Fig. 4.

Lycorine hydrochloride affects the stability of MCL1 protein through FBXW7. a Quantitative PCR was performed to detect the mRNA level of MCL1 in gastric cancer cells after treatment with LH. b 293-FT cells were treated with LH (20 μM) or DMSO and were then treated with CHX (100 μg/mL) for the indicated times. Cell lysate was immunoblotted with the indicated antibodies. The density of MCL1 was measured, and the integrated optical density (IOD) was measured. The turnover of MCL1 was indicated graphically. c Cell lysate was prepared from 293-FT cells treated with DMSO or LH that had been treated with or without MG132 for 8 h. Equal amounts of cell lysate was immunoblotted with the indicated antibodies. d The ubiquitination of MCL1 in 293-FT cells was enhanced by treatment with LH. e Western blotting assays were performed to detect the expression of FBXW7 and MCL1 in MKN-45, SGC-7901 cells after treatment with LH. Tubulin was as internal reference. f Protein expression levels of MCL1 and FBXW7 were analyzed by western blotting in MKN-45, SGC-7901 cells. All data were analyzed by unpaired Student’s t-tests and were showed as the means ± SD. *p < 0.05, **p < 0.01, ***p < 0.001