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1.
Br J Cancer ; 130(5): 808-818, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38225422

RESUMO

BACKGROUND: Dihydropyrimidine dehydrogenase (DPD) deficiency is the main known cause of life-threatening fluoropyrimidine (FP)-induced toxicities. We conducted a meta-analysis on individual patient data to assess the contribution of deleterious DPYD variants *2A/D949V/*13/HapB3 (recommended by EMA) and clinical factors, for predicting G4-5 toxicity. METHODS: Study eligibility criteria included recruitment of Caucasian patients without DPD-based FP-dose adjustment. Main endpoint was 12-week haematological or digestive G4-5 toxicity. The value of DPYD variants *2A/p.D949V/*13 merged, HapB3, and MIR27A rs895819 was evaluated using multivariable logistic models (AUC). RESULTS: Among 25 eligible studies, complete clinical variables and primary endpoint were available in 15 studies (8733 patients). Twelve-week G4-5 toxicity prevalence was 7.3% (641 events). The clinical model included age, sex, body mass index, schedule of FP-administration, concomitant anticancer drugs. Adding *2A/p.D949V/*13 variants (at least one allele, prevalence 2.2%, OR 9.5 [95%CI 6.7-13.5]) significantly improved the model (p < 0.0001). The addition of HapB3 (prevalence 4.0%, 98.6% heterozygous), in spite of significant association with toxicity (OR 1.8 [95%CI 1.2-2.7]), did not improve the model. MIR27A rs895819 was not associated with toxicity, irrespective of DPYD variants. CONCLUSIONS: FUSAFE meta-analysis highlights the major relevance of DPYD *2A/p.D949V/*13 combined with clinical variables to identify patients at risk of very severe FP-related toxicity.


Assuntos
Antineoplásicos , Deficiência da Di-Hidropirimidina Desidrogenase , Humanos , Fluoruracila/efeitos adversos , Di-Hidrouracila Desidrogenase (NADP)/genética , Heterozigoto , Genótipo , Capecitabina/efeitos adversos
2.
Arch Gynecol Obstet ; 303(6): 1557-1567, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33245408

RESUMO

PURPOSE: TP53germline (g) mutations, associated with the Li-Fraumeni syndrome (LFS), have rarely been reported in the context of hereditary breast and ovarian cancer (HBOC). The prevalence and cancer risks in this target group are unknown and counseling remains challenging. Notably an extensive high-risk surveillance program is implemented, which evokes substantial psychological discomfort. Emphasizing the lack of consensus about clinical implications, we aim to further characterize TP53g mutations in HBOC families. METHODS: Next-generation sequencing was conducted on 1876 breast cancer (BC) patients who fulfilled the inclusion criteria for HBOC. RESULTS: (Likely) pathogenic variants in TP53 gene were present in 0.6% of the BC cohort with higher occurrence in early onset BC < 36 years. (1.1%) and bilateral vs. unilateral BC (1.1% vs. 0.3%). Two out of eleven patients with a (likely) pathogenic TP53g variant (c.542G > A; c.375G > A) did not comply with classic LFS/Chompret criteria. Albeit located in the DNA-binding domain of the p53-protein and therefore revealing no difference to LFS-related variants, they only displayed a medium transactivity reduction constituting a retainment of wildtype-like anti-proliferative functionality. CONCLUSION: Among our cohort of HBOC families, we were able to describe a clinical subgroup, which is distinct from the classic LFS-families. Strikingly, two families did not adhere to the LFS criteria, and functional analysis revealed a reduced impact on TP53 activity, which may suit to the attenuated phenotype. This is an approach that could be useful in developing individualized screening efforts for TP53g mutation carrier in HBOC families. Due to the low incidence, national/international cooperation is necessary to further explore clinical implications. This might allow providing directions for clinical recommendations in the future.


Assuntos
Neoplasias da Mama , Síndrome de Li-Fraumeni , Neoplasias Ovarianas , Proteína Supressora de Tumor p53/genética , Neoplasias da Mama/genética , Feminino , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Humanos , Síndrome de Li-Fraumeni/genética , Masculino , Pessoa de Meia-Idade , Neoplasias Ovarianas/genética
3.
Am J Cancer Res ; 10(6): 1785-1792, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32642290

RESUMO

In normal physiology, kallikrein-related peptidase 7 (KLK7), together with other members of the kallikrein-related peptidase family, is mainly involved in skin desquamation and keratinization processes. Moreover, expression of KLK7 was shown in various tumor types to be dysregulated and to correlate to patients' survival time. However, there are contradictory reports in breast cancer whether KLK7 represents an unfavorable or favorable prognostic biomarker. In the present study, we examined the prognostic value of KLK7 protein expression in triple-negative breast cancer (TNBC), determined by immunohistochemistry (IHC). A cohort encompassing 133 TNBC specimens, present on tissue microarrays, was analyzed. For quantification of the staining intensity, an automated digital IHC image analysis algorithm was applied. In both Kaplan-Meier and univariate Cox analyses, elevated KLK7 protein levels were significantly linked with prolonged overall survival (OS). In multivariable Cox analysis, addition of KLK7 immunoreactivity scores to the base model (including the clinical parameters age, tumor size, and nodal status) demonstrated that KLK7 protein expression remained as a statistically significant, independent parameter for prolonged OS. These results strongly indicate that KLK7 is a favorable prognostic biomarker in triple-negative breast cancer.

4.
Int J Mol Sci ; 21(7)2020 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-32244351

RESUMO

Gestational diabetes mellitus (GDM) is the most common pregnancy-associated metabolic disorder that negatively impacts on the health of both mothers and their offspring in the long-term. The molecular mechanisms involved are not fully understood. As in other states of insulin resistance, a disproportionate immune response in GDM leads to a state of chronic low-grade inflammation. Galectin-2 exerts regulatory effects on different immune cells. This study investigated galectin-2 expression in the placenta of 40 GDM patients and 40 controls, in a sex-specific manner. Immunohistochemistry was used for semi-quantitative analysis of expression strength. The phenotypes of galectin-2 expressing cells were characterized through double immunofluorescence. We found a significant up-regulation of galectin-2 in the fetal syncytiotrophoblast, as well as in the maternal decidua of GDM placentas. Double staining showed a strong galectin-2 expression in extra villous trophoblast cells and fetal endothelial cells in GDM. These findings present the first systematic investigation of galectin-2 in GDM. The findings contribute to the emerging understanding of the role of immunomodulation and inflammation in GDM and of galectin-2 itself. This might also have implications for the long-term cardiovascular health of the offspring.


Assuntos
Diabetes Gestacional/metabolismo , Galectina 2/metabolismo , Placenta/metabolismo , Placenta/patologia , Adulto , Colo/patologia , Células Endoteliais/metabolismo , Feminino , Feto/metabolismo , Galectina 2/genética , Regulação da Expressão Gênica , Humanos , Inflamação , Resistência à Insulina , Masculino , Gravidez , Complicações na Gravidez/metabolismo , Trofoblastos/metabolismo , Trofoblastos/patologia
5.
Womens Health Issues ; 28(5): 415-420, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30061032

RESUMO

BACKGROUND: Although the contraceptive vaginal ring (CVR) has been available in Canada since 2001, overall use and availability remain low compared with other combined hormonal contraceptive methods. We aimed to explore women's experiences with the CVR in Ontario as well as factors that influenced their decisions to choose the method and continue/discontinue use. METHODS: We conducted a multimethod qualitative study that consisted of an anonymous online survey and in-depth telephone interviews with a subset of survey participants. We used descriptive statistics to analyze the survey data and analyzed our interviews for content and themes using both deductive and inductive techniques. RESULTS: From May to July 2015, we received 103 survey responses and conducted 29 in-depth interviews. Many participants described positive experiences with the CVR and found it to be an especially convenient method. Women who discontinued use of the CVR cited high costs, access barriers, and negative media reports as important factors in their decision. Our participants primarily relied on their physicians for contraceptive information but did not feel fully informed about potential side effects. Several women identified the CVR as an "in between" method in the transition from oral contraceptive pills to the intrauterine device. CONCLUSIONS: Our findings suggest that the CVR represents a convenient and desirable contraceptive option for some women. However, participants expressed a desire for health care providers to provide more comprehensive information about a full range of contraceptive methods. Improving access to a full range of low-cost contraceptives in Ontario seems to be warranted.


Assuntos
Método de Barreira Anticoncepção , Dispositivos Anticoncepcionais Femininos , Acessibilidade aos Serviços de Saúde , Aceitação pelo Paciente de Cuidados de Saúde , Adulto , Anticoncepção , Método de Barreira Anticoncepção/economia , Método de Barreira Anticoncepção/estatística & dados numéricos , Dispositivos Anticoncepcionais Femininos/economia , Dispositivos Anticoncepcionais Femininos/estatística & dados numéricos , Dispositivos Anticoncepcionais Femininos/provisão & distribuição , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Entrevistas como Assunto , Ontário , Pesquisa Qualitativa , Adulto Jovem
6.
Cancer Med ; 7(4): 1349-1358, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29522266

RESUMO

The prevalence of germ line mutations in non-BRCA1/2 genes associated with hereditary breast cancer (BC) is low, and the role of some of these genes in BC predisposition and pathogenesis is conflicting. In this study, 5589 consecutive BC index patients negative for pathogenic BRCA1/2 mutations and 2189 female controls were screened for germ line mutations in eight cancer predisposition genes (ATM, CDH1, CHEK2, NBN, PALB2, RAD51C, RAD51D, and TP53). All patients met the inclusion criteria of the German Consortium for Hereditary Breast and Ovarian Cancer for germ line testing. The highest mutation prevalence was observed in the CHEK2 gene (2.5%), followed by ATM (1.5%) and PALB2 (1.2%). The mutation prevalence in each of the remaining genes was 0.3% or lower. Using Exome Aggregation Consortium control data, we confirm significant associations of heterozygous germ line mutations with BC for ATM (OR: 3.63, 95%CI: 2.67-4.94), CDH1 (OR: 17.04, 95%CI: 3.54-82), CHEK2 (OR: 2.93, 95%CI: 2.29-3.75), PALB2 (OR: 9.53, 95%CI: 6.25-14.51), and TP53 (OR: 7.30, 95%CI: 1.22-43.68). NBN germ line mutations were not significantly associated with BC risk (OR:1.39, 95%CI: 0.73-2.64). Due to their low mutation prevalence, the RAD51C and RAD51D genes require further investigation. Compared with control datasets, predicted damaging rare missense variants were significantly more prevalent in CHEK2 and TP53 in BC index patients. Compared with the overall sample, only TP53 mutation carriers show a significantly younger age at first BC diagnosis. We demonstrate a significant association of deleterious variants in the CHEK2, PALB2, and TP53 genes with bilateral BC. Both, ATM and CHEK2, were negatively associated with triple-negative breast cancer (TNBC) and estrogen receptor (ER)-negative tumor phenotypes. A particularly high CHEK2 mutation prevalence (5.2%) was observed in patients with human epidermal growth factor receptor 2 (HER2)-positive tumors.


Assuntos
Biomarcadores Tumorais , Genes BRCA1 , Genes BRCA2 , Síndrome Hereditária de Câncer de Mama e Ovário/diagnóstico , Síndrome Hereditária de Câncer de Mama e Ovário/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Testes Genéticos/métodos , Variação Genética , Síndrome Hereditária de Câncer de Mama e Ovário/epidemiologia , Humanos , Pessoa de Meia-Idade , Razão de Chances , Prevalência , Adulto Jovem
7.
Oncotarget ; 9(5): 6369-6390, 2018 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-29464079

RESUMO

The tetraspanin and tumor suppressor KAI1 is downregulated or lost in many cancers which correlates with poor prognosis. KAI1 acts via physical/functional crosstalk with other membrane receptors. Also, a splice variant of KAI1 (KAI1-SP) has been identified indicative of poor prognosis. We here characterized differential effects of the two KAI1 variants on tumor biological events involving integrin (αvß3) and/or epidermal growth factor receptor (EGF-R). In MDA-MB-231 and -435 breast cancer cells, differential effects were documented on the expression levels of the tumor biologically relevant integrin αvß3 which colocalized with KAI1-WT but not with KAI1-SP. Cellular motility was assessed by video image processing, including motion detection and vector analysis for the quantification and visualization of cell motion parameters. In MDA-MB-231 cells, KAI1-SP provoked a quicker wound gap closure and higher closure rates than KAI1-WT, also reflected by different velocities and average motion amplitudes of singular cells. KAI1-SP induced highest cell motion adjacent to the wound gap borders, whereas in MDA-MB-435 cells a comparable induction of both KAI1 variants was noticed. Moreover, while KAI1-WT reduced cell growth, KAI1-SP significantly increased it going along with a pronounced EGF-R upregulation. KAI1-SP-induced cell migration and proliferation was accompanied by the activation of the focal adhesion and Src kinase. Our findings suggest that splicing of KAI1 does not only abrogate its tumor suppressive functions, but even more, promotes tumor biological effects in favor of cancer progression and metastasis.

8.
Int J Oncol ; 52(3): 755-767, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29328369

RESUMO

Triple-negative breast cancer (TNBC) constitutes a heterogeneous breast cancer subgroup with poor prognosis; survival rates are likely to be lower with TNBC compared to other breast cancer subgroups. For this disease, systemic adjuvant chemotherapy regimens often yield suboptimal clinical results. To improve treatment regimens in TNBC, identification of molecular biomarkers may help to select patients for individualized adjuvant therapy. Evidence has accumulated that determination of the methylation status of the PITX2 gene provides a predictive value in various breast cancer subgroups, either treated with endocrine-based therapy or anthracycline-containing chemotherapy. To further explore the validity of this novel predictive candidate biomarker, in the present exploratory retrospective study, determination of the PITX2 DNA-methylation status was assessed for non-metastatic TNBC patients treated with adjuvant anthracycline-based chemotherapy by molecular analysis of breast cancer tissues. The PITX2 DNA-methylation status was determined in fresh-frozen tumor tissue specimens (n=56) by methylation-specific qRT-PCR (qMSP) and the data related to disease-free and overall survival, applying an optimized DNA-methylation score of 6.35%. For non-metastatic TNBC patients treated with adjuvant systemic anthracycline-based chemotherapy, a low PITX2 DNA-methylation status (<6.35) defines TNBC patients with poor disease-free and overall survival. Univariate and multivariate analyses demonstrate the statistically independent predictive value of PITX2 DNA-methylation. For non-metastatic TNBC patients, selective determination of the PITX2 DNA-methylation status may serve as a cancer biomarker for predicting response to anthracycline-based adjuvant chemotherapy. The assay based on methylation of the PIXT2 gene can be applied to frozen and routinely available formalin-fixed, paraffin-embedded (FFPE) breast cancer tumor tissues that will not only define those TNBC patients who may benefit from anthracycline-based chemotherapy but also those who should be spared the necessity of such potentially toxic treatment. Such patients should be allocated to alternative treatment options.


Assuntos
Antraciclinas/uso terapêutico , Antibióticos Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/genética , Proteínas de Homeodomínio/genética , Fatores de Transcrição/genética , Neoplasias de Mama Triplo Negativas/terapia , Adulto , Idoso , Mama/patologia , Mama/cirurgia , Quimioterapia Adjuvante/métodos , Metilação de DNA , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Seleção de Pacientes , Projetos Piloto , Estudos Retrospectivos , Resultado do Tratamento , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/mortalidade , Neoplasias de Mama Triplo Negativas/patologia , Proteína Homeobox PITX2
9.
Breast Cancer Res ; 20(1): 7, 2018 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-29368626

RESUMO

BACKGROUND: Germline mutations in the BRIP1 gene have been described as conferring a moderate risk for ovarian cancer (OC), while the role of BRIP1 in breast cancer (BC) pathogenesis remains controversial. METHODS: To assess the role of deleterious BRIP1 germline mutations in BC/OC predisposition, 6341 well-characterized index patients with BC, 706 index patients with OC, and 2189 geographically matched female controls were screened for loss-of-function (LoF) mutations and potentially damaging missense variants. All index patients met the inclusion criteria of the German Consortium for Hereditary Breast and Ovarian Cancer for germline testing and tested negative for pathogenic BRCA1/2 variants. RESULTS: BRIP1 LoF mutations confer a high OC risk in familial index patients (odds ratio (OR) = 20.97, 95% confidence interval (CI) = 12.02-36.57, P < 0.0001) and in the subgroup of index patients with late-onset OC (OR = 29.91, 95% CI = 14.99-59.66, P < 0.0001). No significant association of BRIP1 LoF mutations with familial BC was observed (OR = 1.81 95% CI = 1.00-3.30, P = 0.0623). In the subgroup of familial BC index patients without a family history of OC there was also no apparent association (OR = 1.42, 95% CI = 0.70-2.90, P = 0.3030). In 1027 familial BC index patients with a family history of OC, the BRIP1 mutation prevalence was significantly higher than that observed in controls (OR = 3.59, 95% CI = 1.43-9.01; P = 0.0168). Based on the negative association between BRIP1 LoF mutations and familial BC in the absence of an OC family history, we conclude that the elevated mutation prevalence in the latter cohort was driven by the occurrence of OC in these families. Compared with controls, predicted damaging rare missense variants were significantly more prevalent in OC (P = 0.0014) but not in BC (P = 0.0693) patients. CONCLUSIONS: To avoid ambiguous results, studies aimed at assessing the impact of candidate predisposition gene mutations on BC risk might differentiate between BC index patients with an OC family history and those without. In familial cases, we suggest that BRIP1 is a high-risk gene for late-onset OC but not a BC predisposition gene, though minor effects cannot be excluded.


Assuntos
Neoplasias da Mama/genética , Proteínas de Grupos de Complementação da Anemia de Fanconi/genética , Predisposição Genética para Doença , Neoplasias Ovarianas/genética , RNA Helicases/genética , Adulto , Idoso , Neoplasias da Mama/patologia , Feminino , Estudos de Associação Genética , Mutação em Linhagem Germinativa , Humanos , Mutação com Perda de Função/genética , Pessoa de Meia-Idade , Neoplasias Ovarianas/patologia , Linhagem , Fatores de Risco
10.
Biol Chem ; 398(10): 1151-1164, 2017 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-28755528

RESUMO

Triple-negative breast cancer (TNBC), lacking the steroid hormone receptors ER and PR and the oncoprotein HER2, is characterized by its aggressive pattern and insensitivity to endocrine and HER2-directed therapy. Human kallikrein-related peptidases KLK1-15 provide a rich source of serine protease-type biomarkers associated with tumor growth and cancer progression for a variety of malignant diseases. In this study, recombinant KLK4 protein was generated and affinity-purified KLK4-directed polyclonal antibody pAb587 established to allow localization of KLK4 protein expression in tumor cell lines and archived formalin-fixed, paraffin-embedded TNBC tumor tissue specimens. For this, KLK4 protein expression was assessed by immunohistochemistry in primary tumor tissue sections (tissue microarrays) of 188 TNBC patients, mainly treated with anthracycline- or CMF-based polychemotherapy. KLK4 protein is localized in the cytoplasm of tumor and stroma cells. In this patient cohort, elevated stroma cell KLK4 expression, but not tumor cell KLK4 expression, is predictive for poor disease-free survival by univariate analysis (hazard ratio: 2.26, p=0.001) and multivariable analysis (hazard ratio: 2.12, p<0.01). Likewise, univariate analysis revealed a trend for statistical significance of elevated KLK4 stroma cell expression for overall survival of TNBC patients as well.


Assuntos
Biomarcadores Tumorais/metabolismo , Calicreínas/metabolismo , Neoplasias de Mama Triplo Negativas/enzimologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/biossíntese , Humanos , Calicreínas/biossíntese , Análise Multivariada , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Células Tumorais Cultivadas
11.
JAMA Oncol ; 3(9): 1245-1248, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28033443

RESUMO

IMPORTANCE: Germline mutations in established moderately or highly penetrant risk genes for breast cancer (BC) and/or ovarian cancer (OC), including BRCA1 and BRCA2, explain fewer than half of all familial BC and/or OC cases. Based on the genotyping of 2 loss-of-function (LoF) variants c.5101C>T (p.GIn1701Ter [rs147021911]) and c.5791C>T (p.Arg1931Ter [rs144567652]), the FANCM gene has been suggested as a novel BC predisposition gene, while the analysis of the entire coding region of the FANCM gene in familial index cases and geographically matched controls is pending. OBJECTIVES: To assess the mutational spectrum within the FANCM gene, and to determine a potential association of LoF germline mutations within the FANCM gene with BC and/or OC risk. DESIGN, SETTING, AND PARTICIPANTS: For the purpose of identification and characterization of novel BC and/or OC predisposition genes, a total of 2047 well-characterized familial BC index cases, 628 OC cases, and 2187 geographically matched controls were screened for LoF mutations within the FANCM gene by next-generation sequencing. All patients previously tested negative for pathogenic BRCA1 and BRCA2 mutations. All data collection occurred between June 1, 2013, and April 30, 2016. Data analysis was performed from May 1, 2016, to July 1, 2016. MAIN OUTCOMES AND MEASURES: FANCM LoF mutation frequencies in patients with BC and/or OC were compared with the FANCM LoF mutation frequencies in geographically matched controls by univariate logistic regression. Positive associations were stratified by age at onset and cancer family history. RESULTS: In this case-control study, 2047 well-characterized familial female BC index cases, 628 OC cases, and 2187 geographically matched controls were screened for truncating FANCM alterations. Heterozygous LoF mutations within the FANCM gene were significantly associated with familial BC risk, with an overall odds ratio (OR) of 2.05 (95% CI, 0.94-4.54; P = .049) and a mutation frequency of 1.03% in index cases. In familial patients whose BC onset was before age 51 years, an elevated OR of 2.44 (95% CI, 1.08-5.59; P = .02) was observed. A more pronounced association was identified for patients with a triple-negative BC tumor phenotype (OR, 3.75; 95% CI, 1.00-12.85; P = .02). No significant association was detected for unselected OC cases (OR, 1.74; 95% CI, 0.57-5.08; P = .27). CONCLUSIONS AND RELEVANCE: Based on the significant associations of heterozygous LoF mutations with early-onset or triple-negative BC, FANCM should be included in diagnostic gene panel testing for individual risk assessment. Larger studies are required to determine age-dependent disease risks for BC and to assess a potential role of FANCM mutations in OC pathogenesis.


Assuntos
Neoplasias da Mama/genética , DNA Helicases/genética , Predisposição Genética para Doença , Neoplasias Ovarianas/genética , Adulto , Idade de Início , Idoso , Estudos de Casos e Controles , Análise Mutacional de DNA , Feminino , Mutação em Linhagem Germinativa , Heterozigoto , Humanos , Pessoa de Meia-Idade , Taxa de Mutação , Neoplasias de Mama Triplo Negativas/genética
12.
BMC Cancer ; 16(1): 811, 2016 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-27756336

RESUMO

BACKGROUND: Triple-negative breast cancer (TNBC) with a BRCA1-like molecular signature has been demonstrated to remarkably respond to platinum-based chemotherapy and might be suited for a future treatment with poly(ADP-ribose)polymerase (PARP) inhibitors. In order to rapidly assess this signature we have previously developed a multiplex-ligation-dependent probe amplification (MLPA)-based assay. Here we present an independent validation of this assay to confirm its important clinical impact. METHODS: One-hundred-forty-four TNBC tumor specimens were analysed by the MLPA-based "BRCA1-like" test. Classification into BRCA1-like vs. non-BRCA1-like samples was performed by our formerly established nearest shrunken centroids classifier. Data were subsequently compared with the BRCA1-mutation/methylation status of the samples. T-lymphocyte infiltration and expression of the main target of PARP inhibitors, PARP1, were assessed on a subset of samples by immunohistochemistry. Data acquisition and interpretation was performed in a blinded manner. RESULTS: In the studied TNBC cohort, 63 out of 144 (44 %) tumors were classified into the BRCA1-like category. Among these, the MLPA test correctly predicted 15 out of 18 (83 %) samples with a pathogenic BRCA1-mutation and 20 of 22 (91 %) samples exhibiting BRCA1-promoter methylation. Five false-negative samples were observed. We identified high lymphocyte infiltration as one possible basis for misclassification. However, two falsely classified BRCA1-mutated tumors were also characterized by rather non-BRCA1-associated histopathological features such as borderline ER expression. The BRCA1-like vs. non-BRCA1-like signature was specifically enriched in high-grade (G3) cancers (90 % vs. 58 %, p = 0.0004) and was also frequent in tumors with strong (3+) nuclear PARP1 expression (37 % vs. 16 %; p = 0.087). CONCLUSIONS: This validation study confirmed the good performance of the initial MLPA assay which might thus serve as a valuable tool to select patients for platinum-based chemotherapy regimens. Moreover, frequent PARP1 upregulation in BRCA1-like tumors may also point to susceptibility to treatment with PARP inhibitors. Limitations are the requirement of high tumor content and high-quality DNA.


Assuntos
Proteína BRCA1/genética , Biomarcadores Tumorais , Mapeamento Cromossômico , Neoplasias de Mama Triplo Negativas/genética , Adulto , Idoso , Proteína BRCA1/metabolismo , Terapia Combinada , Metilação de DNA , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Multiplex , Mutação , Gradação de Tumores , Poli(ADP-Ribose) Polimerase-1/metabolismo , Regiões Promotoras Genéticas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Neoplasias de Mama Triplo Negativas/diagnóstico , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/terapia , Carga Tumoral
13.
BMC Cancer ; 16: 615, 2016 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-27502396

RESUMO

BACKGROUND: Due to lack of a targeted therapy for the triple-negative breast cancer (TNBC) patients, it is important to explore this aggressive breast cancer type in more detail and to establish novel therapeutic approaches. TNBC is defined negative for the protein expression of oestrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2). One prominent feature of this cancer type is the frequent overexpression of major components of the urokinase-type plasminogen activator system (uPAS) including uPA, its receptor uPAR and the inhibitor PAI-1, which may be valuable as therapeutic targets. METHODS: Direct interactions of uPAR with interactors were demonstrated by immunoprecipitations and proximity ligation assays. For stable knockdowns of target proteins, lentiviral vectors were used and the effects were analysed by immunoblottings and using in vitro cell viability, migration and invasion assays. Immunohistochemical and statistical analyses of biomarkers and clinical parameters were conducted in a TNBC cohort (n = 174). RESULTS: Direct tumour-promoting interactions of uPAR with uPA and the insulin-like growth factor receptor 1 (IGF1R) were shown in TNBC cells and these interactions were significantly reduced (p = 0.001) when uPAR was downregulated. The combined knockdown of uPAR and uPA or IGF1R additively and significantly reduced cell viability, migration and invasion of the model cell lines. In TNBC tissue, the complexes formed by uPAR with uPA or with IGF1R significantly correlated with the histological grade (p = 0.0019) as well as with cathepsin B and D (p ≤ 0.0001) that are implicated in cell invasion and metastasis. CONCLUSIONS: Our outcomes show that not only overexpressed biomarkers promote tumourigenesis, but rather their interactions further potentiate tumour progression. This study emphasises the potential of combined approaches targeting uPAR and its interactors with regard to an improved therapy of TNBC.


Assuntos
Receptores de Somatomedina/metabolismo , Receptores de Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Células MCF-7 , Gradação de Tumores , Receptor IGF Tipo 1 , Neoplasias de Mama Triplo Negativas/metabolismo
14.
Lancet Oncol ; 16(16): 1639-50, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26603945

RESUMO

BACKGROUND: The best-known cause of intolerance to fluoropyrimidines is dihydropyrimidine dehydrogenase (DPD) deficiency, which can result from deleterious polymorphisms in the gene encoding DPD (DPYD), including DPYD*2A and c.2846A>T. Three other variants-DPYD c.1679T>G, c.1236G>A/HapB3, and c.1601G>A-have been associated with DPD deficiency, but no definitive evidence for the clinical validity of these variants is available. The primary objective of this systematic review and meta-analysis was to assess the clinical validity of c.1679T>G, c.1236G>A/HapB3, and c.1601G>A as predictors of severe fluoropyrimidine-associated toxicity. METHODS: We did a systematic review of the literature published before Dec 17, 2014, to identify cohort studies investigating associations between DPYD c.1679T>G, c.1236G>A/HapB3, and c.1601G>A and severe (grade ≥3) fluoropyrimidine-associated toxicity in patients treated with fluoropyrimidines (fluorouracil, capecitabine, or tegafur-uracil as single agents, in combination with other anticancer drugs, or with radiotherapy). Individual patient data were retrieved and analysed in a multivariable analysis to obtain an adjusted relative risk (RR). Effect estimates were pooled by use of a random-effects meta-analysis. The threshold for significance was set at a p value of less than 0·0167 (Bonferroni correction). FINDINGS: 7365 patients from eight studies were included in the meta-analysis. DPYD c.1679T>G was significantly associated with fluoropyrimidine-associated toxicity (adjusted RR 4·40, 95% CI 2·08-9·30, p<0·0001), as was c.1236G>A/HapB3 (1·59, 1·29-1·97, p<0·0001). The association between c.1601G>A and fluoropyrimidine-associated toxicity was not significant (adjusted RR 1·52, 95% CI 0·86-2·70, p=0·15). Analysis of individual types of toxicity showed consistent associations of c.1679T>G and c.1236G>A/HapB3 with gastrointestinal toxicity (adjusted RR 5·72, 95% CI 1·40-23·33, p=0·015; and 2·04, 1·49-2·78, p<0·0001, respectively) and haematological toxicity (adjusted RR 9·76, 95% CI 3·03-31·48, p=0·00014; and 2·07, 1·17-3·68, p=0·013, respectively), but not with hand-foot syndrome. DPYD*2A and c.2846A>T were also significantly associated with severe fluoropyrimidine-associated toxicity (adjusted RR 2·85, 95% CI 1·75-4·62, p<0·0001; and 3·02, 2·22-4·10, p<0·0001, respectively). INTERPRETATION: DPYD variants c.1679T>G and c.1236G>A/HapB3 are clinically relevant predictors of fluoropyrimidine-associated toxicity. Upfront screening for these variants, in addition to the established variants DPYD*2A and c.2846A>T, is recommended to improve the safety of patients with cancer treated with fluoropyrimidines. FUNDING: None.


Assuntos
Antimetabólitos Antineoplásicos/efeitos adversos , Antimetabólitos Antineoplásicos/farmacocinética , Di-Hidrouracila Desidrogenase (NADP)/genética , Gastroenteropatias/genética , Doenças Hematológicas/genética , Neoplasias/tratamento farmacológico , Polimorfismo Genético , Capecitabina/efeitos adversos , Capecitabina/farmacocinética , Di-Hidrouracila Desidrogenase (NADP)/metabolismo , Fluoruracila/efeitos adversos , Fluoruracila/farmacocinética , Gastroenteropatias/induzido quimicamente , Gastroenteropatias/diagnóstico , Predisposição Genética para Doença , Doenças Hematológicas/induzido quimicamente , Doenças Hematológicas/diagnóstico , Humanos , Análise Multivariada , Neoplasias/diagnóstico , Neoplasias/genética , Razão de Chances , Farmacogenética , Fenótipo , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Tegafur/efeitos adversos , Tegafur/farmacocinética
15.
Soc Sci Res ; 52: 408-21, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26004470

RESUMO

Prejudices legitimize the discrimination against groups by declaring them to be of unequal, especially of less, worth. This legitimizing power is highly relevant in social conflicts of modern societies that are governed by market-oriented value systems. However, prejudice research has yet to be linked to sociological discourses on the marketization of society. We argue that Institutional Anomie Theory (IAT), a theory originally developed to explain crime rates, offers a fruitful macro-sociological framework for a better understanding of micro-social prejudices that emerge along with processes of marketization. Extending IAT to explain prejudices in a German study based on survey data offers a first attempt to underpin our theoretical hypotheses with empirical data. Although the results need to be interpreted with due caution, they suggest that the extended IAT model can be usefully applied to explain how a marketized mentality is related to different forms of institutional integration, and how it is conducive to specific prejudices that emerge in market-dominated societies against purported economically burdening social groups.


Assuntos
Anomia (Social) , Atitude , Emigrantes e Imigrantes , Pessoas Mal Alojadas , Preconceito , Discriminação Social , Desemprego , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Crime , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Valores Sociais , Fatores Socioeconômicos , Inquéritos e Questionários , Pensamento , Populações Vulneráveis , Adulto Jovem
16.
Cell Signal ; 27(3): 652-62, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25435431

RESUMO

Loss or downregulation of the tumor-suppressor KAI1 correlates with poor cancer patient prognosis. KAI1 functions by interacting with other proteins, including integrin cell adhesion and signaling receptors. We previously showed that KAI1 physically and functionally crosstalks with the tumor-biologically relevant integrin αvß3, thereby suppressing ovarian cancer cell migration and proliferation. Interestingly, in metastases, a KAI1 splice variant had been identified, indicating poor patient prognosis. Thus, we here characterized differential effects of the two KAI1 proteins upon their cellular restoration. Opposite to KAI1, KAI1-splice reduced αvß3-mediated cell adhesion, thereby inducing cell migration. This was accompanied by elevated αvß3 levels and drastically elevated focal adhesion kinase activation, however, without any obvious colocalization with αvß3, as observed for KAI1. Moreover, codistribution of KAI1 with the cell/cell-adhesion molecule E-cadherin was abrogated in KAI1-splice. Whereas KAI1 diminished cell proliferative activity, KAI1-splice prominently enhanced cell proliferation concomitant with elevated transcription and cell-surface expression of the epidermal growth factor receptor. Thus KAI1-splice does not only counteract the tumor-suppressive actions of KAI1, but - beyond that - promotes αvß3-mediated biological functions in favor of tumor progression and metastasis.


Assuntos
Integrina alfaVbeta3/metabolismo , Proteína Kangai-1/genética , Processamento Alternativo , Caderinas/metabolismo , Adesão Celular , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Receptores ErbB/genética , Receptores ErbB/metabolismo , Feminino , Humanos , Integrina alfaVbeta3/genética , Proteína Kangai-1/metabolismo , Microscopia de Vídeo , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Regiões Promotoras Genéticas , RNA Mensageiro/metabolismo , Imagem com Lapso de Tempo
17.
Chembiochem ; 15(8): 1096-100, 2014 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-24782039

RESUMO

Bioconjugates, such as antibody-drug conjugates, have gained recent attention because of their increasing use in therapeutic and diagnostic applications. Commonly used conjugation reactions based upon chemoselective reagents exhibit a number of drawbacks: most of these reactions lack regio- and stereospecificity, thus resulting in loss of protein functionality due to random modifications. Enzymes provide an obvious solution to this problem, but the intrinsic (natural) substrate specificities of existing enzymes pose severe limitations to the kind of modifications that can be introduced. Here we describe the application of the novel trypsin variant trypsiligase for site-specific modification of the C terminus of a Fab antibody fragment via a stable peptide bond. The suitability of this designed biocatalyst was demonstrated by coupling the Her2-specific Fab to artificial functionalities of either therapeutic (PEG) or diagnostic (fluorescein) relevance. In both cases we obtained homogeneously modified Fab products bearing the artificial functionality exclusively at the desired position.


Assuntos
Fragmentos Fab das Imunoglobulinas/química , Fragmentos Fab das Imunoglobulinas/metabolismo , Tripsina/metabolismo , Anticorpos Monoclonais/química , Anticorpos Monoclonais/metabolismo , Biocatálise , Linhagem Celular Tumoral , Humanos , Estrutura Molecular , Tripsina/química
18.
PLoS One ; 8(4): e60359, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23580433

RESUMO

HTRA1 is a highly conserved serine protease which has been implicated in suppression of epithelial-to-mesenchymal-transition (EMT) and cell motility in breast cancer. Its prognostic relevance for breast cancer is unclear so far. Therefore, we evaluated the impact of HTRA1 mRNA expression on patient outcome using a cohort of 131 breast cancer patients as well as a validation cohort including 2809 publically available data sets. Additionally, we aimed at investigating for the presence of promoter hypermethylation as a mechanism for silencing the HTRA1 gene in breast tumors. HTRA1 downregulation was detected in more than 50% of the breast cancer specimens and was associated with higher tumor stage (p = 0.025). By applying Cox proportional hazard models, we observed favorable overall (OS) and disease-free survival (DFS) related to high HTRA1 expression (HR = 0.45 [CI 0.23-0.90], p = 0.023; HR = 0.55 [CI 0.32-0.94], p = 0.028, respectively), with even more pronounced impact in node-positive patients (HR = 0.21 [CI 0.07-0.63], p = 0.006; HR = 0.29 [CI 0.13-0.65], p = 0.002, respectively). Moreover, HTRA1 remained a statistically significant factor predicting DFS among established clinical parameters in the multivariable analysis. Its impact on patient outcome was independently confirmed in the validation set (for relapse-free survival (n = 2809): HR = 0.79 [CI 0.7-0.9], log-rank p = 0.0003; for OS (n = 971): HR = 0.63 [CI 0.48-0.83], log-rank p = 0.0009). In promoter analyses, we in fact detected methylation of HTRA1 in a small subset of breast cancer specimens (two out of a series of 12), and in MCF-7 breast cancer cells which exhibited 22-fold lower HTRA1 mRNA expression levels compared to unmethylated MDA-MB-231 cells. In conclusion, we show that downregulation of HTRA1 is associated with shorter patient survival, particularly in node-positive breast cancer. Since HTRA1 loss was demonstrated to induce EMT and cancer cell invasion, these patients might benefit from demethylating agents or histone deacetylase inhibitors previously reported to lead to HTRA1 upregulation, or from novel small-molecule inhibitors targeting EMT-related processes.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/mortalidade , Regulação para Baixo/genética , Serina Endopeptidases/genética , Adulto , Idoso , Sequência de Bases , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Metilação de DNA , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Serina Peptidase 1 de Requerimento de Alta Temperatura A , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Regiões Promotoras Genéticas , RNA Mensageiro/genética , Reprodutibilidade dos Testes
19.
Hum Mutat ; 32(6): E2176-88, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21618343

RESUMO

The Partner and Localizer of BRCA2 (PALB2) protein has been linked to Fanconi anemia and breast cancer predisposition. Here we present data of a comprehensive mutation screening of the PALB2 gene in 818 familial cases of breast cancer from Germany. By analyzing the entire coding region of PALB2, we found seven truncating mutations (six of them novel) in families tested negative for BRCA1/2-mutations. In addition, two novel potentially disease causing missense mutations were found. Remarkably, only one mutation reported previously in other populations, was also identified in the German population. No PALB2 mutation carriers were identified in 450 unaffected controls. Thus, our observations indicate a low prevalence of deleterious PALB2 mutations and a specific mutation profile within the German population. As PALB2-deficient tumors were shown to be sensitive to Poly(ADP-ribose) Polymerase (PARP) inhibitors, our study has implications for newly developed, favorable treatment options in familial breast cancer.


Assuntos
Neoplasias da Mama/genética , Mutação em Linhagem Germinativa , Proteínas Nucleares/genética , Proteínas Supressoras de Tumor/genética , Adulto , Proteína BRCA2/genética , Códon sem Sentido , Análise Mutacional de DNA , Proteína do Grupo de Complementação N da Anemia de Fanconi , Feminino , Predisposição Genética para Doença , Alemanha , Humanos , Pessoa de Meia-Idade , Mutação de Sentido Incorreto
20.
Clin Biochem ; 44(8-9): 722-4, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21420945

RESUMO

OBJECTIVES: Evaluation of a non-synonymous mutation associated with dihydropyrimidine dehydrogenase (DPD) deficiency. DESIGN AND METHODS: DPD enzyme analysis, mutation analysis and molecular dynamics simulations based on the 3D-model of DPD. RESULTS: The substitution Lys63Glu is likely to affect the FAD binding pocket within the DPD protein and contributes to a near-complete DPD deficiency in a patient with developmental retardation. CONCLUSIONS: Like other DPD variants attenuating FAD binding, Lys63Glu should be included in screening for DPD deficiency.


Assuntos
Deficiência da Di-Hidropirimidina Desidrogenase/urina , Di-Hidrouracila Desidrogenase (NADP)/genética , Flavina-Adenina Dinucleotídeo/metabolismo , Mutação de Sentido Incorreto/genética , Sequência de Aminoácidos , Criança , Creatinina/urina , Di-Hidrouracila Desidrogenase (NADP)/química , Di-Hidrouracila Desidrogenase (NADP)/metabolismo , Genótipo , Humanos , Masculino , Dados de Sequência Molecular , Ligação Proteica/genética , Ligação Proteica/fisiologia , Homologia de Sequência de Aminoácidos , Timina/urina , Uracila/análogos & derivados , Uracila/urina
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