Evaluation of HPV and EBV in OSCC and the expression of p53, p16, E-cadherin, COX-2, MYC, and MLH1.

OBJECTIVE: This study aimed to evaluate the presence of human papillomavirus (HPV) and Epstein-Barr virus (EBV) and the expression of p53, p16, E-cadherin, COX-2, MLH1, and MYC in oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: One hundred OSCC specimens were submitted to in situ hybridization for HPV and EBV, and immunohistochemistry for detection of the human proteins. RESULTS: Thirty-one cases showed HPV in tumor tissue. EBV was not detected in any case investigated. The HPV(+) group demonstrated an increase of staining scores for nuclear p16 (p = .047), cytoplasmic MYC (p = .002), while a decrease for nuclear MLH1 (p = .048), suggesting that HPV may upregulate the expression of the first two proteins and down-regulate the latter. CONCLUSION: Our findings reinforce the hypothesis of the HPV-related oral carcinogenesis involving the expression of p16 and MYC, and MLH1 suppression. Exclusively cytoplasmic stainings for p16, MLH1, and MYC were also associated with more advanced tumors. Finally, in view of the lack of studies correlating the HPV or EBV infection to the expression of oncoproteins, more researches assessing a broader panel of markers and employing different approaches are still necessary in order to understand the role of these viruses as well as the molecular mechanisms involved in the development and progression of oral carcinomas.

Contribution of genetic polymorphisms of interleukins IL1B-511 C/T, IL1RN VNTR, IL6-174 G/C, and IL8-251 A/T in gastric lesions: gender and Helicobacter pylori genes matter.

Stomach pathologies develop in a complex interaction between the host's genetic background and H. pylori virulent genes. Thus, our study aimed to compare active chronic gastritis (ACG), and intestinal metaplasia (IM) with inactive chronic gastritis (ICG), according to interleukin polymorphisms of IL6-174 G/C, IL8-251 A/T, IL1ß-511 C/T, and IL1RN VNTR taking into account patient gender and H. pylori genotypes. Interleukin polymorphisms were determined by RFLP-PCR and H. pylori genotype by PCR. IL6-174 GC and IL8-251 T allele showed a protective effect in women against ACG development and, conversely, IL8-251 polymorphism showed a risk for men. More virulent H. pylori strains were associated with the IL8-251 T allele and IL1ß-511 T allele in the AGC, and the vacA m1 allele and cagE gene from H. pylori was associated with the IM. Analysis of the progression of gastric lesions must take into account host variability genetic associated with genes H. pylori due to the relation between the virulent H. pylori genes and more severe gastric lesions, besides the relevance to the gender to IL6-174 and IL8-251 polymorphisms.

New insights on intercontinental origins of paternal lineages in Northeast Brazil.

BACKGROUND: The current Brazilian population is the product of centuries of admixture between intercontinental founding groups. Although previous results have revealed a heterogeneous distribution of mitochondrial lineages in the Northeast region, the most targeted by foreign settlers during the sixteenth century, little is known about the paternal ancestry of this particular population. Considering historical records have documented a series of territorial invasions in the Northeast by various European populations, we aimed to characterize the male lineages found in Brazilian individuals in order to discover to what extent these migrations have influenced the present-day gene pool. Our approach consisted of employing four hierarchical multiplex assays for the investigation of 45 unique event polymorphisms in the non-recombining portion of the Y-chromosome of 280 unrelated men from several Northeast Brazilian states. RESULTS: Primary multiplex results allowed the identification of six major haplogroups, four of which were screened for downstream SNPs and enabled the observation of 19 additional lineages. Results reveal a majority of Western European haplogroups, among which R1b-S116* was the most common (63.9%), corroborating historical records of colonizations by Iberian populations. Nonetheless, FST genetic distances show similarities between Northeast Brazil and several other European populations, indicating multiple origins of settlers. Regarding Native American ancestry, our findings confirm a strong sexual bias against such haplogroups, which represented only 2.5% of individuals, highly contrasting previous results for maternal lineages. Furthermore, we document the presence of several Middle Eastern and African haplogroups, supporting a complex historical formation of this population and highlighting its uniqueness among other Brazilian regions. CONCLUSIONS: We performed a comprehensive analysis of the major Y-chromosome lineages that form the most dynamic migratory region from the Brazilian colonial period. This evidence suggests that the ongoing entry of European, Middle Eastern, and African males in the Brazilian Northeast, since at least 500 years, was significantly responsible for the present-day genetic architecture of this population.

mtDNA structure: the women who formed the Brazilian Northeast.

BACKGROUND: The distribution of mitochondrial DNA (mtDNA) lineages in Brazil is heterogeneous due to different regional colonization dynamics. Northeastern Brazil, although being an important region in terms of human imigration and ethnic admixture, has little information regarding its population mtDNA composition. Here, we determine which mitochondrial lineages contributed to the formation of the Northeastern Brazilian population. Our sample consisted of 767 individuals distributed as follows i) 550 individuals from eight Northeastern states (Piauí, Ceará, Rio Grande do Norte, Paraíba, Pernambuco, Alagoas, Sergipe, and Bahia) which were sequenced for mtDNA hypervariable segments I, II, and III; ii) 217 individuals from Alagoas and Pernambuco (previously published data). Data analysis was performed through sequence alignment and Haplogrep 2.0 haplogroup assignment tools. Furthermore, maternal ancestry distribution was contextualized and, when possible, related to historical events to better understand the biological interactions and population dynamics that occurred in this region since the beginning of colonization. RESULTS: Unexpectedly, Amerindian mitochondrial ancestry was the highest in the Northeastern region overall, followed by African, European and non-Amerindian Asian, unlike previous results for this region. Alagoas and Pernambuco states, however, showed a larger African mtDNA frequency. The Northeastern region showed an intraregional heterogeneous distribution regarding ancestral groups, in which states/mesoregions located to the north had a prevalent Amerindian ancestral frequency and those to the south had predominance of African ancestry. Moreover, results showed great diversity of European haplogroups and the presence of non-Amerindian Asian haplogroups. CONCLUSIONS: Our findings are in disagreement with previous investigations that suggest African mitochondrial ancestry is the most prevalent in the Brazilian Northeast. The predominance of Amerindian lineages exemplifies the importance of indigenous women in the formation of the population, despite intense African slave entry and conflicts with European settlers. The variable distribution of ancestral groups observed in the Northeast is in accordance with historical records showing the similarities with colonization dynamics occurred in the Amazon region and the Brazilian Southeast. Moreover, the variety of European haplogroups suggests multiple origins of founding groups, specially those found in Western European populations.

The intricate interplay between MSI and polymorphisms of DNA repair enzymes in gastric cancer H.pylori associated.

Gastric cancer is the fourth most common type of cancer worldwide. Helicobacter pylori is a well-established risk factor and may cause injuries to genomic integrity through an inefficient DNA repair. This study aimed to examine the influence of polymorphisms in DNA repair enzymes using markers for microsatellite instability (MSI). Polymorphisms of DNA repair enzymes were detected by PCR-RFLP and MSI, by high resolution melt (HRM) analysis. Helicobacter pylori detection and genotyping were accomplished by PCR. MSI was observed in 47.5% of the cases and it was associated with the ERCC1 polymorphic allele, whereas MSI-H was associated with the XRCC3 heterozygous genotype. MSI was more frequent in intestinal gastric cancer (IGC), where it was associated with ERCC1 or RAD51 polymorphic alleles. Also, MSI-H was associated with the XRCC3 heterozygous. In diffuse gastric cancer (DGC), almost all of MGMT polymorphic genotype carriers showed MSI. Helicobacter pylori was positive in 94% of the cases and the most virulent strains were associated with MSI, mainly MSI-H. When the subtypes were considered, these associations were found only in the IGC and associated with more virulent strains. Among the cases with microsatellite instability, IGC showed a correlation between the XPD wild-type and the ERCC1 polymorphic allele, and all of them were infected by the most virulent strains. On the other hand, in DGC, the XPD polymorphic allele was correlated with the XRCC3 wild-type with no prevalence of H.pylori virulence. Our data demonstrated that polymorphisms in repair enzymes can interfere with the efficiency of the repair process, but it differs depending on the histological subtype and H.pylori involvement. Besides nucleotide excision repair, base excision repair and mismatch repair pathway, the homologous recombination are also involved.

A link between osteomyelitis and IL1RN and IL1B polymorphisms-a study in patients from Northeast Brazil.

Background and purpose - Treatment failure of osteomyelitis can result from genetic susceptibility, highlighting polymorphisms of the interleukin-1 (IL-1) family members, central mediators of innate immunity and inflammation. Polymorphisms are DNA sequence variations that are common in the population (1% or more) and represent multiple forms of a single gene. We investigated the association of IL1RNVNTR (rs2234663) and IL1B-511C > T (rs16944) polymorphisms with osteomyelitis development in patients operated on because of bone trauma. Patients and methods - 153 patients who fulfilled the inclusion criteria were enrolled from a referral public hospital for trauma. All the patients were followed up daily until hospital discharge and, after this, on an outpatient basis. Patients were treated with prophylactic antimicrobials and surgery according to traumatology service protocol. The IL1RNVNTR and the IL1B-511C > T polymorphisms were determined by PCR and PCR-RFLP, respectively. Results - The IL1RN*2/*2 genotype was associated (OR: 7; p < 0.001) with a higher risk of osteomyelitis and was also significantly associated with Staphylococcus aureus infection. The haplotypes (combination of different markers) *2-C and *2-T were also associated with osteomyelitis development. Interpretation - IL1B-511C > T and IL1RNVNTR polymorphisms were associated with osteomyelitis development, which may have implications for patients with bone traumas. These data may be relevant for new therapeutic strategies for this disease.

Association of genetic polymorphisms of IL1ß -511 C>T, IL1RN VNTR 86 bp, IL6 -174 G>C, IL10 -819 C>T and TNFα -308 G>A, involved in symptomatic patients with dengue in Brazil.

OBJECTIVE: In this study, single nucleotide polymorphisms (SNP) of interleukin (IL) 1ß -511C>T, IL1RN VNTR 86 bp, IL6 -174G>C, IL10 -819C>T and TNFα -308G>A were analyzed by PCR-RFLP with symptoms of dengue with the clinical features. SUBJECTS: 196 individuals admitted to the São José Infectious Diseases Hospital with suspected dengue infection. Dengue was confirmed in 111 of the patients. The control group consisted of 85 other individuals confirmed without dengue. RESULTS: It was demonstrated that the presence the T allele of IL1ß (P < 0.05) was associated with susceptibility to developing the disease. Other results also suggested that the polymorphism in the combinations IL6 × IL1ß (C and T alleles, respectively), IL1ß (T allele) × IL1RN (*2/*2 genotype), IL6 (C allele) × TNFα (A allele), IL10 (C/T genotype) × TNFα (A/A genotype) (P < 0.01, P = 0.01, P < 0.05 and P = 0.03, respectively) were associated with predisposition to developing the disease and its symptoms. CONCLUSIONS: In summary, the findings of this study in a Brazilian population point out the importance of studies of combinations of polymorphisms in the development of dengue, which can increase the risk of dengue infection and its severity.

CD38+CD8+ and CD38+CD4+ T Cells and IFN Gamma (+874) Polymorphism Are Associated with a Poor Virological Outcome.

The main objective of the work was to evaluate the use of CD38 on T lymphocytes, IFNγ (+874 A/T), and IL-10 (-1082 A/G) polymorphisms in HIV-infected patients under antiretroviral (ARV) therapy. Sixty-one patients were selected at the outpatient clinic for HIV infection at the Hospital São José de Doenças Infecciosas, Fortaleza, Ceará, Brazil. The patients were classified into two groups, according to viral load after one year of ARV therapy. In the aviremic group (group I), a reduction of 35.5% of CD38+CD4+ T cells was observed (p = 0.02) and 49.3% of CD38+CD8+ T cells (p = 0.001). In the viremic group (group II), a reduction of 37.2% of CD38+CD4+ T cells (p = 0.067), and 21.4% of CD38+CD8+ T cells (p = 0.60) occurred. No association was found between IL-10 (-1082) polymorphism and the type of response to ARV therapy. Regarding the gene polymorphism on IFNγ (+874 T/A), 73.34% of group I and 33.3% of group II presented the AA genotype. The relative risk of the individuals carrying AA genotype or the A allele and not being able to suppress the viral load level after one year of ARV therapy was 3.44 (1.25-9.45; p = 0.014) or 2.35 (1.05-5.26; p = 0.027), respectively. Our data suggested that an augmented frequency of activated CD38+CD8+ T cells as well as the presence of the A allele of IFNγ polymorphism could contribute to a reduced virological suppression in patients under antiretroviral therapy.

Characterization of Gastric Cardia Tumors: Differences in Helicobacter pylori Strains and Genetic Polymorphisms.

BACKGROUND: Gastric cancer results from a multifactorial process and is one of the most common causes of death worldwide. These tumors can arise in the distal stomach (non-cardia) and in the cardia region, presenting different characteristics and frequency of occurrence worldwide. AIMS: To search for differences between tumors of different locations that could explain the presence of cardia tumors, considering Helicobacter pylori strains and genetic polymorphisms. MATERIALS AND METHODS: DNA was extracted from gastric adenocarcinoma tissue of 127 patients. Helicobacter pylori genes were detected by PCR, and polymorphisms by PCR-RFLP. RESULTS: Most of the tumors were located in non-cardia. The genotype 28152GA of XRCC1 showed an increase in risk of cardia tumors. In analysis performed considering gender, women carrying TNF-308GA genotype showed a decreased risk of non-cardia tumors, while in men the decreased risk of non-cardia tumors was associated with TNF-308GG genotype. Genotypes combinations showed that the SNPs RAD51 135G>C, XRCC3 18067C>T, and XRCC1 28152G>A had some combinations more frequent in cardia tumors, with an increased risk. Patients infected by cagE-positive strains presented a positive correlation with non-cardia tumors. CONCLUSION: The results showed some susceptibility differences between tumors of different locations. There was an increased risk relationship between three repair enzyme SNPs and cardia tumors, and the G allele of the cytokine gene TNF negatively influenced the development of non-cardia tumors. Helicobacter pylori strains seemed to be different in the cardia region, where they were less virulent than those located in the distal region of the stomach.

Association of TP53 codon 72 and intron 3 16-bp Ins/Del polymorphisms with cervical cancer risk.

Cervical cancer incidence has grown worldwide, with it being a more significant problem in developing countries. Invasive squamous cell cervical cancers are preceded by a long phase of preinvasive disease, known as cervical intraepithelial neoplasia. Cervical cancer can develop when the virus takes advantage of any TP53 gene dysfunction of the host organism. TP53 is responsible for encoding the tumor suppressor p53 phosphoprotein, which helps preserve genome integrity. Currently, many studies have focused on genetic polymorphisms as an important contribution to cancer susceptibility, but few related to cervical intraepithelial neoplasia (CIN). Thus, the present study aimed to see whether patients with suspected CIN had TP53 gene polymorphisms that might have contributed to the development of neoplasia. This study included 133 women who were referred to the Cervical Pathology Clinic of the Maternity School Assis Chateaubriand MEAC for suspected cervical lesions. Polymorphism genotyping was carried out by the PCR-RFLP technique using DNA extracted from patients' blood. The most frequent genotype in both CIN(+) and CIN(-) patients was Arg/Pro TP53 codon 72 and A1A1 for 16-bp Del in intron 3. No risk of cervical cancer was found for the polymorphisms studied. However, a significant association was found when the two polymorphisms were combined: patients with the A1A1/ArgPro genotype were statistically more frequent in the CIN(-) group (p = 0.042), while A2A2-A1A2/ProArg was significantly more frequent in the CIN(+) group. The results of our study suggest that combined analysis of TP53 polymorphisms Arg72Pro and 16-bp Ins/Del may help to monitor the development of CIN in Brazilian women.

BubR1 and cyclin B1 immunoexpression in pleomorphic adenoma and polymorphous adenocarcinoma of minor salivary glands.

The immunoexpression of BubR1 and cyclin B1 in pleomorphic adenoma (PA) and polymorphic adenocarcinoma (PAC) in minor salivary glands is poorly studied. Thus, a retrospective and observational study was performed to provide a better understanding of the role and immunopositivity patterns of these proteins in these lesions. Sixteen cases of PA and 16 cases of PAC were selected. Parenchyma cells were submitted to quantitative immunohistochemical analysis through the labeling index. Cytoplasmic immunoexpression of BubR1 was observed in neoplastic cells from all analyzed PA and PAC cases. All PA cases and 93.7% of PAC exhibited nuclear immunoexpression of BubR1. Higher cytoplasmic and nuclear immunoexpression of BubR1 was observed in PAC (p = 0.001 and p = 0.122, respectively). Cytoplasmic immunoexpression of cyclin B1 was observed in all cases of PA and PAC, with a higher labeling index in the latter (p < 0.001). There was a significant positive correlation between nuclear and cytoplasmic BubR1 immunoexpressions (p < 0.001) in PA and a significant negative correlation between BubR1 and cyclin B1 cytoplasmic immunoexpressions (p = 0.014) in PAC. The higher cytoplasmic and nuclear immunoexpression of BubR1 in PACs suggests the continuous maintenance of neoplastic cells in the cell cycle and migration. Higher immunoexpression of cyclin B1 supports this lesion's enhanced proliferative and migration ability.

Prognostic impact of miR-125b and miR-155b and their relationship with MYC and TP53 in diffuse large B-cell lymphoma: cell-of-origin classification matters.

Tumoral microRNAs, such as miR-125b and miR-155b, are important gene expression regulators with complex pathogenetic mechanisms. However, their role in DLBCL, especially when cell-of-origin classification is considered, are still to be elucidated. In a series of 139 DLBCL cases considering germinal center (GC) versus nonGC subtypes, we investigated miR-125b and miR-155b expression by in situ hibridization and their association with some immunophenotypic presentations, including MYC, BCL2 and TP53 expression, MYC, BCL2 and BCL6 translocation status, as well as clinicopathological features and outcomes. miR-125b detection was positively correlated to the Ki-67 index (P = 0.035) in the nGC. Considering the GC subgroup, the percentage of miR-125b positive cells was also correlated to either MYC and MYC/BCL2 double expression (P = 0.047 and P = 0.049, respectively). When it comes to nGC patients, miR-155b percentage and intensity, as well as Allred score, were positively correlated to disease progression (P = 0.038, P = 0.057 and P = 0.039, respectively). In a multivariate analysis, GC phenotype was a significant independent factor associated with higher OS (P = 0.007) and, considering the nGC group, although not significant, the expression of TP53, miR-125b and miR-155b seems to be potential prognostic biomarkers in these tumors. This study demonstrated different pathways based on cell-of-origin classification and highlighted different clinical outcomes. miR-125b, miR-155b and TP53 expression may also represent potential prognostic factors in nGC-DLBCL.

Helicobacter pylori genotype and polymorphisms in DNA repair enzymes: where do they correlate in gastric cancer?

BACKGROUND AND OBJECTIVES: One of the mechanisms proposed by which H. pylori causes gastric cancer (GC) is through DNA damage due to chronic inflammation. Genomic integrity is guaranteed by repair enzymes such as APE-1, OGG-1, and PARP-1. Host genetic polymorphisms associated with the bacterial strain may influence the ability to repair the damage, contributing to the development of H. pylori-associated GC. The aim of this study was to determine the association of the polymorphisms APE-1 (T2197G), OGG-1 (C1245G), and PARP-1 (A40676G) with H. pylori-genotype in 109 patients with GC. METHODS: Polymorphism was assessed by polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) and H. pylori detection/genotyping by PCR. RESULTS: In the intestinal subtype, PARP-1 wild-type was more frequent (P=0.001) in patients >50 years old. The repair enzymes genotypes analyzed in combination showed that the less pathogenic strains are associated with the APE-1 polymorphic allele and, unexpectedly, with PARP-1 wild-type, but this last one associated with APE-1 polymorphic allele or in older patients. CONCLUSIONS: Our results indicate the importance of H. pylori and APE-1 genotypes in the gastric carcinogenesis. Also, support the hypothesis of a decrease of PARP-1 wild-type activity in older individuals. Taken together these data may be an important clue to understand the role of low-virulence strains of H. pylori in gastric carcinogenesis and point the importance to analyze the polymorphisms as a group.

TP53 codon 72 and intron 3 polymorphisms and mutational status in gastric cancer: an association with tumor onset and prognosis.

Although TP53 alterations have been studied in human tumors, data considering the role of two common TP53 polymorphisms (Pro72Arg in codon 72 and Ins16bp in intron 3) and their associations with TP53 mutations in gastric cancer are very limited. Thus, we analyzed these parameters taking into consideration the clinicopathological data. DNA from 106 gastric tumor samples was available for TP53 Pro72Arg and TP53 Ins16bp polymorphism genotyping by PCR-RFLP and PCR, respectively. The mutational status of the TP53 exons 5-7 was assessed by the single-strand conformational polymorphism test. The TP53 72ArgArg genotype was statistically associated with patients aged ≥65 years (p = 0.039), and the intron 3 A2A2 genotype was correlated with late-stage tumors (III and IV; p = 0.043). Considering both polymorphisms, a negative correlation between the TP53 Pro-A1 haplotype and age <65 years (r = -0.211; p = 0.030) was found. Taking into account the TP53 mutations, the Pro/Pro genotype was positively correlated with the presence of exon 7 mutations (p = 0.049), and a correlation between this genotype and the number of mutations in TP53 was observed (p = 0.019). This study corroborates the understanding of TP53 polymorphisms in gastric carcinogenesis, especially regarding the genetic features in tumor onset and prognosis.

hTERT, MYC and TP53 deregulation in gastric preneoplastic lesions.

BACKGROUND: Gastric cancer is a serious public health problem in Northern Brazil and in the world due to its high incidence and mortality. Despite the severity of the disease, more research is needed to better understand the molecular events involved in this intestinal-type gastric carcinogenesis process. Since precancerous lesions precede intestinal-type gastric cancer, here, we evaluated the hTERT, MYC, and TP53 mRNA and protein expression, as well as TP33 copy number, in gastric preneoplastic lesions. METHODS: We evaluated 19 superficial gastritis, 18 atrophic gastritis, and 18 intestinal metaplasia from cancer-free individuals of Northern Brazil. Quantitative reverse transcription PCR was used to analyze the mRNA expression and immunohistochemical methods were used to assess protein immunoreactivity in tissue samples. The number of TP53 gene copies was investigated in gastric diseases by quantitative PCR. RESULTS: We observed hTERT, MYC, and p53 immunoreactivity only in intestinal metaplasia samples. The immunoreactivity of these proteins was strongly associated with each other. A significantly higher MYC mRNA expression was observed in intestinal metaplasia compared to gastritis samples. Loss of TP53 was also only detected in intestinal metaplasia specimens. CONCLUSIONS: We demonstrated that hTERT, MYC, and TP53 are deregulated in intestinal metaplasia of individuals from Northern Brazil and these alterations may facilitate tumor initiation.

Associations of polymorphisms of folate cycle enzymes and risk of breast cancer in a Brazilian population are age dependent.

Polymorphisms in genes involved in folate metabolism have been shown to be implicated in breast cancer risk but with contradictory results. In this case-control study, we investigated the association between MTHFR C677T and A1298C, TYMS 5'-UTR, MTR A2756G and cSHMT C1420T and also the folate carrier (RFC1 G80A) and breast cancer risk in a northeastern Brazilian population. The study included 183 women diagnosed with breast cancer and 183 controls volunteers without any history of cancer. Also a significant number of healthy individuals were included for allelic frequency in the population studied. Risk of breast cancer was estimated by conditional logistic regression. An association with risk was found for women carrying the MTR A2756G polymorphic allele (AG, P = 0.0036; AG/GG, P = 0.0040), and a protective effect in carriers of the RFC1 G80A polymorphic allele (GA, P = 0.0015; AA, P = 0.0042). Stratifying the data by age (cutoff point of 50 years old), different distributions were observed for breast cancer risk. For women ≤50 years, the risk observed in the presence of the polymorphic allele MTR 2756 (AG/GG) in the general analysis was, restricted to this age group (P = 0.0118). Conversely, for women over 50, the risk of breast cancer development was statistically associated with the MTHFR 677CT genotype, but especially significant was risk associated with the presence of the polymorphic allele of cSHMT C1420T (P = 0.0120) and the protective effect associated with the RFC1 G80A polymorphism allele (P = 0.0021), was restrict to this age group. These data indicate that the cutoff age used (50 years old) was appropriate, since it was able to discriminate risk in each age group in the population studied and also to point to the importance of age in the analyses of cancer-associated polymorphisms.

Epstein-Barr virus-associated gastric carcinoma in Brazil: comparison between in situ hybridization and polymerase chain reaction detection.

Epstein-Barr virus (EBV) has been associated with 10% of gastric carcinomas. The aim of this study was to determine the frequency of EBV in gastric carcinomas in Brazil assessed by in situ hybridization (ISH) and PCR, which would contribute to the characterization of the clinical and pathological aspects of EBV-associated gastric carcinomas. One hundred and ninety-two gastric carcinoma cases were collected at hospitals in two Brazilian states. Seventy-three out of 151 cases were PCR(+), while 11/160 cases were ISH(+). Nine out of eleven ISH(+) cases displayed a diffuse staining pattern and 2 out of 11 a focal pattern. Both techniques showed that the EBV(+) cases were characterized by their association with males, older patients, lower gastric region, intestinal type, advanced stage and poorly to moderately differentiated tumors. The concordance between the two techniques was 55.8% (Cohen's kappa index = 0.034). Four cases were ISH(+)/PCR(-), while 49 cases were PCR(+)/ISH(-). Only two cases showed stained lymphocytes by ISH and one of them was PCR(-). The observed discrepancy between the two techniques could not be explained just by the elevated accuracy of PCR. ISH(+)/PCR(-) carcinomas may be encountered if EBV is not present in the whole tumor tissue or if there are polymorphisms in the sequences of the viral genome amplified. On the other hand, the high frequency of PCR(+) results associated with the absence of ISH staining in lymphocytes and/or tumors cells suggests that the virus may be present in tumor cells or other cell types without expressing EBER1, the target of the ISH technique.

High Frequency of Epstein-Barr Virus and Absence of Papillomavirus in Breast Cancer Patients from Brazilian Northeast.

OBJECTIVE: This study aimed to determine the presence of Epstein-Barr Virus (EBV) and Human papillomavirus (HPV) in breast cancer with patients from Northeast of Brazil, considering the molecular subtypes and also taking in account the relation with TP53 immunoexpression. METHODS: Seventy-five samples of invasive breast carcinoma with no special type were selected from pathology archives at Federal University of Ceará. EBV was detected by In situ hybridization (ISH) and immunohistochemistry (IHC) and HPV was detected by PCR. ISH was performed using EBER1 probe (Shibata et al., 1991; Bacchi et al., 1996) while IHC was performed on histological formalin-fixed paraffin-embedded tissue samples (Hsu et al., 1981). PCR methodology (Haws et al., 2004) was used to amplify the genetic material of human papillomavirus. The amplification products were electrophoretic analyzed on 1% agarose gel. The data analyses were carried out using the statistical software EPINFO® version 6.04d and SPSS version 17.0 (SPSS Inc., Chicago, IL). Statistically significant differences were evaluated by the chi-square test and Fisher's exact test and correlations between groups were analyzed by Spearman's and Pearson's rank correlation coefficient. RESULTS: 69.4% of the cases were EBNA1 positives by IHC. EBNA1 positive tumors had lower Ki-67 index (0-40%), while EBNA1 negative cases had relevant higher Ki-67 index (41-100%) (p = 0.06). EBV was present in all tumor grades, with a high frequency in grade I and III tumors comparing to EBNA1 negative cases. No HPV positive cases were observed. CONCLUSION: Regarding the results from this study, we support the hypothesis that EBV can be involved on breast tumorigenesis.

Inactivation of COX-2, HMLH1 and CDKN2A gene by promoter methylation in gastric cancer: relationship with histological subtype, tumor location and Helicobacter pylori genotype.

OBJECTIVE: We aimed to evaluate the inactivation of COX-2, HMLH1 and CDKN2A by promoter methylation and its relationship with the infection by different Helicobacter pylori strains in gastric cancer. METHODS: DNA extracted from 76 H. pylori-positive gastric tumor samples was available for promoter methylation identification by methylation-specific PCR and H. pylori subtyping by PCR. Immunohistochemistry was used to determine COX-2, p16(INK4A) and HMLH1 expression. RESULTS: A strong negative correlation was found between the expression of these markers and the presence of promoter methylation in their genes. Among cardia tumors, negativity of p16(INK4A) was a significant finding. On the other hand, in noncardia tumors, the histological subtypes had different gene expression patterns. In the intestinal subtype, a significant finding was HMLH1 inactivation by methylation, while in the diffuse subtype, CDKN2A inactivation by methylation was the significant finding. Tumors with methylated COX-2 and HMLH1 genes were associated with H. pylori vacA s1 (p = 0.025 and 0.047, respectively), and the nonmethylated tumors were associated with the presence of the gene flaA. CONCLUSIONS: These data suggest that the inactivation of these genes by methylation occurs by distinct pathways according to the histological subtype and tumor location and depends on the H. pylori genotype.

Detection of deletions in 1q25, 1p36 and 1pTEL and chromosome 17 aneuploidy in oral epithelial dysplasia and oral squamous cell carcinoma by fluorescence in situ hybridization (FISH).

OBJECTIVE: To identify chromosome deletions in 1q25, 1p36 and 1pTEL, and chromosome 17 ploidy status in oral epithelial dysplasia (OED) and oral squamous cell carcinoma (OSCC). MATERIAL AND METHODS: Samples from 57 OED and 63 OSCC were selected. FISH was performed using centromeric probes 17 and n LSIR 1p36/LSI 1q25 Dual Color Probe. RESULTS: In OED, deletions were found only in 1pTEL region (29.8%). In OSCC, there was a higher frequency of deletion in 1pTEL (79.4%), followed by 1p36 (73.0%), and 1q25 (20.6%). Advanced TNM clinical stages (III/IV) showed all the deletions studied; at early clinical stages (I/II) of OSCC, deletions were observed only in 1pTEL. The frequency of deletion in 1p36 was 17.0 times higher in OSCC at advanced clinical stages (PR: 17.00). The median number of cell nuclei with chromosome 17 aneuploidy was higher in OSCC than in OED (P < 0.001). Early clinical stages of OSCC showed lower median number nuclei with aneuploidy when compared to advanced tumors (P < 0.05). Tumors harboring deletions in 1p36, 1q25 and 1pTEL revealed higher median numbers of trisomic/polysomic nuclei when compared to lesions exhibiting no abnormalities in chromosome 1 (P < 0.05). CONCLUSION: A higher prevalence of chromosomal abnormalities was found in OSCC than in OED, while in OSCC, higher abnormalities were present in lesions with higher TNM staging. 1pTEL deletion and monosomy of chromosome 17 are possible markers for progression of OED to OSCC. 1p36 deletion and trisomy/polysomy of chromosome 17 could be markers of worse prognosis of OSCC.