Heat-shock protein 27 is phosphorylated in gemcitabine-resistant pancreatic cancer cells.

BACKGROUND Gemcitabine (2'-deoxy-2'-difluorodeoxycytidine: Gemzar) (GEM) appears to be the only effective anticancer drug for pancreatic cancer, but it has little impact on outcome due to a high level of inherent and acquired tumor resistance. Our previous proteomic study demonstrated that the expression of three spots of heat-shock protein 27 (HSP27) was increased in GEM-resistant pancreatic cancer cells and could play a role in determining the sensitivity of pancreatic cancer to GEM. MATERIALS AND METHODS AND RESULTS In the present study, using one-dimensional and two-dimensional Western blotting, we elucidated that these three spots of HSP27 were phosphorylated in GEM-resistant pancreatic cancer cell line, KLM1-R. CONCLUSION Phosphorylated HSP27 may play an important role in the resistance to GEM, and it could also be a possible biomarker for predicting the response of pancreatic cancer patients to treatment with GEM.