Molecular Profiling Research Articles

Distinct clinical profiles and patient outcomes in aCML and CNL.

The classification of atypical chronic myeloid leukemia (aCML) and chronic neutrophilic leukemia (CNL) as a single disease entity remains a topic of debate. To elucidate the characteristics of both entities, this retrospective cohort study was conducted, encompassing 36 cases of aCML and 18 cases of CNL. We discovered that aCML and CNL presented distinct blood counts, genetics, molecular profiles and outcomes. Specifically, hemoglobin levels (P < 0.001) and platelet counts (P < 0.001) were significantly lower in aCML cases than in CNL cases, with no significant difference in mean white blood cells (P = 0.637). The proportion of abnormal karyotypes was higher in aCML cases compared with CNL cases (P = 0.010). Notably, we found that aCML and CNL showed distinct gene expression profiles by transcriptome sequencing technology. The median follow-up duration for the entire cohort was 8months (rang 0.4 to 36.6months), and the median overall survival (OS) was significantly shorter in aCML cases (7.3months, 95%CI 5.4 to 20.5months) than in CNL cases (median OS not reached). The one-year OS rate for aCML patients was 31.0% (9/29), compared to 92.9% (13/14) for CNL patients. In conclusion, our study supports the notion that aCML and CNL are indeed distinct disease entities characterized by unique hematological features and clinical outcomes.

Descriptive Analysis of Common Fusion Mutations in Papillary Thyroid Carcinoma in Hungary

Thyroid cancer is the most common type of endocrine malignancy. Papillary thyroid carcinoma (PTC) is its predominant subtype, which is responsible for the vast majority of cases. It is true that PTC is a malignant tumor with a very good prognosis due to effective primary therapeutic approaches such as thyroidectomy and radioiodine (RAI) therapy. However, we are often required to indicate second-line treatments to eradicate the tumor properly. In these scenarios, molecular therapies are promising alternatives, especially if specifically targetable mutations are present. Many of these targetable gene alterations originate from gene fusions, which can be found using molecular diagnostics like next-generation sequencing (NGS). Nonetheless, molecular profiling is far from being a routine procedure in the initial phase of PTC diagnostics. As a result, the mutation status, except for BRAF V600E mutation, is not included in risk classification algorithms either. This study aims to provide a comprehensive analysis of fusion mutations in PTC and their associations with clinicopathological variables in order to underscore certain clinical settings when molecular diagnostics should be considered earlier, and to demonstrate yet unknown molecular–clinicopathological connections. We conducted a retrospective fusion mutation screening in formalin-fixed paraffin-embedded (FFPE) PTC tissue samples of 100 patients. After quality evaluation by an expert pathologist, RNA isolation was performed, and then NGS was applied to detect 23 relevant gene fusions in the tumor samples. Clinicopathological data were collected from medical and histological records. To obtain the most associations from the multivariate dataset, we used the d-correlation method for our principal component analysis (PCA). Further statistical analyses, including Chi-square tests and logistic regressions, were performed to identify additional significant correlations within certain subsets of the data. Fusion mutations were identified in 27% of the PTC samples, involving nine distinct genes: RET, NTRK3, CCDC6, ETV6, MET, ALK, NCOA4, EML4, and SQSTM1. RET and CCDC6 fusions were associated with type of thyroidectomy, RAI therapy, smaller tumor size, and history of Hashimoto’s disease. NCOA4 fusion correlated with sex, multifocality, microcarcinoma character, history of goiter, and obstructive pulmonary disease. EML4 fusion was also linked with surgical procedure type and smaller tumor size, as well as the history of hypothyroidism. SQSTM1 fusion was associated with multifocality and a medical history of thyroid/parathyroid adenoma. NTRK3 and ETV6 fusions showed significant associations with Hashimoto’s disease, and ETV6, also with endometriosis. Moreover, fusion mutations were linked to younger age at the time of diagnosis, particularly the fusion of ETV6. The frequent occurrence of fusion mutations and their associations with certain clinicopathological metrics highlight the importance of integrating molecular profiling into routine PTC management. Early detection of fusion mutations can inform surgical decisions and therapeutic strategies, potentially improving clinical outcomes.

High increase of Nichols-like clade circulating Treponema pallidum subsp. pallidum in Barcelona from 2021 to 2023.

Worldwide, more than 90% of contemporary syphilis strains belong to SS14-like clade. This study aimed to describe the molecular profile of circulating Treponema pallidum subsp. pallidum (TPA) strains in Barcelona, Spain, from 2021 to 2023 building upon our report in 2015 which showed that 94.8% of typed strains belonged to the SS14 clade. Multilocus sequence typing (MLST) was conducted on TPA-positive samples obtained from swab samples by sequencing the tp0136, tp0548, and tp0705 loci. Strains were classified as Nichols-like or SS14-like clade. Macrolide and tetracycline resistance‑associated mutations were determined through analysis of 23S rDNA and 16S rRNA gene sequences. Of the 96 typeable samples, 47.9% belonged to SS14-like and 52.1% to the Nichols-like. Fourteen haplotypes were identified, with ST26 representing 43.8% of the samples, distributed across 11 haplotypes in the SS14-like and 3 haplotypes in the Nichols-like. All the samples showed macrolide resistance-associated mutations, while none exhibited tetracycline-associated mutations. Our findings revealed a substantial shift in the proportion of TPA clades within the Barcelona population from 2021 to 2023, characterized by a higher proportion of Nichols-like strains compared to 2015 and international trends. The varying temporal and geographical trends underscore the need for regular surveillance to understand regional variations in syphilis and strengthen control programs.

Myelination potential and injury susceptibility of grey versus white matter human oligodendrocytes.

Increasing evidence indicates heterogeneity in functional and molecular properties of oligodendrocyte lineage cells both during development and under pathologic conditions. In multiple sclerosis, remyelination of grey matter lesions exceeds that in white matter. Here we used cells derived from grey matter versus white matter regions of surgically resected human brain tissue samples, to compare the capacities of human A2B5-positive progenitor cells and mature oligodendrocytes to ensheath synthetic nanofibers, and relate differences to the molecular profiles of these cells. For both cell types, the percentage of ensheathing cells was greater for grey matter versus white matter cells. For both grey matter and white matter samples, the percentage of cells ensheathing nanofibers was greater for A2B5-positive cells versus mature oligodendrocytes. Grey matter A2B5-positive cells were more susceptible than white matter A2B5-positive cells to injury induced by metabolic insults. Bulk RNA sequencing indicated that separation by cell type (A2B5-positive vs mature oligodendrocytes) is more significant than by region but segregation for each cell type by region is apparent. Molecular features of grey matter versus white matter derived A2B5-positive and mature oligodendrocytes were lower expression of mature oligodendrocyte genes and increased expression of early oligodendrocyte lineage genes. Genes and pathways with increased expression in grey matter derived cells with relevance for myelination included those related to responses to external environment, cell-cell communication, cell migration, and cell adhesion. Immune and cell death related genes were up-regulated in grey matter derived cells. We observed a significant number of up-regulated genes shared between the stress/injury and myelination processes, providing a basis for these features. In contrast to oligodendrocyte lineage cells, no functional or molecular heterogeneity was detected in microglia maintained in vitro, likely reflecting the plasticity of these cells ex vivo. The combined functional and molecular data indicate that grey matter human oligodendrocytes have increased intrinsic capacity to myelinate but also increased injury susceptibility, in part reflecting their being at a stage earlier in the oligodendrocyte lineage.

Identifying patient subgroups in MASLD and MASH-associated fibrosis: molecular profiles and implications for drug development

The incidence of MASLD and MASH-associated fibrosis is rapidly increasing worldwide. Drug therapy is hampered by large patient variability and partial representation of human MASH fibrosis in preclinical models. Here, we investigated the mechanisms underlying patient heterogeneity using a discovery dataset and validated in distinct human transcriptomic datasets, to improve patient stratification and translation into subgroup specific patterns. Patient stratification was performed using weighted gene co-expression network analysis (WGCNA) in a large public transcriptomic discovery dataset (n = 216). Differential expression analysis was performed using DESeq2 to obtain differentially expressed genes (DEGs). Ingenuity Pathway analysis was used for functional annotation. The discovery dataset showed relevant fibrosis-related mechanisms representative of disease heterogeneity. Biological complexity embedded in genes signature was used to stratify discovery dataset into six subgroups of various sizes. Of note, subgroup-specific DEGs show differences in directionality in canonical pathways (e.g. Collagen biosynthesis, cytokine signaling) across subgroups. Finally, a multiclass classification model was trained and validated in two datasets. In summary, our work shows a potential alternative for patient population stratification based on heterogeneity in MASLD-MASH mechanisms. Future research is warranted to further characterize patient subgroups and identify protein targets for virtual screening and/or in vitro validation in preclinical models.

Extracellular Vesicle Characteristics in Local Fluid and Plasma Measured by Nanoparticle Tracking Analysis Can Help Differentiate High-Grade Serous Carcinoma from Benign Ovarian Pathology

Background: High-grade serous carcinoma (HGSC) is the most lethal of gynecological cancers in developed countries. It usually presents late with non-specific symptoms and most cases are diagnosed at an advanced stage, with 5-year overall survival being around 40%. Biomarkers for screening and early diagnosis of this aggressive disease are, thus, a research priority. Extracellular vesicles (EVs) that reflect the cell of origin and that can be isolated from local fluid and plasma by minimally invasive liquid biopsy are such promising biomarkers. Besides EV concentration and molecular profile, which have been the main focus of research for many years, recent studies have also called attention to EV size distribution. The aim of our study was to evaluate the potential of EV concentration and size distribution in local fluid and plasma as diagnostic biomarkers for HGSC. Methods: Paired pretreatment ascites and plasma samples from 37 patients with advanced HGSC and paired pretreatment free peritoneal fluid (FPF) and plasma samples from 40 controls with benign ovarian pathology (BOP) were analyzed using nanoparticle tracking analysis (NTA). Results: We observed a significant difference in EV concentration in local fluid, but not in plasma, between HGSC patients and the control group. We also found a significant difference in EV size distribution in both local fluid and plasma between HGSC patients and the control group. The receiver operating characteristics (ROC) curve analysis of EV characteristics showed excellent diagnostic performance for the mode, D10, and D50 in local fluid and acceptable diagnostic performance for EV concentration and mean EV size in local fluid, as well as for the mode and D10 value in plasma. Conclusions: The results of our study show that EV concentration in local fluid and more importantly EV size distribution in both local fluid and plasma are significantly changed in the presence of HGSC. Future research of size-dependent molecular profiling of EVs could help identify novel diagnostic biomarkers for HGSC.

MYC-rearranged mature B-cell lymphomas in children and young adults are molecularly Burkitt Lymphoma

Aggressive B-cell non-Hodgkin lymphomas (NHL) in children, adolescents, and young adults (CAYA) include Burkitt lymphoma (BL), diffuse large B-cell lymphoma (DLBCL), and a subset of high-grade tumors with features intermediate between these entities whose genetic and molecular profiles have not been completely elucidated. In this study, we have characterized 37 aggressive B-NHL in CAYA, 33 with high-grade morphology, and 4 DLBCL with MYC rearrangement (MYC-R), using targeted next-generation sequencing and the aggressive lymphoma gene expression germinal center B-cell-like (GCB), activated B-cell-like (ABC), and dark zone signatures (DZsig). Twenty-two tumors had MYC-R without BCL2 breaks, and two MYC-non-R cases had BCL6 translocations. MYC-R cases, including DLBCL, carried BL-related mutations and copy number alterations. Conversely, MYC-non-R lymphomas had alterations in the B-cell receptor signaling/NF-κB pathway (71%). DZsig was expressed in 12/13 of MYC-R tumors but only in 2/10 of MYC-non-R GCB tumors (P < 0.001). The 3-year event-free survival (EFS) of the whole cohort was 79.6%. TP53 and KMT2C mutations conferred inferior outcome (3-year EFS P < 0.05). Overall, MYC-R lymphomas in CAYA have a molecular profile similar to BL regardless of their high-grade or DLBCL morphology, whereas MYC-non-R has more heterogeneous genetic alterations closer to that of DLBCL.

The Hunchback temporal transcription factor determines interneuron molecular identity, morphology, and presynapse targeting in the Drosophila NB5-2 lineage.

Interneuron diversity within the central nervous system (CNS) is essential for proper circuit assembly. Functional interneurons must integrate multiple features, including combinatorial transcription factor (TF) expression, axon/dendrite morphology, and connectivity to properly specify interneuronal identity. Yet, how these different interneuron properties are coordinately regulated remains unclear. Here we used the Drosophila neural progenitor, NB5-2, known to generate late-born interneurons in a proprioceptive circuit, to determine if the early-born temporal transcription factor (TTF), Hunchback (Hb), specifies early-born interneuron identity, including molecular profile , axon/dendrite morphology , and presynapse targeting . We found that prolonged Hb expression in NB5-2 increases the number of neurons expressing early-born TFs (Nervy, Nkx6, and Dbx) at the expense of late-born TFs (Runt and Zfh2); thus, Hb is sufficient to promote interneuron molecular identity. Hb is also sufficient to transform late-born neuronal morphology to early-born neuronal morphology. Furthermore, prolonged Hb promotes the relocation of late-born neuronal presynapses to early-born neuronal presynapse neuropil locations, consistent with a change in interneuron connectivity. Finally, we found that prolonged Hb expression led to defects in proprioceptive behavior, consistent with a failure to properly specify late-born interneurons in the proprioceptive circuit. We conclude that the Hb TTF is sufficient to specify multiple aspects of early-born interneuron identity, as well as disrupt late-born proprioceptive neuron function.

Characterization of Candida species isolated from clinical specimens: insights into virulence traits, antifungal resistance and molecular profiles

BackgroundCandida species have emerged as a significant cause of opportunistic infections. Alongside the expression of various virulence factors, the rise of antifungal resistance among Candida species presents a considerable clinical challenge.AimThis study aimed to identify different Candida species isolated from clinical specimens, evaluate their antifungal sensitivity patterns, identify key genes regulating virulence mechanisms using multiplex PCR and to assess any correlation between their virulence profiles and antifungal resistance patterns.MethodA total of 100 Candida spp. was isolated from 630 different clinical specimens and identified to the species level. Their antifungal susceptibility was phenotypically evaluated in accordance with CLSI guidelines using the Vitek-2 Compact System. Virulence markers, including biofilm formation capacity, protease production, melanin production, coagulase production and hemolysin production, were also phenotypically detected. The genetic determinants for biofilm formation and extracellular hydrolytic enzymes were assessed using a multiplex PCR assay.ResultsThe prevalence of Candida spp. was 15.9%, with C. albicans (48%) and C. glabrata (16%) being the most common. C. albicans showed the highest virulence, with strong biofilm formation, and high proteinase and melanin production. Multiplex PCR revealed Hlp in 22.0%, Hwp in 80.0%, Als in 56.0%, and Sap genes in 56.0% of isolates. Virulence genes were more common in C. albicans than in non-albicans Candida (NAC). Resistance patterns significantly correlated with virulence profiles, with notable associations between flucytosine resistance and the presence of Hlp and Hwp genes.ConclusionThe significant correlation between virulent markers such as germination, coagulase, hemolysin production and resistance patterns among different Candida isolates is crucial for predicting the severity and outcomes of Candida infections. This understanding aids in guiding tailored treatment strategies.

Clinicopathological and molecular genetic insights into EBV-positive inflammatory follicular dendritic cell sarcoma

Epstein-Barr virus (EBV)-positive inflammatory follicular dendritic cell (FDC) sarcoma (EBV + IFDCS) is a rare entity, and its histopathological characteristics have not been fully described. This study aimed to investigate the clinical characteristics, pathological features, and molecular genetic profiles of EBV + IFDCS to improve our understanding of these lesions. A total of 12 EBV + IFDCS specimens were obtained from patients in our pathology diagnostic center. The clinical data, morphology, immunohistochemistry, in situ hybridization, and high-throughput DNA-targeted sequencing data were collected, and follow-up data were analyzed. These data were compared with those of 6 patients with traditional FDCS. The patients with EBV + IFDCS ranged from 21 to 84 years old, with a mean age of 52.3 years and a male-to-female ratio of 1:5. At the last follow-up, all patients were alive, with 2 experiencing recurrence and metastasis. In these cases, four were classified as the classical subtype, four as the angiomatoid/sclerosing subtype, and four as the lymphoma-like subtype, with two cases also exhibiting epithelioid granulomas. All patients exhibited heterogeneous expression of follicular dendritic cell markers (CD21, CD23, CD35, and CXCL13) alongside the fibroblast marker SMA, with significantly higher expressions of IgG4, EBER, and SMA in EBV + IFDCS patients compared to FDCS patients (P < 0.05). Conversely, SSTR2, EGFR, and STAT3 expression were significantly lower in the EBV + IFDCS group (P < 0.05). The average value of EBER was significantly higher in the classical subtype group (P = 0.022). Among the four cases of EBV + IFDCS analyzed for molecular genetic features, one patient exhibited germline mutations in the CDKN1C, PDGFRA, MSH2, FANCG, MLH1, ALK, and RUNX1 genes; three exhibited simultaneous SNP variations in the MTHFR gene; and two exhibited simultaneous SNP variations in the NQO1 gene. We conducted KEGG pathway analysis on the mutant genes, revealing significant enrichment in the cAMP signaling pathway, which plays a crucial role in tumor development. Survival analysis demonstrated that the median PFS rates were not reached (NR) for EBV + IFDCS patients, compared to 5 months (HR = 7.76) for FDCS patients. The 3-year PFS rates were 66.67% and 16.67%, respectively. Compared with the FDCS group, EBV + IFDCS patients had a significantly longer median PFS time (p < 0.05). In conclusion, EBV + IFDCS represents a group of tumors with unique clinical, morphological, immunological, prognostic, and molecular cytogenetic characteristics.

12324 Clinical Features And PHEX Variants Of Adults With X-Linked Hypophosphatemia

Abstract Disclosure: L.P. Valadares: None. D.R. Carvalho: None. F.S. Lopes: None. R.S. Oliveira: None. L.G. Castro: None. X-linked hypophosphatemia (XLH), caused by loss-of-function PHEX mutations, is a lifelong renal phosphate-wasting disorder and the main cause of inherited hypophosphatemia. In adults, chronic hypophosphatemia leads to impaired bone mineralization and persistent osteomalacia. Short stature, lower limb deformities and musculoskeletal chronic pain can significantly impact the daily lives of affected individuals. This study aimed to describe the clinical and molecular profiles of 23 adults with genetically proven XLH who are being followed at a tertiary medical center in Brazil. We conducted a retrospective analysis of their medical records. The median age at diagnosis was 3.0 years (IQR 2.0-8.0) and the mean age at first visit at the adult care unit was 30.5 years (±12.7). Their mean final height was 144.2 cm (±10.5), with a mean body mass index (BMI) of 28.1 kg/m2 (±4.9). Nine patients were overweight, and seven were obese. Sixteen patients had a positive family history of rickets, and nine had offspring with XLH. Among the 14 different PHEX mutations that were identified, six had not been previously reported. Hypophosphatemia was observed in 21 patients at presentation at the adult care unit, increased serum alkaline phosphatase levels in 19, and 12 showed increased PTH levels. Chronic bone and muscular pain were reported by sixteen patients, eighteen had lower limb deformities, and six had a history of fractures and/or pseudofractures. Seventeen patients underwent orthopedic surgeries, with an average of 3.8 surgical interventions per patient. Nephrolithiasis and/or nephrocalcinosis were observed in nine patients, but none had glomerular filtration rate below 60 mL/min adjusted to 1.73 m2 of body surface. Three patients were on conventional treatment (phosphate and calcitriol) upon presentation at the adult care unit, five patients had never received XLH-specific treatment, and fifteen discontinued conventional therapy after completing skeletal growth, with a mean therapy duration of 12.1 years (±3.5). Out of the 20 patients without treatment, 16 were initiated on pharmacological therapy based on symptoms and signs of persistent osteomalacia. Eleven started combined phosphate and calcitriol supplementation, while five received calcitriol monotherapy. This cohort underscores that adults with XLH experience significant musculoskeletal morbidity throughout their lives, and require long-term follow-up, including assessment of energy metabolism. Importantly, most of them benefits from maintaining pharmacological treatment in adulthood. Presentation: 6/2/2024

6590 Androgen Derived Hepatocellular Adenoma And Reinitiation Of Gender Affirming Hormone Therapy

Abstract Disclosure: A.L. McKenna: None. Y. Huang: None. L. Yang: None. N. Loo: None. C. Ritchie: None. A. Metcalfe: None. R. Nakhleh: None. M. Krishna: None. S. Thota-Kammili: None. J. Eleazer: None. A.Y. Chang: None. Hepatocellular adenomas (HCA) are uncommon, benign epithelial tumors of the liver. Risk factors include exogenous estrogen or androgen use, and genetic and metabolic syndromes. Management of HCA is delineated by sex assigned at birth; Observation is recommended in an HCA less than 5 cm in an individual assigned female at birth, while resection of an HCA in an individual assigned male at birth is recommended no matter the size due to risk of malignant transformation. What is not known is whether risk is different for individuals with gender incongruence on gender affirming hormone therapy (GAHT). There is limited data on the risk of HCA in this population. One case report of a transgender man who continued GAHT after diagnosis of an HCA though no follow-up information was available. We present follow-up on a transgender man assigned female at birth with multiple hemorrhagic HCA that was re-initiated on GAHT after stabilization of adenomas off GAHT. Unlike prior cases, the molecular profile showed ß-catenin negative, estrogen and androgen receptors positive. This is the first case report to our knowledge reporting detailed follow-up after restarting masculinizing GAHT after diagnosis of HCA. A 24-year-old transgender man presented to the emergency department with right upper quadrant pain. Initial labs were notable for ALT of 239 units per liter (U/L) and AST 165 U/L. Magnetic resonance imaging (MRI) of the abdomen and liver elastogram revealed multiple bilobar hepatic masses, the largest measuring 9.9 cm concerning for hemorrhagic HCA which was subsequently confirmed on liver biopsy. Immunostains were positive for estrogen and androgen receptors. The patient had no history of alcohol or illicit drug use, tattoos, or family history of liver disease. The patient had been treated with 100 mg of intramuscular testosterone cypionate weekly for the past six years for gender incongruence locally. No testosterone concentrations were available from prior to or during acute presentation. Discontinuation of hormone therapy was recommended along with conservative management with frequent MRI. Over the next 19 months, monitoring revealed improvement/resolution of the auto infarcting adenomas with the last MRI noting two stable HCA measuring 2.1 cm and 0.8 cm without new or enlarging liver lesions. Due to gender dysphoria off GAHT, reinitiation of hormone therapy with low dose AndroGel 1.62% topically was prescribed at 18 months after presentation. The patient has been monitored with labs monthly and plans to obtain MRI abdomen every three months. To date, the patient has tolerated reinitiation of therapy. This case demonstrates that patients on masculinizing GAHT who develop HCA can be conservatively managed and monitored based on pathology and that testosterone does not necessarily explain sex differences in the presentation/malignant transformation of HCA cisgender men as opposed to cisgender women. Presentation: 6/3/2024

Proton beam therapy in a patient with secondary glioblastoma (32 years after postoperative irradiation of medulloblastoma): case report and literature review

ObjectiveThis report details the experience of a patient who developed a second primary glioblastoma (GB), offering insights into the treatment process and reviewing relevant literature.Case presentationA male patient, who was diagnosed with medulloblastoma at age 9, received treatment with cobalt-60 craniospinal irradiation (CSI) (36 Gy/20 fractions) and a tumor bed boost (total of 56 Gy). After 32 years, at age 41, an MRI revealed a space-occupying mass in the left cerebellar hemisphere. Surgical resection was performed, and postoperative pathology confirmed a diagnosis of radiation-induced glioblastoma (RIGB). Given the history of irradiation and the current tolerability of brainstem doses, proton beam therapy (PBT) combined with Temozolomide (75 mg/m2) was chosen. The treatment plan included 60 Gy on the gross tumor bed and 54 Gy on the clinical target volume, delivered in 30 fractions. The patient underwent regular follow-up and achieved a complete response.Clinical discussionFor childhood cancer survivors, the development of a second primary tumor significantly impacts prognosis. RIGB is a rare form of secondary tumor with distinct molecular characteristics compared to primary GB and recurrent secondary GB. Molecular markers such as IDH and MGMT status can help differentiate between primary GB, recurrent secondary GB, and radiation-induced secondary GB in patients with a history of prior radiation therapy. Surgical resection remains a primary treatment option, while PBT is preferred for postoperative treatment due to its superior protection of normal tissues and the ability to deliver high-dose irradiation.ConclusionRIGB is a rare second primary tumor that requires strategic molecular profiling and individualized management. Proton beam therapy provides effective high-dose irradiation in the postoperative phase and is the preferred treatment option for such cases.

7826 The Identification of an Activating ESR1 Mutation in an Aggressive Prolactinoma Enabled the Use of Personalized Treatment

Abstract Disclosure: T. Paes: None. J.B. Mebarak: None. J. C. Magnotto: None. G. A. Stamatiades: None. Y. Kuang: None. C. Paweletz: None. E.R. Laws: None. R.S. Carroll: None. R. Jeselsohn: None. D. R. Mohan: None. A. Marcondes Lerario: None. W. L. Bi: None. D. A. Reardon: None. D. M. Meredith: None. U.B. Kaiser: None. A. Abreu: None. Introduction: Prolactinomas are benign tumors typically treated with dopamine agonists; few progress on medical therapy, through unclear molecular mechanisms. Although the SF3B1 mutation has been identified in one study as a driver of aggressive prolactinomas, in most cases no genetic mutations have been reported. We aimed to identify genetic alterations associated with prolactinomas using a gene panel. Method and Results: Oncopanel, a massively parallel sequencing panel, was performed to identify genomic variants and copy number variation (CNV) in a cohort of 21 patients with prolactinomas. No SF3B1 pathogenic variants were identified in this cohort. A MEN1 mutation was detected in a macroadenoma resistant to dopamine agonist. In a case of an extremely aggressive prolactinoma diagnosed in a 49-year-old woman, a somatic ESR1 [encoding estrogen receptor alpha (ERα)] mutation (ESR1Y537S) was identified in tissue from the patient’s fourth surgery. Using droplet digital PCR (ddPCR), ESR1Y537S was also detected in circulating cell-free DNA. We aimed to investigate whether ESR1Y537S may have driven initial tumor formation, or whether it was acquired as the tumor progressed. To this end, Sanger sequencing and ddPCR analyses of DNA from the first two resected tumors were performed and failed to identify ESR1Y537S. In the CNV analysis, the ESR1-mutated prolactinoma had the highest number of CNVs, compared to the rest of the cohort. Despite efforts to control tumor growth with multiple therapeutic modalities, the mutated prolactinoma had progressively enlarged post-menopausally, with invasion of surrounding structures. ESR1Y537S is a hotspot mutation in metastatic breast cancer. In breast cancer cells, ESR1Y537S activates the ERα independent of ligand binding, resulting in high cell proliferation and conferring resistance to classic hormonal treatment in ER-positive breast cancer. Elacestrant, a second-line ER degrader, increases overall free-survival in patients with resistant breast cancer and ESR1Y537S. Given the lack of response to multimodality therapy, off-label elacestrant was initiated after the third cycle of radiotherapy was completed in the patient with the aggressive prolactinoma. The combination of radiotherapy with this personalized treatment targeting ESR1 activity (elacestrant) was able to control tumor growth and significantly reduce prolactin levels. Conclusion:ESR1 regulates lactotroph differentiation and proliferation, possibly contributing to prolactinoma tumorigenesis. Our data support a role for ESR1Y537S in this prolactinoma’s unusually aggressive behavior in the postmenopausal setting. Molecular profiling revealing the mutation (ESR1Y537S) allowed the patient to receive a targeted therapy which, together with radiotherapy, resulted in a decrease in prolactin levels and a remarkable improvement in disease control. Presentation: 6/2/2024

6711 Single Nuclei RNA-seq To Map Adipose Cellular Populations And Senescent Cells In Response To A Lifestyle Or Senolytic Intervention In Older Adults With Obesity: A Double-Blind, Placebo-Controlled, Randomized Trial

Abstract Disclosure: A. Aslamy: None. G. Connolly: None. J. Nie: None. S. Espinoza: None. M. Serra: None. N. Musi: None. It is well established that obese and older individuals are at significantly increased risk for diabetes and metabolic syndrome. However, the underlying molecular mechanisms by which increased adiposity and aging predisposes individuals to metabolic disease are not well understood. Recent data suggests that variations in adipocyte cellular populations and subpopulations influence whole body metabolism. Particularly, an increased burden of adipocyte senescent cells (cells that are in a state of replicative arrest) have been implicated in metabolic diseases. To investigate the relationship between adipose molecular signatures and cellular senescence on metabolic outcomes, we will use a novel, high-throughput, high-resolution methodology called single nuclei RNA sequencing (SnRNA-seq) to develop a transcriptomic atlas of human adipose tissue and analyze molecular profiles before and after interventions of lifestyle vs. senolytic vs. placebo. We will recruit a cohort of older obese participants (≥65 years of age; BMI = 30-39.9 kg/m2; n = 72), and conduct a double-blinded, placebo-controlled, randomized trial in which we obtain adipose biopsies to analyze cellular/molecular profiling via snRNA-seq as it relates to phenotypic measures of insulin sensitivity, glucose tolerance, beta cell function, and hepatic lipid content compared to cohorts of younger lean (18-30 years of age; BMI = 18.5-24.9 kg/m2; n = 24) and older lean (≥65 years of age; BMI = 18.5-24.9 kg/m2; n = 24) participants. Older obese participants will be randomized to one of three groups for a 10-week period: lifestyle (diet- and exercise-induced weight loss of 8-10% of body mass), senolytic (dasatinib and quercetin), or placebo. Repeat adipose biopsies and metabolic testing will be analyzed before and after intervention to assess potential changes in gene expression and associated phenotypic measures. Inclusion criteria for the older obese participants are the following: ≥65 years of age, BMI 30-39.9 kg/m2, any sex, race and ethnic group, sedentary (≤1.5h of exercise per week), and nondiabetic. Exclusion criteria include history of diabetes, participation in structured exercise &amp;gt;1.5h per week, chronic inflammatory/neurologic/autoimmune/pulmonary disorders, GI or heart disease, use of anti-arrhythmic or weight altering medications, smoking/alcohol use, previous bariatric surgery, and use of/allergy to senolytic agents. Preliminary snRNA-seq analyses of adipose biopsies from our pilot study with non-diabetic participants identified cells with elevated expression of positive regulators of senescence (CDKN1A, CDKN2A, ARG2); notably, one subpopulation of senescent adipocytes, termed NewA1, was increased with higher BMI. Overall, the findings from this study may help us gain better understanding of the aging process and identify potential molecular targets for prevention of metabolic disease. Presentation: 6/1/2024

Clinical and Molecular Profiles of a Cohort of Egyptian Patients with Collagen VI-Related Dystrophy

Collagen VI-related dystrophies (COL6-RD) display a wide spectrum of disease severity and genetic variability ranging from mild Bethlem myopathy (BM) to severe Ullrich congenital muscular dystrophy (UCMD) and the intermediate severities in between with dual modes of inheritance, dominant and recessive. In the current study, next-generation sequencing demonstrated potential variants in the genes coding for the three alpha chains of collagen VI (COL6A1, COL6A2, or COL6A3) in a cohort of Egyptian patients with progressive muscle weakness (n = 23). Based on the age of disease onset and the patient clinical course, subjects were diagnosed as follows: 12 with UCMD, 8 with BM, and 3 with intermediate disease form. Fourteen pathogenic variants, including 5 novel alterations, were reported in the enrolled subjects. They included 3 missense, 3 frameshift, and 6 splicing variants in 4, 3, and 6 families, respectively. In addition, a nonsense variant in a single family and an inframe variant in 3 different families were also detected. Recessive and dominant modes of inheritance were recorded in 9 and 8 families, respectively. According to ACMG guidelines, variants were classified as pathogenic (n = 7), likely pathogenic (n = 4), or VUS (n = 3) with significant pathogenic potential. To our knowledge, the study provided the first report of the clinical and genetic findings of a cohort of Egyptian patients with collagen VI deficiency. Inter- and intra-familial clinical variability was evident among the study cohort.

8788 Implications of NTRK gene fusion in Papillary thyroid cancer

Abstract Disclosure: W. Medina-Torres: None. L. El Musa Penna: None. J. Segarra-Villafane: None. L.R. Sepulveda-Garcia: None. Z. Maisonet -Feliciano: None. I.C. Arroyo: None. M. Ramirez: None. M. Alvarado: None. L.A. Gonzalez-Rodriguez: None. V.J. Carlo: None. Thyroid cancer (TC) is the most common endocrine cancer. Papillary thyroid carcinoma (PTC) is the predominant contributor of this occurrence, comprising approximately 80% of all thyroid carcinomas. PTC has a good prognosis with a 5-year survival rate of more than 90% after resection. Nonetheless, factors such as tumor size, multifocality, nodal and distant metastases, characterize more aggressive cases including tall cell variant, columnar cell variant, and hobnail variant Aside from staging parameters, PTC behavior is mostly determined by morphologic variant. This is the case of 31 y/o female without known past medical history who was evaluated at endocrinology clinic due to a fine needle thyroid aspiration (FNA) positive for PTC, tall cell variant. Total thyroidectomy with central compartment dissection was performed. Pathology report presented a main tumoral mass of 3 cm but permeating multinodular pattern involving the entire gland with focal extrathyroidal extension, positive margins and six level VI positive lymph nodes. As per report, the tumor presented both papillary and follicular patterns of growth and other findings including oncocytic change, foci of clear cell change, low mitotic rate, and most notably "reverse polarization”. This pattern has the pathological features suggestive of the novel NTRK gene fusion mutation. The patient was treated with radioactive iodine (RAI) and one year post treatment there was evidence of elevated Thyroglobulin level at 904 ng/mLand thyroglobulin Ab at 2.48 IU/mL. A WBS +SPECT was done resulting in small uptake at left posterior thyroid bed and pulmonary intake. A chest CT revealed multiple bilateral sub centimeter nodules. Based on this result, a second course of RAI was given. Follow up neck ultrasound and chest CT presented persistent left level VI lymph nodes, increased amount of bilateral sub-centimeter pulmonary nodules and new thoracic(T11) lesion. FNA of left neck lymph nodes were positive for metastatic PTC for which left neck dissection was performed. Evaluation for actionable somatic mutations was requested based on resistance behavior, remarkable for TRIM33-NTRK1 chromosomal rearrangement. Patient was evaluated by Oncology service who started Larotrectinib treatment since it was approved for NTRK driven malignancies. Six-month post therapy patient achieved clinical and biochemical improvement. In the thyroid, NTRK-driven malignancies are rare and aggressive but treatable, in the evolving genomic era. As reviewed in the literature, NTRK fusion-positive TC exhibits distinctive clinicopathological features that could aid in identifying potential patients. Thus, in such patients who have PTC with non-classic pathologic patterns, specific molecular profile of the main tumor may have significant prognostic value that must be integrated into stratification system in order to provide target therapy on time. Presentation: 6/3/2024

Sex differences in the molecular profile of adult diffuse glioma are shaped by IDH status and tumor microenvironment.

Sex differences in adult diffuse glioma (ADG) are well-established clinically, yet the underlying molecular mechanisms remain inadequately understood. Here, we aim to reveal molecular features and cellular compositions unique to each sex in ADG to comprehend the role of sex in disease etiology. We quantified sex differences in transcriptome of ADG using multiple independent glioma patient datasets. Next, we delved into the single-cell landscape to examine sex differences in gene expression and cellular composition. To explore how sex influences disease progression, we analyzed paired samples from primary and recurrent ADG cases, aiming to identify sex-specific differences in molecular and cellular features. Our analysis revealed that mutations in isocitrate dehydrogenase (IDH) genes and the tumor microenvironment emerged as primary influencers of sex-differential molecular enrichments. In IDHwt tumors, genes in neuronal signaling pathway are found to be enriched in male tumors, while genes in hypoxia and inflammatory response pathways are enriched in female tumors. This pattern was reversed in IDHmut gliomas. We hypothesized that these distinctions could be attributed to heterogeneous cellular composition between sexes. Using single-cell data, we observed distinctive patterns of sex differences in cell states, cell composition and cell-cell interaction in IDHwt and IDHmut tumors separately. Further, by comparing molecular changes in paired primary and recurrent ADG samples, we identified sex-specific differences in molecular characteristics and cellular compositions of recurrent tumors. Our results provide a comprehensive multi-level characterization of sex differences in ADG, such findings provide novel insights into glioma disease progression in each sex.

6641 Observation in Lieu of Surgical Management in Hurthle Cell Neoplasm: Role of Thyroseq V3 Molecular Testing

Abstract Disclosure: R. Kaur: None. L. Kaur: None. T. Chaudhary: None. M. Shrivastava: None. N. Patel: None. The diagnostic utility of fine needle aspiration biopsy with cytology is often confounded in thyroid nodules with predominance of hurthle cells, often interpreted as an oncocytic/hurthle cell lesion with intermediate risk of malignancy, bethesda category (BC) III or IV. With the advent of molecular testing like thyroseq V3, it is helpful in ruling out substantial risk of cancer and considering observation in lieu of surgical management in such difficult cases. We present a case of a 75 year old woman with past medical history significant for type 2 diabetes mellitus and hypothyroidism who was found to have a left lobe complex nodule within a non-toxic multinodular goiter In 2022. Ultrasound of the neck showed a 1.6 x 1.8 x 2 cm intermediate nodule, followed by a fine needle aspiration biopsy which was non-diagnostic and reported as benign, showing only cystic contents and insignificant follicular cells, Bethesda class II. Follow up for the nodule was recommended in one year. Repeat Imaging one year later revealed left nodule without significant changes and repeat fine needle aspiration cytology was advised. The biopsy result was reported as an oncocytic/ Hurthle cell neoplasm, Bethesda class IV. The specimen was also submitted for thyroseq molecular testing and results were awaited. The patient was euthyroid with negative anti thyroid antibodies. There was no family history of thyroid cancer or radiation exposure. The patient denied any active symptoms like shortness of breath, neck pain or pressure, recent voice changes, dysphasia, loss of appetite or weight .On examination the patient was found to have a left thyroid nodule with no signs of tracheal deviation. CT scan of the neck demonstrated a left thyroid nodule with no compression. The patient was followed by both endocrinology and oncology and surgical options were discussed depending upon the biopsy results while awaiting molecular testing report. Molecular testing with thyrosec V3 revealed an absence of gene mutations and reported a low probability of cancer. Depending upon the results observation was considered in lieu of surgical management. Hence It was decided to keep the patient under observation considering the molecular test results in conjunction with all relevant imaging, clinical findings, symptoms, patients family history as well as patients preference. This case report demonstrates the crucial role of molecular Diagnostics specifically thyroseq V3 in the often difficult clinical management of hurthle cell thyroid nodules for ruling out surgical management. Thyroseq V3 shows reliable performance in Hurthle cell cancers with sensitivity of 93% and specificity of 69%. In times of patient guided decision making and ability to narrow down the need of surgery based on pre-operative fine needle aspiration cytology, molecular profiling of thyroid nodules has become increasingly utilized. Presentation: 6/1/2024

12205 Challenging Case Of Anaplastic Thyroid Cancer With Unusual Histological Features: A Diagnostic Dilemma With High Grade Sarcoma

Abstract Disclosure: B. Gautam: None. B. Tiwari: None. M.S. Hossain: None. S. Hossain: None. S.C. Kumar: None. H. liao: None. Introduction: Anaplastic thyroid carcinoma (ATC) is a rare but highly aggressive thyroid cancer accounting for &amp;lt; 2% of cases, characterized by its rapid growth, extensive local invasion, and poor prognosis. Distinguishing ATC from other high-grade sarcomas, such as leiomyosarcoma, is challenging due to shared morphological features and overlapping immunoprofiles. We present a case involving a 73-year-old male presenting with rapidly growing neck mass, leading to diagnostic challenges differentiating between ATC and high-grade sarcomas. Case presentation: A 73-year-old male presented to ED with a rapidly growing painful neck mass for last 3 months, associated with dysphagia, dyspnea &amp; dysphonia. He denied any fever, chills, weight loss and symptoms of hyperthyroidism or hypothyroidism. No personal or family history of thyroid cancer. On physical exam: vitals were normal, Neck exam revealed a left sided neck mass, mobile with deglutition, hard in consistency associated with hoarseness of voice. No stridor or wheeze noted on auscultation. Physical exam was otherwise normal. Laboratory tests showed normal CBC, CMP and TSH 1.45 mIU/L, T4 9.7 ug/dl. CT neck with contrast showed 5.4 x 5.6 x 8.2 cm large lobulated left thyroid mass with rightward airway deviation &amp; substernal extension. Ultrasonogram of thyroid showed 9.6 x 5.3 x 3.3 cm left thyroid lobe with internal calcifications &amp; extrathyroidal extension with several abnormal appearing cervical lymph node, largest measuring 4.9 x 2.4 x 3.3 cm. CT chest/abdomen/pelvis with contrast showed multiple bilateral lung nodules measuring up to 1.5 cm and 1.4 x 1.3 cm left gluteal soft tissue mass. IR-guided left neck mass biopsy was suggestive of primary spindle cell neoplasm with initial immunoprofiles consistent with a high-grade sarcoma, favoring leiomyosarcoma. Given the rapid growth of the neck mass with associated dyspnea, left thyroidectomy was performed and surgical pathology was suggestive of a high-grade sarcoma. However, subsequent pathology review made a final diagnosis of ATC, based on morphologic &amp; immunohistochemical profile showing tumor cells strongly positive for p53 and Desmin with few cells positive for PAX-8, Cam 5.2 and CD68, and negative thyroglobulin, TTF-1, CK7, CK20, CK MNF116, pancytokeratin AE1/AE3 and CK5/6. Thyroseq revealed a distinctive molecular profile specifically positive for TERT and TP53 supporting diagnosis of ATC. Discussion: This case highlights the diagnostic dilemma posed by the resemblance between ATC and high-grade sarcomas due to overlapping clinical, morphological and immunohistology features. While both malignancies may exhibit similar morphological features, specific immunohistochemistry profiles along with molecular testing aid in distinguishing between them and guiding appropriate treatment strategies. Presentation: 6/1/2024