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Browsing by Author "Botelho, M.C."

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  • Angiogenesis in Schistosoma haematobium-associated urinary bladder cancer
    Publication . Dematei, A.; Fernandes, R.; Soares, R.; Alves, H.; Richter, J.; Botelho, M.C.
    Schistosoma haematobium, a parasitic flatworm that infects more than 100 million people, mostly in the developing world, is the causative agent of urogenital schistosomiasis, and is associated with a high incidence of squamous cell carcinoma (SCC) of the bladder. During infection, eggs are deposited in the bladder causing an intense inflammatory reaction. Angiogenesis is defined as the formation of new blood vessels from preexisting ones and is recognized as a key event in cell proliferation and carcinogenesis and spread of malignant lesions. A growing amount of evidence points to angiogenesis playing a key role in schistosomiasis-associated bladder cancer. Thus, identifying biomarkers of this process plays an important role in the study of cancer. Here, we review recent findings on the role of angiogenesis in bladder cancer and the growth factors that induce and assist in their development, particularly SCC of the bladder associated to urogenital schistosomiasis.
    2017-12Journal article Restricted access Show more
  • Anti-cancer potential of Fasciola hepatica extracts
    Publication . Ferreira, S.; Fernandes, R.; Alves, H.; Richter, J.; Botelho, M.C.
    Fascioliasis is a food borne disease caused by infection with a liver fluke termed Fasciola (F.) hepatica. Fascioliasis, as a neglected tropical disease, commonly affects poor people from developing countries. It has been estimated that at least 2.6 million people are infected with fascioliasis worldwide. According to the International Agency for Research on Cancer, two other liver flukes Opistorchis viverrini and Clonorchis sinensis) have been recognized as definitive causes of cancer (IARC, 2012). On the other hand even long-lasting and/ or repeated F. hepatica infections have not been associated with cancer, so far. There are any known causative associations between this parasite and cholangiocarcinoma or liver cancer.
    2017-10Conference object Open access Show more
  • Bladder cancer and urinary Schistosomiasis in Angola
    Publication . Botelho, M.C.; Figueiredo, J.; Alves, H.
    Schistosomiasis haematobia is among the most prevalent parasitosis in Angola. The pathology is characterized by serious and irreversible lesions in the urogenital tract induced by chronic infection with the parasite that can eventually lead to squamous cell carcinoma of the bladder. Considering the frequency and severe morbidity observed, even in younger ages, the purpose of this study was to assess the prevalence and morbidity of S. haematobium infection in Angola. A baseline survey was conducted between November 2007 and February 2008. A randomly sample of 300 inhabitants aged 15 to 75 years old participated in this study. Prevalence of S. haematobium infection was 71.7 % (215/300). Infection was higher in females (56.3 %) but no significant difference was found in prevalence and intensity between gender and age groups. The predominant selfreported symptoms were dysuria (91.2 %), hypogastralgia (88.7 %) and haematuria (87.1%) and these symptoms were strongly associated with S. haematobium infection (p<0.05). Ultrasound and cystoscopy examinations performed in a sub-sample of 29 individuals revealed pathological conditions at the urinary tract in all examined. Considering the high prevalence of S. haematobium infections in Angola and schistosomiasis-associated bladder cancer, our results indicate that this population should be targeted for follow up and implementation of measures for treatment and control of schistosomiasis.
    2015-06Journal article Open access Show more
  • CYP2D6 and IL-6 C-174G variants in schistosomiasis haematobia
    Publication . Cardoso, R.; Alves, H.; Bordalo, A.; Richter, J.; Botelho, M.C.
    Aim: Study polymorphic variants in CYP2D6 and the C-174G promoter polymorphism of the IL-6 gene on S. haematobium infected patients from and endemic area of Guinea Bissau. Background: - Schistosome egg associated catechol estrogens induce tumor-like phenotypes in urothelial cells and might cause schistosomiasis associated infertility (Botelho et al, Trends in Parasitol, 2015); - The cytochrome P450 (CYP) genes are involved in estrogen biosynthesis and metabolism and generation of DNA damaging procarcinogens (Blackburn et al, Cancer Causes and Control, 2015); - Very high or very low levels of IL-6 are associated with estrogen metabolism imbalance.
    2016-11Conference object Open access Show more
  • CYP2D6 and IL-6 c-174G variants in schistosomiasis haematobia
    Publication . Cordeiro, R.; Alves, H.; Bordalo, A.; Richter, J; Botelho, M.C.
    AIM: To study the polymorphic variants in CYP2D6 and the C-174G promoter polymorphism of the IL-6 gene on S. haematobium infected patients from an endemic area of Guinea Bissau. BACKGROUND: - Our group has shown that schistosome egg associated catechol estrogens induce tumor-like phenotypes in urothelial cells. These estrogen metabolites might also be the cause of schistosomiasis associated infertility; - The cytochrome P450 (CYP) genes are oxygenases involved in estrogen biosynthesis and metabolism, generation of DNA damaging procarcinogens, and response to anti-estrogen therapies; - IL6 Interleukin-6 (IL-6) is a pleiotropic cytokine expressed in many tissues. These cytokine is largely expressed in female urogenital tract as well as reproduction organs. Very high or very low levels of IL-6 are associated with estrogen metabolism imbalance.
    2016-11Conference object Open access Show more
  • 2013-04Conference object Open access Show more
  • Effects of titanium dioxide nanoparticles in human gastric epithelial cells in vitro
    Publication . Botelho, M.C.; Costa, C.; Silva, S.; Costa, S.; Dhawan, A.; Oliveira, P.A.; Teixeira, João Paulo
    Manufacturing or using nanomaterials may result in exposure of workers to nanoparticles. Potential routes of exposure include skin, lung and gastrointestinal tract. The lack of health-based standards for nanomaterials combined with their increasing use in many different workplaces and products emphasize the need for a reliable temporary risk assessment tool. Therefore, the aim of this work was to explore the effects of different doses of titanium dioxide nanoparticles on human gastric epithelial cells in vitro. We analyzed proliferation by MTT assay, apoptosis by Tunel, migration by injury assay, oxidative stress by determining GSH/GSSG ratio and DNA damage by Comet assay on nanoparticle-treated AGS human gastric epithelial cell line in comparison to controls. We show and discuss the tumor-like phenotypes of nanoparticles-exposed AGS cells in vitro, as increased proliferation and decreased apoptosis. Our results demonstrate for the first time that nanoparticles induce tumor-like phenotypes in human gastric epithelial cells.
    2013-08-23Journal article Restricted access Show more
  • Endothelial Progenitor Cells in Breast Cancer
    Publication . Botelho, M.C.; Alves, H.
    Recent evidences demonstrated the importance of bone marrow derived Endothelial Progenitor Cells (EPC), in the contribution to postnatal physiological and pathological neovascularization, and in tumor growth and angiogenesis. These cells are recruited undifferentiated, in response to systemic or chemoatractive signals, such as Vascular Endothelial Growth Factor (VEGF), they lodge in the growing or lesioned tissue and differentiate into endothelial cells in response to local stimuli and cell-cell interactions. The extent and the significance of the EPCs contribution for the growing of most tumors, including those of the breast, are still not fully defined. We analyzed the peripheral blood of breast cancer patients and found that they have circulating EPCs. We also found an association between expression of AC133+Kdr+ and VEGF plasma levels in these patients. Strategies to impair the mobilization and incorporation of EPCs into breast tumors may contribute to halt the growth of these tumors.
    2016-01-23Journal article Open access Show more
  • Epidemiology and pathology of bovine schistosomiasis in Mozambique
    Publication . Botelho, M.C.; Ferreira, M.L.; Oliveira, P.; Alves, H.; Richter, J.
    AIM: To study the epidemiology and pathology of bovine schistosomiasis in Mozambique. BACKGROUND: - Bovine schistosomiasis is of great importance in Africa. It is caused by Schistosoma bovis; - In bovines the symptoms are similar to humans, mainly intestinal, hepato-splenic, vesical and genital; - It has been shown to be endemic through all Africa and in some Mediterranean countries (Portugal, Spain, Italy, Iraque and Israel); - Hybrids of S. haematobium and S. bovis are known to infect humans.
    2016-11Conference object Open access Show more
  • Estrogen catechols detection as biomarkers in schistosomiasis induced cancer and infertility
    Publication . Botelho, M.C.; Alves, H.; Richter, J.
    Urogenital schistosomiasis is a chronic infection caused by the human blood fluke Schistosoma haematobium. Schistosomiasis haematobium is a known risk factor for cancer leading to squamous cell carcinoma of the urinary bladder (SCC). This is a neglected tropical disease endemic in many countries of Africa and the Middle East. Schistosome eggs produce catechol-estrogens. These molecules are metabolized to active quinones that cause alterations in DNA (leading in other contexts to breast or thyroid cancer). Our group have shown that schistosome egg associated catechol estrogens induce tumor-like phenotypes in urothelial cells, originated from parasite estrogen-host cell chromosomal DNA adducts and mutations. Here we review recent findings on the role of estrogen-DNA adducts and how their shedding in urine may be prognostic of schistosome infection and/or represent potential biomarkers for urogenital schistosomiasis associated bladder cancer and infertility.
    2017-01Journal article Open access Show more