Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:2.7.12.2 (
MEK
)
18,161
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The mitogen-activated protein kinase (MAPK) cascade, which includes MAPK,
MAP kinase kinase
(
MAPKK
) and Raf-l, is involved in the signal transduction of growth factor receptors. We found that the MAPK and Raf-l proteins are increased in human breast cancer. Activated
MAPKK
was also observed. We then investigated whether the MAPK cascade is activated when 7,12-dimethylbenz(a) anthracene (DMBA)-induced rat mammary cancer is treated with 17 beta-estradiol (
E-2
). Ovariectomy suppressed MAPK expression in tumors, and
E-2
administration induced the activation of MAPK in ovariectomized rats. We also investigated the effects of tamoxifen (TAM) on proliferation and the MAPK cascade in DMBA-induced rat mammary cancers. Although tumor size was reduced significantly by TAM, the expression of the MAPK and Raf-l proteins did not decrease. Additionally, MAPK and Raf-l protein expression increased in tumors of ovariectomized rats given TAM, despite a reduction in the size of the tumors. These results suggest that the activated MAPK cascade is important in human breast cancer, and is an important mechanism in the estrogen-dependent growth of DMBA-induced rat mammary cancer. TAM shows
E-2
-antagonistic effects on tumor proliferation, and
E-2
-agonistic effects on the MAPK cascade.
...
PMID:Effects of estrogen and tamoxifen on the MAP kinase cascade in experimental rat breast cancer. 2152 50
