Deka Suman Jyoti, Mamdi Narsimha, Manna Debasis, Trivedi Vishal
Malaria Research Group, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, India.
Laboratory of Biological Chemistry, Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati, India.
J Breast Cancer. 2016 Dec;19(4):358-371. doi: 10.4048/jbc.2016.19.4.358. Epub 2016 Dec 23.
The protein kinase C (PKC) family of serine-threonine kinases plays an important role in cancer cell progression. Thus, molecules that target PKC have potential as anticancer agents. The current study aims to understand the treatment of breast cancer cells with alkyl cinnamates. We have also explored the mechanistic details of their anticancer action and the underlying molecular signaling.
3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was performed to measure the viability of MDAMB-231 breast cancer cells to assess the anticancer activity of these compounds. In addition, flow cytometry was performed to study the effect of alkyl cinnamates on the cell cycle and apoptosis. Immunoblotting and immunofluorescence techniques were performed to study PKC translocation, cytochrome c release, and modulation of the mitochondrial membrane potential in breast cancer cells targeted with alkyl cinnamates.
The PKC agonist DM-2-8 translocated 16.6%±1.7% PKCα from cytosol to the plasma membrane and showed excellent anticancer activity with an half maximal inhibitory concentration (IC) of 4.13±0.27 µg/mL against cancer cells. The treated cells had an abnormal morphology and exhibited cell cycle defects with G2/M arrest and reduced S phase. Cancer cells treated with DM-2-3, DM-2-4, or DM-2-8 underwent apoptosis as the major pathway of cell death, further confirmed by genomic DNA fragmentation. Furthermore, the mitochondrial membrane potential was perturbed, indicating involvement of the mitochondrial pathway of apoptosis. Immunolocalization studies revealed cytochrome c release from mitochondria to cytosol. Cancer cells treated with DM-2-8 and curcumin showed activation of caspase-9 and caspase-3 as downstream molecular components of the apoptotic pathway. Alkyl cinnamates also caused oxidative stress, which regulates the apoptotic machinery (DNA fragmentation), cell death, and morphological abnormalities in cancer cells.
Alkyl cinnamates specifically target cancer cells through induction of PKC translocation and the mitochondrial pathway of apoptosis, and could be promising anticancer drugs.
丝氨酸 - 苏氨酸激酶的蛋白激酶C（PKC）家族在癌细胞进展中起重要作用。因此，靶向PKC的分子具有作为抗癌剂的潜力。当前研究旨在了解用肉桂酸烷基酯处理乳腺癌细胞的情况。我们还探索了其抗癌作用的机制细节以及潜在的分子信号传导。
进行3 -（4,5 - 二甲基噻唑 - 2 - 基）-2,5 - 二苯基四氮唑溴盐（MTT）测定以测量MDAMB - 231乳腺癌细胞的活力，以评估这些化合物的抗癌活性。此外，进行流式细胞术以研究肉桂酸烷基酯对细胞周期和细胞凋亡的影响。进行免疫印迹和免疫荧光技术以研究肉桂酸烷基酯靶向的乳腺癌细胞中PKC易位、细胞色素c释放和线粒体膜电位的调节。
PKC激动剂DM - 2 - 8使16.6%±1.7%的PKCα从细胞质转移到质膜，并显示出优异的抗癌活性，对癌细胞的半数最大抑制浓度（IC）为4.13±0.27μg/mL。处理后的细胞具有异常形态，并表现出细胞周期缺陷，G2/M期阻滞且S期减少。用DM - 2 - 3、DM - 2 - 4或DM - 2 - 8处理的癌细胞经历凋亡作为细胞死亡的主要途径，基因组DNA片段化进一步证实了这一点。此外，线粒体膜电位受到干扰，表明凋亡的线粒体途径参与其中。免疫定位研究揭示了细胞色素c从线粒体释放到细胞质中。用DM - 2 - 8和姜黄素处理的癌细胞显示出作为凋亡途径下游分子成分的caspase - 9和caspase - 3的激活。肉桂酸烷基酯还引起氧化应激，其调节癌细胞中的凋亡机制（DNA片段化）、细胞死亡和形态异常。
肉桂酸烷基酯通过诱导PKC易位和凋亡的线粒体途径特异性靶向癌细胞，可能是有前景的抗癌药物。
