Study On The Acute Cytotoxic Of BEP-2D Cells Treated By CSC And The Expression Of Survivin During Its Chronic Transformation

Objective: To investigate the cytotoxicity, genotoxicity and its relevant mechanism of immortalized human bronchial epithelial cells,(BEP-2D cells) treated by cigarette smoke condensate (CSC), and explore the chemical and biological effect during the damage of cells treated by cigarette smoke, and provide the new theoretical basis for diagnosis and treatment of lung cancer.Methods: 1.Extracted the CSC: The smoke fromr the cigarette was collected by smoking machine and dissolved in serum-free cell culture medium LHC-8. 2.The acute cytotoxicity of CSC to BEP-2D cells: The survival of BEP-2DCSC determined by MTT assay,and the lesion of membrane permeability evaluated by the LDH concentration in culture medium of BEP-2DCSC,the apoptosis rate of BEP-2DCSC determined by flow cytometry,the mutation of BEP-2DCSC evaluated by the HPRT mutation. 3.The chronic malignant transformation of BEP-2D cells treated by CSC: BEP-2D cells and P15, P25, P38 of BEP-2DCSC cells were respectively chosen. The change of the survivin mRNA and protein of BEP-2D cells during its malignant transformation detected by RT-PCR( Reverse transcription PCR,RT-PCR ) and immunohistochemical method.Results :1. With the concentration increased during the acute toxicity of BEP-2D cells treated by CSC,the treaed cells had lower survival, more obvious cell membrane damaged, and higher apoptosis rate that was in good correlation with the concentration of CSC during the early stage and later stage. 2.During the chronic malignant transformation of BEP-2D cells treated by CSC, the survivin mRNA was found in BEP-2DCSC cells of P15,P25 and P38,respectively with 0.56, 0.80, and 0.81, but not in BEP-2D cells. The survivin protein was found in BEP-2D cells, but not in BEP-2DCSC cells. The levels of survivin protein expression were significant different between BEP-2D and BEP-2DCSC cells (p<0.05).Conclusion: 1.As a complicated commixture, the CSC had typical toxicity and genetoxicity. 2.The expression of survivin mRNA and protein had significant difference between the BEP-2D and BEP-2DCSC cells. The survivin may be considered as a kind of biology-marker for the diagnosis of lung cancer.