HER2/neu gene amplification determines the sensitivity of uterine serous carcinoma cell lines to AZD8055, a novel dual mTORC1/2 inhibitor

Gynecol Oncol. 2013 Dec;131(3):753-8. doi: 10.1016/j.ygyno.2013.08.033. Epub 2013 Sep 4.

Abstract

Objective: To evaluate c-erbB2 gene amplification in a series of primary uterine serous carcinoma (USC) cell lines. To assess the efficacy of AZD8055, a novel dual mTORC1/2 inhibitor against primary HER2/neu amplified vs HER2/neu not amplified USC cell lines.

Methods: Twenty-two primary USC cell lines were evaluated for c-erbB2 oncogene amplification by FISH assays. In vitro sensitivity to AZD8055 was evaluated by flow-cytometry-based viability and proliferation assays. Cell cycle profile and downstream cellular responses to AZD8055 were assessed by measuring the DNA content of cells and by phosphorylation of the S6 protein by flow-cytometry.

Results: Nine of 22 (40.9%) USC cell lines demonstrated c-erbB2 gene amplification by FISH. AZD8055 caused a strong differential growth inhibition in USC cell lines, with high HER-2/neu-expressors demonstrating significantly higher sensitivity when compared to low HER-2/neu-expressors (AZD-8055 IC50 mean±SEM=0.27±0.05μM in c-erbB2 amplified versus 1.67±0.68μM in c-erbB2 not amplified tumors, P=0.03). AZD8055 growth-inhibition was associated with a significant and dose-dependent increase in the percentage of cells blocked in the G0/G1 cell cycle phase and a dose-dependent decline in pS6 levels in both c-erbB2 amplified vs c-erbB2 not amplified USC cell lines.

Conclusions: AZD8055 may represent a novel targeted therapeutic agent in patients harboring advanced/recurrent/refractory USC. c-erbB2 gene amplification may represent a biomarker to identify USC patients who may benefit most from the use of AZD8055.

Keywords: Endometrial neoplasms; HER2/neu; Uterine serous tumors; mTOR inhibitor AZD8055.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Antineoplastic Agents / pharmacology
  • Carcinoma, Papillary / drug therapy*
  • Carcinoma, Papillary / enzymology
  • Carcinoma, Papillary / genetics
  • Cell Line, Tumor
  • Cystadenocarcinoma, Serous / drug therapy*
  • Cystadenocarcinoma, Serous / enzymology
  • Cystadenocarcinoma, Serous / genetics
  • Female
  • Gene Amplification
  • Humans
  • Mechanistic Target of Rapamycin Complex 1
  • Mechanistic Target of Rapamycin Complex 2
  • Morpholines / pharmacology*
  • Multiprotein Complexes / antagonists & inhibitors
  • Protein Kinase Inhibitors / pharmacology
  • Receptor, ErbB-2 / genetics*
  • TOR Serine-Threonine Kinases / antagonists & inhibitors
  • Uterine Neoplasms / drug therapy*
  • Uterine Neoplasms / enzymology
  • Uterine Neoplasms / genetics

Substances

  • Antineoplastic Agents
  • Morpholines
  • Multiprotein Complexes
  • Protein Kinase Inhibitors
  • (5-(2,4-bis((3S)-3-methylmorpholin-4-yl)pyrido(2,3-d)pyrimidin-7-yl)-2-methoxyphenyl)methanol
  • ERBB2 protein, human
  • Receptor, ErbB-2
  • Mechanistic Target of Rapamycin Complex 1
  • Mechanistic Target of Rapamycin Complex 2
  • TOR Serine-Threonine Kinases