Li Chunxia, Zhang Guifeng, Zhao Lei, Ma Zhijun, Chen Hongbing
Department of Oncology, Yidu Central Hospital, Weifang, Shandong, 262500, China.
Department of Oncology Nursing, Yidu Central Hospital, Weifang, Shandong, 262500, China.
World J Surg Oncol. 2016 Jan 20;14(1):15. doi: 10.1186/s12957-016-0769-9.
Nearly a century ago, Otto Warburg made the ground-breaking observation that cancer cells, unlike normal cells, prefer a seemingly inefficient mechanism of glucose metabolism: aerobic glycolysis, a phenomenon now referred to as the Warburg effect. The finding that rapidly proliferating cancer cells favors incomplete metabolism of glucose, producing large amounts of lactate as opposed to synthesizing ATP to sustain cell growth, has confounded scientists for years. Further investigation into the metabolic phenotype of cancer has expanded our understanding of this puzzling conundrum, and has opened new avenues for the development of anti-cancer therapies. Enhanced glycolytic flux is now known to allow for increased synthesis of intermediates for sustaining anabolic pathways critical for cancer cell growth. Alongside the increase in glycolysis, cancer cells transform their mitochondria into synthesis machines supported by augmented glutaminolysis, supplying lipid production, amino acid synthesis, and the pentose phosphate pathways. Inhibition of several of the key enzymes involved in these pathways has been demonstrated to effectively obstruct cancer cell growth and multiplication, sensitizing them to apoptosis. The modulation of various regulatory proteins involved in metabolic processes is central to cancerous reprogramming of metabolism. The finding that members of one of the major protein families involved in cell death regulation also aberrantly regulated in cancers, the Bcl-2 family of proteins, are also critical mediators of metabolic pathways, provides strong evidence for the importance of the metabolic shift to cancer cell survival. Targeting the anti-apoptotic members of the Bcl-2 family of proteins is proving to be a successful way to selectively target cancer cells and induce apoptosis. Further understanding of how cancer cells modify metabolic regulation to increase channeling of substrates into biosynthesis will allow for the discovery of novel drug targets to treat cancer. In the present review, we focused on the recent developments in therapeutic targeting of different steps in glycolysis, glutaminolysis and on the metabolic regulatory role of Bcl-2 family proteins.
近一个世纪前,奥托·瓦尔堡做出了一项开创性的观察:癌细胞与正常细胞不同,更喜欢一种看似低效的葡萄糖代谢机制——有氧糖酵解,这一现象现在被称为瓦尔堡效应。快速增殖的癌细胞倾向于葡萄糖的不完全代谢,产生大量乳酸而不是合成ATP来维持细胞生长,这一发现多年来一直困扰着科学家。对癌症代谢表型的进一步研究扩展了我们对这个令人困惑难题的理解,并为抗癌疗法的开发开辟了新途径。现在已知增强的糖酵解通量能增加中间体的合成,以维持对癌细胞生长至关重要的合成代谢途径。除了糖酵解增加外,癌细胞还将其线粒体转变为合成机器,这由增强的谷氨酰胺分解提供支持,为脂质生成、氨基酸合成和磷酸戊糖途径提供原料。已证明抑制这些途径中涉及的几种关键酶能有效阻碍癌细胞的生长和增殖,使它们对凋亡敏感。参与代谢过程的各种调节蛋白的调节是癌症代谢重编程的核心。参与细胞死亡调节的主要蛋白质家族之一的成员,即Bcl-2蛋白家族,在癌症中也异常调节,并且也是代谢途径的关键介质,这一发现为代谢转变对癌细胞存活的重要性提供了有力证据。事实证明,靶向Bcl-2蛋白家族的抗凋亡成员是选择性靶向癌细胞并诱导凋亡的成功方法。进一步了解癌细胞如何改变代谢调节以增加底物进入生物合成的通道,将有助于发现治疗癌症的新药物靶点。在本综述中,我们重点关注了糖酵解、谷氨酰胺分解不同步骤的治疗靶向的最新进展以及Bcl-2家族蛋白的代谢调节作用。