The Journal of Medical Entomology and Parasitology is one of the series issued quarterly by the Egyptian Academic Journal of Biological Sciences. It is an important specialist journal covering the latest advances in that subject. It publishes original research and review papers on all aspects of basic and applied medical entomology, parasitology and host-parasite relationships, including the latest discoveries in parasite biochemistry, molecular biology, genetics, ecology and epidemiology in the content of the biological, medical entomology and veterinary sciences. In addition to that, the journal promotes research on the impact of living organisms on their environment with emphasis on subjects such a resource, depletion, pollution, biodiversity, ecosystem…..etc. www.eajbs.eg.netProvided for non-commercial research and education use. Not for reproduction, distribution or commercial use.
A long-term blood feeder, like the Hyalomma dromedarii tick, requires extended control over all hemostatic defense mechanisms generated by the host during feeding, including blood coagulation. To overcome this, ticks have evolved numerous molecules that target proteases in the blood coagulation cascade. New insights into the role of clotting factors in the development and progression of cancer have identified anticoagulant treatment as a potential therapeutic approach. In this context, the present work assessed the anticoagulation activities of crude and fractionated salivary gland extract (SGE) prepared from semi-fed H. dromedarii females. Additionally, the antitumor effects of the potent anti-thrombin fractions were determined against colon cancer (Caco-2) and normal skin (HFB4) cells. Crude SGE significantly prolonged clotting time in prothrombin time (PT), activated partial thromboplastin time (aPTT) and thrombin time (TT) assays and inhibited thrombin in FII-activity assay. Using anion-exchange chromatography, the fractions that strongly inhibited thrombin (3.A4 and 3.A5) were eluted. Both fractions prolonged the aPTT and TT clotting times and reduced the activity of FII significantly. The protein profiles of both fractions indicated the presence of a single polypeptide band of about 99 kDa. Regarding anti-cancer potential of the tested fractions, Caco-2 cells showed reduced viability with obvious morphological changes, induced apoptosis and a reduced level of vascular endothelial growth factor (VEGF). G2/M cell cycle arrest was observed only in 3.A5-treated cells. No cytotoxic effects were observed in HFB4 cells.
Cancer is still one of the deadly diseases worldwide and the need for naturally-derived effectors is a pursued aim in health research. With the outstanding ability to bypass the host's various defense mechanisms, tick saliva constitutes an interesting rich source for the discovery of therapeutically-valuable molecules. Therefore, the present work aimed to evaluate the anti-tumor potential of Hyalomma dromedarii salivary glands extract (SGE). Three cell lines were used in this study, namely HCT116 (colorectal cancer), A549 (lung cancer) and HFB4 (normal skin) cells. MTT assay and light microscopy revealed significant dose-dependent inhibition of proliferation with obvious morphological changes in tested cell lines. Colon cells exhibited more sensitivity than lung ones, therefore they were selected for further investigations. Although cytotoxic effects were observed in treated-HFB4 cells, its IC 50 value was much higher than that of HCT116 cells. Flow cytometry analysis of treated HCT116 cells showed accumulation of cellular DNA at the G2/M phase and induction of apoptosis. In addition, RT-qPCR indicated down-regulation in the expression of vascular endothelial growth factor (VEGF), fibroblast growth factor-2 (FGF-2), transforming growth factor-β (TGF-β) and interleukin-4 (IL-4) genes. These results demonstrated that H. dromedarii SGE has antiproliferative, apoptotic and anti-angiogenic potential. Also, they open perspectives for characterization of effective molecules that could be used in developing treatments for colorectal cancer. Further investigations are required to identify the mechanisms, molecules and signaling pathways involved in the inhibitory effect of the SGE.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.