In vitro antitumor activity of the ethyl acetate extract of Potentilla chinensis in osteosarcoma cancer cells
Authors: Hong-Xing Zhao
Jin-Gang Tao
Qiu-Dong Liang
Shen-Peng Liu
Guang Wan
Guo-Dong Wang
Journal: Molecular Medicine Reports (2016)
Discipline: CLINICAL MEDICINE
Keywords: anticancer effect; ethanol extract; Potentilla chinensis; MTT assay; cell viability
Affiliations: Department of Orthopedics, The First Affiliated Hospital of Xinxiang Medical University, Weihui, Henan 453100, P.R. China.

Abstract:  The aim of the current study was to evaluate the anticancer effect of the ethanol extract of Potentilla chinensis, a Chinese medicinal plant. An MTT assay was used to evaluate the cell viability of MG‑63 human osteosarcoma cancer cells and fR‑2 cells. Furthermore, the effect of the extract on apoptosis induction, cell cycle phase distribution and inhibition of cell migration in the MG63 human osteosarcoma cancer cell line was evaluated. The effect of the extract on cell cycle phase distribution was assessed by flow cytometry using propidium iodide (PI). Phase contrast microscopy detected the morphological changes in MG63 cancer cells following extract treatment. The results of the study demonstrated that the extract was cytotoxic to MG63 cancer cells, while the normal cell line (epithelial cell line) showed lower susceptibility. Phase contrast microscopy showed distinguishing morphological features, such as cell shrinkage and blebbing induced by the extract treatment in osteosarcoma cancer cells. The average proportion of Annexin V‑positive cells (total apoptotic cells) significantly increased from 5.6% in the control to 24.2, 38.8 and 55.7% in the 40, 80 and 150 µg/ml groups, respectively. The extract induced early and late apoptosis in the cancer cells. Flow cytometric analysis revealed that the extract induced G0/G1‑cell cycle arrest, which also showed significant dose‑dependence. The extract induced a significant and concentration‑dependent reduction in cell migration. Moreover, DNA fragmentation was also examined by observation of the formation of DNA ladders. It was demonstrated that DNA fragmentation was increased with extract concentration compared with that in the control. Taken together, EEPC may serve as potential therapeutic agent against osteosarcoma, provided that the toxicity profile and in vivo investigations demonstrate that it is safe. 

Retracted: Yes

PubPeer comments:
 *[left]* Figure 3 from [Wan et al (2016)] .  EEPC inhibited the growth of MG63 osteosarcoma cancer cells as shown by inverted light microscopy. Morphological changes of the cells after treatment with EEPC (magnification, x200). Cellular shrinkage was observed in EEPCu2011treated cells (arrows). MG63 cells were treated with (A) 0 u00b5g ml (control), (B) 40 u00b5g ml, (C) 80 u00b5g ml and (D) 150 u00b5g ml EEPC extract. The number of cells with shrinkage increased with an increase in the dose of the extract . *[right]* Figure 4 from [Liu et al (2016)] .  Morphological changes of the cells after treatment with 3-u03b2-erythrodiol (magnification x200) detected by phase contrast microscopy. Cellular shrinkage was observed in 3-u03b2-erythrodiol-treated cells (black arrows). (A) Control (untreated cells), (B-D) effect of 5, 50 and 100 u03bcM of 3-u03b2-erythrodiol on cell morphology of MKN-45 cells. The number of cells with shrinkage increased with the increasing dose of the compound. ![file] , 
 *[below]* Figure 7 from [Wan et al (2016)] .  Effect of EEPC extract on MGu201163 human osteosarcoma cancer cell migration in vitro. Images of wounds treated with (A) 0, (B) 40, (C) 80 and (D) 50 u00b5g ml EEPC extract for 48 h. The number of cells that migrated into the scratched area was calculated as a percentage of migration. *[above]* Fig. 5 from [Sui et al (2015)] .  Effect of rosamultic acid on human gastric cancer (SGC-7901) cell migration in vitro. Photographs of wound of cells treated with 0, 25, 50 and 100 u03bcM of rosamultic acid for 48 and 72 h. The number of cells migrated into the scratched area was calculated as a percentage of migration. ![file] , 
 Figure 6 from Wan et al (2016).  EEPC extract induces DNA fragmentation in MG-63 human osteosarcoma cancer cells. The cells were treated with 0, 40, 80 and 150 u00b5g ml of extract for 48 h. Cells from each sample were harvested for DNA gel electrophoresis as described. ![] For comparison: *[left]* Fig 11 from [Sui et al (2015)] .  Rosamultic acid induces DNA fragmentation in human gastric cancer cells (SGC-7901). The cells were treated with 0, 25, 50 and 100 u03bcM Rosamultic acid for 48 h. Cells from each sample were harvested for DNA gel electrophoresis as described in Materials and methods. *[right]* Figure 6 from [Gu et al (2015)] .  B.C extract induces DNA fragmentation in human epithelial ovarian cancer cells HO-8910. Cells were treated with 0, 20, 80 and 120 u03bcg ml of B.C extract for 48 hrs. Cells from each sample were harvested for DNA gel electrophoresis as described in Methods. The Figure shows the appearance of DNA fragments which increased with the increase of B.C extract concentration. No such fragments were seen in controls . ![] , 
 Retracted [5 May 2021] .  Following the publication of the above paper, a concerned reader drew to the Editor s attention that several figures bore striking similarities to other papers that were published at around the same time written by different authors based in different research institutions. Fig. 3 (in colour) was essentially the same as a greyscale figure (Fig. 4) in a paper published in* Oncology Reports*, which has now been retracted [Wan G, Tao Ju2011G, Wang Gu2011D, Liu Su2011P, Zhao Hu2011X and Liang Qu2011D: 3u2011u03b2u2011u0395rythrodiol isolated from Conyza canadensis inhibits MKNu201145 human gastric cancer cell proliferation by inducing apoptosis, cell cycle arrest, DNA fragmentation, ROS generation and reduces tumor weight and volume in mouse xenograft mode. Oncol Rep 35: 2328u20112338, 2016]. Furthermore, Figs. 5 and 6 in the above paper appeared to share data with Figs. 7 and 11, respectively, in a paper published in *Phytomedicine* [Sui Cu2011G, Meng Fu2011D and Jiang Yu2011h: Antiproliferative activity of rosamultic acid is associated with induction of apoptosis, cell cycle arrest, inhibition of cell migration and caspase activation in human gastric cancer (SGCu20117901) cells. *Phyomedicine* 22: 796u2011806, 2015]. After having conducted an independent investigation in the Editorial Office, the Editor of *Molecular Medicine Reports* has determined that the above paper should be retracted from the Journal on account of a lack of confidence concerning the originality and the authenticity of the data. The authors were asked for an explanation to account for these concerns, but the Editorial Office never received any reply. The Editor regrets any inconvenience that has been caused to the readership of the Journal. ,