Silencing of COL1A2, COL6A3, and THBS2 inhibits gastric cancer cell proliferation, migration, and invasion while promoting apoptosis through the PI3k‐Akt signaling pathway
Authors: Ran Ao
Jia-Ni Wang
Lin Guan
Ying Wang
Journal: Journal of Cellular Biochemistry (2018)
Discipline: MOLECULAR BIOLOGY & GENETICS
Keywords: COL1A2; COL6A3; PI3K-Akt signaling pathway; THBS2; apoptosis
Affiliations: Department of Gastroenterology, The First Affiliated Hospital of China Medical University, Shenyang, P.R. China.

Abstract:  This study explores the effect of COL1A2, COL6A3, and THBS2 gene silencing on proliferation, migration, invasion, and apoptosis of gastric cancer cells through the PI3K-Akt signaling pathway. The gastric cancer microarray expression data (GSE19826, GSE79973, and GSE65801) was analyzed. Gastric cancer tissues and corresponding adjacent normal tissues were extracted from patients. Positive expression rate of PI3K, Akt, and p-Akt was measured with immunohistochemistry. Two cell lines, BGC-823 and SGC-7901, were transfected and cells were grouped into blank, negative control, COL1A2-shRNA, COL6A3-shRNA, and THBS2-shRNA groups. Expressions of COL1A2, COL6A3, and THBS2 in gastric cancer cells transfected with corresponding silencing sequences were evaluated by RT-qPCR and Western blot. MTT assay, Transwell, and cell scratch tests were conducted to evaluate cell proliferation, invasion, and migration capacity, respectively. Flow cytometry was used to evaluate cell cycle distribution and apoptosis. The positive expression of PI3K, Akt, and p-Akt was higher in gastric cancer tissues compared with adjacent normal tissues, and the mRNA expression of COL1A2, COL6A3, and THBS2 was increased in gastric cancer tissues. Akt, p-Akt, and PI3K expression drastically decreased in cells transfected with COL1A2, COL6A3, and THBS2 silencing sequences. Cells transfected with COL1A2, COL6A3, and THBS2 silencing sequences exhibited promoted apoptosis but inhibited proliferation, migration, and invasion. This study demonstrates that COL1A2, COL6A3, and THBS2 gene silencing inhibits gastric cancer cell proliferation, migration, and invasion while promoting apoptosis through the PI3K-Akt signaling pathway. 

Retracted: Yes

PubPeer comments:
 Fig 3A.  The positive expression of Akt, PI3K (u00d7 200) and p-Akt (u00d7 400) in gastric cancer tissue and adjacent normal tissue Note: A, Protein expression detected by immunohistochemistry . ![file] Two points to consider here. First, that p-Akt for gastric cancer tissue seems to be the same as Akt in normal tissue. Second, the overlap between PI3K in gastric cancer and NGAL in normal tissue - Fig 1A from [Han et al (2018)] . ![file] How two unrelated groups of researchers came to be using the same image (differently titled) is a corundrum. , 
 Fig 5.  Protein expression of the PI3K-Akt signaling pathway-related proteins in BGC-823 cells . ![file] Duplicate blob in 5E. Control bands overlap with Fig 5B from [Yan et al (2019)] . More examples in that thread. ![file] , 
 Fig 7C.  Invasion ability of cells transfected with different silencing sequences by Transwell assay ... C, Invasion ability of SGC-7901 cells . ![file] Fig 11(a) from [Song et al (2019)] .  The comparisons of cell invasion ability after transfection in seven groups. Note: a, The cell invasion image after cell transfection in seven groups . I don t know what happened to the 7th group. ![file] UPDATE: Another sighting! Fig 8B from [Pan et al (2018)] . ![file] , 
 There is a panel similar to one in [Min et al, 2018] . Look at the thick red box. Here figure 7C of this paper: ![file] Here figure 3C of Min et al, 2018 ![file] , 
 #2 Fig 5 again.  Protein expression of the PI3K-Akt signaling pathway-related proteins in BGC-823 cells . ![file] Cyan rectangle marks a similar triad of blobs in Fig 6B of [Long et al (2018)] . ![file] , 
 Retracted [19 July 2021] . ---------------------------------------------- The above article, published online on 16 November 2017 in Wiley Online Library has been retracted by agreement between the journal s Editor in Chief, Prof. Dr. Christian Behl, and Wiley Periodicals LLC. The retraction has been agreed following an investigation based on allegations raised by a third party. A detailed investigation revealed that several image elements of the experimental data were published elsewhere in a different scientific context. Thus, the editors consider the conclusions of this article to be invalid. ,