Growth response of colon cancer cell lines to selective estrogen receptor modulators.
BACKGROUND
The purpose of this study was to compare the "in vitro" effects of the selective estrogen receptor modulators, tamoxifen and raloxifene, on two human colon cancer cell lines.


METHODS
Serial concentrations (0.1, 1, 5 and 10 microM) of tamoxifen and raloxifene were used and evaluated for cell proliferation, viability and apoptosis in HCT8 and HCT116 cells.


RESULTS
Micromolar doses of raloxifene significantly reduced HCT116 and HCT8 cell proliferation. Tamoxifen (5 microM) strongly reduced HCT8 cell growth with minor effects on HCT116 cells. Raloxifene (10 microM) was lethal on both cell lines, while 10 microM tamoxifen caused lethality only in HCT8 cells. Five microM raloxifene reduced cell viability in HCT8 and HCT116 cells, while 5 microM tamoxifen halved only HCT8 cell viability. Raloxifene and tamoxifen did not induce apoptosis in the two cell lines.


CONCLUSIONS
Tamoxifen, and even more raloxifene, were effective in reducing HCT8 and HCT116 cell proliferation and viability, suggesting their potential application in the prevention and therapy of colorectal cancer.
Picariello
Lucia
L
Department of Clinical Physiopathology, University of Florence, Florence, Italy.
Fiorelli
Gianna
G
Martineti
Valentina
V
Tognarini
Isabella
I
Pampaloni
Barbara
B
Tonelli
Francesco
F
Brandi
Maria Luisa
ML
D017209:Apoptosis / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D015179:Colorectal Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D004958:Estradiol / Q000494:pharmacology; D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D006801:Humans; D008297:Male; D020849:Raloxifene Hydrochloride / Q000494:pharmacology*; D011960:Receptors, Estrogen / Q000096:biosynthesis; D020845:Selective Estrogen Receptor Modulators / Q000494:pharmacology*; D013629:Tamoxifen / Q000494:pharmacology*; D014407:Tumor Cells, Cultured
D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D011960:Receptors, Estrogen; D020845:Selective Estrogen Receptor Modulators; D013629:Tamoxifen; D020849:Raloxifene Hydrochloride; D004958:Estradiol