Costa M
Nelson Institute of Environmental Medicine, New York University Medical Center, New York 10016.
Scand J Work Environ Health. 1993;19 Suppl 1:71-4.
Water-insoluble nickel compounds tend to be carcinogenic because they enter cells through phagocytosis. Highly water-soluble nickel salts, such as nickel chloride, do not enter cells well and thus are not carcinogenic in vivo. Carcinogenic nickel compounds produce selective damage to heterochromatic regions in Chinese hamster chromosomes, probably because of the high concentration of proteins and amino acids in this highly condensed genetically inactive chromatin region. Bivalent nickel ions are highly affinitive to amino acids as compared with deoxyribonucleic acid (DNA). The interaction with proteins is believed to cause this effect. In addition, when nickel binds to proteins, it can be oxidized, and DNA protein damage ensues. A new method detects DNA-protein cross-links induced by various agents, such as nickel, chromium and cis-platinum. It has demonstrated an increase in DNA-protein cross-links in cultured cells from animals treated with chromate and welders exposed to welding fumes.
水不溶性镍化合物往往具有致癌性，因为它们通过吞噬作用进入细胞。高度水溶性的镍盐，如氯化镍，不易进入细胞，因此在体内不具有致癌性。致癌性镍化合物对中国仓鼠染色体的异染色质区域产生选择性损伤，这可能是因为在这个高度浓缩的遗传惰性染色质区域中蛋白质和氨基酸浓度很高。与脱氧核糖核酸（DNA）相比，二价镍离子对氨基酸具有高度亲和力。据信与蛋白质的相互作用会导致这种效应。此外，当镍与蛋白质结合时，它会被氧化，进而导致DNA蛋白质损伤。一种新方法可检测由各种试剂（如镍、铬和顺铂）诱导的DNA-蛋白质交联。该方法已证明，在用铬酸盐处理的动物的培养细胞以及接触焊接烟雾的焊工的细胞中，DNA-蛋白质交联有所增加。
