Purpose: As radiation therapy is widely used for the management of pancreatic cancer, identifying novel targets to improve the radiosensitivity of cancer cells is beneficial. Rosiglitazone, a specific peroxisome proliferator-activated receptor γ (PPARγ) agonist, has an inhibitory effect on various types of cancer cells. The purpose of this paper is to investigate the effect of rosiglitazone on the radiosensitivity of pancreatic cancer cells and the potential mechanism.
Materials and Methods: PPARγ expression in pancreatic cancer and adjacent tissues was evaluated using immunohistochemistry analysis. The viability, migration and invasion ability of PANC1 and PaTu8988 cells were detected using MTT assay, scratch-wound assay and transwell invasion assay. The effect of rosiglitazone on radiosensitivity of the cells was determined using the clonogenic assay. PANC1 cells were inoculated into BALB/c mice to establish tumors. Microarray was used to investigate changes of genes involved.
Results: Higher PPARγ expression was demonstrated in pancreatic cancer tissues compared with para-carcinoma tissues. Rosiglitazone inhibited the cell viability and enhanced the radiation-induced anti-migration and anti-invasion effect. Rosiglitazone potentiated the radiosensitivity of pancreatic cancer cells and PANC1 xenografts. Microarray analysis revealed that rosiglitazone plus radiation altered the expression of multiple genes and affected multiple pathways.
Conclusion: Rosiglitazone enhances the radiosensitivity of human pancreatic cancer cells in vitro and in vivo via complex mechanisms.
Keywords: ionizing radiation, pancreatic cancer, peroxisome proliferator-activated receptor γ, rosiglitazone, radiosensitivity