[Preparation of tumor cells from human lung cancer tissue for the purpose of cloning].

Various approaches to isolation of tumor cells are analyzed on the basis of examination of 46 human pulmonary tumors of different histologic types. Mechanical treatment alone resulted in the death of the majority of tumor cells. Short trypsin treatment (for 10-15 min in several stages) proved to be the most suitable for disaggregation of small-cell carcinoma, adenocarcinoma, and carcinoid samples. A specific approach has been developed for isolation of cells from squamous-cell carcinoma, consisting in tumor treatment with 0.25 percent trypsin at 4 degrees C for 16-18 h, followed by DNAase, collagenase, and trypsin treatment, and then again trypsin treatment at 37 degrees C for 10-15 min. The suggested approaches permit a harvest of at least 6 x 10(6) tumor cells from 1 g of tissue, with more than 70 percent of these cells viable.