A Combined Phytochemistry and Network Pharmacology Approach to Reveal the Potential Antitumor Effective Substances and Mechanism of Phellinus igniarius.

Yu Dong,Kequn Chai,Lisha Zhao,Yiqi Wang,Ping Qiu,Dan Shou,Rui Zhu,Huajun Zhao,Pinghu Zhang,Changyu Li

doi:10.3389/fphar.2019.00266

Abstract

Phellinus igniarius (P. igniarius) is a medicinal fungus that is widely used in East Asia for the adjuvant treatment of cancer. To elucidate the antitumor effective substances and mechanism of P. igniarius, we designed an approach incorporating cytotoxicity screening, phytochemical analysis, network pharmacology construction, and cellular and molecular experiments. The dichloromethane extract of P. igniarius (DCMPI) was identified as the active portion in HT-29 cells. Nineteen constituents were identified, and 5 were quantified by UPLC-ESI-Q/TOF-MS. Eight ingredients were obtained in the network pharmacology study. In total, 473 putative targets associated with DCMPI and 350 putative targets related to colon cancer were derived from online databases and target prediction tools. Protein-protein interaction networks of drug and disease putative targets were constructed, and 84 candidate targets were identified based on topological features. Pathway enrichment analysis showed that the candidate targets were mostly related to reactive oxygen species (ROS) metabolic processes and intrinsic apoptotic pathways. Then, a cellular experiment was used to validate the drug-target mechanisms predicted by the system pharmacology analysis. Experimental results showed that DCMPI increased intracellular ROS levels and induced HT-29 cell apoptosis. Molecular biology experiments indicated that DCMPI not only increased Bax and Bad protein expression and promoted PARP and caspase-3/9 cleavage but also down-regulated Bcl-2 and Bcl-xl protein levels to induce apoptosis in HT-29 cells. In conclusion, our study provides knowledge on the chemical composition and antitumor mechanism of P. igniarius, which may be exploited as a promising therapeutic option for colon cancer.

Highlights

Cancer serves as a major public health problem worldwide and is expected to surpass heart disease as the leading cause of death in the few years (Siegel et al, 2016)
Normal HT-29 cells appeared whole, healthy, and polygonal in shape under a microscope; after administering dichloromethane extract of P. igniarius (DCMPI), the HT-29 cells exhibited a number of morphological alterations, including cell shrinkage, condensed chromatin, membrane blebbing, and an increased density of apoptotic cells (Figure 1B)
The chemical profiles of DCMPI were analyzed by UPLCESI-Q/TOF-mass spectrometer (MS)

Summary

Introduction

Cancer serves as a major public health problem worldwide and is expected to surpass heart disease as the leading cause of death in the few years (Siegel et al, 2016). Numerous significant advances in cancer research have revealed the genetics and pathologies of malignant tumors, which, in turn, facilitates the development of novel anticancer agents (Hare et al, 2017). Multiple bioactive phytochemicals in consumed edible and medicinal fungi have recently attracted considerable attention as potential candidates for anticancer agents (Li et al, 2015). Recent studies have creatively focused on the potential functions of P. igniarius extracts and their constituent compounds in the prevention and treatment of cancer (Zhou et al, 2014; Sangdee et al, 2017). No prior system reports on the chemical composition of P. igniarius contribute to its antitumor activity or functional mechanisms

Methods

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Discussion

Conclusion