Purification of lectin from larvae of the fly, Musca domestica, and in vitro anti-tumor activity in MCF-7 cells.
A new lectin was purified from larvae of the fly, Musca domestica L. (Diptera: Muscidae) (MLL-2, 38 kDa) using affinity chromatography and HPLC. Anti-tumor activity of MLL-2 was demonstrated by its inhibition of proliferation of human breast cancer (MCF-7) cells in a time-and dose-dependent manner. The results of acridine orange staining indicated that MLL-2 caused apoptosis in MCF-7 cells. DNA fragmentation in MCF-7 cells has been detected by TUNEL. Flow cytometric analysis also demonstrated that MLL-2 caused dose-dependent apoptosis of MCF-7 cells through cell arrest at G2/M phase. The MLL-2 induced a sustained increase in concentration of intracellular free calcium. Western blot revealed that MLL-2 induced apoptosis in MCF-7 cells was associated with typical apoptosis proteins in the mitochondrial pathway. In addition, the caspase-3 activity in MCF-7 cells treated with MLL-2 for 48 hours was significantly increased compared to controls (407.4 ± 3.0 vs. 1749.2 ± 6.0, P <0.01). Since MLL-2 induced apoptosis in MCF-7cells the mitochondrial pathway may be the main pathway of antitumor activity.
Ministry of Education, Key Laboratory of Food Nutrition and Safety, School of Food Science and Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, PR China. caoxh@tust.edu.cn
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Cao
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Huo
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Lu
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Mao
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Zhao
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Xu
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Wang
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Zeng
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D002118:Calcium / Q000378:metabolism; D053148:Caspase 3 / Q000378:metabolism; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects*; D002846:Chromatography, Affinity; D002851:Chromatography, High Pressure Liquid; D053938:DNA Fragmentation / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D005260:Female; D005434:Flow Cytometry; D006793:Houseflies / Q000737:chemistry*; D006801:Humans; D020287:In Situ Nick-End Labeling; D007814:Larva / Q000737:chemistry; D037102:Lectins / Q000302:isolation & purification* / Q000494:pharmacology*
D037102:Lectins; D053148:Caspase 3; D002118:Calcium