TY - JOUR ID - 89236 TI - The Venom of Philippine Tarantula (Theraphosidae) Contains Peptides with Pro-Oxidative and Nitrosative-Dependent Cytotoxic Activities against Breast Cancer Cells (MCF-7) In Vitro JO - Asian Pacific Journal of Cancer Prevention JA - APJCP LA - en SN - 1513-7368 AU - Lopez, Simon Miguel M AU - Aguilar, Jeremey S AU - Fernandez, Jerene Bashia B AU - Lao, Angelic Gayle J AU - Estrella, Mitzi Rain R AU - Devanadera, Mark Kevin P AU - Mayor, Anna Beatriz R AU - Guevarra Jr, Leonardo A AU - Santiago-Bautista, Myla R AU - Nuneza, Olga M AU - Santiago, Librado AD - Department of Biochemistry, Faculty of Pharmacy, University of Santo Tomas, Manila, Philippines. AD - Research Center for Natural and Applied Sciences, University of Santo Tomas, Manila Philippines. AD - Department of Biochemistry, Faculty of Pharmacy, University of Santo Tomas, Manila, Philippines. AD - Department of Biological Sciences, College of Science and Mathematics, Mindanao State University – Iligan Institute of Technology, Iligan City, Philippines. Y1 - 2020 PY - 2020 VL - 21 IS - 8 SP - 2423 EP - 2430 KW - Philippine tarantula KW - spider venom KW - Cytotoxicity KW - MCF-7 KW - oxidative stress DO - 10.31557/APJCP.2020.21.8.2423 N2 - Background: Breast cancer is a multifactorial disease that affects women worldwide. Its progression is likely to be executed by oxidative stress wherein elevated levels of reactive oxygen and nitrogen species drive several breast cancer pathologies. Spider venom contains various pharmacological peptides which exhibit selective activity to abnormal expression of ion channels on cancer cell surface which can confer potent anti-cancer activities against this disease. Methods: Venom was extracted from a Philippine tarantula by electrostimulation and fractionated by reverse phase-high performance liquid chromatography (RP-HPLC). Venom fractions were collected and used for in vitro analyses such as cellular toxicity, morphological assessment, and oxidative stress levels. Results: The fractionation of crude spider venom generated several peaks which were predominantly detected spectrophotometrically and colorimetrically as peptides. Treatment of MCF-7 cell line of selected spider venom peptides induced production of several endogenous radicals such as hydroxyl radicals (•OH), nitric oxide radicals (•NO), superoxide anion radicals (•O2−) and lipid peroxides via malondialdehyde (MDA) reaction, which is comparable with the scavenging effects afforded by 400 µg/mL vitamin E and L-cysteine (p<0.05). Concomitantly, the free radicals produced decrease the mitochondrial membrane potential and metabolic activity as detected by rhodamine 123 and tetrazolium dye respectively (p>0.05). This is manifested by cytotoxicity in MCF-7 cells as seen by increase in membrane blebbing, cellular detachment, caspase activity and nuclear fragmentation. Conclusion: These data suggest that the Philippine tarantula venom contains peptide constituents exhibiting pro-oxidative and nitrosative-dependent cytotoxic activities against MCF-7 cells and can indicate mechanistic insights to further explore its potential application as prooxidants in cancer therapy.   UR - https://journal.waocp.org/article_89236.html L1 - https://journal.waocp.org/article_89236_e9ec515c4ef78ab412529f9eb6393713.pdf ER -