Genistein induces G2/M cell cycle arrest and apoptosis via ATM/p53-dependent pathway in human colon cancer cells
نویسندگان
چکیده
Soybean isoflavones have been used as a potential preventive agent in anticancer research for many years. Genistein is one of the most active flavonoids in soybeans. Accumulating evidence suggests that genistein alters a variety of biological processes in estrogen-related malignancies, such as breast and prostate cancers. However, the molecular mechanism of genistein in the prevention of human colon cancer remains unclear. Here we attempted to elucidate the anticarcinogenic mechanism of genistein in human colon cancer cells. First we evaluated the growth inhibitory effect of genistein and two other isoflavones, daidzein and biochanin A, on HCT-116 and SW-480 human colon cancer cells. In addition, flow cyto-metry was performed to observe the morphological changes in HCT-116/SW-480 cells undergoing apoptosis or cell cycle arrest, which had been visualized using Annexin V-FITC and/or propidium iodide staining. Real-time PCR and western blot analyses were also employed to study the changes in expression of several important genes associated with cell cycle regulation. Our data showed that genistein, daidzein and biochanin A exhibited growth inhibitory effects on HCT-116/SW-480 colon cancer cells and promoted apoptosis. Genistein showed a significantly greater effect than the other two compounds, in a time- and dose-dependent manner. In addition, genistein caused cell cycle arrest in the G2/M phase, which was accompanied by activation of ATM/p53, p21waf1/cip1 and GADD45α as well as downregulation of cdc2 and cdc25A demonstrated by q-PCR and immunoblotting assay. Interestingly, genistein induced G2/M cell cycle arrest in a p53-dependent manner. These findings exemplify that isoflavones, especially genistein, could promote colon cancer cell growth inhibition and facilitate apoptosis and cell cycle arrest in the G2/M phase. The ATM/p53-p21 cross-regulatory network may play a crucial role in mediating the anticarcinogenic activities of genistein in colon cancer.
منابع مشابه
Genistein Induces Apoptosis and Inhibits Proliferation of HT29 Colon Cancer Cells
Soybean isoflavone genistein has multiple anticancer properties and its pro-apoptotic and anti-proliferative effects have been studied in different cancer cells. However, the mechanisms of action of genistein and its molecular targets on human colon cells have not been fully elucidated. Therefore, caspase-3 and p38 mitogen-activated protein kinase (p38 MAPK) as the main therapeutic targets...
متن کاملSterigmatocystin-Induced DNA Damage Triggers G2 Arrest via an ATM/p53-Related Pathway in Human Gastric Epithelium GES-1 Cells In Vitro
Sterigmatocystin (ST), which is commonly detected in food and feed commodities, is a mutagenic and carcinogenic mycotoxin that has been recognized as a possible human carcinogen. Our previous study showed that ST can induce G2 phase arrest in GES-1 cells in vitro and that the MAPK and PI3K signaling pathways are involved in the ST-induced G2 arrest. It is now widely accepted that DNA damage pla...
متن کاملThe histone deacetylase inhibitor trichostatin A induces cell cycle arrest and apoptosis in colorectal cancer cells via p53-dependent and -independent pathways.
Many chemotherapeutic agents induce apoptosis via a p53-dependent pathway. However, up to 50% of human cancers have p53 mutation and loss of p53 function. Histone deacetylase inhibitors (HDACIs) are emerging as a potentially important new class of anticancer agents. Here, we report that, Trichostatin A (TSA), a pan-HDAC inhibitor, could induce G2/...
متن کاملSynergistic Anti-Cancer Effects of Second-Generation Proteasome Inhibitor Carfilzomib with Doxorubicin and Dexamethasone Via p53-Mediated Apoptosis in Pre-B Acute Lymphoblastic Leukemia Cells
Background: The ubiquitin-proteasome system (UPS) plays a crucial role in regulating the levels and functions of a large number of proteins in the cell, which are important for cancer cell growth and survival. The proteasome is highly activated in B-cell precursor acute lymphoblastic leukemia (BCP-ALL), which is the most common malignancy in children. The attempt to inhibit proteasome as a ther...
متن کاملGenistein enhances the radiosensitivity of breast cancer cells via G₂/M cell cycle arrest and apoptosis.
The aim of the present study was to investigate the radiosensitizing effect of genistein, and the corresponding mechanisms of action on breast cancer cells with different estrogen receptor (ER) status. Human breast cancer cell lines such as MCF-7 (ER-positive, harboring wild-type p53) and MDA-MB-231 (ER-negative, harboring mutant p53) were irradiated with X-rays in the presence or absence of ge...
متن کامل