Expert consensus document: A consensus on the medical treatment of acromegaly

Resistance training effect on serum insulin-like growth factor 1 in the serum: a meta-analysis

BACKGROUND

The resistance exercise has drawn considerable attention to the level of insulin-like growth factor 1 in the serum. However, the relationship between resistance exercise and the level of insulin-like growth factor 1 in the serum is conflicting. This meta-analysis was performed to evaluate this relationship.

METHODS

A systematic literature search up to May 2020 was performed and 22 studies were detected with 680 subjects. They reported relationships between resistance exercise and the level of insulin-like growth factor 1 in the serum. Odds ratio (OR) with 95% confidence intervals (CIs) was calculated comparing the resistance exercise and the level of insulin-like growth factor 1 in the serum using the continuous method with a random or fixed-effect model.

RESULTS

Significantly higher insulin-like growth factor 1 was observed in subjects performing resistance training for less than 16 weeks (OR, 4.03; 95% CI, 2.49-5.57, p<.001); subjects performing resistance training for more than 16 weeks (OR, 11.55; 95% CI, 6.58-16.52, p<.001); subjects older than 60 years (OR, 11.88; 95% CI, 9.84-13.93, p<.001); females (OR, 3.87; 95% CI, 2.26-5.49, p<.001) and males (OR, 16.82; 95% CI, 7.29-26.35, p<.001). However, significantly lower insulin-like growth factor 1 was observed in subjects younger than 60 years (OR, -4.80; 95% CI, -7.74 to -1.86, p=.001).

CONCLUSIONS

However, the resistance exercise significantly increases insulin-like growth factor 1 in subjects older than 60 years, both males and females, and subjects performing resistance exercise for all any period. Surprisingly, resistance exercise significantly decreases insulin-like growth factor 1 in subjects younger than 60 years. This relationship forces us to recommend the resistance exercise to improve insulin-like growth factor 1 in serum.

Effectiveness of lanreotide autogel 120 mg at extended dosing intervals for acromegaly

PURPOSE

Recent data indicate that extended dosing intervals (EDIs) with lanreotide autogel 120 mg are effective and well-received among patients with acromegaly who have achieved biochemical control with monthly injections of long-acting somatostatin analogues (SSAs). We further evaluated the effectiveness of lanreotide autogel 120 mg delivered at EDIs (>4 weeks) in routine clinical practice.

METHODS

Cross-sectional, multicentre, observational study conducted to determine the effectiveness-measured by control of serum insulin-like growth factor 1 (IGF-1)-of lanreotide autogel 120 mg at dosing intervals >4 weeks for ≥6 months in selected patients with acromegaly treated in routine clinical practice (NCT02807233). Secondary assessments included control of growth hormone (GH) levels, treatment adherence, patient satisfaction, and quality of life (QoL) using validated questionnaires (EQ-5D, AcroQoL, and TSQM-9). Patients who received radiotherapy within the last 6 months were excluded.

RESULTS

Among 109 patients evaluated, mean (SD) age was 59.1 (13.2) years. IGF-1 values were normal (mean [SD]: 175.0 [74.5], 95% CI: 160.8 -189.1) in 91.7% of cases and normal in 91.4% of patients without previous radiotherapy treatment (n = 81). GH levels were ≤2.5 and ≤1 ng/mL, respectively, in 80.6% and 58.3%. Most patients were treated either every 5-6 (57.8%) or 7-8 weeks (38.5%), with 2.8% treated greater than every 8 weeks. The mean AcroQoL score was 63.0 (20.1). The mean global treatment satisfaction score (TSQM-9) was 75.1 (16.6). Treatment adherence (defined as no missed injections) was 94.5%.

CONCLUSION

Lanreotide autogel 120 mg at intervals of >4 weeks provided IGF-1 control in more than 90% of patients with acromegaly. Treatment satisfaction and adherence were good. These findings support use of extended dosing intervals in patients who have achieved good biochemical control with long-acting SSAs.

The significance of estrogen receptors in acromegaly: Are they useful as predictors of prognosis and therapy regimen?

OBJECTIVE

In this study, we considered to assess the presence of estrogen receptors (ER) and the expression of estrogen receptor genes (ESR) in the surgical tissue samples of acromegaly patients and the control group patients with nonfunctioning adenoma and their association with disease activity. We also aimed to determine the significance of ER positivity in acromegaly patients and to find out whether it carries a potential to be used as a predictor of prognosis and therapy regimen in the future.

DESIGN

This study was conducted on a total of 67 patients over 18 years of age. The study group consisted of 34 patients with acromegaly and 33 patients with nonfunctioning pituitary adenoma. The pre- and post-operative basal pituitary hormone levels and magnetic resonance images (MRI) of all patients, as well as their remission status of all acromegaly patients were evaluated. Immunohistochemical (IHC) staining procedures for ER-α were performed on surgical tissue samples. Real-time quantitative polymerase chain reaction (RT-qPCR) method was used to determine the levels of ESR1 and ESR2 gene expressions.

RESULTS

We found that IHC staining for ER-α was positive in 31.3% and 45.5% of the patients with acromegaly and nonfunctioning adenoma respectively. There was no statistically significant difference of ER-α positivity, ER-α immunoreactivity score and ESR1/ESR2 gene expression levels among the study groups (p > .05). Nevertheless, the expression of ESR1 gene was found to be 0.26 times more, and the ESR2 gene to be 0.11 times less in the acromegaly group compared to those of the nonfunctioning adenoma group. Additionally, we detected the positivity of ER-α only in acromegaly patients who were in remission. An inverse association was found between the pre-operative insulin-like growth factor-1 (IGF-1) levels and the expressions of ESR1/ESR2 gene in acromegaly patients. So these results indicated that the high ESR1 and ESR2 gene expressions in acromegaly patients are associated to the decrease of pre-operative IGF-1 values. Also an inverse association was found between the pre-operative adenoma volume and ESR1 Ct values, means that increase in ESR1 gene expression is associated to the decrease of adenoma volume.

CONCLUSIONS

The current results may suggest the use of these parameters as useful prognostic markers because all ER-positive acromegaly patients were in remission and the high ESR1 and ESR2 gene expressions in acromegaly patients is associated to the decrease of pre-operative IGF-1 values. Our results need to be supported by further studies.

Novel therapies for acromegaly

Acromegaly is a systemic disease associated with increased morbidity and mortality. Most of these comorbidities can be prevented or delayed with adequate disease treatment. Although three modalities of treatment (surgery, medical treatment, and radiotherapy) are available and new drugs were approved in the last decades, there are still some patients that maintain disease activity despite treatment. Therefore, there is a need for novel therapies for acromegaly and for that purpose new formulations of currently used drugs and also new drugs are currently under study. In this review, we summarize the novel therapies for acromegaly.

The effects of lycopene supplementation on serum insulin-like growth factor 1 (IGF-1) levels and cardiovascular disease: A dose-response meta-analysis of clinical trials

BACKGROUND

The results of human studies assessing the efficacy of lycopene on insulin-like growth factor 1 (IGF-1) levels are inconsistent. Thus, we performed a systematic review and meta-analysis to examine the effects of lycopene supplementation on serum IGF-1 levels and cardiovascular disease.

METHODS

The literature published up to January 2020 was searched using the electronic databases Scopus, PubMed/Medline, Web of Science, Embase and Google Scholar.

RESULTS

Seven qualified trials were included in the current meta-analysis. IGF-1 levels were non-significantly decreased in lycopene group compared to the control (WMD: -6.74 ng/mL, 95 % CI: -23.01 to 9.52, p = 0.42; I² = 94.3 %). Subgroup analysis revealed a significantly decrease in IGF-1 levels upon lycopene supplementation at doses ≥15 mg/d (WMD: -6.40 ng/mL), intervention period <12 weeks (WMD: -6.49 ng/mL), and subjects aged ≥60 years (WMD: -24.98 mg/dl). In addition, lycopene intake significantly reduced IGF-1 levels upon healthy conditions (WMD: -25.59 ng/mL) when compared with cancer patients (WMD: 0.35 ng/mL). In addition, the effect of lycopene supplementation was significant in patients diagnosed with cardiac disorders.

CONCLUSION

Overall, lycopene intake was not associated with reduced serum IGF-1 levels. However, association was significant when lycopene was administrated at doses >15 mg/d, for <12 weeks, as well as for healthy conditions and patients aged ≥60 years. In addition, lycopene supplementation exhibited potential health benefits in the management of patients with cardiac disorders.

Maintenance of Acromegaly Control in Patients Switching From Injectable Somatostatin Receptor Ligands to Oral Octreotide

PURPOSE

The phase 3 CHIASMA OPTIMAL trial (NCT03252353) evaluated efficacy and safety of oral octreotide capsules (OOCs) in patients with acromegaly who previously demonstrated biochemical control while receiving injectable somatostatin receptor ligands (SRLs).

METHODS

In this double-blind study, patients (N = 56) stratified by prior SRL dose were randomly assigned 1:1 to OOC or placebo for 36 weeks. The primary end point was maintenance of biochemical control at the end of treatment (mean insulin-like growth factor 1 [IGF-1] ≤ 1.0 × upper limit of normal [ULN]; weeks 34 and 36). Time to loss of IGF-1 response and proportion requiring reversion to injectable SRLs were assessed as broader control measures.

RESULTS

Mean IGF-1 measurements were 0.80 and 0.97 × ULN for OOC and 0.84 and 1.69 × ULN for placebo, at baseline and end of treatment, respectively. Mean growth hormone (GH) changed from 0.66 to 0.60 ng/mL for OOCs and 0.90 to 2.57 ng/mL for placebo. Normalization of IGF-1 levels (≤ 1.0 × ULN) was maintained in 58.2% for OOCs vs 19.4% for placebo (P = .008); GH levels were maintained (< 2.5 ng/mL) in 77.7% for OOC vs 30.4% for placebo (P = .0007). Median time to loss of response (IGF-1 > 1.0 or ≥ 1.3 × ULN definitions) for patients receiving placebo was 16 weeks; for patients receiving OOCs, it was not reached for both definitions during the 36-week trial (P < .0001). Of the patients in the OOC group, 75% completed the trial on oral therapy. The OOC safety profile was consistent with previous SRL experience.

CONCLUSIONS

OOCs may be an effective therapy for patients with acromegaly who previously were treated with injectable SRLs.

Two neuroendocrine G protein-coupled receptor molecules, somatostatin and melatonin: Physiology of signal transduction and therapeutic perspectives

Recent studies have shown that G protein-coupled receptors (GPCRs), the largest signal-conveying receptor family, are targets for mutations occurring frequently in different cancer types. GPCR alterations associated with cancer development represent significant challenges for the discovery and the advancement of targeted therapeutics. Among the different molecules that can activate GPCRs, we focused on two molecules that exert their biological actions regulating many typical features of tumorigenesis such as cellular proliferation, survival, and invasion: somatostatin and melatonin. The modulation of signaling pathways, that involves these two molecules, opens an interesting scenario for cancer therapy, with the opportunity to act at different molecular levels. Therefore, the aim of this review is the analysis of the biological activity and the therapeutic potential of somatostatin and melatonin, displaying a high affinity for GPCRs, that interfere with cancer development and maintenance.

Pituitary Tumors Centers of Excellence

Pituitary tumors are common and require complex and sophisticated procedures for both diagnosis and therapy. To maintain the highest standards of quality, it is proposed to manage patients in pituitary tumors centers of excellence (PTCOEs) with patient-centric organizations, with expert clinical endocrinologists and neurosurgeons forming the core. That core needs to be supported by experts from different disciplines such as neuroradiology, neuropathology, radiation oncology, neuro-ophthalmology, otorhinolaryngology, and trained nursing. To provide high-level medical care to patients with pituitary tumors, PTCOEs further pituitary science through research publication, presentation of results at meetings, and performing clinical trials.

Combined therapy of somatostatin analogues with pegvisomant for the treatment of acromegaly: a meta-analysis of prospective studies

BACKGROUND

Acromegaly is a rare, chronic and severe disease. Drug therapy including somatostatin analogues (SAs), dopamine receptor agonists and growth hormone receptor antagonists (pegvisomant, PEG) are commonly used to treat patients who do not respond to surgery. The use of combination therapy with PEG and SAs has become more common over the last decade. We performed this study to accurately evaluate the effect of combination therapy of SAs with PEG on acromegalic patients.

METHODS

PubMed, EMBASE, The Cochrane Library, ClinicalTrials.gov, Scopus, Web of Science, Chinese Biomedical Literature Database and Trip database were searched for relevant studies. Prospective clinical trials treating acromegaly with the co-administration of SAs and PEG were included. We performed a meta-analysis by using Stata 12.1. Sensitivity analysis was conducted to explore heterogeneity.

RESULTS

Nine studies were included in this meta-analysis. The overall rate of serum insulin-like growth factor 1 (IGF-1) normalization was 66% (95% CI: 52-78%; I² = 62.59%). The combination therapy did not significantly change patients' fasting plasma glucose (ES: 0.011 mmol*L^- 1; 95% CI: - 0.374 to 0.397 mmol*L^- 1; P = 0.954) or glycosylated haemoglobin (ES: - 0.074%; 95% CI: - 0.166 to 0.315%; P = 0.544) while decreasing the fasting plasma insulin (ES: - 21.487 pmol*L^-1; 95% CI: - 35.713 to - 7.260 pmol*L^-1; P = 0.003). Elevation of liver enzyme levels was found in 14% (95% CI: 8 to 21%) of the patients. There was no significant difference for serious adverse events and treatment discontinuation due to adverse event between SAs monotherapy group and combination therapy group.

CONCLUSIONS

Combined therapy of SAs and PEG effectively normalized IGF-1 levels in most of the patients whose IGF-1 level was greater than the upper limit of normal after high dose SAs monotherapy. The therapy also decreased significantly FPI levels with a neutral effect on glucose parameters in acromegaly patients. Moreover, elevated liver enzyme levels were observed in a small number of patients, which suggests a need for liver function monitoring.

TRIAL REGISTRATION

We have our protocol registered in PROSPERO. (Registration number: CRD42019115549 ).

Drug treatment strategies for secondary diabetes in patients with acromegaly

INTRODUCTION

Acromegaly is a rare disease due to oversecretion of growth hormone (GH). Even though the disease is often portrayed by its most apparent clinical features, given the abundance of GH receptors throughout the body, it truly is a systemic disease leading to numerous complications and comorbidities. A distinct medical issue in the context of acromegaly is diabetes: It can be a complication as a consequence of GH excess and its mediators, but it can also result from treatment of acromegaly.

AREAS COVERED

This review provides an overview of the effects of acromegaly pathophysiology on glucose homeostasis. Furthermore, it devotes an extensive section on the influence that acromegaly treatment has on glucose metabolism, including approved as well as currently investigated drugs. It also summarizes observations from the use of anti-diabetic medication in patients with acromegaly.

EXPERT OPINION

Glucose imbalance is an important aspect of acromegaly comorbidity and deserves more attention. Even though numerous studies have investigated glucose homeostasis in acromegaly, there is still a clear need for more basic, translational, and also clinical research to advance the understanding of the underlying mechanisms and how to best address them.

CAD/CAM Engineered Patient-Specific Impants as a Reposition Device in Le Fort I and Modified Subcondylar Osteotomies: Case Report of Facial Deformity Correction in Acromegaly

Acromegaly is a medical condition where elevated growth hormone or insulin-like growth factor I levels cause several changes in the craniofacial soft and hard features. We report the correction of facial deformity and posterior open bite with Le Fort I and modified subcondylar osteotomies in a patient affected by acromegaly. Computer-aided design and manufacturing generated saw and drill guides were used to perform osteotomies and segment removal. The placement of the patient-specific implants (PSIs) was guided by predesigned drill holes ensuring the required and planned movement of the jaws and position of the PSIs. After segment removal, the PSIs fitted the predesigned drill holes with high precision and were secured without problems. The planned amount of mandibular and maxillary movement was achieved. The occlusion and osteotomies remained stable for the follow-up of 22 months. The use of PSIs combined with guided surgery can be beneficial for selected cases with asymmetry or posterior open bite enabling new approaches and yielding good functional and aesthetic outcome. The modification of conventional ramus osteotomy combined with utilization of ramus segment removal and the use of PSI for reposition is an interesting and promising technique for rare conditions with ramus height asymmetry.

Assessing the surgical outcome of the "chopsticks" technique in endoscopic transsphenoidal adenoma surgery

OBJECTIVE

The "chopsticks" technique is a 3-instrument, 2-hand mononostril technique that has been recently introduced in endoscopic neurosurgery. It allows a dynamic surgical view controlled by one surgeon only while keeping bimanual dissection. Being a mononostril approach, it requires manipulation of the mucosa of one nasal cavity only. The rationale of the technique is to reduce nasal morbidity without compromising surgical results and complication rates. There are, however, no data available on its results in endoscopic surgery (transsphenoidal surgery [TSS]) for pituitary adenoma.

METHODS

The authors performed a cohort analysis of prospectively collected data on 144 patients (156 operations) undergoing TSS using the chopsticks technique with 3T intraoperative MRI. All patients had at least 3 months of postoperative neurosurgical, endocrinological, and rhinological follow-up (Sino-Nasal Outcome Test-20 [SNOT-20] and Sniffin' Sticks). The surgical technique is described, and the achieved gross-total resection (GTR) and extent of resection (EOR) together with patients' clinical outcomes and complications are descriptively reported.

RESULTS

On 3-month postoperative MRI, GTR was achieved in 71.2% of patients with a mean EOR of 96.7%. GTR was the surgical goal in 122 of 156 cases and was achieved in 106 of 122 (86.9%), with a mean EOR of 98.7% (median 100%, range 49%-100%). There was no surgical mortality. At a median follow-up of 15 months (range 3-70 months), there was 1 permanent neurological deficit. As of the last available follow-up, 11.5% of patients had a new pituitary single-axis deficit, whereas 26.3% had improvement in endocrinological function. Three patients had new postoperative hyposmia. One patient had severe impairment of sinonasal function (SNOT-20 score > 40). The operation resulted in endocrine remission in 81.1% of patients with secreting adenomas.

CONCLUSIONS

This study shows that the chopsticks technique confers resection and morbidity results that compare favorably with literature reports of TSS. This technique permits a single surgeon to perform effective endoscopic bimanual dissection through a single nostril, reducing manipulation of healthy tissue and thereby possibly minimizing surgical morbidity.

Fertility issues in aggressive pituitary tumors

The management of aggressive pituitary adenomas represents a special clinical challenge, and usually involves a combination of surgery, radiotherapy and pharmacological agents to control tumor growth and hormone abnormalities. Fertility is commonly affected in these patients due to compressive effects of the tumor, pituitary hormone dysfunction or as a result of the multiple therapies. The initial approach to restore fertility involves the reduction of tumor volume by the use of dopamine agonists in prolactinomas and by surgery in other pituitary adenomas. Somatostatin analogues are alternative options for GH, ACTH and TSH-secreting tumors. When present, pituitary deficiencies should be appropriately treated, particularly GH deficiency that has been associated with poor pregnancy rates in hypopituitary patients. Other therapies for aggressive pituitary tumors, such as invasive surgery, radiotherapy and temozolamide, may lead to infertility. In such cases, fertility preservation strategies might be considered and discussed with the patient desiring conception before or during treatment. In men and women with hypogonadotropic hypogonadism, administration of gonadotropins or pulse GnRH has resulted in satisfactory pregnancy rates. If spontaneous gestation is not achieved, assisted reproduction techniques can be employed as the last line of treatment. In any context, pre-conception counseling and care are essential as pregnancies in women with aggressive pituitary tumors should always be considered high risk.

Comprehensive circular RNA profiling reveals that hsa_circ_0001368 is involved in growth hormone-secreting pituitary adenoma development

Growth hormone-secreting pituitary adenoma (GHPA) represents about 20% of all histological subtypes of pituitary adenoma (PA), which may result in serious complications and shortened lifespan via growth-hormone (GH) hypersecretion. To date, no biomarkers of early diagnosis or therapeutic targets for GHPA treatment have yet been found. Recently, growing evidence has indicated that circular RNAs (circRNAs) are critical for the development and progression of numerous diseases, including cancers; however, their role in the pathogenesis of GHPA has not been reported. Here, we revealed the expression profile of circRNAs in GHPA using a circRNA microarray, and found 1938 circRNAs were upregulated and 1601 circRNAs were downregulated in GHPA versus normal control. Then the ten most up-regulated circRNAs were selected for the mapping of a circRNA-miRNA-target gene interaction network. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses further indicate that target genes were mostly enriched in the mTOR and the Wnt signaling pathway. Among these differentially expressed circRNAs, hsa_circ_0001368 was verified significant up-regulated by qRT-PCR, which was specific up-regulated in GHPA and correlated with the invasiveness and serum GH level of GHPA; functional studies indicated that knockdown of hsa_circ_0001368 significantly inhibited the proliferation, invasion and GH secreting level of GHPA primary culture cells. Moreover, hsa_circ_0001368 had a significant positive correlation with the pituitary-specific transcription factor Pit-1. In conclusion, our study identified a wealth of candidate circRNAs involved in GHPA and proposed that hsa_circ_0001368 may represent a novel potential biomarker and therapeutic target of GHPA.

Octreotide-Resistant Acromegaly: Challenges and Solutions

Acromegaly is a rare and severe disease caused by an increased and autonomous secretion of growth hormone (GH), thus resulting in high circulating levels of insulin-like growth factor 1 (IGF-1). Comorbidities and mortality rate are closely related to the disease duration. However, in most cases achieving biochemical control means reducing or even normalizing mortality and restoring normal life expectancy. Current treatment for acromegaly includes neurosurgery, radiotherapy and medical therapy. Transsphenoidal surgery often represents the recommended first-line treatment. First-generation somatostatin receptor ligands (SRLs) are the drug of choice in patients with persistent disease after surgery and are suggested as first-line treatment for those ineligible for surgery. However, only about half of patients treated with octreotide (or lanreotide) achieve biochemical control. Other available drugs approved for clinical use are the second-generation SRL pasireotide, the dopamine agonist cabergoline, and the GH-receptor antagonist pegvisomant. In the present paper, we revised the current literature about the management of acromegaly, aiming to highlight the most relevant and recent therapeutic strategies proposed for patients resistant to first-line medical therapy. Furthermore, we discussed the potential molecular mechanisms involved in the variable response to first-generation SRLs. Due to the availability of different medical therapies, the choice for the most appropriate drug can be currently based also on the peculiar clinical characteristics of each patient.

A Consensus on the Diagnosis and Treatment of Acromegaly Comorbidities: An Update

OBJECTIVE

The aim of the Acromegaly Consensus Group was to revise and update the consensus on diagnosis and treatment of acromegaly comorbidities last published in 2013.

PARTICIPANTS

The Consensus Group, convened by 11 Steering Committee members, consisted of 45 experts in the medical and surgical management of acromegaly. The authors received no corporate funding or remuneration.

EVIDENCE

This evidence-based consensus was developed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system to describe both the strength of recommendations and the quality of evidence following critical discussion of the current literature on the diagnosis and treatment of acromegaly comorbidities.

CONSENSUS PROCESS

Acromegaly Consensus Group participants conducted comprehensive literature searches for English-language papers on selected topics, reviewed brief presentations on each topic, and discussed current practice and recommendations in breakout groups. Consensus recommendations were developed based on all presentations and discussions. Members of the Scientific Committee graded the quality of the supporting evidence and the consensus recommendations using the GRADE system.

CONCLUSIONS

Evidence-based approach consensus recommendations address important clinical issues regarding multidisciplinary management of acromegaly-related cardiovascular, endocrine, metabolic, and oncologic comorbidities, sleep apnea, and bone and joint disorders and their sequelae, as well as their effects on quality of life and mortality.

Predictive factors for responses to primary medical treatment with lanreotide autogel 120 mg in acromegaly: post hoc analyses from the PRIMARYS study

PURPOSE

PRIMARYS (NCT00690898) was a 48-week, open-label, phase 3b study, evaluating treatment with the somatostatin receptor ligand lanreotide autogel (stable dose: 120 mg/28 days) in treatment-naïve patients with growth hormone (GH)-secreting pituitary macroadenoma. This post hoc analysis aimed to evaluate factors predictive of long-term responses.

METHODS

Potential predictive factors evaluated were: sex, age, and body mass index at baseline; and GH, insulin-like growth factor-1 (IGF-1), and tumor volume (TV) at baseline and week 12, using univariate regression analyses. Treatment responses were defined as hormonal control (GH ≤ 2.5 µg/L and age- and sex-normalized IGF-1), tight hormonal control (GH < 1.0 µg/L and normalized IGF-1), or ≥ 20% TV reduction (TVR). Receiver-operating-characteristic (ROC) curves were constructed using predictive factors significant in univariate analyses. Cut-off values for predicting treatment responses at 12 months were derived by maximizing the Youden index (J).

RESULTS

At baseline, older age, female sex, and lower IGF-1 levels were associated with an increased probability of achieving long-term hormonal control. ROC area-under-the curve (AUC) values for hormonal control were high for week-12 GH and IGF-1 levels (0.87 and 0.93, respectively); associated cut-off values were 1.19 μg/L and 110% of the upper limit of normal (ULN), respectively. Results were similar for tight hormonal control (AUC values: 0.92 [GH] and 0.87 [IGF-1]; cut-off values: 1.11 μg/L and 125% ULN, respectively). AUC and J values associated with TVR were low.

CONCLUSIONS

The use of predictive factors at baseline and week 12 of treatment could inform clinical expectations of the long-term efficacy of lanreotide autogel.

Effects of Pegvisomant and Pasireotide LAR on Vertebral Fractures in Acromegaly Resistant to First-generation SRLs

PURPOSE

Osteopathy is an emerging complication of acromegaly. In somatostatin receptor ligands (SRL)-resistant patients, pegvisomant (PegV) and pasireotide LAR (Pasi) are used for acromegaly treatment, but their effect on skeletal health is still not defined.

METHODS

In a longitudinal retrospective international study, we evaluated incidence of radiological vertebral fractures (VFs) in 55 patients with acromegaly resistant to first-generation SRL.

RESULTS

At study entry, prevalent VFs occurred in 23 patients (41.8%). Biochemical acromegaly control was reached in 66.7% of patients on PegV and in 66.7% of patients on Pasi. During the follow-up, incident VFs (iVFs) were detected in 16 patients (29.1%). Occurrence of iVFs was associated with prevalent VFs (P = .002), persistence of active acromegaly (P = .01) and higher value of insulin-like growth factor 1 (IGF-1) during follow-up (P = .03). Among patients with active disease at last visit, iVFs occurred less frequently in patients on treatment with Pasi (25%) compared to PegV (77.8% P = .04), independently of the IGF-1 values (P = .90). In patients who reached biochemical control, 22.7% on PegV and 12.5% on Pasi had iVFs (P = .40). Among both treatment groups, the presence of pre-existent VFs was the main determinant for iVFs.

CONCLUSION

Our data show for the first time that patients with biochemically active disease treated with Pasi had lower risk of iVFs versus those treated with PegV. It also confirms that the presence of pre-existent VFs was the main determinant for iVFs. Additional studies on larger populations and with longer follow-up are needed to confirm our data and disclose the mechanisms underlying our findings.

Somatostatin Analogs in Clinical Practice: a Review

Somatostatin analogs are an invaluable therapeutic option in the diagnosis and treatment of somatotropinomas, thyrotropinomas, and functioning and non-functioning gastroenteropancreatic neuroendocrine tumors. They should also be considered an effective and safe therapeutic alternative to corticotropinomas, gonadotropinomas, and prolactinomas resistant to dopamine agonists. Somatostatin analogs have also shown to be useful in the treatment of other endocrine diseases (congenital hyperinsulinism, Graves’ orbitopathy, diabetic retinopathy, diabetic macular edema), non-endocrine tumors (breast, colon, prostate, lung, and hepatocellular), and digestive diseases (chronic refractory diarrhea, hepatorenal polycystosis, gastrointestinal hemorrhage, dumping syndrome, and intestinal fistula).

Integration of Spiritual Care in Hospital Care System in Iran

There is a growing body of evidence on the positive effects of religion and spirituality on recovery from cancer and the ability to cope with it. Most spiritual interventions carried out in Iranian research are based on care and support models that have been developed in the West. With the unique cultural and religious features of the Iranian context, a more refined look at spiritual care in the hospital care system of Iran is called for. This paper examines how to implement the spiritual care of cancer patients in hospitals and oncology wards in Iran. A consensus panel of experts was used to develop guidelines for spiritually integrated care consisting of 18 primary areas, which are described in detail in this report. Health care policy makers and managers of health care in Iran and possibly other areas of the Middle East should consider implementing these guidelines. Using indigenous models and programs specific to the religion and the cultural of a region should be considered when providing spiritual care for cancer patients.

Pituitary Adenomas: What Are the Key Features? What Are the Current Treatments? Where Is the Future Taking Us?

Pituitary tumors are a heterogeneous group of lesions (usually benign) and proper understanding of the anatomy, physiology, and pathology of the hypothalamic/pituitary region is essential to make an accurate diagnosis and define the essential treatment options (i.e., surgery, medical therapies, and radiotherapy, alone or in combination). Surgery is the primary treatment for acromegaly, Cushing disease, thyroid-stimulating hormone-secreting adenomas, resistant prolactinomas, and nonfunctioning pituitary adenomas causing mass effect. Medical and radiation therapy are reserved in cases in which surgery is not possible or does not provide a complete cure. In the last decades, tremendous innovations (i.e., targeted drugs and refined surgical tools and techniques) have expanded the treatment strategies for pituitary adenomas. We herein report the current indications for and depiction of the surgical techniques in pituitary surgery, review current medical treatments, and provide a glimpse of future possibilities.

Italian Association of Clinical Endocrinologists (AME) and Italian AACE Chapter Position Statement for Clinical Practice: Acromegaly - Part 1: Diagnostic and Clinical Issues

Acromegaly is a rare disease. Improvements in lifespan in these patients have recently been reported due to transsphenoidal surgery (TSS), advances in medical therapy, and strict criteria for defining disease remission. This document reports the opinions of a group of Italian experts who have gathered together their prolonged clinical experience in the diagnostic and therapeutic challenges of acromegaly patients. Both GH and IGF-I (only IGF-I in those treated with Pegvisomant) are needed in the diagnosis and follow-up. Comorbidities (cardio-cerebrovascular disease, sleep apnea, metabolic derangement, neoplasms, and bone/joint disease) should be specifically addressed. Any newly diagnosed patient should be referred to a multidisciplinary team experienced in the treatment of pituitary adenomas.

Development of an UPLC/MS–MS method for quantification of intact IGF-I from human serum

Aim: Developing LC–MS methods for biomolecules is often challenging due to issues with molecular size and complexity, nonspecific binding, protein binding, solubility and sensitivity. As a result, complex sample preparation workflows, including immune-affinity and/or protein digestion and lengthy analysis potentially using nano-flow LC, may be needed to achieve the required sensitivity. This work aims to provide a simple, sensitive, fast and robust method for quantification of intact IGF-I from human serum using UPLC–MS/MS. Methods: IGF-I serum samples were denatured with sodium dodecyl sulfate, followed by organic protein precipitation to effectively disrupt protein binding and subsequent SPE of the resulting supernatant for sample cleanup and enrichment prior to LC–MS/MS analysis. Separation was performed on an analytical scale LC using a reversed-phase column containing <2 μm solid core particle followed by detection on a tandem quadrupole MS in multiple reaction monitoring mode. Results: Intact IGF-I was quantified from serum using the method described above at a LLOQ of 5 ng/ml with a dynamic range 5–1000 ng/ml (r2>0.99) and mean accuracy of 101.76%. Accuracies for quality control samples were between 93.9–107.7% with RSD <7%. Conclusion: The analytical sensitivity, linear dynamic range and excellent reproducibility of this method reliably measures endogenous and elevated serum IGF-I levels, demonstrating its utility in discovery, bioanalysis and clinical research.

Insulin-like growth factor 1 modulates the phosphorylation, expression, and activity of organic anion transporter 3 through protein kinase A signaling pathway

Organic anion transporter 3 (OAT3) plays a vital role in removing a broad variety of anionic drugs from kidney, thus avoiding their possible toxicity in the body. In the current study, we investigated the role of insulin-like growth factor 1 (IGF-1) in the regulation of OAT3. We showed that IGF-1 induced a dose- and time-dependent increase in OAT3 transport activity, which correlated well with an increase in OAT3 expression. The IGF-1-induced increase in OAT3 expression was blocked by protein kinase A (PKA) inhibitor H89. Moreover, IGF-1 induced an increase in OAT3 phosphorylation, which was also blocked by H89. These data suggest that the IGF-1 modulation of OAT3 occurred through PKA signaling pathway. To further confirm the involvement of PKA, we treated OAT3-expressing cells with PKA activator Bt2-cAMP, followed by examining OAT activity and phosphorylation. We showed that OAT3 activity and phosphorylation were much enhanced in Bt2-cAMP-treated cells as compared to that in control cells. Finally, linsitinib, an anticancer drug that blocks the IGF-1 receptor, abrogated IGF-1-stimulated OAT3 transport activity. In conclusion, our study demonstrated that IGF-1 regulates OAT3 expression and transport activity through PKA signaling pathway, possibly by phosphorylating the transporter.

Italian Association of Clinical Endocrinologists (AME) and Italian AACE Chapter Position Statement for Clinical Practice: Acromegaly - Part 2: Therapeutic Issues

Any newly diagnosed patient should be referred to a multidisciplinary team experienced in the treatment of pituitary adenomas. The therapeutic management of acromegaly always requires a personalized strategy. Normal age-matched IGF-I values are the treatment goal. Transsphenoidal surgery by an expert neurosurgeon is the primary treatment modality for most patients, especially if there are neurological complications. In patients with poor clinical conditions or who refuse surgery, primary medical treatment should be offered, firstly with somatostatin analogs (SSAs). In patients who do not reach hormonal targets with first-generation depot SSAs, a second pharmacological option with pasireotide LAR or pegvisomant (alone or combined with SSA) should be offered. Irradiation could be proposed to patients with surgical remnants who would like to be free from long-term medical therapies or those with persistent disease activity or tumor growth despite surgery or medical therapy. Since the therapeutic tools available enable therapeutic targets to be achieved in most cases, the challenge is to focus more on the quality of life.

Reversibility of Cardiac Involvement in Acromegaly Patients After Surgery: 12-Month Follow-up Using Cardiovascular Magnetic Resonance

PURPOSE

Cardiac comorbidity is one of the leading causes of death among acromegaly patients. We aimed to investigate the reversibility of acromegalic cardiac involvement after surgical treatment using the gold standard method, cardiovascular magnetic resonance, and to explore the effects of endocrine remission and gender on reversibility.

METHODS

In this single-center, prospective cohort study, fifty untreated acromegaly patients were enrolled. Comprehensive cardiac assessments were performed using a 3.0 T magnetic resonance scanner before and 3 and 12 months after transsphenoidal adenomectomy.

RESULTS

Preoperatively, left ventricular (LV) enlargement (13.0%), LV systolic dysfunction (6.5%), right ventricular (RV) enlargement (4.3%), RV systolic dysfunction (2.2%) and myocardial fibrosis (12.0%) were identified. On average, the LV and RV ejection fractions of acromegaly patients were higher than the healthy reference values. Male patients had thicker LV myocardia, wider ventricular diameters and more dilated pulmonary artery roots than female patients. After surgery, LV myocardial hypertrophy was reversed, the left atrium was remodeled, and ventricular systolic dysfunction recovered to normal. Cardiac alterations were detected early in the 3^rd postoperative month and persisted until the 12^th month. The interventricular septum was initially thickened in the 3^rd postoperative month and then recovered at the 12th month. Notable postoperative cardiac reversibility was observed in male patients but did not occur in all female patients. Patients achieving endocrine remission with normalized hormone levels had thinner LV myocardia than patients without normalized hormone levels.

CONCLUSION

Our findings demonstrated that some of the cardiac involvement in acromegaly patients is reversible after surgical treatment which lowers hormone levels. Endocrine remission and gender significantly impacted postoperative cardiac reversibility.

The position of combined medical treatment in acromegaly

Advances in combination medical treatment have offer new perspectives for acromegaly patients with persistent disease activity despite receiving the available medical monotherapies. The outcomes of combination medical treatment may reflect both additive and synergistic effects. This review focuses on combination medical treatment and its current position in acromegaly, based on clinical studies evaluating the efficacy and safety of combined medical treatment(s) and our own experiences with combination therapy. Arch Endocrinol Metab. 2019;63(6):646-52.

Hepatic steatosis in patients with acromegaly

OBJECTIVE

Comorbid NAFLD is increasingly being diagnosed in patients with diabetes and nondiabetic endocrinopathies. The aim of this study was to assess hepatic steatosis noninvasively by transient elastography in patients with acromegaly.

DESIGN

A cross-sectional study including 22 patients with acromegaly.

METHODS

Hepatic steatosis was quantified using controlled attenuation parameter (CAP) during elastography. Anthropometric measurements were obtained, serum liver function tests and lipid and hormone profiles were measured, and prosteatogenic gene variants were genotyped using standard assays.

RESULTS

In total, 41% of patients were women (mean age 60 ± 14.7 years, mean BMI 31.2 ± 4.6 kg/m2). Hepatic steatosis, as defined by CAP > 248 dB/m, was present in 66% of patients. Five (45%) of the patients with hepatic steatosis also had fibrosis, and one presented with cirrhosis. Nine patients were carriers of the PNPLA3 p.I148M prosteatogenic [M] risk allele, eight of whom were heterozygotes. CAP values were significantly (P = .045) higher in these patients and corresponded to advanced steatosis, as compared to patients with the wild-type genotype, who demonstrated CAP values consistent with mild steatosis (311 ± 33 dB/m. vs 254 ± 62 dB/m). CAP values did not differ significantly in carriers of distinct TM6SF2 and MBOAT7 genotypes; however, carriers of the risk alleles displayed higher CAP as compared to wild-type patients.

CONCLUSIONS

This study shows that in patients with acromegaly, carriers of the PNPLA3 susceptibility allele are at risk of developing hepatic steatosis, as assessed by CAP. Comorbid NAFLD might compound prognosis in such patients; thus, further research into the pathomechanisms and treatment of NAFLD in acromegaly is warranted.

Current perspectives on the impact of clinical disease and biochemical control on comorbidities and quality of life in acromegaly

Acromegaly is a rare chronic, systemic disorder caused by excessive growth hormone (GH) secretion from a somatotroph pituitary adenoma. GH hypersecretion leads to overproduction of insulin-like growth factor-1 (IGF-1), which contributes to the somatic overgrowth, physical disfigurement, onset of multiple systemic comorbidities, reduced quality of life (QoL) and premature mortality of uncontrolled patients. Somatostatin receptor ligands, dopamine agonists and a GH receptor antagonist are currently available for medical therapy of acromegaly. The main aim of treatment is biochemical normalisation, defined as age-normalised serum IGF-1 values and random GH levels <1.0 μg/L. However, there is an increasing evidence suggesting that achieving biochemical control does not always decrease the burden of disease-related comorbidities and/or improve patients' QoL. This lack of correlation between biochemical and clinical control can be due to both disease duration (late diagnosis) or to the peculiarity of a given comorbidity. Herein we conducted ad hoc literature searches in order to find the most recent and relevant reports on biochemical and clinical disease control during medical treatment of acromegaly. Particularly, we analyse and describe the relationship between biochemical, as well as clinical disease control in patients with acromegaly receiving medical therapy, with a focus on comorbidities and QoL. In conclusion, we found that current literature data seem to indicate that clinical disease control (besides biochemical control), encompassing clinical signs and symptoms, comorbidities and QoL, emerge as a primary focus of acromegaly patient management.

Pegvisomant in acromegaly: a multicenter real-life study in Argentina

OBJECTIVE

To describe the long term safety and efficacy of pegvisomant (PEGV), and the predictors of treatment response in patients with acromegaly in the real life setting.

SUBJECTS AND METHODS

We retrospectively reviewed the clinical, hormonal and radiological data of acromegalic patients treated with PEGV in 17 Argentine centers.

RESULTS

Seventy-five patients (age range 22-77, 51 females) with acromegaly have been treated with PEGV for up to 118 months (median 27 months). Before PEGV, 97.3% of patients had been treated with medical therapy, surgery and/or radiotherapy, two patients had no previous treatment. At that time, all patients had an IGF-1 above the upper normal limit (ULN) (mean 2.4 x ULN ± 0.98, range 1.25-7). At diagnosis of acromegaly 84% presented macroadenomas, prior to PEGV only 23,5% of patients remained with tumor remnant > 1 cm, the remaining showed normal or less than 1 cm images. Disease control (IGF-1 ≤ 1.2 x ULN) was achieved in 62.9% of patients with a mean dose of 11.8 mg/day. Thirty-four patients (45%) received PEGV monotherapy, while 41 (55%) received combined therapy with either somatostatin analogues and/or cabergoline. Adverse events related to PEGV were: local injection site reaction in 5.3%, elevated liver enzymes in 9.3%, and tumor size growth in 9.8%. Pre-PEGV IGF-I level was the only predictor of treatment response: 2.1 x ULN vs 2.8 x ULN in controlled and uncontrolled patients respectively (p < 0.001).

CONCLUSION

this long term experience indicates PEGV treatment was highly effective and safe in our series of Argentine patients with acromegaly refractory to standard therapies. Arch Endocrinol Metab. 2019;63(4):320-7.

Biological and Biochemical Basis of the Differential Efficacy of First and Second Generation Somatostatin Receptor Ligands in Neuroendocrine Neoplasms

Endogenous somatostatin shows anti-secretory effects in both physiological and pathological settings, as well as inhibitory activity on cell growth. Since somatostatin is not suitable for clinical practice, researchers developed synthetic somatostatin receptor ligands (SRLs) to overcome this limitation. Currently, SRLs represent pivotal tools in the treatment algorithm of neuroendocrine tumors (NETs). Octreotide and lanreotide are the first-generation SRLs developed and show a preferential binding affinity to somatostatin receptor (SST) subtype 2, while pasireotide, which is a second-generation SRL, has high affinity for multiple SSTs (SST₅ > SST₂ > SST₃ > SST₁). A number of studies demonstrated that first-generation and second-generation SRLs show distinct functional properties, besides the mere receptor affinity. Therefore, the aim of the present review is to critically review the current evidence on the biological effects of SRLs in pituitary adenomas and neuroendocrine tumors, by mainly focusing on the differences between first-generation and second-generation ligands.

Endocrine Outcomes After Pituitary Surgery

Although removal of pituitary tumors yields excellent surgical outcomes, perturbations in the hypothalamic-pituitary axis are not uncommon. Careful assessment of postoperative hormone status with supplementation or further medical therapy is critical to successful outcomes. Although many centers routinely use perioperative steroids, they can be associated with worse outcomes in the absence of intact preoperative adrenal function or damage to the pituitary gland or stalk during surgery. Postoperative assessment of prolactin, cortisol, and growth hormone can be prognostic of surgical cure. Hormonal axes should be reevaluated routinely several weeks after surgery, because longitudinal monitoring is important for surgical and medical outcomes.

GSTP1 gene methylation and AHR rs2066853 variant predict resistance to first generation somatostatin analogs in patients with acromegaly

PURPOSE

Biomarkers of clinical and therapeutic outcome in acromegaly are needed. Polymorphisms or epigenetic changes of detoxification genes, such as those coding for the aryl hydrocarbon receptor (AHR) and the glutathione-S-transferase-P1 (GSTP1), could have a role in GH secreting pituitary tumors' pathophysiology and clinical expression. In this study, we assessed the contribution of GSTP1 gene promoter methylation status, per se or in combination with the occurrence of the AHR gene rs2066853 variant, on clinical features and response to somatostatin analogs (SSA) treatment in acromegaly patients.

METHODS

This is an observational, retrospective study, carried out in the Endocrine Unit of an Italian University Hospital. We enrolled 77 wild-type AIP gene acromegaly patients, who have been screened for germline AHR rs2066853 variant and GSTP1 gene promoter methylation. Clinical and biochemical parameters were compared after patients' stratification according to GSTP1 methylation status and the presence of AHR rs2066853. We also evaluated the response to SSA treatment in 71 cases.

RESULTS

17 patients carried the AHR rs2066853 variant and 26 had methylated GSTP1 (GSTP1-methyl) gene promoter. GSTP1-methyl patients showed a higher prevalence of diabetes mellitus (p = 0.01), colonic polyps (p = 0.05), and were more resistant to SSA (p = 0.02) as compared to GSTP1 unmethylated patients (GSTP1-unmethyl). Patients GSTP1-unmethyl and AHR wild-type were the most sensitive to SSA treatment, while those with both GSTP1-methyl and AHR rs2066853 variant were all resistant to SSA (p = 0.01).

CONCLUSIONS

In acromegaly, GSTP1 gene methylation associates with resistance to SSA treatment, especially in patients carrying also the AHR rs2066853 variant, and with increased prevalence of colonic polyps and diabetes mellitus.

Growth hormone and prolactin-staining tumors causing acromegaly: a retrospective review of clinical presentations and surgical outcomes

OBJECTIVE

Acromegaly results in disfiguring growth and numerous medical complications. This disease is typically caused by growth hormone (GH)-secreting pituitary adenomas, which are treated first by resection, followed by radiation and/or medical therapy if needed. A subset of acromegalics have dual-staining pituitary adenomas (DSPAs), which stain for GH and prolactin. Presentations and treatment outcomes for acromegalics with DSPAs are not well understood.

METHODS

The authors retrospectively reviewed the records of more than 5 years of pituitary adenomas resected at their institution. Data were collected on variables related to clinical presentation, tumor pathology, radiological size, and disease recurrence. The Fisher's exact test, ANOVA, Student t-test, chi-square test, and Cox proportional hazards and multiple logistic regression were used to measure statistical significance.

RESULTS

Of 593 patients with pituitary adenoma, 91 presented with acromegaly. Of these 91 patients, 69 (76%) had tumors that stained for GH only (single-staining somatotrophic adenomas [SSAs]), while 22 (24%) had tumors that stained for GH and prolactin (DSPAs). Patients with DSPAs were more likely to present with decreased libido (p = 0.012), signs of acromegalic growth (p = 0.0001), hyperhidrosis (p = 0.0001), and headaches (p = 0.043) than patients with SSAs. DSPAs presented with significantly higher serum prolactin (60.7 vs 10.0 µg/L, p = 0.0002) and insulin-like growth factor-1 (IGF-1) (803.6 vs 480.0 ng/ml, p = 0.0001), and were more likely to have IGF-1 levels > 650 ng/ml (n = 13 [81.3%] vs n = 6 [21.4%], p = 0.0001) than patients with SSAs despite similar sizes (1.8 vs 1.7 cm, p = 0.5). Patients with DSPAs under 35 years of age were more likely to have a recurrence (n = 4 [50.0%] vs n = 3 [11.1%], p = 0.01) than patients with SSAs under the age of 35. DSPA patients were less likely to achieve remission with surgery than SSA patients (n = 2 [20%] vs n = 19 [68%], p = 0.01). Univariate analysis identified single-staining tumors (p = 0.02), gross-total resection (p = 0.02), and tumor diameter (p = 0.05) as predictors of surgical remission. Multiple logistic regression demonstrated that SSAs (p = 0.04) were independently associated with surgical remission of acromegaly. Kaplan-Meier analysis revealed that DSPAs had more time until disease remission (p = 0.033).

CONCLUSIONS

Acromegalics with tumors that stain for prolactin and GH, which represented almost a quarter of acromegalics in this cohort, had more aggressive clinical presentations and postoperative outcomes than SSAs. Prolactin staining provides useful information for acromegalics undergoing pituitary surgery.

How to Position Pasireotide LAR Treatment in Acromegaly

CONTEXT

Pasireotide long-acting release (LAR) is a somatostatin multireceptor ligand, and in the current consensus criteria pasireotide LAR is considered the second-line medical treatment for acromegaly. We present in this article our recommendations to define the position of pasireotide LAR in the treatment of acromegaly and provide recommendations for the management of pasireotide-induced hyperglycemia.

EVIDENCE ACQUISITION

Our recommendations are based on our experiences with the pasireotide LAR and pegvisomant (PEGV) combination study and the available basic or clinical articles published in peer-reviewed international journals on pasireotide LAR and acromegaly.

EVIDENCE SYNTHESIS

In accordance with the current consensus criteria, we recommend pasireotide LAR monotherapy as a second-line therapy in young patients who show tumor growth during first-generation somatostatin receptor ligand (SRL) therapy and in patients who show tumor growth during PEGV therapy. In addition, we recommend pasireotide LAR monotherapy in patients with headache not responsive to first-generation SRL therapy and in patients who experience side effects or are intolerant to PEGV monotherapy. In contrast to the current consensus criteria, we recommend considering combination therapy with pasireotide LAR and PEGV as third-line treatment in patients without diabetes at low PEGV dosages (≤80 mg/week) and in patients with tumor growth or symptoms of active acromegaly during first-generation SRL and PEGV combination therapy. With respect to pasireotide-induced hyperglycemia, we recommend a more liberal strategy of blood glucose monitoring during pasireotide treatment.

CONCLUSIONS

In contrast to the current consensus criteria, we recommend a more reluctant use of pasireotide LAR therapy for the treatment of acromegaly.

Hypermethylator Phenotype and Ectopic GIP Receptor in GNAS Mutation-Negative Somatotropinomas

CONTEXT

Besides GNAS gene mutations, the molecular pathogenesis of somatotroph adenomas responsible for gigantism and acromegaly remains elusive.

OBJECTIVE

To investigate alternative driver events in somatotroph tumorigenesis, focusing on a subgroup of acromegalic patients with a paradoxical increase in growth hormone (GH) secretion after oral glucose, resulting from ectopic glucose-dependent insulinotropic polypeptide receptor (GIPR) expression in their somatotropinomas.

DESIGN, SETTING, AND PATIENTS

We performed combined molecular analyses, including array-comparative genomic hybridization, RNA/DNA fluorescence in situ hybridization, and RRBS DNA methylation analysis on 41 somatotropinoma samples from 38 patients with acromegaly and three sporadic giants. Ten patients displayed paradoxical GH responses to oral glucose.

RESULTS

GIPR expression was detected in 13 samples (32%), including all 10 samples from patients with paradoxical GH responses. All GIPR-expressing somatotropinomas were negative for GNAS mutations. GIPR expression occurred through transcriptional activation of a single allele of the GIPR gene in all GIPR-expressing samples, except in two tetraploid samples, where expression occurred from two alleles per nucleus. In addition to extensive 19q duplications, we detected in four samples GIPR locus microamplifications in a certain proportion of nuclei. We identified an overall hypermethylator phenotype in GIPR-expressing samples compared with GNAS-mutated adenomas. In particular, we observed hypermethylation in the GIPR gene body, likely driving its ectopic expression.

CONCLUSIONS

We describe a distinct molecular subclass of somatotropinomas, clinically revealed by a paradoxical increase of GH to oral glucose related to pituitary GIPR expression. This ectopic GIPR expression occurred through hypomorphic transcriptional activation and is likely driven by GIPR gene microamplifications and DNA methylation abnormalities.

Unmasking a new prognostic marker and therapeutic target from the GDNF-RET/PIT1/p14ARF/p53 pathway in acromegaly

Background

Acromegaly is produced by excess growth hormone secreted by a pituitary adenoma of somatotroph cells (ACRO). First-line therapy, surgery and adjuvant therapy with somatostatin analogs, fails in 25% of patients. There is no predictive factor of resistance to therapy. New therapies are investigated using few dispersed tumor cells in acute primary cultures in standard conditions where the cells do not grow, or using rat pituitary cell lines that do not maintain the full somatotroph phenotype. The RET/PIT1/p14ARF/p53 pathway regulates apoptosis in normal pituitary somatotrophs whereas the RET/GDNF pathway regulates survival, controlling PIT1 levels and blocking p14ARF (ARF) and p53 expression.

Methods

We investigated these two RET pathways in a prospective series of 32 ACRO and 63 non-functioning pituitary adenomas (NFPA), studying quantitative RNA and protein gene expression for molecular-clinical correlations and how the RET pathway might be implicated in therapeutic success. Clinical data was collected during post-surgical follow-up. We also established new'humanized’ pituitary cultures, allowing 20 repeated passages and maintaining the pituitary secretory phenotype, and tested five multikinase inhibitors (TKI: Vandetanib, Lenvatinib, Sunitinib, Cabozantinib and Sorafenib) potentially able to act on the GDNF-induced RET dimerization/survival pathway. Antibody arrays investigated intracellular molecular pathways.

Findings

In ACRO, there was specific enrichment of all genes in both RET pathways, especially GDNF. ARF and GFRA4 gene expression were found to be opposing predictors of response to first-line therapy. ARF cut-off levels, calculated categorizing by GNAS mutation, were predictive of good response (above) or resistance (below) to therapy months later. Sorafenib, through AMPK, blocked the GDNF/AKT survival action without altering the RET apoptotic pathway.

Interpretation

Tumor ARF mRNA expression measured at the time of the surgery is a prognosis factor in acromegaly. The RET inhibitor, Sorafenib, is proposed as a potential treatment for resistant ACRO.

Fund

This project was supported by national grants from Agencia Estatal de Investigación (AEI) and Instituto Investigación Carlos III, with participation of European FEDER funds, to IB (PI150056) and CVA (BFU2016-76973-R). It was also supported initially by a grant from the Investigator Initiated Research (IIR) Program (WI177773) and by a non-restricted Research Grant from Pfizer Foundation to IB. Some of the pituitary acromegaly samples were collected in the framework of the Spanish National Registry of Acromegaly (REMAH), partially supported by an unrestricted grant from Novartis to the Spanish Endocrine Association (SEEN).

CVA is also supported from a grant of Medical Research Council UK MR/M018539/1.

National acromegaly registries

Acromegaly is a rare disease, associated with multiple organs and systems damage. Thanks to implementation of registries, systematic data gathering, knowledge sharing and standardizing medical practices for optimal care greatly improved. Data concerning 19 national acromegaly registries are available, involving more than 16,000 patients. The weighted mean age of diagnosis is 45.2 years and seems stable over time. A macroadenoma is found in 75% of the cases. The proportion of patients operated (>80%) did not change along time. By contrast, use of radiotherapy has decreased while use of medical therapy increased. If judged on IGF-I levels, acromegaly is controlled in 61.3% of the patients. The disease control rate has improved over time. This is likely due to the development of medical treatment strategies. The collection of data about comorbidities in national registries is much less comprehensive than those about epidemiology, disease control or treatment strategies. The most reported comorbidities are arterial hypertension and diabetes. Data concerning mortality trends are controversial. It seems that cancer has become a leading cause of death in acromegaly patients in the last decade, period in which life expectancy improved, while cardiovascular mortality decreased. In conclusion, acromegaly registries offer a global view of the disease with no "a priori" assumptions. This is of outmost importance, because of the large amount of data and the huge number of associated comorbidities. This will help to establish guidelines for management of this rare disease.

AIP and MEN1 mutations and AIP immunohistochemistry in pituitary adenomas in a tertiary referral center

BACKGROUND

Pituitary adenomas have a high disease burden due to tumor growth/invasion and disordered hormonal secretion. Germline mutations in genes such as MEN1 and AIP are associated with early onset of aggressive pituitary adenomas that can be resistant to medical therapy.

AIMS

We performed a retrospective screening study using published risk criteria to assess the frequency of AIP and MEN1 mutations in pituitary adenoma patients in a tertiary referral center.

METHODS

Pituitary adenoma patients with pediatric/adolescent onset, macroadenomas occurring ≤30 years of age, familial isolated pituitary adenoma (FIPA) kindreds and acromegaly or prolactinoma cases that were uncontrolled by medical therapy were studied genetically. We also assessed whether immunohistochemical staining for AIP (AIP-IHC) in somatotropinomas was associated with somatostatin analogs (SSA) response.

RESULTS

Fifty-five patients met the study criteria and underwent genetic screening for AIP/MEN1 mutations. No mutations were identified and large deletions/duplications were ruled out using MLPA. In a cohort of sporadic somatotropinomas, low AIP-IHC tumors were significantly larger (P = 0.002) and were more frequently sparsely granulated (P = 0.046) than high AIP-IHC tumors. No significant relationship between AIP-IHC and SSA responses was seen.

CONCLUSIONS

Germline mutations in AIP/MEN1 in pituitary adenoma patients are rare and the use of general risk criteria did not identify cases in a large tertiary-referral setting. In acromegaly, low AIP-IHC was related to larger tumor size and more frequent sparsely granulated subtype but no relationship with SSA responsiveness was seen. The genetics of pituitary adenomas remains largely unexplained and AIP screening criteria could be significantly refined to focus on large, aggressive tumors in young patients.

Use of administrative health databases to estimate incidence and prevalence of acromegaly in Piedmont Region, Italy

PURPOSE

Recent studies from national registries have described changing patterns in epidemiology of acromegaly. Our retrospective study used administrative databases to estimate prevalence and incidence of acromegaly in the Piedmont Region, Italy.

METHODS

This study was conducted in Piedmont between 2012 and 2016 on administrative health databases for inpatients and outpatients of any age. Enrollees were included if claims suggestive of acromegaly were identified in at least two of the following databases: Drug Claims Registry, Hospital Information System, Co-payment Exemption Registry and Outpatient Specialist Service Information System.

RESULTS

369 individuals (M = 146, F = 223) met our criteria. Overall incidence was 5.3 per million person years (95% CI 4.2-6.7), and prevalence was 83 cases per million inhabitants (95% CI 75-92). Mean age was 50.9 years. Both incidence and prevalence were slightly higher among women (rate ratio 1.08, prevalence ratio 1.43). Age-specific incidence was similar between sexes up to 39 years and diverged thereafter, with an increasing trend recorded among men. Prevalence was higher in women aged 40-79 years, and increased continuously up to 79 years in both sexes.

CONCLUSIONS

This is the first population-based study conducted in Italy to estimate incidence and prevalence of acromegaly and results show a higher prevalence than previously reported. Although our algorithm requires proper validation, it constitutes a promising tool to describe the epidemiology of acromegaly.

The burden of disease for pituitary patients

Pituitary diseases are rare conditions with severe chronic multiorgan and multisystemic morbidity requiring complex multidisciplinary treatment and usually life-long drug treatment. Most cases are caused by functioning or non-functioning pituitary adenoma. From the patient's perspective, the burden of disease is caused by the tumour itself and associated compression symptoms, interventions, hormone excess and deficiencies, systemic manifestations of these endocrine abnormalities and general psychosocial issues that can manifest in patients with a chronic condition. In this review, patient burden is classified according to classic endocrine syndromes, with burden at diagnosis and after long-term remission, and also within the framework of value-based health care and the conceptual model of wellbeing. The recently developed patient-reported outcome measurement tool that helps to evaluate burden of patients is also discussed.

ACROSTART: A retrospective study of the time to achieve hormonal control with lanreotide Autogel treatment in Spanish patients with acromegaly

OBJECTIVES

The ACROSTART study was intended to determine the time to achieve normalization of GH and IGF-I levels in responding patients with acromegaly administered different dosage regimens of lanreotide Autogel (Somatuline^® Autogel^®).

METHODS

From March 2013 to October 2013, clinical data from 57 patients from 17 Spanish hospitals with active acromegaly treated with lanreotide for ≥4 months who achieved hormonal control (GH levels <2.5ng/ml and/or normalized IGF-I levels in ≥2 measurements) were analyzed. The primary objective was to determine the time from start of lanreotide treatment to hormonal normalization.

RESULTS

Median patient age was 64 years, 21 patients were male, 39 patients had undergone surgery, and 14 patients had received radiotherapy. Median hormonal values at start of lanreotide treatment were: GH, 2.6ng/ml; IGF-I, 1.6×ULN. The most common starting dose of lanreotide was 120mg (29 patients). The main initial regimens were 60mg/4 weeks (n=13), 90mg/4 weeks (n=6), 120mg/4 weeks (n=13), 120mg/6 weeks (n=6), and 120mg/8 weeks (n=9). An initial treatment regimen with a long interval (≥6 weeks) was administered in 25 patients. Mean duration of lanreotide treatment was 68 months (7-205). Median time to achieve hormonal control was 4.9 months. Injections were managed without healthcare assistance in 13 patients. Median number of visits to endocrinologists until hormonal control was achieved was 3. Fifty-one patients were "satisfied"/"very satisfied" with treatment and 49 patients did not miss any dose.

CONCLUSIONS

Real-life treatment with lanreotide Autogel resulted in early hormonal control in responding patients, with high treatment adherence and satisfaction despite disparity in starting doses and dosing intervals.

Activation of Protein Kinase A Stimulates SUMOylation, Expression, and Transport Activity of Organic Anion Transporter 3

Organic anion transporter 3 (OAT3) plays a vital role in removing a broad variety of anionic drugs from kidney, thus avoiding their possible toxicity in the body. We earlier established that activation of protein kinase C (PKC) enhances OAT3 ubiquitination, which promotes OAT3 internalization from the cell plasma membrane to intracellular endosomes and consequent degradation. As a result, OAT3 expression and transport activity are reduced. In the current study, we discovered that protein kinase A (PKA) had an opposite effect to PKC on the regulation of OAT3. We showed that activation of PKA by Bt2-cAMP stimulated OAT3 transport activity, which was largely caused by an enhanced plasma membrane expression of the transporter, kinetically reflected as an augmented maximal transport velocity V_max without notable alteration in substrate-binding affinity K_m. Additionally, we showed that PKA activation accelerated the rate of OAT3 recycling from intracellular compartments to the plasma membrane and decelerated the rate of OAT3 degradation. We further showed that OAT3 is subjected to post-translational modification by SUMO-2 and SUMO-3 not by SUMO-1. PKA activation enhanced OAT3 SUMOylation, which was accompanied by a reduced OAT3 ubiquitination. Finally, insulin-like growth factor 1 significantly stimulated OAT3 transport activity and SUMOylation through PKA signaling pathway. In conclusion, this is the first demonstration that PKA stimulated OAT3 expression and transport activity by altering the trafficking kinetics of OAT3 possibly through the crosstalk between SUMOylation and ubiquitination. Our studies are consistent with a remote sensing and signaling model for transporters (Wu et al. in Mol Pharmacol. 79(5):795-805, 2011).

Targeting growth hormone function: strategies and therapeutic applications

Human growth hormone (GH) is a classical pituitary endocrine hormone that is essential for normal postnatal growth and has pleiotropic effects across multiple physiological systems. GH is also expressed in extrapituitary tissues and has localized autocrine/paracrine effects at these sites. In adults, hypersecretion of GH causes acromegaly, and strategies that block the release of GH or that inhibit GH receptor (GHR) activation are the primary forms of medical therapy for this disease. Overproduction of GH has also been linked to cancer and the microvascular complications that are associated with diabetes. However, studies to investigate the therapeutic potential of GHR antagonism in these diseases have been limited, most likely due to difficulty in accessing therapeutic tools to study the pharmacology of the receptor in vivo. This review will discuss current and emerging strategies for antagonizing GH function and the potential disease indications.

Emerging therapies are offering an expanded toolkit for combatting the effects of human growth hormone overproduction. Human growth hormone (GH) is a major driver of postnatal growth; however, systemic or localized overproduction is implicated in the aberrant growth disease acromegaly, cancer, and diabetes. In this review, researchers led by Jo Perry, from the University of Auckland, New Zealand, discuss strategies that either inhibit GH production, block its systemic receptor, or interrupt its downstream signaling pathways. The only licensed GH receptor blocker is pegvisomant, but therapies are in development that include long-acting protein and antibody-based blockers, and nucleotide complexes that degrade GHR production have also shown promise. Studies investigating GHR antagonism are limited, partly due to difficulty in accessing therapeutic tools which block GHR function, but overcoming these obstacles may yield advances in alleviating chronic disease.

Systemic Complications of Acromegaly and the Impact of the Current Treatment Landscape: An Update

Acromegaly is a chronic systemic disease with many complications and is associated with increased mortality when not adequately treated. Substantial advances in acromegaly treatment, as well as in the treatment of many of its complications, mainly diabetes mellitus, heart failure, and arterial hypertension, were achieved in the last decades. These developments allowed change in both prevalence and severity of some acromegaly complications and furthermore resulted in a reduction of mortality. Currently, mortality seems to be similar to the general population in adequately treated patients with acromegaly. In this review, we update the knowledge in complications of acromegaly and detail the effects of different acromegaly treatment options on these complications. Incidence of mortality, its correlation with GH (cumulative exposure vs last value), and IGF-I levels and the shift in the main cause of mortality in patients with acromegaly are also addressed.

The effectiveness of a therapist-oriented home rehabilitation program for a patient with acromegaly: A case study

BACKGROUND

Acromegaly causes numerous functional limitations that negatively impact patients' performance of activities of daily living (ADLs) and contribute to the deterioration of health-related quality of life (HRQoL). Thus, the purpose of the present case study was to evaluate the effect of therapist-oriented home rehabilitation (TOHR) for a patient with acromegaly.

CASE DESCRIPTION

We report the case of a 53-year-old man who was diagnosed with primary acromegaly 17 years ago. He complained of difficulties performing tasks that involved his hands, pain in the lower limbs, and fatigue when he climbed a few flights of stairs. Although he performed ADLs independently, he reported some difficulties or discomfort when performing them.

INTERVENTION AND OUTCOME

The patient underwent a booklet-guided physical exercise program that lasted two months (three times per week, 60 minutes per session). The activities included overall stretching, muscle strengthening, and endurance exercises, along with aerobic conditioning through functional circuit training. After two months of exercise, he reported improved HRQoL as assessed with the Acromegaly Quality of Life Questionnaire, with increases in quadriceps muscle strength and 6-min walking distance. However, none of these benefits remained when the patient was assessed after a 1-month washout period.

CONCLUSION

This study showed that patients with acromegaly may benefit markedly from TOHR, which could provide a novel therapeutic approach as an adjunct to hormone control therapy.