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1.
Cancer Cell Int ; 24(1): 65, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336706

RESUMO

INTRODUCTION: Pediatric T-cell acute lymphoblastic leukemia (T-ALL) poses significant challenges due to its aggressive nature and resistance to standard treatments. Long non-coding RNAs (lncRNAs) have emerged as potential biomarkers and therapeutic targets in leukemia. This study aims to characterize the lncRNA landscape in pediatric T-ALL, identify specific lncRNAs signatures, and assess their clinical relevance. METHODS: RNA sequencing was performed on T-ALL patient and control samples. Differential expression analysis identified dysregulated lncRNAs and mRNAs. Functional enrichment analysis revealed potential roles of these lncRNAs in cancer pathogenesis. Validation of candidate lncRNAs was conducted using real-time PCR. Clinical correlations were assessed, including associations with patients' clinical characteristics and survival outcomes. RESULTS: Analysis identified 674 dysregulated lncRNAs in pediatric T-ALL, with LINC01221 and CRNDE showing the most interactions in cancer progression pathways. Functional enrichment indicated involvement in apoptosis, survival, proliferation, and metastasis. Top 10 lncRNAs based on adjusted p value < 0.05 and Fold Change > 2 were selected for validation. Seven lncRNAs LINC01221, PCAT18, LINC00977, RP11-620J15.3, RP11-472G21.2, CTD-2291D10.4, and CRNDE showed correlation with RNA sequencing data. RP11-472G21.2 and CTD-2291D10.4 were highly expressed in T-ALL patients, with RP11-620J15.3 correlating significantly with better overall survival (p = 0.0007) at a median follow up of 32 months. The identified lncRNAs were further analysed in B-ALL patients. Distinct lncRNAs signatures were noted, distinguishing T-ALL from B-ALL and healthy controls, with lineage-specific overexpression of LINC01221 (p < 0.0001), RP11-472G21.2 (p < 0.001) and CRNDE (p = 0.04) in T-ALL. CONCLUSION: This study provides insights into the lncRNA landscape of pediatric T-ALL, offering potential diagnostic and prognostic markers. RP11-620J15.3 emerges as a promising prognostic marker, and distinct lncRNAs signatures may aid in the differentiation of T-ALL subtypes. Further research with larger cohorts is warranted to validate these findings and advance personalized treatment strategies for pediatric T-ALL patients.

2.
BMC Cancer ; 24(1): 325, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38459434

RESUMO

INTRODUCTION: T-cell acute lymphoblastic leukemia (T-ALL) is a genetically heterogeneous disease with poor prognosis and inferior outcome. Although multiple studies have been perform on genomics of T-ALL, data from Indian sub-continent is scarce. METHODS: In the current study we aimed to identify the genetic variability of T-ALL in an Indian cohort of pediatric (age ≤ 12 years) T-ALL patients (n = 25) by whole transcriptome sequencing along with whole exome sequencing and correlated the findings with clinical characteristics and disease outcome. RESULTS: The median age was 7 years (range 3 -12 years). RNA sequencing revealed a definitive fusion event in 14 cases (56%) (including a novel fusions) with STIL::TAL1 in 4 (16%), followed by NUP21::ABL1, TCF7::SPI1, ETV6::HDAC8, LMO1::RIC3, DIAPH1::JAK2, SETD2::CCDC12 and RCBTB2::LPAR6 in 1 (4%) case each. Significant aberrant expression was noted in RAG1 (64%), RAG2 (80%), MYCN (52%), NKX3-1 (52%), NKX3-2 (32%), TLX3 (28%), LMO1 (20%) and MYB (16%) genes. WES data showed frequent mutations in NOTCH1 (35%) followed by WT1 (23%), FBXW7 (12%), KRAS (12%), PHF6 (12%) and JAK3 (12%). Nearly 88.2% of cases showed a deletion of CDKN2A/CDKN2B/MTAP genes. Clinically significant association of a better EFS and OS (p=0.01) was noted with RAG2 over-expression at a median follow up of 22 months, while a poor EFS (p=0.041) and high relapse rate (p=0.045) was observed with MYB over-expression. CONCLUSION: Overall, the present study demonstrates the frequencies of transcriptomic and genetic alterations from Indian cohort of pediatric T-ALL and is a salient addition to current genomics data sets available in T-ALL.


Assuntos
Leucemia-Linfoma Linfoblástico de Células T Precursoras , Criança , Humanos , Pré-Escolar , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Transcriptoma , Centros de Atenção Terciária , Fatores de Transcrição/genética , Mutação , Linfócitos T , Prognóstico , Forminas/genética , Histona Desacetilases , Proteínas Repressoras/genética , Receptores de Ácidos Lisofosfatídicos/genética
3.
Proc Natl Acad Sci U S A ; 117(10): 5394-5401, 2020 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-32094176

RESUMO

As a prototype of genomics-guided precision medicine, individualized thiopurine dosing based on pharmacogenetics is a highly effective way to mitigate hematopoietic toxicity of this class of drugs. Recently, NUDT15 deficiency was identified as a genetic cause of thiopurine toxicity, and NUDT15-informed preemptive dose reduction was quickly adopted in clinical settings. To exhaustively identify pharmacogenetic variants in this gene, we developed massively parallel NUDT15 function assays to determine the variants' effect on protein abundance and thiopurine cytotoxicity. Of the 3,097 possible missense variants, we characterized the abundance of 2,922 variants and found 54 hotspot residues at which variants resulted in complete loss of protein stability. Analyzing 2,935 variants in the thiopurine cytotoxicity-based assay, we identified 17 additional residues where variants altered NUDT15 activity without affecting protein stability. We identified structural elements key to NUDT15 stability and/or catalytical activity with single amino acid resolution. Functional effects for NUDT15 variants accurately predicted toxicity risk alleles in patients treated with thiopurines with far superior sensitivity and specificity compared to bioinformatic prediction algorithms. In conclusion, our massively parallel variant function assays identified 1,152 deleterious NUDT15 variants, providing a comprehensive reference of variant function and vastly improving the ability to implement pharmacogenetics-guided thiopurine treatment individualization.


Assuntos
Antimetabólitos/administração & dosagem , Antimetabólitos/toxicidade , Mercaptopurina/administração & dosagem , Mercaptopurina/toxicidade , Variantes Farmacogenômicos , Pirofosfatases/genética , Alelos , Substituição de Aminoácidos , Relação Dose-Resposta a Droga , Determinação de Ponto Final , Estabilidade Enzimática , Células HEK293 , Humanos , Mutação de Sentido Incorreto , Medicina de Precisão , Conformação Proteica em alfa-Hélice/genética , Pirofosfatases/química , Risco
4.
Blood Cells Mol Dis ; 87: 102510, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33197791

RESUMO

OBJECTIVE: In this study, clinico-hematological, genetic and outcome profile of children with BMF was evaluated to delineate the underlying genotype and phenotype. DESIGN: Cases were evaluated as two groups: Group 1 (n = 56; DBA-23, FA-18, DC-2, UBMFS-13) included children with suspected IBMFS based on clinical phenotype and accessible lab investigations and Group 2 (n = 53) included children with IAA treated with IST. Targeted NGS was carried out in a subset of these children (n = 42) and supplemented with WES wherever required. RESULTS: We identified causative mutation in overall 15 of 27 tested children (55.5%) in group 1 and 2 of 15 tested children (13.3%) in group 2. In DBA, a mutation was noted in 50% cases with involvement of RPS 19 (75%) and RPL5 (25%) genes. Phenotypic abnormalities were present in 69.5% and response to steroids in 68.4% of cases at a median follow up of 33 months. In children with IAA, overall response (complete + partial) was present in 51% at a median follow up of 23 months. The 3-year OS and FFS for the cohort of IAA were 68% and 48% respectively. Targeted sequencing could also pick up germline mutations in 50% of UBMFS cases and nearly 19% of IAA cases.


Assuntos
Transtornos da Insuficiência da Medula Óssea/genética , Anemia Aplástica/genética , Anemia Aplástica/patologia , Anemia Aplástica/terapia , Anemia de Diamond-Blackfan/genética , Anemia de Diamond-Blackfan/patologia , Anemia de Diamond-Blackfan/terapia , Transtornos da Insuficiência da Medula Óssea/patologia , Transtornos da Insuficiência da Medula Óssea/terapia , Criança , Pré-Escolar , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Imunossupressores/uso terapêutico , Lactente , Recém-Nascido , Masculino , Mutação , Sequenciamento do Exoma
5.
Blood Cells Mol Dis ; 89: 102569, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33930800

RESUMO

In current study, we discuss clinical oral iron refractoriness cases and highlight need for a classification system to define TMPRSS6 gene variants. Out of 231 cases of microcytic hypochromic anemia screened (Sept 2019-Dec 2020), 17 cases (7.35%) with unexplained iron refractoriness (URIDA) phenotype were enrolled after ruling out secondary causes and compliance related issues. 11 (65%) had absent/negligible response (0-0.4 g/dl Hb rise) while 6 (35%) partial (0.5-0.9 g/dl Hb rise) response to initial iron trial at 4-8 weeks. Of these 17 cases, inappropriate hepcidin levels (normal-high) were noted in 11/15 (73%) tested. TSAT/Hepcidin ratio was low in 13/15 (87%). Genetic analysis of TMPRSS6 gene by NGS revealed variations in 15/17 (88%) cases. 10/15 cases with variations harbored a common splice site INDEL that was noted to be pathogenic SNP (MAF-0.19) on case-control association study in combination with other known missense SNPs with an odds ratio of 6.38 and relative risk 2.66 (p- < 0.01).


Assuntos
Anemia Hipocrômica/tratamento farmacológico , Anemia Hipocrômica/genética , Ferro/uso terapêutico , Proteínas de Membrana/genética , Polimorfismo de Nucleotídeo Único , Serina Endopeptidases/genética , Administração Oral , Anemia Hipocrômica/sangue , Criança , Pré-Escolar , Feminino , Variação Genética , Hepcidinas/sangue , Humanos , Mutação INDEL , Lactente , Ferro/administração & dosagem , Masculino , Mutação de Sentido Incorreto
6.
BMC Gastroenterol ; 21(1): 327, 2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34425754

RESUMO

BACKGROUND: Polymorphisms in thiopurine methyltransferase (TPMT) and Nudix hydrolase-15 (NUDT15) have been implicated as the predominant cause of thiopurine induced leukopenia in the Western countries and East Asia respectively. Exact role of these polymorphisms in South Asian population with inflammatory bowel disease (IBD) is uncertain. METHODS: We included consecutive patients with IBD who were initiated on thiopurines at a center in North India. The dosage of thiopurines was titrated using regular monitoring of hemogram and liver function tests. Three TPMT polymorphisms (c.238 G > C, c.460 G > A, and c.719A > G) and one NUDT15 polymorphism (c.415 C > T) were assessed. Comparison regarding incidence of leukopenia and maximum tolerated thiopurine dosage was performed between those with wild polymorphism and those with TPMT and NUDT15 polymorphisms, respectively. RESULTS: Of the 119 patients (61 males, mean age 36.8 ± 13.5 years), 105 (88.2%) had ulcerative colitis and 14 (11.8%) had Crohn's disease. Leukopenia was noted in 33 (27.7%), gastrointestinal intolerance in 5 (4.2%) and pancreatitis in 2 (1.6%). TPMT polymorphisms were detected amongst five patients of whom 1 developed leukopenia. NUDT15 polymorphism was noted in 13 patients of whom 7 had leukopenia. The odds of developing leukopenia in TPMT polymorphism were non-significant (0.77, 95% CI:0.0822 to 7.2134, P = 0.819) but were significantly higher in those with NUDT15 polymorphism (3.5933, 1.1041 to 11.6951, P value: = 0.0336). CONCLUSION: NUDT15 polymorphism was more frequent than TPMT polymorphisms and was associated with thiopurine induced leukopenia. However, the tested polymorphisms account for only 24.2% of the risk of thiopurine induced leukopenia.


Assuntos
Doenças Inflamatórias Intestinais , Leucopenia , Metiltransferases/genética , Pirofosfatases/genética , Adulto , Humanos , Índia/epidemiologia , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/genética , Leucopenia/induzido quimicamente , Leucopenia/epidemiologia , Leucopenia/genética , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
7.
Blood Cells Mol Dis ; 82: 102356, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32171112

RESUMO

Langerhans cell histiocytosis (LCH) is an inflammatory myeloid neoplasia of children with systemic involvement and poor outcome. The altered RAS-RAF-MEK-ERK cell signalling pathway due to somatic mutation of BRAF V600E is the most common genetic abnormality associated with the disease. In the current study, we highlight the frequency of BRAF V600E in our cohort of LCH cases (n = 31) and its relation with clinical outcome. On Real-Time PCR and Sanger sequencing, BRAF V600E was detected in 6/31 (19%) patients. All cases positive for BRAF V600E mutation had multisystem involvement/disseminated disease compared to BRAF mutation negative cases (100% v/s 41%, p = 0.0348). Univariate analysis also revealed significant correlation of mutation positivity with risk category (p = 0.09). The event free survival and overall survival at 36 months for BRAF mutation positive group compared to mutation negative group was 17% v/s 72% (Log rank test p = 0.0110) and 32.5% v/s 82% (p = 0.0330), respectively. In our study, BRAF V600E positivity was low (19%) however, all positive cases had multisystem involvement and a poor three year survival confirming BRAF V600E to be a poor prognostic marker.


Assuntos
Histiocitose de Células de Langerhans/genética , Histiocitose de Células de Langerhans/mortalidade , Mutação de Sentido Incorreto , Proteínas Proto-Oncogênicas B-raf/genética , Substituição de Aminoácidos , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Humanos , Lactente , Masculino , Estudos Retrospectivos , Taxa de Sobrevida
8.
Blood Cells Mol Dis ; 82: 102419, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32179411

RESUMO

A comprehensive genotype-phenotype analysis of pediatric T-ALL data was performed. 33 confirmed pediatric (≤12 y) T-ALL samples were evaluated for oncogenic transcripts: TLX-1, TLX-3, common fusion of STIL-TAL1, NOTCH1 mutations and copy number variations (CNVs). Mean WBC was 235.69 × 103/µL. TLX1 and TLX-3 overexpression detected in 1 (3%) and 7 (21%) patients and STIL-TAL1 in 8 (27%). NOTCH1 mutations were noted in 17 (52%), of which 12 (71%) in HD domain and 6 (35%) in PEST domain (including one case with mutations in all three domains). Commonest CNVs were CDKN2A (85%) and CDKN2B (75%). Relapse occurred in 8 (24%) patients. The median follow-up was 15 months (range: 0.5-36). Bulky liver (p = 0.025), day 35 marrow (p = 0.004) and NOTCH mutation (p = 0.046) were predictive of time to an event. RFS was significantly poor for cases with PEST Vs. HD domain mutations (50% Vs. 85%) (p = 0.0009). Though cases with PEST domain NOTCH mutations had poor RFS, the OS was not influenced by NOTCH mutation positivity.


Assuntos
Mutação , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Receptor Notch1 , Criança , Pré-Escolar , Inibidor de Quinase Dependente de Ciclina p15/genética , Inibidor de Quinase Dependente de Ciclina p15/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Índia , Lactente , Masculino , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/mortalidade , Estudos Prospectivos , Domínios Proteicos , Receptor Notch1/genética , Receptor Notch1/metabolismo , Recidiva , Taxa de Sobrevida , Centros de Atenção Terciária
9.
J Pediatr Hematol Oncol ; 42(5): e299-e304, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31851072

RESUMO

BACKGROUND: The prognostic role of copy number variation is upcoming in Wilms tumor, and its identification will help in tailored therapy for improved cure. STUDY DESIGN: This was a retrospective, nested case-control, pilot study. MATERIALS AND METHODS: Formalin-fixed paraffin-embedded blocks of nephrectomy specimens were retrieved for the study and control groups (children with relapse and survivors for ≥2 y). Multiplex ligand probe amplification (MRC-Holland probe-mix P 380 A1) was performed, with 3 reference samples of normal kidney DNA run for every 7 cases. RESULTS: At least 1 variation was detected in 41 (97.8%) specimens. Loss of heterozygosity 1p was not observed. Loss of 16q, 1q gain, and MYCN gain were observed in 5 (11.9%), 29 (69%), and 39 (92.9%) specimens, respectively. The occurrence of copy number variations was similar in both groups: 1q gain: 15 versus 14 (P=1.0), 16q loss: 4 versus 1 (P=0.34), MYCN gain: 19 versus 20 (P=1.0). The gain of 1q, 16p loss, and MYCN gain did not differ across stage or age. CONCLUSIONS: The gain of 1q, MYCN gain, and 16p loss were identified. A higher occurrence of 1q gain and MYCN gain and a lack of difference in the distribution of variations among survivors and those with a relapse suggest a different molecular profile of Wilms tumor in Indian children.


Assuntos
Variações do Número de Cópias de DNA , Neoplasias Renais/patologia , Recidiva Local de Neoplasia/patologia , Tumor de Wilms/patologia , Estudos de Casos e Controles , Pré-Escolar , Feminino , Seguimentos , Humanos , Índia , Lactente , Neoplasias Renais/genética , Neoplasias Renais/cirurgia , Masculino , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/cirurgia , Nefrectomia , Projetos Piloto , Prognóstico , Estudos Retrospectivos , Tumor de Wilms/genética , Tumor de Wilms/cirurgia
10.
Mikrochim Acta ; 187(9): 490, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32767133

RESUMO

An inexpensive, effective, and efficient dispersive solid-phase extraction (DSPE) sorbent was developed as an alternative to traditionally used sorbents (primary secondary amine and C18) for fatty matrices using the QuEChERS method. Catalytic chemical vapor deposition grown carbon nanofibers dispersed on activated carbon fibers (Ni-ACF/CNF) having a BET specific surface area of 738 (m2/g) were for the first time evaluated as a DSPE material for sample cleanup before gas chromatographic analysis. Based on cleanup performance and recoveries, 10 mg of Ni-ACF/CNF was found optimal for the determination of twenty-seven multi-class pesticides in high fat and low water commodities/matrices (peanut, soybean, sesame, and flaxseed). The recoveries obtained for all analytes were in the range ~ 72 to ~ 117%, with relative standard deviation values ≤ 15%. The limits of detection and quantification values were 0.7-4.2 ng/g and 2.3-13.9 ng/g, respectively. The matrix match calibration curve was linear in the range 20-500 ng/g with a correlation coefficient of ≥ 0.993. The results reveal that the Ni-ACF/CNF is a competent DSPE sorbent, similar to primary secondary amines and C18 sorbent materials, for pesticide determination by QuEChERS methods in high fat and low water commodities. Graphical abstract.


Assuntos
Nanofibras/química , Resíduos de Praguicidas/análise , Extração em Fase Sólida/métodos , Adsorção , Carbono/química , Cromatografia Gasosa , Contaminação de Alimentos/análise , Limite de Detecção , Magnoliopsida/química , Resíduos de Praguicidas/química , Resíduos de Praguicidas/isolamento & purificação , Sementes/química
11.
Mol Cell Biochem ; 443(1-2): 101-110, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29147811

RESUMO

Here, we have studied in p53 null H1299 lung carcinoma cells, the dominant-negative effect of human p53 (h-p53) on buffalo p53 (b-p53) induced nuclear transactivation-dependent function. Recently, we have isolated and cloned the full-length cDNA of buffalo p53. Buffalo and human p53 proteins exhibit a high degree of structural and functional similarities. In transiently transfected H1299 cell line b-p53 appeared to be more sensitive to Mdm2-mediated degradation as compared to h-p53, although its ability to transactivate p21 promoter was stronger than that of the human counterpart. This higher transactivation ability of b-p53 was lost in the presence of h-p53 suggesting, a dominant-negative effect of h-p53 on b-p53's transactivation of p21 promoter. Both human and buffalo p53 proteins could hetero-oligomerize but the b-p53 could tetramerize much faster than the h-p53. A chimeric cDNA construct of human p53 was made where the 1-260 bp N-terminus was replaced with buffalo p53 counterpart and expressed in H1299 cell line. The tetramerization ability of the chimeric p53 protein was comparable to that of h-p53. Properties of b-p53 like stronger p21 transactivation and super sensitivity to Mdm2 mediated degradation were lacking in the chimeric protein. Thus, it is suggested that faster ability of tetramerization as well as higher transactivation property of buffalo p53 is determined by the interplay of N- and C-terminal domains through macromolecular interactions.


Assuntos
Inibidor de Quinase Dependente de Ciclina p21/biossíntese , Regiões Promotoras Genéticas , Multimerização Proteica , Ativação Transcricional , Proteína Supressora de Tumor p53 , Animais , Búfalos , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p21/genética , Humanos , Domínios Proteicos , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
12.
Mol Cell Biochem ; 408(1-2): 15-23, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26092425

RESUMO

Steroid 5-alpha reductase type 2 (SRD5A2) gene is important for normal development and functioning of prostate gland but it is reported to be silenced in metastatic prostate cancer. We showed that exogenous SRD5A2 expression in prostate cancer cell line reduced cell migration and invasion. Additionally, the stable transfectants showed enhanced adhesion to the matrix accompanied by changes in cytoskeletal organization, involving actin polymerization. siRNA knockdown of the endogenous SRD5A2 mRNA in LnCAP cells was effective, it reversed the phenotype, and thus induced cell motility. The MEK1 and pERK1/2 levels were found to be reduced in SRD5A2-expressing cells. Further, the reduced level of p38 protein was correlated with low expression of MMP-2 and MMP-7 genes. The results suggest that SRD5A2 controls cell migration by indirectly regulating ERK/MAPK pathway.


Assuntos
3-Oxo-5-alfa-Esteroide 4-Desidrogenase/genética , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/metabolismo , Actinas/metabolismo , Movimento Celular , Sistema de Sinalização das MAP Quinases , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Neoplasias da Próstata/metabolismo , Actinas/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Invasividade Neoplásica , Neoplasias da Próstata/genética
13.
Gene ; 895: 147981, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-37951373

RESUMO

The study highlights genomic findings in a series of 13 IRIDA phenotype cases. All had microcytic hypochromic anemia with suboptimal oral iron response to two different oral iron preparations at 4-6 weeks and low-normal ferritin, low transferrin saturation, and inappropriately high hepcidin. Targeted NGS on a 26-gene iron panel revealed pathogenic TMPRSS6 variants in 5/13 (38 %) cases. In addition, 2 (15 %) cases revealed rare SMAD4 and TBXAS1 gene variants that can present with refractory anemia but were consistent with diagnosis of hereditary hemorrhagic telangiectasia and Ghosal hematodiaphyseal dysplasia respectively.


Assuntos
Anemia Ferropriva , Humanos , Anemia Ferropriva/genética , Fenótipo , Ferro , Hepcidinas , Genômica , Doenças Raras , Proteínas de Membrana/genética , Serina Endopeptidases/genética
14.
J Mol Diagn ; 26(5): 430-444, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38360212

RESUMO

Inherited iron metabolism defects are possibly missed or underdiagnosed in iron-deficient endemic settings because of a lack of awareness or a methodical screening approach. Hence, we systematically evaluated anemia cases (2019 to 2021) based on clinical phenotype, normal screening tests (high-performance liquid chromatography, α gene sequencing, erythrocyte sedimentation rate, C-reactive protein, and tissue transglutaminase), and abnormal iron profile by targeted next-generation sequencing (26-gene panel) supplemented with whole-exome sequencing, multiplex ligation probe amplification/mitochondrial DNA sequencing, and chromosomal microarray. Novel variants in ALAS2, STEAP3, and HSPA9 genes were functionally validated. A total of 290 anemia cases were screened, and 41 (14%) enrolled for genomic testing as per inclusion criteria. Comprehensive genomic testing revealed pathogenic variants in 23 of 41 cases (56%). Congenital sideroblastic anemia was the most common diagnosis (14/23; 61%), with pathogenic variations in ALAS2 (n = 6), SLC25A38 (n = 3), HSPA9 (n = 2) and HSCB, SLC19A2, and mitochondrial DNA deletion (n = 1 each). Nonsideroblastic iron defects included STEAP3-related microcytic anemia (2/23; 8.7%) and hypotransferrenemia (1/23; 4.3%). A total of 6 of 22 cases (27%) revealed a non-iron metabolism gene defect on whole-exome sequencing. Eleven novel variants (including variants of uncertain significance) were noted in 13 cases. Genotype-phenotype correlation revealed a significant association of frameshift/nonsense/splice variants with lower presentation age (0.8 months versus 9 years; P < 0.01) compared with missense variants. The systematic evaluation helped uncover an inherited iron defect in 41% (17/41) of cases, suggesting the need for active screening and awareness for these rare diseases in an iron-deficient endemic population.


Assuntos
Anemia Sideroblástica , Ferro , Humanos , Lactente , Ferro/metabolismo , Mutação , Anemia Sideroblástica/epidemiologia , Anemia Sideroblástica/genética , Anemia Sideroblástica/diagnóstico , Genômica , DNA Mitocondrial , Proteínas de Membrana Transportadoras/genética , 5-Aminolevulinato Sintetase/genética , 5-Aminolevulinato Sintetase/metabolismo
15.
Cancer Chemother Pharmacol ; 92(1): 51-56, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37256334

RESUMO

PURPOSE: Thiopurine drugs like 6-Mercaptopurine (6MP) are the cornerstone of maintenance therapy in acute lymphoblastic leukemia (ALL). A recently described variant in alpha-ketoglutarate dependent dioxygenase (FTO) gene has been reported to play an important role in thiopurine induced myelosuppression. METHODS: In this study, we genotyped a coding variant (p.Ala134Thr, rs79206939) and an intronic variant (rs16952570) of FTO in 174 Indian children (age ≤ 12 years) with ALL on maintenance phase of chemotherapy and examined correlation with the risk of thiopurine induced myelosuppression and hepatic toxicity. RESULTS: The prevalence of FTO-rs16952570 polymorphism was 18.4% (32/174) with 142 (82%) cases having TT genotype, 26 (15%) cases with TC genotype and 6 (3.4%) cases having CC genotype. FTO-rs79206939 was absent and non-polymorphic in our study group. The mean dose of 6-MP during 36 weeks of maintenance of TT, TC and CC carriers of FTO-rs16952570 was 53.7, 53.6 and 54.1 mg/m2/day. Number of patients tolerating starting dose of 60 mg/m2/day was significantly higher in CC (50%) than TT/TC (14%) genotype carrying cases (p = 0.014). However, no statistical significance was observed for total leukocyte count (TLC), absolute neutrophil count (ANC) as well as for platelets counts in patients harboring FTO-rs16952570 TT/TC/CC genotype at 4, 8, 12, 24 and 36 weeks after start of thiopurine therapy. Further, no significant correlation was noted between number of weeks of chemotherapy interruptions or episodes of febrile neutropenia and no evidence of hepatotoxicity was found with the genotype studied. CONCLUSION: Polymorphism in FTO-rs16952570 did not show any correlation with thiopurine related toxicity in ALL patients.


Assuntos
Mercaptopurina , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Criança , Antimetabólitos Antineoplásicos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Polimorfismo Genético , Genótipo , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética
16.
Diagnostics (Basel) ; 13(5)2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-36900028

RESUMO

METHODS: Forty pediatric (0-12 years) B-ALL DNA samples (20 paired Diagnosis-Relapse) and an additional six B-ALL DNA samples (without relapse at 3 years post treatment), as the non-relapse arm, were retrieved from the biobank for advanced genomic analysis. Deep sequencing (1050-5000X; mean 1600X) was performed using a custom NGS panel of 74 genes incorporating unique molecular barcodes. RESULTS: A total 47 major clones (>25% VAF) and 188 minor clones were noted in 40 cases after bioinformatic data filtering. Of the forty-seven major clones, eight (17%) were diagnosis-specific, seventeen (36%) were relapse-specific and 11 (23%) were shared. In the control arm, no pathogenic major clone was noted in any of the six samples. The most common clonal evolution pattern observed was therapy-acquired (TA), with 9/20 (45%), followed by M-M, with 5/20 (25%), m-M, with 4/20 (20%) and unclassified (UNC) 2/20 (10%). The TA clonal pattern was predominant in early relapses 7/12 (58%), with 71% (5/7) having major clonal mutations in the NT5C2 or PMS2 gene related to thiopurine-dose response. In addition, 60% (3/5) of these cases were preceded by an initial hit in the epigenetic regulator, KMT2D. Mutations in common relapse-enriched genes comprised 33% of the very early relapses, 50% of the early and 40% of the late relapses. Overall, 14/46 (30%) of the samples showed the hypermutation phenotype, of which the majority (50%) had a TA pattern of relapse. CONCLUSIONS: Our study highlights the high frequency of early relapses driven by TA clones, demonstrating the need to identify their early rise during chemotherapy by digital PCR.

17.
Virchows Arch ; 483(4): 477-486, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37460674

RESUMO

BACKGROUND: Neuroblastoma (NB) is the most common extracranial solid tumour in childhood with a diverse clinical presentation and course. The early age of onset, high frequency of metastatic disease at diagnosis and tendency for spontaneous regression in infancy sets it apart from other childhood tumors. This heterogeneity is largely attributed to underlying genetic aberrations which are distinct in low-risk and high-risk NB. To this end, we sought to analyse our NB cases for the molecular alterations and find its correlation with clinical behaviour. METHODS: NB cases (n = 50) diagnosed over last 7 years were retrospectively analysed for MYCN amplification (fluorescent-in-situ hybridization), TERT rearrangements (qRT-PCR), ATRX mutations (immunohistochemistry). These findings were correlated with demographic profiles, histologic features and clinical outcome. RESULTS: Age ranged from 1 month to 30 years (mean 2.8 years) with male preponderance. Poorly differentiated subtype constituted the majority (64%), followed by differentiating (28%) and undifferentiated subtype (8%) which were equally distributed across all age groups. MYCN amplification, TERT-mRNA upregulation and ATRX mutations was observed in 30%, 42% and 24%, respectively. Cases with TERT-mRNA upregulation were distributed equally across all histological subtypes while those with ATRX mutations and MYCN amplification were frequent in poorly differentiated NB. ATRX mutation was mutually exclusive of TERT-mRNA upregulation and MYCN amplification. Kaplan-Meier analysis revealed significantly shorter overall and progression-free survival for tumors harboring MYCN amplification and TERT-mRNA upregulation, while that for ATRX mutant tumors was not significant. CONCLUSIONS: Our results provide data indicating poor clinical outcome in NB carrying MYCN amplification and TERT-mRNA upregulation.


Assuntos
Neuroblastoma , Telomerase , Humanos , Lactente , Masculino , Amplificação de Genes , Mutação , Proteína Proto-Oncogênica N-Myc/genética , Neuroblastoma/genética , Neuroblastoma/patologia , Estudos Retrospectivos , RNA Mensageiro , Telomerase/genética , Telomerase/metabolismo , Proteína Nuclear Ligada ao X/genética , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto
18.
J Mol Diagn ; 25(10): 748-757, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37474001

RESUMO

The current study is a 4-year experience in diagnosis and screening of inherited and immune bone marrow failure cases using a targeted sequencing panel. A total of 171 cases underwent targeted next-generation sequencing and were categorized as suspected inherited bone marrow failure syndrome (IBMFS) group (106; 62%) and immune/idiopathic aplastic anemia (IAA) group (65; 38%) based on clinical and laboratory criteria. A total of 110 (64%) were pediatric (aged 0 to 12 years) patients and 61 (36%) were adolescent and adult (aged 13 to 47 years) patients. In suspected IBMFS group, 47 (44%), and in IAA group, 8 (12%) revealed a likely germline pathogenic variation. Whole-exome sequencing performed in 15 of 59 suspected IBMFS group cases was negative on targeted panel, and revealed a clinically important variation in 3 (20%) cases. A total of 11 novel variants were identified. The targeted panel helped establish a diagnosis in 44% (27/61) of unclassified bone marrow failure syndrome cases and led to amendment of clinical diagnosis in 5 (4.7%) cases. Overall, diagnostic yield of this well-curated small panel was comparable to Western studies with larger gene panels. Moreover, this was achievable at a much lower cost, making it suitable for resource-constraint settings. In addition, high frequency (>10%) of cryptic pathogenic IBMFS gene variations in IAA cohort suggests routine incorporation of targeted next-generation sequencing screening in these cases.


Assuntos
Doenças da Medula Óssea , Adulto , Adolescente , Humanos , Criança , Doenças da Medula Óssea/diagnóstico , Doenças da Medula Óssea/genética , Síndrome Congênita de Insuficiência da Medula Óssea , Análise Custo-Benefício , Transtornos da Insuficiência da Medula Óssea , Sequenciamento de Nucleotídeos em Larga Escala , Células Germinativas
19.
Indian J Pathol Microbiol ; 65(1): 105-110, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35074973

RESUMO

INTRODUCTION: Optimal DNA and RNA quantity and purity is essential for downstream molecular biology experimentation and to avoid re-processing of sample. Despite availability of different kits and automated systems for nucleic acid isolation there is limited data on their performance evaluation, more so with pediatric blood samples, that are usually compromised in quantity. Hence, we evaluated the performance of automated QIAcube platform using pediatric blood samples in parallel with manual Qiagen extraction kits. MATERIALS AND METHODS: : A total of 500 samples were analyzed based on groups of PBMC and direct blood input. The isolated DNA and RNA were surveyed for quantity and quality tests by spectrophotometric and downstream analysis. RESULTS: : There was no significant difference in the DNA quantity (ng/ul) between manual and automated method based on similar sample input but quality (260/280) was significantly better with the QIAcube platform when direct blood and or PBMCs were used for extraction respectively (1.82 ± 004 Vs. 1.84.002; P-0.000008 and 1.859 ± 005 Vs. 1.843 ± 0.003; P-0.02). Moreover, the standard error mean was low for both quantity and quality in the QIAcube method suggesting uniformity. Comparison of quality assessment by spectrophotometer and qubit fluorimeter showed that QIAcube sheared DNA less (P- 0.038) as compared to manual method (P-0.013). Also, time taken to process the samples in QIAcube was 23% less than the kit-based method. CONCLUSION: Overall analysis of QIAcube platform suggests that it yields more better, uniform, and less-sheared quality of nucleic acid in a relatively less time as compared to manual extraction kits.


Assuntos
Automação Laboratorial/normas , Células Sanguíneas , DNA/isolamento & purificação , Leucócitos Mononucleares , Biologia Molecular/métodos , RNA/isolamento & purificação , Kit de Reagentes para Diagnóstico/normas , Automação Laboratorial/métodos , Criança , Pré-Escolar , DNA/normas , Humanos , Lactente , Biologia Molecular/instrumentação , Biologia Molecular/normas , RNA/normas
20.
Front Public Health ; 10: 873881, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35832276

RESUMO

During health emergencies such as the COVID-19 pandemic, healthcare workers face numerous ethical challenges while catering to the needs of patients in healthcare settings. Although the data recapitulating high-income countries ethics frameworks are available, the challenges faced by clinicians in resource-limited settings of low- and middle-income countries are not discussed widely due to a lack of baseline data or evidence. The Nepali healthcare system, which is chronically understaffed and underequipped, was severely affected by the COVID-19 pandemic in its capacity to manage health services and resources for needy patients, leading to ethical dilemmas and challenges during clinical practice. This study aimed to develop a standard guideline that would address syndemic ethical dilemmas during clinical care of COVID-19 patients who are unable to afford standard-of-care. A mixed method study was conducted between February and June of 2021 in 12 government designated COVID-19 treatment hospitals in central Nepal. The draft guideline was discussed among the key stakeholders in the pandemic response in Nepal. The major ethical dilemmas confronted by the study participants (50 healthcare professionals providing patient care at COVID-19 treatment hospitals) could be grouped into five major pillars of ethical clinical practice: rational allocation of medical resources, updated treatment protocols that guide clinical decisions, standard-of-care regardless of patient's economic status, effective communication among stakeholders for prompt patient care, and external factors such as political and bureaucratic interference affecting ethical practice. This living clinical ethics guideline, which has been developed based on the local evidence and case stories of frontline responders, is expected to inform the policymakers as well as the decision-makers positioned at the concerned government units. These ethics guidelines could be endorsed with revisions by the concerned regulatory authorities for the use during consequent waves of COVID-19 and other epidemics that may occur in the future. Other countries affected by the pandemic could conduct similar studies to explore ethical practices in the local clinical and public health context.


Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19 , COVID-19/epidemiologia , Ética Clínica , Medicina Baseada em Evidências , Serviços de Saúde , Humanos , Nepal , Pandemias , Guias de Prática Clínica como Assunto
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