Paeoniflorin Sensitizes Breast Cancer Cells to Tamoxifen by Downregulating microRNA-15b via the FOXO1/CCND1/β-Catenin Axis

Yanhong Wang,1,2 Qian Wang,1 Xibei Li,3 Gongwen Luo,2 Mou Shen,2 Jia Shi,4 Xueliang Wang,5 Lu Tang6 1Department of Basic Medicine, Medical College of Yunnan University of Economics and Management, Kunming, Yunnan 650000, People’s Republic of China; 2Second Department of Internal Medicine, Chongming Branch of Yueyang Integrated Hospital of Traditional Chinese and Western Medicine Affiliated to Shanghai University of Traditional Chinese Medicine, Chongming, Shanghai, 202150, People’s Republic of China; 3Department of Stomatology, Jining Medical College, Jining, Shandong 272000, People’s Republic of China; 4Department of Information, The First Affiliated Hospital of Naval Military Medical University (Shanghai Changhai Hospital), Shanghai 200433, People’s Republic of China; 5Department of Nephrology and Rheumatology, Zhaotong Traditional Chinese Medicine Hospital of Yunnan Province, Zhaotong, Yunnan 657000 People’s Republic of China; 6Department of Traditional Chinese Medicine, Kunming Second People’s Hospital, Kunming, Yunnan, 650000 People’s Republic of ChinaCorrespondence: Lu TangDepartment of Traditional Chinese Medicine, Kunming Second People’s Hospital, No. 672 Longquan Road, Panlong District, Kunming, Yunnan 650000, People’s Republic of ChinaEmail tanglu11610@163.comBackground: Paeoniflorin (Pae) possesses anti-tumor activity in various malignancies. However, it is unclear whether Pae plays a sensitizer role in breast cancer (BC) and the molecular mechanisms involved in this process. Our oligonucleotide microarray revealed that microRNA (miR)-15b is the most significantly downregulated miRNA in MCF-7/4-hydroxytamoxifen (4-OHT) cells treated with Pae. This paper summarized the relevance of Pae in BC cell endocrine resistance to tamoxifen (Tam) and the molecular mechanisms involved miR-15b expression.Materials and Methods: 4-OHT-resistant BC cell lines were developed and treat