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Background: Distinct N-acetyltransferase 2 (NAT2) slow acetylators genotypes have been associated with a higher risk to develop anti-tuberculosis drug-induced hepatotoxicity (DIH). However, studies have not pointed the relevance of different acetylation phenotypes presented by homozygotes and compound heterozygotes slow acetylators on a clinical basis., Objectives: This study aimed to investigate the association between NAT2 genotypes and the risk of developing DIH in Brazilian patients undergoing tuberculosis treatment, focusing on the discrimination of homozygotes and compound heterozygotes slow acetylators., Methods/findings: The frequency of NAT2 genotypes was analysed by DNA sequencing in 162 patients undergoing tuberculosis therapy. The mutation analyses revealed 15 variants, plus two new NAT2 mutations, that computational simulations predicted to cause structural perturbations in the protein. The multivariate statistical analysis revealed that carriers of NAT2*5/*5 slow acetylator genotype presented a higher risk of developing anti-tuberculosis DIH, on a clinical basis, when compared to the compound heterozygotes presenting NAT2*5 and any other slow acetylator haplotype [aOR 4.97, 95% confidence interval (CI) 1.47-16.82, p = 0.01]., Conclusion: These findings suggest that patients with TB diagnosis who present the NAT2*5B/*5B genotype should be properly identified and more carefully monitored until treatment outcome in order to prevent the occurrence of anti-tuberculosis DIH.

TP53 and PGAM1 genes play a key role in glycolysis which is an essential metabolic pathway of cancer cells for obtaining energy. The purpose of this work was to evaluate PGAM1 and TP53 mRNA expressions in canine mammary carcinomas (CMC) and to correlate them with animal data and tumour histological features. None of the nine samples analysed revealed PGAM1 DNA sequence variations. PGAM1 and TP53 RNA expressions from 21 CMC were analysed using a one-step reverse transcription-PCR kit and its platform system. Most CMC samples had low levels of PGAM1 mRNA (71.5%) and normal expression of TP53 mRNA (95.2%). Our results suggest a different feature of the Warburg effect on canine mammary cancer cells compared to human cells.

The ABCB1 gene encodes the P-glycoprotein (P-gp) which regulates distribution and bioavailability of many endogenous and exogenous substrates, acting as a cellular mechanism of protection against these substances. Some studies have shown evidence that P-gp is related to carcinogenesis. In this study, we performed PCR and direct sequencing of ABCB1 exons 9 and 26 in 47 tissue DNA samples from canine mammary tumors. A statistically significant correlation between distinct canine breeds and the frequency of ABCB1 polymorphisms (c.985T > A and c.3442A > G SNP in ABCB1exons 9 and 26, respectively) was observed (P = 0.0015). In contrast, the TNM clinical staging, age, histological type and grade, as well as other histopathological characteristics, did not present statistically significant difference in relation to one or both SNP found in exons 9 and 26. These findings raise questions about the role of the canine ABCB1 polymorphisms in the development of mammary tumors, since the Poodle breed, which is the most common dog breed affected by mammary tumors in Brazil, presented the highest frequency of these variants. Notwithstanding, additional studies comprising a number of samples expressing the ABCB1 gene from healthy dogs, with advanced age and from different breeds, will be necessary to confirm the association of ABCB1polymorphisms and the development of mammary tumors., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The aim of this study was to evaluate the immunoexpression of HER-2 in gastric cells of cats infected with Non H. pylori Helicobacter (NHPH) and to investigate an association with the presence of inflammatory infiltrate. Forty-eight paraffin-embedded gastric samples were retrieved from the archives of the Veterinary Anatomic Pathology Laboratory that had previously been shown to be positive for NHPH with the rapid urease test and cytology. Infection by NHPH was confirmed by histopathology using the Warthin-Starry staining. Hematoxylin-eosin stained sections were reviewed to evaluate inflammatory cell infiltrates. Immunohistochemical analysis was done using anti- H. pylori antibody and anti-HER-2 antibody. Molecular analysis was performed by PCR to confirm the presence of Helicobacter. Statistical analysis was performed to determine whether there was an association between the presence of H. Heilmannii and HER-2 expression in gastric samples. All samples were positive for NHPH, by immunohistochemistry, and confirmed by PCR as H. Heilmannii. On histopathologic analysis, 56,3% of the samples had lymphocytes and plasma cells infiltrates, 52,1% of which were mild and 4,2% moderate. The intensity of the inflammatory infiltrate in the gastric mucosa was significantly greater in the complete plasma membrane of parietal cells of gastric glands that had greater HER-2 immunoexpression (p = 0.0001). A statistically significant association (p = 0.007) between the H. Heilmannii infection score and the expression of HER-2 in the lateral membrane of gastric surface cells was observed. HER-2 expression may be increased in feline gastric cells infected by H. Heilmannii and in parietal cells of gastric glands with an increased inflammatory infiltrate., (Copyright © 2019 Elsevier GmbH. All rights reserved.)

The canine BRCA2 is a tumor supressor gene which encodes the BRCA2 protein, involved in DNA repair through interaction with the RAD51 recombinase. This process is mediated by eigth BRC repeats that are encoded by BRCA2 exon 11. Two variants corresponding to human mutations in human BRC3 repeat have been reported in canine BRC3 repeat. In addition, other variants have also been described in canine BRCA2 exon 11. Considering the importance of polymorphisms in human BRCA2 to breast cancer development, this study aimed to investigate the frequency of variants in BRCA2 exon 11 in 48 blood and tissue DNA samples from bitches with canine mammary tumors (CMT), as well as, to analyze tumor stage and histopathological features. Seven Single Nucleotide Polymorphisms (SNPs) were identified, three of which were evaluated as possibily or probably deleterious variant. Interestingly, almost all the 22 mammary tumors (except one) which presented a clinical staging equal to or greater than III carried at least one mutant allele of these three variants. Besides that, no statistically significant correlation was observed between any of the reported SNPs in heterozygosis or homozygosis and either dogs data (such as breed, age or disease stage) or mammary tumors histopathological characteristics. A total of 97.9% of bitches had one to three polymorphisms of the seven identified in this study, which suggests a possibly correlation between the canine BRCA2 exon 11 polymorphisms and mammary carcinogenesis., (© 2018 John Wiley & Sons Ltd.)

The aim of this study was to look for mutations in the equine ACTN3 gene and to identify sequence variants that might be associated with the phenotype and performance of Brazilian sport horses training for events in a tropical climate. Among 17 such horses direct DNA sequencing and mutation analysis of the exon 15 and the intron-exon boundaries of ACTN3 revealed 2 new sequence variants in the ACTN3 intron 14-15, designated c.1681-86G > A and c.1681-129delA. Wild-type/deletion heterozygotes (A/del) had a lower mean subcutaneous fat layer in the region of the gluteus medius, as measured by ultrasonography, than the del/del homozygotes; the correlation was significant ( P = 0.017). This single base-pair deletion in ACTN3 intron 14-15 may have resulted in metabolic changes that led to increased deposition of body fat in the homozygous state. However, neither sequence variant was correlated with the time to fatigue in a test on a high-speed treadmill with an incremental-speed protocol.

Polymorphisms in MSTN have previously been associated with equine performance. Therefore, the aim of this study was to identify variants in MSTN intron 1 in 16 Brazilian Sport Horses selected for competition in eventing and their possible effects of selection on performance. Among the nine variants identified, eight had already been reported in previous studies or genomic databases, although they showed differences in frequencies when compared with other horse breeds. Moreover, a new mutation was identified in two horses, both in heterozygous form. Considering the absence of molecular studies in this valuable Brazilian breed, these findings represent an important contribution to the characterization of its genetic profile and may possibly aid in further genotype-phenotype association studies.

The protein p53 is considered to be one of the most important tumor suppressor factors. Despite this importance, a potential association between TP53 messenger (m)RNA levels and tumor aggressiveness has not been well defined in animal cancer. We assessed and correlated TP53 gene expression in 40 canine mammary carcinomas with histologic grade, tumor size, and aggressiveness. The tumors were subjected to histologic analysis and the TP53 mRNA levels determined by RT-rtPCR. Statistical analysis revealed no correlation between levels of TP53 mRNA and tumor aggressiveness ( r = 0.00) or tumor growth ( r = 0.06). Histologic grades ( r = 0.17) and mitosis count ( r = 0.12) showed a weak correlation with TP53 mRNA expression levels. These findings are consistent with molecular studies that revealed heterogeneous expression of TP53 in canine and human mammary tumors. Hence, TP53 gene expression alone cannot be considered a marker for tumor aggressiveness in canine mammary carcinomas.

Tuberculosis (TB) is still a major health concern and side-effects related to the treatment, especially drug-induced hepatotoxicity (DIH), should be better investigated. In the present study, a possible association between anti-TB DIH and cigarette smoking, N-acetyltransferase 2 (NAT2), Cytochrome P450 2E1 (CYP2E1) and Cytochrome P450 3A4 (CYP3A4) genotypes was studied in 131 TB Brazilian patients. The NAT2 and CYP3A4 genetic polymorphisms were determined using a polymerase chain reaction (PCR) direct sequencing approach and genetic polymorphisms of CYP2E1 gene were determined by restriction fragment length polymorphism (RFLP). The risk of anti-TB DIH was lower in rapid/intermediate acetylators when compared to slow acetylators (OR: 0.34, CI 95: 0.16-0.71; p < 0.01). A decreased risk of developing anti-TB DIH was also observed in active smokers when compared to non-smokers (OR: 0.28, 95 CI: 0.11-0.64; p < 0.01). Significant association between CYP3A4 genotypes and hepatotoxicity was not observed, as well as between CYP2E1 genotype and hepatotoxicity, whose frequency of patients with wild homozygous was more prevalent. The anti-TB drugs interactions with smoking on hepatotoxicity, as well as the NAT2 phenotype, may require to adjust therapeutic regimen dosages or alarm in case of adverse event developments., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Holoprosencephaly (HPE) is a spectrum of brain and facial malformations primarily reflecting genetic factors, such as chromosomal abnormalities and gene mutations. Here, we present a clinical and molecular analysis of 195 probands with HPE or microforms; approximately 72% of the patients were derived from the Latin American Collaborative Study of Congenital Malformations (ECLAMC), and 82% of the patients were newborns. Alobar HPE was the predominant brain defect in almost all facial defect categories, except for patients without oral cleft and median or lateral oral clefts. Ethmocephaly, cebocephaly, and premaxillary agenesis were primarily observed among female patients. Premaxillary agenesis occurred in six of the nine diabetic mothers. Recurrence of HPE or microform was approximately 19%. The frequency of microdeletions, detected using Multiplex Ligation-dependant Probe Amplification (MLPA) was 17% in patients with a normal karyotype. Cytogenetics or QF-PCR analyses revealed chromosomal anomalies in 27% of the probands. Mutational analyses in genes SHH, ZIC2, SIX3 and TGIF were performed in 119 patients, revealing eight mutations in SHH, two mutations in SIX3 and two mutations in ZIC2. Thus, a detailed clinical description of new HPE cases with identified genetic anomalies might establish genotypic and phenotypic correlations and contribute to the development of additional strategies for the analysis of new cases.

What Is Known and Objective: Anti-tuberculosis drugs (ATD), although highly effective, often cause liver injury. Glutathione S-transferases (GST) play a crucial protective role in the detoxifying mechanisms of drugs. Several studies have investigated the genetic null variants of GSTM1 and GSTT1 as possible risk factors for ATD-induced liver injury; however, those findings are inconsistent. We investigated GSTM1 and GSTT1 null genotypes in Brazilian patients with tuberculosis (TB), adjusting for other possible predictors of ATD-induced liver injury., Methods: This was a prospective cohort study with patients who were treated for TB from 2006 to 2011. GSTM1 and GSTT1 gene deletions were analysed from genomic DNA by polymerase chain reaction (PCR). Demographic, clinical and laboratory data were extracted from medical records and possible predictors of liver injury were evaluated., Results and Discussion: This study enrolled 177 patients. Anti-tuberculosis drugs-induced liver injury incidence was 33.3%. Hepatitis B infection (HBV) and increased alanine aminotransferase (ALT) baseline were significant predictors. Neither GSTM1 nor GSTT1 null genotypes were associated with ATD-induced liver injury; nevertheless, the comparison among four different liver toxicity grades showed that GSTM1 non-null genotype was significant more frequent among the higher grades of liver toxicity., What Is New and Conclusion: GSTM1 and GSTT1 null genotypes do not seem to play important roles in ATD-induced liver injury in Brazilians. However, there was evidence that GSTM1 polymorphisms were possibly related to the intensity of toxicity. Active HBV and initial high ALT could predict ATD-induced liver injury., (© 2012 Blackwell Publishing Ltd.)

CYP3A4 is involved in tuberculosis (TB) and human immunodeficiency virus (HIV) drug metabolism. Transcriptional activation by rifampicin involves the CYP3A4 gene 5'-upstream region. Consequently, variation may interfere with transcription and enzymatic activity and even drug response. However, genetic polymorphisms and distribution of CYP3A4 allelic frequencies in individuals from Rio de Janeiro remain unknown. The aim of this study was to conduct research into sequencing the CYP3A4 5'-upstream region in Brazilian patients with and without HIV. This follow-up study involved 106 individuals undergoing treatment for TB and/or HIV. The CYP3A4 5'-upstream region was analyzed using PCR, sequencing and clinical data. Male patients revealed a higher HIV frequency (p=0.021). The TB forms observed were pulmonary (48.1%), extrapulmonary (22.64%) and disseminated (27.36%). Lymph node form was the most frequent (70.83%) extrapulmonary form of TB. The only single nucleotide polymorphism detected in the population was c.-392A>G. Genotypes observed were CYP3A4*1A/CYP3A4*1A (45.3%), CYP3A4*1A/CYP3A4*1B (40.6%) and CYP3A4*1B/CYP3A4*1B (14.2%), revealing a different distribution with extrapulmonary TB cases (17.6% CYP3A4*1A/CYP3A4*1B and 23.5% CYP3A4*1B/CYP3A4*1B). The CYP3A4*1A allele was found to be associated with tobacco use. The CYP3A4*1B mutant allele occurred in 34% of patients. This study revealed that the CYP3A4 5'-upstream regulatory region was highly conserved with the exception of the -392 position. Genotype association with tobacco suggests that CYP3A4 may participate in tobacco metabolism. Genotype distribution inversion in extrapulmonary TB cases suggests that CYP3A4 may be involved in TB prognosis.

Esophageal cancer (EC) is among the 10 most common and fatal malignacies in the world, presenting a marked geographic variation in incidence rates between and within different countries. The TP53 tumor suppressor gene is highly mutated in esophageal tumors and its mutation pattern can offer clues to the etiopathology of the tumor. As Brazil presents one of the highest incidence areas in the West, a deeper knowledge of the molecular mechanisms related to EC development in the Brazilian population is needed. We analyzed the mutation profile of 110 esophageal squamous cell carcinomas (ESCC) of patients from Southeastern Brazil (Rio de Janeiro and São Paulo) and collected data regarding alcohol intake and tobacco smoking. We detected 41 mutations in tumor samples from 38 patients. There was no association between mutation frequency and tobacco smoking or alcohol drinking. The most frequently mutated codons were 179, 214, 220 and 248. Codons 179, 220 and 248 are hot-spots for ESCC, but codon 214 presents only 0.7% of the mutations registered in the IARC database. The mutation profile revealed a high percentage of mutations at A:T base pairs (34.1%) followed by deletions (17.1%). We concluded that the mutation profile detected in this study is different from that of patients from Southern Brazil but very similar to that previously seen in French patients, being characterized by a high frequency of mutations at A:T base pairs, which may be associated with acetaldehyde, the metabolic product of ethanol., (Copyright © 2009 Elsevier B.V. All rights reserved.)

Holoprosencephaly (HPE), which results from failed or incomplete midline forebrain division early in gestation, is the most common forebrain malformation. The etiology of HPE is complex and multifactorial. To date, at least 12 HPE-associated genes have been identified, including TGIF (transforming growth factor beta-induced factor), located on chromosome 18p11.3. TGIF encodes a transcriptional repressor of retinoid responses involved in TGF-β signaling regulation, including Nodal signaling. TGIF mutations are reported in approximately 1-2% of patients with non-syndromic, non-chromosomal HPE. We combined data from our comprehensive studies of HPE with a literature search for all individuals with HPE and evidence of mutations affecting TGIF in order to establish the genotypic and phenotypic range. We describe 2 groups of patients: 34 with intragenic mutations and 21 with deletions of TGIF. These individuals, which were ascertained from our research group, in collaboration with other centers, and through a literature search, include 38 probands and 17 mutation-positive relatives. The majority of intragenic mutations occur in the TGIF homeodomain. Patients with mutations affecting TGIFrecapitulate the entire phenotypic spectrum observed in non-chromosomal, non-syndromic HPE. We identified a statistically significant difference between the 2 groups with respect to inheritance, as TGIF deletions were more likely to be de novo in comparison to TGIF mutations (χ(2) ((2)) = 6.97, p(permutated) = 0.0356). In addition, patients with TGIF deletions were also found to more commonly present with manifestations beyond the craniofacial and neuroanatomical features associated with HPE (p = 0.0030). These findings highlight differences in patients with intragenic mutations versus deletions affecting TGIF, and draw attention to the homeodomain region, which appears to be particularly relevant to HPE. These results may be useful for genetic counseling of affected patients.

Mutations within either the SHH gene or its related pathway components are the most common, and best understood, pathogenetic changes observed in holoprosencephaly patients; this fact is consistent with the essential functions of this gene during forebrain development and patterning. Here we summarize the nature and types of deleterious sequence alterations among over one hundred distinct mutations in the SHH gene (64 novel mutations) and compare these to over a dozen mutations in disease-related Hedgehog family members IHH and DHH. This combined structural analysis suggests that dysfunction of Hedgehog signaling in human forebrain development can occur through truncations or major structural changes to the signaling domain, SHH-N, as well as due to defects in the processing of the mature ligand from its pre-pro-precursor or defective post-translation bi-lipid modifications with palmitate and cholesterol.

Holoprosencephaly (HPE) is the most common developmental anomaly of the human forebrain; however, the genetics of this heterogeneous and etiologically complex malformation is incompletely understood. Heterozygous mutations in SIX3, a transcription factor gene expressed in the anterior forebrain and eyes during early vertebrate development, have been frequently detected in human HPE cases. However, only a few mutations have been investigated with limited functional studies that would confirm a role in HPE pathogenesis. Here, we report the development of a set of robust and sensitive assays of human SIX3 function in zebrafish and apply these to the analysis of a total of 46 distinct mutations (19 previously published and 27 novel) located throughout the entire SIX3 gene. We can now confirm that 89% of these putative deleterious mutations are significant loss-of-function alleles. Since disease-associated single point mutations in the Groucho-binding eh1-like motif decreases the function in all assays, we can also confirm that this interaction is essential for human SIX3 co-repressor activity; we infer, in turn, that this function is important in HPE causation. We also unexpectedly detected truncated versions with partial function, yet missing a SIX3-encoded homeodomain. Our data indicate that SIX3 is a frequent target in the pathogenesis of HPE and demonstrate how this can inform the genetic counseling of families.

The ZIC genes comprise a family of transcriptional factors associated with neural tube defects (NTDs) in mice and with holoprosencephaly in humans. An allelic variant of ZIC2, a CAC repeat within the first exon, was reported in association with an increased risk of non-syndromic NTDs in patients with a Hispanic ethnic background. We investigated whether this 10-residue histidine tract polymorphism of the ZIC2 gene (c.718&#95;720dupCAC) was associated with the risk of NTDs in a sample of 138 patients and their parents from the Latin American Collaborative Study of Congenital Malformations (ECLAMC) hospital network. Analysis with log-linear models of 138 family triads of mother, father and affected child did not provide evidence to support the notion that case (or maternal) 10H/10H or -/10H genotypes were associated with NTDs in this South American population sample, where the 10H variant occurred in 5% of newborns affected with NTDs. We also described the first example of the homozygous state of the 10H allele in a patient with cephalocele, holoprosencephaly and microphthalmia, but did not ascertain whether this polymorphism is associated with the increased risk of a specific subgroup of NTDs, as a normal father of a patient with anencephaly presented the same genotype.

Background: Single median maxillary central incisor (SMMCI) is a rare anomaly that may occur alone or associated with other conditions, frequently as part of the holoprosencephaly (HPE) spectrum. However, it has been suggested that SMMCI alone, or associated with some midline defects, may be considered a different entity from HPE (OMIM: 147250). Families with SMMCI, without HPE cases, are difficult to counsel for the risk of HPE in future generations because the same midline defects described as part of the "SMMCI syndrome" can also be part of the HPE spectrum., Methods: We screened five cases of SMMCI for mutations in three HPE genes, SHH, TGIF, and SIX3., Results: A missense mutation c.686C>T was found in the gene SIX3 of one patient, which did not differ from the accepted 20% of known HPE gene mutations among all HPE cases. Our results and an extensive literature review of gene mutations in patients with SMMCI showed that 27/28 of them were in HPE genes: SHH (n = 21), SIX3 (n = 3), TGIF (n = 1), GLI2 (n = 1), and PTCH (n = 1), and only one in the SALL4 gene., Conclusions: The clinical findings in patients with SMMCI without HPE in families with mutations in HPE genes cannot be distinguished from the findings reported in the SMMCI syndrome. Therefore, persons with SMMCI and their relatives should be carefully investigated for related midline disorders, especially of the HPE spectrum, and all known HPE genes screened., (2007 Wiley-Liss, Inc.)

Holoprosencephaly (HPE) is the most common structural malformation of the forebrain and face in humans. Our current understanding of the pathogenesis of HPE attempts to integrate genetic susceptibility, evidenced by mutations in the known HPE genes, with the epigenetic influence of environmental factors. Mutations or deletions of the human TGIF gene have been associated with HPE in multiple population cohorts. Here we examine the functional effects of all previously reported mutations, and describe four additional variants. Of the eleven sequence variations in TGIF, all but four can be demonstrated to be functionally abnormal. In contrast, no potentially pathogenic sequence alterations were detected in the related gene TGIF2. These results provide further evidence of a role for TGIF in HPE and demonstrate the importance of functional analysis of putative disease-associated alleles.

Here, we report six Brazilian patients with holoprosencephaly caused by SIX3 mutations. Missense mutations were more common than frameshift mutations. Comparison of patients with missense versus frameshift mutations was essentially unremarkable. Our cases suggest that SIX3 mutations result in a more severe phenotype than other gene mutations for holoprosencephaly. One patient had a double SIX3 mutation, which has not been reported previously. In our SIX3 mutations, three were transmitted by the paternal side, two were transmitted by the maternal side, and one was a de novo event. Mutations in normal parents with severe involvement of their offspring does not allow prediction of phenotypic severity, which makes genetic counseling difficult.