SAV1 and lung cancer: Furthermore, co-immunoprecipitation (Co-IP) and western blotting showed that levels of ubiquitinated SAV1 protein were markedly lower in lycorine-treated SPC-A-1 cells than in cells without lycorine treatment (Fig. 3g, h), suggesting that lycorine-induced SAV1 protein accumulation in lung cancer cells is mediated by inhibiting the ubiquitination–proteasome system that degrades SAV1.