New discoveries offer possible Cushing’s disease cure

LOS ANGELES — More than a century has passed since the neurosurgeon and pathologist Harvey Cushing first discovered the disease that would eventually bear his name, but only recently have several key discoveries offered patients with the condition real hope for a cure, according to a speaker here.

There are several challenges clinicians confront in the diagnosis and treatment of Cushing’s disease, Shlomo Melmed, MB, ChB, FRCP, MACP, dean, executive vice president and professor of medicine at Cedars-Sinai Medical Center in Los Angeles, said during a plenary presentation. Patients who present with Cushing’s disease typically have depression, impaired mental function and hypertension and are at high risk for stroke, myocardial infarction, thrombosis, dyslipidemia and other metabolic disorders, Melmed said. Available therapies, which range from surgery and radiation to the somatostatin analogue pasireotide (Signifor LAR, Novartis), are often followed by disease recurrence. Cushing’s disease is fatal without treatment; the median survival if uncontrolled is about 4.5 years, Melmed said.

“This truly is a metabolic, malignant disorder,” Melmed said. “The life expectancy today in patients who are not controlled is apparently no different from 1930.”

The outlook for Cushing’s disease is now beginning to change, Melmed said. New targets are emerging for treatment, and newly discovered molecules show promise in reducing the secretion of adrenocorticotropic hormone (ACTH) and pituitary tumor size.

“Now, we are seeing the glimmers of opportunity and optimism, that we can identify specific tumor drivers — SST5, [epidermal growth factor] receptor, cyclin inhibitors — and we can start thinking about personalized, precision treatment for these patients with a higher degree of efficacy and optimism than we could have even a year or 2 ago,” Melmed said. “This will be an opportunity for us to broaden the horizons of our investigations into this debilitating disorder.”

Challenges in diagnosis, treatment

Overall, about 10% of the U.S. population harbors a pituitary adenoma, the most common type of pituitary disorder, although the average size is only about 6 mm and 40% of them are not visible, Melmed said. In patients with Cushing’s disease, surgery is effective in only about 60% to 70% of patients for initial remission, and overall, there is about a 60% chance of recurrence depending on the surgery center, Melmed said. Radiation typically leads to hypopituitarism, whereas surgical or biochemical adrenalectomy is associated with adverse effects and morbidity. Additionally, the clinical features of hypercortisolemia overlap with many common illnesses, such as obesity, hypertension and type 2 diabetes.

“There are thousands of those patients for every patient with Cushing’s disease who we will encounter,” Melmed said.

The challenge for the treating clinician, Melmed said, is to normalize cortisol and ACTH with minimal morbidity, to resect the tumor mass or control tumor growth, preserve pituitary function, improve quality of life and achieve long-term control without recurrence.

“This is a difficult challenge to meet for all of us,” Melmed said.

Available options

Pituitary surgery is typically the first-line option offered to patients with Cushing’s disease, Melmed said, and there are several advantages, including rapid initial remission, a one-time cost and potentially curing the disease. However, there are several disadvantages with surgery; patients undergoing surgery are at risk for postoperative venous thromboembolism, persistent hypersecretion of ACTH, adenoma persistence or recurrence, and surgical complications.

Second-line options are repeat surgery, radiation, adrenalectomy or medical therapy, each with its own sets of pros and cons, Melmed said.

“The reality of Cushing’s disease — these patients undergo first surgery and then recur, second surgery and then recur, then maybe radiation and then recur, and then they develop a chronic illness, and this chronic illness is what leads to their demise,” Melmed said. “Medical therapy is appropriate at every step of the spectrum.”

Zebrafish clues

Searching for new options, Melmed and colleagues introduced a pituitary tumor transforming gene discovered in his lab into zebrafish, which caused the fish to develop the hallmark features of Cushing’s disease: high cortisol levels, diabetes and cardiovascular disease. In the fish models, researchers observed that cyclin E activity, which drives the production of ACTH, was high.

Melmed and colleagues then screened zebrafish larvae in a search for cyclin E inhibitors to derive a therapeutic molecule and discovered R-roscovitine, shown to repress the expression of proopiomelanocortin (POMC), the pituitary precursor of ACTH.

In fish, mouse and in vitro human cell models, treatment with R-roscovitine was associated with suppressed corticotroph tumor signaling and blocked ACTH production, Melmed said.

“Furthermore, we asked whether or not roscovitine would actually block transcription of the POMC gene,” Melmed said. “It does. We had this molecule (that) suppressed cyclin E and also blocks transcription of POMC leading to blocked production of ACTH.”

In a small, open-label, proof-of-principal study, four patients with Cushing’s disease who received roscovitine for 4 weeks developed normalized urinary free cortisol, Melmed said.

Currently, the FDA Office of Orphan Products Development is funding a multicenter, phase 2, open-label clinical trial that will evaluate the safety and efficacy of two of three potential doses of oral roscovitine (seliciclib) in patients with newly diagnosed, persistent or recurrent Cushing disease. Up to 29 participants will be treated with up to 800 mg per day of oral seliciclib for 4 days each week for 4 weeks and enrolled in sequential cohorts based on efficacy outcomes.

“Given the rarity of the disorder, it will probably take us 2 to 3 years to recruit patients to give us a robust answer,” Melmed said. “This zebrafish model was published in 2011, and we are now in 2019. It has taken us 8 years from publication of the data to, today, going into humans with Cushing’s. Hopefully, this will light the pathway for a phase 2 trial.”

 Offering optimism’

Practitioners face a unique paradigm when treating patients with Cushing’s disease, Melmed said. Available first- and second-line therapy options often are not a cure for many patients, who develop multimorbidity and report a low quality of life.

“Then, we are kept in this difficult cycle of what to do next and, eventually, running out of options,” Melmed said. “Now, we can look at novel, targeted molecules and add those to our armamentarium and at least offer our patients the opportunity to participate in trials, or at least offer the optimism that, over the coming years, there will be a light at the end of the tunnel for their disorder.”

Melmed compared the work to Lucas Cranach’s Fons Juventutis (The Fountain of Youth). The painting, completed in 1446, shows sick people brought by horse-drawn ambulance to a pool of water, only to emerge happy and healthy.

“He was imagining this ‘elixir of youth’ (that) we could offer patients who are very ill and, in fact, that is what we as endocrinologists do,” Melmed said. “We offer our patients these elixirs. These Cushing’s patients are extremely ill. We are trying with all of our molecular work and our understanding of pathogenesis and signaling to create this pool of water for them, where they can emerge with at least an improved quality of life and, hopefully, a normalized mortality. That is our challenge.” – by Regina Schaffer

Reference:

Melmed S. From zebrafish to humans: translating discoveries for the treatment of Cushing’s disease. Presented at: AACE Annual Scientific and Clinical Congress; April 24-28, 2019; Los Angeles.

Disclosure: Melmed reports no relevant financial disclosures.

 

From https://www.healio.com/endocrinology/neuroendocrinology/news/online/%7B585002ad-640f-49e5-8d62-d1853154d7e2%7D/new-discoveries-offer-possible-cushings-disease-cure

Blood Lipid Levels Linked to High Blood Pressure in Cushing’s Disease Patients

High lipid levels in the blood may lead to elevated blood pressure in patients with Cushing’s disease, a Chinese study shows.

The study, “Evaluation of Lipid Profile and Its Relationship with Blood Pressure in Patients with Cushing’s Disease,” appeared in the journal Endocrine Connections.

Patients with Cushing’s disease often have chronic hypertension, or high blood pressure, a condition that puts them at risk for cardiovascular disease. While the mechanisms of Cushing’s-related high blood pressure are not fully understood, researchers believe that high levels of cortisol lead to chronic hypertension through increased cardiac output, vascular resistance, and reactivity to blood vessel constrictors.

In children and adults with Cushing’s syndrome, the relationship between increased cortisol levels and higher blood pressure has also been reported. Patients with Cushing’s syndrome may remain hypertensive even after surgery to lower their cortisol levels, suggesting their hypertension is caused by changes in blood vessels.

Studies have shown that Cushing’s patients have certain changes, such as increased wall thickness, in small arteries. The renin-angiotensin system, which can be activated by glucocorticoids like cortisol, is a possible factor contributing to vascular changes by increasing the uptake of LDL-cholesterol (LDL-C) — the “bad” cholesterol — in vascular cells.

Prior research showed that lowering cholesterol levels could benefit patients with hypertension and normal lipid levels by decreasing the stiffness of large arteries. However, the link between blood lipids and hypertension in Cushing’s disease patients is largely unexplored.

The study included 84 patients (70 women) referred to a hospital in China for evaluation and diagnosis of Cushing’s disease. For each patient, researchers measured body mass index, blood pressure, lipid profile, and several other biomarkers of disease.

Patients with high LDL-cholesterol had higher body mass index, blood pressure, cholesterol, triglycerides, and apolipoproteinB (apoB), a potential indicator of atherosclerosis and cardiovascular disease.

Data further revealed an association between blood pressure and lipid profile, including cholesterol, triglycerides, apoB and LDL-c. “The results strongly suggested that CHO (cholesterol), LDL-c and apoB might predict hypertension more precisely in [Cushing’s disease],” the scientists wrote.

They further add that high cholesterol, LDL-cholesterol, and apoB might be contributing to high blood pressure by increasing vessel stiffness.

Additional analysis showed that patients with higher levels of “bad” cholesterol — 3.37 mmol/L or higher — had higher blood pressure. This finding remained true, even when patients were receiving statins to lower their cholesterol levels.

No association was found between blood pressure and plasma cortisol, UFC, adrenocorticotropic hormone, or glucose levels in Cushing’s disease patients.

These findings raise some questions on whether lipid-lowering treatment for high blood pressure and cardiovascular disease would be beneficial for Cushing’s disease patients. Further studies addressing this question are warranted.

Adapted from https://cushingsdiseasenews.com/2018/04/24/blood-pressure-linked-lipid-levels-cushings-disease-study/

Health Care Expenditure Burden High in Adrenal Insufficiency

Patients with adrenal insufficiency may accrue substantial health care costs and have more hospital stays and outpatient visits compared with healthy controls, according to findings published in the Journal of the Endocrine Society.

Candace Gunnarsson, PhD, vice president of health economics and outcomes research at CTI Clinical Trial and Consulting in Cincinnati, and colleagues evaluated data from a U.S.-based payer database on 10,383 patients with adrenal insufficiency to determine the estimated annual health care burden among them.

Participants were divided into groups based on their type of adrenal insufficiency: primary adrenal insufficiency (n = 1,014), adrenal insufficiency secondary to pituitary disease (n = 8,818) or congenital adrenal hyperplasia (n = 551). A group of matched controls was also evaluated for comparison.

Total annual health care expenditures were significantly higher in the primary adrenal insufficiency group ($18,624 vs. $4,320), adrenal insufficiency secondary to pituitary disease group ($32,218 vs. $6,956) and the congenital adrenal hyperplasia group ($7,677 vs. $4,203) compared with controls. The adrenal insufficiency secondary to pituitary disease group had the highest health care expenditure estimated with an incremental health care burden of $25,262, followed by the primary adrenal insufficiency group ($14,304) and the congenital adrenal hyperplasia group ($3,474).

Compared with controls, participants with adrenal insufficiency spent eight to 10 times more days in the hospital and had up to twice as many outpatient visits per year.

“When comparing [adrenal insufficiency] patients within each cohort based on their drug regimen, patients receiving prednisone therapy vs. hydrocortisone therapy had significantly higher total annual expenditures in the [primary adrenal insufficiency] and [congenital adrenal hyperplasia] and significantly lower total expenditures in the [pituitary disease] cohort,” the researchers wrote. “Patients taking only hydrocortisone and meeting the threshold of 50% adherence were found to have lower expenditures when medication adherence was 75% or higher.” – by Amber Cox

Disclosure: Gunnarsson reports being an employee of CTI Clinical Trial and Consulting. Please see the full study for a list of all other authors’ relevant financial disclosures.

From http://www.healio.com/endocrinology/adrenal/news/in-the-journals/%7B8f92bd0c-0c72-4902-beb5-663c356a61cb%7D/health-care-expenditure-burden-high-in-adrenal-insufficiency

Lower health-related quality of life observed in patients with Addison’s disease, Cushing’s syndrome

Patients with hypothalamic-pituitary-adrenal axis dysregulations report health-related quality of life that is far lower than that of the general population, according to findings of a prospective study.

“In most centers, both patients with adrenal deficiency and patients with Cushing’s syndrome are managed by the same team,” Charlotte DeBucy, of the Center for Rare Adrenal Diseases at Cochin Hospital in Paris, and colleagues wrote. “Despite the usual perception that both types of diseases alter quality of life, few studies have similarly investigated the impact of cortisol dysregulations on [health-related quality of life]. Such studies are important, however, to identify meaningful differences that would be important to consider to improve management and outcome.”

De Bucy and colleagues analyzed data from 343 patients with Addison’s disease or Cushing’s syndrome followed in routine practice at a single center in France between September 2007 and April 2014 (78% women; mean age, 48 years; mean length of time since diagnosis, 7.8 years; 61% married). All participants completed the short-form health survey (SF-36), a survey of health-related quality-of-life measures and the 12-item general health questionnaire (GHQ-12), a measure of psychological well-being or distress. Questionnaires were completed at baseline and at 6, 12, 24 and 36 months. Patients with Cushing’s syndrome were also assessed for cortisol status at baseline and at follow-up evaluations.

Within the cohort, 206 had Cushing’s syndrome of pituitary origin, 91 had Cushing’s syndrome of adrenal origin and 46 patients had Addison’s disease; 16% were included in the study before any treatment was initiated.

Researchers found that mean standard deviation scores for psychological and physical dimensions of the SF-36 were “well below” those of the general population, but diagnosis, cortisol status and time since treatment initiation all influenced individual scores. Cushing’s syndrome of pituitary origin was associated with worse health-related quality of life, especially for physical functioning, social functioning and mental health. In Cushing’s syndrome, health-related quality of life was generally worse during periods of hypercortisolism, but scores for these patients were lower than those of patients with Addison’s disease even during periods of hypocortisolism or eucortisolism, according to the researchers.

“The differences were particularly large for physical functioning and role-physical subscales,” the researchers wrote.

They also found that mental health scores for patients with Cushing’s syndrome decreased during periods of hypocortisolism, whereas other adrenal conditions were associated with higher mental health scores.

More than half of patients, regardless of diagnosis and cortisol status, had psychological distress requiring attention, according to the GHQ-12 survey.

“Our findings are important for clinical practice,” the researchers wrote. “The consequences of cortisol dysregulation on [health-related quality of life] should be considered in the management of adrenal insufficiency and even more (in) Cushing’s syndrome patients, and these consequences can be long term, affecting apparently cured patients. Early information on these consequences might be helpful for patients who often perceive a poor quality of life as the result of inadequate disease control or treatment. Even if this possibility exists, knowing that adrenal diseases have long-lasting effects on [health-related quality of life] may be helpful for patients to cope with them.” – by Regina Schaffer

Disclosure: L’association Surrénales supported this study. The researchers report no relevant financial disclosures.

From http://www.healio.com/endocrinology/adrenal/news/in-the-journals/%7B842655ce-e710-4476-a3c2-2909b06434ed%7D/lower-health-related-quality-of-life-observed-in-patients-with-addisons-disease-cushings-syndrome

Fluorescent Metabolite Might Help Surgeons Remove Pituitary Tumors

The resection of microadenomas — small, benign tumors in the pituitary gland underlying Cushing’s disease — could be aided by a fluorescent marker that is naturally produced by the tumor, a new study shows.

The findings were presented recently at the 2018 George Washington Research Days in a poster titled, “Enhanced 5-ALA Induced Fluorescence in Hormone Secreting Pituitary Adenomas.

Cushing’s disease is characterized by high cortisol levels that cause debilitating physical, mental, and hormonal symptoms. The excess cortisol is caused by tiny benign tumors in the pituitary gland, called microadenomas, with a size of less than 10 millimeters.

On account of their small size, these microadenomas pose imaging challenges to physicians. Up to 40 percent of microadenomas remain undetected in the gold-standard magnetic resonance imaging (MRI).

Pituitary adenomas, however, have a characteristic that distinguishes them from the surrounding healthy tissue. They process (metabolize) a natural haemoglobin metabolite, called 5-aminolevulinic acid (5-ALA), into protoporphyrin IX (PpIX) at much higher rates — up to 20 to 50 times higher — than normal tissues.

Importantly, PpIX emits red fluorescence when excited with blue light.

This means that exogenous 5-ALA is taken up by the adenoma cells and rapidly metabolized into the fluorescent metabolite, PpIX, which may establish its use for fluorescence-guided resection of pituitary adenomas.

To test this, researchers incubated human-derived corticotropinoma, as well as the adjacent normal gland cells with 5-ALA. They did the same with mouse model normal pituitary cells and a mouse model pituitary tumor cell line, called AtT20.

They then analyzed the cells’ fluorescence profile by microscopy and with a technique called flow cytometry.

The analysis showed that compared to normal pituitary tissue, human-derived adenomatous cells had a significant increase of tenfold in 5-ALA-induced PpIX fluorescence intensity.

Similarly, mouse pituitary tumor cells (AtT20 cell line) fluoresced seven times more intensely than normal murine pituitary tissue.

The microscopy analysis revealed that the 5-ALA localized in subcellular organelles called mitochondria.

On June 6, 2017, the U.S. Food and Drug Administration approved the use of 5-ALA (under the brand name Gleolan) as an optical imaging agent for patients with gliomas (brain tumors), as an add-on compound to assist surgeons in identifying the malignant tissue during surgery.

Now, these findings suggest that 5-ALA also may be used for fluorescence-guided surgery of microadenomas in Cushing’s disease.

“The supraphysiological levels of glucocorticoids, as seen in CD [Cushing’s disease], may enhance the 5-ALA fluorescence in corticotropinomas,” researchers wrote.

From https://cushingsdiseasenews.com/2018/04/13/fluorescent-metabolite-might-help-surgeons-removepituitary-tumors/