Effect of EGF and TGF- on Cellular Adhesion and the Expression of E-cadherin and EGF Receptor in Cervical Cancer Cell Lines

Shin, J H; Moon, H S; Park, H Y; Kim, J I; Yoo, H K

Abstract

OBJECTIVE
Invasive squamous cell carcinoma is known to have undifferentiated epithelial cell, decreased cell adhesion and increased invasiveness of tumor cell and decreased expression of cell adhesive factors known as E-cadherin. And also, the over-expression of growth factor receptors, such as EGF receptor [EGFR], was observed in invasive lung cancer and esophageal cancer. The purpose of this study was to determine the effect of E-cadherin, growth factors, and their receptor in the invasion and metastasizing process of cervical cancer.
METHODS
Among the cervical cancer cell lines, CaSki, SiHa, ME-180, HeLa, HT-3 and C-33A cell lines were cultured and observed for morphological change of tumor cell. A western blot analysis was performed for detecting E-cadherin, EGFR and activated EGFR. The cervical cancer cell cultures were treated with different time duration [0, 10 min, 20 min, 30 min, 1 hr, 2 hr, 4 hr, 8 hr, 24 hr] and the change in E-cadherin, EGFR and activated EGFR expression were studied.
RESULTS
CaSki, HT-3, and ME-180 cell lines showed epithelial contact growth, while SiHa, HeLa and C-33A cell lines showed fibroblastoid growth. Through western blot analysis, E-cadherin 120 kDa band and EGFR 170 kDa band were expressed in CaSki, HT-3 and ME-180 cell line, which showed epithelial contact growth. In these 3 cell lines, expression of E-cadherin did not decrease with time dependent manner. Expression of EGFR decreased and activated EGFR expression increased in 30 minutes to 1 hour but decreased subsequently.
CONCLUSION
This study showed that the change in the activity of E-cadherin is more important in the invasion and metastasis of cervical cancer rather than the decrease of E-cadherin. The change of EGFR resulting from stimulation of growth factors such as EGF, TGF- , especially the function of activated EGFR associated in tyrosine phosphorylation is important in the signal transduction of inducing invasion of cervical cancer cell.