5-氨基酮戊酸光动力效应对体外培养人恶性黑素瘤细胞的物理学干预特征

Characteristics of the human malignant melanoma cultured in vitro physically intervened with 5-aminolevulinic acid photodynamic therapy

目的:探讨5-氨基酮戊酸(5-ALA)光动力学效应(5-ALA-PDT)对体外培养人恶性黑素瘤细胞的物理学干预作用,为进一步进行体内的实验研究提供实验依据。方法:实验于2004-04/11在解放军第三军医大学西南医院中心实验室将体外培养的人黑素瘤A-375细胞分别加入不同浓度的5-ALA(0.5,1,1.5,2mmol/L)孵育6h,予波长652nm半导体激光照射,照射的功率密度为15.6mW/cm2,照射剂量分别为0,2,5,10,20J/cm2,继续孵育12h,用四唑盐(MTT)比色法测定细胞存活率。结果:①5-ALA作为内源性光敏剂原卟啉IX(PpIX)的前体物被黑素细胞瘤摄取后产生过量的原卟啉IX,用652nm的激光照射能对黑素瘤A-375产生杀伤作用,其杀伤细胞的程度与5-ALA的浓度和光照剂量成正相关(P<0.01),但是当5-ALA的浓度达到1.5mmol/L以上时其杀伤细胞的作用无显著增加。②在加入5-ALA而无激发光源的情况下,细胞所产生的原卟啉IX对细胞的生存不产生明显影响(P>0.05)。结论:5-氨基酮戊酸在体外可以对黑素瘤细胞产生光动力学效应。

AIM:To investigate the physical intervention effect of 5 aminolevulinic acid(5 ALA) photodynamic therapy(5 ALA PDT) on human malignant melanoma cultured in vitro so as to provide an experimental basis for the further experiments in vivo.METHODS:The human malignant melanoma A 375 cells cultured in vitro in the central laboratory of Southwest Hospital,Third Military Medical University of Chinese PLA between April and November 2004 were incubated in a medium containing various concentrations of 5 ALA(0.5,1,1.5 and 2 mmol/L) for 6 hours and illuminated with different light doses(2,5,10 and 20 J/cm2) using a semiconductor laser at 652 nm with the energy density of 15.6 mW/cm2.After another 12 hours of incubation with 5 ALA PDT,the survival rate of human malignant melanoma A 375 cells were analyzed by methyl thiazolyl tetrazolium(MTT) assay.RESULTS:① 5 ALA as the prosoma of endogenous photosensitizer,protoporphyrin IX(PpIX), produced over expression of PpIX.The radiation of laser at 652 nm had killing effect on melanoma A 375 cells,and the killing degree was positively correlated with the concentration of 5 ALA and dosage of radiation(P< 0.01).However,when the concentration of 5 ALA was over 1.5 mmol/L,its damage to melanoma A 375 cells effect was not significantly enhanced.② The PpIX produced by 5 ALA had little effect on the survival of human malignant melanoma A 375 cells when added with 5 ALA but without excitation radiation source(P >0.05).CONCLUSION:5 ALA has photodynamic effect on melanoma in vitro.