In vitro transformation assays not only serve practical purposes in screening for potential carcinogenic substances in food, drug, and cosmetic industries, but more importantly, they provide a means of understanding the critical biological processes behind in vivo cancer development. In resemblance to cancer cells in vivo, successfully transformed cells display loss of contact inhibition, gain of anchorage independent growth, resistant to proper cell cycle regulation such as apoptosis, faster proliferation rate, potential for cellular invasion, and ability to form tumors in experimental animals. Cells purposely transformed using metal exposures enable researchers to examine molecular changes, dissect various stages of tumor formation, and ultimately elucidate metal induced cancer mode of action. For practical purposes, this review specifically focuses on studies incorporating As-, Cd-, Cr-, and Ni-induced cell transformation. Through investigating and comparing an extensive list of studies using various methods of metal-induced transformation, this review serves to bridge an information gap and provide a guide for avoiding procedural discrepancies as well as maximizing experimental efficiency.

中文翻译：

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金属诱导的细胞转化研究的全面综述。

体外转化测定不仅可用于筛选食品，药品和化妆品行业中潜在致癌物质的实际目的，而且更重要的是，它们提供了一种了解体内癌症发展背后的关键生物学过程的手段。与体内癌细胞相似，成功转化的细胞表现出失去接触抑制，不依赖锚定生长，对适当的细胞周期调节（例如凋亡），更快的增殖速率，细胞入侵的潜力以及在实验动物中形成肿瘤的能力具有抵抗力。研究人员使用金属暴露对细胞进行了有目的的转化，使研究人员能够检查分子的变化，解剖肿瘤形成的各个阶段，并最终阐明金属诱导的癌症的作用方式。出于实际目的，这篇评论特别侧重于结合As，Cd，Cr和Ni诱导的细胞转化的研究。通过调查和比较使用各种金属诱导的转化方法的广泛研究清单，本综述有助于弥合信息鸿沟，并为避免程序差异以及最大程度地提高实验效率提供了指导。