Gangping WANG,Huifang Shi,Jingjing Li,Lei Chen,Shuguang Yang,Ying Zhao,Zuofeng Zhang,
Downregulation of miR-142-3p Contributes to Breast Cancer Oncogenesis
Clinical Oncology and Research
2019
2613-4942
http://dx.doi.org/10.31487/j.COR.2019.6.11
https://www.sciencerepository.org/downregulation-of-mir-142-3p_COR-2019-6-111 
Abstract: Breast cancer is one of the commonly-encountered malignant tumors, and its morbidity is on the rise year
by year. A better understanding of the molecular mechanisms of breast cancer is important. This can
improve the prevention, diagnosis, and treatment.The miR-142‐3p has been shown to inhibit carcinogenesis
by regulating various cellular processes, including cell cycle progression, cell migration, apoptosis, and
invasion. We surgically recruited 96 breast cancer patients and the breast cancer samples, each with matched
adjacent normal breast tissue were obtained, MDA-MB-231 and MCF-7 cells were cultured for experiments
in vitro and measured the expression of miR‐142‐3p via quantitative real‐time polymerase chain reaction
(qRT‐PCR). Cell viability, apoptosis, migration, and invasion were determined by MTT, flow cytometry,
and trans-well assays. The expression of miR-142-3p was down-regulated in both cancer cell lines and
cancer specimens. The reduced expression of miR-142‐3p was associated with tumor size, lymph node
metastasis, and tumor-node-metastasis (TNM) stage of patients (p<0.05). However, there was no significant
correlation between miR‐142‐3p expression in tumor tissues with age at diagnosis (p>0.05). Overexpression
of miR-142-3p repressed cell viability, migration, and invasion, while it induced apoptosis, whereas its
depletion promoted it. The results suggest miR‐142‐3p acts as a tumor suppressor and can act as a novel
target for the treatment of breast cancer. Thus, restoration of miR‐142‐3p expression, for example, via
miRNA replacement therapy, may represent an effective strategy for the treatment of breast cancer patientsKeywords: Breast cancer, miR-142-3p, apoptosis, migration, invasion