Płonka Justyna, Latocha Małgorzata, Kuśmierz Dariusz, Zielińska Aleksandra
Department of Cell Biology, School of Pharmacy, Medical University of Silesia, Sosnowiec, Poland.
Adv Clin Exp Med. 2015 Jan-Feb;24(1):37-46. doi: 10.17219/acem/38152.
Breast cancer is the most common malignant tumour in women in the whole world. Despite significant developments in the early diagnosis of breast cancer, there is no effective method which would assure total recovery of the patient. Currently available clinical data and laboratory tests indicate a possibility to introduce photodynamic therapy (PDT) to the supplementary treatment of breast cancer.
The aim of this study was to assess the influence of PDT with Photolon as a photosensibilizator on the expression of apoptosis associated genes (BCL-2, BAX, TP53) in human breast cancer cell lines, preceded by assessment of survivorship and proliferative activity in the tested cells after PDT.
In the present study human breast cancer cell lines MCF-7 and T-47D were used. Photolon (chlorin e6 complex: PVP 1:1) was used as a photosensitizer. Assessments of survivorship and proliferative activity of cells under the influence of PDT (WST-1 test) were conducted along with the expression of selected genes involved in the process of apoptosis: BCL-2, BAX, TP53 (RT-QPCR).
PDT limited both survivorship and proliferative activity of breast cancer cells in the two tested lines. In case of T-47D cell line was found increase of BAX and BCL-2 genes expression after PDT and sustained activity of TP53 gene. Conversely, in MCF-7 cell line a decrease in expression was found for both BAX and TP53 genes, but also an increase of BCL-2 gene expression.
A progressing decrease (24, 48 and 72 h after PDT) in the count of culture cells, which suggests the occurrence of apoptosis initiated by a photodynamic reaction with simultaneous increase of BCL-2/BAX index, indicates activation of a different endogenous apoptosis pathway than the one examined, namely pointing to suicidal death of cells after PDT.
乳腺癌是全球女性中最常见的恶性肿瘤。尽管乳腺癌的早期诊断有了显著进展，但尚无确保患者完全康复的有效方法。目前可用的临床数据和实验室检测表明，有可能将光动力疗法（PDT）引入乳腺癌的辅助治疗。
本研究的目的是评估以Photolon作为光敏剂的光动力疗法对人乳腺癌细胞系中凋亡相关基因（BCL-2、BAX、TP53）表达的影响，在此之前先评估光动力疗法后受试细胞的存活率和增殖活性。
本研究使用了人乳腺癌细胞系MCF-7和T-47D。Photolon（二氢卟吩e6复合物：聚乙烯吡咯烷酮1:1）用作光敏剂。在光动力疗法的影响下对细胞的存活率和增殖活性进行评估（WST-1试验），同时评估参与凋亡过程的选定基因的表达：BCL-2、BAX、TP53（逆转录定量聚合酶链反应）。
光动力疗法限制了两个受试细胞系中乳腺癌细胞的存活率和增殖活性。在T-47D细胞系中，发现光动力疗法后BAX和BCL-2基因表达增加，且TP53基因持续活跃。相反，在MCF-7细胞系中，发现BAX和TP53基因表达均下降，但BCL-2基因表达增加。
培养细胞数量的逐渐减少（光动力疗法后24、48和72小时），这表明发生了由光动力反应引发的凋亡，同时BCL-2/BAX指数增加，表明激活了一条与所检测的不同的内源性凋亡途径，即表明光动力疗法后细胞发生自杀性死亡。
