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Liver fluke infection caused by Opisthorchis viverrini is a major public health problem in Thailand and adjacent countries. In addition to infection-associated morbidity, infection with O. viverrini and the related Clonorchis sinensis are unarguable risk factors for cholangiocarcinoma (CAA, bile-duct cancer). Here we review the pathogenesis of opisthorchiasis and the association between O. viverrini infection and bile-duct cancer, focusing on the molecular parallels between wound healing, chronic inflammation, and cancer development. We review a schema for human disease progression from fluke infection, chronic opisthorchiasis, advanced periductal fibrosis, and cholangiocarcinogenesis, and present a rationale for biomarker discovery to facilitate early intervention. We conclude by addressing post-genomic advances with a view to developing new control strategies to combat this infectious cancer. [Copyright &y& Elsevier]

Because tropical medicine and parasitology research has moved into the postgenomic era, an enormous amount of gene sequence information for parasitic helminths is now accumulating. These sequences undoubtedly hold information that can be used for new interventions and control. However, to exploit the new resource, methods for gene manipulation and transformation of parasitic worms are needed. Until recently, gene manipulation approaches had not been seriously addressed. This situation is now changing in response to the availability of genome sequences and other advances. In this article, we review advances in the transgenesis and gene silencing of parasitic worms. [Copyright &y& Elsevier]

Twenty years ago, an article by Carter and Colley was published in an early issue of this journal. The report outlined pioneering studies by several laboratories into schistosome molecular biology and molecular genetics. To commemorate that prescient report and, in like fashion, to provide a brief (and non-comprehensive) synopsis of progress in this field up to the present time, I will outline some key aspects of the molecular biology of schistosomes that have been reported in the intervening years. [Copyright &y& Elsevier]

Blood-feeding parasites employ a battery of proteolytic enzymes to digest the contents of their bloodmeal. Host haemoglobin is a major substrate for these proteases and, therefore, a driving force in the evolution of parasite-derived proteolytic enzymes. This review will focus on the digestive proteases of the major blood-feeding nematodes – hookworms (Ancylostoma spp. and Necator americanus) and the ruminant parasite, Haemonchus contortus – but also compares and contrasts these proteases with recent findings from schistosomes and malaria parasites. Haematophagous nematodes express proteases of different mechanistic classes in their intestines, many of which have proven or putative roles in degradation of haemoglobin and other proteins involved in nutrition. Moreover, the fine specificity of the relationships between digestive proteases and their substrate proteins provides a new molecular paradigm for understanding host–parasite co-evolution. Numerous laboratories are actively investigating these molecules as antiparasite vaccine targets. [Copyright &y& Elsevier]

A substantial fraction of the genome of most eukaryotes, including those of metazoan parasites, is predicted to comprise repetitive sequences. Mobile genetic elements (MGEs) will make up much of these repetitive sequences, particularly the interspersed sequences. This article reviews information on MGEs that have colonized the genomes of metazoan parasites (i.e. parasites of parasites). Helminth and mosquito genomes, in particular, are compared with those of better-understood model organisms. MGEs from the genomes of metazoan parasites can be expected to have practical uses in transgenesis and epidemiological studies. [Copyright &y& Elsevier]

We live in the era of post-genomics, a term that was, until recently, inappropriate when considering the blood flukes of humans because of the relative lack of knowledge of the schistosome genome. The position has, however, changed dramatically following the recent publication of two landmark papers on transcriptome analysis of Schistosoma japonicum and Schistosoma mansoni. In a quantum leap, both studies report on the identification of many novel genes and genes not previously known from schistosomes. The datasets provide new insights into the biology of the schistosomes and offer an opportunity for identification of potential antischistosome vaccine candidates and drug targets. Remarkable recent progress has also been achieved in genomic sequencing, and completed genomes for both species can be expected shortly. [Copyright &y& Elsevier]

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. [ABSTRACT FROM AUTHOR]

Highlights: [•] Flukes and cestodes do not have a piRNA pathway. [•] How might these flatworm pathogens defend the germline genome? [•] Fluke genomes are replete with mobile genetic elements. [ABSTRACT FROM AUTHOR]