Effect Of Photodynamic Therapy On Human Breast Cancer Cell Line MDA-MB-231 In Vitro

Objective: To observe the effect of photodynamic therapy (PDT) on human breast cancer cell line MDA-MB-231 in vitro, and to select the optimization parameters(concentration of photosensitizer and intensity of laser); meanwhile to investigate action mechanisms of PDT, furthermore to offer foundation theory in bearing cancer model and the clinical therapy for breast cancer.Methods: 1 The cells were divided into four groups: the normal control before radiation without HpD, HpD alone, laser alone, and HpD in combination with laser radiation. The breast cancer cell line MDA-MB-231 cultured in vitro were treated with different concentrations of HpD and different dosages of laser, then MTT assay was applied to measure the OD 492. Then growth curve was described according above ideal parameters, and a correlation analysis of photodynamic therapy effect between photosensitizer concentration and laser intensity was made. The morphous of cells was observed under the light microscope and electron microscope after PDT at different time;2 Cell cycle blockage effect of breast cancer cell line MDA-MB-231 in HpD-PDT was observed by flow cytometry; 3 PCNA, Bax and Bcl-2 Proteinum were detected in HpD-PDT by immunocytochemistry.Results: 1 HpD-PDT(HpD 2μg/ml, 5J/cm2) can obviously inhibit the growth of breast cancer after 24 hours, but there were no influence on the growth among blank control group, single photosensitive group(HpD 2μg/ml) and single laser group (5J/cm2); 2 The result of correlation analysis:linear correlation was made between photodynamic therapy effect and photosensitizer concentration in some extent, and the same was laser intensity; 3 The morphous...