Tumour-like phenotypes in urothelial cells after exposure to antigens from eggs of Schistosoma haematobium: an oestrogen-DNA adducts mediated pathway?

Mass spectrometry based metabolomics for small molecule metabolites mining and confirmation as potential biomarkers for schistosomiasis - case of the Okavango Delta communities in Botswana

INTRODUCTION

Metabolomics for identifying schistosomiasis biomarkers in noninvasive samples at various infection stages is being actively explored. The literature on the traditional detection of schistosomiasis in human specimens is well documented. However, state-of-the-art technologies based on mass spectrometry have simplified the use of biomarkers for diagnostics. This review examines methods currently in use for the metabolomics of small molecules using separation science and mass spectrometry.

AREA COVERED

This article highlights the evolution of traditional diagnostic methods for schistosomiasis based on inter alia microscopy, immunology, and polymerase chain reaction. An exhaustive literature search of metabolite mining, focusing on separation science and mass spectrometry, is presented. A comparative analysis of mass spectrometry methods was undertaken, including a projection for the future.

EXPERT COMMENTARY

Mass spectrometry metabolomics for schistosomiasis will lead to biomarker discovery for noninvasive human samples. These biomarkers, together with those from other neglected tropical diseases, such as malaria and sleeping sickness, could be incorporated as arrays on a single biosensor chip and inserted into smartphones, in order to improve surveillance, monitoring, and management.

Pancreatic Leiomyosarcoma With Schistosomiasis Hematobia: A Case Report and Literature Review

Pancreatic leiomyosarcoma (PL) is a very rare, malignant neoplasm with a very poor prognosis. Here, we examine a novel case of PL with schistosomiasis hematobia. The patient had been initially misdiagnosed by the first magnetic resonance imaging (MRI). The second imaging examination demonstrated an enlarged heterogeneous tumor mass in the body-tail of pancreas. Following image analysis, the patient underwent a pancreatectomy, splenectomy and lymph node dissections. Sixteen months after the tumor resection, follow-up computed tomography (CT) and MRI revealed tumor metastasis in the liver and lung. PL has non-specific clinical manifestations and imaging characteristics, making early diagnosis very challenging. When it is difficult to distinguish between benign and malignant pancreatic lesions, short-term imaging follow-up is preferred. In this case report, we discuss the relationship between PL and schistosomiasis hematobia.

Control Strategies for Carcinogenic-Associated Helminthiases: An Integrated Overview

Helminthiases are extremely prevalent in the developing world. In addition, the chronic infection with some parasitic worms are classified as carcinogenic. Therefore, it is utmost importance to understand the parasite-host interactions, the mechanisms underlay carcinogenesis and how they could be counteracted. This knowledge may ultimately guide novel control strategies that include chemotherapy-based approaches targeting these pathogens and associated pathologies caused by their infections. Little is known on how some helminthiases are associated with cancer; however, it has been hypothesized that chemical carcinogenesis may be involved in the process. Here, we summarize the current knowledge on chemical carcinogenesis associated with helminthiases, along with available therapeutic options and potential therapeutic alternatives including chemotherapy and/or immunotherapy. Ideally, the treatment of the carcinogenic helminthiases should target both the parasite and associated pathologies. The success of any chemotherapeutic regimen often depends on the host immune response during the infection and nutritional status among other factors. The close association between chemotherapy and cell-mediated immunity suggests that a dual therapeutic approach would be advantageous. In addition, there is a pressing need for complementary drugs that antagonize the carcinogenesis process associated with the helminth infections.

Urogenital Schistosomiasis-History, Pathogenesis, and Bladder Cancer

Schistosomiasis is the most important helminthiasis worldwide in terms of morbidity and mortality. Most of the infections occurs in Africa, which about two thirds are caused by Schistosoma haematobium. The infection with S. haematobium is considered carcinogenic leading to squamous cell carcinoma (SCC) and urothelial carcinoma of the urinary bladder. Additionally, it is responsible for female genital schistosomiasis leading to infertility and higher risk of human immunodeficiency virus (HIV) transmission. Remarkably, a recent outbreak in Corsica (France) drew attention to its potential re-mergence in Southern Europe. Thus far, little is known related to host-parasite interactions that trigger carcinogenesis. However, recent studies have opened new avenues to understand mechanisms on how the parasite infection can lead cancer and other associated pathologies. Here, we present a historical perspective of schistosomiasis, and review the infection-associated pathologies and studies on host-parasite interactions that unveil tentative mechanisms underlying schistosomiasis-associated carcinogenesis.

IPSE, an abundant egg-secreted protein of the carcinogenic helminth Schistosoma haematobium, promotes proliferation of bladder cancer cells and angiogenesis

BACKGROUND

Schistosoma haematobium, the helminth causing urogenital schistosomiasis, is a known bladder carcinogen. Despite the causal link between S. haematobium and bladder cancer, the underlying mechanisms are poorly understood. S. haematobium oviposition in the bladder is associated with angiogenesis and urothelial hyperplasia. These changes may be pre-carcinogenic events in the bladder. We hypothesized that the Interleukin-4-inducing principle of Schistosoma mansoni eggs (IPSE), an S. haematobium egg-secreted "infiltrin" protein that enters host cell nuclei to alter cellular activity, is sufficient to induce angiogenesis and urothelial hyperplasia. Methods: Mouse bladders injected with S. haematobium eggs were analyzed via microscopy for angiogenesis and urothelial hyperplasia. Endothelial and urothelial cell lines were incubated with recombinant IPSE protein or an IPSE mutant protein that lacks the native nuclear localization sequence (NLS-) and proliferation measured using CFSE staining and real-time monitoring of cell growth. IPSE's effects on urothelial cell cycle status was assayed through propidium iodide staining. Endothelial and urothelial cell uptake of fluorophore-labeled IPSE was measured. Findings: Injection of S. haematobium eggs into the bladder triggers angiogenesis, enhances leakiness of bladder blood vessels, and drives urothelial hyperplasia. Wild type IPSE, but not NLS-, increases proliferation of endothelial and urothelial cells and skews urothelial cells towards S phase. Finally, IPSE is internalized by both endothelial and urothelial cells. Interpretation: IPSE drives endothelial and urothelial proliferation, which may depend on internalization of the molecule. The urothelial effects of IPSE depend upon its NLS. Thus, IPSE is a candidate pro-carcinogenic molecule of S. haematobium.

SUMMARY

Schistosoma haematobium acts as a bladder carcinogen through unclear mechanisms. The S. haematobium homolog of IPSE, a secreted schistosome egg immunomodulatory molecule, enhances angiogenesis and urothelial proliferation, hallmarks of pre-carcinogenesis, suggesting IPSE is a key pro-oncogenic molecule of S. haematobium.

Current and Novel Therapies Against Helminthic Infections: The Potential of Antioxidants Combined with Drugs

Infections caused by Schistosoma haematobium and Opisthorchisviverrini are classified as Group 1 biological carcinogen and it has been postulated that parasites produce oxysterol and estrogen-like metabolites that might be considered as initiators of infection-associated carcinogenesis. Chemotherapy for these helminthic infections relies on a single drug, praziquantel, (PZQ) that mainly targets the parasite. Additionally, PZQ has some major drawbacks as inefficacy against juvenile form and alone it is not capable to counteract pathologies associated to infections or prevent carcinogenesis. There is an urgent need to develop novel therapeutic approaches that not only target the parasite but also improve the pathologies associated to infection, and ultimately, counteract or/and prevent the carcinogenesis processes. Repurposing the drug in combination of compounds with different modes of action is a promising strategy to find novel therapeutics approaches against these helminthic infections and its pathologies. Here, we emphasized that using antioxidants either alone or combined with anthelmintic drugs could ameliorate tissue damage, infection-associated complications, moreover, could prevent the development of cancer associated to infections. Hence, antioxidants represent a potential adjuvant approach during treatment to reduce morbidity and mortality. Despite the success of some strategies, there is a long way to go to implement novel therapies for schistosomiasis.

Neglected Agent Eminent Disease: Linking Human Helminthic Infection, Inflammation, and Malignancy

Helminthic parasitic infection is grossly prevalent across the globe and is considered a significant factor in human cancer occurrence induced by biological agents. Although only three helminths (Schistosoma haematobium, Clonorchis sinensis, and Opisthorchis viverrini) so far have been directly associated with carcinogenesis; there are evidence suggesting the involvement of other species too. Broadly, human helminthiasis can cause chronic inflammation, genetic instability, and host immune modulation by affecting inter- and intracellular communications, disruption of proliferation-anti-proliferation pathways, and stimulation of malignant stem cell progeny. These changes ultimately lead to tumor development through the secretion of soluble factors that interact with host cells. However, the detailed mechanisms by which helminths introduce and promote malignant transformation of host cells are still not clear. Here, we reviewed the current understanding of immune-pathogenesis of helminth parasites, which have been associated with carcinogenesis, and how these infections initiate carcinogenesis in the host.

Infection with carcinogenic helminth parasites and its production of metabolites induces the formation of DNA-adducts

Background

Infections classified as group 1 biological carcinogens include the helminthiases caused by Schistosoma haematobium and Opisthorchis viverrini. The molecular mediators underlying the infection with these parasites and cancer remain unclear. Although carcinogenesis is a multistep process, we have postulated that these parasites release metabolites including oxysterols and estrogen-like metabolites that interact with host cell DNA. How and why the parasite produce/excrete these metabolites remain unclear. A gene encoding a CYP enzyme was identified in schistosomes and opisthorchiids. Therefore, it is reasonable hypothesized that CYP 450 might play a role in generation of pro-inflammatory and potentially carcinogenic compounds produced by helminth parasites such as oxysterols and catechol estrogens. Here, we performed enzymatic assays using several isoforms of CYP 450 as CYP1A1, 2E1 and 3A4 which are involved in the metabolism of chemical carcinogens that have been associated with several cancer. The main aim was the analysis of the role of these enzymes in production of helminth-associated metabolites and DNA-adducts.

Method

The effect of cytochrome P450 enzymes CYP 1A1, 2E1 and 3A4 during the interaction between DNA, glycocholic acid and taurochenodeoxycholate sodium on the formation of DNA-adducts and metabolites associated with urogenital schistosomiasis (UGS) and opisthorchiasis was investigated in vitro. Liquid chromatography/mass spectrometry was used to detect and identify metabolites.

Main findings

Through the enzymatic assays we provide a deeper understanding of how metabolites derived from helminths are formed and the influence of CYP 450. The assays using compounds similar to those previously observed in helminths as glycocholic acid and taurochenodeoxycholate sodium, allowed the detection of metabolites in their oxidized form and their with DNA. Remarkably, these metabolites were previously associated with schistosomiaisis and opisthorchiasis. Thus, in the future, it may be possible to synthesize this type of metabolites through this methodology and use them in cell lines to clarify the carcinogenesis process associated with these diseases.

Principal conclusions

Metabolites similar to those detected in helminths are able to interact with DNA in vitro leading to the formation of DNA adducts. These evidences supported the previous postulate that imply helminth-like metabolites as initiators of helminthiases-associated carcinogenesis. Nonetheless, studies including these kinds of metabolites and cell lines in order to evaluate its potential carcinogenic are required.

Inhibition of the Formation In Vitro of Putatively Carcinogenic Metabolites Derived from S. haematobium and O. viverrini by Combination of Drugs with Antioxidants

Infections caused by Schistosoma haematobium and Opisthorchis viverrini are classified as carcinogenic. Although carcinogenesis might be a multifactorial process, it has been postulated that these helminth produce/excrete oxysterols and estrogen-like metabolites that might act as initiators of their infection-associated carcinogenesis. Current treatment and control of these infections rely on a single drug, praziquantel, that mainly targets the parasites and not the pathologies related to the infection including cancer. Thus, there is a need to search for novel therapeutic alternatives that might include combinations of drugs and drug repurposing. Based on these concepts, we propose a novel therapeutic strategy that combines drugs with molecule antioxidants. We evaluate the efficacy of a novel therapeutic strategy to prevent the formation of putative carcinogenic metabolites precursors and DNA adducts. Firstly, we used a methodology previously established to synthesize metabolites precursors and DNA adducts in the presence of CYP450. Then, we evaluated the inhibition of their formation induced by drugs and antioxidants alone or in combination. Drugs and resveratrol alone did not show a significant inhibitory effect while N-acetylcysteine inhibited the formation of most metabolite precursors and DNA adducts. Moreover, the combinations of classical drugs with antioxidants were more effective rather than compounds alone. This strategy might be a valuable tool to prevent the initiation of helminth infection-associated carcinogenesis.

Schistosomiasis and Infertility: What Do We Know?

There is increasing attention on the complex interactions occurring between schistosome parasites and their hosts. However, little is known about the occurrence, epidemiology, and mechanisms of schistosomiasis-associated infertility. In this article, we argue that an in-depth understanding of the interplay between parasites and the host endocrine system may significantly enhance current knowledge of infertility in infected individuals. We discuss the basic hormonal mechanisms that may lead to the discovery of entirely novel anthelmintic interventions against schistosomiasis.

High-quality Schistosoma haematobium genome achieved by single-molecule and long-range sequencing

BACKGROUND

Schistosoma haematobium causes urogenital schistosomiasis, a neglected tropical disease affecting >100 million people worldwide. Chronic infection with this parasitic trematode can lead to urogenital conditions including female genital schistosomiasis and bladder cancer. At the molecular level, little is known about this blood fluke and the pathogenesis of the disease that it causes. To support molecular studies of this carcinogenic worm, we reported a draft genome for S. haematobium in 2012. Although a useful resource, its utility has been somewhat limited by its fragmentation.

FINDINGS

Here, we systematically enhanced the draft genome of S. haematobium using a single-molecule and long-range DNA-sequencing approach. We achieved a major improvement in the accuracy and contiguity of the genome assembly, making it superior or comparable to assemblies for other schistosome species. We transferred curated gene models to this assembly and, using enhanced gene annotation pipelines, inferred a gene set with as many or more complete gene models as those of other well-studied schistosomes. Using conserved, single-copy orthologs, we assessed the phylogenetic position of S. haematobium in relation to other parasitic flatworms for which draft genomes were available.

CONCLUSIONS

We report a substantially enhanced genomic resource that represents a solid foundation for molecular research on S. haematobium and is poised to better underpin population and functional genomic investigations and to accelerate the search for new disease interventions.

Inflammation-associated pathologies in a case of prostate schistosomiasis: Implications for a causal role in prostate carcinogenesis

BACKGROUND

Urogenital infection with Schistosoma haematobium is a risk factor for the development of squamous cell carcinoma of the urinary bladder. The pathophysiology is thought to be mediated in part by inflammation, cellular damage, and bladder regeneration induced by the parasitic infection. Herein, we report an unusual case of schistosomiasis of the prostate that was found concurrent with prostate adenocarcinoma in a radical prostatectomy specimen from a man in the United States.

METHODS

The infecting Schistosoma species was characterized via histomorphology and acid-fast stain. The concurrent Gleason score 6 prostate cancer was assessed for ETS transcription factor ERG (ERG), phosphatase and tensin homolog (PTEN), p27, and p53 status using immunohistochemistry (IHC). Cellular proliferation and the presence of intermediate cells in prostatic atrophy were assessed via immunostaining for Ki67 and CK903, respectively.

RESULTS

Histomorphology and acid-fast stain of the infecting species were consistent with S. haematobium. We classified the Gleason score 6 prostate adenocarcinoma via IHC as ERG positive, PTEN intact, p27 intact, and without p53 nuclear accumulation. The prostatic epithelium immediately adjacent to the schistosomiasis-related granulomatous inflammation was atrophic and accompanied by increased cellular proliferation and the presence of intermediate cells. Upon literature review, we determined that prostate schistosomiasis is associated with a young age of prostate cancer diagnosis and highly aggressive prostate cancer.

CONCLUSIONS

This is a rare case of prostate schistosomiasis in the United States; however, prostate schistosomiasis occurs frequently in endemic areas. The patient had traveled to a Schistosoma-endemic region, which was the likely location of exposure to the parasite. To our knowledge, this is the first report of the association of proliferative inflammatory atrophy and intermediate cells with schistosomiasis of the prostate. We propose that prostate schistosomiasis may be considered as a risk factor for the development of prostate cancer in geographic regions where Schistosoma species are endemic.

Differential responses of epithelial cells from urinary and biliary tract to eggs of Schistosoma haematobium and S. mansoni

Chronic urogenital schistosomiasis can lead to squamous cell carcinoma of the bladder. The International Agency for Research on Cancer classifies the infection with S. haematobium as a group 1 carcinogen, a definitive cause of cancer. By contrast, hepatointestinal schistosomiasis due to the chronic infection with S. mansoni or S. japonicum associated with liver periportal fibrosis, does not apparently lead to malignancy. The effects of culturing human epithelial cells, HCV29, established from normal urothelium, and H69, established from cholangiocytes, in the presence of S. haematobium or S. mansoni eggs were investigated. Cell growth of cells co-cultured with schistosome eggs was monitored in real time, and gene expression analysis of oncogenesis, epithelial to mesenchymal transition and apoptosis pathways was undertaken. Schistosome eggs promoted proliferation of the urothelial cells but inhibited growth of cholangiocytes. In addition, the tumor suppressor P53 pathway was significantly downregulated when exposed to schistosome eggs, and downregulation of estrogen receptor was predicted in urothelial cells exposed only to S. haematobium eggs. Overall, cell proliferative responses were influenced by both the tissue origin of the epithelial cells and the schistosome species.

Imbalance of Steroid Hormones in Hamsters Infected with Schistosoma mansoni

OBJECTIVE

Schistosomiasis is a debilitating disease that affects 200 million people worldwide. Schistosoma haematobium and Schistosoma mansoni are the major causative agents of this disease. Cancer-association and infertility-association in Schistosoma haematobium infection have already been described and it is known that the parasite produces a catechol-estrogen molecule that induces a hormonal imbalance in the host.

METHODS

In order to better understand the relation of hormonal imbalance in experimental Schistosoma mansoni infection, we investigated a serum panel of steroid hormones in Schistosoma mansoni infected hamsters.

RESULTS

We found a decrease in the serum levels of Estradiol (E2), Testosterone and Progesterone in infected females and an increase of Testosterone and a decrease in Progesterone in infected males in comparison with controls.

CONCLUSION

These results indicate that S. mansoni alters the levels of steroid hormones in infected males and females and it will increase the repertoire of data about the host-parasite molecular interplay and its relation with the endocrine system.

Schistosoma Egg Antigen Induces Oncogenic Alterations in Human Prostate Cells

Schistosomiasis is a neglected tropical disease that affects 200 million people and accounts for 100,000 deaths annually. In endemic geographical areas, schistosomiasis has been implicated as an etiological agent in the pathogenesis of bladder, colorectal, and renal carcinoma largely due to Schistosoma eggs in tissues that comes with chronic infection. Several studies have also reported cases of association between Schistosoma infection and prostate cancer. The possible causal association is however poorly understood. We hypothesized in this study that infection of the prostate cells with Schistosoma spp promotes cancer. Urine samples from individuals living in Galilea, a schistosomiasis endemic community in the Ga South District of Ghana, were collected and screened for Schistosoma infection via microscopy and multiplex PCR. Soluble egg antigens (SEA) were prepared from Schistosoma egg-positive urine samples and assessed for the ability to induce cancer-like phenotypes including excessive proliferation, oxidative stress (reduced glutathione (GSH) depletion), and diminished apoptosis in cultured human prostate (PNT2) cells. Molecular analysis revealed infecting schistosome species to be S. haematobium and S. mansoni. Prostate cell proliferation was significantly induced by 12.5 μg/ml SEA (p = 0.029). Also, SEA dose-dependently depleted cellular GSH. Flow cytometric analysis and fluorescence staining revealed that SEA dose-dependently diminished apoptosis, significantly, in prostate cells. Findings of this study suggest that schistosome infection may play a role in the pathogenesis of prostate cancer. In vivo studies are however needed to confirm this association.

Understanding Urogenital Schistosomiasis-Related Bladder Cancer: An Update

Infection with Schistosoma haematobium leads to urogenital schistosomiasis, which has been correlated with the occurrence of bladder cancer. However, mechanisms responsible for this association have not yet been clearly identified. In this short review, we provide an update, highlighting the most recent studies on schistosome-associated bladder cancer, including those that focus on identifying changes in host biology during S. haematobium infection, as well as studies for the identification of potentially pro-carcinogenic parasite molecules, and we offer a discussion on some possible mechanisms driving schistosomal bladder cancer.

Fasciola Hepatica Extract Induces Cell Death of Mammalian Cells

Background

Fascioliasis is a neglected tropical disease that affects poor people from poor and developing countries. In the world, it has been estimated that at least 2.6 million people are affected with this disease. The International agency for Research on Cancer, states that O. viverrini and C. sinensis, also liver flukes, are considered as definitive causes of cholangiocarcinoma. However, fascioliasis caused by F. hepatica has not been associated with cancer to date. There are not any known causative associations between this parasite and liver cancer (cholangiocarcinoma).

Methods

Chine Hamster Ovary (CHO) cells were treated with F. hepatica extracts and cell proliferation was assessed by using the indirect method for estimating cell number based on the mitochondrial activity with MTS cell proliferation reagent. We observed unexpected death of these cells when treated with F. hepatica extracts.

Results

We now hypothesize that this parasite could be used as a medically-important trematode pathogen in cancer therapy.

An Epidemiological Trend of Urogenital Schistosomiasis in Ethiopia

Schistosomiasis is a major public health problem in Ethiopia. Currently, the prevalence of the disease can possibly be heightened due to man-made ecological transformations particularly related to the recent development programs involving irrigation and construction of dams. The expansion of some of the water resource development projects has been cited enhancing the upsurge of urogenital schistosomiasis mainly in the lower altitude areas of the country. In connection to the extensive initiation of development projects in low altitude areas of the country, simultaneous and adequate attentions have never been given to address a pre-assessment of health impacts of the development programs prior to launching the projects. Helpful appraisals focusing on evaluation of epidemiology of urogenital schistosomiasis in Ethiopia have not been explored. Therefore, the current review attempts to trace an overall picture of the epidemiological status of urogenital schistosomiasis in the country; the past and existing trends of urogenital schistosomiasis surveys and control programs of the country are reviewed. Essential recommendations are highlighted for possible inputs in future control design strategies of national control program of schistosomiasis.

Estrogen Metabolism-Associated CYP2D6 and IL6-174G/C Polymorphisms in Schistosoma haematobium Infection

Schistosoma haematobium is a human blood fluke causing a chronic infection called urogenital schistosomiasis. Squamous cell carcinoma of the urinary bladder (SCC) constitutes chronic sequelae of this infection, and S. haematobium infection is accounted as a risk factor for this type of cancer. This infection is considered a neglected tropical disease and is endemic in numerous countries in Africa and the Middle East. Schistosome eggs produce catechol-estrogens. These estrogenic molecules are metabolized to active quinones that induce modifications in DNA. The cytochrome P450 (CYP) enzymes are a superfamily of mono-oxygenases involved in estrogen biosynthesis and metabolism, the generation of DNA damaging procarcinogens, and the response to anti-estrogen therapies. IL6 Interleukin-6 (IL-6) is a pleiotropic cytokine expressed in various tissues. This cytokine is largely expressed in the female urogenital tract as well as reproductive organs. Very high or very low levels of IL-6 are associated with estrogen metabolism imbalance. In the present study, we investigated the polymorphic variants in the CYP2D6 gene and the C-174G promoter polymorphism of the IL-6 gene on S. haematobium-infected children patients from Guine Bissau. CYP2D6 inactivated alleles (28.5%) and IL6G-174C (13.3%) variants were frequent in S. haematobium-infected patients when compared to previously studied healthy populations (4.5% and 0.05%, respectively). Here we discuss our recent findings on these polymorphisms and whether they can be predictive markers of schistosome infection and/or represent potential biomarkers for urogenital schistosomiasis associated bladder cancer and infertility.

Infection with Opisthorchis felineus induces intraepithelial neoplasia of the biliary tract in a rodent model

The liver fluke Opisthorchis felineus is a member of the triad of epidemiologically relevant species of the trematode family Opisthorchiidae, and the causative agent of opisthorchiasis felinea over an extensive range that spans regions of Eurasia. The International Agency for Research on Cancer classifies the infection with the liver flukes Opisthorchis viverrini and Clonorchis sinensis as group 1 agents and a major risk factor for cholangiocarcinoma. However, the carcinogenic potential of the infection with O. felineus is less clear. Here, we present findings that support the inclusion of O. felineus in the Group 1 list of biological carcinogens. Two discrete lines of evidence support the notion that infection with this liver fluke is carcinogenic. First, novel oxysterol-like metabolites detected by liquid chromatography-mass spectroscopy in the egg and adult developmental stages of O. felineus, and in bile, sera, and urine of liver fluke-infected hamsters exhibited marked similarity to oxysterol-like molecules known from O. viverrini. Numerous oxysterols and related DNA-adducts detected in the liver fluke eggs and in bile from infected hamsters suggested that infection-associated oxysterols induced chromosomal lesions in host cells. Second, histological analysis of liver sections from hamsters infected with O. felineus confirmed portal area enlargement, inflammation with severe periductal fibrosis and changes in the epithelium of the biliary tract characterized as biliary intraepithelial neoplasia, BilIN. The consonance of these biochemical and histopathological changes revealed that O. felineus infection in this rodent model induced precancerous lesions conducive to malignancy.

Halting Schistosoma haematobium - associated bladder cancer

Background

At present schistosomiasis is endemic in 78 countries affecting more than 260 million people. Schistosomiasis haematobia alone affects more than 112 millions.

Material and Methods

We performed a computerized search of Pubmed database with keywords: bladder cancer cost and schistosomiasis mass treatment.

Results

Bladder cancer is an important sequelae of this infection. In low-resource countries, where this disease is endemic, individuals inflicted with bladder cancer have very limited access to treatment and death is most probably certain.

Conclusion

Mass treatment with praziquantel is an easy, safe and inexpensive treatment that could save the lives of thousands and reduce the morbidity of millions.

Angiogenesis in Schistosoma haematobium-associated urinary bladder cancer

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.

The microbiome in urogenital schistosomiasis and induced bladder pathologies

Background

Human schistosomiasis is a highly prevalent neglected tropical disease (NTD) caused by Schistosoma species. Research on the molecular mechanisms influencing the outcomes of bladder infection by Schistosoma haematobium is urgently needed to develop new diagnostics, therapeutics and infection prevention strategies. The objective of the research study was to determine the microbiome features and changes in urine during urogenital schistosomiasis and induced bladder pathologies.

Methodology

Seventy participants from Eggua, southwestern Nigeria provided morning urine samples and were screened for urogenital schistosomiasis infection and bladder pathologies in a cross-sectional study. Highthroughput NGS sequencing was carried out, targeting the 16S V3 region. Filtered reads were processed and analyzed in a bioinformatics pipeline.

Principal findings

The study participants (36 males and 34 females, between ages 15 and 65) were categorized into four groups according to status of schistosomiasis infection and bladder pathology. Data analytics of the next-generation sequencing reads revealed that Proteobacteria and Firmicutes dominated and had influence on microbiome structure of both non-infected persons and persons with urogenital schistosomiasis. Furthermore, gender and age influenced taxa abundance independent of infection or bladder pathology. Several taxa distinguished urogenital schistosomiasis induced bladder pathologies from urogenital schistosomiasis infection alone and from healthy persons, including known immune-stimulatory taxa such as Fusobacterium, Sphingobacterium and Enterococcus. Some of these significant taxa, especially Sphingobacterium were projected as markers of infection, while several genera including potentially beneficial taxa such as Trabulsiella and Weissella, were markers of the non-infected. Finally, expected changes in protein functional categories were observed to relate to cellular maintenance and lipid metabolism.

Conclusion

The urinary microbiome is a factor to be considered in developing biomarkers, diagnostic tools, and new treatment for urogenital schistosomiasis and induced bladder pathologies.

The human microbiome comprises bacteria (plus viruses, fungi and archeae) inhabiting different sites of the body. They do not specifically cause diseases, but their presence, absence or population influence body functions. We therefore examined such organisms found along the urinary tract, in persons living in a rural community in Nigeria who considered themselves healthy, were infected with the parasite Schistosoma haematobium or had developed bladder complications along with the parasite infection. We found that these groups shared a large portion of the microbiome, but there were microbial species unique to infected persons and those with bladder complication. Some of these were capable of inducing inflammation and could offer less protection to the host. We also predicted pathways that are affected by the difference in the microbiome.

The role of estradiol metabolism in urogenital schistosomiasis-induced bladder cancer

Urogenital schistosomiasis is a neglected tropical disease that can lead to bladder cancer. How urogenital schistosomiasis induces carcinogenesis remains unclear, although there is evidence that the human blood fluke Schistosoma haematobium, the infectious agent of urogenital schistosomiasis, releases estradiol-like metabolites. These kind of compounds have been implicated in other cancers. Aiming for enhanced understanding of the pathogenesis of the urogenital schistosomiasis-induced bladder cancer, here we review, interpret, and discuss findings of estradiol-like metabolites detected in both the parasite and in the human urine during urogenital schistosomiasis. Moreover, we predict pathways and enzymes that are involved in the production of these metabolites emphasizing their potential effects on the dysregulation of the tumor suppressor gene p53 expression during urogenital schistosomiasis. Enhanced understanding of these potential carcinogens may not only shed light on urogenital schistosomiasis-induced neoplasia of the bladder, but would also facilitate development of interventions and biomarkers for this and other infection-associated cancers at large.

Estrogen catechols detection as biomarkers in schistosomiasis induced cancer and infertility

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.

Trihalomethanes in liver pathology: Mitochondrial dysfunction and oxidative stress in the mouse

Trihalomethanes (THMs) are disinfection byproducts found in chlorinated water, and are associated with several different kinds of cancer in human populations and experimental animal models. Metabolism of THMs proceeds through enzymes such as GSTT1 and CYP2E1 and gives rise to reactive intermediates, which form the basis for their toxic activities. The aim of this study was to assess the mitochondrial dysfunction caused by THMs at low levels, and the resulting hepatic histological and biochemical changes in the mouse. Male ICR mice were administered with two THMs: dibromochloromethane (DBCM) and bromodichloromethane (BDCM); once daily, by gavage, to a total of four administrations. Animals were sacrificed four weeks after DBCM and BDCM administrations. Blood biochemistry was performed for alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), total bilirubin (TB), albumin (Alb), total protein (TP), creatinine, and urea. Animals exposed to DBCM and BDCM showed elevated ALT and TB levels (p < 0.05) as compared with controls. Histological analysis confirmed the presence of vacuolar degenerescence and a multifocal necrotizing hepatitis in 33% of animals (n = 2). Mitochondrial analysis showed that THMs reduced mitochondrial bioenergetic activity (succinate dehydrogenase (SQR), cytochrome c oxidase (COX), and ATP synthase) and increased oxidative stress (glutathione S-transferase (GST)) in hepatic tissues (p < 0.05). These results add detail to the current understanding of the mechanisms underlying THM-induced toxicity, supporting the role of mitochondrial dysfunction and oxidative stress in liver toxicity caused by DBCM and BDCM. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1009-1016, 2016.

Schistosoma haematobium in Guinea-Bissau: unacknowledged morbidity due to a particularly neglected parasite in a particularly neglected country

Schistosomiasis is the major neglected tropical helminthic disease worldwide. Current knowledge on the epidemiology of schistosomiasis in Guinea-Bissau is scarce and regarding to the absence of Schistosoma haematobium (S.h.). Therefore, a pilot study was undertaken to assess the prevalence and morbidity due to S.h. infection in randomly selected 90 children and adolescents aged 6 to 15 years. Prevalence of S.h. infection was 20.00 % (18/90). Microhematuria was observed in 61.11 % (11/18) of S.h.-egg-excreting vs. 37.50 % (27/72) of non-S.h.-egg-excreting children p ≤ 0.01. Body mass index (BMI) was less than 15 kg/m(2) in 52/90 (57.78 %) of all children and adolescents, but this proportion increased to 66.67 % (12/18) in S.h.-infected children who were more frequently stunted and wasted than in non-infected children. The mean weight-for-age Z score (WAZ) was reduced in S.h. infected as compared to non-infected children (-1.48 ± 1.08 SD vs. -0.80 ± 1.11 SD; p ≤ 0.01). To our knowledge, this is the first epidemiologic report on S. haematobium infection in Guinea-Bissau since 22 years. Even in this relatively small study sample, it appears that S. haematobium, besides the well-known symptoms such as hematuria, leads to significant, albeit commonly unacknowledged morbidity such as stunting and wasting. These observations underscore the notion that this vulnerable but neglected population urgently needs to be targeted for implementation of measures for treatment and control.

Why does infection with some helminths cause cancer?

Infections with Opisthorchis viverrini, Clonorchis sinensis and Schistosoma haematobium are classified as Group 1 biological carcinogens: definitive causes of cancer. These worms are metazoan eukaryotes, unlike the other Group 1 carcinogens including human papilloma virus, hepatitis C virus, and Helicobacter pylori. By contrast, infections with phylogenetic relatives of these helminths, also trematodes of the phylum Platyhelminthes and major human pathogens, are not carcinogenic. These inconsistencies prompt several questions, including how might these infections cause cancer? And why is infection with only a few helminth species carcinogenic? Here we present an interpretation of mechanisms contributing to the carcinogenicity of these helminth infections, including roles for catechol estrogen- and oxysterol-metabolites of parasite origin as initiators of carcinogenesis.

Urine biomarkers of schistosomiais and its associated bladder cancer

Schistosomiasis (SCH) is the second only to malaria among the parasitic diseases affecting humans regarding the prevalence of infection worldwide. In this nonsystematic review, we summarize the existing data on commercially available and promising investigational urine markers for the detection of SCH and its associated bladder cancer (BC). We searched PubMed, Scopus and Cochran without time limits. We reviewed the recent literatures on urine-based markers for SCH and its associated BC. Many studies identified several urine biomarkers of Schistosoma haematobium and Schistosoma mansoni worms and their associated BC using automated, inexpensive, quantitative assays in urine. These markers may aid in early detection of bladder carcinoma and have the potential to reduce the number of follow-up cystoscopy, thus reducing healthcare costs and patient discomfort, at the same time. Nevertheless, clinical evidence is insufficient to warrant the substitution of the cystoscopic follow-up scheme by any of the currently available urine marker tests.

The role of estrogens and estrogen receptor signaling pathways in cancer and infertility: the case of schistosomes

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. Schistosomiasis haematobia also appears to negatively influence fertility, and is particularly associated with female infertility. Given that estrogens and estrogen receptors are key players in human reproduction, we speculate that schistosome estrogen-like molecules may contribute to infertility through hormonal imbalances. Here, we review recent findings on the role of estrogens and estrogen receptors on both carcinogenesis and infertility associated with urogenital schistosomiasis and discuss the basic hormonal mechanisms that might be common in cancer and infertility.

Estrogen-like metabolites and DNA-adducts in urogenital schistosomiasis-associated bladder cancer

An estrogen-DNA adduct mediated pathway may be involved in the pathogenesis of the squamous cell carcinoma of the bladder associated with infection with the blood fluke Schistosoma haematobium. Extracts from developmental stages of S. haematobium, including eggs, induce tumor-like phenotypes in cultured cells. In addition, estrogen-derived, reactive metabolites occur in this pathogen and in sera of infected persons. Liquid chromatography-mass spectrometry analysis was performed on urine from 40 Angolans diagnosed with urogenital schistosomiasis (UGS), half of who also presented UGS-associated squamous cell carcinoma and/or urothelial cell carcinoma. The analysis revealed numerous estrogen-like metabolites, including seven specifically identified in UGS cases, but not reported in the database of metabolites in urine of healthy humans. These schistosome infection-associated metabolites included catechol estrogen quinones (CEQ) and CEQ-DNA-adducts, two of which had been identified previously in S. haematobium. In addition, novel metabolites derived directly from 8-oxo-7, 8-dihydro-2'-deoxyguanosine (8-oxodG) were identified in urine of all 40 cases of UGS. These metabolites can be expected to provide deeper insights into the carcinogenesis UGS-induced bladder cancer, and as biomarkers for diagnosis and/or prognosis of this neglected tropical disease-linked cancer.

Bladder cancer and urinary Schistosomiasis in Angola

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.

Schistosome and liver fluke derived catechol-estrogens and helminth associated cancers

Infection with helminth parasites remains a persistent public health problem in developing countries. Three of these pathogens, the liver flukes Clonorchis sinensis, Opisthorchis viverrini and the blood fluke Schistosoma haematobium, are of particular concern due to their classification as Group 1 carcinogens: infection with these worms is carcinogenic. Using liquid chromatography-mass spectrometry (LC-MS/MS) approaches, we identified steroid hormone like (e.g., oxysterol-like, catechol estrogen quinone-like, etc.) metabolites and related DNA-adducts, apparently of parasite origin, in developmental stages including eggs of S. haematobium, in urine of people with urogenital schistosomiasis, and in the adult stage of O. viverrini. Since these kinds of sterol derivatives are metabolized to active quinones that can modify DNA, which in other contexts can lead to breast and other cancers, helminth parasite associated sterols might induce tumor-like phenotypes in the target cells susceptible to helminth parasite associated cancers, i.e., urothelial cells of the bladder in the case of urogenital schistosomiasis and the bile duct epithelia or cholangiocytes, in the case of O. viverrini and C. sinensis. Indeed we postulate that helminth induced cancers originate from parasite estrogen-host epithelial/urothelial cell chromosomal DNA adducts, and here we review recent findings that support this conjecture.

Controversies and challenges in research on urogenital schistosomiasis-associated bladder cancer

Urogenital schistosomiasis, infection with Schistosoma haematobium, is linked to increased risk for the development of bladder cancer, but the importance of various mechanisms responsible for this association remains unclear, in part, owing to lack of sufficient and appropriate animal models. New advances in the study of this parasite, bladder regenerative processes, and human schistosomal bladder cancers may shed new light on the complex biological processes that connect S. haematobium infection to bladder carcinogenesis.

Urinary estrogen metabolites and self-reported infertility in women infected with Schistosoma haematobium

BACKGROUND

Schistosomiasis is a neglected tropical disease, endemic in 76 countries, that afflicts more than 240 million people. The impact of schistosomiasis on infertility may be underestimated according to recent literature. Extracts of Schistosoma haematobium include estrogen-like metabolites termed catechol-estrogens that down regulate estrogen receptors alpha and beta in estrogen responsive cells. In addition, schistosome derived catechol-estrogens induce genotoxicity that result in estrogen-DNA adducts. These catechol estrogens and the catechol-estrogen-DNA adducts can be isolated from sera of people infected with S. haematobium. The aim of this study was to study infertility in females infected with S. haematobium and its association with the presence of schistosome-derived catechol-estrogens.

METHODOLOGY/PRINCIPAL FINDINGS

A cross-sectional study was undertaken of female residents of a region in Bengo province, Angola, endemic for schistosomiasis haematobia. Ninety-three women and girls, aged from two (parents interviewed) to 94 years were interviewed on present and previous urinary, urogenital and gynecological symptoms and complaints. Urine was collected from the participants for egg-based parasitological assessment of schistosome infection, and for liquid chromatography diode array detection electron spray ionization mass spectrometry (LC/UV-DAD/ESI-MSn) to investigate estrogen metabolites in the urine. Novel estrogen-like metabolites, potentially of schistosome origin, were detected in the urine of participants who were positive for eggs of S. haematobium, but not detected in urines negative for S. haematobium eggs. The catechol-estrogens/ DNA adducts were significantly associated with schistosomiasis (OR 3.35; 95% CI 2.32-4.84; P≤0.001). In addition, presence of these metabolites was positively associated with infertility (OR 4.33; 95% CI 1.13-16.70; P≤0.05).

CONCLUSIONS/SIGNIFICANCE

Estrogen metabolites occur widely in diverse metabolic pathways. In view of the statistically significant association between catechol-estrogens/ DNA adducts and self-reported infertility, we propose that an estrogen-DNA adduct mediated pathway in S. haematobium-induced ovarian hormonal deregulation could be involved. In addition, the catechol-estrogens/ DNA adducts described here represent potential biomarkers for schistosomiasis haematobia.