Treatment for Rare Cancer May Help Cushing’s Patients

The cancer medicine bexarotene may hold promise for treating Cushing’s disease, a study suggests.

The study, “Targeting the TR4 nuclear receptor with antagonist bexarotene can suppress the proopiomelanocortin signalling in AtT‐20 cells,” was published in the Journal of Cellular and Molecular Medicine.

Cushing’s disease is caused by a tumor on the pituitary gland, leading this gland to produce too much adrenocorticotropic hormone (ACTH). Excess ACTH causes the adrenal glands to release too much of the stress hormone cortisol; abnormally high cortisol levels are primarily responsible for the symptoms of Cushing’s.

Typically, first-line treatment is surgical removal of the pituitary tumor. But surgery, while effective in the majority of cases, does not help all. Additional treatment with medications or radiation therapy (radiotherapy) works for some, but not others, and these treatments often have substantial side effects.

“Thus, the development of new drugs for CD [Cushing’s disease] treatment is extremely urgent especially for patients who have low tolerance for surgery and radiotherapy,” the researchers wrote.

Recent research has shown that a protein called testicular receptor 4 (TR4) helps to drive ACTH production in pituitary cancers. Thus, blocking the activity of TR4 could be therapeutic in Cushing’s disease.

Researchers conducted computer simulations to screen for compounds that could block TR4. This revealed bexarotene as a potential inhibitor. Further biochemical tests confirmed that bexarotene could bind to, and block the activity of, TR4.

Bexarotene is a type of medication called a retinoid. It is approved to treat cutaneous T-cell lymphoma, a rare cancer that affects the skin, and available under the brand name Targretin.

When pituitary cancer cells in dishes were treated with bexarotene, the cells’ growth was impaired, and apoptosis (a type of programmed cell death) was triggered. Bexarotene treatment also reduced the secretion of ACTH from these cells.

In mice with ACTH-secreting pituitary tumors, bexarotene’s use significantly reduced tumor size, and lowered levels of ACTH and cortisol. Cushing’s-like symptoms also eased; for example, bexarotene treatment reduced the accumulation of fat around the abdomen in these mice.

Additional cellular experiments suggested that bexarotene specifically works on TR4 by changing the location of the protein. Normally, TR4 is present in the nucleus — the cellular compartment that houses DNA — where it helps to control the production of ACTH.

But with bexarotene treatment, TR4 tended to go outside of the nucleus, leading to lower ACTH production. The researchers noted that other mechanisms may also be involved in the observed effects of bexarotene.

“In summary, our work demonstrates that bexarotene is a potential inhibitor for TR4. Importantly, bexarotene may represent a new drug candidate to treat CD,” the researchers concluded.

Scientists Discover Biological Reason Why Women Are More Likely to Develop Adrenal Disorders

Scientists have discovered a potential biological reason why women are more likely to develop adrenal disorders, including cancer. According to the researchers, the answer could lie in the increased turnover of hormone-producing cells found in the adrenal glands of females.

The adrenal gland is a hormone producing organ that sits on top of the kidneys. The outer part, or cortex, is responsible for the production of several hormones, including the stress-related hormone cortisol and the blood pressure controlling aldosterone. Adrenal cancer is relatively rare but occurs approximately three times more in women than in men. The cellular basis for this difference has not been investigated in detail but uncovering it might lead to sex-specific treatments and has huge implications for many areas of research.

Dr Andreas Schedl, from INSERM, France, who led the study said:

To our surprise we found that adrenal cells in female mice show a much more rapid turnover compared to males, which we could trace back to a different behaviour of adrenal stem cells between the two sexes. Furthermore, we could show that the observed differences are due to hormones that are produced by testes that suppress cell division, thus slowing down renewal in the male adrenal.”

The scientists studied the adrenal cortex of male and female adult mice and found that female mice replace their entire set of hormone-producing cells within 3 months, while it takes male mice an entire 9 months. Using different techniques to label cells within the adrenal cortex, they established that females not only have a higher proliferation rate of cells, but also recruit stem cells from a different part of the adrenal gland.

The research has wide reaching implications, as it demonstrates the basic mechanism underlying the increased turnover of cells within the adrenal gland, providing a possible explanation for the increased incidence of adrenal disorders in women.

Dr Schedl explained: “It is early days and many more experiments will need to be performed before our research can directly benefit patients. However, we believe that our study teaches a number of important lessons that are of immediate relevance to scientists, pharmacologists and clinicians.”

This research might lead to sex-specific treatment options for diseases like adrenal cancer and, according to Dr Schedl, could have implications on a far wider field of disorders: “Importantly, while our study concentrated on the adrenals, we are convinced that similar differences may also be found in other organ systems.”

Dr Helen Rippon, Chief Executive of the charity Worldwide Cancer Research, whose supporters helped fund the study, said: “Sex differences are not necessarily the first thing that comes to mind when thinking about cancer research or treatments. But this study has shown that it is crucial to consider potential differences between male and female when trying to understand the basis of cancer biology. Most importantly, these findings could have implications for treatment options further down the line and highlight the importance of early-stage, discovery research. We are delighted to fund this kind of research, as we believe that these innovative approaches are ultimately going to lead to a world where no life is cut short by cancer.”

Worldwide Cancer Research, La Ligue Contre le Cancer and the ANR supported this research. The research was published in Cell Stem Cell.

Source:

Worldwide Cancer Research

Journal reference:

Grabek, A. et al. (2019) The Adult Adrenal Cortex Undergoes Rapid Tissue Renewal in a Sex-Specific MannerCell Stem Celldoi.org/10.1016/j.stem.2019.04.012.

From https://www.news-medical.net/news/20190522/Scientists-discover-biological-reason-why-women-are-more-likely-to-develop-adrenal-disorders.aspx

Metastatic Pituitary Carcinoma Successfully Treated with Radiation, Chemo.

A man with Cushing’s disease — caused by an adrenocorticotrophic hormone (ACTH)-secreting pituitary adenoma — who later developed metastases in the central nervous system without Cushing’s recurrence, was successfully treated over eight years with radiation and chemotherapy, according to a case report.

The report, “Long-term survival following transformation of an adrenocorticotropic hormone secreting pituitary macroadenoma to a silent corticotroph pituitary carcinoma: Case report,” was published in the journal World Neurosurgery.

Pituitary carcinomas make up only 0.1-0.2% of all pituitary tumors and are characterized by a primary pituitary tumor that metastasizes into cranial, spinal, or systemic locations. Fewer than 200 cases have been reported in the literature.

Most of these carcinomas secrete hormones, with ACTH being the most common. Though the majority of ACTH-secreting carcinomas present with Cushing’s disease, about one-third do not show symptoms of the condition and have normal serum cortisol and ACTH levels. These are called silent corticotroph adenomas and are considered more aggressive.

A research team at the University of Alabama at Birmingham presented the case of a 51-year-old Caucasian man with ACTH-dependent Cushing’s disease. He had undergone an incomplete transsphenoidal (through the nose) resection of an ACTH-secreting pituitary macroadenoma – larger than 10 mm in size – and radiation therapy the year before.

At referral in August 1997, the patient had persistent high cortisol levels and partial hypopituitarism, or pituitary insufficiency. He exhibited Cushing’s symptoms, including facial reddening, moon facies, weight gain above the collarbone, “buffalo hump,” and abdominal stretch marks.

About two years later, the man was weaned off ketoconazole — a medication used to lower cortisol levels — and his cortisol levels had been effectively reduced. He also had no physical manifestations of Cushing’s apart from facial reddening.

In May 2010, the patient reported two episodes of partial seizures, describing two spells of right arm tingling, followed by impaired peripheral vision. Imaging showed a 2.1-by-1-cm mass with an associated cyst within the brain’s right posterior temporal lobe, as well as a 1.8-by-1.2-cm mass at the cervicomedullary junction, which is the region where the brainstem continues as the spinal cord. His right temporal cystic mass was then removed by craniotomy.

A histopathologic analysis was consistent with pituitary carcinoma. Cell morphology was generally similar to the primary pituitary tumor, but cell proliferation was higher. Physical exams showed no recurrence of Cushing’s disease and 24-hour free urinary cortisol was within the normal range.

His cervicomedullary metastasis was treated with radiation therapy in July 2010. He took the oral chemotherapy temozolomide until August 2011, and Avastin (bevacizumab, by Genentech) was administered from September 2010 to November 2012.

At present, the patient continues to undergo annual imaging and laboratory draws. He receives treatment with hydrocortisone, levothyroxine — synthetic thyroid hormone — and testosterone replacement with androgel.

His most recent exam showed no progression over eight years of a small residual right temporal cyst, a residual mass along the pituitary stalk — the connection between the hypothalamus and the pituitary gland — and a small residual mass at the cervicomedullary junction. Lab results continue to show no Cushing’s recurrence.

“Our case is the first to document a patient who initially presented with an endocrinologically active ACTH secreting pituitary adenoma and Cushing’s disease who later developed cranial and spinal metastases without recurrence of Cushing’s disease and transformation to a silent corticotroph pituitary carcinoma,” the scientists wrote.

They added that the report is also the first documenting “8 years of progression-free survival in a patient with pituitary carcinoma treated with radiotherapy, [temozolomide] and bevacizumab.”

Adapted from https://cushingsdiseasenews.com/2019/01/03/successful-treatment-pituitary-carcinoma-radiation-chemo-case-report/

Rare Malignant Tumor of Adrenal Gland Led to Cushing’s, Girl’s Death

While adrenocortical carcinoma — a malignant tumor of the adrenal gland — appears only rarely in children, the tumor may cause secondary Cushing’s syndrome in these patients, a new case report shows.

Early diagnosis of the causes of Cushing’s syndrome could improve the prognosis of these children, researchers say.

The study, “Cushing Syndrome Revealing an Adrenocortical Carcinoma,” was published in the Open Journal of Pediatrics.

Adrenocortical carcinoma is a malignant tumor that develops in the cortex of the adrenal gland. It usually is identified by increased amounts of hormones that are produced by the adrenal glands, like cortisol.

This tumor type is very rare in children, representing fewer than two in every 1,000 pediatric tumors.

Researchers at the University Hospital Center Souro Sanou, in Burquina Faso (West Africa), described the case of a 10-year-old girl who developed this rare cancer.

The patient’s first symptoms were loss of consciousness and recurrent seizures without fever. The patient also had experienced excessive weight gain in the preceding months. At admission she was in a light state of coma and showed obesity in the face and trunk.

An initial analysis of blood, urine, and cerebrospinal fluid failed to detect any alterations, with no diabetes, kidney damage, or infection identified. And, even though no lesions or alteration were seen in the pituitary gland region, brain swelling was detected.

While in the hospital, the patient’s condition continued to deteriorate. She developed fever and difficulty speaking, while showing persistent seizures.

In the absence of a diagnosis, physicians focused on the safeguard of major vital function, control of seizures, and administration of large-spectrum antibiotics. Her condition improved slightly, regaining consciousness and control of seizures.

One month later, however, the patient developed symptoms that are commonly associated with increased levels of cortisol and male sex hormones, including obesity and early development of pubic hair.

After confirming high cortisol levels, physicians examined the patient’s abdominal region,  which revealed a tumor in the left adrenal gland.

The patient received a ketoconazole treatment and a surgery to remove the tumor was planned. But her condition worsened, with development of malignant hypertension and convulsive illness, which led to her death before the tumor was removed.

“The delay in the diagnosis and the insufficiency of the therapeutic means darken the prognosis in our context,” the researchers wrote.

“[Adrenocortical carcinoma] diagnosis should be considered in presence of virilization and early signs of puberty,” the researchers suggested. “Early diagnosis and multidisciplinary management of adrenocortical carcinoma could improve the prognosis in children.”

From https://cushingsdiseasenews.com/2018/05/04/rare-malignant-tumor-adrenal-gland-caused-cushings-case-report/

Rare Nasal Cancer May Have Caused Cushing’s Syndrome

A very rare case of Cushing’s syndrome developing as a result of a large and also rare cancer of the nasal sinuses gives insights into how to screen and treat such an anomaly, of which fewer than 25 cases have been reported in literature.

Paraneoplastic esthesioneuroblastoma (ENB), a very rare type of nasal tumor, may sometimes produce excess adrenocorticotrophic hormone (ACTH), leading to symptoms of Cushing’s syndrome, according to a recent case report that describes a case of ACTH-secreting ENB. The report aims to demonstrate the importance of recognizing its pathophysiology and treatment.

The case report, “A Case of Cushing’s Syndrome due to Ectopic Adrenocorticotropic Hormone Secretion from Esthesioneuroblastoma with Long Term Follow-Up after Resection,” was published in the journal Case Reports in Endocrinology.

It describes a 52-year-old Caucasian male who had a history of high blood pressure, severe weakness, abnormal production of urine, extreme thirstiness, and confusion.

He was scheduled to undergo surgery for a 7-centimeter skull base mass; the surgery was postponed due to severe high serum potassium concentrations and abnormally high pH levels. His plasma ACTH levels also were elevated and Cushing’s syndrome was suspected. Since imaging of the chest, abdomen, and pelvis did not show any ectopic (abnormal) sources of ACTH, the ENB was suspected to be the source.

Surgery was performed to remove the tumor, which was later found to be secreting ACTH. Consequently, following the procedure, his ACTH levels dropped to normal (below detection limit) and he did not need medication to normalize serum potassium levels. He then underwent subsequent chemoradiation and has shown no sign of recurrence 30 months after the operation, which is considered to be one of the longest follow-up periods for such a case.

Researchers declared it “a case of olfactory neuroblastoma with ectopic ACTH secretion that was treated with resection and adjuvant chemoradiation.”

“Given the paucity of this diagnosis, little is known about how best to treat these patients and how best to screen for complications such as adrenal insufficiency and follow-up,” they wrote. “Our case adds more data for better understanding of this disease.”

From https://cushingsdiseasenews.com/2018/04/03/rare-nasal-cancer-caused-cushings-syndrome-case-report-says/

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