MiRNA-221-5p promotes breast cancer progression by regulating E-cadherin expression
Authors: Z-Q Zhang
X-Y Niu
P-L Ma
Journal: European review for medical and pharmacological sciences (2019)
Discipline: PHARMACOLOGY & TOXICOLOGY
Keywords: miRNA-221-5p; breast cancer; metastasis; E-cadherin; qRT-PCR
Affiliations: Department of Thyroid and Breast Surgery, Bayannur City Hospital, Bayannur, China. .

Abstract:  Objective: To elucidate the role of miRNA-221-5p in the development of breast cancer (BCa) and its underlying mechanism. Patients and methods: The expression level of miRNA-221-5p in 52 pairs of BCa tissues and adjacent normal tissues was detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The correlation between miRNA-221-5p expression and pathological indicators of BCa was analyzed. MiRNA-221-5p expression in BCa cells was also determined by qRT-PCR. After transfection of miRNA-221-5p inhibitor in MCF-7 and SKBR3 cells, we detected the regulatory effects of miRNA-221-5p on cellular behaviors through cell counting kit-8 (CCK-8), wound healing, and transwell assay. Finally, the relationship between miRNA-221-5p and E-cadherin in BCa was elucidated. Results: QRT-PCR results showed that the expression level of miRNA-221-5p in BCa tissues was markedly higher than that in normal tissues. Compared with BCa patients with low expression of miRNA-221-5p, those with high expression had a higher incidence of lymph node metastasis and distant metastasis. However, miRNA-221-5p expression did not correlate with age and sex of BCa patients. MiRNA-221-5p was also highly expressed in BCa cells. Transfection of miRNA-221-5p inhibitor suppressed proliferative, invasive, and migratory potentials of BCa cells. Subsequently, we verified that E-cadherin was lowly expressed in BCa cells, and negatively correlated with miRNA-221-5p. In addition, rescue experiments confirmed that transfection of si-E-cadherin reversed the inhibitory role of miRNA-221-5p knockdown in migratory and invasive potentials of BCa cells. Conclusions: The expression of miRNA-221-5p remained high in BCa, which was correlated with lymph node metastasis, distant metastasis, and poor prognosis of BCa. MiRNA-221-5p may promote the invasive and migratory potentials of BCa by regulating E-cadherin expression. 

Retracted: No

PubPeer comments:
 Figure 2C. * Red boxes: Two panels appear to show an overlap. ![file] , 
 Some additional concerns. The paper describes 52 breast cancer patients. According to Table 1, about half of these were male. Now, it is not impossible that men get breast cancer, but it is rare, so this gender ratio is very surprising. ![file] , 
 Figure 3. * The correlation plot shown here is surprisingly similar to that of C. Liu et al., doi: 10.26355 eurrev_201902_17116, which is also similar to that of several others, as pointed out by Hoya Camphorifolia at https: pubpeer.com publications 2D5E1F90B735BE8C2A9CA2601C4044 Here is a small collage of the plots. I have highlighted some characteristic data points with colored ellipses. ![file] , 
 #3 Here, an overlay of 20 correlation scatterplots from various papers (all based on the same spreadsheet), emphasising the points frequently occurring between them. ![file] ,