CRISTINA MENDES DE OLIVEIRA
Projetos de Pesquisa
Unidades Organizacionais
LIM/52 - Laboratório de Virologia, Hospital das Clínicas, Faculdade de Medicina
5 resultados
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- Low mutation percentage of KRAS and BRAF genes in Brazilian anal tumors(2016) BIDINOTTO, Lucas Tadeu; VEO, Carlos A. R.; LOAIZA, Edgar Aleman; FRANCA, Alessandra Paulino Santos De; LORENZI, Adriana Tarla; ROSA, Luciana Albina Reis; OLIVEIRA, Cristina Mendes De; LEVI, Jose Eduardo; SCAPULATEMPO-NETO, Cristovam; LONGATTO-FILHO, Adhemar; REIS, Rui ManuelAnal cancer is a rare type of digestive tract disease, which has had a crescent incidence in a number of regions. Carcinomas are most frequently found, with squamous cell carcinoma (SCC) comprising similar to 95% of all anal tumors. The major risk factor for development of this type of tumor is human papillomavirus (HPV) infection. However, previous studies have identified patients with anal cancer that are HPV-/p16-and observed that they have a poorer outcome compared with HPV+/p16+ patients. This suggests that molecular profile may drive anal cancer progression. The aim of the present study was to evaluate the mutational status of two important oncogenes, KRAS and BRAF, in a series of anal cancer lesions. Resected tumors of the anal canal (n=43) were evaluated, nine of these were high-grade squamous intra-epithelial lesion cases (HSIL), 11 were adenocarcinomas, and 23 SCCs. Direct sequencing of KRAS proto-oncogene, GTPase (KRAS; codons 12 and 13) and B-Raf proto-oncogene, serine/threonine kinase (BRAF; codon 600) was performed and associated with patient clinicopathological and molecular features. There was a trend of poorer prognosis of adenocarcinoma compared with HSIL and SCC. Analysis indicated one SCC patient (2.3%) exhibited a KRAS p.G13D mutation, and one adenocarcinoma patient (2.3%) exhibited a BRAF p.V600E mutation. It was observed that, these mutations are rare in anal tumors, and certain patients may be at a disadvantage using targeted therapies based on KRAS and BRAF mutational status. As there is a low mutation percentage in SCCs, adenocarcinomas and HSIL, there may exist other underlying molecular alterations that result in anal cancer development, which require further elucidation.
- Angiosarcoma in HIV-negative patients is not associated with HHV-8(2016) AVANCINI, Joao; CHERUBIM, Andre Pires Zanata; OLIVEIRA, Cristina Mendes de; VALENTE, Neusa Yuriko Sakai; FESTA NETO, Cyro; SANCHES, Jose Antonio; PAZZINI, Renato; SUMITA, Laura Masami; PANNUTI, Claudio SergioBACKGROUND: Angiosarcoma is an aggressive, malignant neoplasm of vascular or lymphatic origin. Herpes virus 8 (HHV-8) is a member of the herpes family with a tropism for endothelial cells and it has been proven to induce vascular neoplasms, such as Kaposi's sarcoma. The role of HHV-8 in the pathogenesis of angiosarcoma has not been well defined. OBJECTIVE: To investigate the relationship between the presence of HHV-8 and angiosarcoma. METHODS: In this study, the team investigated the relationship between the presence of HHV-8, as determined by polymerase chain reaction, and angiosarcoma, using samples from patients with epidemic Kaposi's sarcoma as controls. RESULTS: While all control cases with epidemic Kaposi's sarcoma were positive for HHV-8, none of the angiosarcoma cases was. CONCLUSION: These findings support most previous studies that found no association between HHV-8 and angiosarcoma.
- HPV genotype distribution in Brazilian women with and without cervical lesions: correlation to cytological data(2016) MARTINS, Toni Ricardo; OLIVEIRA, Cristina Mendes de; ROSA, Luciana Reis; CENTRONE, Cristiane de Campos; RODRIGUES, Celia Luiza Regina; VILLA, Luisa Lina; LEVI, Jose EduardoBackground: Human Papillomavirus (HPV) genotype distribution varies according to the method of assessment and population groups. This study analyzed type-specific HPV infections among women ranging from 14-95 years old, displaying normal and abnormal cytology, from Sao Paulo and Barretos cities, Brazil. Methods: Women found positive for High Risk-HPVs DNA by either the Hybrid Capture 2 (HC2) or Cobas HPV Test (n = 431) plus a random sample of 223 negative by both assays and 11 samples with indeterminate results, totalizing 665 samples, were submitted to HPV detection by the PapilloCheck test. Cytological distribution included 499 women with a cytological result of Negative for Intraepithelial Lesion or Malignancy and 166 with some abnormality as follows: 54 Atypical Squamous Cells of Undetermined Significance; 66 Low-Grade Squamous Intraepithelial Lesion; 43 High-Grade Squamous Intraepithelial Lesion and 3 (0.5 %) Invasive Cervical Cancer. Results: From the 323 samples (48.6 %) that had detectable HPV-DNA by the PapilloCheck assay, 31 were HPV negative by the cobas HPV and HC2 assays. Out of these 31 samples, 14 were associated with HR-HPVs types while the remaining 17 harbored exclusively low-risk HPVs. In contrast, 49 samples positive by cobas HPV and HC 2 methods tested negative by the PapilloCheck assay (19.8 %). Overall, the most frequent HR-HPV type was HPV 16 (23.2 %), followed by 56 (21.0 %), 52 (8.7 %) and 31 (7.7 %) and the most frequent LR-HPV type was HPV 42 (12.1 %) followed by 6 (6.2 %). Among the HR-HPV types, HPV 56 and 16 were the most frequent types in NILM, found in 19. 1 and 17.7 % of the patients respectively while in HSIL and ICC cases, HPV 16 was the predominant type, detected in 37.2 and 66.7 % of these samples. Conclusions: In the population studied, HPV 16 and 56 were the most frequently detected HR-HPV types. HPV 56 was found mainly in LSIL and NILM suggesting a low oncogenic potential. HPV 16 continues to be the most prevalent type in high-grade lesions whereas HPV 18 was found in a low frequency both in NILM and abnormal smears. Surveillance of HPV infections by molecular methods is an important tool for the development and improvement of prevention strategies.
- Genotypic distribution of HHV-8 in AIDS individuals without and with Kaposi sarcoma Is genotype B associated with better prognosis of AIDS-KS?(2016) TOZETTO-MENDOZA, Tania Regina; IBRAHIM, Karim Yaqub; TATENO, Adriana Fumie; OLIVEIRA, Cristiane Mendes de; SUMITA, Laura Massami; SANCHEZ, Maria Carmem Arroyo; LUNA, Expedito Jose; PIERROTTI, Ligia Camara; DREXLER, Jan Felix; BRAZ-SILVA, Paulo Henrique; PANNUTI, Claudio Sergio; ROMANO, Camila MaltaAIDS-associated Kaposi's sarcoma (AIDS-KS) caused by human herpes virus 8 (HHV-8) is the most severe and resistant form of KS tumor. Our aim was to verify whether there is an association between HHV-8 variability and development of AIDS-KS in Brazil by comparing the HHV-8 variability between individuals without and with KS. Saliva samples and blood, when available, were analyzed by PCR techniques for detection of the fragments of ORF K1 of HHV-8, which were then genotyped and analyzed regarding the genetic variability. Our study described 106 positive cases for HHV-8 in the saliva from 751 AIDS patients without previous KS. In addition, we performed a phylogenetic analysis of HHV-8 in 34 of the 106 AIDS patients without KS and in 33 of the 37 patients with active KS. The distribution of HHV-8 genotypes A, B, C, and F in AIDS individuals was indistinguishable by comparing non-KS and KS groups, as well as regarding ethnicity. Considering the KS group, genotype B was associated with better prognosis of KS tumor. Interestingly. we found a particular profile of diversity within Glade C and 2 recombinant patterns of HHV-8 in the saliva of AIDS individuals without KS. We emphasize the need to achieve standard genotyping protocol for ORF K1 amplification, thus allowing for substantial detection of HHV-8 variants. Our findings can shed light on the role of HHV-8 variability in the pathogenesis of AIDS-KS.
- The Biological Impact of Genomic Diversity in Cervical Cancer Development(2016) OLIVEIRA, Cristina Mendes de; LEVI, Jose EduardoHuman papillomaviruses (HPVs) are the etiologic agents of cervical cancer, the unique human neoplasia that has one single necessary cause. The diversity of HPVs is well described, with 200 HPV types existing as distinct taxonomic units and each receiving an Arabic number. On a clinical basis, they are usually grouped by their site of occurrence and disease associations. Those types inhabiting the anogenital mucosa are more intensively studied and further divided into cancer-associated HPVs, which are termed 'high risk', while those linked to benign proliferative lesions are assigned as 'low risk'. HPV16 is responsible for approximately 50% of all ICC cases, and paradoxically is one of the most prevalent types among healthy women. Longitudinal studies have shown that when an incidental HPV16 infection becomes persistent it will result in an enhanced risk for the development of high-grade lesions. However, it is unknown why some persistent, HPV16 infections (or infections by other HR-HPV types) progress to CIN3+ while most clear spontaneously. Several epidemiological investigations have focused on cofactors, from the most obvious such as cigarette and other carcinogenic exposures, to coinfections by other STDs such as chlamydia, with no significant findings. Thus, the current focus is on genomic variation from both virus and host. Such studies have been potentialized by the enormous technical advances in nucleic acid sequencing, allowing this relationship to be broadly interrogated. Corroborating subgenomic data from decades ago, an association between HPV16 lineages and carcinogenesis is being revealed. However, this effect does not seem to apply across female populations from different continents/ethnicities, again highlighting a role played by HPV16 adaptation and evasion from the host over time. (C) 2016 S. Karger AG, Basel.