Knockout of liver fluke granulin, Ov-grn-1, impedes malignant transformation during chronic infection with Opisthorchis viverrini

Transcriptome changes of liver fluke Opisthorchis viverrini in diabetic hamsters

A recent study in hamsters showed that infection with the liver fluke Opisthorchis viverrini in diabetic hosts worsens the severity of hepatobiliary disease. However, the effects of diabetes on the worm's phenotype and gene expression pattern remain unknown. This study investigated the impact of diabetes on the global gene expression and development of O. viverrini in diabetic hamsters. Parasitological parameters were assessed, and mRNA sequencing with bioinformatic analysis was performed. The study revealed that worm establishment rates in diabetic hamsters were directly correlated with fasting plasma glucose levels. Interestingly, worms collected from diabetic hosts exhibited stunted growth and reduced egg production. Transcriptomic analysis revealed significant alterations in gene expression, with 4314 and 567 differentially expressed genes at 21- and 35-days post-infection, respectively. Gene ontology enrichment analysis highlighted changes in biological processes related to stress response, metabolism, and cellular organization. Notably, genes associated with parasite virulence, including granulin, tetraspanins, and thioredoxins, showed significant upregulation in diabetic hosts. These findings demonstrate the profound impact of host diabetic status on O. viverrini development and gene expression, providing insights into the complex interplay between host metabolism and parasite biology, including molecular adaptations of O. viverrini in hosts. This study contributes to our understanding of opisthorchiasis in the context of metabolic disorders and may inform future strategies for disease management in diabetic human populations.

Animal granulins: In the GRN scheme of things

Granulins are conserved in nearly all metazoans, with an intriguing loss in insects. These pleiotropic peptides are involved in numerous physiological and pathological processes yet have been overwhelmingly examined in mammalian systems. While work in other animal models has been informative, a richer understanding of the proteins should be obtained by integrating knowledge from all available contexts. The main bodies of work described here include 1) the structure-function relationships of progranulin and its cleavage products, 2) the role of expanded granulin gene families and different isoforms in fish immunology, 3) the release of granulin peptides to promote host angiogenesis by parasitic worms, 4) a diversity of molluscan uses for granulins, including immune activation in intermediate hosts to trematodes, 5) knowledge gained on lysosomal functions from C. elegans and the stress-related activities of granulins. We provide an overview of functional reports across the Metazoa to inform much-needed future research.

Current State of Knowledge on Blood and Tissue-Based Biomarkers for Opisthorchis viverrini-induced Cholangiocarcinoma: A Review of Prognostic, Predictive, and Diagnostic Markers

Cholangiocarcinoma (CCA) is a prevalent cancer in Southeast Asia, with Opisthorchis viverrini (O.viverrini) infection being the primary risk factor. Most CCA cases in this region are diagnosed at advanced stages, leading to unfavorable prognoses. The development of stage-specific biomarkers for Opisthorchis viverrini-induced cholangiocarcinoma (Ov-CCA) holds crucial significance, as it facilitates early detection and timely administration of curative interventions, effectively mitigating the high morbidity and mortality rates associated with this disease in the Great Mekong region. Biomarkers are a promising approach for early detection, prognosis, and targeted treatment of CCA. Disease-specific biomarkers facilitate early detection and enable monitoring of therapy effectiveness, allowing for any necessary corrections. This review provides an overview of the potential O. viverrini-specific molecular biomarkers and important markers for diagnosing and monitoring Ov-CCA, discussing their prognostic, predictive, and diagnostic value. Despite the limited research in this domain, several potential biomarkers have been identified, encompassing both worm-induced and host-induced factors. This review offers a thorough examination of historical and contemporary progress in identifying biomarkers through multiomics techniques, along with their potential implications for early detection and treatment.

Getting off tract: contributions of intraorgan microbiota to cancer in extraintestinal organs

The gastrointestinal ecosystem has received the most attention when examining the contributions of the human microbiome to health and disease. This concentration of effort is logical due to the overwhelming abundance of microbes in the gut coupled with the relative ease of sampling compared with other organs. However, the intestines are intimately connected to multiple extraintestinal organs, providing an opportunity for homeostatic microbial colonisation and pathogenesis in organs traditionally thought to be sterile or only transiently harbouring microbiota. These habitats are challenging to sample, and their low microbial biomass among large amounts of host tissue can make study challenging. Nevertheless, recent findings have shown that many extraintestinal organs that are intimately linked to the gut harbour stable microbiomes, which are colonised from the gut in selective manners and have highlighted not just the influence of the bacteriome but that of the mycobiome and virome on oncogenesis and health.

Inflammatory cell responses in biliary mucosa during Opisthorchis viverrini infection: Insights into susceptibility differences among hosts

Background

Individual host susceptibility is believed to be a risk factor in the interaction between the host and the parasite. Since studying time series in humans is limited, animal models are replaced.

Aim

This study aims to explore and compare the pattern of inflammatory cell types along the biliary tract and their association with proliferative lesions in the early development of cholangiocarcinoma from susceptible and nonsusceptible animal models.

Methods

Thirty male Syrian golden hamsters and 30 BALB/c mice, serving as the susceptible and nonsusceptible animal models, were used in this comparative study. The animals were infected with 50 Opisthorchis viverrini metacercariae via gastric intubation. At days 1, 2, 7, 14, 28, and 56 postinfection (p.i.), five animals were randomly selected from each group and humanely sacrificed. The hepatobiliary tissues were collected and processed for histopathological study. Histochemical and immunohistochemical staining were applied to differentiate the inflammatory cell types. Kruskal-Wallis and Mann-Whitney tests were applied to assess all semi-quantitative and quantitative variables. The correlation between each variable was also analyzed using Spearman rank at a p-value < 0.05.

Results

The results demonstrated that mice had different patterns of infiltrating cell types when compared to hamsters. This suggested that the cellular response to the infection in mice occurred earlier than that in hamsters. The response in mice reached its peak at D7 to D14 and then rapidly declined at D28. In contrast, although the inflammatory response in hamsters started slowly, the response reached the peak at D28 and maintained a high level until D56. Significant differences in the number of inflammatory cells between mice and hamsters were seen at D1 (p = 0.047), D7 (p = 0.049), D28 (p = 0.040), and D56 (p < 0.040).

Conclusion

The inflammatory responses to O. viverrini infection in the nonsusceptible animal model occurred and declined earlier while the response in the susceptible animal model occurred later in a gradual manner. Both rodents are suitable animal models for the studies of opisthorchiasis susceptibility.

Cancerogenic parasites in veterinary medicine: a narrative literature review

Parasite infection is one of the many environmental factors that can significantly contribute to carcinogenesis and is already known to be associated with a variety of malignancies in both human and veterinary medicine. However, the actual number of cancerogenic parasites and their relationship to tumor development is far from being fully understood, especially in veterinary medicine. Thus, the aim of this review is to investigate parasite-related cancers in domestic and wild animals and their burden in veterinary oncology. Spontaneous neoplasia with ascertained or putative parasite etiology in domestic and wild animals will be reviewed, and the multifarious mechanisms of protozoan and metazoan cancer induction will be discussed.

Small extracellular vesicles but not microvesicles from Opisthorchis viverrini promote cell proliferation in human cholangiocytes

Chronic infection with O. viverrini has been linked to the development of cholangiocarcinoma (CCA), which is a major public health burden in the Lower Mekong River Basin countries, including Thailand, Lao PDR, Vietnam and Cambodia. Despite its importance, the exact mechanisms by which O. viverrini promotes CCA are largely unknown. In this study, we characterized different extracellular vesicle populations released by O. viverrini (OvEVs) using proteomic and transcriptomic analyses and investigated their potential role in host-parasite interactions. While 120k OvEVs promoted cell proliferation in H69 cells at different concentrations, 15k OvEVs did not produce any effect compared to controls. The proteomic analysis of both populations showed differences in their composition that could contribute to this differential effect. Furthermore, the miRNAs present in 120k EVs were analysed and their potential interactions with human host genes was explored by computational target prediction. Different pathways involved in inflammation, immune response and apoptosis were identified as potentially targeted by the miRNAs present in this population of EVs. This is the first study showing specific roles for different EV populations in the pathogenesis of a parasitic helminth, and more importantly, an important advance towards deciphering the mechanisms used in establishment of opisthorchiasis and liver fluke infection-associated malignancy.

Peptide derived from progranulin of the carcinogenic liver fluke, Opisthorchis viverrini stimulates cell hyperproliferation and proinflammatory cytokine production

Purpose

Progranulin (PGRN) is a secreted glycoprotein growth factor with roles in wound healing, inflammation, angiogenesis and malignancy. An orthologue of the gene encoding human PGRN was identified in the carcinogenic liver fluke Opisthorchis viverrini.

Methods

Sequence structure, general characteristics and possible function of O. viverrini PGRN was analyzed using bioinformatics. Expression profiles were investigated with quantitative RT-PCR, western blot and immunolocalization. A specific peptide of Ov-PGRN was used to investigate a role for this molecule in pathogenesis.

Results

The structure of the gene coding for O. viverrini PGRN was 36,463 bp in length, and comprised of 13 exons, 12 introns, and a promoter sequence. The Ov-pgrn mRNA is 2,768 bp in length and encodes an 846 amino acids with a predicted molecular mass of 91.61 kDa. Ov-PGRN exhibited one half and seven complete granulin domains. Phylogenetic analysis revealed that Ov-PGRN formed its closest relationship with PGRN of liver flukes in the Opisthorchiidae. Transcripts of Ov-pgrn were detected in several developmental stages, with highest expression in the metacercaria, indicating that Ov-PGRN may participate as a growth factor in the early development of O. viverrini. Western blot analysis revealed the presence of detected Ov-PGRN in both soluble somatic or excretory/secretory products, and immunolocalization indicated high levels of expression in the tegument and parenchyma of the adult fluke. Co-culture of a human cholangiocyte cell line and a peptide fragment of Ov-PGRN stimulated proliferation of cholangiocytes and upregulation of expression of the cytokines IL6 and IL8.

Conclusion

Ov-PGRN is expressed throughout the life cycle of liver fluke, and likely plays a key role in development and growth.