal adrenal cells, showed both increased steroidogenic enzyme expression and steroid secretion in response to ACTH. Dexamethasone did not affect steroid production in the investigated types of adrenal cells. 17β-HSD type 5 was expressed at a higher level in the PPNAD-associated adenoma compared with control adrenal tissue. CONCLUSION PPNAD-associated adenomas can cause virilization and infertility by adrenal androgen overproduction. This may be due to steroidogenic control mechanisms that differ from those described for PPNAD without large adenomas.
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van der Pas R, de Herder WW, Hofland LJ, Feelders RA. New developments in the medical treatment of Cushing's syndrome. Endocr Relat Cancer 2012; 19:R205-23. [PMID: 22936543 DOI: 10.1530/erc-12-0191] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Cushing's syndrome (CS) is a severe endocrine disorder characterized by chronic cortisol excess due to an ACTH-secreting pituitary adenoma, ectopic ACTH production, or a cortisol-producing adrenal neoplasia. Regardless of the underlying cause, untreated CS is associated with considerable morbidity and mortality. Surgery is the primary therapy for all causes of CS, but surgical failure and ineligibility of the patient to undergo surgery necessitate alternative treatment modalities. The role of medical therapy in CS has been limited because of lack of efficacy or intolerability. In recent years, however, new targets for medical therapy have been identified, both at the level of the pituitary gland (e.g. somatostatin, dopamine, and epidermal growth factor receptors) and the adrenal gland (ectopically expressed receptors in ACTH-independent macronodular adrenal hyperplasia). In this review, results of preclinical and clinical studies with drugs that exert their action through these molecular targets, as well as already established medical treatment options, will be discussed.
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van der Pas R, Hofland LJ, Hofland J, Taylor AE, Arlt W, Steenbergen J, van Koetsveld PM, de Herder WW, de Jong FH, Feelders RA. Fluconazole inhibits human adrenocortical steroidogenesis in vitro. J Endocrinol 2012; 215:403-12. [PMID: 23038793 DOI: 10.1530/joe-12-0310] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The antifungal agent ketoconazole is often used to suppress cortisol production in patients with Cushing's syndrome (CS). However, ketoconazole has serious side effects and is hepatotoxic. Here, the in vitro effects of ketoconazole and fluconazole, which might be less toxic, on human adrenocortical steroidogenesis were compared. The effects on steroidogenesis were examined in primary cultures of nine human adrenocortical tissues and two human adrenocortical carcinoma cell lines. Moreover, the effects on mRNA expression levels of steroidogenic enzymes and cell growth were assessed. Ketoconazole significantly inhibited 11-deoxycortisol (H295R cells; maximum inhibition 99%; EC(50) 0.73 μM) and cortisol production (HAC15 cells; 81%; EC(50) 0.26 μM and primary cultures (mean EC(50) 0.75 μM)). In cultures of normal adrenal cells, ketoconazole increased pregnenolone, progesterone, and deoxycorticosterone levels, while concentrations of 17-hydroxypregnenolone, 17-hydroxyprogesterone, 11-deoxycortisol, DHEA, and androstenedione decreased. Fluconazole also inhibited 11-deoxycortisol production in H295R cells (47%; only at 1 mM) and cortisol production in HAC15 cells (maximum inhibition 55%; EC(50) 35 μM) and primary cultures (mean EC(50) 67.7 μM). In the cultures of normal adrenals, fluconazole suppressed corticosterone, 17-hydroxypregnenolone, and androstenedione levels, whereas concentrations of progesterone, deoxycorticosterone, and 11-deoxycortisol increased. Fluconazole (1 mM) slightly increased STAR mRNA expression in both cell lines. Neither compound affected mRNA levels of other steroidogenic enzymes or cell number. In conclusion, by inhibiting 11β-hydroxylase and 17-hydroxylase activity, pharmacological concentrations of fluconazole dose dependently inhibit cortisol production in human adrenocortical cells in vitro. Although fluconazole seems less potent than ketoconazole, it might become an alternative for ketoconazole to control hypercortisolism in CS. Furthermore, patients receiving fluconazole because of mycosis might be at risk for developing adrenocortical insufficiency.
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Virakul S, Dik WA, Hofland LJ, van Hagen PM, Dalm VASH. Macrophage-fibroblast interplay: a target for neuropeptide-based treatment of fibrotic disease? Lab Invest 2012. [PMCID: PMC3508890 DOI: 10.1186/1479-5876-10-s3-p22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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De Martino MC, van Koetsveld PM, Feelders RA, Sprij-Mooij D, Waaijers M, Lamberts SWJ, de Herder WW, Colao A, Pivonello R, Hofland LJ. The role of mTOR inhibitors in the inhibition of growth and cortisol secretion in human adrenocortical carcinoma cells. Endocr Relat Cancer 2012; 19:351-64. [PMID: 22420007 DOI: 10.1530/erc-11-0270] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Patients with adrenocortical carcinoma (ACC) need new treatment options. The aim of this study was to evaluate the effects of the mTOR inhibitors sirolimus and temsirolimus on human ACC cell growth and cortisol production. In H295, HAC15, and SW13 cells, we have evaluated mTOR, IGF2, and IGF1 receptor expressions; the effects of sirolimus and temsirolimus on cell growth; and the effects of sirolimus on apoptosis, cell cycle, and cortisol production. Moreover, the effects of sirolimus on basal and IGF2-stimulated H295 cell colony growth and on basal and IGF1-stimulated phospho-AKT, phospho-S6K1, and phospho-ERK in H295 and SW13 were studied. Finally, we have evaluated the effects of combination treatment of sirolimus with an IGF2-neutralizing antibody. We have found that H295 and HAC15 expressed IGF2 at a >1800-fold higher level than SW13. mTOR inhibitors suppressed cell growth in a dose-/time-dependent manner in all cell lines. SW13 were the most sensitive to these effects. Sirolimus inhibited H295 colony surviving fraction and size. These effects were not antagonized by IGF2, suggesting the involvement of other autocrine regulators of mTOR pathways. In H295, sirolimus activated escape pathways. The blocking of endogenously produced IGF2 increased the antiproliferative effects of sirolimus on H295. Cortisol production by H295 and HAC15 was inhibited by sirolimus. The current study demonstrates that mTOR inhibitors inhibit the proliferation and cortisol production in ACC cells. Different ACC cells have different sensitivity to the mTOR inhibitors. mTOR could be a target for the treatment of human ACCs, but variable responses might be expected. In selected cases of ACC, the combined targeting of mTOR and IGF2 could have greater effects than mTOR inhibitors alone.
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Ferone D, Pivonello R, Kwekkeboom DJ, Gatto F, Ameri P, Colao A, de Krijger RR, Minuto F, Lamberts SWJ, van Hagen PM, Hofland LJ. Immunohistochemical localization and quantitative expression of somatostatin receptors in normal human spleen and thymus: Implications for the in vivo visualization during somatostatin receptor scintigraphy. J Endocrinol Invest 2012; 35:528-34. [PMID: 21765239 DOI: 10.3275/7871] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND [111In-DTPA-D-Phe1]-octreotide scintigraphy allows the visualization of SRIF receptor (SSR)-expressing tumors, including thymic tumors, and normal tissues. While the spleen is clearly visualized, the thymus is not depicted, although both contain SSR. AIM We evaluated whether the heterogeneity, the type, and the amount of SSR might explain this contrasting finding. MATERIALS, METHODS, AND RESULTS By ligand-binding the number of [125I-Tyr11]-SRIF- 14 binding sites resulted comparable between the two tissues, whereas the number of [125I-Tyr3]-octreotide sites was significantly higher in the spleen (p<0.001). Quantitative RTPCR showed a significantly higher expression of sst2A mRNA in the spleen, whereas a significantly higher expression of SRIF and sst3 in the thymus. The highest density of sst2A in the spleen is in line with the in vivo uptake of [111In-DTPA-D-Phe1]- octreotide, which is considered a sst2-preferring ligand. The specificity is confirmed by the evidence that in vivo [111In-DTPA- D-Phe1]-octreotide uptake can be abolished during chronic administration of "cold" octreotide. Immunohistochemistry confirmed a preferential expression of sst2A on microenvironmental cells and of sst3 on lymphoid cells. CONCLUSIONS The heterogeneity of SSR expression and the higher SRIF content explain the lack of thymus visualization during scintigraphy, whereas thymic tumors, which do not express SRIF, are visualized. Apart from the affinity of the radioligand, also the efficacy of the internalization is crucial for the in vivo uptake, and both heterogeneity and SRIF content affect this process. These observations might have an important impact when interpretating in vivo visualization of SSR-positive lesions, and when treatment with novel SRIF analogs is considered.
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Hofland J, Delhanty PJ, Steenbergen J, Hofland LJ, van Koetsveld PM, van Nederveen FH, de Herder WW, Feelders RA, de Jong FH. Melanocortin 2 receptor-associated protein (MRAP) and MRAP2 in human adrenocortical tissues: regulation of expression and association with ACTH responsiveness. J Clin Endocrinol Metab 2012; 97:E747-54. [PMID: 22419722 DOI: 10.1210/jc.2011-2328] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT ACTH stimulates adrenocortical steroid production through the melanocortin 2 receptor (MC2R). MC2R trafficking and signaling are dependent on the MC2R accessory protein (MRAP). The MRAP homolog MRAP2 also transports the MC2R to the cell surface but might prevent activation. OBJECTIVE The objective of the investigation was to study the regulatory pathways of MRAP and MRAP2 and their contributions to ACTH responsiveness in human adrenal tissues. DESIGN AND SETTING MRAP, MRAP2, and MC2R expression levels were studied in 32 human adrenocortical samples. Regulation of these mRNAs was investigated in 43 primary adrenal cultures, stimulated with ACTH, forskolin, angiotensin II (AngII), phorbol-12-myristate-13-acetate (PMA), or dexamethasone. The induction of cortisol, cAMP, and ACTH-responsive genes after treatment with ACTH was related to MRAP, MRAP2, and MC2R expression levels. RESULTS MRAP and MRAP2 levels were lower in adrenocortical carcinomas (ACC) than in other adrenal tissues (P < 0.001). Patient ACTH and cortisol levels were associated with adrenal levels of MRAP and MC2R in adrenal hyperplasia samples (P < 0.05) but not in tumors. ACTH induced the expression of MRAP 11 ± 2.1-fold and MC2R 20 ± 3.8-fold in all adrenal tissue types (mean ± SEM, both P < 0.0001), whereas AngII augmented these mRNAs 4.0 ± 1.2-fold and 12.6 ± 3.2-fold (P < 0.0001) in all but the ACC. MRAP2 expression was suppressed by forskolin (-24 ± 15%, P = 0.013) and PMA (-22 ± 7%, P = 0.0007). MRAP, MRAP2, or MC2R levels were not associated with the induction of cortisol, cAMP, or gene expression by ACTH in vitro. CONCLUSION MRAP and MC2R expression is induced by ACTH and AngII, which would facilitate cell surface receptor availability. Physiological expression levels of MRAP, MRAP2, and MC2R were not limiting for ACTH sensitivity.
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van der Pas R, de Bruin C, Leebeek FWG, de Maat MPM, Rijken DC, Pereira AM, Romijn JA, Netea-Maier RT, Hermus AR, Zelissen PMJ, de Jong FH, van der Lely AJ, de Herder WW, Lamberts SWJ, Hofland LJ, Feelders RA. The hypercoagulable state in Cushing's disease is associated with increased levels of procoagulant factors and impaired fibrinolysis, but is not reversible after short-term biochemical remission induced by medical therapy. J Clin Endocrinol Metab 2012; 97:1303-10. [PMID: 22278425 DOI: 10.1210/jc.2011-2753] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
CONTEXT Cushing's disease (CD) is accompanied by an increased risk of venous thromboembolism. Surgery is the primary treatment of CD. OBJECTIVE The aim of the study was to compare hemostatic parameters between patients with CD and controls and to evaluate the effect of medical treatment of CD on hemostasis. DESIGN AND SETTING During 80 d, stepwise medical treatment was applied with the somatostatin analog pasireotide, the dopamine agonist cabergoline, and ketoconazole, which suppresses adrenocortical steroidogenesis, at four university medical centers in The Netherlands. PATIENTS Seventeen patients with de novo, residual, or recurrent CD were included. MAIN OUTCOME MEASURES We measured urinary free cortisol and parameters of coagulation and fibrinolysis. RESULTS Patients with CD had significantly higher body mass index (P < 0.001), shortened activated partial thromboplastin time (P < 0.01), and higher levels of fibrinogen, Factor VIII, and protein S activity (P < 0.05) compared to healthy control subjects. In addition, fibrinolytic capacity was impaired in patients with CD as reflected by prolonged clot lysis time (P < 0.001) and higher levels of plasminogen activator inhibitor type 1, thrombin-activatable fibrinolysis inhibitor, and α2-antiplasmin (P < 0.01). There were no statistically significant differences in von Willebrand factor:antigen, antithrombin, and protein C activity. After 80 d, 15 of 17 patients had normalized urinary free cortisol excretion. Despite biochemical remission, only slight decreases in antithrombin (P < 0.01) and thrombin-activatable fibrinolysis inhibitor (P < 0.05) levels were observed. Other parameters of coagulation and fibrinolysis did not change significantly. CONCLUSIONS The hypercoagulable state in patients with CD, which is explained by both increased production of procoagulant factors and impaired fibrinolysis, is not reversible upon short-term biochemical remission after successful medical therapy. This may have implications for the duration of anticoagulant prophylaxis in patients with (cured) CD.
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Gatto F, Barbieri F, Gatti M, Wurth R, Schulz S, Ravetti JL, Zona G, Culler MD, Saveanu A, Giusti M, Minuto F, Hofland LJ, Ferone D, Florio T. Balance between somatostatin and D2 receptor expression drives TSH-secreting adenoma response to somatostatin analogues and dopastatins. Clin Endocrinol (Oxf) 2012; 76:407-14. [PMID: 21848909 DOI: 10.1111/j.1365-2265.2011.04200.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
CONTEXT First-line therapy for thyrotropin-secreting pituitary adenomas (TSHomas) is neurosurgery, while medical treatment rests mainly on somatostatin analogues. Clinically available sst(2) -preferring analogues, octreotide and lanreotide, induce normalization of hormone levels in approximately 90% of patients and tumour shrinkage in 45%. OBJECTIVE We evaluated somatostatin 1, 2, 3 and 5 and dopamine D2 receptor expression in tumour samples from three TSHomas, and the relationships between receptor expression, in vitro antiproliferative response and clinical data, including octreotide test and three months of therapy with octreotide long-acting repeatable (LAR). TSHoma cell proliferation was tested in vitro using octreotide, cabergoline and two chimeric compounds, BIM-23A760 and BIM-23A387. RESULTS All patients showed significant TSH lowering to acute octreotide test, but a hormonal response to long-term treatment was observed in only two patients, showing a high sst(5) /sst(2) ratio. Patient 2, characterized by high expression of sst(2) and sst(1) and a relative lower expression of sst(5) , experienced tachyphylaxis after prolonged octreotide treatment. In vitro, the somatostatin/dopamine receptor agonist BIM-23A760 caused the highest antiproliferative effect among those tested. Combined treatment with octreotide and cabergoline displayed an additive effect of magnitude comparable to that of the other chimeric compound (BIM-23A387). Octreotide resistance was confirmed in cells isolated from the nonresponder patient, although it could be overcome by treatment with the chimeric compounds. CONCLUSIONS A high sst(5) /sst(2) ratio might be predictive of a positive outcome to long-term treatment with somatostatin analogues in TSHomas. Moreover, combined somatostatin and D(2) receptor targeting might be considered as a potential tool to improve the response rate in octreotide-resistant tumours.
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de Bruin C, Hofland LJ, Nieman LK, van Koetsveld PM, Waaijers AM, Sprij-Mooij DM, van Essen M, Lamberts SWJ, de Herder WW, Feelders RA. Mifepristone effects on tumor somatostatin receptor expression in two patients with Cushing's syndrome due to ectopic adrenocorticotropin secretion. J Clin Endocrinol Metab 2012; 97:455-62. [PMID: 22090282 PMCID: PMC3275368 DOI: 10.1210/jc.2011-1264] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Two patients presented with Cushing's syndrome due to ectopic ACTH secretion. Initial localization studies included computed tomography, magnetic resonance imaging, and octreoscans ((111)In-pentreotide scintigraphy), which were negative in both patients. They were treated with the glucocorticoid receptor antagonist mifepristone, with improvement in their clinical symptoms. Follow-up octreoscans after, respectively, 6 and 12 months showed the unequivocal presence of a bronchial carcinoid in both patients. OBJECTIVE The objective of the study was to correlate in vivo and in vitro findings in patients with ectopic ACTH-producing syndrome. METHODS We determined the expression of somatostatin and dopamine receptors by immunohistochemistry (patients 1 and 2), quantitative PCR, and in vitro culturing of tumor cells (patient 1 only). IN VITRO RESULTS: Both tumors were strongly positive for somatostatin receptor type 2 (sst(2)) on immunohistochemistry, whereas one of the tumors (patient 1) was also dopamine receptor subtype 2 (D(2)) positive on both immunohistochemistry and quantitative PCR. Octreotide (a sst(2) preferring analog) and cabergoline (D(2) agonist) both decreased the ACTH levels in the cultured tumor cells of patient 1. CONCLUSION We describe two patients with ACTH-producing bronchial carcinoids, in whom a direct down-regulatory effect of glucocorticoid levels on tumoral sst(2) receptor expression is suggested by a remarkable change in octreoscan status after successful mifepristone therapy. Further studies will have to demonstrate whether glucocorticoid lowering or antagonizing therapy may be used to improve the diagnostic accuracy of somatostatin receptor scintigraphy in patients with ectopic ACTH production of unknown primary origin.
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Vitale G, Zappavigna S, Marra M, Dicitore A, Meschini S, Condello M, Arancia G, Castiglioni S, Maroni P, Bendinelli P, Piccoletti R, van Koetsveld PM, Cavagnini F, Budillon A, Abbruzzese A, Hofland LJ, Caraglia M. The PPAR-γ agonist troglitazone antagonizes survival pathways induced by STAT-3 in recombinant interferon-β treated pancreatic cancer cells. Biotechnol Adv 2012; 30:169-84. [DOI: 10.1016/j.biotechadv.2011.08.001] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2011] [Revised: 07/22/2011] [Accepted: 08/02/2011] [Indexed: 12/30/2022]
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Abstract
Somatostatin (SS) and dopamine (DA) receptors have been highlighted as two critical regulators in the negative control of hormonal secretion in a wide group of human endocrine tumors. Both families of receptors belong to the superfamily of G protein-coupled receptors and share a number of structural and functional characteristics. Because of the generally reported high expression of somatostatin receptors (SSTRs) in neuroendocrine tumors (NET), somatostatin analogs (SSA) have a pronounced role in the medical therapy for this class of tumors, especially pituitary adenomas and well-differentiated gastroenteropancreatic NET (GEP NET). Moreover, NET express not only SSTR but also frequently dopamine receptors (DRs), and DA agonists targeting the D(2) receptor (D(2)) have been demonstrated to be effective in controlling hormone secretion and cell proliferation in in vivo and in vitro studies. The treatment with SSAs combined with DA agonists has already been demonstrated efficacious in a subgroup of patients with GH-secreting pituitary adenomas and few reported cases of carcinoids. The recent availability of new selective and universal SSA and DA agonists, as well as the chimeric SS/DA compounds, may shed new light on the potential role of SSTR and D(2) as combined targets for biotherapy in NET. This review provides an overview of the latest studies evaluating the expression of SSTR and DR in NET, focusing on their co-expression and the possible clinical implications of such co-expression. Moreover, the most recent insights in SSTR and D(2) pathophysiology and the future perspectives for treatment with SSA, DA agonists, and SS/DA chimeric compounds are discussed.
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Morak MJ, van Koetsveld PM, Kanaar R, Hofland LJ, van Eijck CH. Type I interferons as radiosensitisers for pancreatic cancer. Eur J Cancer 2011; 47:1938-45. [DOI: 10.1016/j.ejca.2011.03.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2010] [Accepted: 03/08/2011] [Indexed: 01/02/2023]
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Varewijck AJ, Lamberts SWJ, Uitterlinden P, Hofland LJ, Janssen JAMJL. IGF-I bioactivity better reflects growth hormone deficiency than total IGF-I. J Clin Endocrinol Metab 2011; 96:2248-54. [PMID: 21565786 DOI: 10.1210/jc.2011-0051] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT GH is considered the main regulator of circulating IGF-I. Total (extractable) IGF-I is therefore routinely used for diagnosis of GH deficiency (GHD) and for monitoring treatment. Methods currently used for measurement of circulating total IGF-I may be hampered by interferences of IGF-binding proteins. Recently a kinase receptor activation assay was developed to determine IGF-I bioactivity in human serum. The principle of this assay is based on quantification of IGF-I receptor activation after stimulation with serum in vitro. OBJECTIVE The objective of the study was to investigate the diagnostic potential of IGF-I bioactivity in adults with GHD. DESIGN This was a single-center observational study. STUDY PARTICIPANTS Ninety-four GH-untreated patients diagnosed with GHD by GH-provocative tests were included. MAIN OUTCOME MEASURES IGF-I bioactivity (determined by the IGF-I kinase receptor activation assay) and total IGF-I (determined by immunoassay) were measured in fasting blood samples. RESULTS IGF-I bioactivity was more frequently below the normal range (<-2 sd) in untreated GH-deficient patients than total IGF-I levels (81.9 vs. 61.7%, respectively), especially in patients older than 40 years of age. IGF-I bioactivity decreased with the duration of GHD, whereas total IGF-I did not. With a decreasing number of additional pituitary deficits, total IGF-I levels more frequently remained within the normal range, whereas the percentage below the normal range was high for IGF-I bioactivity, independent of additional deficits. CONCLUSION Determination of IGF-I bioactivity may offer advantages in the evaluation of adult GHD compared with total IGF-I as bioactivity better reflects GHD as defined by GH stimulation tests, especially in subjects older than 40 years of age.
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Erdmann J, Vitale G, van Koetsveld PM, Croze E, Sprij-Mooij DM, Hofland LJ, van Eijck CH. Effects of Interferons α/β on the Proliferation of Human Micro- and Macrovascular Endothelial Cells. J Interferon Cytokine Res 2011; 31:451-8. [DOI: 10.1089/jir.2009.0103] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
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Al-Azzawi H, Yacqub-Usman K, Richardson A, Hofland LJ, Clayton RN, Farrell WE. Reversal of endogenous dopamine receptor silencing in pituitary cells augments receptor-mediated apoptosis. Endocrinology 2011; 152:364-73. [PMID: 21177832 DOI: 10.1210/en.2010-0886] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Dopamine (DA)-agonist targeting of the DA D(2) receptor (D2R) in prolactinomas is the first-line treatment choice for suppression of prolactin and induction of tumor shrinkage. Resistance to DA agonists seems to be related to receptor number. Using the MMQ and GH3 pituitary cell lines, that either do or do not express D2R, respectively, we explored the epigenetic profile associated with the presence or absence of D2R in these cells lines. These studies led us to explore pharmacological strategies designed to restore receptor expression and thereby potentially augment DA agonist-mediated apoptosis. We show in GH3 cells that the D2R harbors increased CpG island-associated methylation and enrichment for histone H3K27me3. Conversely, MMQ cells and normal pituitaries show enrichment for H3K9Ac and barely detectable H3K27me3. Coculture of GH3 cells with the demethylating agent zebularine and the histone deacetylase inhibitor trichostatin A was responsible for a decrease in CpG island methylation and enrichment for the histone H3K9Ac mark. In addition, challenge of GH3 cells with zebularine alone or coculture with both agents led to expression of endogenous D2R in these cells. Induced expression D2R in GH3 cells was associated with a significant increase in apoptosis indices to challenge with either DA or bromocriptine. Specificity of a receptor-mediated response was established in coincubations with specific D2R antagonist and siRNA approaches in GH3 cell and D2R expressing MMQ cell lines. These studies point to the potential efficacy of combined treatment with epigenetic drugs and DA agonists for the medical management of different pituitary tumor subtypes, resistant to conventional therapies.
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Varewijck AJ, Goudzwaard JA, Brugts MP, Lamberts SWJ, Hofland LJ, Janssen JAMJL. Insulin glargine is more potent in activating the human IGF-I receptor than human insulin and insulin detemir. Growth Horm IGF Res 2010; 20:427-431. [PMID: 21055982 DOI: 10.1016/j.ghir.2010.10.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2010] [Revised: 09/16/2010] [Accepted: 10/10/2010] [Indexed: 12/28/2022]
Abstract
OBJECTIVE To investigate whether human insulin (HI) and insulin analogues differ in their ability to activate the human IGF-I receptor (IGF-IR), the human insulin receptor A (IR-A) and the human insulin receptor B (IR-B) in vitro. METHODS HI, short-acting insulin analogues (insulin aspart; insulin lispro) and long-acting insulin analogues (insulin glargine; insulin detemir) were compared by using kinase receptor activation (KIRA) bioassays specific for IGF-IR, IR-A or IR-B, respectively. These assays quantify ligand activity by measuring receptor auto-phosphorylation upon ligand binding. HI and insulin analogues were tested in a range from 0.1 to 100 nM. RESULTS Short-acting analogues: Overall, short-acting insulin analogues did not differ substantially from HI, nor from each other. Insulin lispro was slightly more potent than HI and insulin aspart in activating the IGF-IR, only reaching statistical significance at 100 nM (p<0.01). Long-acting analogues: At <10 nM insulin glargine was as potent as HI in activating the IRs and IGF-IR. At 10-100 nM insulin glargine was significantly more potent than HI in activating the IR-B (p<0.05) and IGF-IR (p<0.001). Insulin glargine was more potent than insulin detemir in activating all three receptors (p<0.001). Insulin detemir was less potent than HI in activating the IRs at 1-10 nM (p<0.01) and IGF-IR at >1 nM (p<0.05). CONCLUSIONS Insulin glargine was more potent in activating the IGF-IR than HI and insulin detemir. Since KIRA bioassays do not mimic the exact in vivo situation, further research is needed to find out whether our data have implications for clinical use of insulin glargine.
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Curtò L, Torre ML, Ferraù F, Pitini V, Altavilla G, Granata F, Longo M, Hofland LJ, Trimarchi F, Cannavò S. Temozolomide-induced shrinkage of a pituitary carcinoma causing Cushing's disease--report of a case and literature review. ScientificWorldJournal 2010; 10:2132-8. [PMID: 21057727 PMCID: PMC5763678 DOI: 10.1100/tsw.2010.210] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Temozolomide (TMZ) is an alkylating chemotherapeutic agent that has recently been used in some cases as a new therapeutic tool for pituitary carcinomas and aggressive pituitary adenomas. In this report, we present the case of effective TMZ treatment in a 42-year-old man with ACTH-secreting carcinoma. The tumor grew progressively over 4 years, from 2.2 to 31.1 cm3, despite three surgical approaches and gamma-knife treatment. Ki-67 increased from 2 to 18%. An intradural metastasis at the foramen magnum was detected by MRI after the third operation. Thereafter, four cycles of 5-day TMZ administration (200 mg/m2/day during the first, and 150 mg/m2/day during the following cycles) induced dramatic tumor size reduction (>90%). Clinical conditions improved progressively and, after 17 months from the beginning of TMZ administration, the patient is still alive. The treatment was well tolerated except for a transient thrombocytopenia (grade 4 WHO).
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