RESUMO
PURPOSE: Adoptees are a population that could benefit from genetic testing to fill gaps in family health history (FHH). Elective genomic testing (EGT) provides adoptees with clinical genetic testing options to learn about genetic health risks in the absence of FHH. We assessed adoptees' interests in, motivations for and perceived utility of EGT. METHODS: Adult adoptees and non-adoptees completed an anonymous, online survey regarding their interest and motivations for EGT, perceived utility of potential results and willingness to pay for EGT. A validated measure of social identity was included to measure the effects of social identity on testing interest. RESULTS: There were 112 adoptees and 229 non-adoptees included in the study. Adoptees reported greater interest in EGT (OR 5.0, 95% CI 2.2 to 11.3) than non-adoptees. They were motivated by curiosity and a desire to learn information about risks to children and grandchildren more than non-adoptees. Adoptees with higher education and non-adoptees with higher incomes were significantly more likely to spend more on EGT. Adoptees with higher incomes and non-adoptees with higher education were not significantly more likely to spend more. Social identity was a significant mediator between adoption and testing motivation. CONCLUSION: Understanding adoptees' unique motivations and interests in EGT will allow healthcare providers to better address the informational needs and desires of this population. Social identity provides a foundation for recognising adoptees' universal experiences that influence motivations for genetic testing.
Assuntos
Adoção , Testes Genéticos , Adoção/psicologia , Adulto , Escolaridade , Feminino , Testes Genéticos/economia , Humanos , Masculino , Pessoa de Meia-Idade , Motivação , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Identificação Social , Inquéritos e QuestionáriosRESUMO
BACKGROUND: Despite the benefits of genetic counseling and testing, uptake of cancer genetic services is generally low and Black/African American (Black) women are substantially less likely to receive genetic services than non-Hispanic White women. Our team developed a culturally sensitive, narrative decision aid video to promote uptake of genetic counseling among Black women at risk for a hereditary breast cancer syndrome that can be incorporated in conjunction with population-based cancer risk assessment in a clinical setting. We report here a pilot study to demonstrate changes in intention to access genetic counseling and intervention satisfaction. METHODS: Black women who were personally unaffected by breast cancer and were recommended for genetic counseling based on family history screening in a mammography center were recruited at the time of the mammogram. A prospective, pre-post survey study design, guided by theoretical constructs, was used to evaluate baseline and immediate post-intervention psychosocial factors, including intention to participate in genetic counseling and intervention satisfaction. RESULTS: Pilot recruitment goals were met (n = 30). Pre-intervention, 50% of participants indicated that they were extremely likely to make a genetic counseling appointment, compared with 70% post-intervention (p = 0.05). After watching the intervention, 50% of participants indicated that the video changed their mind regarding genetic counseling. CONCLUSIONS: This study demonstrated cultural satisfaction with a decision aid intervention designed to motivate Black women with hereditary breast cancer risk to attend a genetic counseling appointment. Our study showed that intention may be a specific and key construct to target in interventions designed to support decision-making about genetic services. Study results informed the design of a subsequent large scale, randomized implementation study. TRIAL REGISTRATION: Trial registration: Clinicaltrials.gov NCT04082117 . Registered September 9, 2019. Retrospectively registered.
Assuntos
Neoplasias da Mama , Aconselhamento Genético , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Neoplasias da Mama/prevenção & controle , Feminino , Aconselhamento Genético/psicologia , Testes Genéticos , Humanos , Projetos Piloto , Estudos ProspectivosRESUMO
BACKGROUND: African American women with hereditary breast cancer risk are less likely to undergo genetic counseling and testing compared with non-Hispanic White women. Inequities in the use of precision cancer care are likely to exacerbate racial disparities in cancer outcomes. A culturally sensitive multimedia narrative intervention was developed to motivate African American women at risk for hereditary breast cancer to engage in genetic counseling. METHODS: Development of the intervention was grounded in the Integrative Model of Behavioral Prediction using a phenomenological, deductive approach and employed multiple qualitative methods for data collection, including 1-on-1 interviews and story circles with members of the target audience to identify salient themes and lived experiences. Focus group testing was then conducted with members of the group of focus, primary care providers, and community stakeholders. RESULTS: Six themes that mapped to the theoretical model were identified. Lived experiences were abstracted from story circle data to create a narrative storyline. Educational content and motivational messaging derived from the 6 themes were embedded into the script. Focus group testing with stakeholder groups was used to refine the intervention. Testing of the final multimedia narrative with focus groups indicated that the intervention was culturally sensitive and authentic, and the messaging was effective. CONCLUSIONS: Multiple qualitative data collection methods and a robust theoretical framework of health behavior were key elements for this study to develop a culturally sensitive, narrative intervention that reflects lived experiences and motivates underserved African American women with hereditary breast cancer risk to engage in genetic counseling. This strategy can be applied to mitigate racial inequities in the use of other genomic approaches for personalizing cancer care.
Assuntos
Negro ou Afro-Americano , Neoplasias da Mama , Negro ou Afro-Americano/psicologia , Neoplasias da Mama/genética , Neoplasias da Mama/prevenção & controle , Neoplasias da Mama/psicologia , Feminino , Grupos Focais , Aconselhamento Genético , HumanosRESUMO
Pediatric brain tumor survivorship populations have not been typically offered genetic services as part of routine care. Genetic services can be defined as family history collection, genetic risk assessment for a patient and family members, and coordination of genetic testing. Prior research has focused on the integration of genetic services in the general pediatric oncology survivorship population and found a need for these services to be implemented. Gathering a family history and providing a genetic risk assessment have previously been determined to be an integral step in determining if an individual's cancer was due to a hereditary predisposition. The purpose of this study was to examine parental attitudes regarding the need for genetic services in their child's pediatric brain tumor survivorship clinic. Twelve semi-structured interviews were conducted with parents participating in the Brain STAR (Survivors Taking Action and Responsibility) program at Ann and Robert H. Lurie Children's Hospital of Chicago. A grounded theory approach was used to code and analyze the results thematically. Five key themes were identified: participants' perceived benefits and barriers regarding receiving genetic services, desirable time for implementation of these services, relevance of family history, and their thoughts regarding reproductive risk. These results provide insight for genetics professionals regarding the need for genetic services in this population, and how to best implement them.
Assuntos
Neoplasias Encefálicas , Sobrevivência , Atitude , Neoplasias Encefálicas/genética , Criança , Serviços em Genética , Humanos , PaisRESUMO
Early identification of those with BRCA-related Hereditary Breast and Ovarian Cancer Syndrome (HBOC) and Lynch syndrome has the potential for early cancer detection and/or prevention; as such, these conditions are considered Tier 1 genetic conditions by the U.S. Center for Disease Control and Prevention. Given the decreasing cost of genetic testing, population-based screening (PBS) for such conditions may be the next step toward cancer prevention. This study aimed to understand genetic counselors' perspectives toward offering PBS for the Tier 1 conditions BRCA-related HBOC and Lynch syndrome. An online survey was distributed to 3,609 members of the National Society of Genetic Counselors. A total of 367 individuals participated in the study. Fifty percent of respondents felt that PBS for inherited cancer should not be offered; 93.3% felt that the current healthcare system is unprepared for implementation of PBS. However, most respondents agreed that PBS should be implemented within the next 10 years. Attitudes toward offering PBS were associated with respondents' work setting, cancer specialization, and perceived preparedness (p's < 0.05). The most commonly reported barriers to the implementation of PBS were shortage of genetic professionals and lack of infrastructure. Data in this study provide evidence that infrastructural barriers and educational gaps of non-genetic professionals would need to be addressed before successful integration of PBS into the healthcare system.
Assuntos
Neoplasias da Mama , Neoplasias Colorretais Hereditárias sem Polipose , Conselheiros , Síndrome Hereditária de Câncer de Mama e Ovário , Neoplasias Ovarianas , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Neoplasias Colorretais Hereditárias sem Polipose/diagnóstico , Neoplasias Colorretais Hereditárias sem Polipose/genética , Detecção Precoce de Câncer , Feminino , Aconselhamento Genético , Testes Genéticos , Síndrome Hereditária de Câncer de Mama e Ovário/diagnóstico , Síndrome Hereditária de Câncer de Mama e Ovário/genética , Humanos , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/genéticaRESUMO
BRCA1 and BRCA2 (BRCA1/2) pathogenic sequence variants (PSVs) confer elevated risks of multiple cancers. However, most BRCA1/2 PSVs reports focus on European ancestry individuals. Knowledge of the PSV distribution in African descent individuals is poorly understood. We undertook a systematic review of the published literature and publicly available databases reporting BRCA1/2 PSVs also accessed the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA) database to identify African or African descent individuals. Using these data, we inferred which of the BRCA PSVs were likely to be of African continental origin. Of the 43,817 BRCA1/2 PSV carriers in the CIMBA database, 469 (1%) were of African descent. Additional African descent individuals were identified in public databases (n = 291) and the literature (n = 601). We identified 164 unique BRCA1 and 173 unique BRCA2 PSVs in individuals of African ancestry. Of these, 83 BRCA1 and 91 BRCA2 PSVs are of likely or possible African origin. We observed numerous differences in the distribution of PSV type and function in African origin versus non-African origin PSVs. Research in populations of African ancestry with BRCA1/2 PSVs is needed to provide the information needed for clinical management and decision-making in African descent individuals worldwide.
Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , População Negra/genética , Predisposição Genética para Doença , Variação Genética , Alelos , Feminino , Estudos de Associação Genética , Humanos , Mutação , Vigilância da PopulaçãoRESUMO
BACKGROUND: The US Preventive Services Task Force (USPSTF) endorses routine screening for genetic risk of breast and/or ovarian cancer as a component of primary health care. Implementation of this recommendation may prove challenging, especially in clinics serving disadvantaged communities. METHODS: The authors tested the feasibility of implementing the USPSTF mandate at a federally qualified health center (FQHC) to identify women who were eligible for genetic counseling (GC). A 12-month usual-care phase was followed by a 12-month intervention phase, during which time cancer genetic risk assessment (CGRA) was systematically performed for all women aged 25 to 69 years who presented for an annual examination. Women who were eligible for GC were recruited to participate in the study. RESULTS: After initiating CGRA, 112 women who were eligible for GC consented to study participation, and 56% of them received a referral for GC from their primary care physician. A subgroup of 50 participants were seen by the same primary care physician during both the usual-care and intervention phases. None of these patients was referred for GC during usual care, compared with 64% after the initiation of CGRA (P < .001). Only 16% of referred participants attended a GC session. CONCLUSIONS: Implementing USPSTF recommendations for CGRA as a standard component of primary health care in FQHCs is feasible and improves referral of minority women for GC, but more work is needed to understand the beliefs and barriers that prevent many underserved women from accessing cancer genetic services.
Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Testes Genéticos , Implementação de Plano de Saúde , Médicos de Atenção Primária/estatística & dados numéricos , Encaminhamento e Consulta/estatística & dados numéricos , Adulto , Idoso , Neoplasias da Mama/epidemiologia , Chicago/epidemiologia , Estudos de Viabilidade , Feminino , Financiamento Governamental , Aconselhamento Genético/economia , Aconselhamento Genético/organização & administração , Aconselhamento Genético/estatística & dados numéricos , Testes Genéticos/economia , Testes Genéticos/métodos , Testes Genéticos/estatística & dados numéricos , Implementação de Plano de Saúde/economia , Implementação de Plano de Saúde/organização & administração , Implementação de Plano de Saúde/estatística & dados numéricos , Disparidades nos Níveis de Saúde , Humanos , Programas de Rastreamento/economia , Programas de Rastreamento/métodos , Programas de Rastreamento/estatística & dados numéricos , Pessoa de Meia-Idade , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/genética , Médicos de Atenção Primária/economia , Padrões de Prática Médica/economia , Padrões de Prática Médica/estatística & dados numéricos , Serviços Preventivos de Saúde/métodos , Atenção Primária à Saúde/métodos , Avaliação de Programas e Projetos de Saúde , Encaminhamento e Consulta/economia , Encaminhamento e Consulta/organização & administração , Medição de Risco , Estados Unidos/epidemiologiaRESUMO
The pathogenesis of atypical hemolytic uremic syndrome (aHUS) is strongly linked to dysregulation of the alternative pathway of the complement system. Mutations in complement genes have been identified in about two-thirds of cases, with 5% to 15% being in C3. In this study, 23 aHUS-associated genetic changes in C3 were characterized relative to their interaction with the control proteins factor H (FH), membrane cofactor protein (MCP; CD46), and complement receptor 1 (CR1; CD35). In surface plasmon resonance experiments, 17 mutant recombinant proteins demonstrated a defect in binding to FH and/or MCP, whereas 2 demonstrated reduced binding to CR1. In the majority of cases, decreased binding affinity translated to a decrease in proteolytic inactivation (known as cofactor activity) of C3b via FH and MCP. These results were used to map the putative binding regions of C3b involved in the interaction with MCP and CR1 and interrogated relative to known FH binding sites. Seventy-six percent of patients with C3 mutations had low C3 levels that correlated with disease severity. This study expands our knowledge of the functional consequences of aHUS-associated C3 mutations relative to the interaction of C3 with complement regulatory proteins mediating cofactor activity.
Assuntos
Síndrome Hemolítico-Urêmica Atípica/genética , Síndrome Hemolítico-Urêmica Atípica/metabolismo , Complemento C3/genética , Complemento C3/metabolismo , Mapas de Interação de Proteínas , Síndrome Hemolítico-Urêmica Atípica/patologia , Sítios de Ligação , Estudos de Coortes , Complemento C3/análise , Feminino , Humanos , Masculino , Modelos Moleculares , MutaçãoRESUMO
Complement dysregulation leads to atypical hemolytic uremic syndrome (aHUS), while ADAMTS13 deficiency causes thrombotic thrombocytopenic purpura. We investigated whether genetic variations in the ADAMTS13 gene partially explain the reduced activity known to occur in some patients with aHUS. We measured complement activity and ADAMTS13 function, and completed mutation screening of multiple complement genes and ADAMTS13 in a large cohort of aHUS patients. In over 50% of patients we identified complement gene mutations. Surprisingly, 80% of patients also carried at least 1 nonsynonymous change in ADAMTS13, and in 38% of patients, multiple ADAMTS13 variations were found. Six of the 9 amino acid substitutions in ADAMTS13 were common single nucleotide polymorphisms; however, 3 variants-A747V, V832M, and R1096H- were rare, with minor allele frequencies of 0.0094%, 0.5%, and 0.32%, respectively. Reduced complement and ADAMTS13 activity (<60% of normal activity) were found in over 60% and 50% of patients, respectively. We concluded that partial ADAMTS13 deficiency is a common finding in aHUS patients and that genetic screening and functional tests of ADAMTS13 should be considered in these patients.
Assuntos
Proteínas ADAM/deficiência , Proteínas ADAM/genética , Síndrome Hemolítico-Urêmica/sangue , Síndrome Hemolítico-Urêmica/genética , Proteína ADAMTS13 , Adolescente , Adulto , Alelos , Síndrome Hemolítico-Urêmica Atípica , Autoanticorpos/imunologia , Criança , Pré-Escolar , Estudos de Coortes , Fator H do Complemento/imunologia , DNA/genética , Feminino , Humanos , Lactente , Masculino , Mutação , Polimorfismo Genético , Proteínas Recombinantes de Fusão/metabolismo , Adulto JovemRESUMO
Atypical hemolytic uremic syndrome (aHUS) is a thrombotic microangiopathy caused by uncontrolled activation of the alternative pathway of complement at the cell surface level that leads to microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney failure. In approximately one half of affected patients, pathogenic loss-of-function variants in regulators of complement or gain-of-function variants in effectors of complement are identified, clearly implicating complement in aHUS. However, there are strong lines of evidence supporting the presence of additional genetic contributions to this disease. To identify novel aHUS-associated genes, we completed a comprehensive screen of the complement and coagulation pathways in 36 patients with sporadic aHUS using targeted genomic enrichment and massively parallel sequencing. After variant calling, quality control, and hard filtering, we identified 84 reported or novel nonsynonymous variants, 22 of which have been previously associated with disease. Using computational prediction methods, 20 of the remaining 62 variants were predicted to be deleterious. Consistent with published data, nearly one half of these 42 variants (19; 45%) were found in genes implicated in the pathogenesis of aHUS. Several genes in the coagulation pathway were also identified as important in the pathogenesis of aHUS. PLG, in particular, carried more pathogenic variants than any other coagulation gene, including three known plasminogen deficiency mutations and a predicted pathogenic variant. These data suggest that mutation screening in patients with aHUS should be broadened to include genes in the coagulation pathway.
Assuntos
Coagulação Sanguínea/genética , Proteínas do Sistema Complemento/genética , Síndrome Hemolítico-Urêmica/sangue , Síndrome Hemolítico-Urêmica/genética , Mutação , Plasminogênio/deficiência , Plasminogênio/genética , Adolescente , Adulto , Sequência de Aminoácidos , Síndrome Hemolítico-Urêmica Atípica , Criança , Pré-Escolar , Via Alternativa do Complemento/genética , Sequência Conservada , Variações do Número de Cópias de DNA , Feminino , Testes Genéticos , Variação Genética , Síndrome Hemolítico-Urêmica/etiologia , Humanos , Masculino , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos , Microangiopatias Trombóticas/sangue , Microangiopatias Trombóticas/genética , Microangiopatias Trombóticas/imunologia , Adulto JovemRESUMO
OBJECTIVES: To assess the association of socioeconomic demographics with recommendation for and uptake of risk-reducing bilateral salpingo-oophorectomy (rrBSO) in patients with BRCA1 and BRCA2 (BRCA1/2) mutations. DESIGN: Retrospective cohort, semistructured qualitative interviews. SETTING AND PARTICIPANTS: BRCA1/2 mutation carriers at an urban, public hospital with a racially and socioeconomically diverse population. INTERVENTION: None. PRIMARY AND SECONDARY OUTCOMES: The primary outcomes were rate of rrBSO recommendation and completion. Secondary outcomes were sociodemographic variables associated with rrBSO completion. RESULTS: The cohort included 167 patients with BRCA1/2 mutations of whom 39% identified as black (n=65), 35% white (n=59) and 19% Hispanic (n=32). Over 95% (n=159) received the recommendation for age-appropriate rrBSO, and 52% (n=87) underwent rrBSO. Women who completed rrBSO were older in univariable analysis (p=0.05), but not in multivariable analysis. Completion of rrBSO was associated with residence in zip codes with lower unemployment and documented recommendation for rrBSO (p<0.05). All subjects who still received care in the health system (n=79) were invited to complete interviews regarding rrBSO decision-making, but only four completed surveys for a response rate of 5.1%. Themes that emerged included menopause, emotional impact and familial support. CONCLUSIONS: In this understudied population, genetic counselling and surrogates of financial health were associated with rrBSO uptake, highlighting genetics referrals and addressing social determinants of health as opportunities to improve cancer prevention and reduce health inequities. Our study demonstrates a need for more culturally centred recruiting methods for qualitative research in marginalised communities to ensure adequate representation in the literature regarding rrBSO.
Assuntos
Hospitais Públicos , Neoplasias Ovarianas , Salpingo-Ooforectomia , Humanos , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/prevenção & controle , Hospitais Urbanos , Mutação , Genes BRCA1 , Genes BRCA2 , Fatores Socioeconômicos , Pesquisa Qualitativa , Proteína BRCA1/genética , Proteína BRCA2/genética , Predisposição Genética para DoençaRESUMO
The alternative pathway of the complement cascade plays a role in the pathogenesis of dense deposit disease (DDD). Deficiency of complement factor H and mutations in CFH associate with the development of DDD, but it is unknown whether allelic variants in other complement genes also associate with this disease. We studied patients with DDD and identified previously unreported sequence alterations in several genes in addition to allelic variants and haplotypes common to patients with DDD. We found that the likelihood of developing DDD increases with the presence of two or more risk alleles in CFH and C3. To determine the functional consequence of this finding, we measured the activity of the alternative pathway in serum samples from phenotypically normal controls genotyped for variants in CFH and C3. Alternative pathway activity was higher in the presence of variants associated with DDD. Taken together, these data confirm that DDD is a complex genetic disease and may provide targets for the development of disease-specific therapies.
Assuntos
Alelos , Proteínas do Sistema Complemento/genética , Variação Genética , Glomerulonefrite Membranoproliferativa/genética , Adolescente , Adulto , Biópsia , Ativação do Complemento/genética , Complemento C3/genética , Feminino , Glomerulonefrite Membranoproliferativa/etiologia , Humanos , Masculino , Mutação , Polimorfismo Genético , RiscoRESUMO
Atypical hemolytic uremic syndrome (aHUS) is a complex complement-mediated disease that progresses to end-stage renal failure (ESRF) in 50% of cases. Dysregulation of the alternative pathway (AP) of the complement cascade manifests as microangiopathic anaemia and thrombocytopenia. Multiple genes in the AP have been implicated in disease pathogenesis. Here, we report the clinical presentation of an affected patient that was inconsistent with genotype-phenotype data for carriers of CD46 mutations. Tests of AP function in this patient suggested additional genetic factors, and in-depth studies revealed a de novo heterozygous deletion that creates a novel CFH/CFHR1 fusion protein.
Assuntos
Proteínas Inativadoras do Complemento C3b/genética , Síndrome Hemolítico-Urêmica Atípica , Síndrome Hemolítico-Urêmica/genética , Humanos , Lactente , Masculino , Proteína Cofatora de Membrana , Família Multigênica/genética , Deleção de SequênciaRESUMO
Atypical hemolytic uremic syndrome (aHUS) is characterized by acute renal failure, thrombocytopenia and microangiopathic hemolytic anemia, and occurs with an estimated incidence in the USA of 2 per 1,000,000. Disease pathogenesis is related to dysregulation of the alternative pathway (AP) of the complement cascade at the level of the cell membrane secondary to mutations in a number of complement genes including complement factor H (CFH), complement factor H-related 5 (CFHR5), complement factor I (CFI), CD46 (MCP), complement factor B (CFB), complement component 3 (C3) and thrombomodulin (THBD). Since aHUS is rare, mutation rate data in large patient cohorts are scarce. Here we present the first cohort of American patients in whom mutation screening was completed on all genes currently implicated in aHUS. In addition to identifying a number of novel variants, we provide information on the relative frequency of mutations in these genes in an American aHUS population. Twelve percent (12%) of patients carrying disease-associated genetic variants segregated mutations in more than one gene mandating comprehensive genetic testing in the diagnosis and management of these patients.
Assuntos
Via Alternativa do Complemento/genética , Proteínas do Sistema Complemento/genética , Síndrome Hemolítico-Urêmica/genética , Mutação , Estudos de Coortes , Complemento C3/genética , Fator B do Complemento/genética , Fator H do Complemento/genética , Fator I do Complemento/genética , Análise Mutacional de DNA , Frequência do Gene , Predisposição Genética para Doença , Síndrome Hemolítico-Urêmica/epidemiologia , Humanos , Incidência , Proteína Cofatora de Membrana/genética , Trombomodulina/genética , Estados Unidos/epidemiologiaRESUMO
We report the case of an 8-year-old girl diagnosed with atypical hemolytic uremic syndrome (aHUS) with a complement factor B (CFB) gene mutation. aHUS is a disease of complement dysregulation. In approximately 50% of patients, mutations are identified in genes encoding regulators of complement-complement factor H (CFH), membrane cofactor protein or complement factor I (CFI)-or activators of complement-complement factor B (CFB) or C3. The mutation in this patient was identified in exon 12 of CFB and changes a lysine at amino acid position 533 to an arginine (c.1598A>G p.Lys533Arg). The two other mutations previously reported in CFB associated with aHUS are c.858C>G, p.F286L in exon 6 and c.967A>Gp.K323E in exon 7.
Assuntos
Fator B do Complemento/genética , Síndrome Hemolítico-Urêmica/genética , Mutação , Substituição de Aminoácidos , Criança , Análise Mutacional de DNA , Éxons , Evolução Fatal , Feminino , Predisposição Genética para Doença , Síndrome Hemolítico-Urêmica/diagnóstico , Síndrome Hemolítico-Urêmica/imunologia , Síndrome Hemolítico-Urêmica/terapia , Humanos , FenótipoRESUMO
Exogenous overexpression of the metastasis suppressor gene Nm23-H1 reduces the metastatic potential of multiple types of cancer cells and suppresses in vitro tumor cell motility and invasion. Mutational analysis of Nm23-H1 revealed that substitution mutants P96S and S120G did not inhibit motility and invasion. To elucidate the molecular mechanism of Nm23-H1 motility suppression, expression microarray analysis of an MDA-MB-435 cancer cell line overexpressing wild-type Nm23-H1 was done and cross-compared with expression profiles from lines expressing the P96S and S120G mutants. Nine genes, MET, PTN, SMO, FZD1, L1CAM, MMP2, NETO2, CTGF, and EDG2, were down-regulated by wild-type but not by mutant Nm23-H1 expression. Reduced expression of these genes coincident with elevated Nm23-H1 expression was observed in human breast tumor cohorts, a panel of breast carcinoma cell lines, and hepatocellular carcinomas from control versus Nm23-M1 knockout mice. The functional significance of the down-regulated genes was assessed by transfection and in vitro motility assays. Only EDG2 overexpression significantly restored motility to Nm23-H1-suppressed cancer cells, enhancing motility by 60-fold in these cells. In addition, silencing EDG2 expression with small interfering RNA reduced the motile phenotype of metastatic breast cancer cells. These data suggest that Nm23-H1 suppresses metastasis, at least in part, through down-regulation of EDG2 expression.
Assuntos
Neoplasias da Mama/patologia , Regulação Neoplásica da Expressão Gênica/fisiologia , Núcleosídeo-Difosfato Quinase/fisiologia , Receptores de Ácidos Lisofosfatídicos/metabolismo , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Movimento Celular , Estudos de Coortes , Colágeno/metabolismo , Regulação para Baixo , Combinação de Medicamentos , Perfilação da Expressão Gênica , Inativação Gênica , Humanos , Immunoblotting , Técnicas Imunoenzimáticas , Laminina/metabolismo , Camundongos , Camundongos Knockout , Nucleosídeo NM23 Difosfato Quinases , Análise de Sequência com Séries de Oligonucleotídeos , Proteoglicanas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Ácidos Lisofosfatídicos/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais CultivadasRESUMO
Colorectal cancer affects 1 in 20 men and women in their lifetime. About 30% of these cases have been shown to be familial while only about 5% are associated with a highly penetrant hereditary colon cancer syndrome. In many familial cases, however, no mutation in the commonly implicated CRC genes is found. With the development of next-generation sequencing, testing laboratories are now able to offer hereditary gastrointestinal panel testing, which allows for the simultaneous sequencing of a much broader set of genes associated with CRC. We discuss the advantages and disadvantages of such testing to inform best clinical practice.
RESUMO
Genes that code for proteins involved in organelle biogenesis and intracellular trafficking produce products that are critical in normal cell function . Conserved orthologs of these are present in most or all eukaryotes, including Drosophila melanogaster Some of these genes were originally identified as eye color mutants with decreases in both types of pigments found in the fly eye. These criteria were used for identification of such genes, four eye color mutations that are not annotated in the genome sequence: chocolate, maroon, mahogany, and red Malpighian tubules were molecularly mapped and their genome sequences have been evaluated. Mapping was performed using deletion analysis and complementation tests. chocolate is an allele of the VhaAC39-1 gene, which is an ortholog of the Vacuolar H+ ATPase AC39 subunit 1. maroon corresponds to the Vps16A gene and its product is part of the HOPS complex, which participates in transport and organelle fusion. red Malpighian tubule is the CG12207 gene, which encodes a protein of unknown function that includes a LysM domain. mahogany is the CG13646 gene, which is predicted to be an amino acid transporter. The strategy of identifying eye color genes based on perturbations in quantities of both types of eye color pigments has proven useful in identifying proteins involved in trafficking and biogenesis of lysosome-related organelles. Mutants of these genes can form the basis of valuable in vivo models to understand these processes.