Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 66
Filtrar
1.
Mod Pathol ; 32(2): 306-313, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30206410

RESUMO

At the histological level, tumor budding in colon cancer is the result of cells undergoing at least partial epithelial-to-mesenchymal transition. The microRNA 200 family is an important epigenetic driver of this process, mainly by downregulating zinc-finger E-box binding homeobox (ZEB) and transforming growth factor beta (TGF-ß) expression. We retrospectively explored the expression of the miR200 family, and ZEB1 and ZEB2, and their relationship with immune resistance mediated through PD-L1 overexpression. For this purpose, we analyzed a series of 125 colon cancer cases and took samples from two different tumor sites: the area of tumor budding at the invasive front and from the tumor center. We found significant ZEB overexpression and a reduction in miR200 in budding areas, a profile compatible with epithelial-to-mesenchymal transition. In multivariate analysis of the cases with localized disease, low miR200c expression in budding areas, but not at the tumor center, was an adverse tumor-specific survival factor (hazard ratio: 0.12; 95% confidence interval: 0.03-0.81; p = 0.02) independent of the clinical stage of the disease. PD-L1 was significantly overexpressed in the budding areas and its levels correlated with a mesenchymal transition profile. These results highlight the importance of including budding areas among the samples used for biomarker evaluation and provides relevant data on the influence of mesenchymal transition in the immune resistance mediated by PD-L1 overexpression.


Assuntos
Antígeno B7-H1/biossíntese , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Transição Epitelial-Mesenquimal/genética , MicroRNAs/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Colo/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
2.
Exp Dermatol ; 26(10): 896-903, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28266728

RESUMO

Sunlight exposure induces signalling pathways leading to the activation of melanin synthesis and tanning response. MicroRNAs (miRNAs) can regulate the expression of genes involved in pigmentation pathways by binding to the complementary sequence in their 3'untranslated regions (3'UTRs). Therefore, 3'UTR SNPs are predicted to modify the ability of miRNAs to target genes, resulting in differential gene expression. In this study, we investigated the role in pigmentation and sun-sensitivity traits, as well as in melanoma susceptibility, of 38 different 3'UTR SNPs from 38 pigmentation-related genes. A total of 869 individuals of Spanish origin (526 melanoma cases and 343 controls) were analysed. The association of genotypic data with pigmentation traits was analysed via logistic regression. Web-based tools for predicting the effect of genetic variants in microRNA-binding sites in 3'UTR gene regions were also used. Seven 3'UTR SNPs showed a potential implication in melanoma risk phenotypes. This association is especially noticeable for two of them, rs2325813 in the MLPH gene and rs752107 in the WNT3A gene. These two SNPs were predicted to disrupt a miRNA-binding site and to impact on miRNA-mRNA interaction. To our knowledge, this is the first time that these two 3'UTR SNPs have been associated with sun-sensitivity traits. We state the potential implication of these SNPs in human pigmentation and sensitivity to sunlight, possibly as a result of changes in the level of gene expression through the disruption of putative miRNA-binding sites.


Assuntos
Regiões 3' não Traduzidas/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Melanoma/genética , MicroRNAs/metabolismo , RNA Mensageiro/metabolismo , Neoplasias Cutâneas/genética , Pigmentação da Pele/genética , Proteína Wnt3A/genética , Sítios de Ligação , Estudos de Casos e Controles , Cor de Olho/genética , Frequência do Gene , Predisposição Genética para Doença , Cor de Cabelo/genética , Humanos , Lentigo/genética , MicroRNAs/genética , Fenótipo , Transtornos de Fotossensibilidade/genética , Polimorfismo de Nucleotídeo Único , Fatores de Proteção , RNA Mensageiro/genética , Fatores de Risco , Espanha , População Branca/genética
3.
Breast Cancer Res Treat ; 160(1): 69-77, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27628192

RESUMO

BACKGROUND: There is increasing interest in the molecular profiling of tumour tissues in order to investigate alternative breast cancer (BC) therapies. However, the impact of genomic screening for druggable mutations with targeted gene panel sequencing (TGPS) in routine practice remains controversial. METHODS: This is a retrospective analysis of data from a genomic screening programme at our institution, in which we performed simplified TGPS for mutations in PIK3CA, AKT1, KRAS, NRAS, and BRAF in order to select patients for targeted therapy clinical trials. The genomes of archived samples of primary (PT) and/or metastatic (MT) tumours from advanced BC patients were analysed with MassARRAY technology (Sequenom MassARRAY, OncoCarta v1.0). The level of PTEN expression was assessed by immunohistochemistry. The primary endpoint was to identify the proportion of BC patients with PI3 K and MAPK alterations who were included in clinical trials using targeted therapies against these pathways. RESULTS: Two hundred and fifteen metastatic BC patients (65 PT and 168 MT) were included. Fifty-two patients (24.19 %) were enrolled in tailored clinical trials, of whom 29 (55.77, 13.49 % of all patients screened) harboured mutations targeted by the study drug. Moreover, 12 wild-type patients out of the 215 (5.58 %) were included in the clinical trials for which mutation analysis was an inclusion criteria. All the patients received drugs targeting the PI3K-AKT pathway and only two were given combinations directed against the PI3K and MAPK pathways. PI3KCA mutations were present in 33.7 % (61/181) of the patients, 45.83 % in PTs and 29.32 % in MTs. AKT1 mutations were detected in 5.48 % (8/146) of patients and PTEN loss in 34.67 % (52/150). KRAS, NRAS, and BRAF mutations were present in 12.06, 5.67, and 3.18 % of patients, respectively. CONCLUSIONS: Genomic screening with a simplified TGPS is feasible, and was used to identify 13.49 % of patients who were included in clinical trials using targeted therapy against the mutations they harboured; PI3KCA mutations were the most frequent aberration in our series.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/mortalidade , Mutação , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas ras/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Substituição de Aminoácidos , Biomarcadores Tumorais , Neoplasias da Mama/patologia , Análise Mutacional de DNA , Feminino , Frequência do Gene , Genômica , Humanos , Pessoa de Meia-Idade , Gradação de Tumores , Metástase Neoplásica , Estadiamento de Neoplasias
4.
J Cell Biochem ; 116(9): 2061-73, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25802200

RESUMO

UNLABELLED: Chemotherapy treatment is the standard in triple negative breast cancers, a cancer subgroup which lacks a specific target. The mechanisms leading to the response, as well as any markers that allow the differentiation between responder and non-responder groups prior to treatment are unknown. In parallel, miRNAs can act as oncogenes or tumor suppressors and there is evidence of their involvement in promoting resistance to anticancer drugs. Therefore we hypothesized that changes in miRNA expression after doxorubicin treatment may also be relevant in treatment response. OBJECTIVE: To study miRNAs that are differentially expressed in response to doxorubicin treatment. METHODS: One luminal-A and two triple negative, breast cancer cell lines were exposed to doxorubicin. Microarray analysis was performed to identify the common and differentially modified miRNAs. Genes and pathways that are theoretically regulated by these miRNAs were analyzed. RESULTS: Thirteen miRNAs common to all three lines were modified, in addition to 25 that were specific to triple negative cell lines, and 69 that changed only in the luminal-A cell line. This altered expression pattern seemed to be more strongly related to the breast cancer subgroup than to the treatment. The analysis of target genes revealed that cancer related pathways were the most affected by these miRNAs, moreover many of them had been previously related to chemotherapy resistance; thus suggesting follow-up studies. Additionally, through functional assays, we showed that miR-548c-3p is implicated in doxorubicin-treated MCF-7 cell viability, suggesting a role for this miRNA in resistance.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Neoplasias da Mama/genética , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos , MicroRNAs/genética , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular , Feminino , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Redes Reguladoras de Genes/efeitos dos fármacos , Humanos , Células MCF-7 , MicroRNAs/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos/métodos
5.
Int J Cancer ; 136(9): 2109-19, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25303718

RESUMO

Multifactorial predisposition to melanoma includes genes involved in pigmentation, immunity and DNA repair. Nonetheless, missing heritability in melanoma is still important. We studied the role of 335 candidate SNPs in melanoma susceptibility by using a dedicated chip and investigating 110 genes involved in different pathways. A discovery set was comprised of 1069 melanoma patients and 925 controls from France. Data were replicated using validation phases II (1085 cases and 801 controls from Spain) and III (1808 cases and 1894 controls from Germany and a second set of Spanish samples). In addition, an exome sequencing study was performed in three high-risk French melanoma families. Nineteen SNPs in 17 genes were initially associated with melanoma in the French population. Six SNPs were replicated in phase II, including two new SNPs in the WNT3 (rs199524) and VPS41 (rs11773094) genes. The role of VPS41 and WNT3 was confirmed in a meta-analysis (3940 melanoma cases and 3620 controls) with two-side p values of 0.002, (OR = 0.86) and 4.07 × 10(-10) (OR = 0.80), respectively. Exome sequencing revealed a non-synonymous VPS41 variant in one family that was shown to be strongly associated with familial melanoma (OR = 4.46, p = 0.001) in an independent sample of 178 melanoma families. WNT3 belongs to WNT pathway known to play a crucial role in melanoma, whereas VPS41 regulates vesicular trafficking and is thought to play a role in pigmentation. Our work identified two new pathways involved in melanoma predisposition. These results may be useful in the future for identifying individuals highly predisposed to melanoma.


Assuntos
Predisposição Genética para Doença/genética , Melanoma/genética , Transdução de Sinais/genética , Proteína Wnt3/genética , Estudos de Casos e Controles , Feminino , Frequência do Gene/genética , Genótipo , Humanos , Masculino , Pigmentação/genética , Polimorfismo de Nucleotídeo Único/genética , Fatores de Risco , Neoplasias Cutâneas/genética , Proteínas de Transporte Vesicular/genética
6.
Int J Cancer ; 136(3): 618-31, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24917043

RESUMO

The MC1R gene is a key regulator of skin pigmentation. We aimed to evaluate the association between MC1R variants and the risk of sporadic cutaneous melanoma (CM) within the M-SKIP project, an international pooled-analysis on MC1R, skin cancer and phenotypic characteristics. Data included 5,160 cases and 12,119 controls from 17 studies. We calculated a summary odds ratio (SOR) for the association of each of the nine most studied MC1R variants and of variants combined with CM by using random-effects models. Stratified analysis by phenotypic characteristics were also performed. Melanoma risk increased with presence of any of the main MC1R variants: the SOR for each variant ranged from 1.47 (95%CI: 1.17-1.84) for V60L to 2.74 (1.53-4.89) for D84E. Carriers of any MC1R variant had a 66% higher risk of developing melanoma compared with wild-type subjects (SOR; 95%CI: 1.66; 1.41-1.96) and the risk attributable to MC1R variants was 28%. When taking into account phenotypic characteristics, we found that MC1R-associated melanoma risk increased only for darker-pigmented Caucasians: SOR (95%CI) was 3.14 (2.06-4.80) for subjects with no freckles, no red hair and skin Type III/IV. Our study documents the important role of all the main MC1R variants in sporadic CM and suggests that they have a direct effect on melanoma risk, independently on the phenotypic characteristics of carriers. This is of particular importance for assessing preventive strategies, which may be directed to darker-pigmented Caucasians with MC1R variants as well as to lightly pigmented, fair-skinned subjects.


Assuntos
Predisposição Genética para Doença , Melanoma/genética , Receptor Tipo 1 de Melanocortina/genética , Neoplasias Cutâneas/genética , Humanos , Melanoma/etiologia , Pessoa de Meia-Idade , Fenótipo , Risco , Neoplasias Cutâneas/etiologia , Pigmentação da Pele , População Branca
7.
IUBMB Life ; 67(4): 227-38, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25904072

RESUMO

Early pregnancy is associated with a reduction in a woman's lifetime risk for breast cancer. However, different studies have demonstrated an increase in breast cancer risk in the years immediately following pregnancy. Early and long-term risk is even higher if the mother age is above 35 years at the time of first parity. The proinflammatory microenvironment within the mammary gland after pregnancy renders an "ideal niche" for oncogenic events. Signaling pathways involved in programmed cell death and tissue remodeling during involution are also activated in breast cancer. Herein, the major signaling pathways involved in mammary gland involution, signal transducer and activator of transcription (STAT3), nuclear factor-kappa B (NF-κB), transforming growth factor beta (TGFß), and retinoid acid receptors (RARs)/retinoid X receptors (RXRs), are reviewed as part of the complex network of signaling pathways that crosstalk in a contextual-dependent manner. These factors, also involved in breast cancer development, are important regulatory nodes for signaling amplification after weaning. Indeed, during involution, p65/p300 target genes such as MMP9, Capn1, and Capn2 are upregulated. Elevated expression and activities of these proteases in breast cancer have been extensively documented. The role of these proteases during mammary gland involution is further discussed. MMPs, calpains, and cathepsins exert their effect by modification of the extracellular matrix and intracellular proteins. Calpains, activated in the mammary gland during involution, cleave several proteins located in cell membrane, lysosomes, mitochondria, and nuclei favoring cell death. Besides, during this period, Capn1 is most probably involved in the modulation of preadipocyte differentiation through chromatin remodeling. Calpains can be implicated in cell anchoring loss, providing a proper microenvironment for tumor growth. A better understanding of the role of any of these proteases in tumorigenesis may yield novel therapeutic targets or prognostic markers for breast cancer.


Assuntos
Neoplasias da Mama/patologia , Lactação , Glândulas Mamárias Humanas/fisiopatologia , Feminino , Humanos , NF-kappa B/metabolismo , Peptídeo Hidrolases/metabolismo , Gravidez , Fatores de Risco , Transdução de Sinais , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta/metabolismo
9.
Mol Biol Evol ; 30(12): 2654-65, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24045876

RESUMO

In humans, the geographical apportionment of the coding diversity of the pigmentary locus melanocortin-1 receptor (MC1R) is, unusually, higher in Eurasians than in Africans. This atypical observation has been interpreted as the result of purifying selection due to functional constraint on MC1R in high UV-B radiation environments. By analyzing 3,142 human MC1R alleles from different regions of Spain in the context of additional haplotypic information from the 1000 Genomes (1000G) Project data, we show that purifying selection is also strong in southern Europe, but not so in northern Europe. Furthermore, we show that purifying and positive selection act simultaneously on MC1R. Thus, at least in Spain, regions at opposite ends of the incident UV-B radiation distribution show significantly different frequencies for the melanoma-risk allele V60L (a mutation also associated to red hair and fair skin and even blonde hair), with higher frequency of V60L at those regions of lower incident UV-B radiation. Besides, using the 1000G south European data, we show that the V60L haplogroup is also characterized by an extended haplotype homozygosity (EHH) pattern indicative of positive selection. We, thus, provide evidence for an adaptive value of human skin depigmentation in Europe and illustrate how an adaptive process can simultaneously help to maintain a disease-risk allele. In addition, our data support the hypothesis proposed by Jablonski and Chaplin (Human skin pigmentation as an adaptation to UVB radiation. Proc Natl Acad Sci U S A. 2010;107:8962-8968), which posits that habitation of middle latitudes involved the evolution of partially depigmented phenotypes that are still capable of suitable tanning.


Assuntos
Melanoma/genética , Receptor Tipo 1 de Melanocortina/genética , Seleção Genética , Pigmentação da Pele/genética , População Branca/genética , Alelos , Evolução Molecular , Predisposição Genética para Doença , Variação Genética , Haplótipos , Homozigoto , Humanos , Mutação , Fenótipo , Pigmentação da Pele/efeitos da radiação , Espanha , Raios Ultravioleta/efeitos adversos
10.
BMC Cancer ; 14: 529, 2014 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-25047087

RESUMO

BACKGROUND: Breast cancer is rarely diagnosed in very young women (35 years old or younger), and it often presents with distinct clinical-pathological features related to a more aggressive phenotype and worse prognosis when diagnosed at this early age. A pending question is whether breast cancer in very young women arises from the deregulation of different underlying mechanisms, something that will make this disease an entity differentiated from breast cancer diagnosed in older patients. METHODS: We performed a comprehensive study of miRNA expression using miRNA Affymetrix2.0 array on paraffin-embedded tumour tissue of 42 breast cancer patients 35 years old or younger, 17 patients between 45 and 65 years old and 29 older than 65 years. Data were statistically analyzed by t-test and a hierarchical clustering via average linkage method was conducted. Results were validated by qRT-PCR. Putative targeted pathways were obtained using DIANA miRPath online software. RESULTS: The results show a differential and unique miRNA expression profile of 121 miRNAs (p-value <0.05), 96 of those with a FDR-value <0.05. Hierarchical clustering grouped the samples according to their age, but not by subtype nor by tumour characteristics. We were able to validate by qRT-PCR differences in the expression of 6 miRNAs: miR-1228*, miR-3196, miR-1275, miR-92b, miR-139 and miR-1207. Moreover, all of the miRNAs maintained the expression trend. The validated miRNAs pointed out pathways related to cell motility, invasion and proliferation. CONCLUSIONS: The study suggests that breast cancer in very young women appears as a distinct molecular signature. To our knowledge, this is the first time that a validated microRNA profile, distinctive to breast cancer in very young women, has been presented. The miRNA signature may be relevant to open an important field of research in order to elucidate the underlying mechanism in this particular disease, which in a more clinical setting, could potentially help to identify therapeutic targets in this particular set of patients.


Assuntos
Neoplasias da Mama/genética , Perfilação da Expressão Gênica/métodos , MicroRNAs/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Adulto , Fatores Etários , Idoso , Neoplasias da Mama/patologia , Análise por Conglomerados , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Adulto Jovem
11.
Nat Genet ; 37(4): 423-8, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15735645

RESUMO

Atrial septal defect is one of the most common forms of congenital heart malformation. We identified a new locus linked with atrial septal defect on chromosome 14q12 in a large family with dominantly inherited atrial septal defect. The underlying mutation is a missense substitution, I820N, in alpha-myosin heavy chain (MYH6), a structural protein expressed at high levels in the developing atria, which affects the binding of the heavy chain to its regulatory light chain. The cardiac transcription factor TBX5 strongly regulates expression of MYH6, but mutant forms of TBX5, which cause Holt-Oram syndrome, do not. Morpholino knock-down of expression of the chick MYH6 homolog eliminates the formation of the atrial septum without overtly affecting atrial chamber formation. These data provide evidence for a link between a transcription factor, a structural protein and congenital heart disease.


Assuntos
Miosinas Cardíacas/genética , Comunicação Interatrial/genética , Mutação de Sentido Incorreto , Cadeias Pesadas de Miosina/genética , Proteínas com Domínio T/genética , Adulto , Substituição de Aminoácidos , Animais , Miosinas Cardíacas/metabolismo , Embrião de Galinha , Criança , Pré-Escolar , Feminino , Ligação Genética , Comunicação Interatrial/embriologia , Humanos , Recém-Nascido , Masculino , Dados de Sequência Molecular , Cadeias Pesadas de Miosina/metabolismo , Linhagem , Proteínas com Domínio T/química
12.
Neuro Oncol ; 26(3): 488-502, 2024 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-37882631

RESUMO

BACKGROUND: There is an urgent need to better understand the mechanisms associated with the development, progression, and onset of recurrence after initial surgery in glioblastoma (GBM). The use of integrative phenotype-focused -omics technologies such as proteomics and lipidomics provides an unbiased approach to explore the molecular evolution of the tumor and its associated environment. METHODS: We assembled a cohort of patient-matched initial (iGBM) and recurrent (rGBM) specimens of resected GBM. Proteome and metabolome composition were determined by mass spectrometry-based techniques. We performed neutrophil-GBM cell coculture experiments to evaluate the behavior of rGBM-enriched proteins in the tumor microenvironment. ELISA-based quantitation of candidate proteins was performed to test the association of their plasma concentrations in iGBM with the onset of recurrence. RESULTS: Proteomic profiles reflect increased immune cell infiltration and extracellular matrix reorganization in rGBM. ASAH1, SYMN, and GPNMB were highly enriched proteins in rGBM. Lipidomics indicates the downregulation of ceramides in rGBM. Cell analyses suggest a role for ASAH1 in neutrophils and its localization in extracellular traps. Plasma concentrations of ASAH1 and SYNM show an association with time to recurrence. CONCLUSIONS: We describe the potential importance of ASAH1 in tumor progression and development of rGBM via metabolic rearrangement and showcase the feedback from the tumor microenvironment to plasma proteome profiles. We report the potential of ASAH1 and SYNM as plasma markers of rGBM progression. The published datasets can be considered as a resource for further functional and biomarker studies involving additional -omics technologies.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/patologia , Metabolismo dos Lipídeos , Proteoma/metabolismo , Proteômica , Ceramidas/metabolismo , Neoplasias Encefálicas/patologia , Microambiente Tumoral , Glicoproteínas de Membrana
13.
BMC Cancer ; 13: 160, 2013 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-23537197

RESUMO

BACKGROUND: Few high penetrance genes are known in Malignant Melanoma (MM), however, the involvement of low-penetrance genes such as MC1R, OCA2, ASIP, SLC45A2 and TYR has been observed. Lately, genome-wide association studies (GWAS) have been the ideal strategy to identify new common, low-penetrance susceptibility loci. In this case-control study, we try to validate in our population nine melanoma associated markers selected from published GWAS in melanoma predisposition. METHODS: We genotyped the 9 markers corresponding to 8 genes (PARP1, MX2, ATM, CCND1, NADSYN1, CASP8, IRF4 and CYP2R1) in 566 cases and 347 controls from a Spanish population using KASPar probes. Genotypes were analyzed by logistic regression and adjusted by phenotypic characteristics. RESULTS: We confirm the protective role in MM of the rs3219090 located on the PARP1 gene (p-value 0.027). Additionally, this SNP was also associated with eye color (p-value 0.002). A second polymorphism, rs12203592, located on the IRF4 gene was associated with protection to develop MM for the dominant model (p-value 0.037). We have also observed an association of this SNP with both lentigines (p-value 0.014) and light eye color (p-value 3.76 × 10(-4)). Furthermore, we detected a novel association with rs1485993, located on the CCND1 gene, and dark eye color (p-value 4.96 × 10(-4)). Finally, rs1801516, located on the ATM gene, showed a trend towards a protective role in MM similar to the one firstly described in a GWAS study. CONCLUSIONS: To our knowledge, this is the first time that these SNPs have been associated with MM in a Spanish population. We confirmed the proposed role of rs3219090, located on the PARP1 gene, and rs12203592, located on the IRF4 gene, as protective to MM along the same lines as have previous genome-wide associated works. Finally, we have seen associations between IRF4, PARP1, and CCND1 and phenotypic characteristics, confirming previous results for the IRF4 gene and presenting novel data for the last two, suggesting that pigmentation characteristics correlated with eye color are potential mediators between PARP1 and MM protection.


Assuntos
Predisposição Genética para Doença/genética , Fatores Reguladores de Interferon/genética , Melanoma/genética , Poli(ADP-Ribose) Polimerases/genética , Estudos de Casos e Controles , Feminino , Variação Genética , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Poli(ADP-Ribose) Polimerase-1 , Polimorfismo de Nucleotídeo Único , Espanha
14.
Nature ; 450(7171): 887-92, 2007 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-18004301

RESUMO

The major histocompatibility complex (MHC) on chromosome 6 is associated with susceptibility to more common diseases than any other region of the human genome, including almost all disorders classified as autoimmune. In type 1 diabetes the major genetic susceptibility determinants have been mapped to the MHC class II genes HLA-DQB1 and HLA-DRB1 (refs 1-3), but these genes cannot completely explain the association between type 1 diabetes and the MHC region. Owing to the region's extreme gene density, the multiplicity of disease-associated alleles, strong associations between alleles, limited genotyping capability, and inadequate statistical approaches and sample sizes, which, and how many, loci within the MHC determine susceptibility remains unclear. Here, in several large type 1 diabetes data sets, we analyse a combined total of 1,729 polymorphisms, and apply statistical methods-recursive partitioning and regression-to pinpoint disease susceptibility to the MHC class I genes HLA-B and HLA-A (risk ratios >1.5; P(combined) = 2.01 x 10(-19) and 2.35 x 10(-13), respectively) in addition to the established associations of the MHC class II genes. Other loci with smaller and/or rarer effects might also be involved, but to find these, future searches must take into account both the HLA class II and class I genes and use even larger samples. Taken together with previous studies, we conclude that MHC-class-I-mediated events, principally involving HLA-B*39, contribute to the aetiology of type 1 diabetes.


Assuntos
Diabetes Mellitus Tipo 1/genética , Genes MHC Classe I/genética , Predisposição Genética para Doença/genética , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Alelos , Estudos de Casos e Controles , Bases de Dados Genéticas , Frequência do Gene , Genes MHC da Classe II/genética , Genótipo , Antígenos HLA-DQ/genética , Cadeias beta de HLA-DQ , Antígenos HLA-DR/genética , Cadeias HLA-DRB1 , Humanos , Polimorfismo de Nucleotídeo Único/genética , Tamanho da Amostra , População Branca/genética
15.
Insights Imaging ; 14(1): 11, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36645542

RESUMO

The use of artificial intelligence (AI) with medical images to solve clinical problems is becoming increasingly common, and the development of new AI solutions is leading to more studies and publications using this computational technology. As a novel research area, the use of common standards to aid AI developers and reviewers as quality control criteria will improve the peer review process. Although some guidelines do exist, their heterogeneity and extension advocate that more explicit and simple schemes should be applied on the publication practice. Based on a review of existing AI guidelines, a proposal which collects, unifies, and simplifies the most relevant criteria was developed. The MAIC-10 (Must AI Criteria-10) checklist with 10 items was implemented as a guide to design studies and evaluate publications related to AI in the field of medical imaging. Articles published in Insights into Imaging in 2021 were selected to calculate their corresponding MAIC-10 quality score. The mean score was found to be 5.6 ± 1.6, with critical items present in most articles, such as "Clinical need", "Data annotation", "Robustness", and "Transparency" present in more than 80% of papers, while improvements in other areas were identified. MAIC-10 was also observed to achieve the highest intra-observer reproducibility when compared to other existing checklists, with an overall reduction in terms of checklist length and complexity. In summary, MAIC-10 represents a short and simple quality assessment tool which is objective, robust and widely applicable to AI studies in medical imaging.

16.
BMC Med Res Methodol ; 12: 116, 2012 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-22862891

RESUMO

BACKGROUND: For complex diseases like cancer, pooled-analysis of individual data represents a powerful tool to investigate the joint contribution of genetic, phenotypic and environmental factors to the development of a disease. Pooled-analysis of epidemiological studies has many advantages over meta-analysis, and preliminary results may be obtained faster and with lower costs than with prospective consortia. DESIGN AND METHODS: Based on our experience with the study design of the Melanocortin-1 receptor (MC1R) gene, SKin cancer and Phenotypic characteristics (M-SKIP) project, we describe the most important steps in planning and conducting a pooled-analysis of genetic epidemiological studies. We then present the statistical analysis plan that we are going to apply, giving particular attention to methods of analysis recently proposed to account for between-study heterogeneity and to explore the joint contribution of genetic, phenotypic and environmental factors in the development of a disease. Within the M-SKIP project, data on 10,959 skin cancer cases and 14,785 controls from 31 international investigators were checked for quality and recoded for standardization. We first proposed to fit the aggregated data with random-effects logistic regression models. However, for the M-SKIP project, a two-stage analysis will be preferred to overcome the problem regarding the availability of different study covariates. The joint contribution of MC1R variants and phenotypic characteristics to skin cancer development will be studied via logic regression modeling. DISCUSSION: Methodological guidelines to correctly design and conduct pooled-analyses are needed to facilitate application of such methods, thus providing a better summary of the actual findings on specific fields.


Assuntos
Projetos de Pesquisa Epidemiológica , Predisposição Genética para Doença , Receptor Tipo 1 de Melanocortina , Neoplasias Cutâneas/genética , Luz Solar/efeitos adversos , Adulto , Estudos de Casos e Controles , Coleta de Dados/normas , Interpretação Estatística de Dados , Feminino , Hospitalização , Humanos , Modelos Logísticos , Masculino , Metanálise como Assunto , Fenótipo , Neoplasias Cutâneas/fisiopatologia , Neoplasias Cutâneas/secundário , Fumar
17.
Insights Imaging ; 13(1): 89, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35536446

RESUMO

To achieve clinical impact in daily oncological practice, emerging AI-based cancer imaging research needs to have clearly defined medical focus, AI methods, and outcomes to be estimated. AI-supported cancer imaging should predict major relevant clinical endpoints, aiming to extract associations and draw inferences in a fair, robust, and trustworthy way. AI-assisted solutions as medical devices, developed using multicenter heterogeneous datasets, should be targeted to have an impact on the clinical care pathway. When designing an AI-based research study in oncologic imaging, ensuring clinical impact in AI solutions requires careful consideration of key aspects, including target population selection, sample size definition, standards, and common data elements utilization, balanced dataset splitting, appropriate validation methodology, adequate ground truth, and careful selection of clinical endpoints. Endpoints may be pathology hallmarks, disease behavior, treatment response, or patient prognosis. Ensuring ethical, safety, and privacy considerations are also mandatory before clinical validation is performed. The Artificial Intelligence for Health Imaging (AI4HI) Clinical Working Group has discussed and present in this paper some indicative Machine Learning (ML) enabled decision-support solutions currently under research in the AI4HI projects, as well as the main considerations and requirements that AI solutions should have from a clinical perspective, which can be adopted into clinical practice. If effectively designed, implemented, and validated, cancer imaging AI-supported tools will have the potential to revolutionize the field of precision medicine in oncology.

18.
J Inorg Biochem ; 232: 111812, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35421769

RESUMO

Metal complexes based on purine nucleobases can be a very useful tool in the diagnosis and treatment of some diseases as well as in other biomedical applications. We have prepared and characterized a novel dinuclear ruthenium(III) complex based on the nucleobase adenine of formula [{Ru(µ-Cl)(µ-Hade)}2Cl4]Cl2·2H2O (1) [Hade = protonated adenine]. Complex 1 was characterized through Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy and energy dispersive X-ray analysis (SEM-EDX), magnetometer (SQUID) and cyclic voltammetry (CV) techniques. The crystal structure of 1 was determined by single-crystal X-ray diffraction. 1 crystallizes in the monoclinic system with space group P21/n. Each ruthenium(III) ion is six-coordinate and bonded to four Cl atoms [the average value of the RuIII-Cl bonds lengths is ca. 2.329(1) Å] and two N atoms (N3 and N9) from two adenine molecules, the N1 atom being protonated in both of them. The anticancer activity was evaluated through cell viability assays performed on a colon cancer (HCT116) and a gastric cancer cell lines (AGS), 1 showing an incipient anticancer effect on the AGS cell line at the highest concentration used in the study.


Assuntos
Compostos Organometálicos , Rutênio , Adenina/química , Cristalografia por Raios X , Modelos Moleculares , Compostos Organometálicos/química , Rutênio/química , Espectroscopia de Infravermelho com Transformada de Fourier
19.
Cancers (Basel) ; 15(1)2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36612065

RESUMO

Ruthenium compounds have demonstrated promising activity in different cancer types, overcoming several limitations of platinum-based drugs, yet their global structure-activity is still under debate. We analyzed the activity of Runat-BI, a racemic Ru(III) compound, and of one of its isomers in eight tumor cell lines of breast, colon and gastric cancer as well as in a non-tumoral control. Runat-BI was prepared with 2,2'-biimidazole and dissolved in polyethylene glycol. We performed assays of time- and dose-dependent viability, migration, proliferation, and expression of pro- and antiapoptotic genes. Moreover, we studied the growth rate and cell doubling time to correlate it with the apoptotic effect of Runat-BI. As a racemic mixture, Runat-BI caused a significant reduction in the viability and migration of three cancer cell lines from colon, gastric and breast cancer, all of which displayed fast proliferation rates. This compound also demonstrated selectivity between tumor and non-tumor lines and increased proapoptotic gene expression. However, the isolated isomer did not show any effect. Racemic Runat-BI is a potential drug candidate for treatment of highly aggressive tumors. Further studies should be addressed at evaluating the role of the other isomer, for a more precise understanding of its antitumoral potential and mechanism of action.

20.
PLoS Genet ; 4(4): e1000054, 2008 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-18437204

RESUMO

A three-stage genome-wide association study recently identified single nucleotide polymorphisms (SNPs) in five loci (fibroblast growth receptor 2 (FGFR2), trinucleotide repeat containing 9 (TNRC9), mitogen-activated protein kinase 3 K1 (MAP3K1), 8q24, and lymphocyte-specific protein 1 (LSP1)) associated with breast cancer risk. We investigated whether the associations between these SNPs and breast cancer risk varied by clinically important tumor characteristics in up to 23,039 invasive breast cancer cases and 26,273 controls from 20 studies. We also evaluated their influence on overall survival in 13,527 cases from 13 studies. All participants were of European or Asian origin. rs2981582 in FGFR2 was more strongly related to ER-positive (per-allele OR (95%CI) = 1.31 (1.27-1.36)) than ER-negative (1.08 (1.03-1.14)) disease (P for heterogeneity = 10(-13)). This SNP was also more strongly related to PR-positive, low grade and node positive tumors (P = 10(-5), 10(-8), 0.013, respectively). The association for rs13281615 in 8q24 was stronger for ER-positive, PR-positive, and low grade tumors (P = 0.001, 0.011 and 10(-4), respectively). The differences in the associations between SNPs in FGFR2 and 8q24 and risk by ER and grade remained significant after permutation adjustment for multiple comparisons and after adjustment for other tumor characteristics. Three SNPs (rs2981582, rs3803662, and rs889312) showed weak but significant associations with ER-negative disease, the strongest association being for rs3803662 in TNRC9 (1.14 (1.09-1.21)). rs13281615 in 8q24 was associated with an improvement in survival after diagnosis (per-allele HR = 0.90 (0.83-0.97). The association was attenuated and non-significant after adjusting for known prognostic factors. Our findings show that common genetic variants influence the pathological subtype of breast cancer and provide further support for the hypothesis that ER-positive and ER-negative disease are biologically distinct. Understanding the etiologic heterogeneity of breast cancer may ultimately result in improvements in prevention, early detection, and treatment.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Proteínas Reguladoras de Apoptose , Estudos de Casos e Controles , Cromossomos Humanos Par 8/genética , Feminino , Proteínas de Grupo de Alta Mobilidade , Humanos , Desequilíbrio de Ligação , MAP Quinase Quinase Quinase 1/genética , Proteínas dos Microfilamentos/genética , Pessoa de Meia-Idade , Razão de Chances , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Receptores de Progesterona/genética , Transativadores , Repetições de Trinucleotídeos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA