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Featured researches published by Cláudio Osmar Pereira Alexandre.


Breast Cancer Research and Treatment | 2004

Evidence for an association of human papillomavirus and breast carcinomas

Andrea Pires Souto Damin; Rachid Karam; Cláudio Galleano Zettler; Maira Caleffi; Cláudio Osmar Pereira Alexandre

Human papillomavirus (HPV) DNA has been detected in breast carcinoma by different laboratorial techniques, suggesting the virus could play a role in the pathogenesis of this tumor. The aim of the present study is to investigate the presence of HPV in patients with breast carcinoma and the correlation of the viral infection with prognostic factors for the disease outcome. Between June 2001 and July 2002, 101 paraffin embedded breast carcinoma specimens were analyzed through polymerase chain reaction (PCR) and sequencing of HPV-E6 gene. Twenty specimens of reduction mammoplasty and 21 specimens of fibroadenomas were also studied as a non-malignant control group. Two different specific primer sets targeting E6 region of the HPVs 16 and 18 were used for the analysis. The HPV DNA was detected in 25 breast carcinomas (24.75%), but in none of the benign breast specimens (p < 0.001). Out of the 25 positive cases, 14 were HPV-16 positive (56%) and 10 were HPV-18 positive (40%). An original finding was the detection of both HPV-16 and -18 in a single tumor (4%). The amplified viral sequences confirmed the presence of HPV-16 and -18. No correlation between the presence of HPV DNA and specific prognostic predictors for the disease outcome was observed. Our results suggest that the presence in the breast of either HPV-16 or -18 might be related to development of the malignant phenotype. Further studies are warranted.


Cancer Genetics and Cytogenetics | 2010

Polymorphism (ALA16VAL) correlates with regional lymph node status in breast cancer

Claudia Giuliano Bica; Leonardo Leiria de Moura da Silva; Nadima Vieira Toscani; Cláudio Galleano Zettler; Maria Gabriela Valle Gottlieb; Cláudio Osmar Pereira Alexandre; Márcia Silveira Graudenz; Ivana Beatrice Mânica da Cruz

We studied the possible association between Ala16Val manganese-dependent superoxide dismutase (MnSOD) gene genotypes and breast cancer lymph node status because previous investigations suggested an association between the AA genotype and breast cancer. We included 281 women (188 controls and 93 cases of invasive breast cancer with axillary lymph node metastasis (LN+) and without lymph node metastasis (LN-). DNA was extracted from paraffin-embedded tumor tissue or peripheral blood leukocytes, and MnSOD polymorphism was determined by polymerase chain reaction-restriction fragment length polymorphism techniques. In addition, the immunohistochemical profile (p53, Ki-67 and estrogen/progesterone receptors) was also compared between invasive breast cancer groups and different MnSOD genotypes. The frequency of the VV genotype was higher in the LN+ group than in the control and LN- groups (chi(2)=5.081, P=0.02). Subjects with LN+ breast cancer (LN+ group) showed a higher incidence of VV genotype carriers associated with positive Ki-67 marker. Subjects with LN+ breast cancer (LN+ group) showed a higher incidence of VV genotype carriers associated with negative p53 marker. Despite the fact that the AA genotype is well established as being associated with an increased risk of breast cancer, the VV genotype may be associated with a higher metastatic potential, suggesting that MnSOD imbalance is the condition associated with carcinogenesis.


Pathology & Oncology Research | 2005

Expression of Ki-67 and squamous intraepithelial lesions are related with HPV in endocervical adenocarcinoma.

Eduardo Cambruzzi; Cláudio Galleano Zettler; Cláudio Osmar Pereira Alexandre

To estimate the association between human papillomavirus (HPV) status and the expression of p53, Ki-67 and bcl-2 in cases of endocervical adenocarcinoma, and the relation with squamous intraepithelial lesions (SIL) and age, 229 cases were selected, treated between 1995 and 2003 in the Hospital Nossa Senhora da Conceição. All samples were evaluated by polymerase chain reaction to determine HPV status. Immunohistochemical technique was used to investigate the expression of p53, Ki-67 and bcl-2. The joint occurrence of endocervical adenocarcinoma and SIL were estimated too. In the 229 evaluated cases, 182 cases (79.48%) were associated with the presence of the HPV. The most common types were HPV18 (93 cases-51.09%) and HPV16 (62 cases-34.06%). Expression of Ki-67 (p=0.009) and the presence of SIL (p=0.018) were associated to HPV infection. Expression of p53 (p=0.647) and bcl-2 (p=0.671) were not related to HPV status. The mean age of the patients was 53.2 years, without clear correlation between age group and HPV (p=0.095). The presence of HPV, especially type 18 in endocervical adenocarcinoma suggests that this agent can be an important cofactor in the development and progression of glandular neoplasms of the uterine cervix. The joint occurrence of endocervical adenocarcinoma and SIL may support this hypothesis. HPV may promote an increased proliferation index in endocervical adenocarcinoma, shown by the expression of Ki-67.


Arquivos De Gastroenterologia | 2006

Prevalence of the hemochromatosis gene mutation in patients with nonalcoholic steatohepatitis and correlation with degree of liver fibrosis

Idilio Zamin; Angelo Alves de Mattos; Ângelo Zambam de Mattos; Eduardo Migon; Claudia Giuliano Bica; Cláudio Osmar Pereira Alexandre

BACKGROUND Nonalcoholic steatohepatitis is a chronic liver disease with a high prevalence in the general population and a potential to evolve into cirrhosis. It is speculated that iron overload could be associated with liver injury and unfavorable progress in affected patients. AIMS To evaluate the prevalence of mutation of the hemochromatosis gene (HFE) in patients with nonalcoholic steatohepatitis and to correlate it with histological findings in liver specimens. PATIENTS AND METHODS Twenty-nine patients with nonalcoholic steatohepatitis were evaluated. The presence of mutation in the hemochromatosis gene (C282Y and H63D) was tested in all patients and its result was evaluated in relation to hepatic inflammatory activity, presence of fibrosis, and iron overload in the liver. The control group was composed of 20 patients with normal liver function tests and 20 patients infected with the hepatitis C virus, with elevated serum levels of aminotransferases and with chronic hepatitis as shown by biopsy. RESULTS Mutation of the hemochromatosis gene (C282Y and/or H63D) was diagnosed in 16 (55.2%) patients with nonalcoholic steatohepatitis, in 12 (60%) patients with hepatitis C and in 8 (40%) patients with no liver disease. No association was found between the presence of mutation and inflammatory activity, nor with the presence of fibrosis in patients with nonalcoholic steatohepatitis. An association was found between the presence of mutation and the occurrence of iron overload in liver, but there was no association between liver iron and the occurrence of fibrosis. CONCLUSIONS The findings suggest that iron does not play a major role in the pathogenesis and progression of nonalcoholic steatohepatitis, and routine tests of the hemochromatosis gene mutation in these patients should not be recommended.


Clinical Chemistry and Laboratory Medicine | 2013

Elevated level of cell-free plasma DNA is associated with advanced-stage breast cancer and metastasis

Carmela Nicolini; Cíntia Ens; Talita Cerutti; Adriana Roehe; Grasiela Agnes; Andrea Pires Souto Damin; Cláudio Osmar Pereira Alexandre

*Corresponding author: Adriana Vial Roehe, Department of Pathology, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Rua Sarmento Leite, 245. Porto Alegre, RS 90050170, Brazil, Phone: +55 51 32394000, Fax: +55 51 33038810, E-mail: [email protected] Carmela Nicolini, Cíntia Ens, Grasiela Agnes and Cláudio O.P. Alexandre: Laboratory of Molecular Biology, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Porto Alegre, RS, Brazil Talita Cerutti and Andréa P.S. Damin: Division of Breast Surgery, Hospital Fêmina, Grupo Hospitalar Conceição, Porto Alegre, RS, Brazil


Ejso | 2007

Evidence for an association of human papillomavirus infection and colorectal cancer

Daniel de Carvalho Damin; M.B. Caetano; Mario Antonello Rosito; Gilberto Schwartsmann; A.S. Damin; A.P. Frazzon; R.D. Ruppenthal; Cláudio Osmar Pereira Alexandre


Cancer Detection and Prevention | 2006

Evidence for an association of TP53 codon 72 polymorphism with breast cancer risk

Andrea Pires Souto Damin; Ana Paula G Frazzon; Daniel C. Damin; Adriana Roehe; Vanessa Hermes; Cláudio Galleano Zettler; Cláudio Osmar Pereira Alexandre


The Breast | 2007

HPV infection and breast cancer

Andrea Pires Souto Damin; Daniel de Carvalho Damin; Cláudio Osmar Pereira Alexandre


Archives of Gynecology and Obstetrics | 2015

Prevalence of human papillomavirus infection in pregnant versus non-pregnant women in Brazil.

Mila Pontremoli Salcedo; Andrea Pires Souto Damin; Grasiela Agnes; Suzana Arenhart Pessini; Patrícia El Beitune; Cláudio Osmar Pereira Alexandre; Kathleen M. Schmeler; Gustavo Py Gomes da Silveira


World Journal of Gastroenterology | 2009

Lack of correlation between p53 codon 72 polymorphism and anal cancer risk.

Simone Santana Contu; Grasiela Agnes; Andrea Pires Souto Damin; Paulo de Carvalho Contu; Mario Antonello Rosito; Cláudio Osmar Pereira Alexandre; Daniel de Carvalho Damin

Collaboration


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Andrea Pires Souto Damin

Laboratory of Molecular Biology

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Daniel de Carvalho Damin

Universidade Federal do Rio Grande do Sul

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Adriana Roehe

Laboratory of Molecular Biology

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Grasiela Agnes

Laboratory of Molecular Biology

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Angelo Alves de Mattos

Universidade Federal de Ciências da Saúde de Porto Alegre

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Claudia Giuliano Bica

Universidade Federal de Ciências da Saúde de Porto Alegre

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Mario Antonello Rosito

Universidade Federal do Rio Grande do Sul

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Poliana Leopoldino Ansolin

Universidade Federal de Ciências da Saúde de Porto Alegre

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Eduardo Cambruzzi

Universidade Federal do Rio Grande do Sul

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