title: Screening of potential chemical carcinogens by means of mammalian cells in vitro.
abstract: A survey is presented about the current state of the efforts to the development of rapid screening systems for carcinogenic substances by means of mammalian cells in vitro. At present two fundamental ways for the realization of this task seem possible: a) So-called host-mediated assays which are a combination of carcinogen application into intact animals (possibly pregnant animals) and succeeding explantation of organs from these animals or establishment of cell cultures from fetuses following transplacental action of the compound tested. In this type of experiment the metabolization of the compound is accomplished within the organism and the critical problem of metabolic competence of cultured cells is bypassed. b) Direct application of the carcinogen into cell cultures. Beside the hitherto most used fresh embryonic cells there is an increasing tendency to use established cell lines with a rigid post-confluence inhibition of proliferation and an extremely low background of spontaneous alteration in vitro. Possibilities for the metabolic activation in this system are pointed out. The value of "indicators" of carcinogen-induced alterations in relation to neoplastic properties is discussed. Most of the higherto existing test systems are problematic in their relevancy, but the findings published in literature indicate that cell cultures offer a very promissing possibility for the early detection of carcinogenic agents in human environment.
mesh_terms: D015127:9,10-Dimethyl-1,2-benzanthracene / Q000009:adverse effects; D000818:Animals; D002273:Carcinogens / Q000032:analysis*; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D006224:Cricetinae; D003634:DDT / Q000009:adverse effects; D004052:Diethylnitrosamine / Q000009:adverse effects; D004128:Dimethylnitrosamine / Q000009:adverse effects; D004353:Drug Evaluation, Preclinical; D005038:Ethylnitrosourea / Q000009:adverse effects; D005260:Female; D006168:Guinea Pigs; D066298:In Vitro Techniques; D008770:Methylnitrosourea / Q000009:adverse effects; D051379:Mice; D009374:Neoplasms, Experimental / Q000139:chemically induced* / Q000378:metabolism; D011247:Pregnancy; D051381:Rats
chemical_list: D002273:Carcinogens; D004052:Diethylnitrosamine; D015127:9,10-Dimethyl-1,2-benzanthracene; D008770:Methylnitrosourea; D003634:DDT; D004128:Dimethylnitrosamine; D005038:Ethylnitrosourea