bluuebunny/crossref_metadata_2025 huggingface dataset:
8464 A Unique SERM Reveals An Estrogen Receptor-Dependent Secretion Of DKK1 In Breast Cancer Cells
Authors: Young K S , Hancock G , Kregel S , Fanning S W
Published: October 2024

Disclosure: K.S. Young: None. G. Hancock: None. S. Kregel: None. S.W. Fanning: Grant Recipient; Self; Olema Oncology.

Although Estrogen Receptor positive (ER+) breast cancer has been successfully targeted in primary tumors, the critical limitations of hormone therapies are ultimately revealed as many women often experience disease recurrence. A subset of these patients harbor a distinctive tyrosine to serine missense mutation at position 537 (Y537S) in ER leading to allele-specific transcriptional programs that enhance metastasis. ER is a ligand-dependent master transcriptional regulator. Probing unique ER structural features can reveal new transcriptional activities. We developed a structurally unconventional Selective Estrogen Receptor Modulator (SERM), T6I-29, to better understand these structure-transcriptional relationships. T6I-29 shows effective anti-tumoral activities in Y537S ESR1 breast cancer cells. To examine the anti-tumoral mechanism of T6I-29 action, we performed RNA-sequencing on ESR1 Y537S mutant breast cancer cells. Compared to other clinically relevant compounds, our drug uniquely and significantly downregulated DKK1, a tumor secreted protein known to modulate the Wnt/β-Catenin and PI3K/Akt pathways. Upregulation of DKK1 correlates with metastatic burden across multiple cancers but has not been evaluated in ESR1 mutant breast cancers. We find that DKK1 levels are significantly elevated in the plasma of 108 ER+ breast cancer patients compared to 100 matched healthy donors. Furthermore, in wild-type (WT) PIK3CA breast cancer cell lines, those with Y537S ESR1 mutation show constitutive expression and secretion of DKK1, while DKK1 expression and secretion is estrogen-dependent in WT breast cancer cells. Intriguingly, WT cells show significant surface bound DKK1, which is secreted into the media upon hormone stimulation and blocked by T6I-29. Understanding the ER-dependence and functional importance of DKK1 secretion offers a novel approach to potentially reduce breast cancer metastatic burden.

Presentation: 6/3/2024
7409 Estrogen Receptor a (ERa) Signaling Mediates Pro-Tumor Neutrophil Activation In The Setting of Lymphangioleiomyomatosis (LAM)
Authors: Elisabeth O'Leary Katherine , Gibbons Erin , Minor Briaunna M N , Henson Thomas , Hammes Stephen R
Published: October 2024

Disclosure: K.E. O'Leary: None. E. Gibbons: None. B.M. Minor: None. T. Henson: None. S.R. Hammes: None.

Lymphangioleiomyomatosis (LAM), is a rare disease marked by the irregular proliferation of smooth muscle-like cells containing tuberous sclerosis (TSC) gene mutations. The resultant tumor growth causes cyst formation in the lung parenchyma which leads to decline in respiratory function. Notably, LAM almost exclusively affects biological females and appears to be estrogen sensitive. Prior studies have suggested that LAM tumor cells may originate from the uterus, thus explaining the female sexual dimorphism and the estrogen sensitivity. However, recent work from our laboratory suggests that estradiol not only stimulates TSC2-null smooth muscle cells, but also promotes neutrophil production via estrogen receptor α (ERα) signaling in the bone marrow, which in turn stimulates TSC2-null tumor progression. The precise mechanism by which ERα signaling promotes neutrophil production is unknown, nor are the direct effects of ERα signaling in neutrophils well understood; therefore, here we investigated the role of ERα signaling in tumor associated neutrophil activation. We hypothesized that estradiol, in concert with tumor-derived factors, may augment pro-tumorigenic and immunosuppressive functions of neutrophils. To address our hypothesis, Ly6G+ neutrophils were isolated from the harvested bone marrow of both C57BL/6 control and ERα knockout mice. Tumor conditioned media (TCM) containing potential tumor-derived stimulating factors was generated from LTM3 myometrial cells derived from uterine-specific TSC2-null mice (a mouse model for LAM tumors). Isolated neutrophils were then cultured in either fresh cell culture media or TCM for 24 hours. mRNA was collected and real-time quantitative PCR performed to investigate changes in mRNA expression of several known neutrophil activation markers. Our results show ERα was required for full expression of neutrophil elastase (Elane), nitric oxide synthase 2 (Nos2), and programmed death-ligand 1 (Pdl1/Cd274), all markers of neutrophils activated to support tumor progression. In addition, capacity for ERα signaling led to suppression of the chemokine receptor Cxcr2 mRNA. Our results indicate that, in addition to stimulating neutrophil production in bone marrow, estradiol signaling through ERα receptors on neutrophils may have significant influence on the quality of tumor exposed neutrophil activation, promoting a pro-tumorigenic immunosuppressive phenotype.

Presentation: 6/3/2024
12452 Unraveling An Intriguing Clinical Sequence: Thyrotoxicosis Antecedent To Stiff Person Syndrome
Authors: Jain Ashali , Natasha Rayan Melanie
Published: October 2024

Disclosure: A. Jain: None. M.N. Rayan: None.

Background: Stiff Person Syndrome (SPS) is an autoimmune phenomenon resulting in the progressive rigidity of limbs and trunk muscles. It is associated with GAD-positive antibodies in the CSF and serum and is linked to Type 1 Diabetes, Celiac disease, and other autoimmune diseases. Clinical Case: A 34-year-old female with no past medical history was brought into the ED by family for paranoia, suicidal ideations, and visual and auditory hallucinations. She was found to be tachycardic and altered in the ED. Endocrinology was initially consulted for concerns of hyperthyroid pathology due to lab work showing a TSH of <0.008 uIU/mL and free T4 of 4 pg/mL. Thyroid ultrasound revealed heterogeneous, hypervascular thyroid tissue. Further investigation revealed TRAB 4.05 IU/L (n 0-0.9 IU/L) and TSI 3 IU/L (n < 0.577 IU/L). A diagnosis of Graves’ disease was made, and she was started on methimazole 20mg daily and metoprolol 25mg daily. Due to a lack of response to methimazole, other organic causes were investigated including psychiatric and neurological etiology. The patient's symptoms continued to worsen, with new tremors of the upper and lower extremities. Thyroid labs showed improvement, and hence thyrotoxicosis was not thought to be the underlying etiology of her encephalopathy. Neurology was consulted, and EEG and MRI Brain were performed which were unrevealing. Lumbar puncture revealed elevated oligoclonal bands and GAD-65 antibodies, suggesting autoinflammatory encephalitis. High-dose steroids were started, with no improvement. Due to the failure of steroids to treat her symptoms, she was given 5 days of plasmapheresis and a dose of rituximab. Slowly, the patient began to improve and could follow commands and communicate with staff. A formal diagnosis of SPS was made at this time. Upon seeing her in follow-up 1 month after discharge, her TRAB and TSI antibodies were negative, and she was able to be titrated off of methimazole. Conclusion: SPS is strongly associated with autoimmune diseases, with up to 30-40% having T1DM. The association between hyperthyroidism and SPS, however, is exceedingly rare and the etiology remains unclear.

Presentation: 6/1/2024
8464 A Unique SERM Reveals an Estrogen Receptor-Dependent Secretion of DKK1 in Breast Cancer Cells
Authors: Young K S , Hancock G , Kregel S , Fanning S W
Published: October 2024

Disclosure: K.S. Young: None. G. Hancock: None. S. Kregel: None. S.W. Fanning: Grant Recipient; Self; Olema Oncology.

Although Estrogen Receptor positive (ER+) breast cancer has been successfully targeted in primary tumors, the critical limitations of hormone therapies are ultimately revealed as many women often experience disease recurrence. A subset of these patients harbor a distinctive tyrosine to serine missense mutation at position 537 (Y537S) in ER leading to allele-specific transcriptional programs that enhance metastasis. ER is a ligand-dependent master transcriptional regulator. Probing unique ER structural features can reveal new transcriptional activities. We developed a structurally unconventional Selective Estrogen Receptor Modulator (SERM), T6I-29, to better understand these structure-transcriptional relationships. T6I-29 shows effective anti-tumoral activities in Y537S ESR1 breast cancer cells. To examine the anti-tumoral mechanism of T6I-29 action, we performed RNA-sequencing on ESR1 Y537S mutant breast cancer cells. Compared to other clinically relevant compounds, our drug uniquely and significantly downregulated DKK1, a tumor secreted protein known to modulate the Wnt/β-Catenin and PI3K/Akt pathways. Upregulation of DKK1 correlates with metastatic burden across multiple cancers but has not been evaluated in ESR1 mutant breast cancers. We find that DKK1 levels are significantly elevated in the plasma of 108 ER+ breast cancer patients compared to 100 matched healthy donors. Furthermore, in wild-type (WT) PIK3CA breast cancer cell lines, those with Y537S ESR1 mutation show constitutive expression and secretion of DKK1, while DKK1 expression and secretion is estrogen-dependent in WT breast cancer cells. Intriguingly, WT cells show significant surface bound DKK1, which is secreted into the media upon hormone stimulation and blocked by T6I-29. Understanding the ER-dependence and functional importance of DKK1 secretion offers a novel approach to potentially reduce breast cancer metastatic burden.

Presentation: 6/3/2024
9354 Combination Of Novel Ruthenium-based Small Molecule Bold-100 And Capecitabine Is Effective In Inhibiting Growth Of Estrogen Receptor Positive Metastatic Breast Cancer
Authors: Scheidemann Erin R , Demas Diane M , Ashai Nadia , Shajahan-Haq Ayesha N
Published: October 2024

Disclosure: E.R. Scheidemann: None. D.M. Demas: None. N. Ashai: None. A.N. Shajahan-Haq: None.

The most common breast cancer subtype in both women and men is estrogen receptor alpha positive (ER+). In the adjuvant setting, ER+ tumors are initially treated with endocrine therapy that includes antiestrogens. Mechanistically, estrogen triggers a mitogenic signaling cascade through the ER, which activates the cyclin D1-cyclin-dependent kinase 4 and 6 (CDK4/6) complex to promote cell growth. ER+ tumors that progress on antiestrogens are subsequently treated with a combination of antiestrogens and CDK4/6 inhibitors (palbociclib, ribociclib or abemaciclib). However, 20% of ER+ tumors never respond to CDK4/6i due to intrinsic resistance and the tumors that initially respond will develop acquired resistance. In the absence of driver mutations, resistant tumors are treated with standard chemotherapies, including capecitabine, which interferes with DNA synthesis. However, treatment with capecitabine show meager success and accompany adverse side effects. BOLD-100 is a ruthenium-based novel small molecule drug that demonstrated antitumor activity as a monotherapy in a phase I clinical trial with a manageable safety profile at the maximum tolerated dose. BOLD-100 has recently been investigated in a multicenter global Phase 1B/2A trial (NCT04421820) of gastrointestinal cancer patients in combination with chemotherapy FOLFOX, which includes fluorouracil, the active form of capecitabine. Previously, we have shown that in breast cancer cells, treatment with BOLD-100 disrupted proteins involved in DNA repair pathway, stimulated reactive oxygen species (ROS) and induced cell death via interrupting autophagy and inducing apoptosis. In this study, we show that combination of BOLD-100 and capecitabine synergistically inhibits growth of breast cancer cells and tumors that are resistant to CDK4/6 inhibitors. Cells treated with combination of capecitabine and BOLD-100 shows increase in apoptosis and DNA damage compared with cells treated with monotherapies or control. Therefore, capecitabine and BOLD-100 is a potential novel combination therapy for breast cancer that has progressed on standard of care treatment.

Presentation: 6/2/2024
5113 Investigation And Management Of Primary Aldosteronism With Adrenal Vein Sampling At The CHU De Québec-Université Laval
Authors: Boisvert Amélie , Coll Julie-Catherine , Gagnon Nadia , Lamarre Andre
Published: October 2024

Disclosure: A. Boisvert: None. J. Coll: None. N. Gagnon: None. A. Lamarre: None.

Background: Adrenal vein sampling (AVS) is the gold-standard test to assess for lateralization in primary aldosteronism (PA). In case of unsuccessful right adrenal vein (RAV) cannulation, our tertiary care centre (CHU de Québec-UL) uses a multinomial regression model to extrapolate the RAV cannulation results. Objectives: 1) To determine the proportion of successful RAV cannulation during AVS at the CHU de Québec-UL; 2) To evaluate the management and clinical evolution of patients with PA who underwent AVS at the CHU de Québec-UL, including those who were treated based on the multinomial regression model results. Methods: This retrospective cohort study included patients aged ≥18 years with a diagnosis of PA who underwent AVS between January 2017 and September 2022 at the CHU de Québec-UL. Epidemiological data at diagnosis were collected, as well as data on AVS cannulation, AVS complications and PA clinical evolution. Successful RAV cannulation was determined by the interventional radiologist and by cortisol ratios. Results are presented as percentage or mean±SD. Results: 39 patients were included (33,3% women; mean age 51,1±11,5 years; 89,7% with hypertension treated with a mean of 2,5±1,1 antihypertensive drugs; 74,4% with hypokalemia), for a total of 40 AVS procedures. 3 procedures (7,5%) selectively cannulated both adrenal veins. 3 procedures (7,5%) led to complications (subcutaneous hematoma). Of the 33 incomplete AVS procedures, the clinical management after 6 of these procedures was unavailable due to follow-up in other hospital centres. Among the remaining 27 patients, 5 (18,5%) had a second complete AVS in another tertiary care center, 12 (44,4%) were medically treated, 1 (3,7%) had an adrenalectomy and 11 (40,7%) were treated according to the multinomial regression model results. The model lateralized aldosterone secretion in 5 patients, who then all had adrenalectomy, after which 4 were diagnosed adrenal adenomas and one was diagnosed adrenal hyperplasia on pathology. The 8 complete AVS procedures led to 6 diagnoses of unilateral disease and 2 diagnoses of bilateral disease. Applying the multinominal regression model to the initial AVS procedure of these 8 cases would have correctly predict aldosterone lateralization in 7 cases (87,5%). Conclusion: AVS success rate in our tertiary care centre was low. The multinominal regression model appeared to adequately detect unilateral disease in our small sample. It is necessary to reevaluate our AVS technical protocol to increase our AVS successful cannulation rate.

Presentation: 6/1/2024
7409 Estrogen Receptor a (ERa) Signaling Mediates Pro-Tumor Neutrophil Activation in the Setting of Lymphangioleiomyomatosis (LAM)
Authors: Elisabeth O'Leary Katherine , Gibbons Erin , Minor Briaunna M N , Henson Thomas , Hammes Stephen R
Published: October 2024

Disclosure: K.E. O'Leary: None. E. Gibbons: None. B.M. Minor: None. T. Henson: None. S.R. Hammes: None.

Lymphangioleiomyomatosis (LAM), is a rare disease marked by the irregular proliferation of smooth muscle-like cells containing tuberous sclerosis (TSC) gene mutations. The resultant tumor growth causes cyst formation in the lung parenchyma which leads to decline in respiratory function. Notably, LAM almost exclusively affects biological females and appears to be estrogen sensitive. Prior studies have suggested that LAM tumor cells may originate from the uterus, thus explaining the female sexual dimorphism and the estrogen sensitivity. However, recent work from our laboratory suggests that estradiol not only stimulates TSC2-null smooth muscle cells, but also promotes neutrophil production via estrogen receptor α (ERα) signaling in the bone marrow, which in turn stimulates TSC2-null tumor progression. The precise mechanism by which ERα signaling promotes neutrophil production is unknown, nor are the direct effects of ERα signaling in neutrophils well understood; therefore, here we investigated the role of ERα signaling in tumor associated neutrophil activation. We hypothesized that estradiol, in concert with tumor-derived factors, may augment pro-tumorigenic and immunosuppressive functions of neutrophils. To address our hypothesis, Ly6G+ neutrophils were isolated from the harvested bone marrow of both C57BL/6 control and ERα knockout mice. Tumor conditioned media (TCM) containing potential tumor-derived stimulating factors was generated from LTM3 myometrial cells derived from uterine-specific TSC2-null mice (a mouse model for LAM tumors). Isolated neutrophils were then cultured in either fresh cell culture media or TCM for 24 hours. mRNA was collected and real-time quantitative PCR performed to investigate changes in mRNA expression of several known neutrophil activation markers. Our results show ERα was required for full expression of neutrophil elastase (Elane), nitric oxide synthase 2 (Nos2), and programmed death-ligand 1 (Pdl1/Cd274), all markers of neutrophils activated to support tumor progression. In addition, capacity for ERα signaling led to suppression of the chemokine receptor Cxcr2 mRNA. Our results indicate that, in addition to stimulating neutrophil production in bone marrow, estradiol signaling through ERα receptors on neutrophils may have significant influence on the quality of tumor exposed neutrophil activation, promoting a pro-tumorigenic immunosuppressive phenotype.

Presentation: 6/3/2024
8553 Gdf-15 Levels In Patients With Prostate Cancer On Androgen Deprivation Therapy
Authors: Carmen Jaramillo-Quiroz Sofia del , Caeiro Lucas , Jayne Anderson Lindsey , Manuel Garcia Jose
Published: October 2024

Disclosure: S.D. Jaramillo-Quiroz: Other; Self; VAPSHCS: Director Fund Research Fellowship/UW Abrass Family Fellowship Fund. CDMRP (PC170059).. L. Caeiro: None. L.J. Anderson: None. J.M. Garcia: None.

Growth Differentiation Factor 15 (GDF-15) is a stress-induced cytokine known to induce anorexia and cachexia and a biomarker of biological aging, mitochondrial dysfunction, and worse hand grip strength and poor survival in different settings. Also, GDF-15 has pleiotropic functions at all stages of tumorigenicity and is suggested as a marker to differentiate BPH from PCa. Androgen Deprivation Therapy (ADT) is the standard treatment for advanced prostate cancer (PCa), but it also decreases muscle mass and function and Quality of life (QOL). The role and effects of GDF-15 in prostate cancer patients undergoing ADT are not well characterized and was explored in this longitudinal, 6-month, observational study that recruited men with (PCa) starting ADT (n=60, mean age 69). Body composition [dual energy X-ray absorptiometry (DEXA), body weight history], physical performance [handgrip strength (HGS), 6-minute walk test (6MWT), energy expenditure (indirect calorimetry and actigraphy)], were assessed before, at 3 and 6 months after starting ADT. QoL was assessed by the European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire (EORTC-QLQ-C30). GDF-15 was measured by ELISA. Mean differences performed with standard error of the mean, repeated measures ANOVA and Tukey’s Post Hoc test. Correlations were assessed by Spearman’s. After 6 months of ADT, fat mass was increased (mean difference: 1.14 ±0.38, p=0.0029), and lean muscle mass (mean difference: -1.214 ± 0.38, p=0.005), appendicular lean mass (ALM, mean difference: -0.879 ± 0.19, p=<0.0001). HGS (mean difference: -2.927 ± 0.59, p=<0.0001), and VO2 max decreased (mean difference -3.31 ± 0.83, p=0.0007). Baseline GDF-15 (mean 1456.59 ± 1022.80) was correlated with the changes in weight (r: -0.38, p=0.01), BMI (r: -0.33, p=0.01), ALM (r: -0.29, p=0.04), and fatigue (r: -0.38, p=0.004). As shown, baseline GDF-15 was inversely correlated with changes in weight, appendicular lean mass, and fatigue in subjects undergoing ADT, highlighting the possibility of its role as a biomarker and therapeutic target of body composition and patient-reported outcomes in this setting.

Presentation: 6/1/2024
8277 Pregnancy-Induced Cushing Syndrome
Authors: Al Allawi Sarah , Okigbo Chinelo , Osman Radwa
Published: October 2024

Disclosure: S. Al Allawi: None. C. Okigbo: None. R. Osman: None.

Introduction: Pregnancy is uncommon in women with Cushing syndrome (CS), as hypercortisolism typically leads to anovulatory infertility. CS during pregnancy can be challenging due to the physiological changes in the hypothalamic-pituitary-adrenal axis, overlapping features with pregnancy, and the potential for misdiagnosis as gestational diabetes or hypertension. Pregnancy-induced Cushing is rarely reported, and can sometimes completely remit postpartum, although some cases recur with subsequent pregnancies. Here, we describe a case of pregnancy-induced hypercortisolism with postpartum remission. Clinical Case: A 26-year-old primigravida with a reported history of PCOS, presented to the hospital at 25 weeks of gestation due to concerns for pre-eclampsia. Prior to her pregnancy, she had a history of oligomenorrhea and had an intrauterine device (IUD) in place until a month before conception. In the first trimester, she developed severe facial acne and excessive hirsutism. An abdominal MRI obtained due to abdominal pain, revealed an enlarged right ovary with a 4.2 cm dominant cyst and a slight asymmetric prominence of the left adrenal, indicating hyperplasia. At 18 weeks, she was diagnosed with pre-eclampsia and subsequently developed severe hypokalemia and muscle weakness. This prompted a workup for hypercortisolism which revealed elevated morning cortisol level of 55 mcg/dL, elevated 24-hour urinary cortisol 2,282 mcg/24 hr, suppressed ACTH < 5 pg/mL, elevated total testosterone 337 ng/dL and plasma renin activity (8.13 ng/mL/hr) with normal DHEAs and aldosterone levels. Repeat workup showed similar findings. A diagnosis of ACTH-independent Cushing syndrome was made. At 25 weeks, she was admitted for severe pre-eclampsia. Physical exam revealed cushingoid features with facial fullness, plethora, dorsocervical fat pads, generalized violaceous striae, and severe acne. A decision was made to initiate Metyrapone, but the patient quickly developed HELLP syndrome which led to premature delivery at 26 weeks, with a concomitant right ovarian cystectomy. Pathology revealed a benign serous cystadenoma. On Postpartum day 2, workup showed a drop in morning cortisol to 26 mcg/dL, ACTH 4.9 pg/mL, total testosterone 25 ng/dL. Three months postpartum, the patient had an improvement in the cushingoid features. Hormonal reassessment demonstrated morning cortisol of 9 mcg/dL, suppressed ACTH < 5 pg/mL, and total testosterone 47 ng/dL. Conclusion: Cushing's syndrome in pregnancy is rare, leading to a low suspicion among physicians and delayed diagnosis, posing risks for both mother and fetus. Over 260 cases of CS in pregnancy have been reported, with only 15 cases of pregnancy-induced Cushing's. Maintaining a high index of clinical suspicion can facilitate prompt diagnosis and early intervention, thereby minimizing maternal and fetal morbidity and improving pregnancy outcomes.

Presentation: 6/3/2024
6620 Serum Steroid Profiling For The Diagnosis Of Adrenocortical Carcinoma: A Prospective Cross-Sectional Study From A Tertiary Center
Authors: Yu K , Athimulam S , Saini J , Kaur R , Singh R J , Grebe S K , Xue Q , Bancos I
Published: October 2024

Disclosure: K. Yu: None. S. Athimulam: None. J. Saini: None. R. Kaur: None. R.J. Singh: None. S.K. Grebe: None. Q. Xue: None. I. Bancos: Advisory Board Member; Self; AstraZeneca, Corcept, Novo Nordisk, HRA Pharmaceuticals, Neurocrine, Diurnal, Recordati, Sparrow, Xeris, Spruce, Adrenas. Research Investigator; Self; HRA Pharmaceuticals, Recordati.

Context: Early diagnosis is essential to assure a better prognosis in patients with adrenocortical carcinoma (ACC). Guidelines suggested performing urine steroid profiling in patients with indeterminate adrenal tumors to make a noninvasive diagnosis of ACC. However, urine steroid profiling is not widely available. Accuracy of clinically available serum steroids in diagnosing ACC has not been established. Objective: To determine the accuracy of 11-deoxycortisol, 17OH-progesterone, and 17OH-pregnenolone in diagnosing ACC. Design: Prospective single-center cohort study. Participants: Between 2015 and 2023, consecutive patients with adrenal mass were prospectively enrolled in the prospective registry and biobank study. Patients who agreed to contribute a fasting serum sample were included in the study. Exclusion criteria were congenital adrenal hyperplasia, exogenous glucocorticoid use, absence of unenhanced Hounsfield unit measurements (HU), and lack of established reference standard (histopathology, imaging characteristics, 2-year imaging follow up, or 5-year clinical follow up). Measures and Outcomes: measurements included 11-deoxycortisol, 17OH-progesterone, and 17OH-pregnenolone by liquid chromatography–mass spectrometry. Localized Generalized Matrix Learning Vector Quantization (LGMLVQ) analysis was used to develop serum steroid score and assessed with area under receiver operating curve (AUROC). Results: Of 263 patients with adrenal masses, 44 (17%) were diagnosed with ACC, 161 (61%) with adrenocortical adenomas (ACAs), 27 (10%) with other adrenal malignancies, and 31 (12%) with other. HU ≥ 20 were demonstrated in all ACCs, in all but one other adrenal malignancy, and only in 58 (31%) ACAs. All 3 steroids were higher in patients with ACCs vs nonACCs, including when comparing ACCs with functioning ACAs, and with ACAs with HU ≥ 20 (P<0.0001 for all). LGMLVQ analysis yielded a serum steroid score that discriminated between ACC and non-ACC groups with a mean threshold fixed AUROC of 0.823. Serum steroid score of 0.29 demonstrated a mean false negative rate of 0% and a score of 0.61 demonstrated a mean false positive rate of 0%. Conclusions: We showed that measurements of 11-deoxycortisol, 17OH-progesterone, and 17OH-pregnenolone could be valuable in diagnosing ACC. After appropriate validation, serum steroid score could be integrated in clinical practice.

Presentation: 6/2/2024
12515 Single-Nuclei Multiome Analysis Of The Adrenal Gland Identifies Putative Novel Regulators Of Zone-Specific Steroidogenesis
Authors: Marcondes Lerario Antonio , Rege Juilee , Blinder Amy , Hammer Gary D , Rainey William E
Published: October 2024

Disclosure: A.M. Lerario: None. J. Rege: None. A. Blinder: None. G.D. Hammer: None. W.E. Rainey: None.

The human adrenal cortex comprises three distinct histological zones: the outer zona glomerulosa (ZG), responsible for aldosterone production, the middle zona fasciculata (ZF), producing cortisol, and the inner zona reticularis (ZR), contributing to the synthesis of DHEAS. One key mechanism of zone-specific steroidogenesis lies in the selective expression of membrane receptors for the endocrine regulators AngII and ACTH in the ZG and ZF/ZR, respectively. Activation of these receptors drives zone-specific expression of CYP11B2, CYP11B1, and SULT2A1, the steroidogenic enzymes responsible for the final step of aldosterone, cortisol, and DHEAS biosynthesis, respectively. While the downstream intracellular signaling pathways governing the expression of these enzymes are well characterized, the transcriptional regulatory mechanisms remain incompletely understood. To identify potential transcriptional regulators and chromatin regions controlling the zone-specific expression of steroidogenic enzymes, we conducted a single-nuclei multiome study (RNAseq and ATACseq) in three adrenal glands from adult kidney donors with normal zonation confirmed by immunohistochemistry. As expected, our analysis revealed distinct cell populations with gene expression profiles characteristic of each histological zone, displaying zone-specific expression patterns of CYP11B2, CYP11B1, and SULT2A1. Furthermore, within each zone, subpopulations of cells exhibited variable expression of steroidogenic enzymes, indicative of diverse states of differentiation or cellular activation. Moreover, we identified zone-specific changes in chromatin accessibility spanning the promoters and putative distal regulatory regions of CYP11B2, CYP11B1, and SULT2A1. Transcription factor binding motif analysis of these regions identified known and potentially novel transcriptional regulators controlling the expression of these genes. Our analyses underscore the complexity of the regulatory network that controls the transcription of zone-specific steroidogenic enzymes, highlighting the interplay between promoter-bound transcriptional regulators and distal cis-regulatory elements.

Presentation: 6/2/2024
12444 Steroid Profiling And Circadian Cortisol Secretion In Patients With Mild Autonomous Cortisol Secretion: A Single-Center Cross-Sectional Study
Authors: Saini Jasmine , Singh Sumitabh , Ladefoged Ebbehøj Andreas , Zhang Catherine D , Nathani Rohit , Fell Vanessa , Atkinson Elizabeth , Achenbach Sara , Rivard Ann , Jit Singh Ravinder , Gunther Grebe Stefan Karl , Bancos Irina
Published: October 2024

Disclosure: J. Saini: None. S. Singh: None. A.L. Ebbehøj: None. C.D. Zhang: None. R. Nathani: None. V. Fell: None. E. Atkinson: None. S. Achenbach: None. A. Rivard: None. R.J. Singh: None. S.K. Grebe: None. I. Bancos: None.

Abstract Context: Mild autonomous cortisol secretion (MACS) is diagnosed based on post-dexamethasone cortisol>1.8 mcg/dL. Scarce evidence exists on steroid circadian secretion and steroid metabolome in MACS. Objective: To characterize 24-hour urine steroid metabolome in patients with MACS and determine circadian differences in urine steroid profiling and cortisol concentrations in patients with MACS versus referent subjects. Design: Cross-sectional study, 2018-2023. Setting: Referral center Participants: 72 patients with MACS and 72 age-, sex-, BMI-, and menopausal status-matched referent subjects. Measurements: Urine was collected over a 24-hour (h) period in separate day- and night-time collections. High-resolution mass spectrometry assay was used to measure 25 steroids. A subgroup of patients and referent subjects were admitted for every 2-hour serum measurement of free and total cortisol. Outcomes: Steroids, sums, and ratios Results: Patients with MACS had lower mcg/24h median androgens (2084 vs 3283, P<0.001), higher glucocorticoids (15754 vs 12936, P<0.001), and higher glucocorticoid/androgen ratio (8.7 vs 3.9, P<0.001). Steroid day/night ratios were lower in patients when compared to referent subjects, reflecting a higher relative nocturnal steroid production in MACS. In a subgroup of 12 patients with MACS and 10 referent subjects, the 24-hour area under the curves for total and free cortisol were similar. However, nocturnal mean total (5.3 vs 4.0 mcg/dL, P=0.056) and free (0.2 vs 0.1 mcg/dL, P=0.035) cortisol were higher in patients vs referent subjects. Conclusion: Patients with MACS demonstrate an abnormal urine steroid metabolome, with a high glucocorticoid to androgen ratio, and a higher nocturnal steroid production.

Presentation: 6/3/2024
7325 Adjuvant Denosumab Therapy For Adult-Onset Central Giant Cell Granuloma
Authors: Khalid S , Whitlatch H
Published: October 2024

Disclosure: S. Khalid: None. H. Whitlatch: None.

Introduction: Central giant cell granulomas (CGCG) are rare, expansile non-neoplastic bone lesions involving the mandible or maxilla. These lesions consist of a mix of mononuclear and multinucleated giant cells in a mesenchymal stromal background. CGCG typically occurs before the age of 20 years and is more common in females. Conventionally, surgery has been the mainstay of treatment, ranging from curettage to aggressive resection. Unfortunately, curettage is associated with a recurrence rate of up to 49%. While surgical resection lowers recurrence rate to 6%, it can be associated with substantial morbidity, especially with larger lesions. This has led to the investigational use of medical adjunctive therapy, including intralesional corticosteroids, bisphosphonates, and calcitonin. Recently, there have been case reports involving the successful use of denosumab, a monoclonal antibody to receptor activator of nuclear factor-ΚB ligand (RANK-L). Here, we describe an unusual case of adult-onset CGCG treated with surgery and denosumab. CASE: A 24-year-old female presented to the oral maxillofacial surgery clinic with progressive left-sided mandibular swelling of 2 years duration. On examination, she was noted to have left lower third facial swelling and asymmetry. Intraoral exam showed buccal and labial expansion extending from tooth 19 to 27. CT scan revealed a large, multiloculated, expansile lytic lesion of the left mandible measuring up to 4.2 cm. Biopsy of the lesion was rich in giant cells, and the appearance favored giant cell granuloma. Biochemical evaluation included PTH 29 mg/dL (normal 15 mg/dL - 65 mg/dL), calcium 9.2 mg/dL (8.7 mg/dL -10.2 mg/dL), phosphorus 4.7 mg/dL (3 mg/dL -4.4 mg/dL) and alkaline phosphatase 94 mg/dL (44 mg/dL -121 mg/dL). She underwent enucleation and curettage of the lesion. 3 months after the surgery, she started her course of denosumab 120 mg weekly for 4 weeks, followed by monthly dosing with planned 1 year course. She noted improvement in pain after 2 doses of denosumab, and x-ray imaging at 1 month showed improved bone fill. Conclusion: Denosumab exerts its therapeutic effect in giant cell lesions by inhibiting osteoclast maturation, thereby suppressing osteolysis and giant cell formation. Our case suggests it could be considered first line adjuvant treatment for patients with large CGCG lesions.

Presentation: 6/2/2024
8056 Burosumab Treatment In McCune Albright Syndrome: New Therapeutic Perspectives And Gaps To Be Filled
Authors: Barbato A , Vaiasuso R , Del Medico G , Stagi S
Published: October 2024

Disclosure: A. Barbato: None. R. Vaiasuso: None. G. Del Medico: None. S. Stagi: None.

Background: McCune Albright syndrome (MAS) is a sporadic genetic condition associated with bone dysplasia, multiple endocrine over-function, and café au lait skin macules. It is caused by postzygotic mosaic activating mutations of GNAS gene located on chromosome 20q13.3, leading to increased activity of Gs α protein. Fibrous dysplasia (FD) is one of the key features of this syndrome and causes bone deformities with pathologic fractures. In pediatric age, therapies for FD are only able to control pain and reduce burden of disability but not to modify the course of the disease. FGF23 production is increased in MAS and negatively influences bone metabolism. Anti-FGF23 antibody, burosumab, has been recently introduced as a potential new treatment for FD. Case presentation: an 11 years old boy with MAS was referred to our Center for periodic follow-up and treatment of severe FD. He was diagnosed with FD at the age of 1 year and 8 months and since then underwent 4 pathological fractures and 2 surgical interventions for correction of bone deformity. At the age of 6 years old subclinical hyperthyroidism was diagnosed. At the same age he started treatment with endovenous neridronate every three months with partial control of the pain but progression of bone deformity. One year later he developed hypophosphatemia (nadir 3.1 mg/dl) with increased FGF23 levels (144 pg/ml). Because of the clinical worsening of the disease with persistent laboratory alterations (phosphate 3.1 mg/dl, FGF23 251 pg/ml, alkaline phosphatase (ALP) 2188 UI/l, 25-OH vitamin D 58 ng/ml, and PTH 38 pg/ml), at 9 years old he started periodic treatment with burosumab (0.4 mg/kg). The same year the patient developed a central precocious puberty therefore treatment with GnRH was started. After 1 year of treatment with burosumab (0,8 mg/kg) we observed an increase in phosphate levels to 4.2 mg/dl and a reduction of ALP to 1490 UI/L while FGF23 remained stable 243 pg/ml, as did 25 OH vitamin D 31 ng/ml, and PTH 44 pg/ml. At periodic X-rays we documented a slower but still present progression of the FD. Conclusion: burosumab showed beneficial effect on bone tissue metabolism in our patient without significant adverse reactions but did not manage to completely stop FD progression and reduce FGF23 levels. This finding highlights how FGF23 acts as exacerbating factor rather than sole determinat of FD, leading to only a partial clinical response to anti-FGF23 therapy. Furthermore, the presence of FD reduces the efficacy of ALP as a marker of laboratory response, requiring a more disease specific approach to laboratory monitoring of response to burosumab in MAS. New target therapies are needed for Gs α over-function.

Presentation: 6/1/2024
7390 Case Study Of New Lesion Formation In FOP Patients By 18F-NaF PET/CT Imaging
Authors: Trotter D Gonzalez , Srinivasan D , Mohammadi K , Economides A N , Herman G , Mellis S
Published: October 2024

Disclosure: D. Gonzalez Trotter: Employee; Self; Regeneron Pharmaceuticals. Stock Owner; Self; Regeneron Pharmaceuticals. D. Srinivasan: Employee; Self; Regeneron Pharmaceuticals. Stock Owner; Self; Regeneron Pharmaceuticals. K. Mohammadi: Employee; Self; Regeneron Pharmaceuticals. Stock Owner; Self; Regeneron Pharmaceuticals. A.N. Economides: Employee; Self; Regeneron Pharmaceuticals. Stock Owner; Self; Regeneron Pharmaceuticals. G. Herman: Employee; Self; Regeneron Pharmaceuticals. Stock Owner; Self; Regeneron Pharmaceuticals. S. Mellis: Employee; Self; Regeneron Pharmaceuticals. Stock Owner; Self; Regeneron Pharmaceuticals.

Fibrodysplasia ossificans progressiva (FOP) is an ultra-rare disorder characterized by the deposition of bone in soft tissues, known as heterotopic ossification (HO). The formation of HO lesions is sporadic and is sometimes associated with painful swellings (flares), which subside over time. LUMINA-1, a phase 2, randomized, double-blind study (NCT03188666), evaluated the safety and efficacy of garetosmab, an anti-activin A antibody, versus placebo in adult patients with FOP. This case series uses [1]8F-NaF PET/CT imaging to follow the evolution of new HO lesions in placebo-treated patients during the double-blinded period of the study, during which patients were imaged at baseline, Week 8, and Week 28 from randomization. Six patients were selected to represent the observed range of aggregate positive new lesion volume burden. Lesion characteristics over time were reported according to their number, time of initial observation, location, and size. A total of 21 new lesions were detected: three appearing at Week 8 and 18 appearing at Week 28. Individual patients accumulated nine (left shoulder, humerus, and scapula), two (left femur and forearm), one (left pelvis), four (right thigh), three (right thigh), and two (right tibia) new lesions by Week 28, with an aggregate volume of 84.8, 36.0, 14.7, 14.5, 3.2, and 1.1 cm3, respectively. All three lesions that were first observed at Week 8 were detected at Week 28 and had increased in size by an average of 277% (10.0 cm3). This case series illustrates the tendency of new lesions to appear in clusters at disparate locations, with those initially observed at Week 8 persisting into Week 28. These findings suggest that after their initial formation new HO lesions generally do not regress spontaneously, indicating the need for therapeutic interventions that inhibit the initial formation of new HO lesions in FOP patients.

Presentation: 6/2/2024
7253 Changes In Bone Density Observed After Transitioning From Denosumab To Alendronate Or Zoledronic Acid
Authors: Khan Aysha , Prakash Ramchandani Bhanvi , Anne Zielinski Rachel , Liu Jiarui , Sardar Mirza Faryal
Published: October 2024

Disclosure: A. Khan: None. B.P. Ramchandani: None. R.A. Zielinski: None. J. Liu: None. F.S. Mirza: None.

Introduction: Discontinuation of denosumab (Dmab) results in rebound increase in bone turnover and increased risk of vertebral fracture. Guidelines recommend that discontinuation of denosumab should be followed by an oral or intravenous bisphosphonate (BP), hormone therapy or selective estrogen receptor modulator (SERM). Hypothesis: We hypothesize that patients who received weekly alendronate (ALEN) after discontinuation of Dmab will have less of a decline in bone mineral density (BMD) compared to patients who received once yearly zoledronic acid (ZA). Methods: We conducted a retrospective chart review to compare the change in BMD and factors affecting BMD loss in patients who received sequential therapy with ZA versus ALEN. IRB approval was obtained. Patients were selected using Epic SlicerDicer if they had taken Dmab therapy from 2018 (year of epic implementation) onwards and had been transitioned to a BP. A total of 251 patients were initially selected. 35 patients met the inclusion criteria of being transitioned off to ALEN or ZA at least 1 year prior to date of data acquisition; 21 transitioned to ZA and 14 to ALEN. The rest of the patients were continuing Dmab and excluded from the analysis. BMD gain after Dmab therapy was evaluated. BMD change after 1 year of receiving sequential therapy was compared between the two groups at the lumbar spine (LS), femoral neck (FN), and total hip (TH). Results: A total of 35 patients were included in data analysis with mean age of 73.7 + 9 years. The mean percentage gain in BMD achieved after Dmab therapy was 9.9 + 8.5%, 4.6 + 10.6%, and 6 + 5.2% at the LS, FN and TH respectively. The mean duration of Dmab therapy was 4.4 + 2.1 years. One year following sequential therapy, mean percentage BMD loss at the LS was 4.5% with ALEN and 3.0% with ZA (p-value: 0.59, 95% CI: -0.04 to 0.08). Following sequential therapy, mean percentage loss at FN was 2.2% with ALEN and 0.2% with ZA (p-value: 0.1895% CI: (-0.01 to 0.04), mean percentage loss at TH was 2.0 % with ALEN and 2.2% with ZA (p-value: 0.78, 95% CI: -0.03 to 0.02). Mean vitamin D level of all patients at time of starting sequential therapy was 45.9 + 12.9 ng/ml. Duration of prior bisphosphonate use before starting Dmab therapy did not have any significant effect on BMD loss after sequential therapy. All patients had vitamin D level in a good range at the beginning and end of the study period. Conclusion: There is invariably some decline in BMD when transitioning from Dmab to BPs. Although our data showed somewhat greater BMD loss at LS and FN with ALEN compared to ZA, this difference was not statistically significant and failed to reject the null hypothesis. These findings need to be evaluated further in larger prospective studies.

Presentation: 6/3/2024
6634 Dual-Mediated PTH And Osteolytic Hypercalcemia In Metastatic Endometrial Carcinoma
Authors: Persaud Christine K , Beckman Darrick J
Published: October 2024

Disclosure: C.K. Persaud: None. D.J. Beckman: None.

Background: Hypercalcemia of malignancy occurs in 20-30% of advanced stage cancer patients. Etiologies include parathyroid hormone-related peptides (PTHrP)-mediated, osteolytic metastases-mediated, overproduction of 1,25-dihydroxycholecalciferol, and rarely parathyroid hormone (PTH)-mediated. PTH-mediated hypercalcemia of malignancy is rare and occurs through ectopic PTH production or primary hyperparathyroidism. We report a rare case of both PTH-mediated and osteolytic-mediated hypercalcemia in the setting of malignancy. Clinical Case: A 57-year-old female with history of endometrial cancer and multiple solid organ metastasis, presented with two weeks of progressive poor oral intake, nausea, emesis, and right flank pain. On hospital admission, she had a serum calcium of >20.1 mg/dL (8.6-10.2), PTH of 203 pg/mL (15.0-65.0), and creatinine of 1.7 mg/dL (0.7-1.2, baseline 1.3). Non-contrasted CT chest/abdomen/pelvis noted increased size of known right adrenal metastasis, new left adrenal metastasis, periaortic lymphadenopathy, and scattered nodules in the subcutaneous tissues of the abdomen and chest, however bone metastasis were not noted. Patient’s hypercalcemia was treated with zoledronic acid, calcitonin, cinacalcet, and eventually denosumab due to difficulty controlling hypercalcemia. Additional labs obtained during evaluation included ionized calcium >2.5 nmol/L (1.12-1.32), PTHrP <2.0 pmol/L (<2.0), 1,25-dihydroxycholecalciferol <10 pg/mL (21-65). Patient’s right adrenal metastasis biopsy one month prior to admission was subsequently stained for PTH and was negative. Technetium-99m sestamibi scan was obtained for localization of parathyroid adenoma or carcinoma. The scan did not localize, however did show numerous new lytic lesions in the skull, spine, sternum, rib cage, and right humerus. Patient’s hospital course was complicated by progressively worsening renal function, anemia, and thrombocytopenia. Patient was discharged to a long-term acute rehab facility off hypercalcemia treatment with a corrected calcium of 10.0 mg/dL. Conclusion: PTH-mediated hypercalcemia is a rare cause of hypercalcemia of malignancy. PTH levels are typically low or low-normal in osteolytic mediated hypercalcemia. Generally, if PTH is elevated in hypercalcemia, an alternate etiology is not evaluated. This case highlights a rare dual-mediated hypercalcemia of malignancy. The patient’s PTH level elevation was discordant with her high degree of hypercalcemia and prolonged treatment course. She was subsequently found to have widespread bone metastases contributing to hypercalcemia. While multiple etiologies of hypercalcemia can be rare, it is important to evaluate for all contributing causes, especially with additional clinical conditions, such as malignancy.

Presentation: 6/3/2024