Effect Of Photodynamic Therapy Mediated By HPD On Killing And Apoptosis Of Lung Cancer

Objective To investigate the killing effect and apoptosis of hematoporphyrin derivative mediated photodynamic therapy(HPD-PDT)on human pumonary adenocarcinoma cell line A549.Method The A549 cells were incubated at random with different concentrations of hematoporphyrin derivatives(HPD)(5,10,12,15,20μg/ml)for 4h,and then illuminated by laser at avarious energy densites(25,50,75,100mw/cm2).And meanwhile,the photosensitizer group(with hematoporphyrin but without laser irradiation),laser irradiation group(with laser irradiation but without photosensitizer)and blank group(without photosensitizer and laser irradiation)were selscted as control groups.The cell viability was detected by CCK8,The apoptosis of A549 cells were observed by Hoechst33258 staining.The expression levels of Bcl-2、Bax、survivin and caspase-3 m RNA were measured by reverse transcription polymerase chain reaction(RT-PCR).Results hematoporphyrin derivative mediated photodynamic therapy(HPD-PDT)proved no killing effect on the pulmonary adenocarcinoma cell line A549 with photosensitizer or laser irradiation alone.the combined of photosensitizer and laser irradiation obviously inhibited the proliferation of the A549 cells.Furthermore,the killing effect markedly increased with the concentration of the photosensitizer and the density of laser exposure.CCK8 showed that the A549 cell viability in group 15μg/ml,group 20μg/ml was significant lower than than those in other groups,Comparing with the blank group,the results were(t=2.404,P=0.043)and(t=3.109,P=0.014)respectively.The A549 cell activity in group 50 m W/cm2,group 75 m W/cm2 and group 100 m W/cm2 decreased significantly compared with the control group,And the difference was statistically significant.Honchest 33258 staining showed that HPD-PDT could promote the apoptosis of the A549 cells,including chromatin condensation,nucleus hyperchromatin.The Annexin V-FITC/PI double staining revealed the apoptosis rates in the groups significantly increased,which were(2.529±0.14)%,(2.372±0.17)%,(2.462±0.28)% and(35.837±4.15)% respectively treated with the blank group 、 laser irradiation group 、photosensitizer group and HPD-PDT group.Comparing with the blank group,the results of HPD-PDT group were(t=-19.632,P < 0.05),and the apoptosis rate has a significant differences in each group(F=385.369,P < 0.05).RT-PCR analysis showed that the expression of Caspase-3 and Bax m RNA were significantly up-regulated in the HPD-PDT group,However,the bcl-2 and survivin m RNA expression were significantly down-regulated in the the HPD-PDT group.Conclusion HPD-PDT exhibits potent killing effect on human pumonary adenocarcinoma cell line A549 in vitro,which is associated with Caspase-3,Bcl-2,survivin and Bax to a large extent.