Apoptotic Effects and Cell Cycle Arrest Effects of Extracts from Cnidium monnieri (L.) Cusson through Regulating Akt/mTOR/GSK-3β Signaling Pathways in HCT116 Colon Cancer Cells

Abstract

The Cnidium monnieri (L.) Cusson is an annual plant distributed in China and Korea. The fruit of C. monnieri is used as a medicinal herb that is effective for the treatment of carbuncle and pain in female genitalia. However, the anti-cancer effects of CME have not yet been reported. In this study, we assessed the apoptotic effects and cell cycle arrest effects of ethanol extracts from C. monnieri on HCT116 colon cancer cells. The results of an MTT assay and LDH assay demonstrated a decrease in cell viability and the cytotoxic effects of CME. In addition, the number of apoptotic body and the apoptotic rate were increased in a dose-dependent manner through Hoechst 33342 staining and Annexin V-PI double staining. In addition, cell cycle arrest occurred at the G1 phase by CME. Protein kinase B (Akt) plays an important role in cancer cell survival, growth, and division. Akt down-regulates apoptosis-mediated proteins, such as mammalian target of rapamycin (mTOR), p53, and Glycogen Synthase kinase-3β (GSK-3β). CME could regulate the expression levels of p-Akt, p-mTOR, p-GSK-3β, Bcl-2 family members, caspase-3, and PARP. Furthermore, treatment with CME, LY294002 (PI3K/Akt inhibitor), BIO (GSK-3β inhibitor), and Rapamycin (mTOR inhibitor) showed that apoptotic effects occurred through the regulation of the AKT/mTOR/GSK-3β signaling pathway. Our results demonstrated CME could induce apoptosis and cell cycle arrest in HCT116 colon cancer cells.Key words : AKT/mTOR/GSK-3β pathway, apoptosis, cell cycle arrest, CME, HCT116 *Corresponding author *Tel : +82-42-629-8760 , Fax : +82-42-629-8873 *E-mail : kym@hnu.kr This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Extracts from Cnidium monnieri (L.) Cusson Induces Apoptosis and G1 Cell Cycle Arrest through Reducing COX-2 Expression by Regulating the Akt/GSK-3β Signaling Pathways

“…1(d). These results indicated that CME treatment induces anti-proliferative, cytotoxic, and cell morphological changes in HT-29 colon cancer cells also like other studies [26][27][35][36][37][38]. Western blot analysis of Bcl-2, Bak, Cytochrome c, COX-IV, and β-actin in cytosolic and mitochondrial fractions of HT-29 cells treated with CME (40~80 μg/mL) for 24 h. The β-actin probe served as protein-loading control in cytosol.…”

“…Many previous studies reported that natural plant extracts suppress cell proliferation in colon cancer cells [35][36][37][38]. Moreover, the treatments of CME did not show cytotoxicity in normal cells such as Fibroblast and HaCaT cells [26,27]. We examined the anti-proliferative and cytotoxic effects of CME using the MTT assay and LDH release assay.…”

“…The bioactive components of Cnidium monnieri (L.) Cusson is coumarins, which includes osthole, xanthotoxin, isopimpinellin, bergapten, and imperatorin. Osthole, is one of the major coumarin compounds with various pharmacological functions, such as anti-cancer effects [24,25].The anti-cancer effects of CME were determined in various cell lines [26][27][28]. However, research on the HT-29 cells is insufficient yet.…”