Retracted : Effects of shRNA‐Mediated Silencing of PKM2 Gene on Aerobic Glycolysis, Cell Migration, Cell Invasion, and Apoptosis in Colorectal Cancer Cells
Authors: Ran Ao
Lin Guan
Xue-Bin Zhang
Xiao-Ling Yan
Journal: Journal of Cellular Biochemistry (2017)
Discipline: MOLECULAR BIOLOGY & GENETICS
Keywords: AEROBIC GLYCOLYSIS; APOPTOSIS; COLORECTAL CANCER; GENE SILENCING; INVASION
Affiliations: Department of Pathology, Tianjin Huanhu Hospital, Tianjin 300350, P. R. China., Tianjin Key Laboratory of Cerebral Vascular and Neurodegenerative Diseases, Tianjin 300350, P. R. China., Department of Gastroenterology, The First Hospital of China Medical University, Shenyang 110001, P. R. China.

Abstract:  This study aims to explore the effects of shRNA-mediated silencing on Pyruvate kinase type M2 (PKM2) gene during aerobic glycolysis in colorectal cancer (CRC) cells. CRC tissues and adjacent normal tissues were obtained from 136 patients diagnosed with qRT-PCR, Western blotting, and immunohistochemistry (IHC) were performed to detect mRNA and protein expressions of PKM2. CRC cells were divided into a blank, vector, and PKM2-shRNA groups. Hexokinase (HK) and PKM2 activity were both determined by glucose-6-phosphate dehydrogenase (G-6-PD) coupled colorimetric assay and enzyme coupling rate method. The extracellular lactate concentration was measured by ultraviolet spectrophotometer and caspase activity was measured using spectrophotometry. The proliferation, cell cycle, apoptosis, invasion, and migration of CRC cells were detected by cell counting kit-8 (CCK-8) assay, flow cytometry, transwell assay, and scratch test. Three groups of nude mice were injected with 0.2 mL single-cell suspension from the blank, vector, and PKM2-shRNA groups, respectively. PKM2 protein content in CRC tissues was higher than that in adjacent normal tissues. Results showed that the PKM2-shRNA group exhibited significantly lower mRNA and protein expressions of PKM2, decreased PKM2 activity, reduced lactate metabolism level, increased cell apoptosis rate, elevated caspase-3 and caspase-9 activity, weakened proliferation, and a reduction in cell invasion and migration ability compared to the vector and blank groups. The optical density (OD) value was lower in the PKM2-shRNA group than in the blank and vector groups. These findings indicate that shRNA-mediated silencing of PKM2 gene promotes apoptosis and inhibits aerobic glycolysis, proliferation, migration, and invasion in CRC cells. J. Cell. Biochem. 118: 4792-4803, 2017. © 2017 Wiley Periodicals, Inc. 

Retracted: Yes

PubPeer comments:
 I am unfortunately having problems understanding your design of a source of cesium atoms, since it is unusual. What distribution of your atoms in the beam did you wish to achieve? Your figure 6 shows a near-cosine distributon. This can easily be obtained with a simple thin nozzle. The expressions for the beam properties are then much simpler. You also mention a Gaussian flux distribution. What is that? What is the purpose of the cap on your nozzle tube and what do the dotted lines along its length in your Figure 2 (a) signify? You might find the book by C B Lucas with the title:  Atomic and Molecular Beams: Production and collimation (2013) of use if you wish to produce a directed atomic beam of cesium and wish to avoid detailed calculations. , 
 Presumably both authors with e-mail ids given in the paper were made aware that there was a comment for them? It is a disappointment that you have not so far replied, since clearly it is of interest to know more about your unusual design of a cesium atomic beam source. Please acknowledge that you have seen these comments. , 
 #2 You may wish to add the author email addresses using the PubPeer button on this page, if you havenu2019t already done so. Iu2019m not aware that the system does this automatically, but I may be wrong. , 
 Thank you for the suggstion. I hadn t spotted that button. Unfortunately it is clear from contributions in general that very few authors choose to reply to comments, which must be a disappointment to those making them. ,