Affordable Access

Access to the full text

Exosomes Mediated Transfer of Circ_UBE2D2 Enhances the Resistance of Breast Cancer to Tamoxifen by Binding to MiR-200a-3p

  • Hu, Ke
  • Liu, Xianhao
  • Li, Yi
  • Li, Qinyang
  • Xu, Yijun
  • Zeng, Wei
  • Zhong, Guocheng
  • Yu, Changhua
Published Article
Medical Science Monitor
"International Scientific Information, Inc."
Publication Date
Aug 05, 2020
DOI: 10.12659/MSM.922253
PMID: 32756532
PMCID: PMC7431386
PubMed Central


Background Circular RNA UBE2D2 (circ_UBE2D2) has been found to be involved in the progression of breast cancer. Exosomes are critical mediators of intercellular communication, however, the function of exosomal circ_UBE2D2 in breast cancer remains vague. Material/Methods Cell viability was measured by Cell Counting Kit-8 assay. Western blot was used to detect the levels of estrogen receptor alpha (ERα), E-cadherin, vimentin, CD9, and CD63. Migrated and invaded cells were examined using Transwell assay. Circ_UBE2D2 and microRNA (miR)-200a-3p levels were detected using quantitative real-time polymerase chain reaction. Exosomes were isolated by ultracentrifugation method. The interaction between circ_UBE2D2 and miR-200a-3p was confirmed by dual-luciferase reporter assay and RNA immunoprecipitation assay. Murine xenograft model was established to conduct in vivo experiments. Results We found that circ_UBE2D2 was upregulated in breast cancer tamoxifen-resistant tissues and cell lines, and circ_UBE2D2 deletion mitigated tamoxifen resistance in breast cancer cells. Circ_UBE2D2 was also significantly loaded in exosomes isolated from resistant cells and could be transferred to parental cells. MiR-200a-3p was a target of circ_UBE2D2, and we demonstrated that exosomes mediated transfer of circ_UBE2D2 interacted with miR-200a-3p to enhance tamoxifen resistance of breast cancer cells by regulating cell viability, metastasis, and the level of ERα in vivo and in vitro . Conclusions Exosomes mediated transfer of circ_UBE2D2 reinforced tamoxifen resistance in breast cancer by binding to miR-200a-3p, providing new insights into the boost of the effectiveness of tamoxifen on breast cancer patients.

Report this publication


Seen <100 times