NGS Techniques Research Articles

CTNI-27. SYSTEMIC DELIVERY OF LOW ENERGY RADIOFREQUENCY ELECTROMAGNETIC FIELDS FOR THE TREATMENT OF PATIENTS WITH PRIMARY BRAIN TUMORS

Abstract BACKGROUND Tumor Treating Fields plus maintenance temozolomide (mTMZ) showed a survival advantage in the first-line glioblastoma (GBM) treatment. The survival benefit remains limited in patients with unmethylated MGMT gene promoter. The AutEMsys device emits low-energy amplitude modulated systemic electromagnetic fields (EMF) at patient specific frequencies. It is an outpatient procedure that can be integrated with mTMZ. METHODS This study involved a prospective compassionate access program targeting adult GBM patients using an intrabuccal EMF exposure via AutEMsys in addition to chemoRT+mTMZ. The program explored the effects on survival and patients’ reported quality-of-life (QOL) by EORTC-QL-C30. Patients underwent a 90-minute session of EMF exposure therapy repeated every 2 weeks until progression, deterioration in QOL or death. All patients had pathological specimens for diagnosis, IDH mutation status through NGS techniques, and MGMT promoter region methylation status. RESULTS 31 participants were enrolled, including 29 with GBM and 2 with diffuse midline glioma. 14 patients (45%) received EMF+chemoRT followed by EMF+mTMZ and 17 patients (55%) received EMF+mTMZ (post chemoRT). Survival time was measured from the start of mTMZ to the date of the last follow-up. The median overall survival (mOS) for all 31 patients was 26.0 months (95% CI: 14.4 – 37.2 months). Specifically for 21 patients with unmethylated MGMT, the mOS was 25.0 months (95% CI: 15.9 – 34.1 months). Similarly, for the 28 patients with IDH wildtype status, the mOS remained 26.0 months (95% CI: 9.6 – 42.4 months). The addition of AutEMsys with chemoRT+mTMZ demonstrated an improved role functioning in 79% of patients with 25% of these with >10-point score. CONCLUSION The AutEMsys device has shown promising initial results when added to chemoRT+mTMZ treatment of GBM. These findings warrant further prospective investigation and validation in a multicenter clinical trial setting.

An overview of Synlab SDN Biobank’s quality control system

Biobanks are valuable service units that ensure the usage of high-quality biological samples. They contribute to translational research, and their support may improve future therapeutic approaches. They store biological samples that can be used to examine circulation biomarkers, immune cells, and immunohistochemistry aspects of illnesses and further in-depth examinations using NGS techniques. The IRCCS Synlab SDN Biobank has about 70,000 well-preserved cryopreserved human samples from various diseases, primarily oncological but also neurological and cardiovascular. These biospecimens were taken from 25,000 participants underwent imaging with a contrast agent. The goal is to propose quality control assays that meet the requirements of the international standard ISO 9001:2015 and ISO 20387:2020 accreditation. PBMCs viability was determined, and immune subset cells were analyzed by flow cytometry. Furthermore, the expression of ubiquitous miRNAs was used to assess plasma sample integrity. The quality controls demonstrated that the biological samples were correctly cryopreserved; the preservation of human biological samples did not affect the quality of the biological samples tested. Indeed, the cryopreserved PBMCs had a vitality of more than 80%, and the lymphocyte subsets could be selected for future immune cell investigations. Furthermore, miRNA expression was highest in thawed plasma samples compared to the positive and negative controls. We evaluated the quality of our randomly selected biobank-thawed human samples. Both PBMCs and plasma samples fulfill the high-quality standards needed for biomedical research, assuring their long-term preservation. However, further research is needed in the biobanking field to establish globally accepted procedures to confirm the quality of biological samples.

From Sea to Science: Coral Aquaculture for Sustainable Anticancer Drug Development.

Marine natural products offer immense potential for drug development, but the limited supply of marine organisms poses a significant challenge. Establishing aquaculture presents a sustainable solution for this challenge by facilitating the mass production of active ingredients while reducing our reliance on wild populations and harm to local environments. To fully utilize aquaculture as a source of biologically active products, a cell-free system was established to target molecular components with protein-modulating activity, including topoisomerase II, HDAC, and tubulin polymerization, using extracts from aquaculture corals. Subsequent in vitro studies were performed, including MTT assays, flow cytometry, confocal microscopy, and Western blotting, along with in vivo xenograft models, to verify the efficacy of the active extracts and further elucidate their cytotoxic mechanisms. Regulatory proteins were clarified using NGS and gene modification techniques. Molecular docking and SwissADME assays were performed to evaluate the drug-likeness and pharmacokinetic and medicinal chemistry-related properties of the small molecules. The extract from Lobophytum crassum (LCE) demonstrated potent broad-spectrum activity, exhibiting significant inhibition of tubulin polymerization, and showed low IC50 values against prostate cancer cells. Flow cytometry and Western blotting assays revealed that LCE induced apoptosis, as evidenced by the increased expression of apoptotic protein-cleaved caspase-3 and the populations of early and late apoptotic cells. In the xenograft tumor experiments, LCE significantly suppressed tumor growth and reduced the tumor volume (PC3: 43.9%; Du145: 49.2%) and weight (PC3: 48.8%; Du145: 7.8%). Additionally, LCE inhibited prostate cancer cell migration, and invasion upregulated the epithelial marker E-cadherin and suppressed EMT-related proteins. Furthermore, LCE effectively attenuated TGF-β-induced EMT in PC3 and Du145 cells. Bioactivity-guided fractionation and SwissADME validation confirmed that LCE's main component, 13-acetoxysarcocrassolide (13-AC), holds greater potential for the development of anticancer drugs.

P-509 Unveiling reproductive risks: a retrospective analysis of carrier screening in 873 non-consanguineous couples

Abstract Study question What is the prevalence of at-risk couples for recessive genetic diseases, and can preconception carrier testing effectively identify these potential couples at risk? Summary answer High-risk couples, comprising mostly carriers of the ABCA4 and HBB genes, accounted for 3.7% of the analyzed cases, while another 3.2% categorized as moderate risk. What is known already It is widely recognized that approximately 2-3% of couples may be at risk of having an affected child with a genetic recessive disease. Expanded carrier screening tests (ECS) are currently employed to identify carrier status in healthy individuals for various severe recessive and X-linked diseases that manifest early in life, and often lack treatment options. ECS facilitates the detection of couples sharing mutated genes, allowing for risk calculation and further interventions to avoid affected pregnancies. Study design, size, duration In this retrospective descriptive study, we evaluated couples in which both partners elected to complete ECS before undergoing medically assisted reproduction across our Spanish and Italian clinics between August 2018 and January 2024. A total of 873 non-consanguineous couples were identified during the study period. Participants/materials, setting, methods All couples received pre-test genetic counseling alongside the informed consent for ECS. Saliva or blood samples were sent to an external genetics lab for the analysis of 309 genes (recessive and X linked), using NGS and complementary molecular techniques to detect pathogenic and likely pathogenic variants. Each couple’s risk was subsequently calculated. Post-test genetic counselling was offered to all of couples. Main results and the role of chance A total of 55 couples were identified as having reproductive risk, carrying pathogenic or likely pathogenic variants in genes exhibiting recessive or recessive digenic inheritance. These couples were categorized into high and moderate-risk groups based on the severity, actionability, and probability of causing classical gene-linked diseases. Ultimately, 3.5% (n = 31/873) of couples were deemed high-risk, with ABCA4 and HBB being the most frequently mutated genes, observed in 6 and 5 couples respectively (0.7% and 0.6%). Additionally, 24 couples (2.74%) were classified as moderate risk, primarily carrying a classical pathogenic variant and a non-classical pathogenic variant in the CFTR gene. This allele combination could result in a child presenting a mild cystic fibrosis phenotype, predominantly observed in males, and characterized by the absence of a vas deferens. Limitations, reasons for caution The main limitation of the study rests in interpreting the variants in healthy patients. The study does not delve into exploring the genetic heterogeneity within the identified risk groups, which may influence the severity and manifestation of diseases. Wider implications of the findings The cumulative risk observed in close to 6% of the cohort underscores the critical importance of carrier testing in guiding preconception interventions and the role and importance of having a well-trained, multidisciplinary genetics team to support these couples in reproductive decision-making with minimal anxiety and maximum knowledge. Trial registration number Not Applicable

A Review of Next-Generation Sequencing Technologies and Their Impact on Clinical Research: Assessing Clinical Efficacy and Cost-Effectiveness

In contrast to microarray methods, sequence-based technologies directly determine the nucleic acid sequence. A number of modern sequencing technologies are referred to collectively as "next-generation sequencing" (NGS), often known as "high-throughput sequencing." Compared to conventional Sanger sequencing, NGS gives orders of magnitude more data at a much lower ongoing cost. These new technologies allow for much faster and more affordable sequencing of DNA and RNA, revolutionizing the study of genomics and molecular biology. Technical improvements in NGS sequencing methods have rapidly increased sequencing volume to several billion nucleotides within a short period and at a reasonable cost. Currently, NGS is developing into a molecular microscope that is permeating almost all areas of biological research. The last ten years have seen the development of NGS platforms and methodologies, and the quality of the sequences has increased to the point where NGS is now utilized in human clinical diagnosis. Due to significant cost reductions and greater community acceptance of NGS, the utilization of NGS techniques in studying clinical trials has significantly increased. NGS is a useful tool for detecting mutations in people with cancer and genetic abnormalities. To ascertain whether NGS can cost-effectively improve patient outcomes, more thorough cost-effectiveness studies of NGS applied to patient care management are required.

Rethinking Aspergillosis in the Era of Microbiota and Mycobiota.

Aspergillosis encompasses a wide range of clinical conditions based on the interaction between Aspergillus and the host. It ranges from colonization to invasive aspergillosis. The human lung provides an entry door for Aspergillus. Aspergillus has virulence characteristics such as conidia, rapid growth at body temperature, and the production of specific proteins, carbohydrates, and secondary metabolites that allow A. fumigatus to infiltrate the lung's alveoli and cause invasive aspergillosis. Alveolar epithelial cells play an important role in both fungus clearance and immune cell recruitment via cytokine release. Although the innate immune system quickly clears conidia in immunocompetent hosts, A. fumigatus has evolved multiple virulence factors in order to escape immune response such as ROS detoxifying enzymes, the rodlet layer, DHN-melanin and toxins. Bacterial co-infections or interactions can alter the immune response, impact Aspergillus growth and virulence, enhance biofilm formation, confound diagnosis, and reduce treatment efficacy. The gut microbiome's makeup influences pulmonary immune responses generated by A. fumigatus infection and vice versa. The real-time PCR for Aspergillus DNA detection might be a particularly useful tool to diagnose pulmonary aspergillosis. Metagenomics analyses allow quick and easy detection and identification of a great variety of fungi in different clinical samples, although optimization is still required particularly for the use of NGS techniques. This review will analyze the current state of aspergillosis in light of recent discoveries in the microbiota and mycobiota.

Peritoneal Tumour DNA in Peritoneal Fluid: Emerging Tool for Peritoneal Metastasis Detection.

The prognostic significance of positive peritoneal cytology still varied between cancer types and geographical origin. However, because of the lack of sensitivity of this biomarker, conventional cytology is not routinely performed in every country. Here, we wanted to test a new biomarker, peritoneal tumour DNA, using NGS technique, in order to compare it with the historical one, in patients having peritoneal metastases of gastrointestinal or ovarian cancer.

Enhancing seafood traceability: tracking the origin of seabass and seabream from the tuscan coast area by the analysis of the gill bacterial communities

BackgroundThe seafood consumption and trade have increased over the years, and along its expected expansion pose major challenges to the seafood industry and government institutions. In particular, the global trade in fish products and the consequent consumption are linked to reliable authentication, necessary to guarantee lawful trade and healthy consumption. Alterations or errors in this process can lead to commercial fraud and/or health threats. Consequently, the development of new investigative tools became crucial in ensuring unwanted scenarios. Here we used NGS techniques through targeted metagenomics approach on the V3-V4 region of the 16S rRNA genes to characterize the gill bacterial communities in wild-caught seabream (Sparus aurata) and seabass (Dicentrarchus labrax) within different fisheries areas of the “Costa degli Etruschi’’ area in the Tuscan coast. Our challenge involved the possibility of discriminating between the microbiota of both fish species collected from three different fishing sites very close to each other (all within 100 km) in important areas from a commercial and tourist point of view.ResultsOur results showed a significant difference in the assembly of gill bacterial communities in terms of diversity (alpha and beta diversity) of both seabass and seabream in accordance with the three fishing areas. These differences were represented by a unique site -related bacterial signature, more evident in seabream compared to the seabass. Accordingly, the core membership of seabream specimens within the three different sites was minimal compared to the seabass which showed a greater number of sequence variants shared among the different fishing sites. Therefore, the LRT analysis highlighted the possibility of obtaining specific fish bacterial signatures associated with each site; it is noteworthy that specific taxa showed a unique association with the fishing site regardless of the fish species. This study demonstrates the effectiveness of target-metagenomic sequencing of gills in discriminating bacterial signatures of specimens collected from fishing areas located at a limited distance to each other.ConclusionsThis study provides new information relating the structure of the gill microbiota of seabass and seabream in a fishing area with a crucial commercial and tourist interest, namely “Costa degli Etruschi”. This study demonstrated that microbiome-based approaches can represent an important tool for validating the seafood origins with a central applicative perspective in the seafood traceability system.

Downregulation of Ribosomal Protein Genes Is Revealed in a Model of Rat Hippocampal Neuronal Culture Activation with GABA(A)R/GlyRa2 Antagonist Picrotoxin.

Long-read transcriptome sequencing provides us with a convenient tool for the thorough study of biological processes such as neuronal plasticity. Here, we aimed to perform transcriptional profiling of rat hippocampal primary neuron cultures after stimulation with picrotoxin (PTX) to further understand molecular mechanisms of neuronal activation. To overcome the limitations of short-read RNA-Seq approaches, we performed an Oxford Nanopore Technologies MinION-based long-read sequencing and transcriptome assembly of rat primary hippocampal culture mRNA at three time points after the PTX activation. We used a specific approach to exclude uncapped mRNAs during sample preparation. Overall, we found 23,652 novel transcripts in comparison to reference annotations, out of which ~6000 were entirely novel and mostly transposon-derived loci. Analysis of differentially expressed genes (DEG) showed that 3046 genes were differentially expressed, of which 2037 were upregulated and 1009 were downregulated at 30 min after the PTX application, with only 446 and 13 genes differentially expressed at 1 h and 5 h time points, respectively. Most notably, multiple genes encoding ribosomal proteins, with a high basal expression level, were downregulated after 30 min incubation with PTX; we suggest that this indicates redistribution of transcriptional resources towards activity-induced genes. Novel loci and isoforms observed in this study may help us further understand the functional mRNA repertoire in neuronal plasticity processes. Together with other NGS techniques, differential gene expression analysis of sequencing data obtained using MinION platform might provide a simple method to optimize further study of neuronal plasticity.

Laboratories Can Reliably Detect Clinically Relevant Variants in the TP53 Gene below 10 % Allelic Frequency: A Multicenter Study of ERIC, the European Research Initiative on CLL

The presence of mutations in the TP53 gene is a powerful prognostic and predictive marker in chronic lymphocytic leukemia (CLL). Widespread use of NGS has enabled the detection of variants ≤10 % variant allelic frequency (low-VAF variants); however, the overall reliability and reproducibility of NGS techniques to identify such variants have been questioned repeatedly. Individual studies using sensitive, custom NGS-based assays have mostly demonstrated the shortened overall survival (OS) and event-free survival in patients with low-VAF TP53 variants treated with chemoimmunotherapy (CIT) regimens with median survival ranging between that of TP53 variants >10 % VAF (high-VAF) and wild-type TP53 (wt- TP53). Within an ERIC multicenter study, we tested the ability of NGS methods used in diagnostic and research laboratories to detect low-VAF TP53 variants and analyzed the impact of the identified low-VAF variants on patients' survival. In the first phase of the study (Fig. 1), seven sample mixes containing 23 pathogenic TP53 variants (range, 0.7-6.3% VAF) were analyzed in 41 ERIC centers using 44 NGS-based assays. All variants were validated with droplet digital PCR (ddPCR); obtained values were used as a reference for the assessment of each NGS method's performance. NGS results were categorized as true positive (TP), false positive (FP; not present in original samples and reported by one center each), and not reported/false negative (FN). In total, laboratories reported 77.8% of all variants (784 out of 1008), reaching a sensitivity [TP/ (TP + FN)] of 85.6%, 94.5%, and 94.8% at 1%, 2%, and 3% VAF cut-off, respectively. While the VAFs of individual variants reported by laboratories varied, median values strongly correlated with ddPCR (R 2=0.9841). Thirty-eight FP variants were reported by 10 laboratories, mainly <2% VAF (23 FP of VAF ≤1%, 14 FP of VAF >1 and ≤2%, 1 FP > 2%). Individual feedback was provided to improve the methods' performance and to help set an appropriate detection limit. In the second phase of the study, 12 centers provided results of TP53 NGS-based analysis of 1092 CLL clinical samples taken before first-line treatment (median time from sample to treatment 40 days). The impact of low-VAF variants (1-10% VAF; N=59) on time to second treatment (TTST; event: second treatment, death) and OS calculated from 1 st treatment initiation was compared to that of high-VAF variants (N=123) and wt- TP53 using logrank test with Benjamini-Hochberg correction of p-values. TTST (Fig. 2) of the low-VAF group was significantly shorter compared to wt- TP53 (P=0.013; median TTST wt- TP53 3.6 y, low-VAF 2.8 y, high-VAF 1 y) in patients not treated with targeted agents (N=999). If del(17p) status was considered, median TTST was the shortest in patients with a combination of del(17p) and either high (0.8 y) or low-VAF (1 y) TP53 mutations, followed by high-VAF (1.5 y) and low-VAF (2.8 y) mutations in the absence of del(17p) (P<0.001, P=0.032, P<0.001, P=0.026, respectively, compared to wt- TP53/no del(17p) (3.6 y)). In patients receiving frontline targeted agents (N=73; enriched for TP53 mutations), the results suggested shorter TTST for the high-VAF group only, but the difference was not significant (Fig. 2; P=0.06; median wt- TP53 n.r., low-VAF 4.8 y and high-VAF 3.6 y). OS of patients with low-VAF variants was significantly shorter compared to the wt- TP53 group in patients never treated with targeted treatment (P=0.033; median OS wt- TP53 6.6 y, low-VAF 3.2 y and high-VAF 2.1 y). Targeted therapy in 2 nd or later therapy lines diminished the difference and only OS of the high-VAF group differed significantly from wt- TP53 (P<0.001; median OS wt- TP53 10.6 y, low-VAF 8.6 y, and high-VAF 5.1 y). Altogether, we show that the cumulative reliability (no FN and FP) of methods tested increased continuously with VAF (Fig. 1), reaching 30% and 64% for variants ≥1.1% and 2% VAF, respectively. The reliability was affected by the type of NGS method and bioinformatic pipeline settings. We conclude that no strict threshold can be suggested from a technical standpoint. However, our results emphasize a strong need to validate/verify the NGS method, describe its limits, and report only reliable results. From a clinical standpoint, while low-VAF variants impact clinical outcomes for patients receiving CIT in the frontline setting, their clinical impact for patients treated with novel therapies remains to be evaluated in larger cohorts.

Comparasion of Microbiome Composition in Acne Vulgaris Using Metagenomic Shotgun and 16s Rrna

<p><em>Acne vulgaris is a common skin disease in adolescents and young adults. One factor that plays a role in the development of acne vulgaris is changes in the composition of the microbiome in the skin. The microbiome is the community of microorganisms that live on the surface of the skin and plays an important role in maintaining the ecological balance of the skin. Research on microbiome composition in acne vulgaris has been conducted using various analytical methods, including shotgun metagenomics and 16S rRNA. The aim of this study was to compare the microbiome composition in acne vulgaris using shotgun metagenomics and 16S rRNA. This research method is a literature review while data collection techniques are carried out by library studies obtained from 3 databases Pubmed, Google Scholar and Science Direct. The collected data were then analyzed using qualitative analysis. The results showed that some of the most common bacteria in acne vulgaris, such as Propionibacterium acnes, Staphylococcus epidermidis, and Staphylococcus aureus. In recent years, microbiota screening has been developed using NGS techniques using metagenomic whole genome shotgun and 16S rRNA DNA sequencing analysis. NGS techniques have been able to determine the microbiota of facial skin, and differentiate the bacterial abundance of acne-prone and healthy skin.</em></p><p><strong><em><span lang="IN">Keywords : <a name="_Hlk132279597"></a>16s rRNA, Acnes Vulgaris, Microbiome, NGS</span></em></strong></p>

Microbiota present in combined endodontic-periodontal diseases and its risks for endocarditis.

Infective endocarditis (IE) is an inflammatory disease usually caused by bacteria that enter the bloodstream and establish infections in the inner linings or valves of the heart, including blood vessels. Despite the availability of modern antimicrobial and surgical treatments, IE continues to cause substantial morbidity and mortality. Oral microbiota is considered one of the most significant risk factors for IE. The objective of this study was to evaluate the microbiota present in root canal (RC) and periodontal pocket (PP) clinical samples in cases with combined endo-periodontal lesions (EPL) to detect species related to IE using NGS. Microbial samples were collected from 15 RCs and their associated PPs, also from 05 RCs with vital pulp tissues (negative control, NC). Genomic studies associated with bioinformatics, combined with structuring of a database (genetic sequences of bacteria reported for infective endocarditis), allowed for the assessment of the microbial community at both sites. Functional prediction was conducted using PICRUSt2. Parvimonas, Streptococcus, and Enterococcus were the major genera detected in the RCs and PPs. A total of 79, 96, and 11 species were identified in the RCs, PPs, and NCs, respectively. From them, a total of 34 species from RCs, 53 from PPs, and 2 from NCs were related to IE. Functional inference demonstrated that CR and PP microbiological profiles may not be the only risk factors for IE but may also be associated with systemic diseases, including myocarditis, human cytomegalovirus infection, bacterial invasion of epithelial cells, Huntington's disease, amyotrophic lateral sclerosis, and hypertrophic cardiomyopathy. Additionally, it was possible to predict antimicrobial resistance variants for broad-spectrum drugs, including ampicillin, tetracycline, and macrolides. Microorganisms present in the combined EPL may not be the only risk factor for IE but also for systemic diseases. Antimicrobial resistance variants for broad-spectrum drugs were inferred based on PICRUSt-2. State-of-the-art sequencing combined with bioinformatics has proven to be a powerful tool for conducting studies on microbial communities and could considerably assist in the diagnosis of serious infections. Few studies have investigated the microbiota in teeth compromised by combined endo-periodontal lesions (EPL), but none have correlated the microbiological findings to any systemic condition, particularly IE, using NGS techniques. In such cases, the presence of apical periodontitis and periodontal disease can increase IE risk in susceptible patients.

Abstract 1700: Clonal emergence of resistance to methotrexate in osteosarcoma barcoded PDX cells

Abstract Introduction: Osteosarcoma is known to have significant intratumoral heterogeneity with branched cancer evolution. We have studied the clonal emergence of resistance to targeted and cytotoxic chemotherapy in osteosarcoma barcoded cell lines derived from patient derived xenograft (PDX) models, in order to verify if short macroevolutionary jumps occur, as a consequence of chromosomal instability, leading to subclonal diversification after chemotherapy treatment. Methods: We have previously shown in our barcoded PDX models that, by applying selective pressure with methotrexate (MTX) IC95 treatment, a clonal subpopulations more resistant to MTX emerges. Preliminary data from Next-Gen sequencing of the genomic DNA extracted from the vehicles and selected clones have shown a wide variability of barcode abundance in the clones and the vehicles. Interestingly a reduced barcode abundance was observed in the clonal subpopulations as compared to the vehicles. Also, a wide range of clonal diversity was observed among the different clones and the vehicles, being high in the M17 PDX and its clones, and low in the OS252 PDX and its derived clones. Functional assays of MTX transport were performed by measuring the cellular uptake of [3H] MTX as previously described (Matherly L. Cancer Res. 1991) in both PDXs and derived clones. Our observations show that [3H] MTX uptake was affected differently in PDXs and derived clones, highlighting a wide variability in MTX transport, possibly due to different mutations in the reduced folate carrier (RFC) gene in different clones. In some of these clones, resistance to MTX might also be due to alterations in other genes involved in MTX cytotoxic activity (DHFR, FPGS, GGH). Results: By applying selective pressure with MTX to PDX derived cell lines we obtained clones whose genomic DNA has been studied with NGS technique. The results obtained by performing the functional assay of MTX transport on both PDXs and derived clones showed a wide variability in the MTX uptake, further supporting the initial hypothesis. Sequencing will allow us to study if there are mutations in the RFC gene and/or in other genes involved in MTX resistance in all the PDXs and derived clones. RNA sequencing (RNA-Seq) will suggest the pathway alterations that may be associated with the emergence of resistance. Conclusion - Barcoded PDX derived osteosarcoma cell lines have been created with resistant clones obtained after MTX treatment. Sequencing of the RFC gene and other genes involved in resistance to MTX, and RNA-Seq profiling will yield critical information on the clonality and mechanisms of resistance which will be presented. Acknowledgments: This work was funded by Swim Across America, the Foster Foundation, and the Barbara Epstein Foundation. Citation Format: Giuseppe Longo, Sylvester Jusu, Zhongting Zhang, Zhaohui Xu, Wendong Zhang, Michael Roth, Rui Yang, Douglas Harrison, Massimo Libra, Amer Najjar, Jonathan Gill, Richard Gorlick. Clonal emergence of resistance to methotrexate in osteosarcoma barcoded PDX cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1700.

Genetic Diversity Analysis of Banana Cultivars (Musa sp.) in Saudi Arabia Based on AFLP Marker.

Banana plantation has been introduced recently to a temperate zone in the southeastern parts of Saudi Arabia (Fifa, Dhamadh, and Beesh, located in Jazan province). The introduced banana cultivars were of a clear origin without a recorded genetic background. In the current study, the genetic variability and structure of five common banana cultivars (i.e., Red, America, Indian, French, and Baladi) were analyzed using the fluorescently labeled AFLP technique. Nine different primer pairs combinations yielded 1468 loci with 88.96% polymorphism. Among all locations, high expected heterozygosity under the Hardy-Weinberg assumption was found (0.249 ± 0.003), where Dhamadh was the highest, followed by Fifa and Beesh, respectively. Based on the PCoA and Structure analysis, the samples were not clustered by location but in pairs in accordance with the cultivar's names. However, the Red banana cultivar was found to be a hybrid between the American and Indian cultivars. Based on ΦST, 162 molecular markers (i.e., loci under selection) were detected among cultivars. Identifying those loci using NGS techniques can reveal the genetic bases and molecular mechanisms involved in the domestication and selection indicators among banana cultivars.

Study of mRNA of WT1, BAALC, EVI1, PRAME and HMGA2 genes in whole blood samples.

Simultaneous quantitative measurement of mRNA of the WT1, BAALC, EVI1, PRAME and HMGA2 genes in whole blood samples reflects the specific pathological proliferative activity in acute leukemia and their ratio is promising as a diagnostic marker. The transcriptome profile of acute leukemia cells is usually assessed using NGS or microarray techniques after a preliminary procedure for isolation of mononuclear cells. However, the results of using the multiplex PCR reaction for the simultaneous determination of all above mRNAs in whole blood samples have not been published so far. Determination of mRNA of WT1, BAALC, EVI1, PRAME and HMGA2 genes in venous blood level samples by multiplex RT-PCR. The study included 127 blood samples from patients who diagnosis of acute leukemia was subsequently confirmed. In the comparison group, 87 samples of patients without oncohematological diagnosis were selected, including 31 samples (K1) with a normal blood formula and 56 samples (K2) with a violation of the cellular composition - anemia, leukocytosis and thrombocytopenia. RNA isolation and reverse transcription were performed using the Ribozol-D and Reverta-L kits (TsNIIE, Russia). Determination of the mRNA expression level of the WT1, BAALC, EVI1, PRAME and HMGA2 genes by multiplex real-time PCR using a homemade multiplex PCR kit. The mRNA level was characterized by high interindividual variation and did not correlate with the rate of circulating leukocytes or blood blasts. Expression of WT1 mRNA was observed in whole blood only in one patient from the control group and in 112 (88%) patients with leukemia and was combined with a decrease in the level of HMGA2 mRNA expression and BAALC mRNA values. In contrast to the control groups, patients with leukemia had higher levels of BAALC mRNA in AML and ALL, increased PRAME mRNA in AML and APL, but lower levels of HMGA2 in APL.

322. Clinical-Grade Metagenomics in Urinary Tract Infections: Improving Performance of Next-Generation Sequencing Assays Using Internal Controls and Machine Learning

Abstract Background Shotgun sequencing-based metagenomics is a useful approach to profiling microbiomes in environmental and patient samples. In a clinical setting, metagenomic techniques have the advantage of identifying organisms, which cannot be readily cultured or confirmed by other techniques. We have developed a clinical-grade, streamlined metagenomics-based pipeline that includes regulatory compliant method considerations, such as an internal control followed by a machine-based learning (ML) process to identify pathogens in urine samples. Methods We built an optimized novel end-to-end NGS assay pipeline that harnesses pathogen-specific genome data to detect bacterial species. We processed de-identified clinical urine specimens, collected from patients symptomatic for urinary tract infection (UTI). This workflow includes an IPC, QIACube-MDx extraction, library preparation and Illumina NextSeq 550 sequencing and a novel interpretable ML based analytic approach, Biotia-DX. Clinical culture results and qPCR were used as a baseline for the assay to train the ML model and to establish accuracy relative to the clinical standard of care. Results We clinically validated over 40 key uropathogens and conducted clinical studies of specificity, intra/inter reproducibility, accuracy in urine specimens (n=300), and limit of detection in E. coli, K. pneumoniae, P. mirabilis, S. aureus, E. faecalis and Candida. Additionally, the implementation of an internal control coupled with our Biotia-DX software provides an accurate (F1 score 94.3%) and highly sensitive clinical grade diagnostic tool. Conclusion Urine has historically presented a challenge for diagnostics via culturing, with a high rate of culture-negative results (∼30% on average). We improved the clinical utility of an NGS urine assay by leveraging an IPC and ML software. This decreased the rate of false positive species called in a sample relative to other NGS techniques and allows for greater sensitivity and taxonomic specificity. This assay may be especially useful for low colony-count or negative-culture samples to diagnose and guide patient treatment. Disclosures Mara Couto-Rodriguez, MS, Biotia Inc.: Employee of Biotia Inc. a for-profit biotechnology company David C. Danko, PhD, Biotia Inc.: Employee of Biotia Inc. a for-profit biotechnology company Xavier O. Jirau Serrano, MS, Biotia Inc.: Employee of Biotia Inc. a for-profit biotechnology company Taylor Paisie, MS, Biotia Inc.: Employee of Biotia Inc. a for-profit biotechnology company John C. Papciak, BS, Biotia Inc.: Employee of Biotia Inc. a for-profit biotechnology company Eszter Szollosi, BS, Biotia Inc.: Employee of Biotia Inc. a for-profit biotechnology company Christopher E. Mason, PhD, Biotia Inc.: Advisor/Consultant|Biotia Inc.: Board Member|Biotia Inc.: Ownership Interest Caitlin Otto, PhD, D(ABMM), Biotia Inc.: Advisor/Consultant Niamh B. O'Hara, PhD, Biotia Inc.: Board Member|Biotia Inc.: Ownership Interest Dorottya Nagy-Szakal, MD PhD, Biotia Inc.: Employee of Biotia Inc. a for-profit biotechnology company|Biotia Inc.: Stocks/Bonds.

Omics as a Tool to Help Determine the Effectiveness of Supplements.

There has been considerable interest in dietary supplements in the last two decades. Companies are releasing new specifics at an alarming pace, while dietary supplements are one of the less-studied substances released for public consumption. However, access to state-of-the-art and high-throughput techniques, such as the ones used in omics, make it possible to check the impact of a substance on human transcriptome or proteome and provide answers to whether its use is reasonable and beneficial. In this review, the main domains of omics are briefly introduced. The review focuses on the three most widely used omics techniques: NGS, LC-MS, NMR, and their usefulness in studying dietary supplements. Examples of studies are described for some of the most commonly supplemented substances, such as vitamins: D, E, A, and plant extracts: resveratrol, green tea, ginseng, and curcumin extract. Techniques used in omics have proven to be useful in studying dietary supplements. NGS techniques are helpful in identifying pathways that change upon supplementation and determining polymorphisms or conditions that qualify for the necessity of a given supplementation. LC-MS techniques are used to establish the serum content of supplemented a compound and its effects on metabolites. Both LC-MS and NMR help establish the actual composition of a compound, its primary and secondary metabolites, and its potential toxicity. Moreover, NMR techniques determine what conditions affect the effectiveness of supplementation.

Clinical and Functional Implications of MYC Variants As a New Class of Pathogenic Variants in AML

MYC, a well-known oncogene, is implicated in a majority of cancers, but there is little data on its role in myeloid malignancies. We recently described a novel internal tandem duplication of MYC gene (MYC-ITD) in a subset of patients with AML. As the prevalence of MYC aberrations have not been well documented in AML, we interrogated the genome, transcriptome and associated clinical and laboratory data from the largest cohort of pediatric AML patients to define the prevalence, frequency of co-occurring cytomolecular alterations and outcomes associated with MYC variants. Mutation Profiling: Diagnostic specimens from 1,806 patients with AML (age 0-29 years) enrolled on COG Phase III trials were retrospectively interrogated using contemporary NGS techniques or a PCR based "Tandem Repeat" assay for MYC-ITD. Conventional karyotyping and mutational analysis, including NGS, were used to determine additional cytogenetic and molecular abnormalities. Of the 1,806 patients studied, MYC aberrations were identified in 58 patients (3.2%) with 50% (N=29) harboring MYC-ITD, 46.5% (N=27) with a SNV or indel (MYCSNV/indel) and 2 patients (3.5%) with dual MYC-ITD and SNV. For MYC-ITD, tandem duplications occurred in exon 3 (Max binding domain) with ITD lengths ranging from 252-588 bp. The majority of MYCSNV/indel (77%) were identified at the P72-P78 hotspot with 33.3% (N=9) harboring the P74>L mutation and 18.5% (N=5) having the T73>N mutation. Functional Studies: Given the novelty of the ITD variant, we initially characterized the functional properties of MYC-ITD in vitro. Similar to wild-type (MYCWT), MYC-ITD is localized to the nucleus and requires Max to bind to specific DNA sequences (E-boxes). However, in contrast to MYCWT, MYC-ITD fails to recognize sequences containing a single E-box in vitro, but exhibits higher affinity toward sequences with two or more E-boxes. MYC-ITD is consistently more efficient in activating promoters with multiple E-boxes than MYCWT. Thus, MYC-ITD may possess different DNA-binding and protein-interacting properties, potentially leading to altered transcriptional regulation and biological output. Given the alterations in DNA binding properties, we evaluated the functional consequences of MYC-ITD in our cord blood stem cell/endothelial cell (EC) co-culture system. Normal cord blood stem cells were transduced with MYC-ITD vs. MYCWT and grown in an EC co-culture system. MYC-ITD transduced cord blood stem cells showed significantly higher proliferation compared to MYCWT or control GFP-transduced cells with proliferation advantage of 37-and 45-fold after 14 and 21 days in co-culture, respectively (p<0.001). Clinical Impact: Analysis of cooperating cytomolecular lesions revealed a striking difference between MYC-ITD and MYCSNV/indel. MYC-ITD was highly enriched in core-binding factor (CBF) AML found in 86% (N=25)[(N=18, 62%) with inv(16) and (N=7, 24%) with t(8;21)] (Figure 1A), vs. 26% in the MYCWT cohort and had a paucity of somatic mutations. Conversely, MYCSNV/indel was enriched in NUP98-NSD1 fusions (N=7, 27%), FLT3-ITD (N=10, 38%) and NPM1 mutations (N=9, 33%) (Figure 1A), which was significantly higher than the WT cohort. Patients with MYC-ITD had a morphologic CR rate after course 1 of 92.3% vs. 80% (p=0.249) in patients with MYCSNV/indel with a corresponding relapse rate of 24% and 52% (p=0.046). Lower CR and higher relapse reflects the higher proportion of patients with high-risk lesions (FLT3-ITD, NUP98-NSD1 and WT1) in MYCSNV/indel and favorable CBF in MYCITD. Those with MYC-ITD and MYCSNV/indel had a 5-year event free survival (EFS) of 70% vs. 38.5%, respectively (p=0.018) with a corresponding overall survival (OS) of 76% and 47% (p=0.023) similar to patients with favorable or high risk disease (Figure 1B). Conclusion: Here we define MYC aberrations as a new class of pathogenic variants in childhood AML. We demonstrate functional and clinical characterization of a novel MYC-ITD and contrast this novel variant to that of established pathogenic MYCSNV/indel. We show the high prevalence of co-occurring core-binding factor fusions with MYC-ITD, and high frequency of co-occurring NUP98-NSD1, FLT3-ITD and NPM1 mutations in MYCSNV/indel. Patients with MYC-ITD have superior clinical outcomes while patients with MYCSNV/indel have clinical outcomes similar to high-risk patients, likely due to the associations with the disease associated fusions. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Metatranscriptomic Approach to Understand the Role of the Rhizosphere Microbiome: A Review

Plant roots harbour diverse microorganisms that interact with each other and the plants. Rhizosphere is the region of soil, closely associated with plant root. The microbiome associated with them is termed as rhizobiome. Its studies give insights into the roles of the microorganisms in plant health. With the advancement of NGS techniques, the identification of the non-cultural species has turned out to be possible. Sequencing of the whole genomic D.N.A. (metagenomics) can easily identify the taxonomic and functional profile but identification of the active and inactive members of the microbiome is not fulfilled. Meta-transcriptomics helps in determining the active functional profile of a microbial community by identifying the genes expressed by the entire microbial community. The general workflow is sampling, RNA extraction, library preparation, sequencing, pre-processing of data, assembly, taxonomic/functional profiling and the differential expression analysis. There exist numerous challenges, that can be overcome through enhanced sequencing technologies and algorithms.

PD-L1 expression, tumor mutational burden, and immune cell infiltration in non-small cell lung cancer patients with epithelial growth factor receptor mutations.

BackgroundImmunotherapy using programmed cell death protein 1/programmed death-ligand 1 (PD-1/PD-L1) inhibitors seems less effective in non-small cell lung cancer (NSCLC) patients with epithelial growth factor receptor (EGFR) mutations. Varied responses to PD-1/PD-L1 inhibitors have recently been observed in NSCLC patients harboring different types of EGFR mutations. Some EGFR-mutated NSCLC patients may benefit from PD-1/PD-L1 inhibitors. At present, PD-L1 expression, tumor mutational burden (TMB), and tumor immune microenvironment (TIME) are biomarkers for predicting the efficacy of PD-1/PD-L1 inhibitors in NSCLC patients. We retrospectively evaluated PD-L1 expression, TMB, and immune cell infiltration in NSCLC patients with EGFR mutation subtypes.MethodsPD-L1 expression, TMB, and the abundance of immune cell infiltration in NSCLC patients were evaluated in public databases and clinical samples. TMB was detected using the NGS technique, PD-L1 was detected using immunohistochemistry, and the abundance of immune cell infiltration in NSCLC samples was detected using multiple immunohistochemistry.ResultsPD-L1 expression and TMB were lower in EGFR-mutated NSCLCs than in wild-type patients. Differences in the abundance of immune cell infiltration were also observed between EGFR-mutated and wild-type NSCLC. The expression of PD-L1, TMB, and abundance of immune cell infiltration were different in patients harboring different subtypes of EGFR mutations. Patients with uncommon EGFR mutations, especially the G719X mutation, showed higher TMB and expressions of PD-L1 than classical EGFR mutations. M1 macrophages were higher in uncommon EGFR mutations than classical EGFR mutations.ConclusionsThe expression of PD-L1 and TMB in uncommon EGFR-mutated NSCLCs, especially the G719X mutation, were higher than those for classical EGFR-mutated NSCLCs and similar to EGFR wild-type. The abundance of immune cell infiltration in uncommon EGFR-mutated NSCLCs was similar to that in EGFR wild-type. Our findings suggest that uncommon EGFR-mutated NSCLCs may benefit from PD-1/PD-L1 inhibitors.