Effects of tachyplesin and n-sodium butyrate on proliferation and gene expression of human gastric adenocarcinoma cell line BGC-823.
OBJECTIVE
To investigate the effects of tachyplesin and n-sodium butyrate on proliferation and gene expression of human gastric adenocarcinoma cell line BGC-823.


METHODS
Effects of tachyplesin and n-sodium butyrate on proliferation of BGC-823 cells were determined with trypan blue dye exclusion test and HE staining. Effects of tachyplesin and n-sodium butyrate on cell cycle were detected by flow cytometry. Protein levels of c-erbB-2, c-myc, p53 and p16 were examined by immunocytochemistry.


RESULTS
The inhibiting effects were similar after 2.0 mg/L tachyplesin and 2.0 mmol/L n-sodium butyrate treatment, the inhibitory rate of cellular growth was 62.66% and 60.19% respectively, and the respective maximum mitotic index was decreased by 49.35% and 51.69% respectively. Tachyplesin and n-sodium butyrate treatment could markedly increase the proportion of cells at G(0)/G(1) phase and decrease the proportion at S phase. The expression levels of oncogene c-erbB-2, c-myc, and mtp53 proteins were down-regulated while the expression level of tumor suppressor gene p16 protein was up-regulated after the treatment with tachyplesin or n-sodium butyrate. The effects of 1.0 mg/L tachyplesin in combination with 1.0 mmol/L n-sodium butyrate were obviously superior to their individual treatment in changing cell cycle distribution and expression of c-erbB-2, c-myc, mtp53 and p16 protein. The inhibitory rate of cellular growth of BGC-823 cells after combination treatment was 62.29% and the maximum mitotic index was decreased by 51.95%.


CONCLUSIONS
Tachyplesin as a differentiation inducer of tumor cells has similar effects as n-sodium butyrate on proliferation of tumor cells, expression of correlative oncogene and tumor suppressor gene. It also has a synergistic effect on differentiation of tumor cells.
Shi
Song-Lin
SL
The Key Laboratory of Chinese Ministry of Education for Cell Biology & Tumor Cell Engineering, School of Life Science, Xiamen University, Xiamen 361005, Fujian Province, China.
Wang
Yong-Ye
YY
Liang
Ying
Y
Li
Qi-Fu
QF
D000230:Adenocarcinoma / Q000188:drug therapy / Q000235:genetics / Q000473:pathology*; D023181:Antimicrobial Cationic Peptides / Q000494:pharmacology* / Q000627:therapeutic use; D002087:Butyrates / Q000494:pharmacology* / Q000627:therapeutic use; D002453:Cell Cycle / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects*; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000032:analysis / Q000235:genetics; D004268:DNA-Binding Proteins / Q000494:pharmacology* / Q000627:therapeutic use; D004357:Drug Synergism; D005434:Flow Cytometry; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects*; D006801:Humans; D007150:Immunohistochemistry; D008940:Mitotic Index; D010456:Peptides, Cyclic / Q000494:pharmacology* / Q000627:therapeutic use; D016271:Proto-Oncogene Proteins c-myc / Q000032:analysis / Q000235:genetics; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis / Q000235:genetics; D013274:Stomach Neoplasms / Q000188:drug therapy / Q000235:genetics / Q000473:pathology*; D016159:Tumor Suppressor Protein p53 / Q000032:analysis / Q000235:genetics
D023181:Antimicrobial Cationic Peptides; D002087:Butyrates; D019941:Cyclin-Dependent Kinase Inhibitor p16; D004268:DNA-Binding Proteins; D010456:Peptides, Cyclic; D016271:Proto-Oncogene Proteins c-myc; D018719:Erb-b2 Receptor Tyrosine Kinases; D016159:Tumor Suppressor Protein p53; C489427:MYC protein, human; C057636:tachyplesin peptide, Tachypleus tridentatus