Translational Research Lab, Department of Biotechnology, Faculty of Natural Sciences, Jamia Millia Islamia, New Delhi 110025, India.
Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi 110025, India.
Life Sci. 2022 Sep 1;304:120722. doi: 10.1016/j.lfs.2022.120722. Epub 2022 Jun 15.
Cancer cells exhibit Warburg effect, characterized by increased glycolysis followed by fermentative conversion of pyruvate to lactate. Upregulation of Lactate Dehydrogenase-A (LDH-A) is elucidated to be a dominant molecular mediator of the phenomenon. Also, microRNA (miRNA) dysregulation participates in malignant progression and dissemination in several cancers. miR-16-5p is considerably reduced in lung cancers (LC), suggesting its tumor-suppressive role. However, its role in the regulation of aerobic glycolysis remains unknown. Our study aims to identify the regulatory roles of miR-16-5p/LDH-A in Non-small cell lung cancer (NSCLC).
We evaluated the differential expression of LDH-A and its prognostic potential in NSCLC tissues using online databases. We performed Tissue analysis using Immunohistochemistry (IHC); In-vitro cellular analysis including transient transfection, cellular proliferation, migration, and colony forming analysis. We also performed cell survival, metabolic, cell cycle, apoptotic, ROS generation and Immunocytochemistry (ICC) analyses to identify the role of miR-16-5p/LDH-A in aerobic glycolysis and tumorigenesis of NSCLC.
We have identified that miR-16-5p directly targets LDH-A by binding to the complementary binding regions present in its 3'-UTR region, leading to degradation, sequentially leading to reduced lactate accumulation, glucose uptake and ATP levels. Our study also demonstrated the role of lactate accumulation in promoting NSCLC tumorigenesis via activation of NF-κB signaling pathway. However, miR-16-5p mediated targeting of LDH-A downregulates the expression of NF-κB associated genes, along with increased ROS generation, apoptosis, and cell cycle arrest.
In conclusion, our findings identify miR-16-5p/LDH-A/lactate/NF-κB as an important link between metabolism and NSCLC cells tumorigenesis.
癌细胞表现出瓦博格效应，其特征为糖酵解增加，随后丙酮酸发酵转化为乳酸。研究表明，乳酸脱氢酶 A（LDH-A）的上调是该现象的主要分子介导物。此外，微 RNA（miRNA）失调参与了几种癌症的恶性进展和扩散。miR-16-5p 在肺癌（LC）中显著减少，表明其具有肿瘤抑制作用。然而，其在有氧糖酵解调节中的作用尚不清楚。我们的研究旨在确定 miR-16-5p/LDH-A 在非小细胞肺癌（NSCLC）中的调节作用。
我们使用在线数据库评估了 LDH-A 的差异表达及其在 NSCLC 组织中的预后潜力。我们进行了组织分析，包括免疫组织化学（IHC）；体外细胞分析，包括瞬时转染、细胞增殖、迁移和集落形成分析。我们还进行了细胞存活、代谢、细胞周期、凋亡、ROS 生成和免疫细胞化学（ICC）分析，以确定 miR-16-5p/LDH-A 在 NSCLC 有氧糖酵解和肿瘤发生中的作用。
我们已经确定，miR-16-5p 通过与 3'-UTR 区域中存在的互补结合区域结合，直接靶向 LDH-A，导致 LDH-A 降解，从而导致乳酸积累、葡萄糖摄取和 ATP 水平降低。我们的研究还表明，乳酸积累通过激活 NF-κB 信号通路促进 NSCLC 肿瘤发生。然而，miR-16-5p 介导的 LDH-A 靶向下调了 NF-κB 相关基因的表达，同时增加了 ROS 生成、凋亡和细胞周期停滞。
总之，我们的研究结果确定了 miR-16-5p/LDH-A/乳酸/NF-κB 作为代谢和 NSCLC 细胞肿瘤发生之间的重要联系。
