Anticancer Action of Psilostachyin-A in 5-Fluorouracil-Resistant Human Liver Carcinoma are Mediated Through Autophagy Induction, G2/M Phase Cell Cycle Arrest and Inhibiting Extracellular-Signal-Regulated Kinase/Mitogen Activated Protein Kinase (ERK/MAPK) Signaling Pathway
Authors: Lei Huang
Xiangang Xu
Jun Liu
Yan Liu
Jun Wang
Guoliang Wang
Chengxian Shi
Jianzhao Huang
Journal: Medical Science Monitor (2019)
Discipline: CLINICAL MEDICINE
Keywords: Liver cancer; Psilostachyin-A; Anticancer effect; Autophagy; Cell cycle
Affiliations: Department of Hepatobiliary Surgery, Guizhou Provincial People’s Hospital, Guiyang, Guizhou, China (mainland)

Abstract:  BACKGROUND Liver cancer is one of the most common malignancies around the world and one of the major causes of cancer related mortality. The objective of this study was to evaluate the anticancer effect of the natural compound psilostachyin-A on 5-fluorouracil-resistant human liver carcinoma cells and its effects on autophagy, cell cycle, caspase activation, and the ERK/MAPK signaling pathway. MATERIAL AND METHODS Cell Counting Kit 8 (CCK-8) assay was used to evaluate the effects on HepG2 cell viability at different doses of psilostachyin-A. Cell cycle analysis was performed using flow cytometry, and Transwell assay was used to check effects on cell invasion. Transmission electron microscopic studies were done to evaluate autophagy induced by psilostachyin-A, and the western blot method was carried out to evaluate the effects on autophagy and the ERK/MAPK signaling pathway. RESULTS CCK-8 assay revealed that the psilostachyin-A reduced the cell viability of HepG2 cancer cells in a dose dependent manner. Psilostachyin-A also reduced the colony forming potential of HepG2 cells, concentration dependently. The IC50 of psilostachyin was found to be 25 µM. The anticancer effects of psilostachyin-A were due to the induction of autophagy which was accompanied by enhancement of LC3B II expression. Psilostachyin also caused cell cycle arrest by enhancing the accumulation of HepG2 cells in the G2/M phase. Transwell assay showed that psilostachyin-A suppressed the invasion of HepG2 cells. The results also showed that psilostachyin-A could block the ERK/MAPK pathway, indicative of the cytotoxic effects of psilostachyin-A on liver cancer. CONCLUSIONS These preliminary observations suggested that psilostachyin-A might prove beneficial in the treatment of liver cancer. 

Retracted: Yes

PubPeer comments:
 Figure 3.  Psilostachyin-A induces autophagy in the HepG2 cells as indicated by electron microscopy. ... Psilostachyin-A led to the formation of autophagosomes in a dose-dependent manner . ![file] For comparison. *[left]* Figure 6 from [Ding et al (2019)] .  Induction of autophagy in COLO-205 human colon cancer cells as indicated by Transmission electron microscopy (TEM) at different concentrations of angustifoline drug . *[right]* Figure 4 from [Li et al (2019)] .  Electron microscopy shows the effects of parthenolide on the development of autophagosomes in MDA-T32 human papillary thyroid carcinoma cells. The arrows indicate autophagosomes . ![] Another sighting! Fig 5 from [Ma et al (2019)] . ![] , 
 *[left]* Figure 2 from [Liu et al (2020)] .  Effect of on the colony formation of the psilostachyin-A treated HepG2 cells as determined by microscopy. ... Psilostachyin-A decreased cancer colony formation dose-dependently. *[right]* Figure 2 from [Xu et al (2019)] .  Colony formation assay showing the colon formation in miR-NC and miR-181 mimics transfected U87 and U118 cells. ![file] , 
 Retracted [25 March 2021] .  An editorial decision has been made to retract this manuscript due to breach of publishing guidelines, following the identification of non-original and manipulated figures. ,