Disease relevance of GREB1

• PDZK1 and GREB1 are estrogen-regulated genes expressed in hormone-responsive breast cancer [1].
• METHODS: We investigated the effects of androgens on GREB1 expression and its role in androgen-dependent prostate cancer growth [2].
• RESULTS: Real-time PCR demonstrated high level GREB1 expression in benign prostatic hypertrophy (BPH), localized prostate cancer (L-PCa), and hormone refractory prostate cancer (HR-PCa) [2].
• Changes in the subcellular distribution and quantification of glutathione were studied with electron microscopic immunogold cytochemistry in Zucchini yellow mosaic virus (ZYMV)-infected Styrian pumpkin plants (Cucurbita pepo L. ssp. pepo var. styriaca Greb.) two weeks after inoculation [3].

High impact information on GREB1

• GREB1 was also induced by beta-estradiol in the ER-positive endometrial cell line ECC-1 [1].
• These three cDNAs of GREB1 shared extensive sequences through the open reading frame but had divergent 5' untranslated regions, indicating the possibility of multiple promoters regulated by beta-estradiol [1].
• Treatment with cycloheximide indicated that ER directly controls GREB1 expression [1].
• Estradiol-17beta (E2)-induced gene expression of pS2 and GREB1 was impaired by 50-75% after 24-72 h of E2 treatment in PR-transfected cells [4].
• CONCLUSION: Our study suggests that GREB1 and HPCAL1 are candidate hypertension-susceptibility genes in the Japanese general population and supports previous studies that also identified hypertension-related loci in this narrow region [5].

Chemical compound and disease context of GREB1

• GREB1 is a novel androgen-regulated gene required for prostate cancer growth [2].

Biological context of GREB1

• Suppression of GREB1 by RNA interference blocked androgen-stimulated LNCaP cell proliferation [2].
• GREB1 is expressed in the prostate and its putative promoter contains potential androgen receptor (AR) response elements [2].
• Electronmicroscopic immunogold cytochemistry was used to investigate the cellular and subcellular distribution of glutathione in root and leaf cells of Styrian pumpkin (Cucurbita pepo L. subsp. pepo var. styriaca Greb.) plants [6].

Associations of GREB1 with chemical compounds

• Quantitative real-time PCR assays confirmed that in all three cell lines, GREB 1 was induced by E2, but not by the antiestrogens tamoxifen (TAM) or ICI 182,780 [7].
• Long-range histone acetylation, centered on the three ERE motifs and the GREB1 core promoters, was observed in response to estrogen but not to tamoxifen [8].

Physical interactions of GREB1

• AR binding to the GREB1 promoter was confirmed by chromatin immunoprecipitation (ChIP) assays [2].

Regulatory relationships of GREB1

• Androgen treatment of AR-positive prostate cancer cells induced dose-dependent GREB1 expression, which was blocked by anti-androgens [2].

Other interactions of GREB1

• GREB 1 expression level was strongly correlated with ER alpha positivity in 39 breast cancer cell lines of known ER alpha expression status [7].
• GREB 1 induction by E2 was rapid (7.3 fold by 2 h for MCF-7) and mirrored the fraction of cells entering S-phase when released from an estrogen deprivation induced cell arrest [7].

References