51. Sohlh2 suppresses epithelial to mesenchymal transition in breast cancer via downregulation of IL-8
- Author
-
Wenfang Zhang, Chunyan Hao, Jing Hao, Aijun Hao, Qing Gao, Shufang Ji, Jinhao Sun, Xiaoli Zhang, and Hongying Zhang
- Subjects
0301 basic medicine ,Pathology ,medicine.medical_specialty ,Epithelial-Mesenchymal Transition ,Down-Regulation ,Breast Neoplasms ,Metastasis ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Breast cancer ,breast cancer ,Cell Movement ,Sohlh2 ,Cell Line, Tumor ,medicine ,Basic Helix-Loop-Helix Transcription Factors ,metastasis ,Animals ,Humans ,Metastasis suppressor ,Neoplasm Invasiveness ,Epithelial–mesenchymal transition ,Neoplasm Metastasis ,Promoter Regions, Genetic ,Cell Proliferation ,Mice, Inbred BALB C ,Wound Healing ,IL-8 ,business.industry ,Interleukin-8 ,EMT ,Cell migration ,medicine.disease ,Metastatic breast cancer ,Gene Expression Regulation, Neoplastic ,030104 developmental biology ,Oncology ,030220 oncology & carcinogenesis ,Cancer cell ,Cancer research ,MCF-7 Cells ,Female ,Ovarian cancer ,business ,Research Paper ,Signal Transduction - Abstract
// Shufang Ji 1, * , Wenfang Zhang 1, * , Xiaoli Zhang 1 , Chunyan Hao 2 , Aijun Hao 1 , Qing Gao 1 , Hongying Zhang 3 , Jinhao Sun 4 , Jing Hao 1 1 Key Laboratory of The Ministry of Education for Experimental Teratology, Department of Histology and Embryology, School of Medicine, Shandong University, Jinan 250012, PR China 2 Department of Pathology, School of Medicine, Shandong University, Jinan 250012, PR China 3 Department of Biology, Jinan Vocational College of Nursing, Jinan 250000, PR China 4 Department of Human Anatomy, School of Medicine, Shandong University, Jinan 250012, PR China * These authors contributed equally to this work Correspondence to: Jing Hao, email: haojing@sdu.edu.cn Keywords: Sohlh2, IL-8, EMT, metastasis, breast cancer Abbreviations: EMT, epithelial-to-mesenchymal transition; Sohlh2, spermatogenesis- and oogenesis- specific basic helix-loop-helix transcription factor2; IL-8, interleukin 8; FBS, fetal bovine serum; ChIP, chromatin immunoprecipitation Received: September 25, 2015 Accepted: June 16, 2016 Published: June 30, 2016 ABSTRACT Breast cancer is one of the deadliest cancers worldwide due to its strong metastasis to other organs. Metastasis of breast cancer involves a complex set of events, including epithelial-mesenchymal transition (EMT) that increases invasiveness of the tumor cells. We previously identified sohlh2 is a tumor suppressor in the pathogenesis of ovarian cancer. However, the functions of sohlh2 in breast cancer cell migration and invasion remain unknown. Here we report a novel sohlh2/IL-8 signaling pathway in the invasive breast cancer. We observed sohlh2 expression was downregulated in the metastatic breast cancer. Ectopic sohlh2 expression in breast cancer cells reduced EMT and inhibited cell migration and invasion in vitro , and metastasis in vivo . Moreover, the depletion of sohlh2 induced the opposite effects to ectopic sohlh2 expression. RNA-Seq data from a sohlh2 knockdown breast cancer cell line showed that after sohlh2 depletion, the mRNA level of interleukin 8 (IL-8) was significantly increased in these cancer cells, which consequently increased secretion of IL-8 protein. Using chromatin immunoprecipitation and reporter assays, we demonstrated that sohlh2 bound to IL-8 promoter and repressed its activities. The enhanced migration and invasion in sohlh2 -ablated MCF-7 cells were blocked by knockdown of IL-8 expression, while exogenous IL-8 neutralized the anti-migratory and invasive activities of sohlh2 in MDA-MB-231cells. Overall, these results demonstrate that sohlh2 functions as a tumor metastasis suppressor via suppressing IL-8 expression in breast cancer.
- Published
- 2016