Chromosome 11q13 Research Articles

Abstract 2819: Novel drug resistant CDX models for anti-cancer drugs discovery

Abstract Oncogene BRAF is located on chromosome 7q34, consisting of 766 amino acids and 22 exons, encoding a serine/threonine protein kinase belonging to the RAF family and plays a critical role in the MAPK signaling pathway. The mutation of BRAF was documented in nearly 8% of all human cancers including melanoma (60%), thyroid (60%), and lung adenocarcinoma (10%). The most common mutation of BRAF is V600E (Class I), which was found in more than 70% in these cancers. Despite the clinical success of approved small molecule inhibitors of BRAF V600E (vemurafenib, dabrafenib and encorafenib), this remains an area of unmet medical need because of primary or acquired drug resistance. The construction of BRAF drug-resistant cell lines plays a pivotal role in cancer research. It serves as a crucial tool for discovery of the mechanisms of drug resistance. In this study, we have developed a systematic approach for constructing drug-resistant cell lines, inducing resistance through the gradual escalation of drug concentrations. The validation of drug resistance involves morphological recordings of parent and drug-resistant cell lines, drug resistance index in vitro through IC50 measurements and in vivo through the inhibition of tumor growth (TGI) which compare to those in the parental cell line. We successfully established Vemurafenib and Dabrafenib resistant A375 cell lines (A375 Vemurafenib R, A375 Dabrafenib R) with 21 and 31.5 folds of resistance index, respectively. The in vivo drug resistance efficacy was also tested by implanting Vemurafenib resistant cells subcutaneously into NOD-SCID mice and showed that A375 Vemurafenib R exhibited robust tolerance to 50 mg/kg Vemurafenib treatment (P.O.21 days, 50mpk, TGI=17.4%), whereas the parental cells were nearly completely inhibited (P.O.21 days, 50mpk, TGI=92.3%). In addition, single-cell sequencing of A375 Vemurafenib R revealed significant gene expression differences in the MAPK and EGFR signaling pathways, aiding in the identification of new targets, and signaling pathways associated with drug resistance, thereby providing potential targets for new drug development. Citation Format: Hai-Ting Dai, Tie-Jun Bing, Zhi-Da An, Jie Yang, Tian-Yu Pang, Jia-Wei Gao, Yun-Yi Bo, Wen-Jen Yu. Novel drug resistant CDX models for anti-cancer drugs discovery [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2819.

Abstract 1992: A novel RB1 E3 ligase TRIM37 contributes to palbociclib resistance in breast cancer

Abstract The tripartite motif-containing 37 (TRIM37) is a RING finger E3 ubiquitin ligase and is a poor prognostic factor in breast cancer patients. The gene is located in chromosome 17q23, a region amplified in up to 40% of breast cancers. We observed that activation of androgen receptor (AR) could induce resistance to the CDK4/6 inhibitor Palbociclib, the mechanism yet to be clarified. ChIP-sequencing data suggested that AR binds to the TRIM37 promoter, with AR activation resulting in TRIM37 expression. We hypothesized that TRIM37 might be involved in Palbociclib resistance. Using an ER+ve cell line MCF7 and a TNBC cell line MDA-MB 453, we found that overexpression of TRIM37 could induce Palbociclib resistance. TRIM37 overexpression resulted in RB1 protein downregulation, which is the primary downstream target of CDK4/6, while TRIM37 knockdown enhanced RB1 protein expression. Ubiquitination assay demonstrated TRIM37 overexpression increased the level of RB1 protein ubiquitination. The co-immunoprecipitation (Co-IP) assay confirmed that TRIM37 protein could interact with the RB1 protein. These results suggest that TRIM37 could be the E3 ligase that regulates RB1 degradation. Various deletion mutants of TRIM37 were cloned for Co-IP experiments between these mutants and RB1. Results show that the MATH and c-terminal domains of TRIM37 was the essential region for the interaction. Overexpression of the mutant with the TRIM37 MATH and c-terminal domains (TRIM37-MATH/C) could enhance RB1 protein level. This might be due to competition of TRIM37-MATH/C with wild-type TRIM37 for RB1 binding. Our findings suggest TRIM37 is a novel RB1 E3 ligase, and it binds to the RB1 protein via the MATH and C-terminal domains to regulate protein degradation. Our study also suggests that high expression of TRIM37 mediated by AR activation could deplete RB1, which is the target of Palbociclib, eventually leading to resistance. These findings are supportive of the contribution of AR activation to Palbociclib resistance. Citation Format: Chanping You, Ho Tsoi, Pui Sum Man, Larry Ka Yue Chow, Wei Dai, Ui Soon Khoo. A novel RB1 E3 ligase TRIM37 contributes to palbociclib resistance in breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1992.

Abstract 473: PVT1 exon 9 overexpression induces AR null phenotype and cellular reprogramming in prostate cancer

Abstract Plasmacytoma variant translocation 1 (PVT1) is an oncogenic long-noncoding RNA (lncRNA) gene located directly downstream of MYC on chromosome 8q24. PVT1 is an oncogene overexpressed in prostate cancer (PCa) and can promote oncogenesis by altering gene expression directly or acting as a noncoding RNA sponge. Beyond functioning as a lncRNA, PVT1 gene encodes six microRNAs that each have independent functions. Our group identified overexpression of PVT1 exon 9 in PCa samples derived from men of African Ancestry and overexpression may explain why this population group experiences more aggressive disease. We overexpressed PVT1 exon 9 in RWPE1 prostate epithelial cells (RWPE1_ex9) and found enhanced migration and invasion compared to empty vector (RWPE1_ev). Implantation of RWPE1_ex9 cells into mice led to the formation of tumors with the neuroendocrine PCa (NEPC) phenotype that was histopathologically confirmed. RNA-sequencing analysis of PVT1 exon 9 overexpression showed significant (p-value < 0.05) upregulation of 141 genes. The majority of pathways impacted by PVT1 exon 9 overexpression were interferon type 1 signaling (RSAD2, CMPK2), developmental NOTCH signaling (HES7), cargo-transport (STX16) and tumor microenvironment promoting factors (HS3ST3A1). We found loss of androgen receptor (AR) expression at mRNA and protein levels in RWPE1_ex9 cells, a hallmark of NEPC, which further supports our hypothesis that PVT1 exon 9 overexpression plays a role in NEPC development. Validation of RNA-sequencing confirmed upregulation of RSAD2, CMPK2, STX16, HES7 and HS3ST3A1 within RWPE1_ex9 cells compared to RWPE1_ev and RWPE1 wild-type, suggestive of cellular reprogramming of prostate epithelial cells. We further analyzed expression profile in a novel circulating tumor cell model of castration-resistant 22RV1 cells (C22OH) and found enhanced expression of PVT1 exon 9, suppression of AR, phosphorylation of AR serine residue 308 and enhanced CDK11 activity compared to the primary 22RV1 cell line T22OH suggestive of a cell-cycle mediated regulatory mechanism. We further found enhanced expression of chromogramin A in the C22OH cell line, a marker of NEPC. These results suggest PVT1 exon 9 overexpression may play a critical role in NEPC development from normal epithelial cells via cellular reprogramming as well as facilitating a transition to NEPC from a castration resistant phenotype. PVT1 exon 9 may be a useful predictive biomarker that can identify populations which are likely to have disease progression from castration resistance to NEPC and further highlights the need to identify therapeutic strategies to target PVT1 exon 9 overexpression. Citation Format: Rachel E. Sexton-Bonacci, Chinedum Udekwu, Baris Boylu, Olorunseun O. Ogunwobi. PVT1 exon 9 overexpression induces AR null phenotype and cellular reprogramming in prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 473.

Abstract 6977: ETV6 is an unexplored partner of the Chr.8 q24.3 amplicon-embedded immortalizing oncogene TONSL in tumorigenesis

Abstract Approximately 20% of breast cancers exhibit recurring genomic amplification involving chromosome 8q24.3. In our previous study, we identified the Tonsoku-like DNA repair protein (TONSL) within this amplicon as an immortalizing oncogene of breast epithelial cells, that can promote Estrogen Receptor-positive (ER+) breast adenocarcinomas when combined with other breast cancer-associated oncogenes. Our findings indicated that TONSL-amplified breast cancer cells are dependent on TONSL for tumor growth and exhibited deregulated homologous recombination and cell cycle pathways. High levels of TONSL in primary breast cancers, particularly ER+ breast cancers, were associated with poor outcomes. Although TONSL itself is not druggable, owing to its lack of enzymatic activity, molecules that disrupt the TONSL interactome can be developed. Towards this goal, we performed immunoprecipitation (IP) with TONSL antibody using protein lysates from TONSL-immortalized primary breast epithelial cells and subjected the immunoprecipitates to mass spectrometry. We identified several proteins selectively enriched with the TONSL antibody, the most significant of which was ETS variant transcription factor 6 (ETV6). ETV6 is a modular protein consisting of a C-terminal DNA-binding ETS domain and N-terminal point (PNT) domain and is known to play a role as a transcriptional repressor during embryonic development and hematopoiesis. We confirmed these data by IP followed by western blot analysis of primary breast epithelial cells and TONSL amplified MDA-MB-436. Furthermore, we utilized ClusPro to model the TONSL-ETV6 interaction and predicted that the TONSL’s ankyrin repeats docks onto ETV6’s PNT in a favorable manner. To investigate the functional significance of this interaction, we evaluated ETV6-regulated genes using RNA-seq. Our analysis revealed that ETV6-regulated genes were downregulated following TONSL knockdown and vice versa. Most ETV6 target genes affected upon TONSL manipulation are involved in Epithelial-Mesenchymal Transition (EMT), particularly TWIST1, SNAI2 and ZEB1. Previous studies have demonstrated a role of ETV6 in limiting EMT by repressing the expression of EMT-associated transcription factors. Our findings revealed that TONSL overexpression in primary breast epithelial cells led to a significant increase in these EMT gene expression, whereas TONSL knockdown in MDA-MB-436 cells resulted in a moderate decrease. These findings suggest that TONSL binds to ETV6 and restricts its ability to bind to the regulatory regions of EMT-associated genes, leading to a transcriptional surge of EMT-associated genes leading to tumor progression. Further studies will contribute to our understanding of the role of the chr.8q24.3 amplicon, specifically the TONSL gene, in initiating/promoting breast tumorigenesis and the development of novel drugs that target the TONSL interactome. Citation Format: Aditi S. Khatpe, Emma Doud, Amber Mosely, Kathy D. Miller, Harikrishna Nakshatri. ETV6 is an unexplored partner of the Chr.8 q24.3 amplicon-embedded immortalizing oncogene TONSL in tumorigenesis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6977.

Abstract 2818: Investigating the role of TNIK in the pathogenesis of lung squamous cell carcinoma

Abstract Lung squamous cell carcinoma (LSCC) is the second most prevalent type of lung cancer with no FDA-approved targeted therapies. Platinum-based chemotherapy and immunotherapy remain the cornerstone of current treatments for advanced LSCC, and the 5-year survival rate is less than 10%. Despite abundant knowledge of the mutational landscape of LSCC, there is a paucity of effective targeted therapies. Amplification of chromosome 3q26 is the most common genomic alteration in LSCC and this leads to the overexpression of oncogenic kinases like TNIK. TNIK amplification occurs in approximately 50% of LSCC cases and is associated with tumorigenesis and therapy resistance in other cancers. Recent studies showed that TNIK maintains the survival of LSCC cells and drives LSCC progression. Furthermore, inhibiting the kinase eradicates tumor growth in TNIK-high preclinical models. These findings highlight the potential of TNIK as a therapeutic target in a subset of LSCC patients with 3q amplification. However, one major limitation of previous studies is the lack of animal models with squamous histology and patient-relevant genotypes. Therefore, we have created a novel conditional TNIK-overexpressing genetically engineered mouse model (GEMM) to better understand the roles of TNIK in tumor progression and therapy resistance in LSCC and elucidate mechanisms underlying LSCC pathogenesis. We are also producing a novel TNIK-overexpressing LSCC GEMM based on the simultaneous activation of KrasG12D and deletion of Fbxw7 (KF model). We will present validation studies such as histological and molecular profiling of our conditional TNIK GEMM and initial data on the TNIK overexpressing LSCC transgenic mouse model (KF (LSCC control) vs KF-TNIK (LSCC-TNIK)). Citation Format: Jin Hee Chang, Dipanwita Dutta Chowdhury, Danielle N. Council, Triet Nguyen, Shreya Jagtap, Aaron Chan, Muhammad Ajmal Khan, Nick Connis, Pedro Torres-Ayuso, John Brognard, Moahmmad Rezaee, Audrey Lafargue, Christine Hann, Phuoc T. Tran. Investigating the role of TNIK in the pathogenesis of lung squamous cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2818.

Abstract 2640: HBI-2375, a first-in-class IND ready selective MLL1-WDR5 inhibitor, retains desirable preclinical characteristics in solid tumors and in leukemias to be pursued in clinical studies

Abstract MLL1 (mixed lineage leukemia1) interaction with WDR5 (WD repeat domain 5) is critical for its histone methyl transferase (HMT) activity leading to transcriptional regulation of gene expression. MLL1 dysregulation such as its translocation at chromosome 11q23 results in generation of MLL1 fusion genes and leukemia development. Additionally, recent studies indicated a role for MLL1-WDR5 interaction in solid tumors progression via directly affecting cancer cells or by suppression of tumor immunity. Therefore, MLL1-WDR5 interaction is an important target in the discovery of anti-cancer drugs for both leukemia and solid tumors. We recently identified HBI-2375 as a selective inhibitor of MLL1-WDR5 interaction. HBI-2375 showed potent inhibition of WDR5 (IC50: 4.48nM) in biochemical assay and inhibited MV4-11 cellular proliferation (average IC50: 3.17µM) in CTG assays. In addition, HBI-2375 was stable in liver S9 and whole blood, with moderate to high plasma protein binding rates in multiple species, and acceptable hERG (IC50: 17µM). Furthermore, HBI-2375 displayed reasonable oral PK properties (Cmax, T1/2, AUC, and F%) in mouse, rat and dog and showed good safety profile in GLP tox studies. In pharmacology studies HBI-2375 showed significant dose dependent anti-tumor activity in MV4-11 AML model along with reduction in methylation of H3K4 in the tumors harvested from the treated animals demonstrating the targeted disruption of HMT activity in cancer cells by HBI-2375. Furthermore HBI-2375 in combination with PD-1 mAb significantly inhibited tumor growth in MC38, colorectal tumor model, and in 3LL lung carcinoma syngeneic tumor models. Flow cytometry and IHC showed significant increase in the infiltration of CD8+ CTLs in the combination group further providing immune-driven mechanisms for greater efficacy of combination therapy. Gene expression analysis also identified genes that are involved in promoting immune system activity in the combination group. Tissue distribution studies also showed greater accumulation of HBI-2375 in brain tissue indicative of a potential to target glioma and glioblastoma in clinical studies. Therefore, HBI-2375 represents a first-in-class MLL1-WDR5 inhibitor with promising characteristics for future testing in the clinic. Citation Format: Farbod Shojaei, Che Fang, Jill M. Ricono, Mireille Gillings. HBI-2375, a first-in-class IND ready selective MLL1-WDR5 inhibitor, retains desirable preclinical characteristics in solid tumors and in leukemias to be pursued in clinical studies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2640.

KLIPPEL FEIL SYNDROME AND ASSOCIATED ANOMALIES

Introduction: Klippel-Feil syndrome (KFS) is a rare genetic disorder characterized by abnormal the development of the cervical spine, which leads to the fusion of two or more cervical vertebrae. Incidence is 1:40 000 - 42 000. Inheritance is usually autosomal dominant. The gene mutation is most often found on the long arm of chromosome 8q22.1.The syndrome was first described by French physicians, Maurice Klippel and André Feil in 1912 with the classic clinical triad of manifestations consisting of a low posterior hairline, short neck, and limited neck range of motion. There may be skin folds on the neck - Pterygium colli, and the shoulder blades are high - Sprengel Deformity. Scoliosis is often present. Accompanying, hidden anomalies may be more important than neck deformity. A clinical finding with an objective examination is sufficient to suspect this syndrome. And then additional diagnostic methods are applied. Surgical intervention is carried out in the event of instability on the spine with the aim of eliminating it, as well as correcting scoliosis. Therapy of accompanying anomalies - kidney, neurological disorders, hearing disorders. Physical therapy is also recommended, which gives modest results. The life span of people with Klippel-Feil syndrome is shortened due to frequent anomalies of the internal organs. Case report: The paper presents a girl aged 10 years and 10/12 months. Pronounced hypertelorism. On the upper lip, a scar after cleft lip and palate surgery, left. Teeth carious, irregularly arranged. Neck short with pterygium. Low hairline. Pronounced scoliosis. High position of the shoulder blades. Abdominal ultrasound shows agenesis of the right kidney. IVP - the right kidney is not shown, the left kidney is compensatory enlarged. A diagnosis of Klippel Feil syndrome was made in a tertiary institution. Parents refuse further tests and treatment. Conclusion: In every child with Klippel-Feil syndrome, further examination and detection of accompanying, hidden anomalies that may be more important than the neck deformity is necessary.

CLLU1 as an emerging biomarker in chronic lymphoid leukemia.

CLLU1, a disease-specific gene associated with chronic lymphoid leukemia (CLL), is located on chromosome 12q22. Previous studies considered CLLU1 to be a non-coding RNA; however, recent research has discovered that its coding sequence region possesses the potential to encode a short peptide similar to interleukin-4. Remarkably, abnormally elevated expression of CLLU1 has only been detected in chronic lymphoid leukemia among all hematological cancers. High CLLU1 expression often indicates more malignant pathological features and an unfavorable prognosis for patients. Importantly, the expression level of CLLU1 remains unaffected by the passage of time or therapeutic interventions, thus rendering it a novel prognostic marker. This article provides a comprehensive summary of relevant research findings on CLLU1 in the context of CLL prognosis and clinical applications, aiming to guide subsequent theoretical and clinical investigations in this field.

Whole F8 gene sequencing identified pathogenic structural variants in the remaining unsolved patients with severe hemophilia A

BackgroundNo F8 genetic abnormality is detected in approximately 1% to 2% of patients with severe hemophilia A (HA) using conventional genetic approaches. In these patients, deep intronic variation or F8 disrupting genomic rearrangement could be causal. ObjectivesThe study aimed to identify the causal variation in families with a history of severe HA for whom genetic investigations failed. MethodsWe performed whole F8 gene sequencing in 8 propositi. Genomic rearrangements were confirmed by Sanger sequencing of breakpoint junctions and/or quantitative polymerase chain reaction. ResultsA structural variant disrupting F8 was found in each propositus, so that all the 815 families with a history of severe HA registered in our laboratory received a conclusive genetic diagnosis. These structural variants consisted of 3 balanced inversions, 3 large insertions of gained regions, and 1 retrotransposition of a mobile element. The 3 inversions were 105 Mb, 1.97 Mb, and 0.362 Mb in size. Among the insertions of gained regions, one corresponded to the insertion of a 34 kb gained region from chromosome 6q27 in F8 intron 6, another was the insertion of a 447 kb duplicated region from chromosome 9p22.1 in F8 intron 14, and the last one was the insertion of an Xq28 349 kb gained in F8 intron 5. ConclusionAll the genetically unsolved cases of severe HA in this cohort were due to structural variants disrupting F8. This study highlights the effectiveness of whole F8 sequencing to improve the molecular diagnosis of HA when the conventional approach fails.

Identification of Genetic Variants for Risk Prediction and Early Diagnosis of Age-Related Macular Degeneration in the Taiwanese Population.

Age-related macular degeneration (AMD) is the leading cause of blindness in the elderly worldwide. The prevalence and phenotypes of AMD differ among populations, including between people in Taiwan and other regions. We performed a genome-wide association study to identify genetic variants and to develop genetic models to predict the risk of AMD development and progression in the Taiwanese population. In total, 4039 patients with AMD and 16,488 non-AMD controls (aged ≥ 65 years) were included. We identified 31 AMD-associated variants (p < 5 × 10-8) on chromosome 10q26, surrounding PLEKHA1-ARMS2-HTRA1. Two genetic models were constructed using the clump and threshold method. Model 1 included the single nucleotide polymorphism rs11200630 and showed a 1.31-fold increase in the risk of AMD per risk allele (95% confidence interval (CI) = 1.20-1.43, p < 0.001). In model 2, 1412 single-nucleotide polymorphisms were selected to construct a polygenic risk score (PRS). Individuals with the top 5% PRS had a 1.40-fold higher AMD risk compared with that of individuals with a PRS in the bottom quartile (95% CI = 1.04-1.89, p = 0.025). Moreover, the PRS in the upper quartile was related to a decreased age at AMD diagnosis by 0.62 years (95% CI = -1.15, -0.09, p = 0.023). Both genetic models provide useful predictive power for populations at high risk of AMD, affording a basis for identifying patients requiring close follow-up and early intervention.

Congenital Heart Defects in Patients with Molecularly Confirmed Sotos Syndrome.

Sotos syndrome is an autosomal dominant condition characterized by overgrowth with advanced bone age, macrodolicocephaly, motor developmental delays and learning difficulties, and characteristic facial features caused by heterozygous pathogenetic variants in the NSD1 gene located on chromosome 5q35. The prevalence of heart defects (HDs) in individuals with Sotos syndrome is estimated to be around 15-40%. Septal defects and patent ductus arteriosus are the most commonly diagnosed malformations, but complex defects have also been reported. The aim of our study was to analyze the prevalence of HD, the anatomic types, and the genetic characteristics of 45 patients with Sotos syndrome carrying pathogenetic variants of NSD1 or a 5q35 deletion encompassing NSD1, who were followed at Bambino Gesù Children's Hospital in Rome. Thirty-nine of the forty-five patients (86.7%) had a mutation in NSD1, while six of the forty-five (13.3%) had a deletion. Most of the patients (62.2%, 28/45) were male, with a mean age of 14 ± 7 years (range 0.2-37 years). A total of 27/45 (60.0%) of the patients had heart defects, isolated or combined with other defects, including septal defects (12 patients), aortic anomalies (9 patients), mitral valve and/or tricuspid valve dysplasia/insufficiency (1 patient), patent ductus arteriosus (3 patients), left ventricular non-compaction/hypertrabeculated left ventricle (LV) (4 patients), aortic coarctation (1 patient), aortopulmonary window (1 patient), and pulmonary valve anomalies (3 patients). The prevalences of HD in the two subgroups (deletion versus intragenic mutation) were similar (66.7% (4/6) in the deletion group versus 58.91% (23/39) in the intragenic variant group). Our results showed a higher prevalence of HD in patients with Sotos syndrome in comparison to that described in the literature, with similar distributions of patients with mutated and deleted genes. An accurate and detailed echocardiogram should be performed in patients with Sotos syndrome at diagnosis, and a specific cardiological follow-up program is needed.

5G2 mutant mice model loss of a commonly deleted segment of chromosome 7q22 in myeloid malignancies

Monosomy 7 and del(7q) are among the most common and poorly understood genetic alterations in myelodysplastic neoplasms and acute myeloid leukemia. Chromosome band 7q22 is a minimally deleted segment in myeloid malignancies with a del(7q). However, the rarity of “second hit” mutations supports the idea that del(7q22) represents a contiguous gene syndrome. We generated mice harboring a 1.5 Mb germline deletion of chromosome band 5G2 syntenic to human 7q22 that removes Cux1 and 27 additional genes. Hematopoiesis is perturbed in 5G2+/del mice but they do not spontaneously develop hematologic disease. Whereas alkylator exposure modestly accelerated tumor development, the 5G2 deletion did not cooperate with KrasG12D, NrasG12D, or the MOL4070LTR retrovirus in leukemogenesis. 5G2+/del mice are a novel platform for interrogating the role of hemopoietic stem cell attrition/stress, cooperating mutations, genotoxins, and inflammation in myeloid malignancies characterized by monosomy 7/del(7q).

L-2-hydroxyglutaric aciduria: a report of clinical, radiological, and genetic characteristics of two siblings from Egypt

ABSTRACT L-2-hydroxyglutaric aciduria (L-2-HGA) is a rare autosomal recessive disease characterized by elevated levels of hydroxyglutaric acid in the body fluids and brain with abnormal white matter. We present two siblings with psychomotor retardation and quadriparesis. Their brain imaging showed diffuse bilateral symmetrical involvement of the cerebral cortex, white matter, basal ganglia and cerebellum. The whole exome sequence studies revealed a homozygous likely pathogenic variant on chromosome 14q22.1 (NM_024884.2: c.178G > A; pGly60Arg) in the gene encoding for L-2-hydroxyglutarate dehydrogenase (L2HGDH) (OMIM #236792). Therefore, using the L2HGDH gene study is beneficial for L2HGA diagnosis.

NG2 Molecule Expression in Acute Lymphoblastic Leukemia B Cells: A Flow-Cytometric Marker for the Rapid Identification of KMT2A Gene Rearrangements.

B-lineage acute lymphoblastic leukemias (B-ALL) harboring rearrangements of the histone lysine [K]-Methyltransferase 2A (KMT2A) gene on chromosome 11q23 (KMT2A-r) represent a category with dismal prognosis. The prompt identification of these cases represents an urgent clinical need. Considering the correlation between rat neuron glial-antigen 2 (NG2) chondroitin-sulfate-proteoglycan molecule expression and KMT2A-r, we aimed to identify an optimized cytofluorimetric diagnostic panel to predict the presence of KMT2A-r. We evaluated 88 NG2+ B-ALL cases identified with an NG2 positivity threshold >10% from a cohort of 1382 newly diagnosed B-ALLs referred to the Division of Hematology of 'Sapienza' University of Rome. Eighty-five of 88 (96.6%) NG2+ B-ALLs harbored KMT2A-r and were mainly pro-B ALL (77/85; 91%). Only 2 B-ALLs with KMT2A-r showed NG2 expression below 10%, probably due to the steroid therapy administered prior to cytofluorimetric analysis.Compared to KMT2A-r-cases, KMT2A r+ B-ALLs showed a higher blast percentage, significantly higher mean fluorescence intensity (MFI) of CD45, CD38, and CD58, and significantly lower MFI of CD34, CD22, TdT, and CD123.The study confirmed differences in CD45, CD34, CD22, and TdT MFI within the same immunologic EGIL group (European Group for the immunological classification of leukemias), indicating no influence of the B-ALLs EGIL subtype on the KMT2A-r+ B-ALLs immunophenotype. Our data demonstrate the association between NG2 and KMT2A-r in B-ALLs identify a distinctive immunophenotypic pattern, useful for rapid identification in diagnostic routines of these subtypes of B-ALLs with a poor prognosis that benefits from a specific therapeutic approach.

Identification of a distal enhancer regulating hedgehog interacting protein gene in human lung epithelial cells

An intergenic region at chromosome 4q31 is one of the most significant regions associated with COPD susceptibility and lung function in GWAS. In this region, the implicated causal gene HHIP has a unique epithelial expression pattern in adult human lungs, in contrast to dominant expression in fibroblasts in murine lungs. However, the mechanism underlying the species-dependent cell type-specific regulation of HHIP remains largely unknown. We employed snATAC-seq analysis to identify open chromatin regions within the COPD GWAS region in various human lung cell types. ChIP-quantitative PCR, reporter assays, chromatin conformation capture assays and Hi-C assays were conducted to characterize the regulatory element in this region. CRISPR/Cas9-editing was performed in BEAS-2B cells to generate single colonies with stable knockout of the regulatory element. RT-PCR and Western blot assays were used to evaluate expression of HHIP and epithelial-mesenchymal transition (EMT)-related marker genes. We identified a distal enhancer within the COPD 4q31 GWAS locus that regulates HHIP transcription at baseline and after TGFβ treatment in a SMAD3-dependent, but Hedgehog-independent manner in human bronchial epithelial cells. The distal enhancer also maintains chromatin topological domains near 4q31 locus and HHIP gene. Reduced HHIP expression led to increased EMT induced by TGFβ in human bronchial epithelial cells. A distal enhancer regulates HHIP expression both under homeostatic condition and upon TGFβ treatment in human bronchial epithelial cells. The interaction between HHIP and TGFβ signalling possibly contributes to COPD pathogenesis. Supported by NIH grants R01HL127200, R01HL148667 and R01HL162783 (to X. Z).

Analysis of genetic variant associated with heart failure mortality implicates thymic stromal lymphopoietin as mediator of strain-induced myocardial fibroblast-mast cell crosstalk and fibrosis.

Heart failure (HF) is a leading cause of death and disability globally. Heritable factors and the extent and pattern of myocardial fibrosis are important determinants of outcomes in patients with HF. In a genome-wide association study of mortality in HF, we recently identified a genetic polymorphism on chromosome 5q22 associated with HF mortality. Here, we sought to study the mechanisms by which this variant may influence myocardial disease processes. We find that the risk allele is located in an enhancer motif upstream of the TSLP gene (encoding thymic stromal lymphopoietin), conferring increased binding of the transcription factor nescient helix-loop helix 1 (NHLH1) and increased TSLP expression in human heart. Further, we find that increased strain of primary human myocardial fibroblasts results in increased TSLP expression and that the TSLP receptor is expressed in myocardial mast cells in human single nuclei RNA sequence data. Finally, we show that TSLP overexpression induces increased transforming growth factor β expression in myocardial mast cells and tissue fibrosis. Collectively, our findings based on follow-up of a human genetic finding implicate a novel pathway in myocardial tissue homeostasis and remodeling.

Genetic Variants of CYP2C8 Gene Predisposition to Type 2 Diabetes Risk

Background: Type 2 diabetes mellitus (T2DM) is characterized by elevated blood glucose levels due to insulin resistance or inadequate insulin secretion from pancreatic beta cells. The mitochondrial CYP2C8 gene, located on chromosome 10q24, encodes cytochrome P450 and spans 37 kb with nine exons. Genetic variants in this gene may influence T2DM susceptibility. Method: This study aimed to investigate the association between genetic polymorphisms in the CYP2C8 gene (rs1934953 and rs1934952) and the risk of T2DM in Iraqi patients. Blood samples were collected from 48 participants, including 24 T2DM patients and 24 healthy controls. DNA extraction, polymerase chain reaction (PCR), and sequencing were performed to analyze genetic variations. Statistical analysis was conducted using chi-square tests, logistic regression, and Hardy-Weinberg equilibrium calculations. Results: Analysis revealed that the rs1934953 variant in the CYP2C8 gene was associated with T2DM, with the A allele showing a protective effect (odds ratio: 0.840, 95% confidence interval: 0.780-0.904, P=3.04×10-6). Additionally, an interaction effect between rs1934953 in CYP2C9 and rs12766752 in CYP2C8 on T2DM risk was observed (P=0.003). Furthermore, rs1934953 showed significant association with high-density lipoprotein cholesterol (HDL-C). At the rs1934952 C/T locus, a transition type genetic mutation was detected, with the TT genotype considered a risk factor for T2DM, while the CC and CT genotypes were protective. The Hardy-Weinberg probability value for the patient group was 0.0321, indicating notable discrepancies in genotype distribution, while the healthy group showed no significant differences (Hardy probability: 0.2001). The TT genotype at rs1934953 was associated with a decreased risk of T2DM, while the CC and CT genotypes were potential risk factors. Conversely, at rs1934952, the CC and CT genotypes were protective against T2DM, while the TT genotype was associated with increased risk. Conclusion: in conclusion, the study indicates that there may be links between CYP2C8 gene variances and an increased chance of type 2 diabetes in Iraqi patients.

The Role of Aminopeptidase ERAP1 in Human Pathology-A Review.

Aminopeptidases are a group of enzymatic proteins crucial for protein digestion, catalyzing the cleavage of amino acids at the N-terminus of peptides. Among them are ERAP1 (coding for endoplasmic reticulum aminopeptidase 1), ERAP2 (coding for endoplasmic reticulum aminopeptidase 2), and LNPEP (coding for leucyl and cystinyl aminopeptidase). These genes encoding these enzymes are contiguous and located on the same chromosome (5q21); they share structural homology and functions and are associated with immune-mediated diseases. These aminopeptidases play a key role in immune pathology by cleaving peptides to optimal sizes for binding to the major histocompatibility complex (MHC) and contribute to cellular homeostasis. By their ability to remove the extracellular region of interleukin 2 and 6 receptors (IL2, IL6) and the tumor necrosis factor receptor (TNF), ERAP1 and ERAP2 are involved in regulating the innate immune response and, finally, in blood pressure control and angiogenesis. The combination of specific genetic variations in these genes has been linked to various conditions, including autoimmune and autoinflammatory diseases and cancer, as well as hematological and dermatological disorders. This literature review aims to primarily explore the impact of ERAP1 polymorphisms on its enzymatic activity and function. Through a systematic examination of the available literature, this review seeks to provide valuable insights into the role of ERAP1 in the pathogenesis of various diseases and its potential implications for targeted therapeutic interventions. Through an exploration of the complex interplay between ERAP1 and various disease states, this review contributes to the synthesis of current biomedical research findings and their implications for personalized medicine.

Williams-Beuren syndrome in pediatric T-cell acute lymphoblastic leukemia: A rare case report and review of literature.

Williams-Beuren syndrome (WBS) is a rare genetic disorder caused by hemizygous microdeletion of contiguous genes on chromosome 7q11.23. Although the phenotype features extensive heterogeneity in severity and performance, WBS is not considered to be a predisposing factor for cancer development. Currently, hematologic cancers, mainly Burkitt lymphoma, are rarely reported in patients with WBS. Here in, we report a unique case of T-cell acute lymphoblastic leukemia in a male child with WBS. This retrospective study analyzed the clinical data of this case receiving chemotherapy were analyzed. This is a retrospective study. The patient, who exhibited a typical WBS phenotype and presented with hemorrhagic spots. Chromosomal genome-wide chip analysis (CMA) revealed abnormalities on chromosomes 7 and 9. The fusion gene STIL-TAL1 and mutations in BCL11B, NOTCH1, and USP7 have also been found and all been associated with the occurrence of T-cell leukemia. The patient responded well to the chemotherapy. To the best of our knowledge, this is the first reported case of WBS in T-cell acute lymphoblastic leukemia. We want to emphasize that the occurrence of leukemia in this patient might be related to the loss of 7q11.23 and microdeletion of 9p21.3 (including 3 TSGs), but the relationship between WBS and malignancy remains unclear. Further studies are required to clarify the relationship between WBS and malignancy.

Sleep disturbances and behavioral symptoms in pediatric Sotos syndrome.

Sotos syndrome (SoS) is a rare overgrowth genetic disease caused by intragenic mutations or microdeletions of the NSD1 gene located on chromosome 5q35. SoS population might present cognitive impairment and a spectrum of behavioral characteristics, with a worse profile in patients with microdeletion. Although patients with SoS are known to have impaired sleep habits, very little data are available. The present study aimed to assess the prevalence of sleep disorders (SDs) in a pediatric cohort of patients with SoS and their correlation with neuropsychiatric profiles. We included patients with a SoS diagnosis and age < 18 years; all patients underwent a comprehensive neuropsychological assessment, including evaluation of cognition, adaptive functions through the Adaptive Behavior Assessment System-Second Edition (ABAS-II), and behavioral problems using the Achenbach Child Behavior Checklist (CBCL) and Conners' Parent Rating Scale-Revised (CPRS-R:L) questionnaire. To investigate the presence of SD parents, the Sleep Disturbance Scale for Children (SDSC) was completed. Thirty-eight patients (M 61%, F 39%, mean age 11.1 ± 4.65 years) were included in the study. Although only two had a prior SD diagnosis, 71.1% (N = 27) exhibited pathological scores on SDSC. No statistically significant associations were found between positive SDSC results and genetic microdeletion, intellectual disability (ID), or other medical conditions/treatments. However, a positive correlation emerged between SDSC scores and Conners' Global Index (p = 0.048) and Restless/Impulsive (p = 0.01) scores, CBCL externalizing (p = 0.02), internalizing (p = 0.01), and total scores (p = 0.05). Conversely, a negative linear relationship was observed between the SDSC score and the ABAS GAC and ABAS CAD scores (p = 0.025). We detected an SD in 71.1% of our sample, with a positive relation between SD and internalizing and externalizing symptom levels, especially hyperactivity and impulsivity. Our study demonstrated a high prevalence of SD in pediatric patients with SoS, highlighting that all patients should be screened for this problem, which has a great impact on the quality of life of patients and their families.