Abstract Reactive oxygen species (ROS) are generally recognized as major products in the cells that are produced during oxygen utilization, cellular breakdown, and the incomplete degradation of oxygen molecules. Deep research over the last two decades shows that ROS is the key factor for the initiation and regulation of cancer signaling pathways. The unique charisma of cancer cells is their ability to produce an elevated amount of oxidative stress and their requirement for an antioxidant defence system that differentiates the cancer cells from the normal cells. The low and high level of ROS controls the various signaling pathways associated with tumorigenesis, oncogenesis, angiogenesis, autophagy, lipid, glucose metabolism, etc. The elevated ROS level is a well-known hallmark for various cancer resulting in apoptosis by regulating pro-tumorigenic and anti-tumorigenic signaling pathways. In the meantime, the reduced ROS level contributes to cell survival, invasion, metastasis, oncogenesis, etc. The significant role of this double-edged sword ROS in cellular homeostasis, as well as carcinogenesis, will be discussed in this review. Moreover, the present review deals with the various intracellular and extracellular sources of ROS generation, the significant role of ROS, and provides a brief overview of the ROS signaling pathway in cancer.

中文翻译：

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活性氧在癌症信号通路中的矛盾作用：生理学和病理学

摘要 活性氧（ROS）通常被认为是细胞中氧利用、细胞分解和氧分子不完全降解过程中产生的主要产物。近二十年来的深入研究表明，ROS是启动和调控癌症信号通路的关键因素。癌细胞的独特魅力在于它们能够产生大量氧化应激，并且需要一种将癌细胞与正常细胞区分开来的抗氧化防御系统。低水平和高水平的 ROS 控制着与肿瘤发生、肿瘤发生、血管生成、自噬、脂质、葡萄糖代谢等相关的各种信号通路。升高的 ROS 水平是各种癌症通过调节促肿瘤发生和抗肿瘤发生信号通路导致细胞凋亡的众所周知的标志。同时，ROS 水平降低有助于细胞存活、侵袭、转移、肿瘤发生等。本综述将讨论这种双刃剑 ROS 在细胞稳态以及致癌作用中的重要作用。此外，本综述涉及 ROS 生成的各种细胞内和细胞外来源、ROS 的重要作用，并简要概述了癌症中的 ROS 信号通路。以及致癌作用，将在本综述中讨论。此外，本综述涉及 ROS 生成的各种细胞内和细胞外来源、ROS 的重要作用，并简要概述了癌症中的 ROS 信号通路。以及致癌作用，将在本综述中讨论。此外，本综述涉及 ROS 生成的各种细胞内和细胞外来源、ROS 的重要作用，并简要概述了癌症中的 ROS 信号通路。