Screening differential membrane proteins of cultured breast cancer cell lines

Objective To screen differential membrane proteins by comparing protein fingerprinting between breast cancer and normal breast epithelial cell lines cultured in vitro,which may lay a foundation for sub-cellular protein biomarker of breast cancer.Methods Membrane proteins of two breast cancer cell lines MDA-MB-231,MCF-7 and one normal breast epithelium cell line HBL-100 were extracted,and the protein fingerprinting were measured by surface enhanced laser desorption/ionization time-of-flight mass spectrometry(SELDI-TOF-MS) for 50 times.Differential proteins were analyzed and screened by Bio-maker Wizard Software.Results About 100 protein peaks were observed on protein fingerprinting spectra ranged from 2 kD to 100 kD,among which 32 and 34 membrane protein peaks of them showed significant difference between MDA-MB-231 and MCF-7 when compared with HBL-100(P0.05).Protein peaks at 7.8 kD,8.3 kD and 8.8 kD were down-regulated in both breast cancer cell lines,while protein peaks at 9.6 kD were up-regulated.Conclusion SELDI-TOF-MS can detect membrane proteins of breast cancer cell lines accurately and sensitively,which applies a new method for subcellular protein biomarkers of breast cancer.