Tissue aluminum concentration does not affect the genomic stability of ERBB2, C-MYC, and CCND1 genes in breast cancer.

It has long been hypothesized that body tissue uptake of aluminum may have biological implications in breast cancer. In vitro and in vivo studies have shown that aluminum may trigger genomic instability by interfering with DNA strands. The objective of this study was to examine the relationship between aluminum concentrations in the peripheral and central areas of breast tumors with the instability of three key genes in breast cancer, ERBB2, C-MYC, and CCND1 and aneuploidy of the chromosomes harboring these genes. Tissue samples of 118 women treated for breast cancer were obtained. Evaluation of aluminum content was carried out using graphite furnace atomic absorption spectrometry. A tissue microarray slide containing the tumor samples was used in FISH assays to assess ERBB2, C-MYC, and CCND1 expressions as well as the statuses of their respective chromosomes 17, 8, and 11. Clinicopathological data were obtained from patient's records. Aluminum levels of >2.0 mg/kg were found in 20.3 and 22.1% of the central and peripheral breast tumor areas, respectively. Amplification and/or aneuploid-positive statuses for ERBB2/CEP17, C-MYC/CEP8, and CCND1/CEP11 were detected in 24, 36.7, and 29.3% of the tumors, respectively. We found that aluminum concentration was not related to these altered gene statuses. Our findings suggest that aluminum concentration does not affect genomic stability in breast tissues. Tissue microenvironment modifications, due to the presence of aluminum compounds, seem more appealing as a possible target for future studies to determine the implications of aluminum in breast carcinogenesis.

Aluminum concentrations in central and peripheral areas of malignant breast lesions do not differ from those in normal breast tissues.

BACKGROUND: Aluminum is used in a wide range of applications and is a potential environmental hazard. The known genotoxic effects of aluminum might play a role in the development of breast cancer. However, the data currently available on the subject are not sufficient to establish a causal relationship between aluminum exposure and the augmented risk of developing breast cancer. To achieve maximum sensitivity and specificity in the determination of aluminum levels, we have developed a detection protocol using graphite furnace atomic absorption spectrometry (GFAAS). The objective of the present study was to compare the aluminum levels in the central and peripheral areas of breast carcinomas with those in the adjacent normal breast tissues, and to identify patient and/or tumor characteristics associated with these aluminum levels. METHODS: A total of 176 patients with breast cancer were included in the study. Samples from the central and peripheral areas of their tumors were obtained, as well as from the surrounding normal breast tissue. Aluminum quantification was performed using GFAAS. RESULTS: The average (mean ± SD) aluminum concentrations were as follows: central area, 1.88 ± 3.60 mg/kg; peripheral area, 2.10 ± 5.67 mg/kg; and normal area, 1.68 ± 11.1 mg/kg. Overall and two-by-two comparisons of the aluminum concentrations in these areas indicated no significant differences. We detected a positive relationship between aluminum levels in the peripheral areas of the tumors, age and menopausal status of the patients (P = .02). CONCLUSIONS: Using a sensitive quantification technique we detected similar aluminum concentrations in the central and peripheral regions of breast tumors, and in normal tissues. In addition, we did not detect significant differences in aluminum concentrations as related to the location of the breast tumor within the breast, or to other relevant tumor features such as stage, size and steroid receptor status. The next logical step is the assessment of whether the aluminum concentration is related to the key genomic abnormalities associated with breast carcinogenesis.

[Subfertility phenotype, chromosome polymorphism and conception failures]. / Fenótipo de subfertilidade, polimorfismos cromossômicos e falhas de concepção.

PURPOSE: To evaluate the prevalence of cytogenetic alterations and chromosomic polymorphism in couples with a subfertility phenotype in a Brazilian population. METHODS: Karyotype analysis through G and C banding of 1,236 individuals who presented the subfertility phenotype, from two different centers (public and private) were included in the study. These patients were classified in two sub-groups: one with two or more gestational consecutive losses or not and the o with, at least, one gestacional loss or absence of conception. Karyotype results were evaluated in different groups and frequencies were calculated. Statistical analyses were carried out through Fisher's exact test and Odds Ratio analysis. RESULTS: Approximately 25% of the cases presented abnormal karyotype results, including numerical and structural alterations and also polymorphic variants. In both centers, the prevalence of polymorphic variants was 8.9 and 3.8%, respectively. CONCLUSIONS: There was no significant difference between the prevalence of polymorphic variants and other abnormalities in individuals with or without previous history of reproductive loss. The results of the present study reinforce the need of adequate disclosure of complete cytogenetic information in the karyotype results, with specific attention in relation to the polymorphic variants.

Fenótipo de subfertilidade, polimorfismos cromossômicos e falhas de concepção / Subfertility phenotype, chromosome polymorphism and conception failures

OBJETIVO: avaliar a prevalência de alterações citogenéticas e polimorfismos cromossômicos em casais com fenótipo de subfertilidade em uma população brasileira. MÉTODOS: foram avaliados 1.236 cariótipos de casais com fenótipo de subfertilidade de dois diferentes centros (público e privado). Esses pacientes foram classificados em dois subgrupos: um com duas ou mais perdas gestacionais, consecutivas ou não, e outro com, ao menos, uma perda gestacional ou ausência de concepção. Os cariótipos foram obtidos com bandamento convencional G e C. As anomalias citogenéticas foram agrupadas e as frequências calculadas segundo a classificação dos pacientes. Quando aplicável, os testes estatísticos de Fisher e análise de Odds Ratio foram empregados. RESULTADOS: aproximadamente 25 por cento de todos os casos apresentaram cariótipo anormal, incluindo alterações numéricas e estruturais e também variantes polimórficas. Nos dois diferentes centros, a prevalência de variantes polimórficas diferiu, sendo de 8,9 e 3,8 por cento, respectivamente. CONCLUSÃO: não houve diferença significativa entre a predominância de variantes polimórficas e outras alterações nos indivíduos com ou sem história de perda reprodutiva. Os resultados do presente estudo reforçam a necessidade da adequada divulgação da informação citogenética completa nos resultados de cariótipo, com atenção específica em relação às variantes polimórficas.

PURPOSE: to evaluate the prevalence of cytogenetic alterations and chromosomic polymorphism in couples with a subfertility phenotype in a Brazilian population. METHODS: karyotype analysis through G and C banding of 1,236 individuals who presented the subfertility phenotype, from two different centers (public and private) were included in the study. These patients were classified in two sub-groups: one with two or more gestational consecutive losses or not and the o with, at least, one gestacional loss or absence of conception. Karyotype results were evaluated in different groups and frequencies were calculated. Statistical analyses were carried out through Fisher's exact test and Odds Ratio analysis. RESULTS: approximately 25 percent of the cases presented abnormal karyotype results, including numerical and structural alterations and also polymorphic variants. In both centers, the prevalence of polymorphic variants was 8.9 and 3.8 percent, respectively. CONCLUSIONS: there was no significant difference between the prevalence of polymorphic variants and other abnormalities in individuals with or without previous history of reproductive loss. The results of the present study reinforce the need of adequate disclosure of complete cytogenetic information in the karyotype results, with specific attention in relation to the polymorphic variants.

Genomic imbalances detected through array CGH in fetuses with holoprosencephaly.

OBJECTIVE: Holoprosencephaly (HPE) is heterogeneous in pathogenesis, integrating genetic susceptibility with the influence of environmental factors. Submicroscopic aberrations may contribute to the etiology of HPE. Our aim was to report the molecular analysis of 4 fetuses with HPE and normal metaphase karyotype. METHOD: A whole genome BAC-array based Comparative Genomic Hybridization (array CGH) was carried out in fetal blood samples. All potential cytogenetic alterations detected on the arrays were matched against the known copy number variations databases. RESULTS: The array CGH analysis showed copy number gains and losses in all cases. We found a recurrent deletion in 15q14 (clone RP11-23J11) and in 15q22 (clone RP11-537k8) in 2 out 4 cases analyzed. We also observed submicroscopic gain in 6p21 in 3 out of 4 fetuses in nearby clones. All these regions were tested in known databases and no copy number variations have been described for them. CONCLUSION: This is the first report of molecular characterization through a whole genome microarray CGH of fetuses with HPE. Our results may contribute to verify the effectiveness and applicability of the molecular technique of array CGH for prenatal diagnosis purposes, and contributing to the knowledge of the submicroscopic genomic instability characterization of HPE fetuses.

Genomic imbalances detected through array CGH in fetuses with holoprosencephaly / Instabilidades genômicas detectadas através de array CGH em fetos com holoprosencefalia

OBJECTIVE: Holoprosencephaly (HPE) is heterogeneous in pathogenesis, integrating genetic susceptibility with the influence of environmental factors. Submicroscopic aberrations may contribute to the etiology of HPE. Our aim was to report the molecular analysis of 4 fetuses with HPE and normal metaphase karyotype. METHOD: A whole genome BAC-array based Comparative Genomic Hybridization (array CGH) was carried out in fetal blood samples. All potential cytogenetic alterations detected on the arrays were matched against the known copy number variations databases. RESULTS: The array CGH analysis showed copy number gains and losses in all cases. We found a recurrent deletion in 15q14 (clone RP11-23J11) and in 15q22 (clone RP11-537k8) in 2 out 4 cases analyzed. We also observed submicroscopic gain in 6p21 in 3 out of 4 fetuses in nearby clones. All these regions were tested in known databases and no copy number variations have been described for them. CONCLUSION: This is the first report of molecular characterization through a whole genome microarray CGH of fetuses with HPE. Our results may contribute to verify the effectiveness and applicability of the molecular technique of array CGH for prenatal diagnosis purposes, and contributing to the knowledge of the submicroscopic genomic instability characterization of HPE fetuses.

OBJETIVO: Holoprosencefalia (HPE) é uma malformação heterogênea na patogênese, integrando a suscetibilidade genética com a influência de fatores ambientais. Aberrações submicroscópicas podem contribuir para a etiologia da HPE. Nosso objetivo foi relatar a análise molecular de 4 fetos com HPE e cariótipo normal. MÉTODO: Foi realizado um estudo descritivo prospectivo dos achados da técnica de hibridação genômica comparativa baseada em microarranjos utilizando BAC clones de ampla cobertura genômica (BAC-array CGH) em amostras sanguíneas de fetos portadores de holoprosencefalia e com cromossomos numericamente normais ao bandamento G. Todas as potenciais alterações citogenéticas detectadas foram comparadas com bancos de dados com variações do número de cópias conhecidas. RESULTADOS: A análise de array CGH evidenciou ganhos e perdas do número de cópias em todos os 4 casos. Foram encontradas deleções recorrentes em 15q14 (clone RP11-23J11) e em 15q22 (clone RP11-537k8) em 2 dos 4 casos analisados. Observou-se em 3 fetos ganho genômico na região 6p21 em clones próximos. Todas estas regiões não apresentaram variações do número de cópias descritas em bancos de dados conhecidos. CONCLUSÃO: Este é o primeiro relato de caracterização molecular através de um microarray CGH de fetos com HPE. Nossos resultados podem contribuir para verificar a eficácia e aplicabilidade da técnica molecular de array CGH para fins de diagnóstico pré-natal, contribuindo para o conhecimento da caracterização de instabilidades genômicas submicroscópicas de fetos com HPE.

[ErbB-2 expression and hormone receptor status in areas of transition from in situ to invasive ductal breast carcinoma]. / Expressão da proteína erbB-2 e dos receptores de hormônios na transição das regiões in situ para invasora de tumores da mama.

PURPOSE: to evaluate the expression of erbB-2 and of the estrogen and progesterone (ER/P) hormonal receptors in the transition regions between the in situ and the invasive fractions of ductal breast neoplasia (ISDC and IDC, respectively). METHODS: Eighty-five cases of breast neoplasia, containing contiguous ISDC and IDC areas, were selected. Histological specimens from the ISDC and the IDC areas were obtained through the tissue microarray (TMA) technique. The erbB-2 and the ER/PR expressions were evaluated through conventional immunohistochemistry. The McNemar's test was used for the comparative analysis of the expressions of erbB-2 protein and the ER/PR in the in situ and invasive regions of the tumors. The confidence intervals were set to 5% (p=0.05). Intraclass correlation coefficients (ICC) were calculated to assess the cross-tabulation agreement of the erbB-2 and the ER/PR expression in the ISDC and the IDC areas. RESULTS: the erbB-2 expression has not differed between the ISDC and the IDC areas (p=0.38). Comparing the two areas in each case, there was agreement in the expression of erbB-2 (ICC=0.64), PR (ICC=0.71) and ER (ICC=0.64). Restricting the analysis to tumors with the in situ component harboring necrosis (comedo), the ICC for erbB-2 was 0.4, compared to 0.6 for the whole sample. In this select group, the ICC for PR/ER did not differ substantially from those obtained with the complete dataset: as for the ER, ICC=0.7 (versus 0.7 for the entire sample) and for PR, ICC=0.7 (versus 0.6 for the entire sample). CONCLUSIONS: our findings suggest that the erbB-2 and the ER/PR expressions do not differ in the contiguous in situ and invasive components of breast ductal tumors.

Expressão da proteína erbB-2 e dos receptores de hormônios na transição das regiões in situ para invasora de tumores da mama / ErbB-2 expression and hormone receptor status in areas of transition from in situ to invasive ductal breast carcinoma

OBJETIVOS: avaliar a expressão de erbB-2 e dos receptores hormonais para estrógeno e progesterona (RE/RP) nas regiões de transição entre as frações in situ e invasoras de neoplasias ductais da mama (CDIS e CDI, respectivamente). MÉTODOS: oitenta e cinco casos de neoplasias mamárias, contendo regiões contíguas de CDIS e CDI, foram selecionados. Espécimes histológicos das áreas de CDIS e de CDI foram obtidos através da técnica de tissue microarray (TMA). As expressões da erbB-2 e dos RE/RP foram avaliadas por meio de imunoistoquímica convencional. A comparação da expressão da erbB-2 e dos RE/RP nas frações in situ e invasoras da mama foi realizada com emprego do teste de McNemar. Os intervalos de confiança foram determinados em 5 por cento (p=0,05). Foram calculados coeficientes de correlação intraclasse (ICC) para avaliar a concordância na tabulação cruzada da expressão de erbB-2 e RE/RP nas frações de CDIS e CDI. RESULTADOS: a expressão da erbB-2 não diferiu entre as áreas de CDIS e CDI (p=0,38). Comparando caso a caso suas áreas de CDIS e CDI, houve boa concordância na expressão da erbB-2 (coeficiente de correlação intraclasse, ICC=0,64), dos RP (ICC = 0,71) e dos RE (ICC = 0,64). Considerando apenas tumores cujo componente in situ apresentasse áreas de necrose (comedo), o ICC para erbB-2 foi de 0,4, comparado a 0,6 no conjunto completo de casos. Os ICC não diferiram substancialmente daqueles obtidos com o conjunto completo de espécimes em relação aos RE/RP: para RE, ICC=0,7 (versus 0,7 no conjunto completo), e para RP, ICC=0,7 (versus 0,6 no conjunto completo). CONCLUSÕES: nossos achados sugerem que as expressões de erbB-2 e RE/RP não diferem nos componentes contíguos in situ e invasivo em tumores ductais da mama.

PURPOSE: to evaluate the expression of erbB-2 and of the estrogen and progesterone (ER/P) hormonal receptors in the transition regions between the in situ and the invasive fractions of ductal breast neoplasia (ISDC and IDC, respectively). METHODS: Eighty-five cases of breast neoplasia, containing contiguous ISDC and IDC areas, were selected. Histological specimens from the ISDC and the IDC areas were obtained through the tissue microarray (TMA) technique. The erbB-2 and the ER/PR expressions were evaluated through conventional immunohistochemistry. The McNemar's test was used for the comparative analysis of the expressions of erbB-2 protein and the ER/PR in the in situ and invasive regions of the tumors. The confidence intervals were set to 5 percent (p=0.05). Intraclass correlation coefficients (ICC) were calculated to assess the cross-tabulation agreement of the erbB-2 and the ER/PR expression in the ISDC and the IDC areas. RESULTS: the erbB-2 expression has not differed between the ISDC and the IDC areas (p=0.38). Comparing the two areas in each case, there was agreement in the expression of erbB-2 (ICC=0.64), PR (ICC=0.71) and ER (ICC=0.64). Restricting the analysis to tumors with the in situ component harboring necrosis (comedo), the ICC for erbB-2 was 0.4, compared to 0.6 for the whole sample. In this select group, the ICC for PR/ER did not differ substantially from those obtained with the complete dataset: as for the ER, ICC=0.7 (versus 0.7 for the entire sample) and for PR, ICC=0.7 (versus 0.6 for the entire sample). CONCLUSIONS: our findings suggest that the erbB-2 and the ER/PR expressions do not differ in the contiguous in situ and invasive components of breast ductal tumors.

Prenatal genomic profiling of abdominal wall defects through comparative genomic hybridization: perspectives for a new diagnostic tool.

OBJECTIVES: To describe the molecular analysis through comparative genomic hybridization (CGH) of fetuses with gastroschisis, and to observe if this technique could improve the resolution of the conventional cytogenetic techniques. METHODS: Amniotic analysis of fetuses with gastroschisis, using both conventional (G-banding) and molecular (CGH) cytogenetics assays. RESULTS: All of the seven fetuses studied displayed a normal G-band karyotype. Six fetuses displayed a normal disomic profile through CGH and one sample has displayed ish cgh enh 3q26-->qter result (ICSN). The fetus with this imbalance of chromosome 3 was re-classified as a ruptured omphalocele, instead of gastroschisis, after birth. CONCLUSIONS: The molecular investigation through CGH technique can improve the resolution of the conventional karyotye analysis in cases of abdominal wall defects.

Analysis of BRCA1 and BRCA2 mutations in Brazilian breast cancer patients with positive family history

CONTEXTO E OBJETIVO: BRCA1 e BRCA2 são os dois principais genes de susceptibilidade ao câncer de mama hereditário e a prevalência de mutações nestes genes não é conhecida em mulheres brasileiras. O objetivo do estudo foi detectar mutações de BRCA1 e BRCA2, contribuindo para estabelecer um perfil dos carcinomas de mama hereditários na população brasileira. TIPO DE ESTUDO E LOCAL: Estudo transversal, no Centro de Atenção Integral à Saúde da Mulher, Universidade Estadual de Campinas, Brasil, e no Instituto de Patologia e Imunologia Molecular da Universidade do Porto, Portugal. MÉTODOS: 31 pacientes com carcinoma de mama e história familiar (critérios do Breast Cancer Linkage Consortium), foram estudadas e tiveram DNA extraído do sangue periférico. Single strand conformation polymorphism (SSCP) foi empregado para analisar os exons 2, 3, 5, e 20 do BRCA1. Aqueles casos que mostraram produtos de reação da polimerase em cadeia (PCR) com bandas anormais foram seqüenciados. Entretanto, o exon 11 do BRCA1 e exons 10 e 11 do BRCA2 foram diretamente para o seqüenciamento. RESULTADOS: Foram identificadas quatro mutações, sendo uma mutação no BRCA1 e três no BRCA2. A mutação no BRCA1 é do tipo frameshift, no exon 20: 5382 insC. Duas mutações encontradas no BRCA2 são do tipo nonsense localizadas no exon 11: S2219X e uma do tipo unclassified variant localizada no exon 11: C1290Y. CONCLUSAO: A prevalência de mutações de BRCA1 e BRCA2 encontradas para mulheres com câncer de mama e história familiar de câncer de mama foi de 13 por cento (4/31). Estudos mais amplos são necessários para estabelecer o significado dessas mutações na população brasileira.

Analysis of BRCA1 and BRCA2 mutations in Brazilian breast cancer patients with positive family history.

CONTEXT AND OBJECTIVE: BRCA1 and BRCA2 are the two principal hereditary breast cancer susceptibility genes, and the prevalence of their mutations among Brazilian women is unknown. The objective was to detect BRCA1 and BRCA2 mutations in Brazilian patients with breast cancer, so as to establish genetic profiles. DESIGN AND SETTING: Cross-sectional study, in Centro de Atenção Integral à Saúde da Mulher, Universidade Estadual de Campinas, Brazil, and Institute of Pathology and Molecular Immunology, University of Porto, Portugal. METHODS: Thirty-one breast cancer patients with positive family history (criteria from the Breast Cancer Linkage Consortium) were studied, and genomic DNA was extracted from peripheral blood. Single-strand conformation polymorphism was used for the analysis of exons 2, 3, 5, and 20 of BRCA1. Cases showing PCR products with abnormal bands were sequenced. Exon 11 of BRCA1 and exons 10 and 11 of BRCA2 were directly sequenced in both directions. RESULTS: Four mutations were detected: one in BRCA1 and three in BRCA2. The BRCA1 mutation is a frameshift located at codon 1756 of exon 20: 5382 ins C. Two BRCA2 mutations were nonsense mutations located at exon 11: S2219X and the other was an unclassified variant located at exon 11: C1 290Y. CONCLUSION: The BRCA1 or BRCA2 mutation prevalence found among women with breast cancer and such family history was 13% (4/31). Larger studies are needed to establish the significance of BRCA mutations among Brazilian women and the prevalence of specific mutations.