[Tachyplesin-induced differentiation of human hepatocarcinoma cell line SMMC-7721].
OBJECTIVE
The study on antitumor activities of marine bioactive substances is an important field in exploiting marine bioactive substances and antitumor drugs. And the induction of tumor cell differentiation is a new strategy for drug therapy of tumors. So the authors used tachyplesin, a marine bioactive substance, to investigate its effects on the differentiation of human hepatocarcinoma SMMC-7721 cells for further studying its antitumor activities and mechanisms.


METHODS
Tachyplesin, which was isolated from hemocytes of horseshoe crab (Tachypleus tridentatus), was used to treat human hepatocarcinoma SMMC-7721 cells. Light microscopy and transmission electron microscopy were applied to examine the changes in morphology and ultrastructure of SMMC-7721 cells, respectively. The activities of alkaline phosphatase or the expression of AFP and PCNA were assessed by cytochemistry or immunocytochemistry.


RESULTS
In the cells treated with 3.0 micrograms/ml tachyplesin, the morphology and ultrastructure returned to be normal, the activity of alkaline phosphatase was decreased and the levels of AFP and PCNA were downregulated.


CONCLUSIONS
Tachyplesin might effectively reverse the malignant morphology and ultrastructure, change the activity of enzyme and the levels of antigens associated with hepatocarcinoma cell, and induce the differentiation of the human hepatocarcinoma SMMC-7721 cells.
Li
Qi-fu
QF
Laboratory of Cell Biology, Key Laboratory of Ministry of Education for Cell Biology & Tumor Cell Engineering, School of Life Sciences, Xiamen University, Xiamen 361005, P. R. China. chifulee@163.net
Ouyang
Gao-liang
GL
Liu
Qing-rong
QR
Hong
Shui-gen
SG
D000469:Alkaline Phosphatase / Q000187:drug effects / Q000378:metabolism; D000818:Animals; D023181:Antimicrobial Cationic Peptides; D000970:Antineoplastic Agents / Q000494:pharmacology*; D006528:Carcinoma, Hepatocellular; D002454:Cell Differentiation / Q000187:drug effects; D004268:DNA-Binding Proteins / Q000494:pharmacology*; D006737:Horseshoe Crabs; D006801:Humans; D008113:Liver Neoplasms; D010456:Peptides, Cyclic / Q000494:pharmacology*; D018809:Proliferating Cell Nuclear Antigen / Q000096:biosynthesis; D014407:Tumor Cells, Cultured; D000509:alpha-Fetoproteins / Q000096:biosynthesis
D023181:Antimicrobial Cationic Peptides; D000970:Antineoplastic Agents; D004268:DNA-Binding Proteins; D010456:Peptides, Cyclic; D018809:Proliferating Cell Nuclear Antigen; D000509:alpha-Fetoproteins; C057636:tachyplesin peptide, Tachypleus tridentatus; D000469:Alkaline Phosphatase