Franskevych D V, Prylutska S V, Grynyuk I I, Grebinyk D M, Matyshevska O P
Taras Shevchenko National University of Kyiv, Kyiv 01601, Ukraine.
Exp Oncol. 2015 Sep;37(3):187-91.
To evaluate the viability of leukemic cells sensitive (L1210S) and resistant (L1210R) to cisplatin, ROS production and free cytosolic Ca(2+) concentration under treatment with cisplatin or its combination with photoexcited fullerene C60.
Cell viability was assessed by the MTT reduction assay. Light-emitting diode lamp (2.45 J/cm(2)) was used for photoexcitation of intracellular accumulated fullerene C60. Free cytosolic calcium concentration ([Ca(2+)]i) and ROS production in cells were estimated with the use of fluorescent probes Indo-1 and 2',7'-dichlorodihydrofluorescein diacetate (DCF-DA), respectively.
It is shown that viability of L1210R cells wasn't changed under treatment with cisplatin in concentration range 0.1-10 μg/ml. 50% and 30% decrease of L1210S cells were observed after 24 h of incubation with cisplatin at concentrations 5 and 1 μg/ml, respectively. Intensification of extranuclear cytotoxic effects (ROS production and [Ca(2+)]i increase) after treatment with 1 μg/ml was detected in L1210S, but not in L1210R cells. The most strongly pronounced increase of ROS production and [Ca(2+)]i in both L1210 cell lines was revealed in dynamics after combined treatment with cisplatin (1 μg/ml) and photoexcited fullerene C60 (10(-5) M) and was followed by decreased viability of not only L1210S, but of L1210R cells as well..
Combined treatment with photoexcited C60 and cisplatin allowed to decrease effective concentration of cisplatin against parental L1210 cells and to increase sensibility of resistant cells to the drug.
评估顺铂敏感（L1210S）和耐药（L1210R）白血病细胞在顺铂或其与光激发富勒烯C60联合处理下的活力、活性氧（ROS）生成及游离胞质钙（Ca²⁺）浓度。
采用MTT还原法评估细胞活力。用发光二极管灯（2.45 J/cm²）对细胞内积累的富勒烯C60进行光激发。分别使用荧光探针Indo-1和2',7'-二氯二氢荧光素二乙酸酯（DCF-DA）估算细胞内游离钙浓度（[Ca²⁺]i）和ROS生成。
结果显示，在0.1 - 10 μg/ml浓度范围内，顺铂处理下L1210R细胞的活力未发生变化。分别用5 μg/ml和1 μg/ml顺铂孵育24 h后，L1210S细胞活力分别下降50%和30%。在L1210S细胞中检测到用1 μg/ml顺铂处理后核外细胞毒性作用增强（ROS生成及[Ca²⁺]i增加），但L1210R细胞未出现此现象。在L1210两种细胞系中，与顺铂（1 μg/ml）和光激发富勒烯C60（10⁻⁵ M）联合处理后，最显著的ROS生成及[Ca²⁺]i增加出现，随后不仅L1210S细胞活力下降，L1210R细胞活力也下降。
光激发C60与顺铂联合处理可降低顺铂对亲本L1210细胞的有效浓度，并增加耐药细胞对该药物的敏感性。
