Circular RNA circ-PRKCI promotes cell proliferation and invasion by binding to microRNA-545 in gastric cancer
Authors: X Zhu
X-M Xu
L Wu
Y Li
Journal: European review for medical and pharmacological sciences (2019)
Discipline: PHARMACOLOGY & TOXICOLOGY
Keywords: circ-PRKCI; gastric cancer; expression; regulation mechanism; proliferation
Affiliations: Department of Oncology, Renmin Hospital of Wuhan University, Wuhan, China. .

Abstract:  Objective: The carcinogenic effects of circular RNA circ-PRKCI have been recognized in a variety of malignancies. However, the exact biological function of circ-PRKCI in gastric cancer has not been fully elucidated. Therefore, the aim of this study was to explore the expression of circ-PRKCI in gastric cancer (GC) and to investigate its potential regulation mechanism in the pathogenesis and progression of GC. Patients and methods: The expression of circ-PRKCI in 50 GC tissues and cell lines was detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Statistical methods were used to analyze the relation between circ-PRKCI expression and overall survival rate of patients. The effect of circ-PRKCI on GC cell proliferation was examined by cell counting kit-8 (CCK-8) and cell colony formation assays. Meanwhile, the effect of circ-PRKCI on the invasion ability of GC cells was determined by transwell invasion assay. Flow cytometry was used to detect the apoptosis of GC cells. Bioinformatics was used to search for miRNAs that might have direct effects with circ-PRKCI. In addition, the binding of circ-PRKCI to microRNA-545 was validated using Dual-Luciferase reporter gene assay. Results: Circ-PRKCI was significantly highly expressed in GC tissues, as well as cell lines. High expression of circ-PRKCI was positively associated with a poor prognosis of GC patients. Overexpression of circ-PRKCI significantly promoted the proliferation and invasion of GC cells, whereas reduced the proportion of apoptotic GC cells. Subsequent Dual-Luciferase reporter gene assay revealed that circ-PRKCI could bind to microRNA-545 and inhibit its expression in GC cells. These results indicated that circ-PRKCI might promote the development of GC by adsorbing microRNA-545 in a sponge manner. Conclusions: Circ-PRKCI can be used as a potential prognostic indicator of GC, providing a new perspective for the potential bio-molecular mechanism in GC. 

Retracted: No

PubPeer comments:
  Tissues were obtained from patients undergoing radical resection at Renmin Hospital of Wuhan University from **March 2016 to October 2018**. Fig 1E.  Kaplan-Meier was used to plot the survival curves of GC patients in circ-PRKCI high-expression group and circ-PRKCI low-expression group. ![file] When this paper was published in November 2019, the authors had followed the patients survival for nearly 5 years after recruitment, i.e. through to the date range **early 2021 to mid-2023**. , 
 #1 Dear expert Thank you for your valuable comments. Because of COVID-19 s reason, we only know your question now. For this serious error, we will check the original data immediately. We have corrected the statistical error and contacted the Editorial Office. Thanks again. Wu L , 
 [Correction, January 2022] . ------------------------------------ After publication, the authors applied to change Figure 1E stating that u201cgastric cancer was observed from patients underlying response at Renmin Hospital of Wuhan University from March 2015 to March 2016. By the time of submission, the survival time of follow-up was only 2 years. From the 2-year follow-up data, we found that high expression of CIRC PRKCI was positively associated with a poor prognosis of GC patientsu201d. The authors claim that there is no serious change in the conclusion of the article. ![file] --------------------------- When you originally claim that patients survived up to 5 years, then replace that with another group of patients who only survived up to 2 years, this strikes me as a **massive** change in conclusions. 5-year survival time for GC is usually more like 70%, so I have to accuse this hospital of murderous incompetence. ,