Theocharis S E, Margeli A P, Koutselinis A
Department of Forensic Medicine and Toxicology, Medical School, University of Athens, Greece.
Int J Biol Markers. 2003 Jul-Sep;18(3):162-9. doi: 10.1177/172460080301800302.
The metallothionein (MT) family is a class of low molecular weight, intracellular and cysteine-rich proteins presenting high affinity for metal ions. Although the members of this family were discovered nearly 40 years ago, their functional significance remains obscure. Four major MT isoforms, MT-1, MT-2, MT-3 and MT-4, have been identified in mammals. MTs are involved in many pathophysiological processes such as metal ion homeostasis and detoxification, protection against oxidative damage, cell proliferation and apoptosis, chemoresistance and radiotherapy resistance. MT isoforms have been shown to be involved in several aspects of the carcinogenic process, cancer development and progression. MT expression has been implicated as a transient response to any form of stress or injury providing cytoprotective action. Although MT participates in the carcinogenic process, its use as a potential marker of tumor differentiation or cell proliferation, or as a predictor of poor prognosis remains unclear. In the present review the involvement of MT in defense mechanisms to toxicity and in carcinogenicity is discussed.
金属硫蛋白（MT）家族是一类低分子量、细胞内且富含半胱氨酸的蛋白质，对金属离子具有高亲和力。尽管该家族成员在近40年前就已被发现，但其功能意义仍不明确。在哺乳动物中已鉴定出四种主要的MT亚型，即MT-1、MT-2、MT-3和MT-4。MT参与许多病理生理过程，如金属离子稳态和解毒、抗氧化损伤保护、细胞增殖和凋亡、化疗耐药和放疗耐药。MT亚型已被证明参与致癌过程、癌症发展和进展的多个方面。MT表达被认为是对任何形式的应激或损伤的一种瞬时反应，具有细胞保护作用。尽管MT参与致癌过程，但其作为肿瘤分化或细胞增殖的潜在标志物，或作为预后不良的预测指标仍不明确。在本综述中，讨论了MT在毒性防御机制和致癌性中的作用。
