Önder Gözde Özge, Sezer Gülay, Özdamar Saim, Yay Arzu
Faculty of Medicine, Department of Histology and Embryology, Erciyes University, Kayseri, Turkey.
Genome and Stem Cell Center, Erciyes University, Kayseri, Turkey.
Fundam Clin Pharmacol. 2022 Dec;36(6):1038-1056. doi: 10.1111/fcp.12813. Epub 2022 Jul 13.
The goal of this work was to see how melatonin affected Bax and Bcl-2 expression, as well as apoptosis and autophagy, in MCF-7 and MDA-MB-231 breast cancer cell lines, which have distinct hormonal sensitivities. In this study, to investigate the IC50 value of melatonin, varied melatonin concentrations were administered to MCF-7 and MDA-MB-231 breast cancer cell lines. Moreover, cytotoxic activities were analyzed through MTT analysis. Five subgroups were created for both cell lines: control, IC50-MeL, hIC50-MeL, DMSO1, and DMSO2. To evaluate the apoptotic effect of melatonin, immunofluorescence staining methods of TUNEL, Bax, and Bcl-2 were used, and to examine the effects of autophagy, immunofluorescence staining methods of Beclin-1, LC3, and p62 were used. In vitro results revealed upregulation of the expression of TUNEL and Bax in both MCF-7 and MDA-MB-231 cell lines regarding dose and time, but downregulation of Bcl-2 expression. Moreover, autophagy results were consistent with in vitro apoptosis results in both MCF-7 and MDA-MB-231 cell lines. We determined that the expressions of the autophagy markers Beclin-1, LC3, and p62 were increased. Our findings indicate that treatment of breast cancer cells with melatonin increased the inhibitory effect of melatonin on cell growth through both apoptosis and autophagy in vitro. Consequently, it was concluded that melatonin might adjust the expression balance of markers that have a role in cell death mechanisms and significantly promote these mechanisms. Therefore, melatonin can inhibit the growth of breast cancer cells by inducing cell death.
本研究旨在观察褪黑素对激素敏感性不同的MCF-7和MDA-MB-231乳腺癌细胞系中Bax和Bcl-2表达、细胞凋亡及自噬的影响。本研究中，为探究褪黑素的半数抑制浓度（IC50）值，将不同浓度的褪黑素作用于MCF-7和MDA-MB-231乳腺癌细胞系。此外，通过MTT分析检测细胞毒性活性。两种细胞系均分为五个亚组：对照组、IC50褪黑素组、半数抑制浓度（hIC50）褪黑素组、二甲基亚砜1（DMSO1）组和二甲基亚砜2（DMSO2）组。为评估褪黑素的凋亡作用，采用TUNEL、Bax和Bcl-2免疫荧光染色法；为检测自噬作用，采用Beclin-1、LC3和p62免疫荧光染色法。体外实验结果显示，MCF-7和MDA-MB-231细胞系中TUNEL和Bax的表达随剂量和时间增加而上调，但Bcl-2表达下调。此外，自噬结果与MCF-7和MDA-MB-231细胞系的体外凋亡结果一致。我们发现自噬标志物Beclin-1、LC3和p62的表达增加。我们的研究结果表明，褪黑素处理乳腺癌细胞可通过体外凋亡和自噬增强其对细胞生长的抑制作用。因此，得出结论：褪黑素可能调节参与细胞死亡机制的标志物的表达平衡，并显著促进这些机制。所以，褪黑素可通过诱导细胞死亡抑制乳腺癌细胞生长。
