title: Fluoxetine induces cytotoxic endoplasmic reticulum stress and autophagy in triple negative breast cancer.
abstract: OBJECTIVE
  To investigate the mechanism of action of lipophilic antidepressant fluoxetine (FLX) in representative molecular subtypes of breast cancer.
  
  
  METHODS
  The anti-proliferative effects and mechanistic action of FLX in triple-negative (SUM149PT) and luminal (T47D and Au565) cancer cells and non-transformed MCF10A were investigated. Reverse phase protein microarray (RPPM) was performed with and without 10 μmol/L FLX for 24 and 48 h to determine which proteins are significantly changed. Viability and cell cycle analysis were also performed to determine drug effects on cell growth. Western blotting was used to confirm the change in protein expression examined by RPPM or pursue other signaling proteins.
  
  
  RESULTS
  The FLX-induced cell growth inhibition in all cell lines was concentration- and time-dependent but less pronounced in early passage MCF10A. In comparison to the other lines, cell growth reduction in SUM149PT coincided with significant induction of endoplasmic reticulum (ER) stress and autophagy after 24 and 48 h of 10 μmol/L FLX, resulting in decreased translation of proteins along the receptor tyrosine kinase/Akt/mammalian target of rapamycin pathways. The increase in autophagy marker, cleaved microtubule-associated protein 1 light chain 3, in SUM149PT after 24 h of FLX was likely due to increased metabolic demands of rapidly dividing cells and ER stress. Consequently, the unfolded protein response mediated by double-stranded RNA-dependent protein kinase-like ER kinase resulted in inhibition of protein synthesis, growth arrest at the G1 phase, autophagy, and caspase-7-mediated cell death.
  
  
  CONCLUSIONS
  Our study suggests a new role for FLX as an inducer of ER stress and autophagy, resulting in death of aggressive triple negative breast cancer SUM149PT.
authors.affiliation: Michelle Bowie, Siya Lem, Abigail Hoffman, Shraddha Desai, Amira Carter, Adrian Ambrose, Victoria Seewaldt, Catherine Ibarra Drendall, Department of Medicine, Division of Medical Oncology, Duke University Medical Center, Durham, NC 27710, United States.
authors.forename: Michelle
authors.initials: M
authors.lastname: Bowie
authors.affiliation: Michelle Bowie, Siya Lem, Abigail Hoffman, Shraddha Desai, Amira Carter, Adrian Ambrose, Victoria Seewaldt, Catherine Ibarra Drendall, Department of Medicine, Division of Medical Oncology, Duke University Medical Center, Durham, NC 27710, United States.
authors.forename: Patrick
authors.initials: P
authors.lastname: Pilie
authors.affiliation: Michelle Bowie, Siya Lem, Abigail Hoffman, Shraddha Desai, Amira Carter, Adrian Ambrose, Victoria Seewaldt, Catherine Ibarra Drendall, Department of Medicine, Division of Medical Oncology, Duke University Medical Center, Durham, NC 27710, United States.
authors.forename: Julia
authors.initials: J
authors.lastname: Wulfkuhle
authors.affiliation: Michelle Bowie, Siya Lem, Abigail Hoffman, Shraddha Desai, Amira Carter, Adrian Ambrose, Victoria Seewaldt, Catherine Ibarra Drendall, Department of Medicine, Division of Medical Oncology, Duke University Medical Center, Durham, NC 27710, United States.
authors.forename: Siya
authors.initials: S
authors.lastname: Lem
authors.affiliation: Michelle Bowie, Siya Lem, Abigail Hoffman, Shraddha Desai, Amira Carter, Adrian Ambrose, Victoria Seewaldt, Catherine Ibarra Drendall, Department of Medicine, Division of Medical Oncology, Duke University Medical Center, Durham, NC 27710, United States.
authors.forename: Abigail
authors.initials: A
authors.lastname: Hoffman
authors.affiliation: Michelle Bowie, Siya Lem, Abigail Hoffman, Shraddha Desai, Amira Carter, Adrian Ambrose, Victoria Seewaldt, Catherine Ibarra Drendall, Department of Medicine, Division of Medical Oncology, Duke University Medical Center, Durham, NC 27710, United States.
authors.forename: Shraddha
authors.initials: S
authors.lastname: Desai
authors.affiliation: Michelle Bowie, Siya Lem, Abigail Hoffman, Shraddha Desai, Amira Carter, Adrian Ambrose, Victoria Seewaldt, Catherine Ibarra Drendall, Department of Medicine, Division of Medical Oncology, Duke University Medical Center, Durham, NC 27710, United States.
authors.forename: Emanuel
authors.initials: E
authors.lastname: Petricoin
authors.affiliation: Michelle Bowie, Siya Lem, Abigail Hoffman, Shraddha Desai, Amira Carter, Adrian Ambrose, Victoria Seewaldt, Catherine Ibarra Drendall, Department of Medicine, Division of Medical Oncology, Duke University Medical Center, Durham, NC 27710, United States.
authors.forename: Amira
authors.initials: A
authors.lastname: Carter
authors.affiliation: Michelle Bowie, Siya Lem, Abigail Hoffman, Shraddha Desai, Amira Carter, Adrian Ambrose, Victoria Seewaldt, Catherine Ibarra Drendall, Department of Medicine, Division of Medical Oncology, Duke University Medical Center, Durham, NC 27710, United States.
authors.forename: Adrian
authors.initials: A
authors.lastname: Ambrose
authors.affiliation: Michelle Bowie, Siya Lem, Abigail Hoffman, Shraddha Desai, Amira Carter, Adrian Ambrose, Victoria Seewaldt, Catherine Ibarra Drendall, Department of Medicine, Division of Medical Oncology, Duke University Medical Center, Durham, NC 27710, United States.
authors.forename: Victoria
authors.initials: V
authors.lastname: Seewaldt
authors.affiliation: Michelle Bowie, Siya Lem, Abigail Hoffman, Shraddha Desai, Amira Carter, Adrian Ambrose, Victoria Seewaldt, Catherine Ibarra Drendall, Department of Medicine, Division of Medical Oncology, Duke University Medical Center, Durham, NC 27710, United States.
authors.forename: Dihua
authors.initials: D
authors.lastname: Yu
authors.affiliation: Michelle Bowie, Siya Lem, Abigail Hoffman, Shraddha Desai, Amira Carter, Adrian Ambrose, Victoria Seewaldt, Catherine Ibarra Drendall, Department of Medicine, Division of Medical Oncology, Duke University Medical Center, Durham, NC 27710, United States.
authors.forename: Catherine
authors.initials: C
authors.lastname: Ibarra Drendall
keywords: Apoptosis; Autophagy; Endoplasmic reticulum stress; Fluoxetine; Inflammatory breast cancer