title: Estradiol agonists inhibit human LoVo colorectal-cancer cell proliferation and migration through p53.
abstract: OBJECTIVE
  To investigate the effects of 17β-estradiol via estrogen receptors (ER) or direct administration of ER agonists on human colorectal cancer.
  
  
  METHODS
  LoVo cells were established from the Bioresource Collection and Research Center and cultured in phenol red-free DMEM (Sigma, United States). To investigate the effects of E2 and/or ER selective agonists on cellular proliferation, LoVo colorectal cells were treated with E2 or ER-selective agonists for 24 h and 48 h and subjected to the MTT (Sigma) assay to find the concentration. And investigate the effects of E2 and/or ER selective agonists on cell used western immunoblotting to find out the diversification of signaling pathways. In order to observe motility and migration the wound healing assay and a transwell chamber (Neuro Probe) plate were tased. For a quantitative measure, we counted the number of migrating cells to the wound area post-wounding for 24 h. We further examined the cellular migration-regulating factors urokinase-type plasminogen activator (u-PA), tissue-type plasminogen activator (t-PA) and matrix metalloproteinase (MMP)-9 in human LoVo cells so gelatin zymography that we used and gelatinolytic activity was visualized by Coomassie blue staining. And these results are presented as means ± SE, and statistical comparisons were made using Student's t-test.
  
  
  RESULTS
  The structure was first compared with E2 and ER agonists. We then treated the LoVo cells with E2 and ER agonists (10(-8) mol/L) for 24 h and 48 h and subsequently measured the cell viability using MTT assay. Our results showed that treatment with 17β-estradiol and/or ER agonists in human LoVo colorectal cancer cells activated p53 and then up-regulated p21 and p27 protein levels, subsequently inhibiting the downstream target gene, cyclin D1, which regulates cell proliferation. Taken together, our findings demonstrate the anti-tumorigenesis effects of 17β-estradiol and/or ER agonists and suggest that these compounds may prove to be a potential alternative therapy in the treatment of human colorectal cancer. These results demonstrate that 17β-estradiol and/or ER agonists downregulate migration-related proteins through the p53 signaling pathway in human LoVo colorectal cancer cells. These findings suggest that p53 plays a critical role in the 17β-estradiol and/or ER agonist-mediated protective activity against colorectal cancer progression. In addition, 17β-estradiol and/or ER agonists dramatically inhibited cell migration and reduced the expression of u-PA, t-PA and MMP-9 as well as MMP-2/9 activity in LoVo cells, which regulate cell metastasis. Moreover, we observed that pretreatment with a p53 inhibitor significantly blocked the anti-migration effects of E2 and/or ER agonists on LoVo cells. That E2 and/or ER agonists may impair LoVo cell migration by modulating migration-related factors via the p53 tumor suppressor gene.
  
  
  CONCLUSIONS
  Direct ER treatment may prove to be an attractive alternative therapy in the treatment of human colorectal tumors in the future.
authors.affiliation: Hsi-Hsien Hsu, Division of Colorectal Surgery, Mackay Memorial Hospital, Taipei 251, Taiwan.
authors.forename: Hsi-Hsien
authors.initials: HH
authors.lastname: Hsu
authors.affiliation: Hsi-Hsien Hsu, Division of Colorectal Surgery, Mackay Memorial Hospital, Taipei 251, Taiwan.
authors.forename: Wei-Wen
authors.initials: WW
authors.lastname: Kuo
authors.affiliation: Hsi-Hsien Hsu, Division of Colorectal Surgery, Mackay Memorial Hospital, Taipei 251, Taiwan.
authors.forename: Da-Tong
authors.initials: DT
authors.lastname: Ju
authors.affiliation: Hsi-Hsien Hsu, Division of Colorectal Surgery, Mackay Memorial Hospital, Taipei 251, Taiwan.
authors.forename: Yu-Lan
authors.initials: YL
authors.lastname: Yeh
authors.affiliation: Hsi-Hsien Hsu, Division of Colorectal Surgery, Mackay Memorial Hospital, Taipei 251, Taiwan.
authors.forename: Chuan-Chou
authors.initials: CC
authors.lastname: Tu
authors.affiliation: Hsi-Hsien Hsu, Division of Colorectal Surgery, Mackay Memorial Hospital, Taipei 251, Taiwan.
authors.forename: Ying-Lan
authors.initials: YL
authors.lastname: Tsai
authors.affiliation: Hsi-Hsien Hsu, Division of Colorectal Surgery, Mackay Memorial Hospital, Taipei 251, Taiwan.
authors.forename: Chia-Yao
authors.initials: CY
authors.lastname: Shen
authors.affiliation: Hsi-Hsien Hsu, Division of Colorectal Surgery, Mackay Memorial Hospital, Taipei 251, Taiwan.
authors.forename: Sheng-Huang
authors.initials: SH
authors.lastname: Chang
authors.affiliation: Hsi-Hsien Hsu, Division of Colorectal Surgery, Mackay Memorial Hospital, Taipei 251, Taiwan.
authors.forename: Li-Chin
authors.initials: LC
authors.lastname: Chung
authors.affiliation: Hsi-Hsien Hsu, Division of Colorectal Surgery, Mackay Memorial Hospital, Taipei 251, Taiwan.
authors.forename: Chih-Yang
authors.initials: CY
authors.lastname: Huang
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism* / Q000473:pathology; D018931:Antineoplastic Agents, Hormonal / Q000494:pharmacology*; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects*; D015179:Colorectal Neoplasms / Q000378:metabolism* / Q000473:pathology; D004305:Dose-Response Relationship, Drug; D004958:Estradiol / Q000494:pharmacology*; D004967:Estrogens / Q000494:pharmacology*; D006801:Humans; D009361:Neoplasm Invasiveness; D011960:Receptors, Estrogen / Q000187:drug effects* / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D013997:Time Factors; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*
chemical_list: D018931:Antineoplastic Agents, Hormonal; D004967:Estrogens; D011960:Receptors, Estrogen; C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53; D004958:Estradiol
keywords: Estrogen; Estrogen agonist; Estrogen receptors; Human colon cancer cell; p53