Effects of Long-Acting Somatostatin Analogues on Lipid Metabolism in Patients with Newly Diagnosed Acromegaly: A Retrospective Study of 120 Cases.

The short-term effects of long-acting somatostatin analogues (SSAs) on lipid profiles in patients with acromegaly are not well studied. We retrospectively analyzed the effects of SSAs on lipid profiles and associated cardiovascular risk factors in a cohort of 120 newly diagnosed acromegaly patients. In this study, 69 females and 51 males were included. These patients were treated with either octreotide LAR (OCT) or lanreotide SR (LAN) for 3 months. After SSAs treatment, both GH and IGF-1 significantly decreased (p<0.001). Triglyceride (TG), total to high-density lipoprotein cholesterol (HDL-C) ratio, and lipoprotein (a) [Lp(a)] levels were significantly decreased, while HDL-C levels were increased (p<0.05). The reduction of mean serum GH (GHm) was positively associated with the decrease of TG (r=0.305, p=0.001) and Lp(a) (r=0.257, p=0.005), as well as the increase of HDL-C (r=-0.355, p<0.001). The changes of lipid profiles were observed only in OCT group, but not in LAN group. In addition, systolic blood pressure (SBP) had significantly declined after SSAs treatment, with an average reduction of 4.4 mmHg (126.7±1.28 vs. 122.3±1.44 mmHg, p=0.003), while no change was observed regarding diastolic blood pressure (DBP) (p>0.05). Fasting insulin, fasting C-peptide, and HOMA-IR were significantly decreased after SSAs treatment. In conclusion, our current study revealed that short-term SSAs treatment improves lipid profiles and other cardiovascular risk factors in patients with acromegaly.

Primary hypothyroidism and isolated ACTH deficiency induced by nivolumab therapy: Case report and review.

RATIONALE: Nivolumab is a monoclonal IgG antibody blocking programmed death receptor-1 (PD1), leading to restoration of the natural T-cell-mediated immune response against the cancer cells. However, it also causes plenty of autoimmune-related adverse events, which often involves endocrine system. PATIENT CONCERNS: A 54-year-old male with renal clear cell carcinoma was treated with nivolumab intravenously. Routine monitoring showed elevated thyroid-stimulating hormone and low free thyroxine after the 6th administration of nivolumab. After the 12th administration, he developed general fatigue, recurrent hypoglycemia, and relative hypotension. Laboratory tests showed low sodium, low morning cortisol without correspondence increase of corticotrophin (ACTH). Other pituitary hormones were normal. MRI showed no space-occupying lesions, but heterogeneous enhancement of the pituitary gland. DIAGNOSES: Primary hypothyroidism and isolated ACTH deficiency. The etiologies were assumed to be nivolumab induced autoimmune lymphocytic thyroiditis and hypophysitis, respectively. INTERVENTIONS: Hormone replacements with levothyroxine and acetate cortisone were given orally. Nivolumab was adjusted to lower dose and longer interval. OUTCOMES: The patient felt good after adequate replacement. Nivolumab was returned to routine dose and interval six months later. And the metastasis was not obviously progressed during this time. LESSONS: The present report provides the first detailed presentation of combined hypothyroidism and isolated ACTH deficiency induced by nivolumab. Adrenal deficiency often develops insidiously. We suggest routine monitoring of fasting blood-glucose, blood pressure and serum sodium as well as thyroid function during nivolumab and other cancer immunotherapies. When unexpected fatigue, hypoglycemia, hypotension or hyponatremia appeared, adrenal deficiency should be taken into consideration.

Recurrent gain-of-function USP8 mutations in Cushing's disease.

Cushing's disease, also known as adrenocorticotropic hormone (ACTH)-secreting pituitary adenomas (PAs) that cause excess cortisol production, accounts for up to 85% of corticotrophin-dependent Cushing's syndrome cases. However, the genetic alterations in this disease are unclear. Here, we performed whole-exome sequencing of DNA derived from 12 ACTH-secreting PAs and matched blood samples, which revealed three types of somatic mutations in a candidate gene, USP8 (encoding ubiquitin-specific protease 8), exclusively in exon 14 in 8 of 12 ACTH-secreting PAs. We further evaluated somatic USP8 mutations in additional 258 PAs by Sanger sequencing. Targeted sequencing further identified a total of 17 types of USP8 variants in 67 of 108 ACTH-secreting PAs (62.04%). However, none of these mutations was detected in other types of PAs (n = 150). These mutations aggregate within the 14-3-3 binding motif of USP8 and disrupt the interaction between USP8 and 14-3-3 protein, resulting in an elevated capacity to protect EGFR from lysosomal degradation. Accordingly, PAs with mutated USP8 display a higher incidence of EGFR expression, elevated EGFR protein abundance and mRNA expression levels of POMC, which encodes the precursor of ACTH. PAs with mutated USP8 are significantly smaller in size and have higher ACTH production than wild-type PAs. In surgically resected primary USP8-mutated tumor cells, USP8 knockdown or blocking EGFR effectively attenuates ACTH secretion. Taken together, somatic gain-of-function USP8 mutations are common and contribute to ACTH overproduction in Cushing's disease. Inhibition of USP8 or EGFR is promising for treating USP8-mutated corticotrophin adenoma. Our study highlights the potentially functional mutated gene in Cushing's disease and provides insights into the therapeutics of this disease.