Combination of Withaferin-A and CAPE Provides Superior Anticancer Potency: Bioinformatics and Experimental Evidence to Their Molecular Targets and Mechanism of Action.

Anissa Nofita Sari,Keiji Terao,Seyad Shefrin,Renu Wadhwa,Durai Sundar,Yoshiyuki Ishida,Navaneethan Radhakrishnan,Priyanshu Bhargava,Jayarani F Putri,Sunil C Kaul,Jaspreet Kaur Dhanjal

doi:10.3390/cancers12051160

Abstract

We have earlier reported anticancer activity in Withaferin A (Wi-A), a withanolide derived from Ashwagandha (Withania somnifera) and caffeic acid phenethyl ester (CAPE), an active compound from New Zealand honeybee propolis. Whereas Wi-A was cytotoxic to both cancer and normal cells, CAPE has been shown to cause selective death of cancer cells. In the present study, we investigated the efficacy of Wi-A, CAPE, and their combination to ovarian and cervical cancer cells. Both Wi-A and CAPE were seen to activate tumor suppressor protein p53 by downregulation of mortalin and abrogation of its interactions with p53. Downregulation of mortalin translated to compromised mitochondria integrity and function that affected poly ADP-ribose polymerase1 (PARP1); a key regulator of DNA repair and protein-target for Olaparib, drugs clinically used for treatment of breast, ovarian and cervical cancers)-mediated DNA repair yielding growth arrest or apoptosis. Furthermore, we also compared the docking capability of Wi-A and CAPE to PARP1 and found that both of these could bind to the catalytic domain of PARP1, similar to Olaparib. We provide experimental evidences that (i) Wi-A and CAPE cause inactivation of PARP1-mediated DNA repair leading to accumulation of DNA damage and activation of apoptosis signaling by multiple ways, and (ii) a combination of Wi-A and CAPE offers selective toxicity and better potency to cancer cells.

Highlights

Withaferin A (Wi-A) is a steroidal lactone found in Withania somnifera (Ashwagandha), a popular ayurvedic herb
Several earlier studies have reported that the cytotoxicity of Wi-A and caffeic acid phenethyl ester (CAPE) to cancer cells is mediated, at least in part, by targeting mortalin-p53 interactions [7,9,10,20] and reactivation of wild type p53 activities
We investigated if reduction in mortalin and PARP1 in Wi-A/CAPE-treated cells was interlinked

Summary

Introduction

Withaferin A (Wi-A) is a steroidal lactone found in Withania somnifera (Ashwagandha), a popular ayurvedic herb. Cancers 2020, 12, 1160 of its action have been described that include (i) induction of oxidative stress, reactive oxygen species (ROS) generation and loss of mitochondrial membrane potential yielding caspases and poly ADP-ribose polymerase (PARP) cleavage mediated apoptosis; (ii) inhibition of NF-kappa B signaling; (iii) targeting of Vimentin intermediate filaments, an essential protein involved in adhesion, migration, survival, and epithelial-mesenchymal transition (EMT); (iv) inhibition of AKT signaling;. Apoptosis and differentiation are the two common endpoints reported for CAPE-treated cancer cells [24,25,26,27,28,29]. Multiple mechanisms of its action demonstrated in several laboratory studies, so far, include (i) inhibition of NF-kappa B and nitric oxide synthase (iNOS) signaling [26,32,33];

Methods

Results

Conclusion