Influence of hormones on tumor growth, cell kinetics, estrogen receptor and insulin-like growth factor-I-related protein of human breast cancer (MCF-7) cells transplanted in nude mice.
The influence of estrogens and tamoxifen on estrogen receptor (ER)-positive human breast cancer (MCF-7) cells transplanted into athymic nude mice was investigated. The mice were divided into the following three groups: (1) an E2 group with mice receiving 17 beta-estradiol dipropionate; (2) a TAM group with mice receiving tamoxifen; (3) a control group with mice given no hormone. (1) Tumor growth was significantly increased in the E2 group, but significantly decreased in the TAM group compared to control; (2) the tumor contents of insulin-like growth factor-I (IGF-I) and the rate of IGF-I-positive cells were significantly lower in the E2 group, but significantly higher in the TAM groups compared to control; (3) the IGF-I-positive cell rates were in significant inverse correlation with the [3H]thymidine-labeled cell rates in the E2, TAM and control groups. Thus, the tumor contents of IGF-I and the rate of IGF-I-positive cells were inversely correlated to the tumor growth and the [3H]thymidine-labeled cell rate in this in vivo study, although IGF-I is known to be a mitogen for breast cancer cells in vitro. Further studies are necessary to answer the questions as to the in vivo roles of immunoreactive IGF-I in ER-positive breast cancer.
Noguchi
M
M
Operation Center, Kanazawa University Hospital, School of Medicine, Japan.
Thomas
M
M
Koyasaki
N
N
Ohta
N
N
Taniya
T
T
Kitagawa
H
H
Miyazaki
I
I
Mizukami
Y
Y
D000818:Animals; D001943:Breast Neoplasms / Q000737:chemistry / Q000473:pathology*; D002453:Cell Cycle / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D004273:DNA, Neoplasm / Q000032:analysis; D004958:Estradiol / Q000031:analogs & derivatives* / Q000494:pharmacology; D004967:Estrogens; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects*; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D009363:Neoplasm Proteins / Q000096:biosynthesis*; D009368:Neoplasm Transplantation; D009376:Neoplasms, Hormone-Dependent / Q000737:chemistry / Q000473:pathology*; D011960:Receptors, Estrogen / Q000096:biosynthesis*; D011980:Receptors, Progesterone / Q000096:biosynthesis*; D013629:Tamoxifen / Q000494:pharmacology*; D015854:Up-Regulation / Q000187:drug effects
D004273:DNA, Neoplasm; D004967:Estrogens; D009363:Neoplasm Proteins; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; D013629:Tamoxifen; D004958:Estradiol; C023482:estradiol dipropionate