ABSTRACT
Objective To investigate whether gemcitabine (GEM) could enhance radiosensitivity of human non-small cell lung cancer cells and its related mechanism.Methods Clonogenic assay was used to analyze radiosensitivity enhancement by GEM on p53 mutant human lung adenocarcinoma cell line 973.Alterations of cell cycle distribution and apoptosis were measured by flow cytometry.Results Mild radiosesitizing effect was observed when 10 nmol/L GEM was administrated before or after irradiation.Marked radiosesitizing effect was demonstrated when 100 nmol/L GEM was administrated before or after irradiation, with much stronger effect of pre-irradiation GEM treatment.Mutation of p53 gene affected cell cycle redistribution and cell apoptosis, but had no relationship with radiosensitivity enhancement of GEM.Conclusions 100 nmol/L GEM could significantly enhance radiosensitivity of human lung cancer cells.However, this effect may not be associated with p53 gene mutation, cell cycle redistribution or cell apoptosis.