The Target Therapy Hyperbole: "KRAS (p.G12C)"-The Simplification of a Complex Biological Problem.

Kirsten Rat Sarcoma Viral Oncogene Homolog (KRAS) gene variations are linked to the development of numerous cancers, including non-small cell lung cancer (NSCLC), colorectal cancer (CRC), and pancreatic ductal adenocarcinoma (PDAC). The lack of typical drug-binding sites has long hampered the discovery of therapeutic drugs targeting KRAS. Since "CodeBreaK 100" demonstrated Sotorasib's early safety and efficacy and led to its approval, especially in the treatment of non-small cell lung cancer (NSCLC), the subsequent identification of specific inhibitors for the p.G12C mutation has offered hope. However, the CodeBreaK 200 study found no significant difference in overall survival (OS) between patients treated with Docetaxel and Sotorasib (AMG 510), adding another degree of complexity to this ongoing challenge. The current study compares the three-dimensional structures of the two major KRAS isoforms, KRAS4A and KRAS4B. It also investigates the probable structural changes caused by the three major mutations (p.G12C, p.G12D, and p.G12V) within Sotorasib's pocket domain. The computational analysis demonstrates that the wild-type and mutant isoforms have distinct aggregation propensities, resulting in the creation of alternate oligomeric configurations. This study highlights the increased complexity of the biological issue of using KRAS as a therapeutic target. The present study stresses the need for a better understanding of the structural dynamics of KRAS and its mutations to design more effective therapeutic approaches. It also emphasizes the potential of computational approaches to shed light on the complicated molecular pathways that drive KRAS-mediated oncogenesis. This study adds to the ongoing efforts to address the therapeutic hurdles presented by KRAS in cancer treatment.

Detección molecular de Mycoplasma pneumoniae en muestras respiratorias de niños hospitalizados.

Introducción: Actualmente se encuentra reportado que la infección por Mycoplasma pneumoniae (MP) puede darse en edades tempranas de la vida. Objetivo: Describir los hallazgos de la detección molecular de MP en secreciones respiratorias de pacientes que requirieron internación por infección respiratoria aguda, en un hospital pediátrico. Población y métodos: La recolección de datos se realizó mediante revisión de historias clínicas y la correlación estadística mediante test de chi-cuadrado. Se incluyeron 919 pacientes de un mes a catorce años y once meses de edad que requirieron internación por infección respiratoria aguda. Se analizó frecuencia por edad y sexo del asilamiento de MP conjuntamente con otros patógenos respiratorios. Resultados: MP fue el microorganismo más frecuentemente detectado (30 %), seguido del Virus Respiratorio Sincitial (VRS) (25.1 %). La edad y el sexo no se comportaron como predictor de la detección para MP. En un 47.3 % de los pacientes se aisló MP conjuntamente con otro patógeno, el más prevalente fue el VRS 31.3 %. En cuanto a los diagnósticos al egreso del grupo de pacientes con aislamiento de MP más otro microorganismo, el 50.8 % presentaron bronquiolitis, y en el grupo de pacientes con identificación solo de MP este porcentaje fue de 32.4 %. La diferencia de las distribuciones fue estadísticamente significativa (p<0.05). Conclusión: Concluimos que la detección MP es frecuente en nuestro medio y se presenta en un número importante de casos conjuntamente con otro patógeno respiratorio. Estos hallazgos deberían impulsar a continuar el estudio para determinar la relevancia clínica de los mismos.

Molecular detection of Mycoplasma pneumoniae in respiratory samples from hospitalized children / [Detección molecular de Mycoplasma pneumoniae en muestras respiratorias de niños hospitalizados.]

Introduction: It is currently reported that Mycoplasma pneumoniae (MP) infection can occur at a young age. Objective: Describe the findings of the molecular detection of MP in respiratory secretions of patients who required hospitalization due to acute respiratory infection, in a pediatric hospital. Population and methods: Data collection was performed by reviewing medical records and statistical correlation using the chi-square test. 919 patients from one month to fourteen years and eleven months of age who required hospitalization for acute respiratory infection were included. The frequency by age and sex of the isolation of MP was analyzed together with other respiratory pathogens. Results: Mycoplasma pneumoniae was the most frequently detected microorganism (30%), followed by respiratory syncytial virus (RSV) (25.1%). Age and sex did not behave as a predictor of detection for MP. In 47.3% of the patients, MP was isolated together with another pathogen, the most prevalent was RSV 31.3%. Regarding the diagnoses at discharge of the group of patients with isolation of MP and a another microorganism, 50.8% had bronchiolitis, and in the group of patients with identification only of MP this percentage was 32.4%. The difference in the distributions was statistically significant (p <0.05). Conclusion: We conclude that Mycoplasma pneumoniae detection is frequent in our environment and occurs in a significant number of cases together with another respiratory pathogen. These findings should prompt further study to determine their clinical relevance.

Introducción: Actualmente se encuentra reportado que la infección por Mycoplasma pneumoniae (MP) puede darse en edades tempranas de la vida. Objetivo: Describir los hallazgos de la detección molecular de MP en secreciones respiratorias de pacientes que requirieron internación por infección respiratoria aguda, en un hospital pediátrico. Población y métodos: La recolección de datos se realizó mediante revisión de historias clínicas y la correlación estadística mediante test de chi-cuadrado. Se incluyeron 919 pacientes de un mes a catorce años y once meses de edad que requirieron internación por infección respiratoria aguda. Se analizó frecuencia por edad y sexo del asilamiento de MP conjuntamente con otros patógenos respiratorios. Resultados: MP fue el microorganismo más frecuentemente detectado (30 %), seguido del Virus Respiratorio Sincitial (VRS) (25.1 %). La edad y el sexo no se comportaron como predictor de la detección para MP. En un 47.3 % de los pacientes se aisló MP conjuntamente con otro patógeno, el más prevalente fue el VRS 31.3 %. En cuanto a los diagnósticos al egreso del grupo de pacientes con aislamiento de MP más otro microorganismo, el 50.8 % presentaron bronquiolitis, y en el grupo de pacientes con identificación solo de MP este porcentaje fue de 32.4 %. La diferencia de las distribuciones fue estadísticamente significativa (p<0.05). Conclusión: Concluimos que la detección MP es frecuente en nuestro medio y se presenta en un número importante de casos conjuntamente con otro patógeno respiratorio. Estos hallazgos deberían impulsar a continuar el estudio para determinar la relevancia clínica de los mismos.

What Have We Learned from Patients Who Have Arboleda-Tham Syndrome Due to a De Novo KAT6A Pathogenic Variant with Impaired Histone Acetyltransferase Function? A Precise Clinical Description May Be Critical for Genetic Testing Approach and Final Diagnosis.

Pathogenic variants in genes are involved in histone acetylation and deacetylation resulting in congenital anomalies, with most patients displaying a neurodevelopmental disorder and dysmorphism. Arboleda-Tham syndrome caused by pathogenic variants in KAT6A (Lysine Acetyltransferase 6A; OMIM 601408) has been recently described as a new neurodevelopmental disorder. Herein, we describe a patient characterized by complex phenotype subsequently diagnosed using the clinical exome sequencing (CES) with Arboleda-Tham syndrome (ARTHS; OMIM 616268). The analysis revealed the presence of de novo pathogenic variant in KAT6A gene, a nucleotide c.3385C>T substitution that introduces a premature termination codon (p.Arg1129*). The need for straight multidisciplinary collaboration and accurate clinical description findings (bowel obstruction/megacolon/intestinal malrotation) was emphasized, together with the utility of CES in establishing an etiological basis in clinical and genetical heterogeneous conditions. Therefore, considering the phenotypic characteristics, the condition's rarity and the reviewed literature, we propose additional diagnostic criteria that could help in the development of future clinical diagnostic guidelines. This was possible thanks to objective examinations performed during the long follow-up period, which permitted scrupulous registration of phenotypic changes over time to further assess this rare disorder. Finally, given that different genetic syndromes are associated with distinct genomic DNA methylation patterns used for diagnostic testing and/or as biomarker of disease, a specific episignature for ARTHS has been identified.

An in silico pipeline approach uncovers a potentially intricate network involving spike SARS-CoV-2 RNA, RNA vaccines, host RNA-binding proteins (RBPs), and host miRNAs at the cellular level.

BACKGROUND: In the last 2 years, we have been fighting against SARS-CoV-2 viral infection, which continues to claim victims all over the world. The entire scientific community has been mobilized in an attempt to stop and eradicate the infection. A well-known feature of RNA viruses is their high mutational rate, particularly in specific gene regions. The SARS-CoV-2 S protein is also affected by these changes, allowing viruses to adapt and spread more easily. The vaccines developed using mRNA coding protein S undoubtedly contributed to the "fight" against the COVID-19 pandemic even though the presence of new variants in the spike protein could result in protein conformational changes, which could affect vaccine immunogenicity and thus vaccine effectiveness. RESULTS: The study presents the findings of an in silico analysis using various bioinformatics tools finding conserved sequences inside SARS-CoV-2 S protein (encoding mRNA) same as in the vaccine RNA sequences that could be targeted by specific host RNA-binding proteins (RBPs). According to the results an interesting scenario emerges involving host RBPs competition and subtraction. The presence of viral RNA in cytoplasm could be a new tool in the virus's armory, allowing it to improve its chances of survival by altering cell gene expression and thus interfering with host cell processes. In silico analysis was used also to evaluate the presence of similar human miRNA sequences within RBPs motifs that can modulate human RNA expression. Increased cytoplasmic availability of exogenous RNA fragments derived from RNA physiological degradation could potentially mimic the effect of host human miRNAs within the cell, causing modulation of the host cell network. CONCLUSIONS: Our in silico analysis could aid in shedding light on the potential effects of exogenous RNA (i.e. viruses and vaccines), thereby improving our understanding of the cellular interactions between virus and host biomolecules. Finally, using the computational approach, it is possible to obtain a safety assessment of RNA-based vaccines as well as indications for use in specific clinical conditions.

Assessment of submicroscopic genetic lesions by single nucleotide polymorphism arrays in a child with acute myeloid leukemia and FLT3-internal tandem duplication.

The same FLT3-internal tandem duplication (ITD) positive clone was detected at diagnosis and relapse, but not at birth, in a child with M1 acute myeloid leukemia. Single nucleotide polymorphism arrays demonstrated that chromosome 13 acquired uniparental disomy, in association with del(9q), represented a progressive event in the course of the disease, and it was responsible for the homozygous FLT3-ITD at relapse.

Nucleophosmin mutations in childhood acute myelogenous leukemia with normal karyotype.

Nucleophosmin (NPM) is a nucleocytoplasmic shuttling protein involved in leukemia-associated chromosomal translocations, and it regulates the alternate reading frame (ARF)-p53 tumor-suppressor pathway. Recently, it has been demonstrated that mutations of the NPM1 gene alter the protein at its C-terminal, causing its cytoplasmic localization. Cytoplasmic NPM was detected in 35% of adult patients with primary non-French-American-British (FAB) classification M3 acute myeloid leukemia (AML), associated mainly with normal karyotype. We evaluated the prevalence of the NPM1 gene mutation in non-M3 childhood AML patients enrolled in the ongoing Associazione Italiana di Ematologia e Oncologia Pediatrica (AIEOP-AML02) protocol in Italy. NPM1 mutations were found in 7 (6.5%) of 107 successfully analyzed patients. NPM1-mutated patients carried a normal karyotype (7/26, 27.1%) and were older in age. Thus, the NPM1 mutation is a frequent abnormality in AML patients without known genetic marker; the mutation may represent a new target to monitor minimal residual disease in AML and a potential candidate for alternative and targeted treatments.