title: [The effects of tamoxifen on human hepatocellular carcinoma cell proliferation and transforming growth factor-beta1 expression].
abstract: OBJECTIVE
  Tamoxifen has been tried in patients with hepatocellular carcinoma (HCC), however, its inhibitory mechanism remains unknown. In this study, we evaluated the effects of tamoxifen on HCC cell growth and the expression of transforming growth factor-beta1 (TGF-beta1) which had been known as an important cytokine in growth of HCC.
  
  
  METHODS
  Hep 3B cells were cultivated in estrogen free media with 0.1 micro M, 0.5 micro M, 1 micro M, 5 micro M, and 10 micro M of tamoxifen for 6 days. Viable cells were counted daily and the TGF-beta1 concentrations in supernatant were measured by ELISA method.
  
  
  RESULTS
  The number of viable HCC cells increased rather significantly after the treatment of tamoxifen of lower concentration (0.1micro M) compared with that of the control (2.59x10(7) vs. 1.97x107; p<0.05). As the concentration of treated tamoxifen was higher, the number of viable HCC cells became gradually less, resulting in the significant decrease of it at the highest concentration (10micro M) compared with that of the control (1.40x10(7) vs. 1.97x10(7); p<0.05). TGF-beta1 concentration in supernatant of tamoxifen-treated samples was significantly decreased compared with those of controls, regardless of the amount of treated tamoxifen.
  
  
  CONCLUSIONS
  These results suggest that tamoxifen may suppress TGF-beta1 expression to an extent, although it has different effects on the proliferation of HCC cells, at the various concentrations of this agent in vitro. Such effects of tamoxifen on TGF-beta1 expression may inhibit the growth and progression of HCCs over-expressing TGF-beta1 in vivo.
authors.affiliation: Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Jung Woo
authors.initials: JW
authors.lastname: Shin
authors.forename: Young-Hwa
authors.initials: YH
authors.lastname: Chung
authors.forename: Moo In
authors.initials: MI
authors.lastname: Park
authors.forename: Jeong A
authors.initials: JA
authors.lastname: Kim
authors.forename: Min Hee
authors.initials: MH
authors.lastname: Choi
authors.forename: Yoon Jung
authors.initials: YJ
authors.lastname: Lee
authors.forename: Soo Hyung
authors.initials: SH
authors.lastname: Ryu
authors.forename: Neung Hwa
authors.initials: NH
authors.lastname: Park
authors.forename: Han Chu
authors.initials: HC
authors.lastname: Lee
authors.forename: Yung Sang
authors.initials: YS
authors.lastname: Lee
authors.forename: Dong Jin
authors.initials: DJ
authors.lastname: Suh
authors.forename: Eun Sil
authors.initials: ES
authors.lastname: Yu
mesh_terms: D018931:Antineoplastic Agents, Hormonal / Q000494:pharmacology*; D006528:Carcinoma, Hepatocellular / Q000378:metabolism* / Q000473:pathology; D002455:Cell Division / Q000187:drug effects; D045744:Cell Line, Tumor / Q000378:metabolism; D006801:Humans; D008113:Liver Neoplasms / Q000378:metabolism* / Q000473:pathology; D013629:Tamoxifen / Q000494:pharmacology*; D016212:Transforming Growth Factor beta / Q000096:biosynthesis*; D053773:Transforming Growth Factor beta1
chemical_list: D018931:Antineoplastic Agents, Hormonal; C508960:TGFB1 protein, human; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; D013629:Tamoxifen