Aim: To investigate the effects of photodynamic therapy with quantum dots-arginine-glycine-aspartic acid (RGD) probe as photosensitizer on the proliferation and apoptosis of pancreatic carcinoma cells.
Methods: Construction of quantum dots-RGD probe as photosensitizer for integrin-targeted photodynamic therapy was accomplished. After cells were treated with photodynamic therapy (PDT), the proliferation of SW1990 cells were measured by methyl thiazolyl tetrazolium assay. Morphologic changes, cell cycle retardance and apoptosis were observed under fluoroscope and flow cytometry. The expression of myeloid cell leukemia-1 (Mcl-1), protein kinase B (Akt) and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) mRNA were detected by reverse transcription-polymerase chain reaction. The amount of reactive oxygen species were also evaluated by fluorescence probe.
Results: The photodynamic therapy with quantum dots-RGD probe as photosensitizer significantly inhibited cell proliferation (P < 0.01). Apoptotic cells and morphologic changes could be found under optical microscope. The FCM revealed PDT group had more significant cell apoptosis rate compared to control cells (F = 130.617, P < 0.01) and cell cycle G0/G1 and S retardance (P < 0.05) compared to control cells. The expression of Mcl-1 and Akt mRNA were down-regulated, while expression of TRAIL mRNA was up-regulated after cells treated with PDT. PDT group had more significant number of cells producing reactive oxygen species compared to control cells (F = 3262.559, P < 0.01).
Conclusion: The photodynamic therapy with quantum dots-RGD probe as photosensitizer significantly inhibits cell proliferation and increases apoptosis in SW1990 cells.
Keywords: Apoptosis; Pancreatic carcinoma; Photodynamic therapy; Reactive oxygen species; Targeted probe.