Arenobufagin activates p53 to trigger esophageal squamous cell carcinoma cell apoptosis in vitro and in vivo

Abstract

Esophageal squamous cell carcinoma (ESCC) is often diagnosed at late incurable stage and lacks effective treatment strategy. Bufadienolides are cardiotonic steroids isolated from the skin and parotid venom glands of the toad Bufo bufo gargarizans Cantor with novel anticancer activity. However, there is little information about the effects and action mechanisms of bufadienolides on ESCC cells. In this study, the in vitro and in vivo anti-ESCC activities of bufadienolides, including bufalin (Bu) and arenobufagin (ArBu), were examined and the underlying molecular mechanisms were elucidated. The results showed that ArBu exhibited higher anticancer efficacy than Bu against a panel of five ESCC cells, with IC50 values ranging from 0.8 μM to 3.6 μM. However, ArBu showed lower toxicity toward Het-1A human normal esophageal squamous cells, indicating its great selectivity between cancer and normal cells. Moreover, ArBu effectively induced ESCC cell apoptosis mainly by triggering caspase activation through intrinsic and extrinsic pathways. Treatment of ESCC cells also significantly activated p53 signaling by enhancing its phosphorylation. Interestingly, transfection of cells with p53 small interfering RNA significantly inhibited the ArBu-induced p53 phosphorylation and the overall apoptotic cell death. Furthermore, ArBu also demonstrated novel in vivo anticancer efficacy by inhibiting the tumor growth through activation of p53 pathway. Taken together, these results demonstrate the p53-targeting therapeutic potential of bufadienolides against ESCC.

Network Pharmacology Study on the Pharmacological Mechanism of Cinobufotalin Injection against Lung Cancer

“…e researchers established a nude mouse model with xenograft transplantation of A549 tumor and confirmed that cinobufotalin inhibits tumor growth through regulation of the nonapoptotic death pathway of cyclophilin-D in lung cancer cells [27,28]. Arenobufagin, a cardiac glycoside extracted from toad skin, activates caspase-mediated apoptosis of esophageal cancer cells through exogenous and endogenous pathways [29]. e authors of this previous study have also confirmed that arenobufagin exerts good antivascular effect and blocks the migration and invasion of human umbilical vein endothelial cells by inhibiting the expression of VEGF [30].…”

Time series expression pattern of key genes reveals the molecular process of esophageal cancer

“…Cellular proliferation and cell cycle are regulated by regulating MDM2/P53 signaling in esophageal squamous cell carcinoma [34]. In the study of isoleucine anti-esophageal squamous cell carcinoma, it was found that iso-valine can inhibit tumor growth by activating the p53 pathway [35]. Zuev et al [36] studied the insulin levels and islet β-cell morphology changes in 27 patients with esophageal cancer after one-stage esophagectomy and gastric pedicle graft repair.…”

Arenobufagin Induces Apoptotic Cell Death in Human Non-Small-Cell Lung Cancer Cells via the Noxa-Related Pathway

“…Toad venom has been widely used in China as a local anesthetic, cardiotonic, antimicrobial, and antineoplastic agent for many years [ 26 , 27 ]. Arenobufagin, as one of the main biologically active compounds extracted from toad venom, has been showed to exhibit potential anti-cancer effects in human hepatocellular carcinoma (HCC), esophageal squamous cell carcinoma and cervical carcinoma cells [ 19 , 21 , 22 ]. However, the anti-NSCLC effects of arenobufagin are largely unknown.…”

“…Deng et al found that arenobufagin could intercalate with DNA to induce G2 cell cycle arrest through the ATM/ATR pathway in HCC cells [ 20 ]. Except in HCC, arenobufagin has also been shown to inhibit growth and induce apoptosis in human esophageal squamous cell carcinoma cells and cervical carcinoma cells [ 21 , 22 ]. However, the effects and mechanisms of arenobufagin on lung cancer are still not clear.…”