Potential Clinical Significance Research Articles

Exercise-Induced Electrocardiographic Changes in Healthy Young Males with Early Repolarization Pattern

Background: Exercise-induced modifications in ECG parameters among individuals with an early repolarization pattern (ERP) have not been evaluated in detail. We aimed to assess this phenomenon, with potential associations with arrhythmogenesis. Methods: Twenty-three young, healthy males with ERP (ERP+) participated in this study, alongside a control group, which consisted of nineteen healthy males without ERP (ERP−). ECGs at baseline, at peak exercise (Bruce protocol), and during the recovery phase were analyzed and compared between the two groups. Results: The treadmill test demonstrated strong cardiovascular fitness, with similar chronotropic and pressor responses in both groups. In the baseline ECGs, the QRS complex and the QT interval were shorter in the ERP+ group. During exercise, the P-wave duration was significantly longer and the QRS was narrower in the ERP+ group. In the recovery phase, there was a longer P wave and a narrower QRS in the ERP+ group. During the treadmill test, the J wave disappeared or did not meet the criteria required for ERP diagnosis. Conclusions: The slowed intra-atrial conduction found during exercise could be predictive of atrial arrhythmogenesis in the setting of ERP. The disappearing of J waves during exercise, due to increased sympathetic activity, has potential clinical significance.

Dysregulation of a Subset of Circulating and Vesicle-Associated miRNA in Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive neoplasia, characterized by early metastasis, low diagnostic rates at early stages, resistance to drugs, and poor prognosis. There is an urgent need to better characterize this disease in order to identify efficient diagnostic/prognostic biomarkers. Since microRNAs (miRNAs) contribute to oncogenesis and metastasis formation in PDAC, they are considered potential candidates for fulfilling this task. In this work, the levels of two miRNA subsets (involved in chemoresistance or with oncogenic/tumor suppressing functions) were investigated in a panel of PDAC cell lines and liquid biopsies of a small cohort of patients. We used RT-qPCR and droplet digital PCR (ddPCR) to measure the amounts of cellular- and vesicle-associated, and circulating miRNAs. We found that both PDAC cell lines, also after gemcitabine treatment, and patients showed low amounts of cellular-and vesicle-associated miR-155-5p, compared to controls. Interestingly, we did not find any differences when we analyzed circulating miR-155-5p. Furthermore, vesicle-related miR-27a-3p increased in cancer patients compared to the controls, while circulating let-7a-5p, miR-221-3p, miR-23b-3p and miR-193a-3p presented as dysregulated in patients compared to healthy individuals. Our results highlight the potential clinical significance of these analyzed miRNAs as non-invasive diagnostic molecular tools to characterize PDAC.

Bactericidal and sterilizing activity of sudapyridine-clofazimine-TB47 combined with linezolid or pyrazinamide in a murine model of tuberculosis.

As an obligate aerobe, Mycobacterium tuberculosis relies on its branched electron transport chain (ETC) for energy production through oxidative phosphorylation. Regimens targeting ETC exhibit promising potential to enhance bactericidal activity against M. tuberculosis and hold the prospect of shortening treatment duration. Our previous research demonstrated that the bacteriostatic drug candidate TB47 (T) inhibited the growth of M. tuberculosis by targeting the cytochrome bc1 complex and exhibited synergistic activity with clofazimine (C). Here, we found synergistic activities between C and sudapyridine (S), a structural analog of bedaquiline (B). S has shown similar anti-tuberculosis efficacy and may share a mechanism of action with B, which inhibits ATP synthesis and the energy metabolism of bacteria. We evaluated the efficacy of SCT in combination with linezolid (L) or pyrazinamide (Z) using a well-established murine model of tuberculosis. Compared to the BPa(pretomanid)L regimen, SCT and SCTL demonstrated similar bactericidal and sterilizing activities. There was no significant difference in activity between SCT and SCTL. In contrast, SCZ and SCTZ showed much higher activities, with none of the 15 mice experiencing relapse after 2 months of treatment with either SCZ or SCTZ. However, T did not contribute to the activity of the SCZ. Our findings emphasize the efficacy and the potential clinical significance of combination therapy with ETC inhibitors. Additionally, cross-resistance exists not only between S and B but also between S/B and C. This is supported by our findings, as spontaneous S-resistant mutants exhibited mutations in Rv0678, which are associated with cross-resistance to B and C.

Bioinformatics-based analysis of potential therapeutic target genes for polycystic ovary syndrome.

The purpose of this study was to screen differentially expressed genes in PCOS using gene chip data and investigate the biological functions of these DEGs in PCOS. Additionally, the study aimed to analyze the potential clinical significance of these genes using clinical data. In this study, we first screened the DEGs related to PCOS by using the gene chip data (GSE5090) from GEO database. Target gene prediction software was used to predict the target genes for these DEGs, and their functional enrichment was analysed. Subsequently, the STRING online tool and Cytoscape software were utilized to identify key genes by constructing protein-protein interaction networks (PPI). In the analysis of the GSE5090 dataset, seventeen differentially expressed genes (DEGs) were identified. Functional enrichment analysis revealed that these DEGs are predominantly associated with biological functions related to polycystic ovary syndrome (PCOS). Moreover, the tissue-specific expression analysis highlighted immune system markers, with a notable difference observed in 18 of these markers, accounting for 20.5% of the total. By constructing PPI networks and key gene regulatory networks, a total of three genes (RPL13, LEP, and ANXA1) were identified as key genes. In addition, the column-line graphical model performed well in predicting the risk of PCOS. Using ROC curves, the model proved to be effective in diagnosis. This study represents the first application of a bioinformatics approach to identify and confirm high expression levels of RPL13, LEP, and ANXA1 in patients with Polycystic Ovary Syndrome (PCOS). These key genes-RPL13, LEP, and ANXA1-may present viable targets for therapeutic interventions in PCOS, underscoring their potential clinical importance.

ACE Phenotyping in Human Blood and Tissues: Revelation of ACE Outliers and Sex Differences in ACE Sialylation

Angiotensin-converting enzyme (ACE) metabolizes a number of important peptides participating in blood pressure regulation and vascular remodeling. Elevated ACE expression in tissues (which is generally reflected by blood ACE levels) is associated with an increased risk of cardiovascular diseases. Elevated blood ACE is also a marker for granulomatous diseases. Decreased blood ACE activity is becoming a new risk factor for Alzheimer’s disease. We applied our novel approach—ACE phenotyping—to characterize pairs of tissues (lung, heart, lymph nodes) and serum ACE in 50 patients. ACE phenotyping includes (1) measurement of ACE activity with two substrates (ZPHL and HHL); (2) calculation of the ratio of hydrolysis of these substrates (ZPHL/HHL ratio); (3) determination of ACE immunoreactive protein levels using mAbs to ACE; and (4) ACE conformation with a set of mAbs to ACE. The ACE phenotyping approach in screening format with special attention to outliers, combined with analysis of sequencing data, allowed us to identify patient with a unique ACE phenotype related to decreased ability of inhibition of ACE activity by albumin, likely due to competition with high CCL18 in this patient for binding to ACE. We also confirmed recently discovered gender differences in sialylation of some glycosylation sites of ACE. ACE phenotyping is a promising new approach for the identification of ACE phenotype outliers with potential clinical significance, making it useful for screening in a personalized medicine approach.

Overexpression of cyclin F/CCNF as an independent prognostic factor for poor survival in clear cell renal cell carcinoma

Cyclin F (encoded by CCNF gene) has been reported to be implicated in the pathobiology of several human cancers. However, its potential clinical significance in clear cell renal cell carcinoma (ccRCC) remains unknown. The present study aimed to evaluate the potential significance of cyclin F, assessed by immunohistochemical (IHC) staining and molecular (bioinformatics) techniques, as a prognostic marker in ccRCC in relation to clinicopathological features and outcomes. IHC staining was performed using two independent ccRCC tissue array cohorts, herein called tissue macroarray (TMA)_1 and tissue microarray (TMA)_2, composed of 108 ccRCCs and 37 histologically normal tissues adjacent to the tumor (NAT) and 192 ccRCCs and 16 normal kidney samples, respectively. The mRNA expression data were obtained from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) public datasets, followed by bioinformatics analysis of biological mechanisms underlying prognosis. The relationship between immune cell infiltration level and CCNF expression in ccRCC was investigated using the Tumor Immune Estimation Resource 2.0 (TIMER2) and Gene Expression Profiling Interactive Analysis 2 (GEPIA2). Cyclin F expression was significantly elevated in ccRCC lesions compared to both NAT and normal renal tissues. Likewise, CCNF mRNA was markedly increased in ccRCCs relative to non-cancerous tissues. In all analyzed cohorts, tumors with features of more aggressive behavior were more likely to display cyclin F/CCNF-high expression than low. Furthermore, patients with high cyclin F/CCNF expression had shorter overall survival (OS) times than those with low expression. In addition, multivariable analysis revealed that cyclin F/CCNF-high expression was an independent prognostic factor for poor OS in ccRCC. Enrichment analysis for mechanistically relevant processes showed that CCNF and its highly correlated genes initiate the signaling pathways that eventually result in uncontrolled cell proliferation. CCNF expression was also correlated with immune cell infiltration and caused poor outcomes depending on the abundance of tumor-infiltrating immune cells in ccRCC. Our findings suggest that cyclin F/CCNF expression is likely to have an essential role in ccRCC pathobiology through regulating multiple oncogenic signaling pathways and affecting the tumor immune microenvironment and may serve as prognostic biomarker and promising therapeutic target in ccRCC.

Potential Diagnostic and Clinical Significance of Selected Genetic Alterations in Glioblastoma.

Glioblastoma is currently considered the most common and, unfortunately, also the most aggressive primary brain tumor, with the highest morbidity and mortality rates. The average survival of patients diagnosed with glioblastoma is 14 months, and only 2% of patients survive 3 years after surgery. Based on our clinical experience and knowledge from extensive clinical studies, survival is mainly related to the molecular biological properties of glioblastoma, which are of interest to the general medical community. Our study examined a total of 71 retrospective studies published from 2016 through 2022 and available on PubMed that deal with mutations of selected genes in the pathophysiology of GBM. In conclusion, we can find other mutations within a given gene group that have different effects on the prognosis and quality of survival of a patient with glioblastoma. These mutations, together with the associated mutations of other genes, as well as intratumoral heterogeneity itself, offer enormous potential for further clinical research and possible application in therapeutic practice.

Blood Cell Count Ratios at Baseline are Associated with Initial Clinical Response to Clozapine in Treatment-Resistant, Clozapine-Naïve, Schizophrenia-Spectrum Disorder.

Clozapine is the recommended treatment for managing treatment-resistant schizophrenia (TRS), and immunological mechanisms may be involved in its unique antipsychotic efficacy. This study investigated whether baseline immune abnormalities measured with blood cell count ratios can predict the clinical response after initiating treatment with clozapine in patients with clozapine naïve TRS. A longitudinal design was developed, involving 32 patients diagnosed with treatment-resistant, clozapine-naïve schizophrenia-spectrum disorder. Patients were evaluated at baseline before clozapine starting and 8 weeks of follow-up. Psychopathological status and immune abnormalities (blood cell count ratios: neutrophil-lymphocyte ratio [NLR], monocyte-lymphocyte ratio [MLR], platelet-lymphocyte ratio [PLR] and basophil-lymphocyte ratio [BLR]) were evaluated in each visit. Baseline NLR (b=- 0.364; p=0.041) and MLR (b =- 0.400; p=0.023) predicted the change in positive symptoms over the 8-week period. Patients who exhibited a clinical response showed higher baseline NLR (2.38±0.96 vs. 1.75±0.83; p=0.040) and MLR (0.21±0.06 vs. 0.17±0.02; p=0.044) compared to non-responders. In the ROC analysis, the threshold points to distinguish between responders and non-responders were approximately 1.62 for NLR and 0.144 for MLR, yielding AUC values of 0.714 and 0.712, respectively. No statistically significant differences were observed in the blood cell count ratios from baseline to the 8-week follow-up. Our study emphasizes the potential clinical significance of baseline NLR and MLR levels as predictors of initial clozapine treatment response in patients with TRS. Future studies with larger sample sizes and longer follow-up periods should replicate our findings.

Acetazolamide encapsulation in elastin like recombinamers using a supercritical antisolvent (SAS) process for glaucoma treatment

Glaucoma, the second most common cause of blindness worldwide, requires the development of new and effective treatments. This study introduces a novel controlled-release system utilizing elastin-like recombinamers (ELR) and the Supercritical Antisolvent (SAS) technique with supercritical CO2. Acetazolamide (AZM), a class IV drug with limited solubility and permeability, is successfully encapsulated in an amphiphilic ELR at three different ELR:AZM ratios, yielding up to 62 %. Scanning electron microscopy (SEM) reveals spherical microparticles that disintegrate into monodisperse nanoparticles measuring approximately 42 nm under physiological conditions. The nanoparticles, as observed via Transmission Electron Microscopy (TEM) and Atomic Force Microscopy (AFM), do not exhibit aggregates, a fact confirmed by the zeta potential displaying a value of –33 mV over a period of 30 days. Transcorneal permeation tests demonstrate a 10 % higher permeation level compared to the control solution, which increases to 30 % after 2 h. Ocular irritation tests demonstrate no adverse effects or damage. Intraocular pressure (IOP) tests conducted on hypertensive rabbits indicate greater effectiveness for all three analyzed formulations, suggesting enhanced drug bioavailability during treatment. Consequently, the combination of recombinant biopolymers and high-pressure techniques represents a promising approach for advancing glaucoma therapy, emphasizing its potential clinical significance.

The role of calcification in predicting invasion of thymoma to adjacent organs.

Thoracoscopic procedures such as video-assisted thoracoscopic surgery (VATS) and robot-assisted thoracoscopic surgery (RATS) have gained popularity for the treatment of thymoma. Accurate preoperative assessments of tumor invasion are crucial to identifying the appropriate surgical approach. Although imaging techniques have been used to predict invasion, a quantifiable method is still needed in clinical practice. The ubjects of this retrospective study were 226 patients with thymoma who underwent surgery at our hospital. Clinicopathological data, tumor staging, and recurrence rates were analyzed. Calcification identified through computed tomography (CT) defined the "calcified group" as having a long diameter of ≥ 5mm. Statistical analyses were performed to assess relationships and survival outcomes. The calcified group had higher Masaoka and World Health Organization classification than the noncalcified group, with significantly higher organ invasion rates. The calcified group also had remarkably higher recurrence rates. Thymoma calcification appears to correlate with increased invasiveness and recurrence rates, suggesting its potential as a predictor of tumor stage and prognosis. Despite its retrospective nature and inherent limitations, this study highlights the potential clinical significance of calcification in the surgical planning and prognostication of patients with thymoma.

The asynchronous dynamic changes and interrelationships between leukocyte composition and inflammatory markers and potential clinical significance in the early stage and sepsis stage in severe burns

ObjectiveThe aim of this study is to investigate the dynamic changes and interrelationships between leukocyte components and inflammatory markers in the early stages and sepsis stage in severe burns, and explore their potential clinical significance. MethodsThis is a 5-year retrospective cohort study involving 107 patients with severe burns (the total body surface area of burn (TBSA) > 50%), in which, neutrophil count, lymphocyte count, monocyte count, the ratio of the product of monocyte and lymphocyte count to neutrophil count (MLPN), procalcitonin (PCT), C-reactive protein (CRP), capillary leakage index (CLI) and creatinine (Scr) were investigated. ResultsWithin one week after injury, the leukocyte components and MLPN showed a V-shaped change, with a peak immediately after injury and a trough on the 4th or 5th day after injury, while CRP showed a continuous upward trend, and the leukocyte compositions of all patients were negatively correlated with CRP values. The counts of leukocytes components and CRP values in deceased patients were higher than those in surviving patients within 2 days after injury. In the resorption stage, although no significant difference in lymphocyte and monocyte counts between surviving and deceased patients was found, the monocyte and lymphocyte counts in deceased patients were lower than those in surviving patients on the 5th to 7th day after injury, while neutrophils counts and CRP values remained higher than those in surviving patients. And the dynamic changes of MLPN were consistent with those of leukocyte compositions and opposite to those of PCT values. Moreover, MLPN were negatively correlated with CRP, CLI, and Scr values in the early stage of severe burns. In sepsis stage, as the condition worsened, the values of CRP, PCT and neutrophil counts continuously increased with varying degree, while lymphocyte and monocyte counts, and MLPN showed continuously decrease, but rebounded to increase before death. And the occurrence of the trough of monocyte counts was earlier than that of lymphocyte counts, a negative correlation between neutrophil counts and PCT values was found. ConclusionThe results of this study revealed the dynamic interrelationships between leucocyte components and inflammatory indicators in the early stages and sepsis stage in severe burns, reflecting the different weightings of inflammatory responses and immune dysfunction in different disease stages and its correlation with outcomes, which providing useful clinical information for dynamic immunomodulatory therapy. Moreover, dynamic monitoring of MLPN value can provide timely information for clinical evaluation.

Potential role of lncRNA LOXL1-AS1 in human cancer development: a narrative review.

Long non-coding RNAs (lncRNAs) are a group of non-coding RNAs consisting of more than 200 nucleotides that are widely involved in various physiological and pathobiological processes in the body. LncRNA plays a crucial role in tumorigenesis and development with its unique functions, such as playing a role in a variety of biological processes of malignant tumors as a cancer-promoting factor or a cancer-suppressor factor. Lysyl oxidase-like protein 1-antisense RNA1 (LOXL1-AS1) is a novel functional lncRNA recently reported. This article reviews the current findings on the role of LOXL1-AS1 in cancer, and discusses the potential clinical significance and application prospects, in order to provide a theoretical basis and reference for the clinical diagnosis, treatment and screening of prognostic markers for malignant tumors. The PubMed and Embase databases were searched using the keywords "cancer" or "tumor" or "neoplasm" and "LOXL1-AS1" for publications from 2018 to the present. The English literature was searched, with a focus on relevant articles. These articles validated the role and mechanism of LOXL1-AS1 in different cancers. LOXL1-AS1 is a recently reported novel lncRNA, which is abnormally expressed and upregulated in more than ten cancers, and is positively correlated with adverse clinical features and poor prognosis in cancer patients. LOXL1-AS1 competently binds to a variety of microRNAs to regulate the expression of downstream target genes and regulate related signaling pathways, including proliferation, migration, invasion and inhibition of malignant biological behaviors such as apoptosis. LOXL1-AS1 is expected to become a novel biomarker for cancer diagnosis and treatment, with great potential as an independent prognostic indicator.

Genetic insights into the ‘sandwich fusion’ subtype of Klippel–Feil syndrome: novel FGFR2 mutations identified by 21 cases of whole-exome sequencing

BackgroundKlippel–Feil syndrome (KFS) is a rare congenital disorder characterized by the fusion of two or more cervical vertebrae during early prenatal development. This fusion results from a failure of segmentation during the first trimester. Although six genes have previously been associated with KFS, they account for only a small proportion of cases. Among the distinct subtypes of KFS, “sandwich fusion” involving concurrent fusion of C0-1 and C2-3 vertebrae is particularly noteworthy due to its heightened risk for atlantoaxial dislocation. In this study, we aimed to investigate novel candidate mutations in patients with “sandwich fusion.”MethodsWe collected and analyzed clinical data from 21 patients diagnosed with “sandwich fusion.” Whole-exome sequencing (WES) was performed, followed by rigorous bioinformatics analyses. Our focus was on the six known KFS-related genes (GDF3, GDF6, MEOX1, PAX1, RIPPLY2, and MYO18). Suspicious mutations were subsequently validated through in vitro experiments.ResultsOur investigation revealed two novel exonic mutations in the FGFR2 gene, which had not previously been associated with KFS. Notably, the c.1750A > G variant in Exon 13 of FGFR2 was situated within the tyrosine kinase domain of the protein, in close proximity to several established post-translational modification sites. In vitro experiments demonstrated that this certain mutation significantly impacted the function of FGFR2. Furthermore, we identified four heterozygous candidate variants in two genes (PAX1 and MYO18B) in two patients, with three of these variants predicted to have potential clinical significance directly linked to KFS.ConclusionsThis study encompassed the largest cohort of patients with the unique “sandwich fusion” subtype of KFS and employed WES to explore candidate mutations associated with this condition. Our findings unveiled novel variants in PAX1, MYO18B, and FGFR2 as potential risk mutations specific to this subtype of KFS.

A Retrospective Study of Biological Risk Factors Associated with Primary Knee Osteoarthritis and the Development of a Nomogram Model.

A high percentage of the elderly suffer from knee osteoarthritis (KOA), which imposes a certain economic burden on them and on society as a whole. The purpose of this study is to examine the risk of KOA and to develop a KOA nomogram model that can timely intervene in this disease to decrease patient psychological burdens. Data was collected from patients with KOA and without KOA at our hospital from February 2021 to February 2023. Initially, a comparison was conducted between the variables, identifying statistical differences between the two groups. Subsequently, the risk of KOA was evaluated using the Least Absolute Shrinkage and Selection Operator method and multivariate logistic regression to determine the most effective predictive index and develop a prediction model. The examination of the disease risk prediction model in KOA includes the corresponding nomogram, which encompasses various potential predictors. The assessment of disease risk entails the application of various metrics, including the consistency index (C index), the area under the curve (AUC) of the receiver operating characteristic curve, the calibration chart, the GiViTi calibration band, and the model for predicting KOA. Furthermore, the potential clinical significance of the model is explored through decision curve analysis (DCA) and clinical influence curve analysis. The study included a total of 582 patients, consisting of 392 patients with KOA and 190 patients without KOA. The nomogram utilized age, haematocrit, platelet count, apolipoprotein a1, potassium, magnesium, hydroxybutyrate dehydrogenase, creatine kinase, and estimated glomerular filtration rate as predictors. The C index, AUC, calibration plot, Giviti calibration band, DCA and clinical influence KOA indicated the ability of nomogram model to differentiate KOA. Using nomogram based on disease risk, high-risk KOA can be identified directly without imaging.

Circulating microbiome DNA as biomarkers for early diagnosis and recurrence of lung cancer

Lung cancer mortality is exacerbated by late-stage diagnosis. Emerging evidence indicates the potential clinical significance of distinct microbial signatures as diagnostic and prognostic biomarkers across various cancers. However, circulating microbiome DNA (cmDNA) profiles are underexplored in lung cancer (LC). Here, whole-genome sequencing is performed on plasma of LC patients and healthy controls (HCs). Differentially enriched microbial species are identified between LC and HC. A diagnostic model is developed, which has a high sensitivity of 87.7% and achieves an AUC of 93.2% in the independent validation dataset. Crucially, this model demonstrates the capability to detect early-stage LC, achieving a sensitivity of 86.5% for stage I and 87.1% for tumors <1cm. In addition, we construct a cmDNA model for recurrence, which precisely predicts LC recurrence after surgery. Overall, this study highlights the significant alterations of cmDNA profiles in LC, indicating its potential as biomarkers for early diagnosis and recurrence.

Identification and validation of key miRNAs and a microRNA-mRNA regulatory network associated with liver cancer

ABSTRACT MiRNAs play crucial regulatory roles in the growth and development of tumor cells by serving as carriers of post-transcriptional regulatory information derived from genes. Investigating the potential function and clinical significance of miRNA-mediated mRNA regulatory networks in liver cancer can offer novel insights and therapeutic strategies for the treatment of this disease. We identified 300 differentially expressed miRNAs, and five miRNAs were identified to be correlated with overall survival and could be used as an independent prognostic. GO enrichment analysis mainly included carboxylic acid biosynthesis, organic acid biosynthesis, peroxisomal membrane, microsomal membrane, DNA binding, C-acyltransferase activity, etc. KEGG enrichment analysis showed that the pathways of target genes related to liver cancer were mainly focused on butyric acid metabolism and partial amino acid metabolism. Eight of the top 10 HUB genes were associated with prognosis, and the expression of four genes was positively correlated with prognosis, of which ABAT, BHMT, and SHMT1 were target genes of hsa-miR-5003-3p. MiR-5003-3p inhibits ABAT/BHMT/SHMT1 expression, thereby promoting liver cancer development. Overall, our study provides new ideas for the treatment of liver cancer, and these five miRNAs may be independent prognostic biomarkers and therapeutic targets for liver cancer patients. And miR-5003-3p may be a critical factor in the mechanism of liver cancer development.

COMPARATIVE ANALYSIS OF STAGED VERSUS INDEX PROCEDURE COMPLETE REVASCULARIZATION IN ST-ELEVATION MYOCARDIAL INFARCTION

ST-elevation myocardial infarction (STEMI) is a critical condition that necessitates quick and efficient revascularization techniques. Recently, there has been a discussion on the best method for revascularization staged versus index procedure complete revascularization. The study compares the clinical outcomes of staged versus index procedure complete revascularization in ST-elevation myocardial infarction.  This study is a prospective comparative analysis conducted at Ayub Teaching Hospital, Abbottabad. The patients were divided into two groups, with 40 participants in each group. Demographic data that included Smoking history, Diabetes mellitus, Dyslipidemia, Previous MI, and (LVEF) was recorded. Intraoperative and postoperative outcomes at 72 hours and six months were recorded. The quality of life was also assessed using SF-36 16. Data was entered and analyzed using SPSS (Statistical Package for the Social Sciences) version 24. P-values of ≤0.05 will be considered statistically significant. These findings suggest that in Group A, the frequency of "No reflow" (1 case) and "Abrupt closure" (0 instances) p=0.02) compared to Group B, where "No reflow" was observed in 2 cases and "Abrupt closure" in 1 case, (and (p=0.01), the investigation into post-operative outcomes, revealed no statistically significant differences between the two groups. P values ranged from 0.31 to 0.45, indicating comparable outcomes. After six months post-surgery, Group A demonstrated significantly better outcomes across various health-related domains than Group B, as indicated by the SF-36 questionnaire. In conclusion, index complete vascularization holds a distinct advantage over staged procedures. The observed differences across various health indicators highlight the potential clinical significance of prioritizing complete revascularization during the initial intervention.

Klebsiella pneumoniae exhibiting a phenotypic hyper-splitting phenomenon including the formation of small colony variants.

In this study, we characterized a Klebsiella pneumoniae strain in a patient with shrapnel hip injury, which resulted in multiple phenotypic changes, including the formation of a small colony variant (SCV) phenotype. Although already described since the 1960s, there is little knowledge about SCV phenotypes in Enterobacteriaceae. The formation of SCVs has been recognized as a bacterial strategy to evade host immune responses and compromise the efficacy of antimicrobial therapies, leading to persistent and recurrent courses of infections. In this case, 14 isolates with different resisto- and morpho-types were distinguished from the patient's urine and tissue samples. Whole genome sequencing revealed that all isolates were clonally identical belonging to the K. pneumoniae high-risk sequence type 147. Subculturing the SCV colonies consistently resulted in the reappearance of the initial SCV phenotype and three stable normal-sized phenotypes with distinct morphological characteristics. Additionally, an increase in resistance was observed over time in isolates that shared the same colony appearance. Our findings highlight the complexity of bacterial behavior by revealing a case of phenotypic "hyper-splitting" in a K. pneumoniae SCV and its potential clinical significance.

Abstract 2856: Multi-omics approaches for biomarker discovery and target therapy in pediatric germ cell tumors

Abstract Pediatric germ cell tumors (GCT) are rare and heterogeneous, presenting various histologies. There are no specific markers for diagnosing GCT, and 30% of patients are resistant to standard cisplatin-based chemotherapy, which can be related to epithelial-mesenchymal transition (EMT). Therefore, this study aims to elucidate markers for classifying GCTs, evaluate the molecular mechanisms related to drug resistance, and search for new therapeutic approaches. The expression of miRNAs was assessed for 42 GCT-pediatric patients through miRNA Panel - Nanostring technology. Whole Exome Sequencing (WES) was performed for 16 GCT-pediatric patients to assess somatic mutations. In silico analysis of epithelial-mesenchymal transition (EMT) markers was performed using the cBioPortal database. The expression of EMT markers was evaluated in vitro in parental and cisplatin-resistant models (NTERA-2R). Xenograft model-derived NTERA-2R was established and EMT markers were also assessed. We identified specific miRNA expression signatures for each histology, including 34 miRNAs for dysgerminomas, 13 for embryonal carcinomas, 25 for yolk sac tumors, and one for immature teratoma. We identified 26 miRNAs that were commonly expressed in malignant tumors, with six miRNAs (miR-302a-3p, miR-302b-3p, miR-371a-5p, miR-372-3p, miR-373-3p, miR-367-3p) showing significant overexpression. MiR-302b-3p had a significant association with all the evaluated clinical features. WES analysis showed that Single Base Substitution signature 39 was observed in 68.75% of samples and SBS22 in 12.5%. Copy number alterations were identified in 4, 7, 8, 10, 12, 21, and 22 chromosomes, with amplification of CDKN1B, KRAS, CCND2, ETV6, and KDM5A genes and deletions of KIT and PTEN genes. Somatic mutations in NYAP2, RHBDF2, MTOR, KIT, ATM, KRAS, and PIK3CA were frequent among the samples. KIT (Asp816Val, Ala829Pro) and KRAS (Gln61Leu) mutations were classified with potential clinical significance and were validated. In silico analysis showed that different histologies had distinct expression profiles for EMT markers. Patients with SNAILlowSLUGlow expression had higher PFS than those with SNAILhighSLUGhigh (p=0.006). The median PFS of patients with SLUGlow was 46.4 months, while SLUGhigh was 28.0 months (p=0.022). In vitro analysis using NTERA-2R showed overexpression of EMT markers. The same result was obtained in the xenograft model derived from NTERA-2R. Our study offers vital insights into pediatric GCTs' molecular landscape, using in silico, in vitro, in vivo analyses, and genetic assessments, highlighting three points: 1) The miRNA signatures for each histology may have robust diagnostic and prognostic potential, besides clinical implications as biomarkers. 2) KIT and KRAS genes are possible therapeutic targets of pediatric GCTs. 3) EMT is related to cisplatin resistance and SLUG is a potential molecular target. Citation Format: Ana Flavia Souza Peres, Ingridy Izabella Vieira Cardoso, Janaina Mello Soares Galvao, Ana Glenda Santarosa Vieira, Marcela Nunes Rosa, Isabela Cristiane Tosi, Daniel Antunes Moreno, Ana Carolina Laus, Andre van Helvoort Lengert, Silvia Aparecida Teixeira, Adriane Feijo Evangelista, Rui Manuel Reis, Luiz Fernando Lopes, Mariana Tomazini Pinto. Multi-omics approaches for biomarker discovery and target therapy in pediatric germ cell tumors [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 2856.

Abstract 4893: Role of MGMT expression in the genomic landscape and immunogenicity in human colorectal carcinomas

Abstract Introduction: Colorectal cancer (CRC) is second most common cause of cancer-related mortality in the USA and most patients with advanced tumors lack effective therapeutic options. Epigenetic silencing resulting in reduced expression of O6-methylguanine-DNA methyltransferase (MGMT) has been described in diverse tumor types including CRC and it is linked with reduced DNA repair capability and increased sensitivity to alkylating agents such as temozolomide. However, the potential role and clinical significance of MGMT overexpression in cancer cells has not been studied. Methods: We used spatially resolved multiplex quantitative immunofluorescence (mQIF) analysis to concurrently measure the levels of MGMT protein, γH2AX and CD8+ tumor infiltrating lymphocytes (TILs) in a cohort of 111 CRCs and paired non-tumor colorectal mucosa from the same patient represented in tissue microarray format. To assess the genomic and immunologic context of MGMT expression, we studied the methylome, mutation profiling and mRNA expression of 526 CRCs from TCGA. The immunologic landscape of tumors was studied using GSEA and multiple transcriptomic-based tumor immune infiltration scores such as TIMER, CIBERSORT, etc. Finally, the genomic alterations and immunogenicity of SW620 human CRC cells (with baseline MGMT hypermethylation) with or without MGMT transfection were studied using in vitro co-culture preparations coupled to ultra-deep DNAseq and flow cytometry analysis. Results: On mQIF analysis, cancer-cell MGMT protein upregulation was identified in 73.9% of CRCs and was associated with reduced levels of γH2Ax in malignant cells and lower CD8+ TILs. 26.1% of cases showed MGMT protein downregulation. The genomic analysis of the TCGA cohort revealed that the mean nonsynonymous mutational load was significantly lower in MGMT-high than low tumors with marked differences in the type of variants and frequency of oncogenic mutations. The transcriptomic analysis revealed that MGMT overexpressing tumors showed lower immune infiltration than the MGMT-low group and reduced representation of immune associated signatures including interferon gamma response and TNF-alpha signaling. In contrast, DNA repair, TP53 pathways, were enriched. The exogenous expression of MGMT in SW620 cells reduced the number of nonsynonymous mutations by 15.6% (141 vs 119 mean mutations) and was also associated with low T-cell activation (CD69+/CD8+ T-cells) and cancer-cell elimination on allogenic co-cultures with human PBMCs. Conclusion: MGMT protein upregulation is common in human CRCs and is associated with reduced DNA damage response, distinct genomic features, and adaptive immune evasion. To our knowledge, this study is the first to report the biological and clinical characteristics of CRCs with MGMT overexpression that could support diagnostic and therapeutic developments. Citation Format: Barani Kumar Rajendran, Janie Zhang, Shruti Desai, Joanna Gibson, Jassim DiPalermo, Patricia LoRusso, Yong Kong, Hongyu Zhao, Michael Cecchini, Kurt Alex Schalper. Role of MGMT expression in the genomic landscape and immunogenicity in human colorectal carcinomas [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 4893.