On the Mechanism of
Growth Inhibition of Epiregulin in A431 Epidermal Carcinoma Cells
XI Quan-Sheng, PAN Wei, ZHANG Qian, QIAN Xin-Guo, LI
Zai-Ping, GAN Ren-Bao*
( Shanghai Institute of Biochemistry, the Chinese Academy of Sciences,
Shanghai 200031, China )
Abastract Preliminary
investigation on the mechanism of the growth inhibition by recombinant
epiregulin(EPI)of epidermal carcinoma cell A431 is reported. Northern blotting
indicated that the mRNA level of cyclin dependent kinase(CDK)inhibitor, p21WAF1/CIP1,
was increased significantly after stimulation of the recombinant epiregulin
protein. Luc reporter revealed that STAT1 could bind the promoter region of p21
in response to the EPI signal. Flow cytometry assay showed that the EPI-induced
growth inhibition was not related to the apoptosis. The above results indicate
that the EPI-induced cell growth inhibition might result from the
STAT1-stimulated expression of p21, leading to the G1 arrest.
Key words growth inhibition； p21WAF1/CIP1；STAT1；apoptosis
*Corresponding author：Tel,86-21-64374430-318；Fax,86-21-64338357；e-mail,[email protected]