RESUMEN
BACKGROUND: Breast cancer is a highly heterogeneous solid tumor, posing challenges in developing targeted therapies effective for all mammary carcinoma subtypes. WT1 emerges as a promising target for breast cancer therapy due to its potential oncogenic role in various cancer types. Previous works have yielded inconsistent results. Therefore, further studies are needed to clarify the behavior of this complex gene in breast cancer. METHODS AND RESULTS: In this study, we examined WT1 expression in both Formalin Fixed Paraffin Embedded breast tumors (n = 41) and healthy adjacent tissues (n = 41) samples from newly diagnosed cases of ductal invasive breast cancer. The fold change in gene expression between the tumor and healthy tissue was determined by calculating 2-∆∆Ct. Disease-free survival analysis was computed using the Kaplan-Meier method. To identify the expression levels of different WT1 isoforms, we explored the ISOexpresso database. Relative quantification of the WT1 gene revealed an overexpression of WT1 in most cases. The percentage of patients surviving free of disease at 8 years of follow-up was lower in the group overexpressing WT1 compared to the group with down-regulated WT1. CONCLUSIONS: Interestingly, this overexpression was observed in all molecular subtypes of invasive breast cancer, underscoring the significance of WT1 as a potential target in all these subtypes. The observed WT1 down-expression in a few cases of invasive breast cancer, associated with better survival outcomes, may correspond to the down-regulation of a particular WT1-KTS (-) isoform: the WT1 A isoform (EX5-/KTS-). The co-expression of this WT1 oncogenic isoform with a regulated WT1- tumor suppressor isoform, such as the major WT1 F isoform (EX5-/KTS +), could also explain such survival outcomes. Due to its capacity to adopt dual roles, it becomes imperative to conduct individual molecular expression profiling of the WT1 gene. Such an approach holds great promise in the development of personalized treatment strategies for breast cancer.
Asunto(s)
Neoplasias de la Mama , Proteínas WT1 , Femenino , Humanos , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Genes Supresores de Tumor , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas WT1/genética , Proteínas WT1/metabolismoRESUMEN
BACKGROUND: Coronavirus Disease 2019 (COVID-19) is a viral pandemic disease that may induce severe pneumonia in humans. In this paper, we investigated the putative implication of 12 vaccines, including BCG, OPV and MMR in the protection against COVID-19. Sequences of the main antigenic proteins in the investigated vaccines and SARS-CoV-2 proteins were compared to identify similar patterns. The immunogenic effect of identified segments was, then, assessed using a combination of structural and antigenicity prediction tools. RESULTS: A total of 14 highly similar segments were identified in the investigated vaccines. Structural and antigenicity prediction analysis showed that, among the identified patterns, three segments in Hepatitis B, Tetanus, and Measles proteins presented antigenic properties that can induce putative protective effect against COVID-19. CONCLUSIONS: Our results suggest a possible protective effect of HBV, Tetanus and Measles vaccines against COVID-19, which may explain the variation of the disease severity among regions.
Asunto(s)
Antígenos Virales/inmunología , SARS-CoV-2/química , Proteínas Virales/inmunología , Vacunas Virales/inmunología , Vacuna BCG , COVID-19 , Vacunas contra la COVID-19 , Simulación por Computador , Protección Cruzada , Humanos , Conformación ProteicaRESUMEN
Chloroquine/hydroxychloroquine have been proposed as potential treatments for COVID-19. These drugs have warning labels for use in individuals with glucose-6-phosphate dehydrogenase (G6PD) deficiency. Analysis of whole genome sequence data of 458 individuals from sub-Saharan Africa showed significant G6PD variation across the continent. We identified nine variants, of which four are potentially deleterious to G6PD function, and one (rs1050828) that is known to cause G6PD deficiency. We supplemented data for the rs1050828 variant with genotype array data from over 11,000 Africans. Although this variant is common in Africans overall, large allele frequency differences exist between sub-populations. African sub-populations in the same country can show significant differences in allele frequency (e.g. 16.0% in Tsonga vs 0.8% in Xhosa, both in South Africa, p = 2.4 × 10-3). The high prevalence of variants in the G6PD gene found in this analysis suggests that it may be a significant interaction factor in clinical trials of chloroquine and hydroxychloroquine for treatment of COVID-19 in Africans.
Asunto(s)
Tratamiento Farmacológico de COVID-19 , Cloroquina/efectos adversos , Deficiencia de Glucosafosfato Deshidrogenasa/genética , Glucosafosfato Deshidrogenasa/genética , Hidroxicloroquina/efectos adversos , África del Sur del Sahara/epidemiología , COVID-19/epidemiología , COVID-19/genética , Bases de Datos Genéticas , Variación Genética/genética , Deficiencia de Glucosafosfato Deshidrogenasa/tratamiento farmacológico , Deficiencia de Glucosafosfato Deshidrogenasa/epidemiología , Humanos , Mutación Missense/genética , Factores de RiesgoRESUMEN
We sought to determine the relative value of conventional molecular methods and whole-genome sequencing (WGS) for subtyping Salmonella enterica serovar Enteritidis recovered from 2000 to 2015 in Tunisia and to investigate the genetic diversity of this serotype. A total of 175 Salmonella Enteritidis isolates were recovered from human, animal, and foodborne outbreak samples. Pulsed-field gel electrophoresis (PFGE), multiple locus variable-number tandem repeat analysis (MLVA), and whole-genome sequencing were performed. Eight pulsotypes were detected for all isolates with PFGE (DI = 0.518). Forty-five Salmonella Enteritidis isolates were selected for the MLVA and WGS techniques. Eighteen MLVA profiles were identified and classified into two major clusters (DI = 0.889). Core genome multilocus typing (cgMLST) analysis revealed 16 profiles (DI = 0.785). Whole-genome analysis indicated 660 single-nucleotide polymorphism (SNP) divergences dividing these isolates into 43 haplotypes (DI = 0.997). The phylogenetic tree supported the classification of Salmonella Enteritidis isolates into two distinct lineages subdivided into five clades and seven subclades. Pairwise SNP differences between the isolates ranged between 302 and 350. We observed about 311 SNP differences between the two foodborne outbreaks, while only less or equal to 4 SNP differences within each outbreak. SNP-based WGS typing showed an excellent discriminatory power comparing with the conventional methods such as PFGE and MLVA. Besides, we demonstrate the added value of WGS as a complementary subtyping method to discriminate outbreak from non-outbreak isolates belonging to common subtypes. It is important to continue the survey of Salmonella Enteritidis lineages in Tunisia using WGS.
Asunto(s)
Tipificación Molecular , Infecciones por Salmonella/microbiología , Salmonella enteritidis/clasificación , Secuenciación Completa del Genoma , Animales , Electroforesis en Gel de Campo Pulsado , Enfermedades Transmitidas por los Alimentos/epidemiología , Enfermedades Transmitidas por los Alimentos/microbiología , Variación Genética , Humanos , Repeticiones de Minisatélite/genética , Filogenia , Polimorfismo de Nucleótido Simple , Infecciones por Salmonella/epidemiología , Salmonella enteritidis/genética , Salmonella enteritidis/aislamiento & purificación , Serogrupo , Túnez/epidemiologíaRESUMEN
Pharmacogenomics aims to reveal variants associated with drug response phenotypes. Genes whose roles involve the absorption, distribution, metabolism, and excretion of drugs, are highly polymorphic between populations. High coverage whole genome sequencing showed that a large proportion of the variants for these genes are rare in African populations. This study investigated the impact of such variants on protein structure to assess their functional importance. We used genetic data of CYP3A5 from 458 individuals from sub-Saharan Africa to conduct a structural bioinformatics analysis. Five missense variants were modeled and microsecond scale molecular dynamics simulations were conducted for each, as well as for the CYP3A5 wildtype and the Y53C variant, which has a known deleterious impact on enzyme activity. The binding of ritonavir and artemether to CYP3A5 variant structures was also evaluated. Our results showed different conformational characteristics between all the variants. No significant structural changes were noticed. However, the genetic variability seemed to act on the plasticity of the protein. The impact on drug binding might be drug dependant. We concluded that rare variants hold relevance in determining the pharmacogenomics properties of populations. This could have a significant impact on precision medicine applications in sub-Saharan Africa.
Asunto(s)
Simulación por Computador , Citocromo P-450 CYP3A/genética , Genética de Población , Genoma Humano , Fenotipo , Polimorfismo de Nucleótido Simple , África del Sur del Sahara , Genotipo , Humanos , Secuenciación Completa del GenomaRESUMEN
Glioblastoma is an aggressive cancer, against which medical professionals are still quite helpless, due to its resistance to current treatments. Scorpion toxins have been proposed as a promising alternative for the development of effective targeted glioblastoma therapy and diagnostic. However, the exploitation of the long peptides could present disadvantages. In this work, we identified and synthetized AaTs-1, the first tetrapeptide from Androctonus australis scorpion venom (Aa), which exhibited an antiproliferative effect specifically against human glioblastoma cells. Both the native and synthetic AaTs-1 were endowed with the same inhibiting effect on the proliferation of U87 cells with an IC50 of 0.56 mM. Interestingly, AaTs-1 was about two times more active than the anti-glioblastoma conventional chemotherapeutic drug, temozolomide (TMZ), and enhanced its efficacy on U87 cells. AaTs-1 showed a significant similarity with the synthetic peptide WKYMVm, an agonist of a G-coupled formyl-peptide receptor, FPRL-1, known to be involved in the proliferation of glioma cells. Interestingly, the tetrapeptide triggered the dephosphorylation of ERK, p38, and JNK kinases. It also enhanced the expression of p53 and FPRL-1, likely leading to the inhibition of the store operated calcium entry. Overall, our work uncovered AaTs-1 as a first natural potential FPRL-1 antagonist, which could be proposed as a promising target to develop new generation of innovative molecules used alone or in combination with TMZ to improve glioblastoma treatment response. Its chemical synthesis in non-limiting quantity represents a valuable advantage to design and develop low-cost active analogues to treat glioblastoma cancer.
Asunto(s)
Antineoplásicos/farmacología , Proliferación Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glioblastoma , Oligopéptidos/farmacología , Receptores de Formil Péptido/biosíntesis , Receptores de Lipoxina/biosíntesis , Venenos de Escorpión/química , Proteína p53 Supresora de Tumor/biosíntesis , Regulación hacia Arriba/efectos de los fármacos , Animales , Antineoplásicos/química , Glioblastoma/tratamiento farmacológico , Glioblastoma/metabolismo , Humanos , Oligopéptidos/química , EscorpionesRESUMEN
The spread of COVID-19 caused by the SARS-CoV-2 outbreak has been growing since its first identification in December 2019. The publishing of the first SARS-CoV-2 genome made a valuable source of data to study the details about its phylogeny, evolution, and interaction with the host. Protein-protein binding assays have confirmed that Angiotensin-converting enzyme 2 (ACE2) is more likely to be the cell receptor through which the virus invades the host cell. In the present work, we provide an insight into the interaction of the viral spike Receptor Binding Domain (RBD) from different coronavirus isolates with host ACE2 protein. By calculating the binding energy score between RBD and ACE2, we highlighted the putative jump in the affinity from a progenitor form of SARS-CoV-2 to the current virus responsible for COVID-19 outbreak. Our result was consistent with previously reported phylogenetic analysis and corroborates the opinion that the interface segment of the spike protein RBD might be acquired by SARS-CoV-2 via a complex evolutionary process rather than a progressive accumulation of mutations. We also highlighted the relevance of Q493 and P499 amino acid residues of SARS-CoV-2 RBD for binding to human ACE2 and maintaining the stability of the interface. Moreover, we show from the structural analysis that it is unlikely for the interface residues to be the result of genetic engineering. Finally, we studied the impact of eight different variants located at the interaction surface of ACE2, on the complex formation with SARS-CoV-2 RBD. We found that none of them is likely to disrupt the interaction with the viral RBD of SARS-CoV-2.
Asunto(s)
Betacoronavirus/química , Peptidil-Dipeptidasa A/química , Glicoproteína de la Espiga del Coronavirus/química , Secuencia de Aminoácidos , Enzima Convertidora de Angiotensina 2 , Sitios de Unión , COVID-19 , Infecciones por Coronavirus , Humanos , Simulación del Acoplamiento Molecular , Pandemias , Filogenia , Neumonía Viral , Dominios Proteicos , Estructura Terciaria de Proteína , SARS-CoV-2RESUMEN
Prostate cancer is the most highly diagnosed cancer in men worldwide. It is characterized by high proliferation, great invasion and metastatic potential. Sodium channel subtypes have been identified as highly expressed in different prostate cancer cell lines. In this study, we have screened the negatively charged fractions of Androctonus australis (Aa) scorpion venom to identify active peptides on DU145 prostate cancer cells proliferation. The most active compound was identified to be the sodium channel peptide AaHIV with an IC50 value of 15⯵M. At this concentration, AaHIV had low effect on the adhesion of DU145â¯cells to fibronectin. When compared to other Na+ channel Aa toxins, AaHIV was found to be 2 times more active than AaHI and AaHII on DU145â¯cells proliferation and slightly less active than AaHII on their adhesion. The three peptides are inactive on DU145â¯cells migration. AaHIV was found to be 16 times more active than veratridine, asteroidal alkaloid from plants of the lily family widely used as a sodium channel activator. Electrophysiological experiments showed that the AaHIV toxin activates Nav1.6 channel, suggesting that this sodium channel subtype is implicated in the proliferation of DU145 prostate cancer cells.
Asunto(s)
Neoplasias de la Próstata/patología , Venenos de Escorpión/farmacología , Animales , Adhesión Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Humanos , Masculino , Canal de Sodio Activado por Voltaje NAV1.6/efectos de los fármacos , Canal de Sodio Activado por Voltaje NAV1.6/metabolismo , Neoplasias de la Próstata/tratamiento farmacológico , Escorpiones , Canales de Sodio/efectos de los fármacos , Canales de Sodio/metabolismoRESUMEN
We previously reported that immunoreactivity of recombinant CFP32 (Rv0577), a virulence factor of Mycobacterium tuberculosis, was higher when produced in transformed Pichia pastoris as compared to transformed E. coli. In this study, we show that this difference is partly due to the N-glycosylation of the recombinant CFP32 (rCFP32) by the yeast Pichia pastoris. In addition, SDS-PAGE and western blotting analysis of Mycobacterium bovis BCG and yeast-produced rCFP32 showed the presence of a band corresponding to a homodimeric state of the protein, unlike that of rCFP32 produced in E. coli. Computational modeling indicates that a single cysteine residue at position 193 of each monomer might bond to stabilize the homodimeric state of CFP32. Computational study showed that this residue is buried inside the protein core of E. coli-produced rCFP32 suggesting that rCFP32 may adopt a different folding in P. pastoris and BCG, in which C193 is solvent exposed. Surprisingly, an enzyme-linked immunosorbent assay using a generated monoclonal antibody (14D4) reveals the presence of a differential epitope that appears to be the consequence of the protein dimerization of the yeast- and BCG-, but not E.coli- produced, CFP32 recombinant form. We conclude that, in addition to N-glycosylation, homodimeric folding significantly enhances the immunoreactivity of rCFP32 and may these post-translational modifications may factor into the structure and function of native M. tuberculosis CFP32.
Asunto(s)
Proteínas Bacterianas/química , Epítopos/química , Escherichia coli/genética , Mycobacterium tuberculosis/genética , Pichia/genética , Procesamiento Proteico-Postraduccional , Secuencia de Aminoácidos , Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/inmunología , Clonación Molecular , Epítopos/genética , Epítopos/inmunología , Escherichia coli/metabolismo , Expresión Génica , Vectores Genéticos/química , Vectores Genéticos/metabolismo , Glicosilación , Modelos Moleculares , Mycobacterium bovis/genética , Mycobacterium bovis/metabolismo , Mycobacterium tuberculosis/inmunología , Mycobacterium tuberculosis/metabolismo , Mycobacterium tuberculosis/patogenicidad , Pichia/metabolismo , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta , Pliegue de Proteína , Dominios y Motivos de Interacción de Proteínas , Multimerización de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Factores de VirulenciaRESUMEN
BACKGROUND: The resistance of melanoma cells to cisplatin restricts its clinical use. Therefore, the search for novel tumor inhibitors and effective combination treatments that sensitize tumor cells to this drug are still needed. We purified macrovipecetin, a novel heterodimeric C-type lectin, from Macrovipera lebetina snake venom and investigated its anti-tumoral effect on its own or combined with cisplatin, in human melanoma cells. METHODS: Biochemical characterization, in vitro cells assays such as viability, apoptosis, adhesion, migration, invasion, Western blotting and in silico analysis were used in this study. RESULTS: Macrovipecetin decreased melanoma cell viability 100 times more than cisplatin. Interestingly, when combined with the drug, macrovipecetin enhanced the sensitivity of SK-MEL-28 cells by augmenting their apoptosis through increased expression of the apoptosis inducing factor (AIF) and activation of ERK1/2, p38, AKT and NF-κB. Moreover, macrovipecetin alone or combined with cisplatin induced the expression of TRADD, p53, Bax, Bim and Bad and down-regulated the Bcl-2 expression and ROS levels in SK-MEL-28 cells. Interestingly, these treatments impaired SK-MEL-28 cell adhesion, migration and invasion through modulating the function and expression of αvß3 integrin along with regulating E-cadherin, vimentin, ß-catenin, c-Src and RhoA expression. In silico study suggested that only the α chain of macrovipecetin interacts with a region overlapping the RGD motif binding site on this integrin. CONCLUSIONS: We validated the antitumor effect of macrovipecetin when combined, or not, with cisplatin on SK-MEL-28 cells. GENERAL SIGNIFICANCE: The presented work proposes the potential use of macrovipecetin and cisplatin in combination as an effective anti-melanoma treatment.
Asunto(s)
Antineoplásicos/farmacología , Lectinas Tipo C/aislamiento & purificación , Melanoma/patología , Venenos de Víboras/química , Viperidae/metabolismo , Secuencia de Aminoácidos , Animales , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Antineoplásicos Alquilantes/farmacología , Apoptosis/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis/biosíntesis , Proteínas Reguladoras de la Apoptosis/genética , Adhesión Celular/efectos de los fármacos , Moléculas de Adhesión Celular/biosíntesis , Moléculas de Adhesión Celular/genética , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Cisplatino/farmacología , Resistencia a Antineoplásicos/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Sinergismo Farmacológico , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Integrina alfaVbeta3/efectos de los fármacos , Lectinas Tipo C/química , Modelos Moleculares , Simulación del Acoplamiento Molecular , Invasividad Neoplásica , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/genética , Conformación Proteica , Dominios y Motivos de Interacción de Proteínas , Mapeo de Interacción de Proteínas , Alineación de Secuencia , Homología de Secuencia de AminoácidoRESUMEN
Lebein, is an heterodimeric disintegrin isolated from Macrovipera lebetina snake venom that was previously characterized as an inhibitor of ADP-induced platelet aggregation. In this study, we investigated the effect of Lebein on the p53-dependent growth of human colon adenocarcinoma cell lines. We found that Lebein significantly inhibited LS174 (p53wt), HCT116 (p53wt), and HT29 (p53mut) colon cancer cell viability by inducing cell cycle arrest through the modulation of expression levels of the tumor suppression factor p53, cell cycle regulating proteins cyclin D1, CDK2, CDK4, retinoblastoma (Rb), CDK1, and cyclin-dependent kinase inhibitors p21 and p27. Interestingly, Lebein-induced apoptosis of colon cancer cells was dependent on their p53 status. Thus, in LS174 cells, cell death was associated with PARP cleavage and the activation of caspases 3 and 8 while in HCT116 cells, Lebein induced caspase-independent apoptosis through increased expression of apoptosis inducing factor (AIF). In LS174 cells, Lebein triggers the activation of the MAPK ERK1/2 pathway through induction of reactive oxygen species (ROS). It also decreased cell adhesion and migration to fibronectin through down regulation of α5ß1 integrin. Moreover, Lebein significantly reduced the expression of two angiogenesis stimulators, Vascular Endothelial Growth Factor (VEGF) and Neuropilin 1 (NRP1). It inhibited the VEGF-induced neovascularization process in the quail embryonic CAM system and blocked the development of human colon adenocarcinoma in nude mice. Overall, our work indicates that Lebein may be useful to design a new therapy against colon cancer. © 2016 Wiley Periodicals, Inc.
Asunto(s)
Antineoplásicos/uso terapéutico , Proliferación Celular/efectos de los fármacos , Neoplasias del Colon/tratamiento farmacológico , Regulación hacia Abajo/efectos de los fármacos , Neovascularización Patológica/tratamiento farmacológico , Factor A de Crecimiento Endotelial Vascular/genética , Venenos de Víboras/uso terapéutico , Animales , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Pollos , Colon/efectos de los fármacos , Colon/metabolismo , Colon/patología , Neoplasias del Colon/genética , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Humanos , Integrina beta1/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Ratones Desnudos , Modelos Moleculares , Neovascularización Patológica/genética , Neovascularización Patológica/metabolismo , Neovascularización Patológica/patología , Especies Reactivas de Oxígeno/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Venenos de Víboras/farmacologíaRESUMEN
The purified (phospho)lipase of Fusarium solani (FSL), was known to be active on both triglycerides and phospholipids. This study aimed at assessing the potential of this enzyme in hydrolyzing galactolipids. FSL was found to hydrolyze at high rates of synthetic medium chains monogalactosyldiacylglycerol (4658±146U/mg on DiC8-MGDG) and digalactosyldiacylglycerol (3785±83U/mg on DiC8-DGDG) and natural long chain monogalactosyldiacylglycerol extracted from leek leaves (991±85U/mg). It is the microbial enzyme with the highest activity on galactolipids identified so far with a level of activity comparable to that of pancreatic lipase-related protein 2. FSL maximum activity on galactolipids was measured at pH8. The analysis of the hydrolysis product of natural MGDG from leek showed that FSL hydrolyzes preferentially the ester bond at the sn-1 position of galactolipids. To investigate the structure-activity relationships of FSL, a 3D model of this enzyme was built. In silico docking of medium chains MGDG and DGDG and phospholipid in the active site of FSL reveals structural solutions which are in concordance with in vitro tests.
Asunto(s)
Hidrolasas de Éster Carboxílico/química , Proteínas Fúngicas/química , Fusarium/química , Fosfolipasas/química , Hidrolasas de Éster Carboxílico/genética , Hidrolasas de Éster Carboxílico/metabolismo , Dominio Catalítico , Pruebas de Enzimas , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fusarium/enzimología , Galactolípidos/síntesis química , Galactolípidos/química , Galactolípidos/aislamiento & purificación , Expresión Génica , Humanos , Concentración de Iones de Hidrógeno , Hidrólisis , Cinética , Lipasa/química , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Cebollas/química , Fosfolipasas/genética , Fosfolipasas/metabolismo , Hojas de la Planta/química , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Especificidad por SustratoRESUMEN
As one of the key tools on the precision medicine workbench, high-throughput genetic testing has enormous promise for improving healthcare outcomes. Tunisia has made tremendous progress in acquiring and implementing the technology in the clinical context. However, current utilization does not ensure the whole range of benefits that high-throughput genomic testing provides which impedes the country's ability to move forward into the new era of precision medicine. This issue is primarily related to the current state of Tunisia's healthcare ecosystem and the sociological attributes of its population, creating numerous challenges that must be addressed. In the current review, we aimed to identify and highlight these challenges that may be prevalent in other low and middle-income countries. Essentially, they fall into three main categories that include the socio-economic landscape in Tunisia, which prevents citizens from engaging in precision medicine activities; the current settings of the healthcare system that lack or miss key components for the successful implementation of precision medicine practices; and the inability of the current infrastructure and resources to handle the various challenges related to genomic data and metadata. We also propose five pillar solutions as a framework for addressing all of these challenges, which could strengthen Tunisia's capability for effective precision medicine implementation in today's clinical environment.
RESUMEN
BACKGROUND: The advent of high-throughput technologies, including cutting-edge sequencing devices, has revolutionized biomedical data generation and processing. Nevertheless, big data applications require novel hardware and software for parallel computing and management to handle the ever-growing data size and analysis complexity. On-premise, high-performance computing (HPC) is increasingly used in biomedical research for big data stewardship. FINDINGS: In this work, we present Tunisia's first high-performance computational infrastructure for omics research. METHOD: We highlight measurements and recommendations that may help institutions in other low- and middle-income countries that are eager to implement local HPC in facilities for bioinformatics research and omics data analyses.
Asunto(s)
Biología Computacional , Programas Informáticos , Biología Computacional/métodos , Países en Desarrollo , Humanos , Genómica/métodos , Macrodatos , Análisis de DatosRESUMEN
BACKGROUND: Leishmaniasis is responsible for approximately 65,000 annual deaths. Various Leishmania species are the predominant cause of visceral, cutaneous, or mucocutaneous leishmaniasis, affecting millions worldwide. The lack of a vaccine, emergence of resistance, and undesirable side effects caused by antileishmanial medications have prompted researchers to look for novel therapeutic approaches to treat this disease. Antimicrobial peptides (AMPs) offer an alternative for promoting the discovery of new drugs. METHODS: In this study, we detail the synthesis process and investigate the antileishmanial activity against Leishmania (Viannia) braziliensis for peptides belonging to the dermaseptin (DS) family and their synthetic analogs. The MTT assay was performed to investigate the cytotoxicity of these peptides on the murine macrophage cell line RAW 264.7. Subsequently, we performed molecular modeling analysis to explore the structure-function correlation of the derivatives interacting with the parasitic membrane. RESULTS: All examined derivatives displayed concentration-dependent antileishmanial effect at low concentrations. Their effectiveness varied according to the peptide's proprieties. Notably, peptides with higher levels of charge demonstrated the most pronounced activities. Cytotoxicity assays showed that all the tested peptides were not cytotoxic compared to the tested conventional drug. The structure-function relationships demonstrated that the charged N-terminus could be responsible for the antileishmanial effect observed on promastigotes. CONCLUSION: Collectively, these results propose that dermaseptins (DS) might offer potential as promising candidates for the development of effective antileishmanial therapies.
RESUMEN
Background: Cytochrome P450 (CYP) genetic variation largely impacts drug response. However, many CYP star alleles (haplotypes) lack functional annotation, impeding our understanding of drug metabolism mechanisms. We aimed to investigate the impact of missense variant combinations on CYP protein structures. Methods: Normal mode analysis was conducted on 261 missense variants within 91 CYP haplotypes. CYP2D6*2 and CYP2D6*17 were prioritized for molecular dynamics simulation. Results: Normal mode analysis and molecular dynamics highlight the effects of known CYP missense variants on protein stability and conformational dynamics. Missense variants within haplotypes may have intermodulating effects on protein structure and function. Conclusion: This study highlights the utility of multiscale modeling in interpreting CYP missense variants and particularly their combinations within various star alleles.
Asunto(s)
Citocromo P-450 CYP2D6 , Sistema Enzimático del Citocromo P-450 , Humanos , Citocromo P-450 CYP2D6/genética , Citocromo P-450 CYP2D6/metabolismo , Alelos , Sistema Enzimático del Citocromo P-450/genética , Haplotipos/genética , Mutación Missense/genéticaRESUMEN
Human papillomavirus type 16 (HPV-16) is the most prevalent HPV type worldwide and in Tunisia and the major carcinogenic HPV type found in cervical precancers and cancers. Previous studies have reported that genetic diversity of HPV16-E6 oncoprotein might be associated with cervical intraepithelial neoplasia progression. In this study we aimed to investigate the prevalence of HPV-16 E6 variants in precancerous lesions in Tunisian population to assess potential correlation with disease severity. Positive HPV cervical samples were obtained from the Laboratory of Anatomy Pathology of Pasteur Institute of Tunis. Cytological study was performed to identify cervical precancerous lesions. HPVs were typed using Reverse Line Hybridization. Only samples with HPV-16 single infection were selected for HP16-E6 genetic diversity investigation. HPV-16 E6 gene amplification was performed by PCR using specific primers and sequenced by Sanger Sequencing. The multiple alignment of generated sequences was performed using MEGAX software. Phylogenetic tree was constructed using Maximum Likehood method. The ternary complex of E6, E6AP and p53 core domain was used to perform in silico point mutations and thermodynamic calculations to assess stability and binding affinity. Genetic analysis of Tunisian E6-HPV16 sequences showed the presence of three lineages: European (A), African (C) and Asian American (D). Interestingly, the EUR variants were identified as the dominant lineage of HPV-16 and HPV-16 E6 350 G (L83V) was the most detected mutation in precancerous lesions. Modelling data showed that African variants induced the largest destabilizing effect on E6 structure and decreasing thereby in the affinity toward E6AP. Therefore, women infected with European variants are associated with low and high intraepithelial lesions. The findings give useful information for personalized decision algorithms of intra-epithelial cervical neoplasia in Tunisian women.
Asunto(s)
Proteínas Oncogénicas Virales , Infecciones por Papillomavirus , Lesiones Precancerosas , Neoplasias del Cuello Uterino , Femenino , Humanos , Papillomavirus Humano 16/genética , Proteínas Oncogénicas Virales/genética , Proteínas Oncogénicas Virales/metabolismo , Filogenia , Polimorfismo Genético , Lesiones Precancerosas/genética , Lesiones Precancerosas/virología , Neoplasias del Cuello Uterino/genética , Neoplasias del Cuello Uterino/virologíaRESUMEN
Hackathons are collaborative events that bring together diverse groups to solve predefined challenges. The COVID-19 pandemic caused by SARS-CoV-2 has emphasized the need for portable and reproducible genomics analysis pipelines to study the genetic susceptibility of the human host and investigate human-SARS-CoV-2 protein interactions. To build and strengthen institutional capacities in OMICS data analysis applied to host-pathogen interaction (HPI), the PHINDaccess project organized two hackathons in 2020 and 2021. These hackathons are aimed at developing bioinformatics pipelines related to the SARS-CoV-2 viral genome, its phylodynamic transmission, and the identification of human genome host variants, with a focus on addressing global health challenges, particularly in low- and middle-income countries (LMIC). This paper outlines the preparation, proceedings, and lessons learned from these hackathons, including the challenges faced by participants and our recommendations based on our experience for organizing hackathons in LMIC and beyond.
Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , SARS-CoV-2/genética , Países en Desarrollo , Pandemias , Interacciones Huésped-Patógeno/genéticaRESUMEN
Recent genomic studies have revealed the critical impact of genetic diversity within small population groups in determining the way individuals respond to drugs. One of the biggest challenges is to accurately predict the effect of single nucleotide variants and to get the relevant information that allows for a better functional interpretation of genetic data. Different conformational scenarios upon the changing in amino acid sequences of pharmacologically important proteins might impact their stability and plasticity, which in turn might alter the interaction with the drug. Current sequence-based annotation methods have limited power to access this type of information. Motivated by these calls, we have developed the Structural Workflow for Annotating ADME Targets (SWAAT) that allows for the prediction of the variant effect based on structural properties. SWAAT annotates a panel of 36 ADME genes including 22 out of the 23 clinically important members identified by the PharmVar consortium. The workflow consists of a set of Python codes of which the execution is managed within Nextflow to annotate coding variants based on 37 criteria. SWAAT also includes an auxiliary workflow allowing a versatile use for genes other than ADME members. Our tool also includes a machine learning random forest binary classifier that showed an accuracy of 73%. Moreover, SWAAT outperformed six commonly used sequence-based variant prediction tools (PROVEAN, SIFT, PolyPhen-2, CADD, MetaSVM, and FATHMM) in terms of sensitivity and has comparable specificity. SWAAT is available as an open-source tool.
RESUMEN
Precision medicine uses genomic guidance to improve drug treatment safety and efficacy. Prior knowledge of genetic variant impact can enable such strategies, but current knowledge of African variants remains scarce. G6PD variants are linked to haemolytic adverse effects for a number of drugs commonly used in African populations. We have investigated a set of G6PD variants with structural bioinformatics techniques to further characterise variants with known effect, and gain insights into variants with unknown impact. We observed wide variations in patterns of root-mean-square deviation between wild-type and variant structures. Variants with known, highly deleterious impact show structural effects which may likely result in the destabilisation of the G6PD homodimer. The V68M and N126D variants (which are both common across African populations, and together form the A- haplotype) induce large conformational shifts in the catalytic NADP+ binding domain. We observed a greater impact for the haplotype than for each of the individual variants in these cases. A novel African variant (M207T) shows the potential to disrupt interactions within the protein core, urging further investigation. We explore how characterising the molecular impact of African G6PD variants can enable advanced strategies for precision medicine, as well as impact the use of novel therapeutics aiming to treat G6PD deficiency. This knowledge can assist in bridging current knowledge gaps, and aid to facilitate precision medicine applications in African populations.