ABSTRACT
BACKGROUND/AIM: We aimed to investigate the synergistic effects of apigenin and curcumin on the cross-talk between apoptosis and autophagic cell death, as well as on paraptosis in HeLa cells. MATERIALS AND METHODS: Cell viability was measured using the MTT assay. Synergistic effects were measured using the Bliss independence model. qRT-PCR was used to study the expression of genes related to apoptosis, autophagic cell death, and cross-talk. GRP78/BiP immunostaining was used to identify endoplasmic reticulum (ER) stress. RESULTS: Treatment with a combination of apigenin and curcumin increased the expression levels of genes related to cell death in HeLa cells 1.29- to 27.6-fold. The combination of curcumin and apigenin showed a synergistic anti-tumor effect via cross-talk between processes leading to apoptosis and autophagic cell death, as well as ER stress-associated paraptosis. GRP78 expression was down-regulated, and massive cytoplasmic vacuolization was observed in HeLa cells. CONCLUSION: The combination of curcumin and apigenin is an effective potential therapeutic for cervical cancers.
Subject(s)
Apigenin/pharmacology , Apoptosis/drug effects , Autophagic Cell Death/drug effects , Curcumin/pharmacology , Adaptor Proteins, Signal Transducing/genetics , Caspase 3/physiology , Cell Survival/drug effects , Drug Synergism , Endoplasmic Reticulum Chaperone BiP , Female , HeLa Cells , Heat-Shock Proteins/analysis , Humans , Membrane Proteins/genetics , Proto-Oncogene Proteins/genetics , Uterine Cervical Neoplasms/drug therapyABSTRACT
BACKGROUND: The natural products have increasing important for the development of anticancer agents. Colchicum baytopiorum C.D. Brickell (C. baytopiorum), an endemic species for Turkey, contains colchicine and its derivatives. Stimulation of apoptotic and autophagy-mediated cell deaths are effective strategy for anticancer therapies. AIM: The aim of the study is to determine the role of the extract on both apoptotic and autophagic cell death in HeLa cell line. METHODS: The cell viability of C. baytopiorum (0.1 mg/ml) was determined by MTT assay. Active caspase-3 and t-Bid expressions were evaluated by immunohistochemical method. The mRNA expression of apoptotic regulatory genes (Bcl-xL, Bid, Bad, PUMA, NOXA, Caspase-3, -8, -9, Fas, FADD, TRADD, TRAF2, TNF, TNFR1), autophagic cell death related genes (Atg5-12, Beclin-1, DAPK), and also both autophagic and apoptotic cell death regulatory genes (Bif-1 and BNIP-3) were investigated by qRT-PCR. RESULTS: We determined that the expressions of both apoptotic and autophagic regulatory genes were significantly increased in the treatment group compared to control group. Also, we showed that C. baytopiorum crude extract induces the cross-connection between apoptotic and autophagic cell deaths in HeLa cells. CONCLUSION: We suggested that this endemic plant extract seems to be a new promising therapeutic approach in cancer.
