Zhao Xiaojian, Lu Caiping, Chu Weiwei, Zhang Bing, Zhen Qiang, Wang Renfeng, Zhang Yaxiao, Li Zhe, Lv Baolei, Li Huixian, Liu Jiabao
1 Department of Thoracic Surgery, The First Hospital of Shijiazhuang, Shijiazhuang, China.
2 Department of Endocrinology, The First Hospital of Shijiazhuang, Shijiazhuang, China.
Tumour Biol. 2017 May;39(5):1010428317706215. doi: 10.1177/1010428317706215.
Non-small cell lung cancer accounts for 85% of all types of lung cancer and is the leading cause of worldwide cancer-associated mortalities. MiR-124 is epigenetically silenced in various types of cancer and plays important roles in tumor development and progression. MiR-124 was also significantly downregulated in non-small cell lung cancer patients. Glycolysis has been considered as a feature of cancer cells; hypoxia-inducible factor 1-alpha/beta and Akt are key enzymes in the regulation of glycolysis and energy metabolism in cancer cells. However, the role of miR-124 in non-small cell lung cancer cell proliferation, glycolysis, and energy metabolism remains unknown. In this research, cell proliferation was investigated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide; furthermore, glucose consumption and lactic acid production were assessed; adenosine triphosphate content and NAD/NADH were also detected. These tests were conducted using the normal non-small cell lung cancer cell line A549, which was transfected variedly with miR-mimics, miR-124 mimics, miR-124 inhibitor, pc-DNA3.1(+)-AKT1, and pc-DNA3.1(+)-AKT2 plasmid. Here, we show that miR-124 overexpression directly decreased cell growth, glucose consumption, lactate production, and energy metabolism. MiR-124 also negatively regulates glycolysis rate-limiting enzymes, glucose transporter 1 and hexokinase II. Our results also showed that miR-124 negatively regulates AKT1 and AKT2 but no regulatory effect on hypoxia-inducible factor 1-alpha/beta. Overexpression of AKT reverses the inhibitory effect of miR-124 on cell proliferation and glycolytic metabolism in non-small cell lung cancer. AKT inhibition blocks miR-124 silencing-induced AKT1/2, glucose transporter 1, hexokinase II activation, cell proliferation, and glycolytic or energy metabolism changes. In summary, this study demonstrated that miR-124 is able to inhibit proliferation, glycolysis, and energy metabolism, potentially by targeting AKT1/2-glucose transporter 1/hexokinase II in non-small cell lung cancer cells.
非小细胞肺癌占所有肺癌类型的85%，是全球癌症相关死亡的主要原因。miR-124在各种类型的癌症中发生表观遗传沉默，并在肿瘤发展和进展中发挥重要作用。miR-124在非小细胞肺癌患者中也显著下调。糖酵解被认为是癌细胞的一个特征；缺氧诱导因子1-α/β和Akt是调节癌细胞糖酵解和能量代谢的关键酶。然而，miR-124在非小细胞肺癌细胞增殖、糖酵解和能量代谢中的作用仍不清楚。在本研究中，使用3-(4,5-二甲基噻唑-2-基)-2,5-二苯基四氮唑溴盐研究细胞增殖；此外，评估葡萄糖消耗和乳酸产生；还检测三磷酸腺苷含量和NAD/NADH。这些测试使用正常的非小细胞肺癌细胞系A549进行，该细胞系分别用miR-模拟物、miR-124模拟物、miR-124抑制剂、pc-DNA3.1(+)-AKT1和pc-DNA3.1(+)-AKT2质粒进行转染。在此，我们表明miR-124过表达直接降低细胞生长、葡萄糖消耗、乳酸产生和能量代谢。miR-124还负向调节糖酵解限速酶、葡萄糖转运蛋白1和己糖激酶II。我们的结果还表明，miR-124负向调节AKT1和AKT2，但对缺氧诱导因子1-α/β没有调节作用。AKT的过表达逆转了miR-124对非小细胞肺癌细胞增殖和糖酵解代谢的抑制作用。AKT抑制阻断miR-124沉默诱导的AKT1/2、葡萄糖转运蛋白1、己糖激酶II激活、细胞增殖以及糖酵解或能量代谢变化。总之，本研究表明，miR-124能够抑制非小细胞肺癌细胞的增殖、糖酵解和能量代谢，可能是通过靶向AKT1/2-葡萄糖转运蛋白1/己糖激酶II实现的。
