title: Bioassay-guided isolation of a novel protein with antitumor activity from Trachyrhamphus serratus (Syngnathidae).
abstract: A novel protein with antitumor activity, Hailongin, was purified from the aqueous extract of the whole body of Trachyrhamphus serratus, which is commonly used in traditional Chinese medicine, by bioassay-guided fractionation. Hailongin exhibited strong inhibition of proliferation of the tested human cell lines, such as A549, HeLa, LoVo and CCRF-CEM. The IC(50) values of Hailongin ranged from 5.4 to 25.7 μ/mL. An in vivo study showed that the growth of implanted S-180 solid tumors in mice was significantly inhibited by Hailongin treatment, while the immunological function of the tumor-bearing mice was enhanced. The molecular weight and the isoelectric point of Hailongin were 57.074 kDa (by MALDI-TOF-MS) and 6.2 (by isoelectric focusing-polyacrylamide gel electrophoresis), respectively. Seventeen amino acids were identified in Hailongin. The acidic amino acids accounted for the majority of Hailongin's amino acid composition. The N-terminal amino acid sequence of Hailongin was determined to be IVPYSHNAGNKGLTQMR and showed no significant homology with known proteins.
authors: School of Pharmacy, Shanghai Jiao Tong University, Shanghai 200240, China.
authors: Meng Yue
authors: MY
authors: Wang
authors: Sun Xing
authors: SX
authors: Qin
authors: Fen
authors: F
authors: He
authors: Xiaobo
authors: X
authors: Li
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000737:chemistry; D000818:Animals; D000970:Antineoplastic Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D001681:Biological Assay; D045744:Cell Line, Tumor; D004591:Electrophoresis, Polyacrylamide Gel; D029941:Fish Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D006801:Humans; D020128:Inhibitory Concentration 50; D007526:Isoelectric Point; D008297:Male; D008516:Medicine, Chinese Traditional; D051379:Mice; D008813:Mice, Inbred ICR; D008970:Molecular Weight; D012510:Sarcoma 180 / Q000188:drug therapy* / Q000473:pathology; D023701:Smegmamorpha / Q000378:metabolism*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D000596:Amino Acids; D000970:Antineoplastic Agents; D029941:Fish Proteins; C562033:hailongin