title: Bromocriptine Induces Autophagy-Dependent Cell Death in Pituitary Adenomas.
abstract: BACKGROUND
  Bromocriptine (BRC) is effective in patients with prolactinoma. However, the cytotoxic mechanism of BRC remains unknown.
  
  
  METHODS
  Slices for immunohistochemical pathology were randomly selected from 37 paraffin-embedded prolactinoma tissue sections. LC3 was detected by immunohistochemistry. GH3 and MMQ cells were treated by BRC and/or rapamycin (RAPA). Cell viability and the cell cycle were measured by CCK-8 and flow cytometry, respectively. Enzyme-linked immunosorbent assay measured prolactin secretion. Protein expression was detected by Western blot or immunofluorescence.
  
  
  RESULTS
  LC3 was significantly expressed in prolactinoma in which patients were treated exclusively with BRC. LC3 expression was negative in normal tissues and prolactinoma in which patients were not treated with BRC. Treatment with 60 μM BRC for 24 hours induced cell death in MMQ cells by up to 50%. However, 110 μM BRC was required to produce a similar effect in GH3 cells. The cell cycle was arrested at the G0-G1phase and S phase. As the concentration and time increased, the conversion ratio of LC3-I to LC3-II increased and prolactin secretion decreased. In addition, Bcl-2 and BAX expression was decreased. The cell viability, prolactin level, and G0-G1cells are similar in MMQ cells treated with RAPA and a low concentration of BRC and MMQ cells treated with a high concentration of BRC. Compared with the effects of a high concentration of BRC, treatment with RAPA and a low concentration of BRC effectively increase the conversion rate of LC3-I to LC3-II.
  
  
  CONCLUSIONS
  BRC-treated pituitary adenoma cells mainly underwent autophagic cell death rather than apoptosis.
authors.affiliation: Department of Neurosurgery, Binzhou Medical University Hospital, Binzhou, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Geng
authors.affiliation: Department of Neurosurgery, Binzhou Medical University Hospital, Binzhou, China.
authors.forename: Lixin
authors.initials: L
authors.lastname: Ma
authors.affiliation: Department of Neurosurgery, Binzhou Medical University Hospital, Binzhou, China. Electronic address: lizefu163@163.com.
authors.forename: Zefu
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Neurosurgery, Binzhou Medical University Hospital, Binzhou, China.
authors.forename: Zhenzhu
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Neurosurgery, Binzhou Medical University Hospital, Binzhou, China.
authors.forename: Jianmin
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Neurosurgery, Binzhou Medical University Hospital, Binzhou, China.
authors.forename: Meng
authors.initials: M
authors.lastname: Li
authors.affiliation: Department of Neurosurgery, Binzhou Medical University Hospital, Binzhou, China.
authors.forename: Qingbo
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department of Neurosurgery, Binzhou Medical University Hospital, Binzhou, China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Department of Neurosurgery, Binzhou Medical University Hospital, Binzhou, China.
authors.forename: Qikai
authors.initials: Q
authors.lastname: Sun
mesh_terms: D000236:Adenoma / Q000188:drug therapy* / Q000473:pathology / Q000601:surgery; D000328:Adult; D000368:Aged; D000818:Animals; D001343:Autophagy / Q000187:drug effects* / Q000502:physiology; D001971:Bromocriptine / Q000494:pharmacology / Q000627:therapeutic use*; D016923:Cell Death / Q000187:drug effects / Q000502:physiology; D045744:Cell Line, Tumor; D004305:Dose-Response Relationship, Drug; D005260:Female; D006727:Hormone Antagonists / Q000494:pharmacology / Q000627:therapeutic use; D006801:Humans; D008297:Male; D008875:Middle Aged; D010911:Pituitary Neoplasms / Q000188:drug therapy* / Q000473:pathology / Q000601:surgery; D051381:Rats
chemical_list: D006727:Hormone Antagonists; D001971:Bromocriptine
keywords: Autophagic cell death; Autophagy; Bromocriptine; Cell cycle arrest; Prolactinoma