Inhibition Of Steroidogenesis Research Articles

Vertebrate endocrine disruptors induce sex-reversal in blue mussels

Mollusks are the second most diverse animal phylum, yet little is known about their endocrinology or how they respond to endocrine disrupting compound (EDC) pollution. Characteristic effects of endocrine disruption are reproductive impairment, skewed sex ratios, development of opposite sex characteristics, and population decline. However, whether classical vertebrate EDCs, such as steroid hormone-like chemicals and inhibitors of steroidogenesis, exert effects on mollusks is controversial. In the blue mussel, Mytilus edulis, EDC exposure is correlated with feminized sex ratios in wild and laboratory mussels, but sex reversal has not been confirmed. Here, we describe a non-destructive qPCR assay to identify the sex of M. edulis allowing identification of males and females prior to experimentation. We exposed male mussels to 17α-ethinylestradiol and female mussels to ketoconazole, EDCs that mimic vertebrate steroid hormones or inhibit their biosynthesis. Both chemicals changed the sex of individual mussels, interfered with gonadal development, and disrupted gene expression of the sex differentiation pathway. Impacts from ketoconazole treatment, including changes in steroid levels, confirmed a role for steroidogenesis and steroid-like hormones in mollusk endocrinology. The present study expands the possibilities for laboratory and field monitoring of mollusk species and provides key insights into endocrine disruption and sexual differentiation in bivalves.

7963 Analysis of the inhibition of adrenal synthesis and peripheral metabolism of corticosteroids by oteseconazole and two preclinical tetrazole antifungals

Abstract Disclosure: M. Jäger: None. V. González-Ruiz: None. F.L. Joos: None. D.V. Winter: None. J. Boccard: None. T. Degenhardt: Employee; Self; Mycovia Inc. S. Brand: Employee; Self; Mycovia Inc.. S. Rudaz: None. G.R. Thompson: None. A. Odermatt: None. The triazole antifungals posaconazole and itraconazole can cause pseudohyperaldosteronism with hypertension and hypokalemia by blocking adrenal cortisol synthesis and its peripheral inactivation [1]. Mechanisms of pseudohyperaldosteronism include inhibition of adrenal cytochrome P450 enzymes CYP11B1 and CYP17A1, as well as peripherally expressed 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2). To enhance specificity for fungal CYP51, tetrazole compounds have been developed [2]. Here, we used adrenal H295R cells and enzyme activity assays to assess the inhibition of steroidogenesis by the tetrazoles oteseconazole, VT-1129 and VT-1598. In addition, the three tetrazoles were tested for inhibition of 11β-HSD2. Steroidomic footprint analyses of H295R cell supernatants using untargeted LC-HRMS with steroid annotation indicated common features of the oteseconazole and VT-1129 patterns with that of the triazole itraconazole, and similarities between VT-1598 and the triazole isavuconazole. Targeted quantification of nine adrenal steroids by UHPLC-MS/MS in supernatants of treated H295R cells showed an overall inhibition of steroidogenesis by the tetrazoles and the triazoles itraconazole and isavuconazole. Experiments using recombinant human enzymes suggested that this effect is not caused by direct inhibition of steroidogenic enzymes because no or very weak inhibition could be observed. Furthermore, oteseconazole, VT-1129 and VT-1598 did not inhibit 11β-HSD2, suggesting that they unlikely cause pseudohyperaldosteronism. Further research needs to uncover the exact mechanism for the observed overall inhibition of steroidogenesis by the tetrazoles as well as itraconazole and isavuconazole, and whether concentrations reached in patients are high enough to cause adrenal insufficiency and hyperplasia.

7573 Cyclic Cushing’s Syndrome: Periodicity and Treatment Outcome in an International Multicenter Case Series

Abstract Disclosure: E. Nowak: None. M. Fleseriu: Consulting Fee; Self; Recordati Rare Diseases, Sparrow, Xeris Pharmaceuticals. Grant Recipient; Self; Recordati Rare Diseases, Sparrow, Xeris Pharmaceuticals. Q. Zhang: None. S. Zhang: None. K.C. Yuen: Grant Recipient; Self; Corcept, Sparrow. A. Gilis-Januszewska: None. F.A. Hanzu: None. N. Matikainen: None. M. Minasyan: None. R. Pichler: None. M. Araujo-Castro: None. E. Arvat: None. F. Bioletto: None. K. Isand: None. J.A. Wass: None. M. Reincke: Consulting Fee; Self; Recordati Rare Diseases, HRA Pharma, Crinetics, Lundbeck Pharmaceuticals. Grant Recipient; Self; Recordati Rare Diseases, HRA Pharma, Crinetics, Lundbeck Pharmaceuticals. Background: Cyclic Cushing’s syndrome (cCS) is characterised by variable cortisol secretion periodicity (peaks and throughs); it is marked by diagnostic errors, and possibly poorer overall outcome. Patients and Methods: We investigated cycle characteristics, diagnostic and treatment modalities in patients (pts) with CS from invited expert endocrine centers. cCS was defined as at least 2 clinical and biochemical hypercortisolaemic peaks (high) and 1 spontaneous eu-/or hypocortisolaemic (AI) trough (low) cortisol. Data was extracted from pts charts and transferred into a central database. Ethics approval was obtained centrally and locally. Statistical analysis was conducted with GraphPad Prism 10.1.1. Results: We included 37 pts (70% females) from 12 centers, 20 (54%) with pituitary (pit), 6 (16%) with ectopic, and 11 (30%) with occult tumour origin (suspected 10 ectopic, 1 pit). 24-h urine free cortisol (UFC) was the main diagnostic biomarker used to determine cyclicity; median 14.67 X ULN for peaks (IQR 3.58-45.92) and 0.29 X ULN for troughs (IQR 0.20-0.57). On average, pts experienced 3.11 peaks (± 1.34); 83% occurred at irregular intervals, separated by troughs lasting several months. Pts with suspected/proven ectopic cCS had significantly more peaks (mean 3.75 ± 1.57) vs pit cCS (mean 2.70 ± 0.92; p=0.023) and significantly higher levels of cortisol excess (p<0.05). Twenty-eight (76%) pts had symptoms worsening during peaks. Twelve (32%) pts had spontaneous AI phases. Only 69% of BIPSS were performed during hypercortisolism. In pts with suspected ectopic cCS, imaging was suggestive in 44%. Twenty-four (65%) pts had surgery (19 pit, 5 ectopic), four (11%) had radiation, and 2 (5%) bilateral adrenalectomy. Steroidogenesis inhibitors (SI) were used in 20 (54%) cases; 13 (65%) as titration regimen. After a median follow-up of 42.0 months (IQR 25.50-84.50), 17 (46%) pts achieved therapy-induced remission, 4 (11%) full spontaneous and five (14%) partial remission. Five pts were clinically and biochemically controlled by SI, 5 had persistent overt CS, and 1 (3%) died due to pneumonia pre-therapy. Median time to therapy-induced remission after referral to our centers was 34.0 months (IQR 4.25-58.50). A delayed diagnosis or therapy due to misleading findings was noted in 41% and 38% respectively. Conclusion: Cortisol secretion kinetics is highly variable in CS, with clearly defined cycles of hyper-, eu- and hypocortisolemia in some pts. Here, we show that cCS remains a challenging disease entity even in specialised centers, with less than half of the pts achieving remission at 3.5 years. Despite unpredictable cycle length and amplitude and risk of spontaneous AI, steroidogenesis inhibitors were frequently used in a titration rather than block and replace approach. Better understanding of cortisol secretion kinetics and periodicity may improve diagnostic accuracy and individualised care. Presentation: 6/1/2024

7594 Diagnostic utility of 11C-Methionine PET-CT imaging in persistent or recurrent Cushing’s disease after transsphenoidal surgery

Abstract Disclosure: R. Furnica: None. F. Devuyst: None. C. Mathey: None. S. Constantinescu: None. C. De Herdt: None. L. Renaud: None. D.M. Maiter: None. Introduction: Equivocal or negative pituitary magnetic resonance imaging (MRI) findings pose a significant challenge in the management of persistent or recurrent Cushing’s disease (CD), compromising the chances of success of a further transsphenoidal surgery (TSS). The aim of our study was to determine the diagnostic utility of [1][1]C-methionine (MET) positron emission tomography coupled with computerized tomography (PET-CT) in localizing the residual corticotroph adenoma. Methods: We retrospectively analyzed the results of all MET-PET-CT performed between May 2002 and November 2023 in patients with a CD persisting or relapsing after TSS, and equivocal (n=14) or negative pituitary MRI findings (n=8). In 15 cases, images obtained from MET-PET were also co-registered with a high-resolution 3D pituitary MRI. All patients had a pathologically confirmed corticotroph tumor, and/or biochemical evidence of early postoperative remission after the first TSS, and/or proven ACTH-dependent Cushing’s syndrome with positive bilateral inferior petrosal sinus sampling. Results: Twenty-two patients were included (18 females and 4 males), with a mean age of 35.5 years at diagnosis. Initial tumors were mostly microadenomas with a mean tumor volume of 15 mm3. Thirteen out of the 22 patients had a suspect anomaly on conventional MRI that could however not be clearly distinguished from postsurgical changes, while the remaining 9 had a negative MRI. A significant MET standardized uptake value (SUV) in the suspected area of the tumor residue was defined as a ratio ≥ 1.80 relative to cerebellum SUV and was found in 12/22 patients (55%; 4 patients with negative pituitary MRI and 8 with equivocal findings). On the basis of positive imaging, repeat TSS was performed in 10 patients and was successful in 6, while Gamma Knife radiosurgery (GKRS) was performed in 2 patients allowing remission in both (total remission rate: 8/12). Among the 4 patients not cured by TSS, the presence of corticotroph adenoma in the resected tissue was found in 3 cases. Exploratory TSS was performed in 4 of the 10 PET negative patients, with no remission. Two patients were treated with GKRS, with remission in 1 case. Among the 4 other patients, bilateral adrenalectomy was performed in one case and adrenal steroidogenesis inhibitors were used in the remaining patients. Conclusions: [1][1]C-Methionine PET-CT imaging can provide valuable diagnostic information to detect a residual active corticotroph adenoma in about half of patients with a persistent or recurrent CD and equivocal or negative MRI results, thereby allowing targeted TSS or radiosurgery with a global success rate of 67% in this selected subpopulation. Presentation: 6/1/2024

9272 Diagnostic utility of 11C-Methionine PET-CT imaging in persistent or recurrent Cushing’s disease after transsphenoidal surgery

Abstract Disclosure: R. Furnica: None. F. Devuyst: None. C. Mathey: None. S. Constantinescu: None. C. De Herdt: None. L. Renaud: None. D.M. Maiter: None. Introduction: Equivocal or negative pituitary magnetic resonance imaging (MRI) findings pose a significant challenge in the management of persistent or recurrent Cushing’s disease (CD), compromising the chances of success of a further transsphenoidal surgery (TSS). The aim of our study was to determine the diagnostic utility of [1][1]C-methionine (MET) positron emission tomography coupled with computerized tomography (PET-CT) in localizing the residual corticotroph adenoma. Methods: We retrospectively analyzed the results of all MET-PET-CT performed between May 2002 and November 2023 in patients with a CD persisting or relapsing after TSS, and equivocal (n=14) or negative pituitary MRI findings (n=8). In 15 cases, images obtained from MET-PET were also co-registered with a high-resolution 3D pituitary MRI. All patients had a pathologically confirmed corticotroph tumor, and/or biochemical evidence of early postoperative remission after the first TSS, and/or proven ACTH-dependent Cushing’s syndrome with positive bilateral inferior petrosal sinus sampling. Results: Twenty-two patients were included (18 females and 4 males), with a mean age of 35.5 years at diagnosis. Initial tumors were mostly microadenomas with a mean tumor volume of 15 mm3. Thirteen out of the 22 patients had a suspect anomaly on conventional MRI that could however not be clearly distinguished from postsurgical changes, while the remaining 9 had a negative MRI. A significant MET standardized uptake value (SUV) in the suspected area of the tumor residue was defined as a ratio ≥ 1.80 relative to cerebellum SUV and was found in 12/22 patients (55%; 4 patients with negative pituitary MRI and 8 with equivocal findings). On the basis of positive imaging, repeat TSS was performed in 10 patients and was successful in 6, while Gamma Knife radiosurgery (GKRS) was performed in 2 patients allowing remission in both (total remission rate: 8/12). Among the 4 patients not cured by TSS, the presence of corticotroph adenoma in the resected tissue was found in 3 cases. Exploratory TSS was performed in 4 of the 10 PET negative patients, with no remission. Two patients were treated with GKRS, with remission in 1 case. Among the 4 other patients, bilateral adrenalectomy was performed in one case and adrenal steroidogenesis inhibitors were used in the remaining patients. Conclusions: [1][1]C-Methionine PET-CT imaging can provide valuable diagnostic information to detect a residual active corticotroph adenoma in about half of patients with a persistent or recurrent CD and equivocal or negative MRI results, thereby allowing targeted TSS or radiosurgery with a global success rate of 67% in this selected subpopulation. Presentation: 6/1/2024

6426 Pregnancy-induced ACTH-independent Cushing Syndrome: A Rare Phenomenon Secondary To Aberrant Receptors On Adrenal Glands

Abstract Disclosure: K. Manglani: None. S.T. Sharma: None. Pregnancy-induced hypercortisolism is a rare phenomenon with very few cases reported in the literature. The pathogenesis is thought to be secondary to the expression of aberrant LH/hCG receptors on the adrenal gland that stimulate cortisol production in pregnancy. We present a case of a 31-year-old female with no past comorbidities until her first pregnancy in 2017 when she gained around 50lbs, developed violaceous striae, acne, hirsutism, depression with suicidal ideation for which she was hospitalized twice, and underwent emergent C-section at 34 weeks’ gestation due to pre-eclampsia. She was referred to the Endocrinology clinic post-delivery, and screening for Cushing syndrome was negative at that time: 24-hour urinary free cortisol (UFC), late-night salivary cortisol (LNSC) and 1-mg dexamethasone (dex) suppression test (DST) were normal. She presented again in 2020 during her second pregnancy at 14 weeks gestation, with 20lb weight gain in the first trimester, acne, hirsutism, and easy bruising. Labs showed cortisol of 22.4 mcg/dL (6.2-19.4), ACTH <1.5 pg/mL, total testosterone 168 ng/dL (8-48), androstenedione 751 ng/dL (41-262), DHEAS 91.2 mcg/dL (84.8-378), 24-hour UFC 277 mcg/day (6-42), LNSC 0.671 mcg/dL, 1mg DST with post-dex cortisol 24 mcg/dL (dex level 58 ng/dL), and 8-mg DST with post-dex cortisol level of 28.2 mcg/dL (dex level 457 ng/dL). Testing was consistent with ACTH-independent Cushing syndrome. Ultrasound and MRI of the abdomen/pelvis showed normal adrenal glands with no hyperplasia or mass. Given worsening hypercortisolism and her course during a prior pregnancy, medical treatment with metyrapone was initiated. We started at a dose of 500 mg daily and gradually increased to 1500 mg with close monitoring of her blood pressure and cortisol levels. She underwent vaginal delivery at 38 weeks’ gestation, and the baby required a brief stay in the NICU for respiratory distress but was otherwise doing well. The patient developed secondary adrenal insufficiency post-delivery requiring hydrocortisone, with recovery of her HPA axis in around 10 weeks. Since then, she has been off hydrocortisone with normal UFC, ACTH, and cortisol levels. This case enables discussion regarding the underlying etiology, diagnostic difficulties, and management of this rare condition. Although the exact etiology is unknown, the postulated mechanism is aberrant LH/hCG receptor expression given the patient’s presentation during each pregnancy, normal cortisol levels between both pregnancies, and a brief period of adrenal insufficiency post-delivery. Management of hypercortisolism during pregnancy remains challenging. Metyrapone, a steroidogenesis inhibitor, can be considered for control of hypercortisolemia during pregnancy (off-label) in select cases to prevent maternal and fetal complications. Presentation: 6/1/2024

6409 Successful Treatment Of Severe Ectopic ACTH-dependent Cushing’s Syndrome With Osilodrostat

Abstract Disclosure: K.A. Lee: None. C. Mendes Pessoa: None. W. Huang: Consulting Fee; Self; WH, Honoraria from Consulting and Speaking received from Recordati Rare Disease. Background: Cushing’s syndrome due to ectopic ACTH secretion is rare and may progress rapidly, making treatment very challenging. Previous case reports have described therapeutic options including adrenal steroidogenesis inhibitors, bilateral adrenalectomy (BAL), and adrenal embolization with success. Clinical Case: A 27-year-old woman with metastatic neuroendocrine tumor presented with sudden onset and rapidly progressing symptoms of fatigue, muscle weakness, acne and weight gain within two weeks. Laboratory findings confirmed severe Cushing’s syndrome due to ectopic ACTH secretion: AM cortisol 173.4 µg/dL (5-25), ACTH 1425 pg/mL (7.2-63.3), 24 hour urine cortisol 29,498 mcg/24hr (4-50), DHEA-Sulfate 1314 µg/dL (65 - 380), and testosterone 133 ng/dL (0-100). She was also found to have severe hypokalemia, hypocalcemia and hyperglycemia (despite an HbA1C of 6.2 at 2 weeks before presentation). CT- scan showed diffuse thickening of the bilateral adrenal glands. Due to widely metastatic disease in the peritoneum, BAL was considered non-feasible. The patient was admitted to hospital and initiated on osilodrostat at 20mg twice daily (after correction of hypokalemia) with close monitoring of her electrolytes, cortisol, EKG and steroid withdrawal symptoms. There was a rapid improvement of cortisol levels in response to osilodrostat. During treatment, she developed steroid withdrawal symptoms for which she was started on medium dose hydrocortisone. Bilateral adrenal arterial embolization was attempted but ultimately needed to be converted to right only adrenal gland embolization due to a hypertensive urgency and difficulty with catheterization. Her symptoms of Cushing’s syndrome significantly improved with the treatment. During her hospitalization, her hypokalemia was managed with spironolactone and potassium supplement, hypocalcemia with calcium supplement, and hyperglycemia with basal and bolus insulins. With significant improvement of cortisol levels, her hypocalcemia and hyperglycemia resolved and required no further treatment. Her potassium levels normalized and spironolactone was stopped. She remains on potassium supplement to keep K level at upper half of normal range to avoid long QTc. After discharge, her morning cortisol levels (before morning dose of hydrocortisone) continued to decrease and her osilodrostat dose was gradually tapered to 5mg once daily at night. Hydrocortisone was continued as part of the block-and-replace regimen. Conclusion: This case described a unique sudden onset and rapid progression of ectopic ACTH dependent Cushing’s syndrome and successful utilization of a block-and-replace approach by using the steroidogenesis inhibitor osilodrostat in prompt control of the hypercortisolism and related comorbidities. We also explored the feasibility of adrenal embolization for definitive management in the context of unfeasible BAL. Presentation: 6/2/2024

6372 Changes in Blood Steroid Hormone Profile after Switching from Metyrapone to Osilodrostat

Abstract Disclosure: K. Yokozeki: None. H. Kameda: None. A. Miya: None. H. Nomoto: None. A. Nakamura: None. S. Jin: None. K. Matoba: None. T. Atsumi: None. Background: The new steroidogenesis inhibitor osilodrostat has recently been approved for use in Cushing's syndrome. However, there are limited studies on changes in blood steroid hormone profiles after switching from existing drugs including metyrapone. Purpose: To study the changes in steroid hormone profiles with switching from metyrapone to osilodrostat in patients with Cushing's disease and to examine the differences in clinical efficacy. Case 1: A woman in her 40s underwent transsphenoidal pituitary tumor surgery (TSS) for Cushing's disease in X-12, but was not in remission and was treated with 1000 mg/day of metyrapone and oral hydrocortisone. In X-3, the patient complained of masculinization and was started pasireotide LAR 10 mg per month, which was subsequently increased to 30 mg. Despite the addition of 240 mg/day of trilostane in X-2, the patient did not show improvement. Switched the steroidogenesis inhibitors to osilodrostat 4 mg/day in year X, blood cortisol and testosterone levels decreased and the symptoms of virilization disappeared.Case 2: A woman in her 40s experienced edema in her face and limbs, increased appetite and weight gain since Y-13. After endocrinological examination, she was diagnosed with Cushing's disease. TSS was performed and she was in remission. However, she suffered a relapse in Y-4 and was started on metyrapone, which was titrated up to 4,000 mg/day. Due to gastric discomfort, metyrapone was switched to osilodrostat 52 mg/day in year Y, leading to an improvement of her gastric symptoms and stabilized blood cortisol level. Case 3: A woman in her 70s underwent TSS for Cushing's disease in Z-6, but the tumor remained and she was prescribed metyrapone 1,500 mg/day. The disease was stable and complications were under control with metyrapone. In Z-1, the patient developed elevated blood pressure and worsening leg edema, and metyrapone was switched to osilodrostat 3 mg/day in year Z, resulting decreased blood cortisol level and blood pressure. Results: Liquid chromatograph mass spectrometry (LC-MS) analysis of blood steroid hormone profiles in above three cases demonstrated a decrease in 17-OH pregnenolone, 17-OH progesterone, and 11-deoxycorticosterone after switching the steroidogenesis inhibitors. Discussion and Conclusion: It has been noted that osilodrostat lowers serum cortisol in a shorter period of time compared to metyrapone and may also decrease the number of antihypertensive medications used. Under metyrapone administration, hypertrichosis, hypertension, and hypokalemia are often observed with increased mineralocorticoid precursors, but osilodrostat may have a different clinical effect as a result of its different pattern of steroid hormone synthase inhibition. Presentation: 6/2/2024

6570 Treatment of Cushing’s With Levoketoconazole: A Case Series

Abstract Disclosure: N. Chamorro-Pareja: None. M. Haines: None. L.E. Dichtel: Consulting Fee; Self; Lumos Pharma. Research Investigator; Self; Recordati, NovoNordisk, Perspectum Ltd, Lumos Pharma, Pfizer, Inc.. Stock Owner; Self; Marea Therapeutics. Other; Self; Third Rock Ventures. B.M. Biller: Consulting Fee; Self; Xeris Pharmaceuticals, Recordati Rare Diseases, Sparrow, Lundbeck. Background: Endogenous Cushing’s syndrome (CS) is a rare condition of excess cortisol secretion; the most common cause is a pituitary corticotroph tumor (Cushing’s disease [CD]). Medical treatment for CD is primarily used to control hypercortisolism in patients with persistent or recurrent disease after transsphenoidal surgery (TSS). Levoketoconazole (LKCZ), a steroidogenesis inhibitor, was FDA approved in January 2022 for CS treatment. This reports 3 cases of patients who were treated with LKCZ for recurrent CS. Clinical Cases: Case 1: 44-year-old (yo) male (M) with a history of CD with urinary free cortisol (UFC) >26x upper limit of normal (ULN) who was treated preoperatively with ketoconazole (KCZ) 1000 mg/day with UFC improved to 6x ULN. KCZ was discontinued at TSS, and he achieved remission post-operatively. He was lost to follow-up and re-presented after several years with worsening hypertension, muscle weakness, edema, and anxiety with UFC 28x ULN and a recurrent pituitary lesion on MRI. He declined repeat TSS and underwent radiation therapy (RT) and medical treatment. LKCZ was initiated at 150 mg twice daily (BID) and increased to 300 mg BID. At LKCZ 300 mg BID, he had a low UFC and mild nausea but an adequate serum morning cortisol (10.4 ug/dL, ref:6-18.4 ug/dL); LKCZ was reduced to 150 mg BID with resolution of symptoms (sxs) and normal UFC. Case 2: 56 yo M with a history of CD (UFC >3x ULN) who underwent 2 TSSs and RT over 10 years prior with eventual remission, but later recurred. Sxs included brain fog and mood disturbances. He achieved control with pasireotide but discontinued due to abnormal liver function tests. He was then treated with KCZ 400 mg/day but remained hypercortisolemic (LNSC 1.1x ULN) and was interested in trying a new medication, so was switched to LKCZ 150 mg BID with significant improvement of sxs and normalization of LNSC. Case 3: 54 yo F with presumed cyclic CD (negative whole-body and octreotide scans) with UFC 1.7x ULN and LNSC 3x ULN. TSS was performed with negative pathology; she had persistent hypercortisolemia and sxs including insomnia, fatigue, and mood disturbances. She was intolerant to and/or uncontrolled on 4 medications, including KCZ at 1000 mg/day that was discontinued due to a rash. She was started on LKCZ 150 mg BID and achieved normal LNSC and UFC after about 1 month. The drug was discontinued due to the development of a rash similar to that with KCZ. Conclusion: LKCZ is a new option for the treatment of CS in patients whose disease persists after TSS. These 3 patients had improvement of sxs and normalization of cortisol levels while on LKCZ, although one patient discontinued LKCZ due to a rash that was previously experienced with KCZ. The other two patients are being carefully monitored for liver function test elevation, QTc abnormalities and adrenal insufficiency with no issues to date. To our knowledge, this is the first case series of CS patients treated clinically with LKCZ. Presentation: 6/1/2024

6702 Management And Complications Of Metastatic Adrenocortical Carcinoma Presenting With Severe Cushing Syndrome

Abstract Disclosure: S. Rodrigues: None. A.K. Sumal: None. Background: Metastatic adrenocortical carcinoma (ACC) presenting with Cushing syndrome (CS) is a complicated, aggressive disease that commonly requires multiple adrenal steroidogenesis inhibitors and chemotherapy to achieve hormonal and tumor control. Clinical Case: A 66-year-old man with a history of prostate cancer and hypertension presented with right flank and back pain, worsening type 2 diabetes, profound proximal muscle weakness, and 3+ lower extremity edema to his thighs. CT and PET-CT revealed a 10.9 cm right adrenal mass with pericaval lymphadenopathy and metastatic disease at the L2 vertebral body. Laboratory testing demonstrated evidence of hypercortisolism with elevated 24-hour urinary cortisol excretion (449 mcg/24h; n<45 mcg/24h), and abnormal 1 mg dexamethasone suppression test (cortisol 15 mcg/dL; n< 1.8 mcg/dL) with suppressed ACTH (<6 pg/mL; n=7-63 pg/mL). Surgical resection of the primary tumor was aborted intraoperatively given the discovery of new peritoneal metastases, which were confirmed by biopsy to be metastatic ACC. He was started on mitotane and osilodrostat to manage his severe CS. He was also started on dexamethasone, both to prevent adrenal insufficiency and to avoid influencing serum cortisol measurements used to assess disease control. However, given his significant peripheral edema and weakness, he was functionally unable to receive chemotherapy. Despite rapid uptitration of mitotane and osilodrostat over three weeks, his CS remained uncontrolled, and he was ultimately hospitalized for lower extremity paralysis and septic shock due to pyelonephritis. Repeat imaging revealed severe spinal canal stenosis from an L2 pathologic fracture, as well as worsening hepatic, osseous, peritoneal, and retroperitoneal metastases. After recovery from his septic shock, he was started on chemotherapy with carboplatin and etoposide while hospitalized, but his mitotane was intermittently held due to elevated transaminases. His hospital course was complicated by hypotension requiring pressor support, atrial fibrillation, hemoperitoneum, worsening anasarca, and acute kidney injury requiring continuous renal replacement therapy. Given his worsening condition that precluded him from further chemotherapy or palliative radiation, he elected to pursue comfort care measures and expired shortly thereafter. Conclusion: This case highlights the therapeutic challenges of metastatic ACC presenting with life-threatening CS. Simultaneous use of multiple adrenal steroidogenesis inhibitors is often required for control of hypercortisolism, and chemotherapy is equally necessary to manage tumor burden. However, as in this case, disease-related complications can limit treatment management and result in rapid deterioration. Thus, early diagnosis and prompt treatment of metastatic ACC presenting with CS is critical to prevent morbidity and mortality. Presentation: 6/3/2024

8281 Continuous Low-Dose Etomidate Infusion For The Management Of Severe Hypercortisolism In Metastatic Adrenocortical Carcinoma

Abstract Disclosure: A. Jamil: None. N. Mohammad: None. S. Narayana: None. Background: Adrenocortical carcinoma (ACC) is a rare endocrine malignancy of the adrenal glands with a poor prognosis that often presents with excess hormone secretion. Approximately, 45% of cases present with hypercortisolism.1 A key component of management is achieving control of hypercortisolism. Though there are multiple enteral therapies that can inhibit cortisol production, few treatment options are available for use in critically ill patients who are not surgical candidates and cannot take oral medications. Though primarily known as a short-acting intravenous anesthetic agent used for sedation, etomidate also inhibits 11-β-hydroxylase, a key enzyme involved in corticosteroid biosynthesis.2 Clinical Case: A 28-year-old woman with metastatic adrenocortical carcinoma with associated hypercortisolism was initially admitted for anemia and thrombocytopenia, with an initial cortisol on admission of 29.3 μg/dl (normal range: 2.3-19.4 ug/dl). Due to her large tumor burden with metastasis to the liver and invasion into the inferior vena cava, she was deemed a poor surgical candidate with a poor overall prognosis. Her hospital course was complicated by acute hypoxemic respiratory failure requiring intubation, and thus her enteral steroidogenesis inhibitors (mitotane, ketoconazole, and metyrapone) were discontinued as none were administrable via nasogastric tube. Consequently, her hypercortisolism worsened rapidly with a cortisol level of 351.3 μg/dl , prompting initiation of continuous low-dose etomidate infusion, which resulted in significant improvements in her cortisol levels. After eight days of etomidate treatment, her cortisol levels reached a goal value of 25.0 μg/dl. However, she then suffered an ischemic cerebrovascular event and multiorgan failure, and was subsequently transitioned to hospice care. Conclusion: Low-dose etomidate infusion is an effective therapeutic agent for hypercortisolism in patients with ACC that are unable to take oral medications.

Dysregulation of mitochondrial dynamics and mitophagy are involved in high-fat diet-induced steroidogenesis inhibition

Male obesity is a pandemic health issue and can disrupt testicular steroidogenesis. Here, we explored the mechanism by which a high-fat diet (HFD) induced steroidogenic inhibition. As expected, HFD induced lipid droplet accumulation and reduced the expression of StAR, P450scc, and 3β-HSD, three steroidogenic enzymes, in mouse testes. Palmitic acid (PA), a saturated fatty acid usually used to trigger lipotoxicity in vitro, induced greater accumulation of lipid droplets and the downregulation of steroidogenic enzymes in TM3 cells. Mechanistically, both HFD and PA disturbed mitochondrial fusion/fission dynamics and then induced mitochondrial dysfunction and mitophagy inhibition in mouse Leydig cells. Additionally, mitochondrial fusion promoter M1 attenuated PA-induced imbalance of mitochondrial dynamics, mitophagy inhibition, mitochondrial reactive oxygen species (ROS) production, and mitochondrial dysfunction in TM3 cells. Mitofusin 2 (MFN2) knock-down further aggravated the PA-induced imbalance of mitochondrial dynamics, mitochondrial ROS production, and mitochondrial dysfunction in TM3 cells. Importantly, M1 rescued PA-induced downregulation of steroidogenic enzymes, whereas MFN2 knock-down further aggravated PA-induced downregulation of steroidogenic enzymes in TM3 cells. Overall, our results provide laboratory evidence that mitochondrial dysfunction and mitophagy inhibition caused by dysregulation of mitochondrial fusion may be involved in HFD-induced steroidogenesis inhibition in mouse Leydig cells.

How to manage Cushing's disease after failed primary pituitary surgery.

The first-line treatment for Cushing's disease is transsphenoidal adenomectomy, which can be curative in a significant number of patients. The second-line options in cases of failed primary pituitary surgery include repeat surgery, medical therapy, and radiation. The role for medical therapy has expanded in the last decade, and options include pituitary-targeting drugs, steroid synthesis inhibitors, and glucocorticoid receptor antagonists. Bilateral adrenalectomy is a more aggressive approach, which may be necessary in cases of persistent hypercortisolism despite surgery, medical treatment, or radiation or when rapid normalization of cortisol is needed. We review the available treatment options for Cushing's disease, focusing on the second-line treatment options to consider after failed primary pituitary surgery.

Medical Therapy of Endogenous Cushing's Syndrome with Steroidogenesis Inhibitors: Treatment Rationale, Available Drugs, and Therapeutic Effects.

Endogenous Cushing's syndrome (CS) is a rare disease characterized by a glucocorticoid excess. If inadequately treated, hypercortisolism can lead to increased morbidity and mortality. Surgical removal of the underlying tumor is the first-line treatment but is sometimes not feasible or even contraindicated. Additionally, in cases with severe CS, rapid control of hypercortisolism may be required. In these scenarios, steroidogenesis inhibitors represent a therapeutic alternative to surgery. Over the last years, the knowledge of the broad therapeutic effects of steroidogenesis inhibitors per se and the number of available drugs have increased. However, large comparative studies are still lacking. Accordingly, the decision on which drug to be used in a certain patient or clinical setting may be difficult. This review aims to summarize the main characteristics of steroidogenesis inhibitors.

Medical treatment of functional pituitary adenomas, trials and tribulations.

Functioning pituitary adenomas (FPAs) include most frequently prolactinomas, somatotroph or corticotroph adenomas, while thyrotroph and gonadotroph adenomas are very rare. Despite their benign histological nature (aggressive tumors are rare and malignant ones exceptional), FPAs could cause significant morbidity and increased mortality due to complications associated with hormonal excess syndromes and/or mass effect leading to compression of adjacent structures. This mini review will focus on the increasing role of medical therapy in the multimodal treatment, which also includes transsphenoidal surgery (TSS) and radiotherapy. Most patients with prolactinomas are treated only with medications, but surgery could be considered for some patients in a specialized pituitary center, if higher chances of cure. Dopamine agonists, especially cabergoline, are efficient in reducing tumor size and normalizing prolactin. TSS is the first-line treatment for all other FPAs, but most patients require complex adjuvant treatment, including a combination of therapeutic approaches. Medical therapy is the cornerstone of treatment in all patients after unsuccessful surgery or when surgery cannot be offered and includes somatostatin receptor ligands and dopamine agonists (almost all FPAs), growth hormone receptor antagonists (acromegaly), adrenal steroidogenesis inhibitors and glucocorticoid receptor blockers (Cushing's disease). Novel medical treatments, especially for acromegaly and Cushing's disease are under research. An enlarged panel of effective drugs available with increased knowledge of predictive factors for response and/or adverse effects will enhance the possibility to offer a more individualized treatment. This would not only improve disease control and prognosis, but also quality of life.

Steroidogenesis inhibitors in mild/subclinical cushing's syndrome: results from a retrospective cohort of patients

Steroidogenesis inhibitors in mild/subclinical cushing's syndrome: results from a retrospective cohort of patients

Abstract 6071: Identification of a molecular glue degrader targeting the full-length AR and AR-V7 splice variant

Abstract Prostate cancer is the most common cancer in males and the fifth leading cause of cancer mortality worldwide. A variety of therapeutic approaches exist including steroid synthesis inhibitors and next-generation ligand binding domain (LBD) antagonists [e.g., enzalutamide (Enza)]. However, these approaches are only effective against tumors bearing the full-length androgen receptor (AR-FL). In the course of their disease, many patients acquire androgen receptor splice variant 7 (AR-V7), a mutant form of the receptor which lacks the LBD and is constitutively activated. To date, no effective therapy has been demonstrated for patients with metastatic prostate cancer bearing the AR-V7 signature. We have recently developed a high throughput platform that allows for the identification of ligands that can bind to a wide variety of protein targets. Using this approach, we screened a diverse chemical library of 100,000 small molecules to identify compounds that are bound to AR-V7. One such molecule, AR-600, directly bound to AR-V7 and moreover, induced proteasomal-mediated targeted protein degradation of both AR-V7 and AR-FL. In prostate cancer cell lines expressing AR-FL, AR-600 induced a gene expression profile similar to cells treated with Enza including a marked reduction in KLK3 (PSA) expression. Moreover, AR-600 inhibited the growth of 22RV1 cells (IC50=23 nM), a cell line that predominantly expresses AR-V7, as well as C4-2 cells that express predominantly full-length AR (IC50=51 nM). In contrast, the compound did not affect the growth of a wide variety of non-tumorigenic cells, non-prostate tumor cell lines or PC3 cells, a prostate cell line that exhibits AR-independent cell growth (IC50>100uM). Preliminary exploration of the mechanism of action of AR-600 (M.W. ~300 Daltons) demonstrates the compound works as a molecular glue. These results thereby identify a small molecule glue degrader that can specifically induce the targeted protein degradation of the AR-V7 splice variant. Given the strong association of this isoform with treatment resistance, this approach would appear to provide an attractive strategy for patients with metastatic castration resistant prostate cancer. Citation Format: Yuan Liu, Mads B. Larsen, Bo Lin, Irene A. Cardenal, Jason Kennerdell, Toren Finkel, Bill B. Chen. Identification of a molecular glue degrader targeting the full-length AR and AR-V7 splice variant [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6071.

A23 IMPAIRMENT OF INTESTINAL CRYPTAL STEM CELL CYCLE AND PANETH CELL PROLIFERATION BY CHRONIC STRESS

Abstract Background The small intestine’s epithelial barrier is essential for intestinal homeostasis and host defense. It consists of epithelial cells that are constantly renewed by crypt stem cells and their progeny, which have different functions in the gut. Chronic stress can impair the barrier by modulating the gut-brain axis, which involves the hypothalamic-pituitary-adrenal (HPA) axis, the vagus nerve, and the immune system. Chronic stress can also alter the gut microbiota, which can further influence the barrier and immune system. Aims The present study examines how chronic stress affects the crypt stem cell niche and function in the small intestine. Methods Restraint stress was applied to 6-8 weeks old mice in a plastic container for 1 hour daily for 7 days. The dark/light transition box test was used to evaluate the stress-induced behavior change. The Ussing chamber technique was used to assess the paracellular permeability of the small intestine. RNA was extracted from the mucosa and submucosa layers of the small intestine, after removing the muscle layer, and RNA sequencing analysis was performed. Immunofluorescence analysis was also performed on the small intestinal tissues to detect the expression of various markers. To assess the in vivo effect of cortisol, dexamethasone (a synthetic steroid activating same receptors as cortisol), or metyrapone (an 11β-hydroxylation blocker to inhibit cortisol production), was applied to the mice. Results We found that restraint stress induced anxiety-like behavior, increased small intestinal epithelial permeability, and reduced villus and crypt length in mice. RNA sequencing analysis revealed that restraint stress upregulated steroid-driven pathways and downregulated cell cycle and cell mitosis pathways in the small intestinal mucosa, suggesting increased cortisol production and decreased stem cell activity. Immunofluorescence analysis confirmed that restraint stress reduced the expression of stem cell marker Olfm-4 and proliferation markers Ki-67 and p-H3 in the small intestinal crypts. Dexamethasone, a synthetic glucocorticoid, mimicked the effects of restraint stress on crypt stem cell proliferation, while metyrapone, a steroid synthesis inhibitor, attenuated the effects of restraint stress on crypt stem cell proliferation. Restraint stress and dexamethasone also reduced Paneth cell RNA expression and marker in the small intestine. Conclusions Chronic stress induces anxiety, barrier dysfunction, and epithelial shortening. Chronic stress also alters crypt stem cell and Paneth cell expression. These findings show how chronic stress impacts intestinal epithelial renewal and differentiation, which may affect intestinal health and disease. Funding Agencies JSPS

IN SILICO STUDIES FOR ANTI-BREAST CANCER ACMELLA OLERACEA (L.) FLOWERS

The study of the efficacy of Acmella oleracea (L.) flowers on breast cancer is still in its early stages. The molecular interaction mechanisms underlying Acmella oleracea's anti-breast cancer activity will be elucidated using in-silico analysis. For this study, seventeen bioactive compounds were used: spilanthol, alpha- and beta-amyrin ester, stigmasterol, beta-sitosterol, alpha-1-sitosterol, 3-acetylaleuritic acid, scopoletin, vanillic acid, trans-ferulic, (72,9E)-2-oxo-undeca-7,9-dienyl 3-methylbut-2-enoate, beta-caryophyllene, beta-pinene, myrcene, caryophyllene oxide, and limone Canonical smiles were obtained from PubChem and inserted into the PASS server to determine biological activity. Several compounds were docked with protein targets, such as ESR1, MAP2K2, and PGR. We used Pyrx 0.8 software for anchoring molecular interaction and Discovery Studio software to visualize the complex binding. In terms of Antineoplastic, apoptosis agonist, caspase-3, caspase-8 stimulant, ovulation inhibitor, steroid synthesis inhibitor, and TP53 expression enhancer, all the compounds tested positive for anticancer activity. According to Swiss ADME and protox analysis, Acmella oleracea flowers have the potential to modulate apoptosis and cell growth. More research is required to confirm the role of Acmella oleracea bioactive compounds in developing target cancers. The study reveals that Acmella oleracea has numerous bioactive chemicals advantageous for cancer therapy by inducing apoptosis through interaction with ESR1, MAPK2, and PGR protein.

Assessment of the potential risk of oteseconazole and two other tetrazole antifungals to inhibit adrenal steroidogenesis and peripheral metabolism of corticosteroids.

The triazole antifungals posaconazole and itraconazole can cause pseudohyperaldosteronism with hypertension and hypokalemia, edema, and gynecomastia by inhibiting steroid synthesis and metabolism. Mechanisms underlying pseudohyperaldosteronism include inhibition of adrenal 11β-hydroxylase cytochrome-P450 (CYP) 11B1 and 17α-hydroxylase (CYP17A1) as well as peripherally expressed 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2). To enhance specificity for fungal CYP51, tetrazoles have been developed. This study employed H295R adrenocortical cells and enzyme activity assays to assess the potential risk of oteseconazole and two other tetrazoles, VT-1598 and quilseconazole, to inhibit adrenal steroidogenesis or 11β-HSD2. Steroidomic footprint analyses of H295R cell supernatants using untargeted liquid-chromatography-high-resolution mass-spectrometry (LC-HRMS) indicated overall patterns common to oteseconazole, quilseconazole and itraconazole, as well as similarities between VT-1598 and isavuconazole. Additionally, more specific features of the steroid signatures were observed. Targeted quantification of nine adrenal steroids in supernatants from treated H295R cells revealed an overall inhibition of adrenal steroidogenesis by the three tetrazoles, itraconazole and isavuconazole, providing an explanation for their similar steroidomic pattern. Applying recombinant enzymes indicated that this effect is not due to direct inhibition of steroidogenic enzymes because no or only weak inhibition could be observed. Moreover, oteseconazole and the two other tetrazoles did not inhibit 11β-HSD2, suggesting that they do not pose a risk of pseudohyperaldosteronism. Furthermore, oteseconazole did not alter steroid concentrations in a recent clinical study. Nevertheless, follow-up studies should assess the mechanism underlying the observed overall steroidogenesis inhibition by tetrazoles, itraconazole and isavuconazole, and whether concentrations achievable in a subgroup of susceptible patients might cause adrenal insufficiency and hyperplasia.