Synergistic antitumor effects of S-1 with eribulin in vitro and in vivo for triple-negative breast cancer cell lines

Masato Terashima, Kazuko Sakai, Yosuke Togashi, Hidetoshi Hayashi, Marco A. De Velasco, Junji Tsurutani, Kazuto Nishio

Research output: Contribution to journalArticlepeer-review

29 Citations (Scopus)


Triple-negative breast cancer (TNBC) is associated with a higher incidence of recurrence and distant metastasis and a poor prognosis, whereas effective treatment strategies remain to be established. Finding an effective treatment for TNBC has become imperative. We examined the effect of the combination of S-1 (or 5-FU in an in vitro study) and eribulin in TNBC cell lines. The in vitro effect of the combination was examined in four TNBC cell lines (MDA-MB-231, MDA-MB-468, BT-549 and MX-1) using a combination index and isobolograms. In addition, we assessed the effect of the combination in an MDA-MB-231 tumor xenograft model. A synergistic effect was observed in three TNBC cell lines (MDA-MB-231, MDA-MB-468, and MX-1), and in an in vivo study, the combination of S-1 and eribulin resulted in significantly higher antitumor effects compared with S-1 or eribulin alone. 5-FU induced epithelial-mesenchymal transition (EMT) change in the TNCB cell line, as supported by the decreased expression of epithelial marker and the increased expression of mesenchymal markers. Meanwhile, TGF-beta induced EMT changes in a TNBC cell line and decreased the sensitivity to 5-FU. This result suggests that 5-FU-induced EMT changes reduce the sensitivity to 5-FU. In contrast, eribulin induced a mesenchymal-epithelial transition (MET) in a TNBC cell line. The EMT phenotype induced by 5-FU was also canceled by eribulin. We demonstrate that the combination of S-1 (5-FU) and eribulin exerts a synergistic effect for TNBC cell lines through MET-induction by eribulin. Therefore, this combination therapy may be a potential treatment option for TNBC.

Original languageEnglish
Article number417
Pages (from-to)1-11
Number of pages11
Issue number1
Publication statusPublished - 2014
Externally publishedYes


  • 5-FU
  • EMT
  • Eribulin
  • MET
  • S-1
  • TNBC

ASJC Scopus subject areas

  • General


Dive into the research topics of 'Synergistic antitumor effects of S-1 with eribulin in vitro and in vivo for triple-negative breast cancer cell lines'. Together they form a unique fingerprint.

Cite this