Journal name: Drug Design, Development and Therapy Article Designation: Original Research Year: 2016 Volume: 10 Drug Design, Development and Therapy Dovepress Running head verso: Al Asmari and Khan Running head recto: Scorpion venom inhibits skin tumorigenesis in mice open access to scientific and medical research DOI: http://dx.doi.org/10.2147/DDDT.S113171 Open Access Full Text Article ORIGINAL RESEARCH Investigation of in vivo potential of scorpion venom against skin tumorigenesis in mice via targeting markers associated with cancer development Abdulrahman K Al Asmari Abstract: Cancer is the leading cause of morbidity and mortality all over the world in spite Abdul Quaiyoom Khan of the advances made in its management. In this study, we investigated the in vivo anti- tumorigenic potential of the venom obtained from a medically important scorpion species Research Centre, Prince Sultan Military Medical City, Riyadh, Leiurus quinquestriatus on chemically induced skin cancer in mice. Animals were divided Saudi Arabia into five groups, with 13 animals in each group. All the treatments were given topically on the shaved dorsal surface of the skin. Animals in Group 1 received vehicle only (0.2 mL acetone). Moreover, 7,12-dimethylbenz[a]anthracene (DMBA, 400 nmol per mouse) was applied to all the animals in the remaining four groups. After 1 week, different concentra- tions of venom (17.5 μg, 35 μg, and 52.5 μg per animal) were applied to each animal in the For personal use only. Groups III–V. Thirty minutes after the application of venom, croton oil was applied on the same position where venom was administered to the animals of Groups III–V. Animals in Group II were treated as the positive control (without venom) and received croton oil as in Groups III–V. The findings of this study revealed that venom extract of L. quinquestriatus inhibits DMBA + croton oil-induced mouse skin tumor incidence and tumor multiplicity. Venom treatment also decreased the expression of proinflammatory cytokines. Immuno- histochemistry results showed a downregulation of the expression of molecular markers such as Ki-67, nuclear factor kappa-B, cyclooxygenase-2, B-cell lymphoma-2, and vascular endothelial growth factor, in venom-treated animals. Our findings suggest that the venom of L. quinquestriatus possesses in vivo anticancer potential and may be used in the develop- ment of anticancer molecules. Keywords: Leiurus quinquestriatus, skin cancer, apoptosis, immunosuppression Drug Design, Development and Therapy downloaded from https://www.dovepress.com/ by 54.70.40.11 on 24-Nov-2018 Introduction Cancer is a leading cause of death worldwide, and according to a recent global survey, 14.1 million new cancer cases and 8.2 million deaths due to cancer were recorded in 2012.1 Radiation therapy, chemotherapy, immunotherapy, surgery, and hormonal therapy are the available options for the treatment of cancer patients.2,3 However, these measures are inadequate for the management of cancer due to severe adverse effects and many other issues associated with therapy. Correspondence: Abdulrahman K A number of efforts have been made for the development of an alternative and Al Asmari effective therapeutic approach for cancer management. Various studies show that Research Centre, Prince Sultan Military attention is being given to naturally derived products for the development of novel Medical City, PO Box 7897 (777-S), Riyadh 11159, Saudi Arabia and effective chemotherapeutic drugs.4,5 The therapeutic importance of biological Tel +966 11 477 7714 ext 25100 products in the mitigation of different chronic human diseases, including cancer, has Fax +966 11 478 6601 Email [email protected] been well documented.5,6 submit your manuscript | www.dovepress.com Drug Design, Development and Therapy 2016:10 3387–3397 3387 Dovepress © 2016 Al Asmari and Khan. This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the Creative Commons Attribution – Non Commercial (unported, v3.0) License (http://creativecommons.org/licenses/by-nc/3.0/). By accessing the work you http://dx.doi.org/10.2147/DDDT.S113171 hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms (https://www.dovepress.com/terms.php). Powered by TCPDF (www.tcpdf.org) 1 / 1 Al Asmari and Khan Dovepress Various findings clearly show that toxins derived from Considering these known facts, this study was designed living organisms have strong anticancer potential.7–11 Natural to investigate the in vivo anticancer potential of the crude toxins produced by living organisms are an evolutionary venom extracted from the scorpion L. quinquestriatus, adaptation to sustain in the food chain. Such toxins play a collected from various regions of Saudi Arabia, against vital role in defense/offence and in catching of prey. It is chemically induced two-stage skin cancer development in well established that in spite of their toxicity, toxins have Swiss albino mice. To the best of the authors’ knowledge, important pharmacologically active moieties that can act as this is the first study that demonstrates the in vivo anticancer novel and effective therapeutics. potential of L. quinquestriatus scorpion venom against skin Scorpion is one of most primitive organisms known to tumorigenesis in mice. exist on the earth for millions of years and is distributed all over the world, with 1,700 known species.12 Numerous Materials and methods scorpion species (25) have been identified in different Chemicals and reagents regions of Saudi Arabia.13 Scorpion venom is a mixture of 7,12-Dimethylbenz[a]anthracene (DMBA), croton oil, different types of biologically active components, such as potassium dihydrogen phosphate, dipotassium hydrogen peptides and proteins, mucopolysaccharides, phospholi- phosphate, sodium chloride, Tris (hydroxymethyl) amin- pases, hyaluronidases, protease inhibitors, serotonin, hista- omethane, and Tween 20 were purchased from Sigma- mine, histamine-releasing peptides, nucleotides, inorganic Aldrich (St Louis, MO, USA). All other reagents used were salts, mucus, free amino acids, lipids, heterocyclic compo- of analytical grade. nents, many basic small proteins called neurotoxic peptides, and many other unknown components. Biochemical charac- Scorpion and venom collection terization of scorpion venom has shown that it is composed L. quinquestriatus, one of the medically important scorpion of peptides and proteins of 60–70 amino acid residues, which species, was collected from various regions of Saudi Arabia. are cross-linked by disulfide bridges.14,15 All the known spe- They were kept in plastic boxes and fed with mealworms and For personal use only. cies of scorpions produce different type of venoms containing water ad libitum. Venom was milked by electrical stimulation different toxic polypeptides with similar three-dimensional using the 6012 Dual Pulse Stimulator (Harvard Apparatus, configuration.14,15 Holliston, MA, USA). The recovery of venom was achieved In spite of the negative impact of scorpions on the human by mixing it with distilled water, followed by centrifugation at population, these arthropods and their venom have been 10,000 rpm for 10 minutes. The supernatant thus obtained was extensively used in the traditional medical systems and lyophilized and stored at -80°C until use. Concentrated venom folk therapies of India, Africa, and China since thousands stock was prepared in phosphatebuffered saline and sterilized of years.16,17 by passing through a 0.22 μm membrane filter. Further dilu- Various findings have shown that the components of tions were made as required for the experiments. scorpion venom have strong antibacterial, antifungal, and antiviral potential.18–23 Furthermore, a number of preclinical Animals Drug Design, Development and Therapy downloaded from https://www.dovepress.com/ by 54.70.40.11 on 24-Nov-2018 (in vitro and in vivo) and clinical research findings have Male Swiss albino mice (20–25 g) were obtained from the demonstrated that scorpion venom and its components pos- animal house facility of Research Centre, Prince Sultan sess remarkable anticancer potential against different types Military Medical City, Riyadh, Saudi Arabia. All the of cancers, including glioma, neuroblastoma, leukemia, animals were housed in the animal care facility under room lymphoma, as well as breast, lung, and prostate cancers, temperature at 22°C–25°C under a 12-hour light/12-hour due to their apoptotic, antiproliferative action coupled with dark cycle in standard cages and were given free access to the induction of cell cycle arrest and inhibition of cancer standard laboratory diet and water ad libitum. This study progression.9,11,24 The venom of Leiurus quinquestriatus was conducted in strict accordance with the guidelines and is a mixture of various components, such as enzymes, recommendations of the Guide for the Care and Use of enzyme inhibitors, and the potent neurotoxins chlorotoxin, Laboratory Animals published by the National Institutes of charybdotoxin, and so on. Chlorotoxin is known to inhibit Health. The study was approved by the ethics committee on cancer development. Available literature about the impor- the Use of Experimental Animals of the Research Centre, tance of venom