Nogo-B receptor increases the resistance of estrogen receptor positive breast cancer to paclitaxel

Cancer Lett. 2018 Apr 10:419:233-244. doi: 10.1016/j.canlet.2018.01.054. Epub 2018 Feb 2.

Abstract

Intrinsic or acquired chemoresistance is a hurdle in oncology. Only 7%-16% of estrogen receptor α (ERα) positive breast cancer cases achieve a pathological complete response (pCR) after neo-adjuvant chemotherapy. Nogo-B receptor (NgBR) is a cell surface receptor that binds farnesylated Ras and promotes Ras translocation to the plasma membrane. Here, we demonstrate NgBR as a potential therapeutic target for ERα positive breast cancer patients to attenuate paclitaxel resistance. NgBR knockdown enhanced paclitaxel-induced cell apoptosis by modulating expression of p53 and survivin in ERα positive breast cancer cells via NgBR-mediated PI3K/Akt and MAPK/ERK signaling pathways. NgBR knockdown attenuated either 17β-estradiol or epidermal growth factor stimulated phosphorylation of ERα at Serine 118 residue. The ChIP-PCR assay further demonstrated that NgBR knockdown decreased ERα binding to the estrogen response element (ERE) of the ERα target gene and increased the binding of p53 to the promoter region of survivin to attenuate survivin transcription. In summary, our data suggest that NgBR expression is essential to promoting ERα positive breast cancer cell resistance to paclitaxel. Findings from this study implicate a novel therapeutic target for treating ERα positive breast cancer in neo-adjuvant/adjuvant chemotherapy.

Keywords: Breast cancer; Estrogen receptor; Nogo-B receptor; Paclitaxel; Survivin; p53.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antineoplastic Agents, Phytogenic / therapeutic use
  • Apoptosis / drug effects
  • Apoptosis / genetics
  • Breast Neoplasms / drug therapy*
  • Breast Neoplasms / genetics
  • Breast Neoplasms / metabolism
  • Cell Line, Tumor
  • Drug Resistance, Neoplasm / drug effects*
  • Drug Resistance, Neoplasm / genetics
  • Estradiol / pharmacology
  • Estrogens / pharmacology
  • Female
  • Gene Expression Regulation, Neoplastic / drug effects
  • Humans
  • MCF-7 Cells
  • Paclitaxel / therapeutic use*
  • Phosphorylation / drug effects
  • RNA Interference
  • Receptors, Cell Surface / genetics
  • Receptors, Cell Surface / metabolism*
  • Receptors, Estrogen / metabolism*

Substances

  • Antineoplastic Agents, Phytogenic
  • Estrogens
  • NUS1 protein, human
  • Receptors, Cell Surface
  • Receptors, Estrogen
  • Estradiol
  • Paclitaxel