[Establishment of protein profile of human small cell lung cancer cell line NCI-H446].

BACKGROUND & OBJECTIVE: Small cell lung cancer (SCLC) is particularly aggressive, and characterized by rapid growth and early metastasis. At present, there is no data concerning SCLC two-dimensional polyacrylamide gel electrophoresis (2-DE) reference map,and its protein profiles in public databases. This study was to establish a well-resolved, reproducible 2-DE map of proteome in SCLC cell line NCI-H446, and analyze its protein profiles.

METHODS: Two-DE was applied to separate the total proteins of NCI-H446 cells, which were then silver-stained in the gel. Well-separated protein spots were selected from the gel by ImageMaster 2D analysis system. Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS), peptide map fingerprinting (PMF),and database searching were used to identify the protein spots.

RESULTS: Clear,well-resolved, reproducible 2-DE patterns of proteome in NCI-H446 cells were obtained. The average protein spots of 3 gels were 1506+/-74; and 1412+/-56 spots were matched with an average matching rate of 93.4%. The average deviation of spot position was (0.96+/-0.27) mm in IEF direction, and (1.24+/-0.41) mm in SDS-PAGE direction indicating relatively good reproducibility of the protein spots. Fifty-eight proteins were identified, certain proteins were products of oncogenes, and others were involved in cell cycle regulation, and signal transduction.

CONCLUSIONS: A reference map of NCI-H446 cells was established,certain proteins were identified by MALDI-TOF-MS and PMF. These data will be useful for establishing human SCLC proteome database.