[Cell culture and its application--in vitro evaluation of anticancer activity using human tumor cell lines].

Selective toxicity against cancer cells is a most important determinant for anticancer agents. Therefore, we have preferably evaluated anticancer effects in vivo using murine tumor models for several decades. Approximately 50 anticancer agents are currently available for clinical therapy, but very few agents are effective against some types of cancer. Much progresses in cell culture techniques resulted in establishment of various human tumor cell lines. Currently, we are able to use human tumor lines as well as murine ones for the examination of drug sensitivity. A number of assay methods to evaluate anticancer activity have been developed. In the beginning, growth inhibitory activity was evaluated by counting cell numbers after drug exposure. Then, human tumor clonogenic assay (HTCA) was designed to measure only proliferative cells. Recently colorimetric MTT assay and SRB assay in 96-well microplates were developed, which were adopted in the screening system in the NCI, based on a new idea, that is, disease-oriented screening (DOS) using about 60 human tumor cell lines. In this paper outline of each method was described, adding especially several comments on disease-oriented screening.