[Establishment of a bortezomib-resistant myeloma cell line and differential proteins analysis by MALDI-OF-MS].

Objective: To establish a bortezomib-resistant myeloma cell line and to investigate its mechanism.

Methods: Bortezomib-resistant NCI-H929 cell line (NCI-H929B) was obtained by stepwise increasing extracellular concentrations of bortezomib over a period of 8 months. The biological characteristics of NCI-H929 and NCI-H929B were observed. Proteins from NCI-H929B cell and NCI-H929 cell were extracted, run on two-dimensional gel electrophoresis. Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) and mass spectrometry (MS) were used to identify proteins. Western blot was used to further verify differential proteins.

Result: Bortezomib-resistant cell line NCI-H929B was established. NCI-H929B exhibits a 23.5-fold level of resistance to bortezomib as compared to the parental cell line NCI-H929. There were no significant differences in cellular biology of cell growth curve and cell cycle distribution between NCI-H929 and NCI-H929B cell lines.Whole proteins of NCI-H929 and NCI-H929B myeloma cell lines were extracted by two-dimensional gel electrophoresis. Gel-image analysis revealed that there were 17 differential protein spots. A total of 14 differential protein spots were successfully identified by MALDI-TOF-MS. The result of Western blot was consistent with 2-DE.

Conclusion: A bortezomib-resistant human myeloma cell line NCI-H929B was successfully established. The differentially expression of proteomes may be useful for study of the bortezomib-resistant mechanisms and the molecular markers of MM.