Induction of flat morphology in K-ras-transformed fibroblasts by lycorine, an alkaloid isolated from the tropical plant Eucharis grandiflora.

In the course of screening for Ras function inhibitors from plant extracts, we isolated lycorine from a chloroform extract of Eucharis grandiflora leaves. Lycorine induced flat morphology in K-ras-NRK cells after treatment for 2-3 days, whereas its morphological effect on NRK cells was weaker. Lycorine was found to inhibit protein synthesis specifically in cultured K-ras-NRK cells. It also lowered the cellular amount of Ras in 2-3 days.