Multilevel assessment of carbamazepine effects: An integrative approach using zebrafish early-life stages.

Carbamazepine (CBZ) is the most commonly used drug in epilepsy treatment, and its metabolites are commonly detected among persistent pharmaceuticals in the aquatic environment. This study aimed to investigate CBZ effects on early-life-stage zebrafish (Danio rerio) (from 2 to 168 hpf) by employing of an integrative approach linking endpoints from molecular to individual level: (i) development; (ii) locomotor activity; (iii) biochemical markers (lactate dehydrogenase, glutathione-S-transferase, acetylcholinesterase and catalase) and (iv) transcriptome analysis using microarray. A 168 h - LC50 of 73.4 mg L-1 and a 72 h - EC50 of 66.8 mg L-1 for hatching were calculated while developmental effects (oedemas and tail deformities) were observed at CBZ concentrations above 37.3 mg L-1. At the biochemical level, AChE activity proved to be the most sensitive parameter, as evidenced by its decrease across all concentrations tested (∼25% maximum reduction, LOEC (lowest observed effect concentration) < 0.6 µg L-1). Locomotor behaviour seemed to be depressed by CBZ although this effect was only evident at the highest concentration tested (50 mg L-1). Molecular analysis revealed a dose-dependent effect of CBZ on gene expression. Although only 25 genes were deregulated in organisms exposed to CBZ when compared to controls, both 0.6 and 2812 µg L-1 treatments impaired gene expression related to development (e.g. crygmxl1, org, klf2a, otos, stx16 and tob2) and the nervous system (e.g. Rtn3, Gdf10, Rtn3), while activated genes were associated with behavioural response (e.g. prlbr and taar). Altogether, our results indicate that environmentally relevant CBZ concentrations might affect biochemical and genetic traits of fish. Thus, the environmental risk of CBZ cannot be neglected, especially in a realistic scenario of constant input of domestic effluents into aquatic systems.

Aprendizagem baseada em casos clínicos no ensino de genética para medicina / Learning based on clinical cases in the teaching of genetics for medicine

Resumo Introdução: A necessidade premente de formar médicos autônomos e proativos implica novas abordagens didáticas e formas de mediar o conteúdo. Nesse contexto, a utilização de métodos ativos de ensino e aprendizagem pode incrementar o perfil do novo profissional. A Aprendizagem Baseada em Casos (ABC) é uma estratégia fundamentada na capacidade de o estudante relacionar teoria e prática com autonomia e tomada de decisão. A disciplina de genética aborda conteúdos que podem parecer distantes do cotidiano e da prática profissional futura, e, por isso, a necessidade de utilizar estratégias de ensino que facilitem a compreensão da aplicação desse conhecimento na prática médica. Objetivo: O presente trabalho teve por objetivo avaliar a ABC como abordagem pedagógica no processo de ensino-aprendizagem de genética para o curso de Medicina de uma instituição pública. Método: Aplicou-se um protocolo de método ativo composto por nove casos clínicos a 46 estudantes de Medicina da Universidade de Brasília que, posteriormente, foram divididos em nove grupos. Por meio de questionários, avaliaram-se o desempenho e as percepções em relação ao método. Os resultados quantitativos foram analisados por meio do teste t de Student. Resultado: O rendimento do trabalho em grupo foi estatisticamente maior em oito dos nove casos em comparação ao trabalho individual. A atividade foi considerada boa ou muito boa por 76% dos estudantes, e 90% mencionaram que houve aumento da motivação. Além disso, 71,4% destes demonstraram interesse em estudar mais sobre o assunto após a aula, 20% se consideraram capazes de ensinar o assunto a outras pessoas, e 42% avaliaram que acertariam todas ou a maioria das questões caso fossem submetidos a uma nova avaliação. Com relação ao trabalho em equipe, 38% relataram se sentir mais motivados. Por fim, 86% consideraram relevante ou muito relevante a discussão de casos clínicos para a formação profissional. Conclusão: Os resultados demostraram sucesso no uso do método ABC na abordagem de genética, porém apontaram que há dificuldades na utilização de métodos de ensino alternativos à aula expositiva. Apesar disso, fica explícito que a estratégia adotada pode levar à mobilização de conhecimentos prévios em situações da prática profissional.

Abstract Introduction: The pressing need to train autonomous and proactive professionals demands new ways of mediating content. In this context, the use of active teaching and learning methods can improve the profile of the new professional. Case-Based Learning (CBL) is a strategy based on the student's ability to relate theory and practice, with autonomy and decision-making. The discipline of Genetics addresses contents that may seem distant from everyday life and future professional practice, so it is necessary to use teaching strategies that facilitate the understanding of the application of this knowledge in medical practice. Objective: This study aimed to evaluate the CBL as a pedagogical approach in the teaching-learning process of Genetics for Medicine courses in a public institution. Methods: An active methodology protocol that consisted of nine clinical cases was applied to 46 medical students from Universidade de Brasília, who were later divided into nine groups. The performance and perceptions regarding the methodology were evaluated by questionnaires. Quantitative results were analyzed using Student's t test. Results: The performance of group work was statistically higher in 8 of 9 cases compared to individual work. Most students considered the activity good or very good (76%), but approximately half reported no increase in motivation. Moreover, 71.4% felt motivated to learn more about the subject after class and 20% considered they were able to teach the subject to others and 42% assessed they would get all or most of the questions correct if they were submitted to a new assessment. Regarding teamwork, 38% reported feeling more motivated. Finally, 86% considered the discussion of clinical cases relevant or very relevant for professional training. Final considerations: The results show, in general, success in the use of CBL on the study of genetic diseases but point out that there are difficulties in the use of alternative teaching methods to the lecture. Despite this, it is clear that learning based on clinical cases can lead to the mobilization of previous knowledge in situations of professional practice.

Multi-level toxicity assessment of the antidepressant venlafaxine in embryos/larvae and adults of zebrafish (Danio rerio).

The toxic effects of venlafaxine (VLX) on aquatic organisms have already been verified and therefore are a proven matter of concern. Herein, we evaluated zebrafish embryos/adults after acute exposure to VLX. Embryos/larvae were exposed to different concentrations of VLX (100-1000 mg/L; 1.33 as a dilution factor), to evaluate mortality/developmental changos and to analyze biomarkers (0.002-100 mg/L). For adults, mortality, genotoxicity, and biomarkers were assessed in five different concentrations of VLX (1-100 mg/L). The median lethal concentration (LC50-168h) was 274.1 mg/L for embryos/larvae, and >100 mg/L for adults (LC50-96h). VLX decreased the heart rate frequency and caused premature hatching and lack of equilibrium in embryos/larvae exposed to different concentrations ranging from 100 to 562.5 mg/L. The activity of acetylcholinesterase (AChE) was inhibited in larvae exposed to 1, 25 and 100 mg/L. Glutathione-S-transferase (GST) activity was reduced in both larvae and adults after exposure to different concentrations, mainly at 25 mg/L. For both larvae and adults, lactate dehydrogenase (LDH) activity increased after 100 mg/L of VLX exposure. No DNA damage was observed in peripheral erythrocytes. Exposure to VLX may cause adverse effects on zebrafish in their early and adult life stages, interfering with embryo-larval development, and can induce physiological disturbances in adults.

Co-Occurrence of Germline Genomic Variants and Copy Number Variations in Hereditary Breast and Colorectal Cancer Patients.

Hereditary Breast and Ovarian Cancer (HBOC) syndrome is an autosomal dominant disease associated with a high risk of developing breast, ovarian, and other malignancies. Lynch syndrome is caused by mutations in mismatch repair genes predisposing to colorectal and endometrial cancers, among others. A rare phenotype overlapping hereditary colorectal and breast cancer syndromes is poorly characterized. Three breast and colorectal cancer unrelated patients fulfilling clinical criteria for HBOC were tested by whole exome sequencing. A family history of colorectal cancer was reported in two patients (cases 2 and 3). Several variants and copy number variations were identified, which potentially contribute to the cancer risk or prognosis. All patients presented copy number imbalances encompassing PMS2 (two deletions and one duplication), a known gene involved in the DNA mismatch repair pathway. Two patients showed gains covering the POLE2 (cases 1 and 3), which is associated with DNA replication. Germline potentially damaging variants were found in PTCH1 (patient 3), MAT1A, and WRN (patient 2). Overall, concurrent genomic alterations were described that may increase the risk of cancer appearance in HBOC patients with breast and colorectal cancers.

DNA rare copy number alterations in Reinke's Edema

Abstract Introduction: Reinke's Edema (RE) is a laryngeal lesion related to excessive tobacco smoking, voice overuse, and laryngopharyngeal reflux. Although the risk of malignancy has been considered low in literature, RE is classified among precancerous lesions. Objectives: We investigated DNA Copy Number Alterations (CNAs) in specimens of RE and its potential association with malignant progression. Methods: We used array-based comparative genomic hybridization (aCGH, Agilent 4 × 180 K platform) to study eight RE cases. All patients were heavy tobacco users for at least 30 years, and none of them progressed to cancer in the follow-up (>8 years). Two RE presented mild dysplasia, one moderate dysplasia, and no histological alterations were found in the remaining five cases. CNAs were compared with the Database of Genomic Variants (DGV) and genes mapped on altered regions had their functions annotated. Results: Six of eight patients showed different rare copy number alterations on chromosomes 2q37.3, 4q13.1, 4q13.3, 7q11.22, 10p14, and 13q34. A gain of the whole chromosome 8 were detected in one case. Of interest, four of eight RE cases showed copy number imbalances involving genes previously described in several tumor types (RASA3, COL6A3, LINC00707, LINP1, SMR3A, and SMR3B). Conclusion: The genomic imbalances herein found in RE have the potential to contribute to the phenotype but with limited or no risk of cancer. A long-term follow-up in a large series of patients could clarify the mechanisms involved in the malignant progression of RE. Level of evidence: 4.

DNA rare copy number alterations in Reinke's Edema.

INTRODUCTION: Reinke's Edema (RE) is a laryngeal lesion related to excessive tobacco smoking, voice overuse, and laryngopharyngeal reflux. Although the risk of malignancy has been considered low in literature, RE is classified among precancerous lesions. OBJECTIVES: We investigated DNA Copy Number Alterations (CNAs) in specimens of RE and its potential association with malignant progression. METHODS: We used array-based comparative genomic hybridization (aCGH, Agilent 4 × 180 K platform) to study eight RE cases. All patients were heavy tobacco users for at least 30 years, and none of them progressed to cancer in the follow-up (>8 years). Two RE presented mild dysplasia, one moderate dysplasia, and no histological alterations were found in the remaining five cases. CNAs were compared with the Database of Genomic Variants (DGV) and genes mapped on altered regions had their functions annotated. RESULTS: Six of eight patients showed different rare copy number alterations on chromosomes 2q37.3, 4q13.1, 4q13.3, 7q11.22, 10p14, and 13q34. A gain of the whole chromosome 8 were detected in one case. Of interest, four of eight RE cases showed copy number imbalances involving genes previously described in several tumor types (RASA3, COL6A3, LINC00707, LINP1, SMR3A, and SMR3B). CONCLUSION: The genomic imbalances herein found in RE have the potential to contribute to the phenotype but with limited or no risk of cancer. A long-term follow-up in a large series of patients could clarify the mechanisms involved in the malignant progression of RE.

Epidemiological, Clinical, and Genomic Profile in Head and Neck Cancer Patients and Their Families.

Inherited cancer predisposition genes are described as risk factors in head and neck cancer (HNC) families. To explore the clinical and epidemiological data and their association with a family history of cancer, we recruited 74 patients and 164 relatives affected by cancer. The germline copy number alterations were evaluated in 18 patients using array comparative genomic hybridization. Two or more first-degree relatives with HNC, tobacco-associated tumor sites (lung, esophagus, and pancreas), or other related tumors (breast, colon, kidney, bladder, cervix, stomach carcinomas, and melanoma) were reported in 74 families. Ten index patients had no exposure to any known risk factors. Family members presented tumors of 19 topographies (30 head and neck, 26 breast, 21 colon). In first-degree relatives, siblings were frequently affected by cancer (n = 58, 13 had HNC). Breast cancer (n = 21), HNC (n = 19), and uterine carcinoma (n = 15) were commonly found in first-degree relatives and HNC in second-degree relatives (n = 11). Nineteen germline genomic imbalances were detected in 13 patients; three presented gains of WRD genes. The number of HNC patients, the degree of kinship, and the tumor types detected in each relative support the role of heredity in these families. Germline alterations may potentially contribute to cancer development.

Trypanosoma cruzi Genomic Variability: Array Comparative Genomic Hybridization Analysis of Clone and Parental Strain.

Trypanosoma cruzi, the etiological agent of Chagas disease, exhibits extensive inter- and intrastrain genetic diversity. As we have previously described, there are some genetic differences between the parental G strain and its clone D11, which was isolated by the limiting dilution method and infection of cultured mammalian cells. Electrophoretic karyotyping and Southern blot hybridization of chromosomal bands with specific markers revealed chromosome length polymorphisms of small size with additional chromosomal bands in clone D11 and the maintenance of large syntenic groups. Both G strain and clone D11 belong to the T. cruzi lineage TcI. Here, we designed intraspecific array-based comparative genomic hybridization (aCGH) to identify chromosomal regions harboring copy-number variations between clone D11 and the G strain. DNA losses were more extensive than DNA gains in clone D11. Most alterations were flanked by repeated sequences from multigene families that could be involved in the duplication and deletion events. Several rearrangements were detected by chromoblot hybridization and confirmed by aCGH. We have integrated the information of genomic sequence data obtained by aCGH to the electrophoretic karyotype, allowing the reconstruction of possible recombination events that could have generated the karyotype of clone D11. These rearrangements may be explained by unequal crossing over between sister or homologous chromatids mediated by flanking repeated sequences and unequal homologous recombination via break-induced replication. The genomic changes detected by aCGH suggest the presence of a dynamic genome that responds to environmental stress by varying the number of gene copies and generating segmental aneuploidy.

Germline Mutation in MUS81 Resulting in Impaired Protein Stability is Associated with Familial Breast and Thyroid Cancer.

Multiple primary thyroid cancer (TC) and breast cancer (BC) are commonly diagnosed, and the lifetime risk for these cancers is increased in patients with a positive family history of both TC and BC. Although this phenotype is partially explained by TP53 or PTEN mutations, a significant number of patients are negative for these alterations. We judiciously recruited patients diagnosed with BC and/or TC having a family history of these tumors and assessed their whole-exome sequencing. After variant prioritization, we selected MUS81 c.1292G>A (p.R431H) for further investigation. This variant was genotyped in a healthy population and sporadic BC/TC tissues and investigated at the protein level and cellular models. MUS81 c.1292G>A was the most frequent variant (25%) and the strongest candidate due to its function of double-strand break repair. This variant was confirmed in four relatives from two families. MUS81 p.R431H protein exhibited lower expression levels in tumors from patients positive for the germline variant, compared with wild-type BC, and normal breast and thyroid tissues. Using cell line models, we showed that c.1292G>A induced protein instability and affected DNA damage response. We suggest that MUS81 is a novel candidate involved in familial BC/TC based on its low frequency in healthy individuals and proven effect in protein stability.

Comprehensive Genomic Profiling of Androgen-Receptor-Negative Canine Prostate Cancer.

Canine carcinomas have been considered natural models for human diseases; however, the genomic profile of canine prostate cancers (PCs) has not been explored. In this study, 14 PC androgen-receptor-negative cases, 4 proliferative inflammatory atrophies (PIA), and 5 normal prostate tissues were investigated by array-based comparative genomic hybridization (aCGH). Copy number alterations (CNAs) were assessed using the Canine Genome CGH Microarray 4 × 44K (Agilent Technologies). Genes covered by recurrent CNAs were submitted to enrichment and cross-validation analysis. In addition, the expression levels of TP53, MDM2 and ZBTB4 were evaluated in an independent set of cases by qPCR. PC cases presented genomic complexity, while PIA samples had a small number of CNAs. Recurrent losses covering well-known tumor suppressor genes, such as ATM, BRCA1, CDH1, MEN1 and TP53, were found in PC. The in silico functional analysis showed several cancer-related genes associated with canonical pathways and interaction networks previously described in human PC. The MDM2, TP53, and ZBTB4 copy number alterations were translated into altered expression levels. A cross-validation analysis using The Cancer Genome Atlas (TCGA) database for human PC uncovered similarities between canine and human PCs. Androgen-receptor-negative canine PC is a complex disease characterized by high genomic instability, showing a set of genes with similar alterations to human cancer.

Molecular Expression Profile Reveals Potential Biomarkers and Therapeutic Targets in Canine Endometrial Lesions.

Cystic endometrial hyperplasia (CEH), mucometra, and pyometra are common uterine diseases in intact dogs, with pyometra being a life threatening disease. This study aimed to determine the gene expression profile of these lesions and potential biomarkers for closed-cervix pyometra, the most severe condition. Total RNA was extracted from 69 fresh endometrium samples collected from 21 healthy female dogs during diestrus, 16 CEH, 15 mucometra and 17 pyometra (eight open and nine closed-cervixes). Global gene expression was detected using the Affymetrix Canine Gene 1.0 ST Array. Unsupervised analysis revealed two clusters, one mainly composed of diestrus and CEH samples and the other by 12/15 mucometra and all pyometra samples. When comparing pyometra with other groups, 189 differentially expressed genes were detected. SLPI, PTGS2/COX2, MMP1, S100A8, S100A9 and IL8 were among the top up-regulated genes detected in pyometra, further confirmed by external expression data. Notably, a particular molecular profile in pyometra from animals previously treated with exogenous progesterone compounds was observed in comparison with pyometra from untreated dogs as well as with other groups irrespective of exogenous hormone treatment status. In addition to S100A8 and S100A9 genes, overexpression of the inflammatory cytokines IL1B, TNF and IL6 as well as LTF were detected in the pyometra from treated animals. Interestingly, closed pyometra was more frequently detected in treated dogs (64% versus 33%), with IL1B, TNF, LBP and CXCL10 among the most relevant overexpressed genes. This molecular signature associated with potential biomarkers and therapeutic targets, such as CXCL10 and COX2, should guide future clinical studies. Based on the gene expression profile we suggested that pyometra from progesterone treated dogs is a distinct molecular entity.

Alterações genômicas em pacientes e seus familiares com a síndrome do câncer colorretal hereditário / Genomic alterations in patients and their relatives with unexplained familial or early-onset colorectal cancer

O câncer colorretal (CCR) é a terceira neoplasia mais comum no mundo. Estima-se que 35% dos CCRs são hereditários, no entanto, apenas 5% destes casos são explicados por mutações patogênicas em genes de alta penetrância, A Síndrome de Lynch (SL) é a doença hereditária mais comum associada com o risco de CCR estando associada com mutações germinativas nos genes de reparo a erros de pareamento (Mismatch repair genes - MMR). Neste estudo foram avaliadas as alterações genômicas em 54 pacientes com a SL (critérios clínicos de Amsterdam ou Bethesda) e negativos para mutações patogênicas nos genes MMR (MLH1, MSH2, MSH6 e PMS2), TP53 ou CHEK2 (100delC); com o objetivo de identificar novos genes que poderiam estar associados com a predisposição ao CCR. As variações no número de cópias (Copy number variations - CNVs) foram avaliadas em todos os casos utilizando a plataforma de microarranjos (microarray) Agilent 4X180K, enquanto 26 casos também foram reanalisados com a plataforma Affymetrix CytoScan HD. Em 21 casos foram identificadas apenas CNVs comuns, enquanto 33 pacientes apresentaram 58 CNVs raras. Destas, 43 CNVs raras cobriram genes e foram detectadas em 28 pacientes. Nos casos avaliados com as ambas as plataformas foi possível validar 9 CNVs raras. A análise in silico revelou que 52 dos 81 genes afetados por CNVs raras foram associados com câncer, dos quais 26 estavam relacionados com o CCR...

Colorectal Cancer (CRC) is the third most common cancer worldwide. It is estimatedthat 35% of CRCs are hereditary. However, only 5% of these cases are explained bypathogenic mutations in high-penetrance genes. Lynch Syndrome (LS) is the mostcommon hereditary disease related to CRC risk being associated with germlinemutations in the mismatch repair genes (MMR). In this study, we evaluated genomicalterations in 54 LS patients (Amsterdam or Bethesda clinical criteria) negative forpathogenic mutations in MMR genes (MLH1, MSH2, MSH6 and PMS2), TP53 orCHEK2 (100delC), aiming to identify new genes that might be associated with CRCpredisposition. Copy number variations (CNVs) were assessed in all cases usingAgilent 4x180K microarray platform, while 26 cases were also reanalyzed byAffymetrix CytoScan HD platform. Twenty-one cases presented only commonCNVs, while 33 patients presented 58 rare CNVs. From these, 43 rare CNVs coveredgenes and were detected in 28 patients. Nine rare CNVs were validated in patientsevaluated by both platforms. In silico analysis revealed that 52 of the 81 genesaffected by rare CNVs have been associated with cancer, of these 26 were related toCRC. Among these alterations, an intronic deletion in ROBO1 gene was detected in ayoung patient with CRC with no family history of cancer. Coincidentally, identicaldeletion was found in two unrelated patients with family history of breast cancer,thus providing further evidence of the pathogenic effect of this CNV...

Genomic signatures predict poor outcome in undifferentiated pleomorphic sarcomas and leiomyosarcomas.

Undifferentiated high-grade pleomorphic sarcomas (UPSs) display aggressive clinical behavior and frequently develop local recurrence and distant metastasis. Because these sarcomas often share similar morphological patterns with other tumors, particularly leiomyosarcomas (LMSs), classification by exclusion is frequently used. In this study, array-based comparative genomic hybridization (array CGH) was used to analyze 20 UPS and 17 LMS samples from untreated patients. The LMS samples presented a lower frequency of genomic alterations compared with the UPS samples. The most frequently altered UPS regions involved gains at 20q13.33 and 7q22.1 and losses at 3p26.3. Gains at 8q24.3 and 19q13.12 and losses at 9p21.3 were frequently detected in the LMS samples. Of these regions, gains at 1q21.3, 11q12.2-q12.3, 16p11.2, and 19q13.12 were significantly associated with reduced overall survival times in LMS patients. A multivariate analysis revealed that gains at 1q21.3 were an independent prognostic marker of shorter survival times in LMS patients (HR = 13.76; P = 0.019). Although the copy number profiles of the UPS and LMS samples could not be distinguished using unsupervised hierarchical clustering analysis, one of the three clusters presented cases associated with poor prognostic outcome (P = 0.022). A relative copy number analysis for the ARNT, SLC27A3, and PBXIP1 genes was performed using quantitative real-time PCR in 11 LMS and 16 UPS samples. Gains at 1q21-q22 were observed in both tumor types, particularly in the UPS samples. These findings provide strong evidence for the existence of a genomic signature to predict poor outcome in a subset of UPS and LMS patients.

Cortactin is associated with perineural invasion in the deep invasive front area of laryngeal carcinomas.

The cortactin gene, mapped at 11q13, has been associated with an aggressive clinical course in many cancers because of its function of invasiveness. This study evaluated CTTN protein and its prognostic value in the deep invasive front and superficial areas of laryngeal squamous cell carcinomas. The transcript expression levels were evaluated in a subset of cases. Overexpression of CTTN cytoplasmatic protein (80% of cases in both the deep invasive front and superficial areas) and transcript (30% of samples) was detected in a significant number of cases. In more than 20% of cases, observation verified membrane immunostaining in the deep invasive front and superficial areas. Perineural invasion was significantly associated with N stage and recurrence (P = .0058 and P = .0037, respectively). Higher protein expression levels were correlated with perineural invasion (P = .004) in deep invasive front cells, suggesting that this area should be considered a prognostic tool in laryngeal carcinomas. Although most cases had moderate to strong CTTN expression on the tumor surface, 2 sets of cases revealed a differential expression pattern in the deep invasive front. A group of cases with absent to weak expression of CTTN in the deep invasive front showed good prognosis parameters, and a second group with moderate to strong expression of CTTN were associated with an unfavorable prognosis, suggesting an association with worse outcome. Taken together, these results suggest that the deep invasive front might be considered a grading system in laryngeal carcinomas and that cortactin is a putative marker of worse outcome in the deep invasive front of laryngeal carcinomas.