Heterogeneous Group Research Articles

Pharmacokinetic Variability of Rufinamide and Stiripentol in Children With Refractory Epilepsy: A Retrospective Study of Therapeutic Drug Monitoring From the National Epilepsy Centers in Denmark and Norway.

Rufinamide and stiripentol, orphan drugs used in Lennox-Gastaut and Dravet syndromes, respectively, are antiseizure medications (ASMs), often administered to children; however, pharmacokinetic studies are lacking. The authors compared the pharmacokinetic variability of these drugs with respect to the dose, serum concentrations, comedication, age, and duration of treatment. Children and adolescents (<18 years) whose serum concentrations were measured were retrospectively identified from the therapeutic drug monitoring (TDM) databases at 2 national epilepsy centers in Norway and Denmark (2012-2021). Data from 165 patients (56% boys/44% girls) treated with rufinamide and 52 patients (50% boys/50% girls) treated with stiripentol were included. For rufinamide, the median age was 10 (range 2-17) years, dose 23 (3-73) mg/d, and serum concentration 34 (3-227) µmol/L [8.1 mg/L (0.71-54.0 mg/L)]. For stiripentol, the median age was 8.5 (range 1-17) years, dose 37 (18-76) mg/d, and serum concentration 33 (4-113) µmol/L [7.7 mg/L (0.93-26.3 mg/L)]. The concomitant use of 1-9 other ASMs during the data collection was noted. Pharmacokinetic variability, calculated as the concentration/(dose/kg) ratio, ranged from 0.26 to 11.31 (µmol/L)/(mg/kg) for rufinamide and 0.17-1.52 (µmol/L)/(mg/kg) for stiripentol. The intraindividual coefficients of variation ranged widely, from 5% to 110% for rufinamide and 11%-117% for stiripentol. The treatment period was at least 5 years in 50% of patients. No statistically significant effects of age, sex, or ASM comedication were observed, possibly due to the small sample size and heterogeneous groups with variable seizure situations, comorbidities, and changes in comedication and physiology. This study demonstrates considerable pharmacokinetic variability in and between patients for both drugs and similar use in terms of age, burden of comedication and retention rates. TDM may be useful in the clinical setting to monitor and optimize treatment in this vulnerable patient group.

Sinonasal Tumors: What the Multidisciplinary Cancer Care Board Wants to Know.

Sinonasal neoplasms are a remarkably heterogeneous group, reflecting the numerous tissue types present in the nasal cavity and paranasal sinuses. These entities can be relatively benign (ie, respiratory epithelial adenomatoid hamartoma) or can be exceedingly aggressive (ie, NUT carcinoma). Certain sinonasal tumors have a propensity to spread through local invasion and destruction, while others have a high likelihood of perineural spread. The genetic and molecular mechanisms underlying sinonasal tumor behavior have recently become better understood, and new tumor types have been described using these genetic and molecular data. This has prompted an expansion in the number of tumors included in the World Health Organization fifth edition classification system for head and neck tumors, along with a new classification structure. Radiologists' familiarity with this classification structure is crucial to understanding the expected behavior of these tumors and to collaboration with the multidisciplinary cancer care board in making decisions for optimal patient care. ©RSNA, 2024.

Levels of Natural Antibodies Before and After Immunoglobulin Replacement Treatment Affect the Clinical Phenotype in Common Variable Immunodeficiency

Natural antibodies (NAbs) occurring in individuals without prior exposure to specific antigens, provide direct first barrier protection against pathogens, and exert immunoregulation thus actively contributing to the maintenance of immune homeostasis, controlling inflammatory processes and preventing autoimmunity. Common variable immunodeficiency (CVID) is a heterogeneous group of disorders characterized by a compromised immune function that brings into focus the role of NAbs. Our aim was to explore whether NAb levels could serve as potential key indicators in CVID for monitoring disease progression and predicting outcomes. In this study, we analyzed a Hellenic cohort of 56 patients with CVID (31 newly diagnosed and 25 under immunoglobulin replacement therapy-IgRT) and 33 healthy controls, for total Ig levels and serum IgM and IgG NAb levels against five informative target-antigens of NAbs, namely, actin, DNA, carbonic anhydrase, F(ab΄)2 fragments of human IgG and TriNitroPhenyl. In addition, follow-up pre- and post- IgRT samples were analyzed in ten (10) patients of our cohort. Results showed that Ig-treated patients exhibited significantly lower IgM NAb levels than untreated patients and healthy controls against all panel antigens. In the follow-up samples, pre-treatment IgM NAb levels negatively correlated with total serum IgM. This imbalance was only partially restored after IgRT, with a significant decrease in IgM NAb levels observed in nine out of ten patients. Moreover, post-treatment patients with recurrent infections presented significantly lower IgM NAb levels, a reduction also observed in patients with bronchiectasis independently of treatment status. On the contrary, post-treatment patients with enteropathy had significantly higher IgM NAb levels against all panel antigens, an increase also noted in patients with autoimmune diseases. Regarding IgG NAbs, replacement therapy restored levels to those of healthy controls. In conclusion, impaired NAb levels are found in CVID patients, particularly related to certain phenotypes. Moreover, the significant decrease in IgM NAb levels after IgRT suggests a potential association with disease course and complications. The results suggest that administration of human IgM NAbs may be an effective combinatorial treatment in selected patients. Further research is needed to understand the functional roles of NAbs in CVID and its complex clinical phenotypes.

Epidemiology and socioeconomic correlates of brain and central nervous system cancers in Asia in 2020 and their projection to 2040

Brain and central nervous system (CNS) cancers constitute a heterogeneous group of cancers with poor 5-year survival rates. We aimed to report the epidemiology of brain and CNS cancers in Asia in 2020 and their projections up to 2040 by age, sex, and country, as well as their correlation with socioeconomic status. We extracted data from the 2020 Global Cancer Observatory (GLOBOCAN). Numbers, age-standardized incidence rates (ASIRs) and mortality rates (ASMRs), 5-year prevalent cases and rates, mortality-to-incidence ratios (MIRs), and crude rates were calculated. The human development index (HDI) and current healthcare expenditure (CHE)-to-gross domestic product (GDP) ratio were included as indicators of socioeconomic status. Additionally, the numbers of new cases and deaths were predicted from 2025 to 2040 by multiplying the anticipated population during this period by age-standardized rates. In 2020, there were 166,925 new cases of brain and CNS cancers in Asia, indicating a 5-year prevalence rate of 9.40 per 100,000. We also estimated the total ASIR, ASMR, and MIR as 3.20, 2.60, and 0.83, respectively. There were significant negative correlations between HDI and MIR (correlation coefficient: − 0.538, p value < 0.001) and significant positive correlations between CHE/GDP% and ASIR (correlation coefficient: 0.388, p value: 0.010) and ASMR (correlation coefficient: 0.373, p value: 0.014). In 2040, there will be 232,000 new cases of brain and CNS cancers and 200,000 subsequent deaths in Asia. Our study revealed higher brain and CNS cancer rates in Western Asia among males and elderly individuals. These findings can aid policymakers in enhancing cancer care and suggest the consideration of risk factors in future research.

Co-producing and co-assessing a new service solution for enhancing health and social care integration: a participatory research protocol

BackgroundThis paper describes a study protocol for co-producing and co-assessing a new sustainable and scalable service solution that enhances health and social integration by involving providers and volunteers delivering services for elderly people in the province of Cremona (Italy), where the elderly population will reach 27% in 2023.MethodsThis upcoming study involves mixed-method participatory research and is structured in three study phases and related objectives. First, it will co-produce a new, accessible and sustainable service solution using an iterative design and management method, Plan-Do-Check-Act by involving professionals and volunteers of a heterogeneous group of health, social and third sector organizations located in the city of Cremona (Italy). Second, the study protocol will co-assess the outcomes of the new service solution using a mixed-method approach for measuring the outcomes on: professionals and volunteers (micro level) and their health, social and third sector organizations (meso level). Third, this study will co-investigate the scalability of the new solution promoting health and social integration in other similar urban areas of the Province of Cremona via the Intervention Scalability Assessment Tool (macro level). The data will be collected through the analysis of official documents, websites, policies and participatory workshops.DiscussionThis protocol proposes an innovative intervention, a novel participatory approach, and an unexplored scalability assessment tool in the context of health and social care integration. This study aims to support professionals from health and social care service providers and volunteers from third-sector organizations to collaborate and integrate each other’s resources. In doing so, the participatory approach will facilitate the co-creation of an effective response to the need of health and social integration, and the development of trustful relationships between health and social care service providers. Moreover, the adoption of Plan-Do-Check-Act and Intervention Scalability Assessment Tool will ensure the quality, scalability and sustainability of the new service solution in other settings.

Analysis of clinicopathological characteristics and prognostic factors in 54 metaplastic breast carcinoma patients from northwest China

Objective: Metaplastic breast carcinoma (MBC) is a special type of morphologically heterogeneous and aggressively invasive breast cancer. MBC is characterized by the transformation of tumor epithelium into squamous epithelium and/or mesenchymal components, including differentiation into spindle cells, chondrocytes, and osteocytes. Due to its rarity and invasiveness, there is a paucity of research on MBC prognosis. Furthermore, there are currently no treatment guidelines for MBC. This study analyzed the clinicopathological characteristics, immunophenotype, and prognostic features of MBC. Our aim was to better characterize MBC, thereby identifying potential prognostic factors and new treatment methods. Moreover, we also describe an MBC case treated experimentally with anti-vascular targeted therapy. Material and Methods: We retrospectively analyzed clinical pathological data on 54 female patients with MBC from Shaanxi Provincial People’s Hospital and the XiJing Hospital of Air Force Medical University. These cases were diagnosed with MBC between January 1st, 2013, and October 1st, 2018. All patients were from the northwest region of China. The gross morphological, histological, and immunohistochemical features of MBC were analyzed. Kaplan–Meier analysis was used to calculate the survival rate, and univariate analysis was performed to identify significant prognostic factors. In addition, the treatment of an MBC patient with anti-angiogenic therapy was described, and a relevant literature review was conducted. Results: MBC was diagnosed in 32 left breasts and 22 right breasts from 54 women aged 21–76 years (median age of 57 years). The maximum tumor diameter ranged from 0.6 to 14 cm (average of 4.1 cm). Of the 54 patients, 47 underwent surgical treatment, with lymph node metastasis found in 17.0% (8/47). According to the World Health Organization classification criteria for breast tumors, the study cohort consisted of 15 cases of squamous cell carcinoma, ten cases of spindle cell carcinoma, nine cases of carcinoma with associated stromal differentiation, 18 cases of mixed carcinoma, and two cases of adenocarcinoma with squamous differentiation. Based on the American Joint Committee on Cancer clinical staging criteria, the patients were classified as Stage I (10 cases, 18.5%), Stage II (26 cases, 48.1%), Stage III (11 cases, 20.4%), and Stage IV (7 cases, 13.0%). Immunohistochemical analysis revealed that 94.4% of patients had triple-negative breast cancer (TNBC), 47 cases showed mutant tumor protein 53 (TP53) expression, 29 cases showed positive epidermal growth factor receptor (EGFR) expression, 43 cases showed positive E-cadherin expression, and 37 cases showed positive Cluster of Differentiation 24 expression. The Ki-67 index ranged from 20% to 90%. Univariate analysis showed that the Ki-67 index was not significantly associated with either progression-free survival (PFS) or overall survival (OS) in MBC patients. Patients with negative axillary lymph nodes had significantly better PFS and OS than those with positive nodes (P &lt; 0.05), and patients with clinical stage I-II disease had better PFS and OS than those with stage III-IV disease (P &lt; 0.05). Patients treated with anthracycline-containing chemotherapy had significantly better PFS than those who did not receive chemotherapy. Univariate analysis revealed that the high expression of EGFR correlated with worse PFS (P &lt; 0.05). The type of surgical approach employed did not affect the prognosis of MBC patients. Following the application of anti-angiogenic therapy, a rapid partial response was observed in an MBC patient with carcinoma and associated stromal differentiation. This patient subsequently underwent surgery and radiation therapy and has now achieved over 6 years of PFS. Conclusion: MBC is a heterogeneous group of tumors with high malignancy and poor prognosis. The large majority is TNBC and exhibits unique immune phenotypes. The poor PFS of MBC patients may be related to EGFR expression, which could become a potential therapeutic target in these patients. Surgery remains the primary treatment method for MBC. The present study found that sentinel lymph node biopsy was feasible in appropriate patients, and that chemotherapy regimens incorporating anthracycline-class drugs did not appear to improve OS. Anti-angiogenic therapy holds promise as a potentially effective treatment approach for MBC, and the optimization of systemic treatment strategies should be a priority in the management of these patients.

Drug-induced lung disease: a narrative review

Drug-induced lung disease (DILD) encompasses a broad, highly heterogeneous group of conditions that may occur as a result of exposure to numerous agents, such as antineoplastic drugs, conventional or biological disease-modifying antirheumatic drugs, antiarrhythmics, and antibiotics. Between 3% and 5% of prevalent cases of interstitial lung diseases are reported as DILDs. The pathogenesis of lung injury in DILD is variable, multifactorial, and often unknown. Acute presentation is the most common, can occur from days to months after the start of treatment, and ranges from asymptomatic to acute respiratory failure. The CT patterns are varied and include ground-glass opacities, organizing pneumonia, and diffuse alveolar damage. Notably, there are no clinical manifestations or CT patterns specific to DILD, which makes the diagnosis quite challenging and necessitates a high index of suspicion, as well as the exclusion of alternative causes such as infection, cardiac-related pulmonary edema, exacerbation of a preexisting ILD, and neoplastic lung involvement. Discontinuation of the offending medication constitutes the cornerstone of treatment, and corticosteroid treatment is usually necessary after the onset of clinical manifestations. The prognosis varies widely, with high mortality rates in severe cases. A history of medications related to pulmonary toxicity in patients with new-onset respiratory symptoms should prompt consideration of DILD as a potential underlying cause.

Can we differentiate patients with dysferlinopathies and inflammatory myopathies by ultrasound? A discriminant analysis study.

Idiopathic inflammatory myopathies (IIM) are a heterogeneous group of diseases that are characterized by inflammation and muscle weakness. Dysferlinopathies are autosomal recessive limb-girdle muscular dystrophies caused by mutations in DYSF, which share a similar clinical presentation and histopathological inflammatory changes. To determine the sonographic differences between dysferlinopathies and IIM and whether these differences allow their classification. This observational, cross-sectional, and analytical study evaluated 20 muscles from 11 patients with dysferlinopathies and 11 patients with IIM. The patients were matched for age, sex, and disease duration. Clinical and laboratory variables were analyzed. Semi-quantitative scales were used to weigh the gray scale and power Doppler muscle abnormalities. Descriptive statistics were computed and discriminant analysis was performed to determine the ultrasound variables that best predicted the final diagnosis. Forty muscles were evaluated. Atrophy and higher Heckmatt scale scores were observed in patients with dysferlinopathies. A set of three muscles (biceps/brachialis, quadriceps, and gastrocnemius) had a diagnostic accuracy of 100% (sensitivity, 100%; specificity, 100%; canonical coefficient, 0.733 p < 0.001). A set of two formulas was used to classify both diseases correctly. In the present study, scanning of three muscle groups showed high diagnostic accuracy in differentiating dysferlinopathies from MII. Ultrasound can be used as an initial test in patients with suspected muscle disease or as an additional tool to support diagnosis in controversial cases.

Myelodysplastic syndrome/ Myeloproliferative disorder, Nos.

Background: Population-based research is limited for myelodysplastic syndrome/ myeloproliferative neoplasm, not otherwise specified (MDS/MPN-NOS) which comprises a heterogenous group of patients that do not fit into the other established MDS/MPN subgroups. Methods: We identified patients from the Surveillance, Epidemiology, and End Results (SEER) database with a diagnosis of MDS/MPN-U logged from 2010-2020. Age-standardized incidence rates (ASIR) and incidence rate ratios (IRR) were calculated using eight age subgroups. Subgroup analyses were performed for race and gender. Join point regression analyses were performed to model trends in ASIRs, and annual percent change (APC) was calculated. Results: A total of 2447 patients over age 50 were included in analysis. Incidence of MDS/MPN-U increased gradually between 2010-2016 (APC 12.90) then decreased between 2016-2020 (APC -19.56). ASIR was significantly higher in males compared to females in several age groups (age 65-69, 80-84, 85+). Conclusion: The underlying molecular complexity of these diseases remains a significant challenge. It is critical to identify MDS/MPN- specific therapeutic response criteria and suitable end points correlated with survival and AML risk for transformation to acute myeloid leukemia (AML) uniform assessment of treatment benefit.

A Single-Center Retrospective Cohort Study of Genotype–Phenotype Correlation of Osteogenesis Imperfecta in UAE

Abstract Background Osteogenesis imperfecta (OI) is a clinically and genetically heterogeneous group of inherited connective tissue disorders characterized by skeletal fragility. Patients with OI suffer recurrent fractures, limb deformities, and kyphoscoliosis. Multiple extraskeletal manifestations might also be present. Autosomal dominant variants in the COL1A1 or COL1A2 genes account for approximately 90% of cases. Objective The aim of the study was to describe the variant spectrum and genotype–phenotype correlations in patients with OI seen in Tawam Hospital in the UAE. Methods The authors conducted a retrospective chart review for all patients with OI assessed by geneticists at Tawam Hospital from January 2010 to December 2021. They retrieved each patient's baseline characteristics, detailed history and physical examination, laboratory, imaging, and genetic results. Results A total of 40 patients with OI were found and included in this study. The majority (80%) were Emirati, and 57.5% were females. Consanguinity was documented in 24.3%. Thirty-seven patients (92.5%) had positive molecular testing; 28 patients (75.7%) had an autosomal dominant inheritance, and 9 patients (24.3%) had an autosomal recessive inheritance. The majority had missense variants. Four variants were novel. A high prevalence of pathogenic variants in the COL1A1 gene (57%) was found. Patients with variants in the LEPRE1 gene had early and severe phenotypes, while patients with variants in the TMEM38B gene had variable presentations. The majority of patients (85%) had skeletal phenotypes: fractures, bone deformity, scoliosis, and osteopenia. Extraskeletal phenotypes included blue sclera, dentinogenesis imperfecta, hearing loss, and dysmorphic features. Conclusion This study reports the genotype–phenotype correlation of OI patients from the UAE. A high prevalence of pathogenic variants in the COL1A1 gene with OI type IV phenotype was found. Further multicenter more extensive studies are recommended.

Antenatal unilateral upper limb acromesomelic dysplasia.

Acromesomelic dysplasia (AMD) is an umbrella term given to a heterogeneous group of progressive skeletal disorders characterized by short limbed dwarfism associated with disproportionate shortening of middle and distal segments of the upper as well as lower limbs. Although specific skeletal anomalies are difficult to diagnose antenatally, but because of their antenatal and postnatal implications and a possibility of reoccurrence in following pregnancies, such skeletal anomalies need to be actively addressed. A combination of radiologic, pathologic, genetic and molecular investigation prenatally as well as postnatally is required to classify a specific congenital skeletal dysplasia. Once the genetic make-up of fetal skeletal dysplasia is deciphered, a meaningful genetic counselling could be offered for future pregnancies of affected families. We describe a case of primigravida diagnosed with fetal unilateral upper limb AMD on antenatal ultrasound done at early second trimester. The radius and ulna of left upper limb were abnormally short (less than 5th centile of the mean for that gestational age). The left hand was also hypoplastic. Rest of the sonographic anomaly scan was normal. To the best of our knowledge, AMD limited to unilateral upper limb diagnosed antenatally as an isolated finding is not described in the medical literature so far.

Bioarchaeology and evidence of violence from a precolonial later stone age communal burial in South Africa.

This study reports on the bioarchaeology and evidence of interpersonal violence in a group of archaeological skeletons found near Ladismith, Western Cape, South Africa. The co-mingled skeletal remains derive from at least ten individuals of varying ages and both sexes. Overlapping radiocarbon dates on three individuals place them in the first half of the 15th century CE, pre-dating first European contact at the end of that century. Three juvenile crania have perimortem perforations, the locations of which indicate violent deaths. The sizes and shapes of the lesions suggest impact by a blade at least 110mm long and 50mm wide but with edges only 2mm thick. Based on these dimensions, we hypothesise that this was a metal-tipped spear. The nearest metal-working communities at this time lived approximately 500 km away, implying long-distance trade or exchange. δ13C, δ15N and 87Sr/86Sr values indicate that this was a heterogenous group of individuals who had spent their early lives in different locations and consumed varied diets, who had come together and were living in or travelling through the Ladismith area at the time of their deaths. This finding extends the timeframe and location for the practice of communal burial in the Holocene of southern Africa and provides additional support for the hypothesis that communal burials in this region tend to be associated with violence.

A novel murine syngeneic CD8 peripheral T-cell lymphoma model with preclinical applications

Peripheral T-cell Lymphoma (PTCL) represents a heterogenous group of aggressive non-Hodgkin Lymphomas with poor prognostic outcomes and limited treatment options. The development and refinement of therapeutic strategies for PTCL are impeded by a paucity of reliable preclinical models that accurately mimic the disease’s pathophysiology. There is a dire need for more physiologically relevant models for PTCL. Here we describe a spontaneousCD8+ peripheral T-cell lymphoma cell line (LM-23) derived from a 12-week-old female Balb/cJ mouse. Both intravenous and subcutaneous administration of this cell line to syngeneic Balb/cJ mice resulted in rapid establishment of tumor growth. CHOP and anti-PD1 treatment both displayed no benefit to mice in regulating tumor growth. Such results along with its phenotypic characteristics, rapid growth, and metastatic behavior in syngeneic mice highlight its value in studying the elusive disease and discovery of novel therapeutics.

Current Landscape of Chronic Inflammatory Dermatoses: Where We Are and Where We Are Heading

Chronic inflammatory dermatoses represent a heterogeneous group of skin disorders that are often characterized by persistent and relapsing inflammation, with complex underlying pathomechanisms [...]

Myeloproliferative Neoplasms and Cardiovascular Disease: A Review.

Myeloproliferative neoplasms (MPN) are a heterogenous group of disorders of clonal hematopoiesis characterized by constitutive activation of the JAK/STAT signaling pathway leading to proliferation of blood cells. Cardiovascular disease (CVD) contributes significantly to the morbidity and mortality of patients with MPN. Particularly well-known CVD complications of MPNs are arterial and venous thrombotic events. However, MPNs are also associated with other forms of CVD including atrial fibrillation, heart failure, and pulmonary hypertension. Recent studies have characterized outcomes of patients with MPN and CVD, including acute myocardial infarction (AMI), heart failure, atrial fibrillation, and pulmonary hypertension. Additionally, optimal cardiovascular disease prevention strategies in patients with MPN are not yet clear. Further investigation is warranted to improve CVD outcomes in patients with MPN. Clinicians should be aware of cardiovascular complications of MPN, including thrombotic as well as non-thrombotic complications (heart failure, arrhythmias, pulmonary hypertension).

Congenital Adrenal Hyperplasia: A Review of Current Knowledge and Future Directions

Introduction: Congenital adrenal hyperplasia (CAH) is a group of diseases in which genetic defects occur that disturb the synthesis of cortisol. The most common variant of CAH (95%-99%) is caused by 21-hydroxylase deficiency as a result of mutations in the CYP21A2 gene and is one of the most common monogenic diseases. CAH is characterized by androgen overproduction along with variable degrees of cortisol and aldosterone deficiency. Age at diagnosis can provide some information about the underlying mutations, with those diagnosed at birth/early infancy being at greater risk of developing serious enzyme defects. Classic and non-classical forms of this disorder have been described in the literature. CAH diagnosis is based on the clinical presentation, hormonal panel, Adrenocorticotropic Hormone (ACTH) stimulation test, and genetic testing. The main goals of treatment for congenital adrenal hyperplasia are glucocorticoid/mineralcorticoid supplementation, control of high adrenal androgen levels, fertility control, genetic counseling, and optimization of patients’ quality of life. Purpose of the work: This study aims to review and characterize the clinical and pathophysiological aspects of congenital adrenal hyperplasia. Materials and methods: A comprehensive analysis of research papers available on PubMed, Google Scholar, Web of Science, Embase and Scopus was undertaken using the searchterms encompassing the following keywords: congenital adrenal hyperplasia, 21-hydroxylase deficiency, CYP21A2 Results: Congenital adrenal hyperplasia is a heterogeneous group of genetic disorders that can lead to serious and even fatal complications in the form of adrenal crisis. Therefore, screening tests and early diagnosis are crucial and can save the lives of newborns. Treatment should be individualized and allow patients to achieve normal growth, sexual development, fertility and a better quality of life.

Bone Marrow Stromal Cells Enhance Differentiation of Acute Myeloid Leukemia Induced by Pyrimidine Synthesis Inhibitors.

Acute myeloid leukemia (AML) is a heterogeneous group of hematologic malignancies characterized by differentiation arrest, high relapse rates, and poor survival. The bone marrow (BM) microenvironment is recognized as a critical mediator of drug resistance and a primary site responsible for AML relapse. Our previous study reported that 5-aminoimidazole-4-carboxamide ribonucleoside (AICAr) induces AML cell differentiation by inhibiting pyrimidine synthesis and activating Checkpoint kinase 1. While the protective effect of BM stroma on leukemia cells in response to cytotoxic drugs is well-documented, its effect on AML differentiation remains less explored. In this study, we investigated the impact of stromal cell lines and primary mesenchymal stromal cells (MSCs) on AML cell line differentiation triggered by AICAr and brequinar, a known dihydroorotate dehydrogenase (DHODH) inhibitor. Our findings indicate that the mouse MS-5 stromal cell line, known for its cytoprotective effects, does not inhibit AML cell differentiation induced by pyrimidine synthesis inhibitors. Interestingly, AICAr caused morphological changes and growth arrest in MS-5 stromal cells via an AMPK-dependent pathway. Human stromal cell lines HS-5 and HS-27, as well as primary MSCs isolated from patient bone marrow, were superior in promoting AML differentiation compared to mouse cells in response to AICAr and brequinar, with the inhibitors not significantly affecting the stromal cells themselves. In conclusion, our study highlights the supportive role of human BM MSCs in enhancing the differentiation effects of pyrimidine synthesis inhibitors on AML cells, suggesting that AML treatment strategies focusing on differentiation rather than cell killing may be successful in clinical settings.

Rhabdomyosarcoma of the skull with EWSR1 fusion and ALK and cytokeratin expression: a case report.

Rhabdomyosarcoma (RMS) comprises of heterogeneous group of neoplasms that occasionally express epithelial markers on immunohistochemistry (IHC). We herein report the case of a patient who developed RMS of the skull with EWSR1 fusion and anaplastic lymphoma kinase (ALK) and cytokeratin expression as cytomorphologic features. A 40-year-old man presented with a mass in his forehead. Surgical resection was performed, during which intraoperative frozen specimens were obtained. Squash cytology showed scattered or clustered spindle and epithelioid cells. IHC revealed that the resected tumor cells were positive for desmin, MyoD1, cytokeratin AE1/ AE3, and ALK. Although EWSR1 rearrangement was identified on fluorescence in situ hybridization, ALK, and TFCP2 rearrangement were not noted. Despite providing adjuvant chemoradiation therapy, the patient died of tumor progression 10 months after diagnosis. We emphasize that a subset of RMS can express cytokeratin and show characteristic histomorphology, implying the need for specific molecular examination.

Abstract PR-17: Genomic and transcriptomic characterization of pancreatic cancer patients on the PASS-01 trial

Abstract Overall survival for patients with advanced PDAC remains less than 1 year. Biomarkers are needed to select chemotherapy regimens, either alone or in combination with novel agents. PASS-01 compared mFOLFIRINOX and Gemcitabine/nab-Paclitaxel in a phase II randomised control trial while prospectively exploring tissue, liquid and organoid biospecimens to interrogate putative biomarkers of chemotherapy response and resistance. Methods PASS-01 was conducted across 6 sites in North America. Patients with de novo metastatic disease and a lesion amenable to core biopsy were included. Cases with germline pathogenic variants in BRCA1/2 or PALB2 were excluded. Up to 6 core biopsies were obtained with priorities for clinical diagnosis, patient derived organoids (PDOs), and whole genome and transcriptome sequencing (WGTS). WGTS were performed at a single site following laser capture microdissection. WGS reports were clinically (CAP) accredited and annotated mutations, copy number alterations, mutational signatures, TMB and structural variant patterns. KRAS allelic states were documented with major imbalances in mutant KRAS (KRASmaj) defined as mutant: WT copy number &amp;gt;3. Transcriptomic subtypes (classical vs. basal-like) were classified as previously described (Moffitt et al., 2015). WGTS results were discussed at a molecular tumor board with PDO pharmacotyping to determine best second line options. Results: 160 patients were included in the intention to treat population, of these WGS was available in 127 (79%) and additional NGS reports in 20 (13%). RNA-seq was successful in 119 (74%) and the basal-like subtype accounted for 29% and was associated with inferior outcomes. KRASm were evident in 91% and KRASG12D represented 45%. Tumor suppressors TP53, CDKN2A and SMAD4 were lost in 81%, 76% and 39% respectively. MTAP deletion was present in 40%, largely synonymous with CDKN2A deletions. Commonly co-altered genes in the dataset included epigenetic regulators (ARID1A, KMT2C, KDM6A) and TGFBR2. KRASmaj was present in 30% of cases and polyploid tumors in 50%. 50% of basal-like PDAC harboured KRASmaj compared to 22% of classical PDAC, p&amp;lt;0.01. Dominant signatures (SBS) included age related SBS1, 5 and 8. Additionally, we saw a prevalence of SBS17 and APOBEC SBS2/13, signatures which occurred more frequently compared to a similarly characterised resected cohort. Unstable genotypes were present in 24% with somatic-HRD evident in 3%. Of KRASWT PDAC, 58% harboured class I-II BRAF variants. KRAS WT PDAC had fewer co-mutations and in one case where an NGS report did not find a driver, a novel fusion in SLC4A4-RASGRF2 was identified. 28 molecular tumor boards took place throughout the trial influencing 50% obtaining a 2nd-line treatment. Conclusion: The PASS-01 cohort exhibits a heterogeneous group of genotypes and molecular subgroups. Certain mutational processes are more evident in advanced compared to resected PDAC. The impact of subgroups on survival and chemotherapy response is ongoing with a planned data lock on July 15th. Results will be presented at the meeting. Citation Format: Grainne M O'Kane, Gunho Jang, Trevor J Pugh, Julie Wilson, Stephanie Ramotar, Daniel A King, Dan Laheru, Ken H Yu, Kimberly J Perez, Amber Habowski, Erica S Tsang, Robert C Grant, Andrew J Aguirre, Raymond W-J Jang, Craig E Devoe, Eileen M O'Reilly, Anna Dodd, Brian M Wolpin, Xiang Y Ye, Elizabeth M Jaffee, David Tuveson, Steven Gallinger, Jennifer J Knox, Faiyaz Notta. Genomic and transcriptomic characterization of pancreatic cancer patients on the PASS-01 trial [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr PR-17.

Identification of novel likely pathogenic variant in CDH23 causing non-syndromic hearing loss, and a novel variant in OTOGL in an extended Iranian family

BackgroundSensorineural hearing loss (SNHL) is a clinically and genetically heterogeneous group of disorders of the auditory system. SNHL can occur as a symptom in more than 400 syndromes, and mutations in more than 150 genes can lead to SNHL. Mutations in the GJB2 and GJB6 genes are among the most common causes of SNHL worldwide. Mutations in Cadherin 23 (CDH23) can cause Usher syndrome and/or non-syndromic hearing loss (NSHL).Material and methodsIn this study, the Whole Exome Sequencing (WES) was used to detect the cause of hearing loss in a large consanguineous Iranian family with two patients. All family members underwent a thorough Genotype–phenotype correlation assessment and co-segregation analysis to understand the inheritance pattern within the family. The candidate variants were further confirmed by Sanger sequencing. In addition, in silico analysis was performed to predict the functional impact of the variants; the interpretation of the variants was performed in accordance with the American College of Medical Genetics (ACMG) guidelines.ResultsWES results identified two novel variants, a homozygous missense variant in CDH23 (c.2961T > G) and a heterozygous splice site variant in OTOGL that was compatible with the autosomal recessive pattern of inheritance. Bioinformatics studies confirmed the pathogenic effects of novel variants. The c.2961T > G variant was classified as likely pathogenic.ConclusionsThe novel identified variant in the CDH23 was the cause of congenital profound progressive form of HL. Samples were not available from the second family to distinguish which variant is responsible for the molecular pathology of the disease. Further studies and functional examinations are suggested for investigating the role of OTOGL: c. 1863-1G > T in deafness.