Endoplasmic reticulum stress triggered by Soyasapogenol B promotes apoptosis and autophagy in colorectal cancer

Publication date: Available online 14 December 2018Source: Life SciencesAuthor(s): Luping Wang, Lu Yun, Xiaojun Wang, Liying Sha, Luning Wang, Yingying Sui, Hui ZhangAbstractAimColorectal cancer (CRC) is a common human malignancy which accounts for 600,000 deaths annually at the global level. Soyasapogenol B (Soy B), an ingredient of soybean, has been found to exert anti-proliferative activities in vitro in human breast cancer cells. The current study aimed to evaluate the efficacy of Soy B in suppressing CRC.Methods and materialsThe effect of Soy B on cell viability was assessed using the Cell Counting Kit-8 (CCK-8) assay. The effect of Soy B on cell proliferation was determined using colony formation assay. The percentage of apoptotic cells was determined by the TUNEL assay and flow cytometry following Annexin V-FITC/Propidium Iodide (PI) double staining. JC-1 staining was performed to examine the change in mitochondrial membrane potential. Autophagy was examined by acridine orange staining and mRFP-GFP-LC3 adenovirus transfection. Caspase-12 activities were determined by ELISA kit. Western blotting was used to determine the expression of relevant proteins. To investigate the role of autophagy in the pro-death and pro-apoptotic activities of Soy B, autophagy inhibitors Bafilomycin A1 (Baf-A1) and Atg5 siRNA were utilized. TUDCA and CHOP shRNA were utilized to block ER stress. Moreover, a CRC xenograft murine model was used to analyze the therapeutic efficacy of Soy B in viv...
Source: Life Sciences - Category: Biology Source Type: research