title: Estrogen receptor-α36 is involved in epigallocatechin-3-gallate induced growth inhibition of ER-negative breast cancer stem/progenitor cells.
abstract: Epigallocatechin-3-gallate (EGCG) is a type of catechin extracted from green tea, which is reported to have anticancer effects. EGCG is also reported to inhibit the cancer stem/progenitor cells in several estrogen receptor (ER)-negative breast cancer cell lines, such as SUM-149, SUM-190 and MDA-MB-231. And all these cancer cells are highly expressed a new variant of ER-α, ER-α36. The aim of our present study is to determine the role of ER-α36 in the growth inhibitory activity of EGCG towards ER-negative breast cancer MDA-MB-231 and MDA-MB-436 cells. We found that EGCG potently inhibited the growth of cancer stem/progenitor cells in MDA-MB-231 and MDA-MB-436 cells, and also reduced the expression of ER-α36 in these cells. However, in ER-α36 knocked-down MDA-MB-231 and MDA-MB-436 cells, no significant inhibitory effects of EGCG on cancer stem/progenitor cells were observed. We also found that down-regulation of ER-α36 expression was in accordance with down-regulation of EGFR, which further verified a loop between ER-α36 and EGFR. Thus, our study indicated ER-α36 is involved in EGCG's inhibitory effects on ER-negative breast cancer stem/progenitor cells, which supports future preclinical and clinical evaluation of EGCG as a therapeutic option for ER-α36 positive breast cancer.
authors.affiliation: Department of Breast and Thyroid Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Jinan 250021, Shandong, China. Electronic address: pxh1997@126.com.
authors.forename: Xiaohua
authors.initials: X
authors.lastname: Pan
authors.affiliation: Department of Genetics and Key Laboratory for Experimental Teratology of the Ministry of Education, Shandong University, Jinan 250012, Shandong, China. Electronic address: 472946565@qq.com.
authors.forename: Bowen
authors.initials: B
authors.lastname: Zhao
authors.affiliation: Department of Genetics and Key Laboratory for Experimental Teratology of the Ministry of Education, Shandong University, Jinan 250012, Shandong, China. Electronic address: 15169193767@163.com.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Song
authors.affiliation: Department of Genetics and Key Laboratory for Experimental Teratology of the Ministry of Education, Shandong University, Jinan 250012, Shandong, China. Electronic address: hanshuaifei1987@163.com.
authors.forename: Shuai
authors.initials: S
authors.lastname: Han
authors.affiliation: Department of Genetics and Key Laboratory for Experimental Teratology of the Ministry of Education, Shandong University, Jinan 250012, Shandong, China. Electronic address: wml@sdu.edu.cn.
authors.forename: Molin
authors.initials: M
authors.lastname: Wang
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D001943:Breast Neoplasms / Q000235:genetics* / Q000473:pathology*; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology; D002471:Cell Transformation, Neoplastic / Q000187:drug effects*; D002478:Cells, Cultured; D015536:Down-Regulation / Q000187:drug effects / Q000235:genetics; D047628:Estrogen Receptor alpha / Q000235:genetics* / Q000502:physiology; D015870:Gene Expression / Q000187:drug effects / Q000235:genetics; D006801:Humans; D014411:Neoplastic Stem Cells / Q000473:pathology*
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D047628:Estrogen Receptor alpha; D002392:Catechin; C045651:epigallocatechin gallate
keywords: Cancer stem/progenitor cells; ER-α36; Epigallocatechin-3-gallate; Epithelial growth factor receptor