33 research outputs found
A Granulin-Like Growth Factor Secreted by the Carcinogenic Liver Fluke, Opisthorchis viverrini, Promotes Proliferation of Host Cells
The human liver fluke, Opisthorchis viverrini, infects millions of people throughout south-east Asia and is a major cause of cholangiocarcinoma, or cancer of the bile ducts. The mechanisms by which chronic infection with O. viverrini results in cholangiocarcinogenesis are multi-factorial, but one such mechanism is the secretion of parasite proteins with mitogenic properties into the bile ducts, driving cell proliferation and creating a tumorigenic environment. Using a proteomic approach, we identified a homologue of human granulin, a potent growth factor involved in cell proliferation and wound healing, in the excretory/secretory (ES) products of the parasite. O. viverrini granulin, termed Ov-GRN-1, was expressed in most parasite tissues, particularly the gut and tegument. Furthermore, Ov-GRN-1 was detected in situ on the surface of biliary epithelial cells of hamsters experimentally infected with O. viverrini. Recombinant Ov-GRN-1 was expressed in E. coli and refolded from inclusion bodies. Refolded protein stimulated proliferation of murine fibroblasts at nanomolar concentrations, and proliferation was inhibited by the MAPK kinase inhibitor, U0126. Antibodies raised to recombinant Ov-GRN-1 inhibited the ability of O. viverrini ES products to induce proliferation of murine fibroblasts and a human cholangiocarcinoma cell line in vitro, indicating that Ov-GRN-1 is the major growth factor present in O. viverrini ES products. This is the first report of a secreted growth factor from a parasitic worm that induces proliferation of host cells, and supports a role for this fluke protein in establishment of a tumorigenic environment that may ultimately manifest as cholangiocarcinoma
Deficiency in trefoil factor 1 (TFF1) increases tumorigenicity of human breast cancer cells and mammary tumor development in TFF1-knockout mice
Although trefoil factor 1 (TFF1; previously named pS2) is abnormally expressed in about 50% of human breast tumors, its physiopathological role in this disease has been poorly studied. Moreover, controversial data have been reported. TFF1 function in the mammary gland therefore needs to be clarified. In this study, using retroviral vectors, we performed TFF1 gain- or loss-of-function experiments in four human mammary epithelial cell lines: normal immortalized TFF1-negative MCF10A, malignant TFF1-negative MDA-MB-231 and malignant TFF1-positive MCF7 and ZR75.1. The expression of TFF1 stimulated the migration and invasion in the four cell lines. Forced TFF1 expression in MCF10A, MDA-MB-231 and MCF7 cells did not modify anchorage-dependent or -independent cell proliferation. By contrast, TFF1 knockdown in MCF7 enhanced soft-agar colony formation. This increased oncogenic potential of MCF7 cells in the absence of TFF1 was confirmed in vivo in nude mice. Moreover, chemically induced tumorigenesis in TFF1-deficient (TFF1-KO) mice led to higher tumor incidence in the mammary gland and larger tumor size compared with wild-type mice. Similarly, tumor development was increased in the TFF1-KO ovary and lung. Collectively, our results clearly show that TFF1 does not exhibit oncogenic properties, but rather reduces tumor development. This beneficial function of TFF1 is in agreement with many clinical studies reporting a better outcome for patients with TFF1-positive breast primary tumors
A Research Agenda for Helminth Diseases of Humans: Basic Research and Enabling Technologies to Support Control and Elimination of Helminthiases
Successful and sustainable intervention against human helminthiases depends on optimal utilisation of available control measures and development of new tools and strategies, as well as an understanding of the evolutionary implications of prolonged intervention on parasite populations and those of their hosts and vectors. This will depend largely on updated knowledge of relevant and fundamental parasite biology. There is a need, therefore, to exploit and apply new knowledge and techniques in order to make significant and novel gains in combating helminthiases and supporting the sustainability of current and successful mass drug administration (MDA) programmes. Among the fields of basic research that are likely to yield improved control tools, the Disease Reference Group on Helminth Infections (DRG4) has identified four broad areas that stand out as central to the development of the next generation of helminth control measures: 1) parasite genetics, genomics, and functional genomics; 2) parasite immunology; 3) (vertebrate) host–parasite interactions and immunopathology; and 4) (invertebrate) host–parasite interactions and transmission biology. The DRG4 was established in 2009 by the Special Programme for Research and Training in Tropical Diseases (TDR). The Group was given the mandate to undertake a comprehensive review of recent advances in helminthiases research in order to identify notable gaps and highlight priority areas. This paper summarises recent advances and discusses challenges in the investigation of the fundamental biology of those helminth parasites under the DRG4 Group's remit according to the identified priorities, and presents a research and development agenda for basic parasite research and enabling technologies that will help support control and elimination efforts against human helminthiases
Unlocking the Transcriptomes of Two Carcinogenic Parasites, Clonorchis sinensis and Opisthorchis viverrini
The two parasitic trematodes, Clonorchis sinensis and Opisthorchis viverrini, have a major impact on the health of tens of millions of humans throughout Asia. The greatest impact is through the malignant cancer ( = cholangiocarcinoma) that these parasites induce in chronically infected people. Therefore, both C. sinensis and O. viverrini have been classified by the World Health Organization (WHO) as Group 1 carcinogens. Despite their impact, little is known about these parasites and their interplay with the host at the molecular level. Recent advances in genomics and bioinformatics provide unique opportunities to gain improved insights into the biology of parasites as well as their relationships with their hosts at the molecular level. The present study elucidates the transcriptomes of C. sinensis and O. viverrini using a platform based on next-generation (high throughput) sequencing and advanced in silico analyses. From 500,000 sequences, >50,000 sequences were assembled for each species and categorized as biologically relevant based on homology searches, gene ontology and/or pathway mapping. The results of the present study could assist in defining molecules that are essential for the development, reproduction and survival of liver flukes and/or that are linked to the development of cholangiocarcinoma. This study also lays a foundation for future genomic and proteomic research of C. sinensis and O. viverrini and the cancers that they are known to induce, as well as novel intervention strategies
Relationship between microvessel count and postoperative survival in patients with intrahepatic cholangiocarcinoma.
BACKGROUND: The present study aimed to elucidate the relationship between microvessel count (MVC) according to CD34 expression and prognosis in intrahepatic cholangiocarcinoma (ICC) patients who underwent hepatectomy based on our preliminary study. METHODS: Relationships between MVC and clinicopathological factors were examined in 37 ICC patients. CD34 expression was analyzed using immunohistochemical methods. RESULTS: Median MVC for ICC patients was 140/mm(2), which was applied as a cutoff value. Lower MVC was significantly associated with larger tumor size, periductal infiltrating type, and advanced Japanese tumor-node-metastasis stage (p < 0.05). Univariate survival analysis identified higher carcinoembryonic antigen level, periductal infiltrating type, poor histological differentiation, and lower MVC as significantly associated with lower 5-year survival rates. The 5-year survival rate in the higher-MVC group was significantly greater than that in the lower-MVC group (44% vs. 7%, p = 0.048). According to Cox multivariate survival analysis, only periductal infiltrating type on macroscopic examination was identified as a significant independent risk factor for poor survival after hepatectomy (risk ratio 4.8; p = 0.006), not MVC (1.1; p = 0.82). CONCLUSION: Tumor MVC might offer a useful prognostic marker of ICC patient survival after hepatectomy and further investigation in a larger series is warranted
Hypothetical granulin-like molecule from Fasciola hepatica identified by bioinformatics analysis
Interleukin\u20118 released by cancer\u2011associated fibroblasts attenuates the autophagy and promotes the migration of ovarian cancer cells
The tumor microenvironment composed of a mixture of stromal cells and their secretions has a marked impact on cancer progression. In particular, soluble factors and metabolites contribute to malignancy through the dysregulation of autophagy in cancer cells. The present study investigated the effects of ovarian cancer\u2011associated fibroblasts (OVCAFs) with their secretory substances on the autophagy and migration of ovarian cancer cells. The conditioned\u2011medium (CM) of OVCAFs isolated from fresh human ovarian cancer tissues was analyzed for the levels of 27\ua0common cytokines/chemokines using a cytokine array. Autophagy in cancer cells was assessed by determining the expression of the vacuolar form of LC3 by western blot analysis and immunofluorescence. Cancer cell migration was assessed by Transwell migration assay. Interleukin (IL)\u20118 was found to be the most highly upregulated cytokine among the cytokines/chemokines found in the OVCAF\u2011CM. The role of IL\u20118 in ovarian cancer cell migration and its mechanistic link with autophagy was investigated. Recombinant human IL\u20118 (rhIL\u20118) stimulated the migration of SKOV3 and Kuramochi ovarian cancer cells, and concurrently downregulated basal autophagy, in concentration\u2011dependent manner. Compared to the CM of control counterpart normal fibroblasts isolated from benign ovaries (OVNF\u2011CM), the CM from 3 OVCAF isolates (namely, OVCAF\u20119, \u201120\ua0and\ua0\u201143) exerted effects similar to rhIL\u20118 on both cancer cell lines. The pharmacological induction of autophagy with rapamycin or metformin attenuated the pro\u2011migratory effects of IL\u20118. Neutralizing anti\u2011IL\u20118 antibody counteracted the inhibitory effect of OVCAF\u2011CM on basal autophagy. On the whole, the present study highlights the involvement of IL\u20118 released by CAFs in the ovarian tumor microenvironment in promoting cancer cell migration through the suppression of autophagy
Increased TFF1 trefoil protein expression in Opisthorchis viverrini-associated cholangiocarcinoma is important for invasive promotion
248 (PB-064) Poster CAIX and related genes predict poor survival outcomes in hormonal receptor-negative breast cancer
Pyruvate Carboxylase Is Up-Regulated in Breast Cancer and Essential to Support Growth and Invasion of MDA-MB-231 Cells.
Pyruvate carboxylase (PC) is an anaplerotic enzyme that catalyzes the carboxylation of pyruvate to oxaloacetate, which is crucial for replenishing tricarboxylic acid cycle intermediates when they are used for biosynthetic purposes. We examined the expression of PC by immunohistochemistry of paraffin-embedded breast tissue sections of 57 breast cancer patients with different stages of cancer progression. PC was expressed in the cancerous areas of breast tissue at higher levels than in the non-cancerous areas. We also found statistical association between the levels of PC expression and tumor size and tumor stage (P < 0.05). The involvement of PC with these two parameters was further studied in four breast cancer cell lines with different metastatic potentials; i.e., MCF-7, SKBR3 (low metastasis), MDA-MB-435 (moderate metastasis) and MDA-MB-231 (high metastasis). The abundance of both PC mRNA and protein in MDA-MB-231 and MDA-MB-435 cells was 2-3-fold higher than that in MCF-7 and SKBR3 cells. siRNA-mediated knockdown of PC expression in MDA-MB-231 and MDA-MB-435 cells resulted in a 50% reduction of cell proliferation, migration and in vitro invasion ability, under both glutamine-dependent and glutamine-depleted conditions. Overexpression of PC in MCF-7 cells resulted in a 2-fold increase in their proliferation rate, migration and invasion abilities. Taken together the above results suggest that anaplerosis via PC is important for breast cancer cells to support their growth and motility