Effect of Photodynamic Therapy with BPD-MA on the Proliferation and Apoptosis of Human Bladder Cancer Cells

OBJECTIVE To explore the effect of photodynamic therapy with benzoporphyrin derivative monoacid ring A （BPD-MA） on the proliferation and apoptosis of human bladder cancer cells. METHODS Photosensitization of BPD-MA was activated with a red light laser （632.8 nm） delivered at 10 mw/cm^2 to give a total dose of 2.4 J/cm^2. Cellular proliferative activity was measured using the 3-（4,5.- dimethylethiazil-2-yl）-2,5-Diph3-eyl tetrazolium bromide （MFi-） assay and 3H-thymidine incorporation. Cell apoptosis was determined with flow cytometry analysis and the terminal deoxyuridine nicked-labeling （TUNEL） assay. RESULTS At 24 h post photodynamic treatment, photodynamic therapy significantly decreased cellular proliferative activity. The rate of apoptosis in BIU-87 cells 8 h after photodynamic treatment significantly increased up to 26.11± 2.59% as analyzed with flow cytometry. In situ labeling of DNA cleavage products with the terminal deoxyuridine nicked-labeling （TUNEL） assay reinforced these observations, BPD-MA-mediated photosensitization increased the number of TUNEL-positive cells compared to the controls. However, laser irradiation alone, BPD-MA alone and sham radiation did not affect cellular proliferative activity or apoptosis of the human bladder cancer BIU-87 cells. CONCLUSION Photodynamic therapy with BPD-MA significantly decreases cellular proliferative activity and enhances apoptosis. Therapy using this method might be a promising approach to treat patients with bladder cancer.

Apoptosis Induced by Photodynamic Therapy with Benzoporphyrin Derivative Monoacid Ring A and Exploration of its Potential Mechanism in Bladder Cancer Cells

OBJECTIVE To investigate apoptosis induced by photodynamic therapy with benzoporphyrin derivative monoacid ring A （BPD-MA） and explore its potential mechanism in human bladder cancer cells. METHODS Photosensitization of BPD-MA was activated with a red light Laser （632.8nm） delivered at 10 mW/cm^2 to give a total dose of 2.4 J/cm^2. Cellular apoptosis was measured with flow cytometry analysis and an insitu terminal deoxyuridine nick end-labeling （TUNEL） assay. Changes in mitochondrial membrane potential （△φm） were monitored by a flow cy-tometric method with Rhodamine 123 staining and the expression of bcl- 2 in BIU-87 cells was detected with immunocytochemical staining. RESULTS At 8 h following photodynamic treatment, the degree of apoptosis was significantly increased when analyzed with flow cytometry and TUNEL assay. Treatment of the BIU-87 cells by PDT with BPD-MA resulted in the collapse of the △φm and a decrease of bcl-2 expression. CONCLUSION BPD-MA-mediated PDT can effectively induce apoptosis in BIU-87 cells. The mechanism probably is through a mitochondrial-initiated pathway.

Study of wavy laminar growth of human urinary bladder cancer cell line in vitro

Objective: To observe the ordered growth behavior of human urinary bladder cancer cell line (BIU) under culture in vitro. Methods: The suspension of BIU cells was spread locally in a culture container. When the cells grew a-long the wall to form a cellular colony, macroscopic and microscopic observations complemented with measurements of the parameters including expanding diameter, expanding rate, cell shape. average cell density, average cell size. dehydrogenase activity and sensitivity to pH were conducted dynamically. Results: During cell culture, obvious laminar characteristics appeared in localized growing BIU cell colonies and there was difference between the cells of different zones in shape, size, density, dehydrogenase activity and sensitivity to pH. Conclusion: Space closing and bio-dissipation result in self-organization of BIU cells with ordered growth behavior. The present experiment offers a simple, controllable model for the study of wavy growth of human cells.