title: Involvement of Bcl-2, Src, and ERα in gossypol-mediated growth inhibition and apoptosis in human uterine leiomyoma and myometrial cells.
abstract: OBJECTIVE
  to investigate the effect of gossypol on the growth of cultured human uterine leiomyoma and myometrial cells, the level of Bcl-2 and the activity of Src and estrogen receptor (ERα).
  
  
  METHODS
  human uterine leiomyoma and adjacent normal myometrial cells were cultured in vitro. Both cell types were treated with a graded concentration of gossypol. Cell viability was assayed using CCK-8. Morphological change was observed with optical and electronic microscopy. Apoptosis was evaluated using TUNEL assay. Levels of Bcl-2, ERα and Src were analyzed using Western blotting.
  
  
  RESULTS
  gossypol significantly inhibited growth and promoted apoptosis in cultured human uterine leiomyoma cells with the IC(50) value and its corresponding 95% confidence intervals (CI) of 6.5 (4.0-10.5), 9.0 (4.9-16.5), and 7.5 (4.0-14.1) micromol/L at 20, 40, and 60 h, respectively. Gossypol exerted inhibitory effects on the myometrial cells with the IC(50) value and its 95% CI of 49.1 (28.3-85.0), 14.5 (7.7-27.4), and 2.6 (1.2-5.6) micromol/L at 20, 40, and 60 h, respectively. Compared with control, gossypol 0.1-3.0 micromol/L markedly decreased the protein expression of Bcl-2 (P<0.05) in both leiomyoma and myometrial cells in a concentration-dependent manner, and significantly suppressed the level of phospho-Tyr416Src (P<0.05) in both cell types at 3.0 micromol/L without obvious alteration of c-Src and phospho-Tyr527Src levels (P>0.05). In addition, gossypol markedly reduced both the expression of ERα (P<0.05) at the low concentration of 0.1 micromol/L in the myometrial cells and the level of phospho-ser167ERα (P<0.05) at the high concentration of 3.0 μmol/L in the leiomyoma cells.
  
  
  CONCLUSIONS
  gossypol inhibits proliferation and induces apoptosis in human uterine leiomyoma and myometrial cells. It is likely that the mechanisms of action involve reducing the protein level of Bcl-2 and the activity of Src and ERα.
authors.affiliation: Department of Reproductive Pharmacology, NPFPC Key Laboratory of Contraceptives and Devices, Shanghai Institute of Planned Parenthood Research, Shanghai 200032, China. zhuyan@sippr.org
authors.forename: Yan
authors.initials: Y
authors.lastname: ZHU
authors.forename: Shu-wu
authors.initials: SW
authors.lastname: XIE
authors.forename: Jian-feng
authors.initials: JF
authors.lastname: ZHANG
authors.forename: Ting-ting
authors.initials: TT
authors.lastname: ZHANG
authors.forename: Jie-yun
authors.initials: JY
authors.lastname: ZHOU
authors.forename: Yang
authors.initials: Y
authors.lastname: CAO
authors.forename: Lin
authors.initials: L
authors.lastname: CAO
mesh_terms: D000328:Adult; D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3 / Q000378:metabolism; D049109:Cell Proliferation / Q000187:drug effects*; D002470:Cell Survival; D004305:Dose-Response Relationship, Drug; D047628:Estrogen Receptor alpha / Q000502:physiology*; D005260:Female; D006072:Gossypol / Q000494:pharmacology*; D006801:Humans; D020287:In Situ Nick-End Labeling; D007889:Leiomyoma / Q000378:metabolism* / Q000473:pathology; D009215:Myometrium / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000502:physiology*; D014407:Tumor Cells, Cultured; D014594:Uterine Neoplasms / Q000378:metabolism* / Q000473:pathology; D019061:src-Family Kinases / Q000502:physiology*
chemical_list: D047628:Estrogen Receptor alpha; D019253:Proto-Oncogene Proteins c-bcl-2; D019061:src-Family Kinases; D053148:Caspase 3; D006072:Gossypol