Epidermal growth factor receptor blocker C225 increases chemosensitivity and radiosensitivity of Docetaxel resistant human lung adenocarcinoma cell line SPC-A-1/docetaxel / 中国肿瘤生物治疗杂志

ABSTRACT

Objective:To investigate the modulating effects of anti-epidermal growth factor monoclonal antibody Cetux- imab(C225)on the ehemosensitivity and radiosensitivity in a Docetaxel-resistant human lung adenocarcinoma cell line SPC-A-1/doeetaxel.Methods:Radiosensitivity of SPC-A-1/docetaxel was determined by clone formation experiment and quantified by calculating the enhancement ratio(ER).The growth inhibition of SPC-A-1/docetaxel cell line caused by C225 or combination of C225 and Docetaxel in different orders was detected by MTT assay.The effect of C225 on cell cy- cle distribution and apoptosis was determined by flow cytometry.Results:C225 combined with radiation significantly de- creased the number of the cell clones than radiation alone;the D_0 values were 1.73 Gy for the former and 2.39 Gy for the latter,and the enhancement ratio was 1.38.C225 alone at concentration up to 1000?g/ml for 48h had neither cytotoxic nor eytostatie effect on SPC-A-1/docetaxel in vitro.C225 administration followed by Docetaxel significantly decreased the ICw of Docetaxel(85.2?g/ml vs 128.7?g/ml).Flow cytometry demonstrated that C225 exposure induced apoptosis of SPC-A-1/docetaxel cells in a time-dependent manner.The cell in the G_0/G_1 fraction increased from(43.80?4.46)% to (60.50?6.57)%(P