Mutations in Two Genes, USP48 and BRAF, Linked to Cushing’s Disease

Mutations in USP48 and BRAF genes contribute to the overproduction of adrenocorticotropin (ACTH) hormone by the pituitary gland and consequent development of Cushing’s disease, a study shows, linking these genes to the disease for a first time.

The study, “Identification of recurrent USP48 and BRAF mutations in Cushing’s disease,” published in the journal Nature Communications, also identified a possible treatment for patients with BRAF-related mutations.

Cushing’s disease is a condition characterized by excessive cortisol levels that, if left untreated, can lead to serious cardiovascular problems, infections, and mood disorders. It usually arises from benign pituitary tumors that produce too much of ACTH hormone, which in turn stimulates the adrenal glands to secrete cortisol.

It is still not clear why some people develop these tumors, but studies have pointed to mutations in the USP8 gene as a possible cause. They are present in 35%–62% of all tumor cases, and influence treatment response and long-term outcomes.

But major disease drivers in people whose tumors have no evidence of  USP8 mutations are unknown. Recognizing this gap, researchers in China examined tumor tissue samples from 22 patients with pituitary ademonas but a normal USP8 gene.

Their analysis revealed four genes that were recurrently mutated, including two — BRAF and USP48 — never before reported in this disease setting. Then, looking at 91 samples from patients, researchers found BRAF mutations in 17% of cases and USP48 mutations in 23% of patients.

These mutations were also found in patients with USP8-mutant pituitary tumors, but at a much lower rate — 5.1% for BRAF and 1.2% for USP48 mutations.

However, mutations in these two genes were not seen in patients with pituitary tumors producing other hormones, suggesting they are “unique genetic signatures of [ACTH-producing] adenomas,” the researchers wrote.

The team also found that BRAF and USP48 mutations activate signaling pathways that lead to the production of proopiomelanocortin (POMC), which is the precursor of ACTH.

“ACTH overproduction is a hallmark of Cushing’s disease and appears to be frequently induced by mutations in genes that tightly regulate POMC gene transcription in the pathogenesis of this disease,” investigators wrote.

Patients with BRAF and USP48 mutations had significantly higher levels of midnight plasma ACTH and midnight serum cortisol, compared to patients without these mutations. Tumor size, however, was similar among the two groups.

Interestingly, the team found that the BRAF inhibitor Zelboraf (vemurafenib) effectively reduced ACTH production in cells from ACTH-producing pituitary tumors. Zelboraf, marketed by Genentech, is approved in the U.S. and Europe to treat cancers with BRAF mutations, and findings suggest it may be a good therapeutic candidate for some people with Cushing’s disease.

“The mutational status of BRAFUSP8, and USP48 in corticotroph adenomas may be used in the future to characterize the molecular subtypes and guide targeted molecular therapy,” the researchers suggested.

From https://cushingsdiseasenews.com/2018/11/20/mutations-in-usp48-braf-genes-contribute-for-cushings-disease-study-finds/

Pituitary Tumors Affect Patients’ Ability to Work, Reduce Quality of Life

Pituitary tumor conditions, such as Cushing’s disease, have a substantial effect on patients’ work capabilities and health-related quality of life, researchers from The Netherlands reported.

The study, “Work disability and its determinants in patients with pituitary tumor-related disease,” was published in the journal Pituitary.

Pituitary tumors, like those that cause Cushing’s disease, have significant effects on a patient’s physical, mental, and social health, all of which influence their work status and health-related quality of life. However, the effects of the disease on work status is relatively under-investigated, investigators report.

Here, researchers evaluated the work disability among patients who were treated for pituitary tumors in an attempt to understand the impact of disease diagnosis and treatment on their social participation and ability to maintain a paying job.

In their study, researchers examined 241 patients (61% women) with a median age of 53 years. The majority (27%) had non-functioning pituitary tumors, which do not produce excess hormones, but patients with acromegaly, Cushing’s disease, prolactinomas, and Rathke’s cleft cyst also were included.

Participants were asked to complete questionnaires to evaluate their health-related quality of life and disease-specific impact on their work capabilities. Each participant completed a set of five questionnaires.

Participants also reported their hormonal status and demographic data, including gender, age, education, and marital status. Specific information, such as disease diagnosis, treatment, and tumor type was obtained from their medical records.

Work status and productivity were assessed using two surveys, the Short-Form-Health and Labour Questionnaire (SF-HLQ) and the work role functioning questionnaire 2.0 (WRFQ).

SF-HLQ was used to obtain information on the participants’ employment and their work attendance. Employment was either paid or unpaid. (Participation in household chores was considered not having a paid job.)

WRFQ is a 27-question survey that determines work disability regarding being able to meet the productivity, physical, emotional, social, and flexible demands. A higher score indicates low self-perceived work disability.

Disease-specific mood problems, social and sexual functioning issues, negative perceptions due to illness, physical and cognitive difficulties, were assessed using a 26-item survey called Leiden Bother and Needs for Support Questionnaire for pituitary patients(LBNQ-Pituitary).

Overall, 28% of patients did not have a paid job, but the rates increased to 47% among those with Cushing’s disease. Low education, hormonal deficits, and being single were identified as the most common determinants of not having a paid job among this population.

Further analysis revealed that more patients with Cushing’s disease and acromegaly had undergone radiotherapy. They also had more hormonal deficits than others with different tumor types.

Overall, patients with a paid job reported working a median of 36 hours in one week and 41% of those patients missed work an average of 27 days during the previous year. Health-related problems during work also were reported by 39% with a paid job.

Finally, health-related quality of life was determined using two questionnaires: SF-36 and EQ-5D. The physical, mental, and emotional well being was measured with SF-36, while ED-5D measured the health outcome based on the impact of pain, mobility, self-care, usual activities, discomfort, and anxiety or depression. In both SF-36 and EQ-5D, a higher score indicates a better health status.

Statistical analysis revealed that the quality of life was significantly higher in patients with a job. Overall, patients with a paid job reported better health status and higher quality of life than those without a paid job.

Although 40% of the patients reported being bothered by health-related problems in the past year, only 12% sought the help of an occupational physician, the researchers reported.

“Work disability among patients with a pituitary tumor is substantial,” investigators said.

“The determinants and difficulties at work found in this study could potentially be used for further research, and we advise healthcare professionals to take these results into consideration in the clinical guidance of patients,” they concluded.

From https://cushingsdiseasenews.com/

FDA Approves High-resolution MRI, Better at Spotting Pituitary Tumors in Cushing’s Patients

The U.S. Food and Drug Administration has approved the clinical use of a magnetic resonance imaging (MRI) scanner — the ultra-high-field 7T Terra MRI — with unprecedented resolution that allows for more reliable images of the brain.

The approach recently allowed the precise localization of a small tumor in the pituitary gland, which standard MRI had failed to spot, in a patient with Cushing’s disease.

So far, only one scanner of this kind exists in the U.S.. It was installed in February 2017 at the Mark and Mary Stevens Neuroimaging and Informatics Institute (INI) of the Keck School of Medicine, University of Southern California (USC).

The new scanner has an increased magnetic field strength of 7 Tesla, which is more than four times that of conventional MRI. This property greatly improves the instrument’s signal-to-noise ratio, dramatically increasing the spatial resolution and contrast of its images so that scientists can visualize the human living brain in high-definition and with unprecedented detail.

The 7T Terra is ideal for high-resolution neuroimaging, exploration of neurodegenerative diseases such as Alzheimer’s and Parkinson’s, and diagnosis and treatment of other brain diseases, a USC news story by Zara Greenbaum states.

Earlier this year, a report described the case of women with Cushing’s disease with a pituitary adenoma (slow-growing, benign tumor in the pituitary gland) that was possible to localize only with the new 7T MRI.

Based on laboratory analysis that revealed high levels of adrenocorticotropic hormone(ACTH) and cortisol, the doctors suspected a pituitary adenoma and recommended the patient for surgery. However, they ignored the precise location of the tumor, which failed to be detected by standard MRI scanners (1T and 3T).

    Two hours before surgery, the woman underwent a 7T MRI scan which finally identified with high precision the location of the adenoma, a very small tumor of 8 mm on the right side of the pituitary gland.

    “The 7T may save patients an invasive procedure. It also makes it easier for neurosurgeons to selectively remove a tumor without damaging surrounding areas,” said Gabriel Zada, MD, associate professor of neurological surgery at the Keck School.

    Since its arrival, the device has supported exploratory research into both healthy and diseased brains.

    Now the scanner’s advanced imaging technology can be used to help with diagnosis, treatment and monitoring of patients with neurological diseases, including Cushing’s disease.

    “This device, which has already made its mark as a powerful tool to advance research in the neurosciences, is now accessible to clinical populations in addition to researchers,” said Arthur W. Toga, PhD, provost professor and chair at the Keck School and director of the USC Stevens INI.

    “Clinicians across the university and beyond can now leverage all the benefits of increased spatial resolution to serve patients in need,” he said.

    Adapted from https://cushingsdiseasenews.com/2018/11/06/fda-oks-high-resolution-mri-better-spotting-pituitary-tumor-cushings/

    No Association Between Long-Term Gh Replacement, Comorbidities In Nonfunctioning Pituitary Adenoma

    Hammarstrand C, et al. Eur J Endocrinol. 2018;doi:10.1530/EJE-18-0370.

    Patients with growth hormone deficiency due to nonfunctioning pituitary adenoma experienced excessive morbidity due to cerebral infarction and sepsis regardless of whether they received long-term GH therapy, whereas treatment was associated with a normal incidence of type 2 diabetes, despite higher BMI and more severe hypopituitarism in treated patients, according to findings from an observational, registry-based study.

    “Although growth hormone replacement therapy is well-established and reverses most of the features associated with GH [deficiency], one of the safety concerns is the reduction in insulin sensitivity and the potential risk of developing type 2 diabetes mellitus,” Daniel S. Olsson, MSc, MD, PhD, professor at the Sahlgrenska Academy Institute of Medicine at the University of Gothenburg, Sweden, and colleagues wrote in the study background.

    Studies examining whether there is an association have produced mixed results, the researchers wrote, and it remains unknown to what extent GH deficiency — and GH therapy —contribute to the development of type 2 diabetes and other comorbidities, including cerebral infarction, malignant tumors, myocardial infarction or fractures.

    Olsson and colleagues analyzed data from 426 patients treated or followed for nonfunctioning pituitary adenoma between 1997 and 2011, selected from the Swedish National Patient Register. Researchers assessed information on tumor treatment, hormone therapy, antihypertensive medication, BMI and duration of GH therapy. For patients with type 2 diabetes, researchers assessed HbA1c values, insulin treatment, oral antidiabetes therapies and lipid-lowering therapies. Researchers followed the cohort through December 2014 or until death. Patients were stratified by use of GH therapy. Researchers calculated standardized incidence ratios (SIRs) based on the observed number of comorbidities among patients with nonfunctioning pituitary adenoma vs. the expected number of comorbidities in the background population.

    Within the cohort, 207 patients received GH therapy (145 men) and 219 did not (129 men). Median duration of GH therapy was 11.7 years; mean age at diagnosis was 56 years for treated patients and 65 years for untreated patients. Median follow-up time for treated and untreated patients was 12.2 years and 8.2 years, respectively.

    Incidence of cerebral infarction was increased for the whole cohort regardless of GH therapy status, with an SIR of 1.39 (95% CI, 1.03-1.84), and was most evident among 97 patients who underwent radiotherapy, in which 19 cerebral infarctions occurred vs. the expected number of 9.8 (P = .011).

    “The study showed an increased overall incidence of cerebral infarction in patients with [nonfunctioning pituitary adenoma] compared to the general population that was related to previous radiotherapy, but not to GH [replacement therapy],” the researchers wrote.

    Incidence of myocardial infarction was similar for treated and untreated patients, with SIRs of 1.18 (95% CI, 0.73-1.8) and 1.23 (95% CI, 0.82-1.78), respectively. Incidence of receiving medical treatment for hypertension was also similar between groups.

    In assessing incidence of type 2 diabetes, the researchers found that the SIR was higher among untreated patients (1.65; 95% CI, 1.06-2.46) vs. treated patients, who had an SIR similar to the background population (0.99; 95% CI, 0.55-1.63). Treated patients with type 2 diabetes had higher BMI vs. untreated patients with type 2 diabetes (P = .01), according to researchers, and glycemic status was similar among treated and untreated patients.

    The incidence of sepsis requiring hospitalization was also similar between treated and untreated patients, with rates for both groups close to double that of the background population (P < .001). Incidence of malignant tumors was not increased for treated or untreated patients when compared against the background population, according to the researchers. – by Regina Schaffer

    DisclosuresThe Gothenburg Growth Hormone Database is supported partly through unrestricted grants from Novo Nordisk, Pfizer and Sandoz. Olsson reports he has served as a consultant for Ipsen, Pfizer and Sandoz. Another author reports he has served as a consultant to AstraZeneca and Viropharma/Shire, and received lecture fees from Novo Nordisk, Otsuka and Pfizer.

    From https://www.healio.com/endocrinology/neuroendocrinology/news/in-the-journals/%7B0739a3a3-f592-4352-93f0-2ee5b5a89251%7D/no-association-between-long-term-gh-replacement-comorbidities-in-nonfunctioning-pituitary-adenoma

    New Phase 3 Data Further Support Recorlev’s Ability to Safely Lower Cortisol Levels in Cushing’s Patients

    Strongbridge Biopharma released additional positive results from a Phase 3 trial evaluating whether the company’s investigational therapy Recorlev (levoketoconazole) is safe and effective for people with endogenous Cushing’s syndrome.

    The latest results were presented in the scientific poster “Safety and Efficacy of Levoketoconazole in Cushing Syndrome:  Initial Results From the Phase 3 SONICS Study,\” at the 18th Annual Congress of the European NeuroEndocrine Association (ENEA), which took place in Wrocław, Poland, last month.

    The SONICS study (NCT01838551) was a multi-center, open-label Phase 3 trial evaluating Recorlev’s safety and effectiveness in 94 patients with endogenous Cushing’s syndrome.

    The trial consisted of three parts: a dose-escalation phase to determine the appropriate Recorlev dose that achieved normalization of cortisol levels; a maintenance phase in which patients received the established dose for six months; and a final extended phase, in which patients were treated with Recorlev for an additional six months, with the possibility of dose adjustments.

    Its primary goal was a reduction in the levels of cortisol in the patients’ urine after six months of maintenance treatment, without any dose increase during that period. Among secondary goals was a reduction in the characteristically high risk of cardiovascular disease in these people, through the assessment of multiple cardiovascular risk markers.

    Strongbridge announced top-line results of the SONICS study in August, which showed that the trial had reached its primary and secondary goals. It concluded last month.

    After six months of maintenance therapy, Recorlev successfully lowered to normal the levels of cortisol in 30% of patients without a dose increase. It also led to statistically and clinically significant reductions in cardiovascular risk biomarkers, including blood sugar, cholesterol levels, body weight, and body mass index.

    Maria Fleseriu, MD, director of the Oregon Health Sciences University Northwest Pituitary Center, presented additional and detailed results of SONICS at the congress.

    Additional analyses showed that among the 77 patients who completed the dose-escalation phase and entered the study’s maintenance phase, 81% had their cortisol levels normalized.

    At the end of the six months of maintenance treatment, 29 (53%) of the 55 patients who had their cortisol levels assessed at the beginning of the study and at the end of the maintenance phase had achieved normalization of cortisol levels, regardless of dose increase.

    Among all patients who completed maintenance treatment (including patients with some missing data) and regardless of dose increase, 38% had achieved normalization of cortisol levels and 48% recorded a 50% or more decrease or normalization.

    The results also highlighted that Recorlev substantially reduced patients’ cortisol levels regardless of their levels at the study’s beginning (which were on average about five-fold higher than the upper limit of normal). In those patients with the highest levels of cortisol in their urine, Recorlev led to a median reduction of more than 80%.

    As previously reported, Recorlev was found to be generally well-tolerated, with no new safety concerns, and only 12 participants (12.8%) stopped treatment due to adverse events.

    Ten patients had three- or five-fold increased levels of alanine aminotransferase — a liver enzyme used to assess liver damage — which were fully resolved without further complications. These liver-related adverse events “were all noted in the first 60 days, thus suggesting a timeline interval for monitoring,” Fleseriu said in a press release.

    “We continue to be encouraged by the positive efficacy results of SONICS and the overall benefit-to-risk profile of Recorlev and look forward to sharing additional planned analyses from the study in the near future,” said Fredric Cohen, Strongbridge’s chief medical officer.

    From https://cushingsdiseasenews.com/2018/11/01/new-data-from-phase-3-trial-supports-recorlev-ability-to-safely-treat-cushings-syndrome/

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