Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1991 Dec;82(12):1436-41.
doi: 10.1111/j.1349-7006.1991.tb01817.x.

Estrogen receptor levels and tumor growth in a series of pituitary clonal cell lines in rats

N Fujimoto  1 , H Watanabe, A Ito, K Inoue
Affiliations

Estrogen receptor levels and tumor growth in a series of pituitary clonal cell lines in rats

N Fujimoto et al. Jpn J Cancer Res. 1991 Dec.

Abstract

Four kinds of in vitro clonal pituitary tumor cell lines named MtT/Se, MtT/SM, MtT/S and MtT/E, each of which shows different sensitivity to estrogen on proliferation, were inoculated into fat pad of ovariectomized rats and estrogen-loaded ovariectomized rats at 10(5) and 10(6) cells/site. They formed tumor with average latency ranging from 30 to 71 in ovariectomized rats and 13 to 63 days in estrogenized rats inoculated with 10(6) cells. MtT/Se was highly sensitive to estrogen for growth, and MtT/SM also grew well in estrogenized rats. With MtT/S and MtT/E, there was no significant shortening of average tumor latency in estrogenized rats. In vivo, the cytosolic estrogen receptor (ER) levels of MtT/Se, SM, S and E were measured to be 452 +/- 66, 370 +/- 115, 260 +/- 16 and 83 +/- 8 fmol/mg protein, respectively. In vitro, however, the lowest ER level was noted in MtT/Se. Histologically, all four tumors grown in rats were composed of homogeneous round cells, and MtT/Se contained particularly large nucleated cells. In MtT/E, the cells appeared to be changing into fibromatous cells. Three cell lines except MtT/E maintained the function of hormonal secretion in vivo as well as in vitro. Serum GH level was increased in rats with MtT/Se and MtT/S. Increased levels of both prolactin and growth hormone were measured in sera of rats with MtT/SM. Increases of hormones as well as tumor sizes were promoted by the estrogen.

PubMed Disclaimer

References

    1. ) Morel , Y. , Alvaladejo , V. , Bouvier , J. and Andre , J.Inhibition by 17β‐estradiol of the growth of the rat pituitary transplantable tumor MtF4 . Cancer Res. , 42 , 1492 – 1497 ( 1982. ). - PubMed
    1. ) Lloyd , R. V. , Landefled , T. D. , Maslar , I. and Frohman , L. A.Diethylstilbestrol inhibits tumor growth and prolactin production in rat pituitary tumors . Am. J. Pathol , 118 , 608 – 616 ( 1985. ). - PMC - PubMed
    1. ) Furth , J. , Clifton , K. H. , Gadsen , E. L. and Buffet , R. F.Dependent and autonomous mammotropic pituitary tumors in rats: their somatotropic features . Cancer Res. , 16 , 608 – 616 ( 1956. ). - PubMed
    1. ) Ueda , G. , Takizawa , S. , Moy , P. , Marolla , F. and Furth , J , Characterization of four transplantable mammotropic pituitary tumor variants in the rat . Cancer Res. , 28 , 1963 – 1975 ( 1968. ). - PubMed
    1. ) Lloyd , H. M , Meares , J. D. and Jacobi , J.Effects of the oestrogen and bromocriptine on in vivo secretion and mitosis in prolactin cells . Nature , 255 , 497 – 498 ( 1975. ). - PubMed

LinkOut - more resources