Polyamines are necessary for the survival of human small-cell lung carcinoma in culture.

Publisher Website
Google Scholar
Abstract
Many human small-cell lung carcinoma culture lines grow as multicellular aggregate spheroids, for which high L-dopa decarboxylase activity is a marker. During the initial cell aggregation and the exponential growth phase, there is a marked increase in ornithine decarboxylase activity and an accumulation of polyamines. .alpha.-Difluoromethylornithine, a specific enzyme-activated, irreversible ornithine decarboxylase inhibitor, blocks the increase in ornithine decarboxylase activity and in polyamines and inhibits human small-cell lung carcinoma cell growth. After the onset of a decreased proliferation rate, the multicellular spheroid aggregates become poorly formed, cell loss ensues and there is a decrease in L-dopa decarboxylase activity. Ornithine decarboxylase and the polyamines apparently play an essential role not only in the proliferative phase but also in the viability of human small-cell lung carcinoma cells in culture. .alpha.-Difluoromethylornithine, a virtually nontoxic compound, may be potentially useful in the therapy of this human tumor.