Next-generation Sequencing Studies Research Articles

Clinical applications and challenges of metagenomic next-generation sequencing in the diagnosis of pediatric infectious disease

Abstract Infectious diseases seriously threaten the lives of children. Timely and accurate detection of pathogenic microorganisms and targeted medication are the keys to the diagnosing and treatment of infectious diseases in children. The next-generation metagenomic sequencing technology has attracted great attention in infectious diseases because of its characteristics such as no culture, high throughput, short detection cycle, wide coverage, and a good application prospect. In this paper, we review the studies of metagenomic next-generation sequencing in pediatric infectious diseases and analyze the challenges of its application in pediatric diseases.

Analysis of mutation profiles in extranodal NK/T-cell lymphoma: clinical and prognostic correlations.

The molecular pathogenesis of extranodal NK/T-cell lymphoma (NKTCL) remains obscured despite the next-generation sequencing (NGS) studies explored on ever larger cohorts in the last decade. We addressed the highly variable mutation frequencies reported among previous studies with comprehensive amplicon coverage and enhanced sequencing depth to achieve higher genomic resolution for novel genetic discovery and comparative mutational profiling of the oncogenesis of NKTCL. Targeted exome sequencing was conducted to interrogate 415 cancer-related genes in a cohort of 36 patients with NKTCL, and a total of 548 single nucleotide variants (SNVs) and 600 Copy number variances (CNVs) were identified. Recurrent amplification of the MCL1 (67%) and PIM1 (56%) genes was detected in a dominant majority of patients in our cohort. Functional mapping of genetic aberrations revealed that an enrichment of mutations in the JAK-STAT signaling pathway, including the cytokine receptor LIFR (copy number loss) upstream of JAK3, STAT3 (activating SNVs), and downstream effectors of MYC, PIM1 and MCL1 (copy number gains). RNA in situ hybridization showed the significant consistence of MCL1 RNA level and copy number of MCL1 gene. We further correlated molecular and clinical parameters with overall survival (OS) of these patients. When correlations were analyzed by univariate followed by multivariate modelling, only copy number loss of LIFR gene and stage (III-IV) were independent prognostic factors of reduced OS. Our findings identified that novel loss of LIFR gene significantly correlated with the adverse clinical outcome of NKTCL patients and provided therapeutic opportunities for this disease through manipulating LIFR.

The contribution of genetics and epigenetics to MAFLD susceptibility.

Metabolic dysfunction-associated fatty liver disease (MAFLD) is the most common liver disease worldwide. The risk of developing MAFLD varies among individuals, due to a combination of environmental inherited and acquired genetic factors. Genome-wide association and next-generation sequencing studies are leading to the discovery of the common and rare genetic determinants of MAFLD. Thanks to the great advances in genomic technologies and bioinformatics analysis, genetic and epigenetic factors involved in the disease can be used to develop genetic risk scores specific for liver-related complications, which can improve risk stratification. Genetic and epigenetic factors lead to the identification of specific sub-phenotypes of MAFLD, and predict the individual response to a pharmacological therapy. Moreover, the variant transcripts and protein themselves represent new therapeutic targets. This review will discuss the current status of research into genetic as well as epigenetic modifiers of MAFLD development and progression.

Gut Bacteria Provide Genetic and Molecular Reporter Systems to Identify Specific Diseases.

With genetic information gained from next-generation sequencing (NGS) and genome-wide association studies (GWAS), it is now possible to select for genes that encode reporter molecules that may be used to detect abnormalities such as alcohol-related liver disease (ARLD), cancer, cognitive impairment, multiple sclerosis (MS), diabesity, and ischemic stroke (IS). This, however, requires a thorough understanding of the gut-brain axis (GBA), the effect diets have on the selection of gut microbiota, conditions that influence the expression of microbial genes, and human physiology. Bacterial metabolites such as short-chain fatty acids (SCFAs) play a major role in gut homeostasis, maintain intestinal epithelial cells (IECs), and regulate the immune system, neurological, and endocrine functions. Changes in butyrate levels may serve as an early warning of colon cancer. Other cancer-reporting molecules are colibactin, a genotoxin produced by polyketide synthetase-positive Escherichia coli strains, and spermine oxidase (SMO). Increased butyrate levels are also associated with inflammation and impaired cognition. Dysbiosis may lead to increased production of oxidized low-density lipoproteins (OX-LDLs), known to restrict blood vessels and cause hypertension. Sudden changes in SCFA levels may also serve as a warning of IS. Early signs of ARLD may be detected by an increase in regenerating islet-derived 3 gamma (REG3G), which is associated with changes in the secretion of mucin-2 (Muc2). Pro-inflammatory molecules such as cytokines, interferons, and TNF may serve as early reporters of MS. Other examples of microbial enzymes and metabolites that may be used as reporters in the early detection of life-threatening diseases are reviewed.

TP53-specific mutations serve as a potential biomarker for homologous recombination deficiency in breast cancer: a clinical next-generation sequencing study.

TP53 mutations and homologous recombination deficiency (HRD) occur frequently in breast cancer. However, the characteristics of TP53 pathogenic mutations in breast cancer patients with/without HRD are not clear. Clinical next-generation sequencing (NGS) of both tumor and paired blood DNA from 119 breast cancer patients (BRCA-119 cohort) was performed with a 520-gene panel. Mutations, tumor mutation burden (TMB), and genomic HRD scores were assessed from NGS data. NGS data from 47 breast cancer patients in the HRD test cohort were analyzed for further verification. All TP53 pathogenic mutations in patients had somatic origin, which was associated with the protein expression of estrogen receptor and progestogen receptor. Compared to patients without TP53 pathologic mutations, patients with TP53 pathologic mutations had higher levels of HRD scores and different genomic alterations. The frequency of TP53 pathologic mutation was higher in the HRD-high group (HRD score≥42) relative to that in the HRD-low group (HRD score<42). TP53 has different mutational characteristics between the HRD-low and HRD-high groups. TP53-specific mutation subgroups had diverse genomic features and TMB. Notably, TP53 pathogenic mutations predicted the HRD status of breast cancer patients with an area under the curve (AUC) of 0.61. TP53-specific mutations, namely HRD-low mutation, HRD-high mutation, and HRD common mutation, predicted the HRD status of breast cancer patients with AUC values of 0.32, 0.72, and 0.58, respectively. Interestingly, TP53 HRD-high mutation and HRD common mutation combinations showed the highest AUC values (0.80) in predicting HRD status. TP53-specific mutation combinations predict the HRD status of patients, indicating that TP53 pathogenic mutations could serve as a potential biomarker for poly-ADP-ribose polymerase (PARP) inhibitors in breast cancer patients .

Abstract 6927: A refined view of pancreatic cancer genomic evolution through single-nucleus DNA sequencing

Abstract Numerous next-generation sequencing studies have provided an overview pancreatic ductal adenocarcinoma (PDAC)’s genomic evolution. But how its genome evolves through treatment and metastasis has not been extensively studied due to lack of samples and technical limitation of bulk sequencing on low-tumor purity samples. Herein we applied targeted single-nucleus DNA sequencing (snDNA-seq) to a cohort of 18 patients, each with &amp;gt;= 2 multiregional/longitudinal samples, totaling 65 samples. These included 5 early-stage resections, 11 stage IV autopsies and 2 biopsy-derived organoids taken pre- and post-treatment. We also developed a set of computational methods for this new datatype to delineate genomic evolution at high resolution. Despite higher sensitivity than bulk, snDNA-seq did not uncover significant subclonal single-nucleotide variations (SNVs) on our panel targeting 253 select genes for PDAC. But it detected a higher frequency of CDKN2A (72% against 30%) and SMAD4 (56% against 32%) alterations, mostly attributed to chromosomal deletions. Many were subclonal or only affected a few hundred base-pairs of the gene, making them elusive to bulk sequencing. Except for one case driven by BRCA2 mutations rather than the canonical KRAS oncogene, other patients had mostly linear phylogenies with more SNVs occurring before the most recent common ancestor (MRCA) of clones, for early/late-stage and longitudinal cases alike. This early fixation of drivers and rapid clonal sweep afterwards likely correlates with the particular aggressiveness of PDAC. Metastatic clones almost always fell towards the end of phylogenies and were shared among spatially separated sites, indicating late metastatic dissemination in molecular evolution time. Metastases to the liver and diaphragm appeared to be more genetically evolved than other sites, likely due to harsher selective pressure cast by the metastatic routes/distal microenvironments. 16 of 18 PDACs were observed to converge towards tumor cell-intrinsic TGF-β unresponsiveness by mutating various components of the pathway. Such convergent evolution usually happened at the primary site, indicating a strong selective advantage of the phenotype in the desmoplastic, nutrient-poor pancreas microenvironment. Continuous evolution was seen through treatment and metastasis, driven by seemingly random genome-scale copy number variations (CNVs) and focal amplification/deletions to genes such as KRAS, CDKN2A, SMAD4, MYC. These insights on PDAC’s genomic evolution inform more precision medicine efforts to come. Early fixation of driver SNVs sculpts a largely homogeneous disease that could be uniformly targeted. But special care should be taken to obviate resistance mechanisms conferred by continuously evolving CNV events- compared to SNVs, these mechanisms provide faster remodeling of the genome, and thus faster generation of new phenotypes and adaptation. Citation Format: Haochen Zhang, Palash Sashittal, Elias-Ramzey Karnoub, Akhil Jakatdar, Shigeaki Umeda, Nicolas Lecomte, Jungeui Hong, Katelyn Mullen, Akimasa Hayashi, Caitlin A. McIntyre, Benjamin J. Raphael, Christine A. Iacobuzio-Donahue. A refined view of pancreatic cancer genomic evolution through single-nucleus DNA sequencing [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 6927.

Capture-based targeted sequencing using a T-cell control in myeloid malignancies and idiopathic cytopenias.

We report on a study of next-generation sequencing in 257 patients undergoing investigations for cytopenias. We sequenced bone marrow aspirates using a target enrichment panel comprising 82 genes and used T cells from paired blood as a control. One hundred and sixty patients had idiopathic cytopenias, 81 had myeloid malignancies and 16 had lymphoid malignancies or other diagnoses. Forty-seven of the 160 patients with idiopathic cytopenias had evidence of somatic pathogenic variants consistent with clonal cytopenias. Only 39 genes of the 82 tested were mutated in the 241 patients with either idiopathic cytopenias or myeloid neoplasms. We confirm that T cells can be used as a control to distinguish between germline and somatic variants. The use of paired analysis with a T-cell control significantly reduced the time molecular scientists spent reporting compared to unpaired analysis. We identified somatic variants of uncertain significance (VUS) in a higher proportion (24%) of patients with myeloid malignancies or clonal cytopenias compared to less than 2% of patients with non-clonal cytopenias. This suggests that somatic VUS are indicators of a clonal process. Lastly, we show that blood depleted of lymphocytes can be used in place of bone marrow as a source of material for sequencing.

Whole-exome sequencing is feasible on a fresh-frozen skin sample of intravascular large B cell lymphoma

Intravascular large B-cell lymphoma (IVLBCL) is a rare aggressive extranodal non-Hodgkin lymphoma. The predominant, if not exclusive, growth of neoplastic cells within the lumina of small-sized vessels represents the hallmark of the disease. Diagnosis is challenging due to the absence of marked lymphadenopathy, the highly heterogeneous clinical presentation, and the rarity of the condition. Clinical presentation is characterized by variable combinations of nonspecific signs and symptoms (such as fever and weight loss), organ-specific focal manifestations due to altered perfusion, and hemophagocytic syndrome. The rarity of this entity and the paucity of neoplastic cells in biopsy samples hamper the study of recurrent molecular abnormalities. The purpose of this study was to explore the feasibility of a different approach to recover a sufficient amount of DNA of acceptable quality to perform next-generation sequencing studies. Here, we report the findings of whole-exome next-generation sequencing performed on a fresh-frozen cutaneous sample of IVLBCL, paired with the patient saliva used as germline DNA. To increase the cancer cell fraction, only the subcutaneous tissue was selected. With this approach, we obtained high-quality DNA and were able to identify oncogenic mutations specific for this entity and recapitulating its post-germinal center origin, even if the tumor fraction was low. Molecular studies performed on fresh-frozen cutaneous sample are feasible in IVLBCL, especially when analysis is restricted to the subcutaneous tissue. Wide adoption of this reproducible and cost-effective approach may foster further studies, which may be of help in supporting diagnosis, providing pathogenetic insights, and guiding treatment decisions.

Genetic Risk Factors and Clinical Outcomes in Childhood Eye Cancers: A Review.

Childhood eye cancers, although rare, present substantial health challenges, affecting the pediatric population with a remarkable impact on their lives and families. This comprehensive review provides insights into the various types of ocular tumors, primarily focusing on malignant eye tumors, their genetic predispositions, and advancements in managing these conditions. Understanding the genetic risk factors is crucial for early detection, risk assessment, and the development of targeted therapies. This review discusses genome-wide association (GWAS) and next-generation sequencing (NGS) studies to find common and rare genetic variants. Furthermore, it also explores the outcomes and implications of these genetic discoveries in treating pediatric ocular cancer. These findings underscore the significance of genetic research in guiding early interventions and improving outcomes in children with ocular cancers.

(045) Comparing Bacterial Presence with the Usage of 0.05% Chlorhexidine Gluconate (CHG) Lavage During Urologic Prosthesis Revision Surgery: Update on Results

Abstract Introduction An Inflatable Penile Prosthesis (IPP) is third line surgical therapy for refractory ED. An IPP uses a fluid-filled reservoir with a pump and valve system to activate inflation and deflation. Although penile implants achieve the highest success rates in ED treatment, the possible presence of bacteria on the device itself or bacteria exposure accumulated during the surgery increases the risk of progression into biofilm or infection. Biofilm complicates the bacteria eradication effort and can ultimately jeopardize the implant. Often, the only way to treat the post-op infection is with implant removal. Currently, many preventative measures, such as different perioperative irrigations, are being studied to reduce the number of penile implant infections. Research has shown that irrigation at the time of both infectious and noninfectious surgery lowers subsequent infection rates. Different solutions like saline, antibiotic, betadine, and hydrogen peroxide solutions have been considered. Recently, orthopedic literature has shown that 0.05% Chlorhexidine Gluconate (CHG) lavage has effectively reduced biofilm in artificial joint procedures. Objective The purpose of this study is to determine the effectiveness of CHG lavage on bacterial presence in IPP implant spaces. We hypothesize that CHG will lower bacterial presence after washing out implant spaces at time of replacement for infections and mechanical failure. Methods We aimed to investigate a series of patients who underwent revision IPP surgery while utilizing FDA-approved CHG lavage for irrigation and compared the bacterial presence before and after CHG washout. Additionally, Next Generation Sequencing (NGS), a DNA sequencing technology, was used to further identify the pathogens involved. Results Between 2021 to 2023, 48 patients underwent IPP revision surgery for either infectious or noninfectious reasons. During the operation, a section of the capsule tissue surrounding the implanted IPP pump was first taken and sent for cultures. NGS studies were also sent out. After the implant removal, all implant spaces were irrigated and washed out with CHG (two 450-mL bottles). A second tissue culture was then obtained post washout. Of the 48 patients, there were 4 positive bacterial cultures before washout and 13 positive NGS results. Results of the post CHG washout cultures were all negative. Conclusions It appears that irrigation with 0.05% Chlorhexidine Gluconate solution is an effective antiseptic that can decrease bacterial presence, and hopefully reduce IPP infections. Disclosure Any of the authors act as a consultant, employee or shareholder of an industry for: Microgen Dx, Irrisept.

Lactobacilli in COVID-19: A Systematic Review Based on Next-Generation Sequencing Studies.

The global pandemic was caused by the SARS-CoV-2 virus, known as COVID-19, which primarily affects the respiratory and intestinal systems and impacts the microbial communities of patients. This systematic review involved a comprehensive search across the major literature databases to explore the relationship between lactobacilli and COVID-19. Our emphasis was on investigations employing NGS technologies to explore this connection. Our analysis of nine selected studies revealed that lactobacilli have a reduced abundance in the disease and an association with disease severity. The protective mechanisms of lactobacilli in COVID-19 and other viral infections are likely to be multifaceted, involving complex interactions between the microbiota, the host immune system, and the virus itself. Moreover, upon closely examining the NGS methodologies and associated statistical analyses in each research study, we have noted concerns regarding the approach used to delineate the varying abundance of lactobacilli, which involves potential biases and the exclusion of pertinent data elements. These findings provide new insight into the relationship between COVID-19 and lactobacilli, highlighting the potential for microbiota modulation in COVID-19 treatment.

Artificial intelligence and database for NGS-based diagnosis in rare disease.

Rare diseases (RDs) are rare complex genetic diseases affecting a conservative estimate of 300 million people worldwide. Recent Next-Generation Sequencing (NGS) studies are unraveling the underlying genetic heterogeneity of this group of diseases. NGS-based methods used in RDs studies have improved the diagnosis and management of RDs. Concomitantly, a suite of bioinformatics tools has been developed to sort through big data generated by NGS to understand RDs better. However, there are concerns regarding the lack of consistency among different methods, primarily linked to factors such as the lack of uniformity in input and output formats, the absence of a standardized measure for predictive accuracy, and the regularity of updates to the annotation database. Today, artificial intelligence (AI), particularly deep learning, is widely used in a variety of biological contexts, changing the healthcare system. AI has demonstrated promising capabilities in boosting variant calling precision, refining variant prediction, and enhancing the user-friendliness of electronic health record (EHR) systems in NGS-based diagnostics. This paper reviews the state of the art of AI in NGS-based genetics, and its future directions and challenges. It also compare several rare disease databases.

Human Papillomavirus Infections and the Role Played by Cervical and Cervico-Vaginal Microbiota-Evidence from Next-Generation Sequencing Studies.

This comprehensive review encompasses studies examining changes in the cervical and cervico-vaginal microbiota (CM and CVM) in relation to human papillomavirus (HPV) using next-generation sequencing (NGS) technology. HPV infection remains a prominent global health concern, with a spectrum of manifestations, from benign lesions to life-threatening cervical cancers. The CM and CVM, a unique collection of microorganisms inhabiting the cervix/vagina, has emerged as a critical player in cervical health. Recent research has indicated that disruptions in the CM and CVM, characterized by a decrease in Lactobacillus and the overgrowth of other bacteria, might increase the risk of HPV persistence and the progression of cervical abnormalities. This alteration in the CM or CVM has been linked to a higher likelihood of HPV infection and cervical dysplasia. NGS technology has revolutionized the study of the cervical microbiome, providing insights into microbial diversity, dynamics, and taxonomic classifications. Bacterial 16S rRNA gene sequencing, has proven invaluable in characterizing the cervical microbiome, shedding light on its role in HPV infections and paving the way for more tailored strategies to combat cervical diseases. NGS-based studies offer personalized insights into an individual's cervical microbiome. This knowledge holds promise for the development of novel diagnostic tools, targeted therapies, and preventive interventions for cervix-related conditions, including cervical cancer.

Application of Next-Generation Sequencing Technology in Southeast Asia: A Practical Framework for Advancing Wildlife Conservation

Next-generation sequencing (NGS) has transformed genomics, presenting significant potential for advancing wildlife conservation. NGS technology offers opportunities and challenges for addressing scientific questions in wildlife management. Unfortunately, there is a lack of comprehensive records on NGS implementation in Southeast Asia, particularly concerning wildlife conservation. To address this gap, we analyzed NGS studies focused on wildlife monitoring in Southeast Asia and introduced a practical framework for implementing NGS technologies in global wildlife conservation, especially in Southeast Asia. We systematically reviewed NGS studies in wildlife monitoring from the SCOPUS database. We identified 137 relevant publications from 11 countries, with Malaysia contributing 36% of the studies. The included studies were categorized into five themes: species identification, dietary assessment, health monitoring, taxonomic resolution, and whole-genome sequencing, with the majority focusing on 38 publications related to wildlife health. The framework developed in this study help the researchers and conservation practitioners with insights on NGS technology application in conservation while also addressing the benefits, limitations, and ethical considerations associated with NGS use. This review offers a brief overview of NGS usage and provides guidelines for embracing NGS as a valuable tool for effective wildlife conservation strategies in our rapidly changing world.

Detection of invasive Bartonella infections with next-generation sequencing of microbial cell-free DNA.

We report 9 patients with invasive Bartonella infections, including 5 with endocarditis, who were diagnosed with microbial cell-free DNA next-generation sequencing and Bartonella serology studies. Diagnosis with plasma mcfDNA NGS enabled a faster clinical and laboratory diagnosis in 8 patients. Prompt diagnosis impacted antibiotic management in all 9 patients.

The Role of Bifidobacterium in Liver Diseases: A Systematic Review of Next-Generation Sequencing Studies.

The physiopathology of liver diseases is complex and can be caused by various factors. Bifidobacterium is a bacterial genus commonly found in the human gut microbiome and has been shown to influence the development of different stages of liver diseases significantly. This study investigated the relationship between the Bifidobacterium genus and liver injury. In this work, we performed a systematic review in major databases using the key terms "Bifidobacterium", "ALD", "NAFLD", "NASH", "cirrhosis", and "HCC" to achieve our purpose. In total, 31 articles were selected for analysis. In particular, we focused on studies that used next-generation sequencing (NGS) technologies. The studies focused on assessing Bifidobacterium levels in the diseases and interventional aimed at examining the therapeutic potential of Bifidobacterium in the mentioned conditions. Overall, the abundance of Bifidobacterium was reduced in hepatic pathologies. Low levels of Bifidobacterium were associated with harmful biochemical and physiological parameters, as well as an adverse clinical outcome. However, interventional studies using different drugs and treatments were able to increase the abundance of the genus and improve clinical outcomes. These results strongly support the hypothesis that changes in the abundance of Bifidobacterium significantly influence both the pathophysiology of hepatic diseases and the related clinical outcomes. In addition, our critical assessment of the NGS methods and related statistical analyses employed in each study highlights concerns with the methods used to define the differential abundance of Bifidobacterium, including potential biases and the omission of relevant information.

Integrative NGS testing reveals clonal dynamics of adverse genomic defects contributing to a natural progression in treatment-naïve CLL patients.

Large-scale next-generation sequencing (NGS) studies revealed extensive genetic heterogeneity, driving a highly variable clinical course of chronic lymphocytic leukaemia (CLL). The evolution of subclonal populations contributes to diverse therapy responses and disease refractoriness. Besides, the dynamics and impact of subpopulations before therapy initiation are not well understood. We examined changes in genomic defects in serial samples of 100 untreated CLL patients, spanning from indolent to aggressive disease. A comprehensive NGS panel LYNX, which provides targeted mutational analysis and genome-wide chromosomal defect assessment, was employed. We observed dynamic changes in the composition and/or proportion of genomic aberrations in most patients (62%). Clonal evolution of gene variants prevailed over the chromosomal alterations. Unsupervised clustering based on aberration dynamics revealed four groups of patients with different clinical behaviour. An adverse cluster was associated with fast progression and early therapy need, characterized by the expansion of TP53 defects, ATM mutations, and 18p- alongside dynamic SF3B1 mutations. Our results show that clonal evolution is active even without therapy pressure and that repeated genetic testing can be clinically relevant during long-term patient monitoring. Moreover, integrative NGS testing contributes to the consolidated evaluation of results and accurate assessment of individual patient prognosis.

Clonal Hematopoiesis in Patients with Immune Thrombocytopenia: Preliminary Results of a Cross-Sectional Study

Immune thrombocytopenia (ITP) is an acquired disorder marked by immune-mediated attack to platelets. However, the borders between ITP and clonal cytopenias, such as low risk myelodysplastic syndromes, may be difficult to establish. Detection of somatic mutations on peripheral blood leukocytes (PBL) through next generation sequencing (NGS) is gaining diagnostic and prognostic power in myeloid disorders and may be found also in individuals without blood malignancies, namely clonal hematopoiesis with indeterminate potential (CHIP). The prevalence and significance of CHIP in immune-mediated hematological diseases, such as ITP, is not clearly known. Here we present the preliminary results of a cross-sectional study on adult ITP patients followed at our clinics from 2019 until March 2023. History of any hematological malignancy was an exclusion criterion. An NGS study on PBL was performed by Ion Torrents5, Ion Reporters software 5.2, evaluating mutations in 69 potentially oncogenic genes present in the Oncomine Myeloid Research Assay diagnostic panel. Only mutations with a variant allele frequency (VAF) of 2% were considered, while mutations with VAF &amp;gt; 40% were regarded as potentially germline and discarded. To correlate mutational status with clinical features, a two-tailed Fisher's exact test was used for analysis of dichotomic variables, while a two-sided student's t was used for continuous ones. We included 37 ITP patients (Table 1), 14 of which (38%) had at least one mutation. After exclusion of 4 mutations with VAF &amp;gt; 40%, a total of 17 mutations were considered, affecting 11/37 (30%) patients (NGS-positive). Mutated genes were TET2 (7/17, 41%), DNMT3A (4/17, 18%), SRSF2 (2/17, 12%), and SF3B1, MPL, ASXL1 and NF1 in 1/17 (6%) case each. All patients, except two, had received at least one treatment line (steroids +/- intravenous immunoglobulins), 32 (86%) and 14 (38%) subjects 2 or 3 lines, respectively. Median age of NGS-positive was significantly higher than NGS-negative patients: 73 years, interquartile range (IQR) 68 - 76 vs 62 years, IQR 52 - 70 (p = 0.02). NGS-positive had a slightly lower rate of complete response (CR; PLT &amp;gt; 100 x 10 9/L) after steroid treatment, compared with NGS-negative patients (40% vs 60%, respectively). Among the 9 NGS-positive patients who received thrombopoietin receptor agonists (TPO-RA), only 2 were evaluated before, and the remaining after a median of 2.6 years from TPO-RA start. Considering the 9 patients treated with TPO-RA, NGS-positive had a slightly lower rate of CR than NGS-negative patients (44% vs 79%, respectively). In this respect, we did not find substantial disparities in distribution or VAF of gene mutations between patients who fully responded to TPO-RA and those failing to achieve CR. With the caveat of a cross-sectional analysis in a limited number of cases, these data show the presence of CHIP in 1/3 of multi-treated ITP patients, a frequency similar to that of a much more elderly Italian population &amp;gt;80-year-old (Rossi et al, Blood. 2021), suggesting a possible role of autoimmunity/inflammation and treatment in clonal selection.

ZMYM3 Mutations Cooperate with NOTCH1 Alterations, Reduce Histone H4 Acetylation and Promote Apoptosis Evasion in Chronic Lymphocytic Leukemia

Introduction: Recent next-generation sequencing (NGS) studies have identified up to 200 recurrently mutated genes in chronic lymphocytic leukemia (CLL), the vast majority of which appear mutated in &amp;lt;5% of CLL cases. Among the long list of CLL candidate driver genes is ZMYM3, a gene mutated in 2-4% of CLL patients. Since the impact of ZMYM3 mutations is unknown, we aimed to identify their clinical and biological consequences in CLL. Methods: 487 CLL patients were analyzed by targeted NGS using a customized panel of 54 CLL-related genes to characterize the mutational profile of ZMYM3 mutated patients ( ZMYM3 MUT) and the clinical impact of these variants. In addition, we introduced ZMYM3 truncating mutations into the CLL-derived HG3 cell line with two genetic backgrounds: wild-type (WT), and NOTCH1 mutated cells ( NOTCH1 MUT), to generate cells with either single ZMYM3 MUT, NOTCH1 MUT or combined ZMYM3 MUT NOTCH1 MUT. In these CLL models, we evaluated the impact of these alterations in gene expression, apoptosis, growth and DNA damage response (DDR). Results: A total of 32 ZMYM3 variants were identified in 30 CLL patients, most of which were loss-of-function mutations (24/32; 75%). These variants were distributed throughout the protein sequence, with a particular recurrent frameshift mutation occurring in 6 patients (p.P48fs) that was subsequently reproduced in our CLL model. Attending to their mutational profile, we identified that 70% (21/30) of ZMYM3 MUT patients harbored mutations in the NOTCH pathway, either in NOTCH1 (60%) or in negative regulators such as MED12, FBXW7 and SPEN, suggesting a cooperation between ZMYM3 dysfunction and NOTCH1 signaling mutations in CLL evolution. Interestingly, ZMYM3 MUT patients exhibited significantly shorter time to first treatment (TFT) than ZMYM3 WT cases (median: 35 vs 52 months; p=0.010). Furthermore, ZMYM3 mutations shortened TFT of early stage CLL patients, including Binet A (48 vs 108 months, p=0.002) or Rai 0/1 (48 vs 91 months, p=0.016), as well as in low-risk cytogenetics del(13q) patients (median: 45 vs 93 months; p=0.033). We next addressed the biological implications of ZMYM3 mutations and their co-occurrence with NOTCH1 mutations in HG3 cells. First, we performed RNA-sequencing and analyzed the number of differentially expressed genes (DEGs) (|fold change|&amp;gt;2, adjusted p-value&amp;lt;0.05). Comparing with WT cells, we detected 155 DEGs in ZMYM3 MUT and 83 DEGs in NOTCH1 MUT, whereas ZMYM3 MUT NOTCH1 MUT cells showed 690 DEGs,indicating that the combination of both mutations profoundly dysregulate gene expression. Immune regulation, apoptosis and DNA damage response were some of the biological processes dysregulated by ZMYM3 mutations (p&amp;lt;0.05). Furthermore, considering the suggested role of ZMYM3 in chromatin remodeling (Puente et al, Nature. 2015) and that ZMYM3 MUT cells showed altered expression of histone acetylation related genes (p&amp;lt;0.05), we identified that ZMYM3 mutations reduced global acetylation levels of histone H4 (p&amp;lt;0.05), which may underlie the ZMYM3-related changes in gene expression. To further define the functional effects of ZMYM3 mutations, we assessed in vitro their impact in the main dysregulated pathways identified by RNA-seq. First, we identified that ZMYM3 mutations impair DNA damage response, as reflected by the difficulties to arrest cell cycle in G2/M phase after irradiation. Moreover, we detected more γH2AX foci (p&amp;lt;0.05) in ZMYM3 MUTcells, indicating persistent DNA damage; and fewer RAD51 and BRCA1 foci than WT cells (p&amp;lt;0.001) after irradiation, suggesting defective DNA damage response. In parallel, we identified that ZMYM3 mutations promote apoptosis evasion, especially in the context of NOTCH1 mutations (p&amp;lt;0.001), which led to enhanced growth of ZMYM3 MUT NOTCH1 MUT cells (p&amp;lt;0.05). Of note, ZMYM3 MUT cells showed down-expression of caspases (-8, -7 and -3) and slightly higher levels of anti-apoptotic proteins (BCL2, MCL1 and BCL-XL), which may explain this apoptosis resistance. Conclusions: Mutations in ZMYM3 are mainly loss-of-function, associate with NOTCH1 signaling mutations and shorten TFT in CLL patients, suggesting that ZMYM3 mutational status may be a useful marker in the management of early stage CLL patients. Moreover, ZMYM3 mutations reduce histone H4 acetylation and cooperate with NOTCH1 mutations to dysregulate gene-expression, leading to impair DNA damage response and apoptosis evasion.

IPSS-M for Transplant Decision Making of Patients with Myelodysplastic Syndromes: A Retrospective Single-Center Study

Background. The only curative treatment of Myelodysplastic syndromes (MDS) is represented by allogeneic hematopoietic cell transplantation (HCT). The risk scoring system conventionally used in clinical practice for transplant decision-making is IPSS-R (Greenberg PL et al, 2012), which has been shown to predict the HCT outcome(Della Porta MG et al, 2014). The recent broader application of next generation sequencing (NGS) in clinical practice provides an abundance of molecular data and poses the challenge of better prognostic stratification in MDS patients. Recently, Bernard et al(Elsa Bernard et al, 2022) developed a molecular prognostic score called IPSS-Molecular (IPSS-M) which defines six risk categories based on the patient's molecular profile combined with clinical and cytogenetic data. In the original study, only 9% of patients underwent HSCT, therefore the utility of this score in the transplant decision making needs to be explored. Aim.The aim of this study is to evaluate the impact of IPSS-M on the outcome of HCT in patients with MDS. Methods and Results. This is a single center study including 60 consecutive MDS patients who received allogeneic HCT from 2004 to 2023 at Papa Giovanni XXIII Hospital, Bergamo. The median age at transplantation was 57 years and 70% were males. HCT related parameters are listed in Table 1. Of note, 53 out of 60 patients (88%) received an upfront HCT. According to IPSS-RA (age-adjusted IPSS-R), patients clustered in Very Low (4/60), Low (11/60), Intermediate (24/60), High (16/60) and Very High (5/60) risk groups. We retrospectively performed a NGS study before HCT by using a panel of 30 genes for all patients who had available DNA and calculated IPSS-M score for each patient. According to IPSS-M, patients clustered in Very Low (2/60), Low (12/60), Moderate Low (15/60), Moderate High (9/60), High (12/60) and Very High (10/60). Re-stratification occurred in 59% of patients (35/60), of which 22% (13/60) were down-staged and 37% (22/60) were upstaged. With a median follow-up time of 7 years after HSCT, the 5-year overall (OS) and relapse-free survival (RFS) was 67% and 64% respectively. In order to evaluate the utility of IPSS-M in estimating OS and RFS in HCT setting compared to IPSS-R, a concordance test was performed. In terms of OS and RFS, IPSS-M resulted respectively in a C-index of 0.772 and 0.729 compared to 0.567 and 0.607 of IPSS-R (table 2). Conclusions. Despite the limitations due to the small sample and the retrospective design of the study, we conclude that IPSS-M performed better compared to the conventional score in predicting RFS and OS of our MDS patients undergoing HSCT, providing data supporting the integration of clinical and molecular information in this setting. Further improvements may be achieved by integrating the molecular data with clinical information regarding HSCT-related parameters such as performance status, donor and conditioning regimen.