RETRACTED: Hsa_circ_002178 Promotes the Growth and Migration of Breast Cancer Cells and Maintains Cancer Stem-like Cell Properties Through Regulating miR-1258/KDM7A Axis

Abstract

Breast cancer (BrCa) is the most common malignancy in women. Accumulating evidence demonstrated that abnormal circRNA expression is associated with the occurrence and progression of tumors. We analyzed the GSE101123 data and found that the expression of hsa_circ_002178 (circ_002178) was significantly increased in BrCa tissues. However, the role and possible underlying mechanisms of circ_002178 in BrCa still remain unrevealed. In this investigation, the expression levels of circ_002178 in cancer tissues or BrCa cells were significantly upregulated compared with those in paracancer tissues or normal cells. High expression of circ_002178 was correlated with the low survival rate, clinical tumor size, lymph node metastasis, and tumor, nodes, and metastases grade. After microsphere culture, the expression of circ_002178 in SUM149PT and MDA-MB-231 cells was significantly increased. Further investigation exhibited that overexpression of circ_002178 contributed to the formation of microspheres, the elevated protein levels of stemness marker, and the increased activity of ALDH1 in SUM149PT cells. Besides, the overexpression of circ_002178 also significantly promoted the growth, invasion, and migration of BrCa cells. Correspondingly, the knockdown of circ_002178 showed the opposite result in MDA-MB-231 cells. Hsa_circ_002178 was further proved to downregulate the level of miR-1258 and reduce the inhibitory effect of miR-1258 on KDM7A, thus regulating the stem-like characteristics of BrCa cells and promoting the growth and migration of BrCa cells. Taken together, targeting the circ_002178/miR-1258/KDM7A axis may be a prospective strategy for the diagnosis and therapies of BrCa in the future.

Prognostic significance of circRNAs expression in breast carcinoma patients: A meta-analysis

“…Cut-off values of high or low circRNA expression were mostly median or mean.The range of mean duration of follow□up was from 30 to 250 months.Moreover,Detection methods of circRNA expression were mainly quantitative real□time polymerase chain reaction (RT□PCR).Sample types were almost from tissues. As for clinical outcome indicators, 27 studies[10, 11, 13-34],[35-37]included overall survival (OS), 5 studies[19, 29, 31, 33, 38]included disease-free survival (DFS).As shown in Table 3, nineteen types of circRNAs were recognized as tumor promoters and nine were tumor suppressors. 28 circrnas have corresponding targets and can promote or inhibit the proliferation, invasion and metastasis of breast cancer cells.…”

A Novel circRNA hsa_circRNA_002178 as a Diagnostic Marker in Hepatocellular Carcinoma Enhances Cell Proliferation, Invasion, and Tumor Growth by Stabilizing SRSF1 Expression

“…In the present study, our study displayed that the hsa_circRNA_002178 level was rose in HCC. It has been reported that hsa_circRNA_002178 was upregulated in breast cancer cells and tissues and regulates breast cancer biological functions, such as proliferation, migration, invasion, and apoptosis [ 18 ]. Besides, Wang et al study found that the strong expression of hsa_circRNA_002178 was detected in exosomes from the plasma of lung adenocarcinoma patients and may serve as a biomarker for the early diagnosis of lung adenocarcinoma [ 19 ].…”

Cancer Stem Cells—The Insight into Non-Coding RNAs

“…hsa_circ_002178 exerts its function by binding miR-1258 to upregulate KDM7A. The expression of circRNA circ_002178 correlates with the survival rate, tumor size, lymph node metastasis, and TNM stage of tumor patients [ 149 ].…”