Aline dos Santos Moreira

Genome Sequence of Mycobacterium bovis BCG Moreau, the Brazilian Vaccine Strain against Tuberculosis

Mycobacterium bovis bacillus Calmette-Guérin (BCG) is the only vaccine available against tuberculosis, and the strains used worldwide represent a family of daughter strains with distinct genotypic characteristics. Here we report the complete genome sequence of M. bovis BCG Moreau, the strain in continuous use in Brazil for vaccine production since the 1920s.

Prevalence of the BRCA1 founder mutation c.5266dupin Brazilian individuals at-risk for the hereditary breast and ovarian cancer syndrome

About 5-10% of breast and ovarian carcinomas are hereditary and most of these result from germline mutations in the BRCA1 and BRCA2 genes. In women of Ashkenazi Jewish ascendance, up to 30% of breast and ovarian carcinomas may be attributable to mutations in these genes, where 3 founder mutations, c.68_69del (185delAG) and c.5266dup (5382insC) in BRCA1 and c.5946del (6174delT) in BRCA2, are commonly encountered. It has been suggested by some authors that screening for founder mutations should be undertaken in all Brazilian women with breast cancer. Thus, the goal of this study was to determine the prevalence of three founder mutations, commonly identified in Ashkenazi individuals in a sample of non-Ashkenazi cancer-affected Brazilian women with clearly defined risk factors for hereditary breast and ovarian cancer (HBOC) syndrome. Among 137 unrelated Brazilian women from HBOC families, the BRCA1 c.5266dup mutation was identified in seven individuals (5%). This prevalence is similar to that encountered in non-Ashkenazi HBOC families in other populations. However, among patients with bilateral breast cancer, the frequency of c.5266dup was significantly higher when compared to patients with unilateral breast tumors (12.1% vs 1.2%, p = 0.023). The BRCA1 c.68_69del and BRCA2 c.5946del mutations did not occur in this sample. We conclude that screening non-Ashkenazi breast cancer-affected women from the ethnically heterogeneous Brazilian populations for the BRCA1 c.68_69del and BRCA2 c.5946del is not justified, and that screening for BRCA1 c.5266dup should be considered in high risk patients, given its prevalence as a single mutation. In high-risk patients, a negative screening result should always be followed by comprehensive BRCA gene testing. The finding of a significantly higher frequency of BRCA1 c.5266dup in women with bilateral breast cancer, as well as existence of other as yet unidentified founder mutations in this population, should be further assessed in a larger well characterized high-risk cohort.

CDKN2A (p14ARF/p16INK4a) and ATM promoter methylation in patients with impalpable breast lesions

Early detection of breast cancer increases the chances of cure, but the reliable identification of impalpable lesions is still a challenge. In spite of the advances in breast cancer detection, the molecular basis of impalpable lesions and the corresponding circulating biomarkers are not well understood. Impalpable lesions, classified by radiologists according to the Breast Imaging Reporting and Data System in the categories 3 and 4, can be either benign or malignant (slow growing or aggressive). In this article, we report the DNA methylation pattern in CDKN2A (p14(ARF)/p16(INK4a)) and in ATM gene promoters from 62 impalpable lesions, 39 peripheral blood samples, and 39 saliva samples, assessed by methylation-specific polymerase chain reaction method. ATM showed the greatest percentage of methylation in DNA from lesions (benign and malignant), blood (even with p16(INK4a)), and saliva, followed by p16(INK4a) and p14(ARF). Among the malignant cases, ATM promoter was the most hypermethylated in lesion DNA and in blood and saliva DNAs, and p14(ARF), the least. The highest percentage of p16(INK4a) methylation was found in the blood. Finally, our data are relevant because they were obtained using impalpable breast lesions from patients who were carefully recruited in 2 public hospitals of Rio de Janeiro.

Human glutathione S-transferase polymorphisms associated with prostate cancer in the Brazilian population

OBJECTIVE To evaluate the influence of polymorphisms in GSTA1, GSTM1, GSTT1, and GSTP1 in the risk of developing Prostate Cancer (PCa) in a population of Rio de Janeiro and compare the distribution of allele and genotype frequencies of the polymorphisms analyzed in the present study population with other regions in the country and different ethnic groups. MATERIALS AND METHODS We analyzed a sample of the Brazilian population, comprising 196 patients with PCa treated by the urology services of the Brazilian National Cancer Institute (INCA) and Mario Kroeff Hospital (HMK), and 208 male blood donors from the Clementino Fraga Filho Hospital, Federal University of Rio de Janeiro (UFRJ). The polymorphisms were determined in DNA, extracted from peripheral blood leucocytes using the Polymerase Chain Reaction and Restriction Fragment Length Polymorphism (PCR-RFLP). RESULTS Our results showed that the distribution of polymorphisms can vary significantly according to the Brazilian region and ethnic groups. The distribution of allele and genotype frequencies of the polymorphism GSTA1 was statistically different between cases and controls. Genotypes (A / B + B / B) were associated with protection (OR = 0.61, 95% CI = 0.40-0.92) for PCa in comparison to genotype A / A. CONCLUSION The distribution of genotype frequencies of the polymorphism GSTA1 was statistically different between the case and control groups (p = 0.023), and the presence of genotypes A / B and B / B suggests a protective role against the risk of PCa compared to genotype A / A. This is the first study that reports the genotypic frequency of this polymorphism and its association with PCa in a Brazilian population sample.

Impact of reduced levels of APE1 transcripts on the survival of patients with urothelial carcinoma of the bladder

Molecular evidence indicates that alterations in genes involved in the maintenance of genome stability may be related to susceptibility to bladder carcinoma. Our goal was to evaluate the prognostic role of base excision repair (BER) genes in a cohort of patients diagnosed with primary urothelial carcinoma of the bladder (UCB). The levels of all APE1, XRCC1 and POLB transcripts were detected by quantitative real-time PCR (qPCR) technique in tumor samples from 52 patients undergoing transurethral resection (TUR) for primary UCB at the Department of Urology, Brazilian National Cancer Institute, Rio de Janeiro. Increased levels of APE1, XRCC1 and POLB transcripts were significantly associated with high-grade tumors when compared to these levels in low-grade tumors (p<0.01) and could be attributed to different mechanisms of transcriptional regulation as a response to tumorigenesis and oxidative stress. By analyzing the collected data in the present study, regardless of pathological grade or stage, univariate analysis revealed that the reduced levels of APE1 transcripts were significantly associated with cancer-specific mortality (p=0.032). Furthermore, the variant genotype (TG/GG) of the APE1 T1349G polymorphism was observed in 75% of a subset of patients who concomitantly experienced reduced levels of the APE1 transcript and death and/or recurrence events. Taken together, our data reinforce the idea that human DNA repair mechanisms must be finely regulated in order to avoid instability leading to tumorigenesis and poor clinical outcomes in UCB patients.

Complete genome sequence of a hepatitis B virus isolate of genotype D2, subtype adrq + , from Brazil

Hepatitis B virus (HBV) has been classified into 10 distinct serological subtypes of the surface antigen (HBsAg) that can be predicted by sequencing of the corresponding S gene. HBV genotype D usually displays determinants of subtypes ayw2 or ayw3. On the other hand, subtype adrq+ has been found exclusively in association with genotype C. Here, we describe the first HBV genome (isolate BR32) belonging to genotype D with the serological subtype adrq+. This isolate had a genome length of 3,062 nucleotides (nt), and no recombination events were observed in the BR32 genome that could explain the occurrence of the subtype adr in a genotype D isolate. Analysis of the quasispecies population revealed that 28 out of 30 clones (93%) were of subtype adrq+, while the subtypes of the two remaining could not be determined, since they contained an S residue (instead of K or R) at position 122 of HBsAg. These results will contribute to further epidemiological and evolutionary studies of HBV.

Effect of selection for eventing on the MSTN gene in Brazilian sport horses.

ABSTRACT 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.

TGF-β Polymorphisms Are a Risk Factor for Chagas Disease

Transforming growth factor β1 (TGF-β1) is an important mediator in Chagas disease. Furthermore, patients with higher TGF-β1 serum levels show a worse clinical outcome. Gene polymorphism may account for differences in cytokine production during infectious diseases. We tested whether TGFB1 polymorphisms could be associated with Chagas disease susceptibility and severity in a Brazilian population. We investigated five single-nucleotide polymorphisms (−800 G>A, −509 C>T, +10 T>C, +25 G>C, and +263 C>T). 152 patients with Chagas disease (53 with the indeterminate form and 99 with the cardiac form) and 48 noninfected subjects were included. Genotypes CT and TT at position −509 of the TGFB1 gene were more frequent in Chagas disease patients than in noninfected subjects. Genotypes TC and CC at codon +10 of the TGFB1 gene were also more frequent in Chagas disease patients than in noninfected subjects. We found no significant differences in the distribution of the studied TGFB1 polymorphisms between patients with the indeterminate or cardiac form of Chagas disease. Therefore, −509 C>T and +10 T>C TGFB1 polymorphisms are associated with Chagas disease susceptibility in a Brazilian population.

Health survey and assessment of the polymorphisms BRCA1/P871L, BRCA1/Q356R, and BRCA2/N372H in female gas station workers in Rio de Janeiro

Gas station workers are exposed to chemicals known to be carcinogenic, especially benzene. The objective was to analyze the health problems of female gas station workers by means of sociodemographic and clinical questionnaires, and laboratorial exams. We performed the genotyping of the polymorphisms BRCA1/P871L and BRCA1/Q356R by Polymerase Chain Reaction‐Restriction Fragment Length Polymorphism, and of variant allele BRCA2/N372H through direct sequencing. The female workers showed a higher concentration of monocytes (P = 0.039); a greater number of spontaneous abortions (P = 0.025, OR = 4.977, 95% CI = 1.135–30.669); higher tobacco consumption (P = 0.013); and higher alcohol consumption (P = 0.05). The statistical analysis of the polymorphisms associated with the variables monocyte concentration and miscarriage number did not reveal a significant relationship, and smoking and spontaneous abortion were not statistically associated either. Environ. Mol. Mutagen. 58:730–734, 2017.

Screening of mutations in the additional sex combs like 1, transcriptional regulator, tumor protein p53, and KRAS proto-oncogene, GTPase/NRAS proto-oncogene, GTPase genes of patients with myelodysplastic syndrome

Myelodysplastic syndrome (MDS) is a heterogeneous group of clonal bone marrow disorders characterized by ineffective hematopoiesis, different degrees of cellular dysplasia, and increased risk of progression to acute myeloid leukemia. International Prognostic Scoring System is the gold standard for MDS classification; however, patients exhibiting different clinical behaviors often coexist in the same group, indicating that the currently available scoring systems are insufficient. The genes that have recently been identified as mutated in MDS, including additional sex combs like 1, transcriptional regulator (ASXL1), tumor protein p53 (TP53), and KRAS proto-oncogene and GTPase (KRAS)/NRAS proto-oncogene, GTPase (NRAS), may contribute to a more comprehensive classification, as well as to the prognosis and progression of the disease. In the present study, the mutations in the ASXL1, TP53 and NRAS/KRAS genes in 50 patients were evaluated by sequencing genomic bone marrow DNA. Nine patients (18%) presented with at least one type of mutation. Mutations in TP53 were the most frequent in six patients (12%), followed by ASXL1 in two patients (4%) and NRAS in one patient (2%). The nine mutations were detected in patients with low- and high-risk MDS. The screening of mutations in MDS cases contributes to the application of personalized medicine.