[Mechanism study of tea pigment on the selective against the colony growth of preneoplastic and normal Syrian hamster embryo cells].
OBJECTIVE
To use co-cultures of SHE normal and preneoplastic cells in order to study the chemopreventive effects of doses of tea pigment (TP) from black tea on growth, proliferation, apoptosis and related regulation gene expression of normal and preneoplastic SHE cells.


METHODS
The different dose of TP (0, 0.5, 1, 5, 10 and 50 microg/ml) were used to treat the cells and the SHE cells growth growth assay and in situ apoptosis assay, in situ proliferation assay and microarray assay were used to determine the growth, proliferation, apoptosis, regulation gene expression of SHE preneoplastic cells.


RESULTS
TP induced the colony growth and proliferation of SHE normal cells and had no effect on its apoptosis. TP suppressed the growth and proliferation of SHE preneoplastic cells and induced its apoptosis. TP suppressed the growth and proliferation of SHE preneoplastic cells and induced its apoptosis in co-cultures. The pathways of cell apoptosis were up-regulated through the Caspase3, Casp ase8, P53, bad, bax, GADD45 and down-regulated mdm2 signal pathways, and the pathways of cell proliferation were regulated through blockage of G2 phase of cell cycle.


CONCLUSIONS
The suppression of transferring from preneoplastic cells to tumor cells was both directly through inducing preneoplastic cell apoptosis and indirectly through induced surrounding normal cells proliferation. This selective effect should be helpful to clarifying mechanism of TP's chempreventive effect on tumorigenecity in rodent assays.
Jiao
Zhenquan
Z
Office of Public Health Management, Chinese Center for Disease Control and Prevention, Beijing 100050, China. jiaozhenquan@hotmail.com
Ye
Hong
H
Guo
Yunchang
Y
Xu
Yong
Y
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects*; D002478:Cells, Cultured; D018920:Coculture Techniques; D006224:Cricetinae; D004622:Embryo, Mammalian / Q000166:cytology; D047108:Embryonic Development / Q000187:drug effects; D008647:Mesocricetus; D010860:Pigments, Biological / Q000302:isolation & purification / Q000494:pharmacology*; D011230:Precancerous Conditions / Q000473:pathology*; D013662:Tea / Q000737:chemistry*; D014407:Tumor Cells, Cultured
D010860:Pigments, Biological; D013662:Tea