Comparison of N-(4-hydroxyphenyl)retinamide and all-trans-retinoic acid in the regulation of retinoid receptor-mediated gene expression in human breast cancer cell lines.
The activities of N-(4-hydroxyphenyl)retinamide [(4-HPR), Fenretinide] and all-trans-retinoic acid (RA) were determined for (a) the inhibition of cell proliferation; (b) the activation of human retinoid receptor-mediated target gene expression; (c) the inhibition of estradiol- and progesterone-induced gene activation in breast cancer cell lines; and (d) the regulation of the expression of tumor suppressor retinoblastoma protein. Similar to RA, both 4-HPR and its active metabolite N-(4-methoxyphenyl)retinamide (4-MPR) effectively impeded the growth of MCF7 and T-47D human breast cancer cell lines, except that 4-HPR also inhibited the proliferation of RA-resistant BT-20 cells. However, when tested in human recombinant retinoic acid receptor (RAR-alpha, RAR-beta, and RAR-gamma)-induced reporter gene assays, RA was much more potent (>100-fold) than either 4-HPR or 4-MPR. 4-HPR induced transcriptional activation through all three RAR subtypes at 1-10microM, while RA showed comparable activity at 10-100microM. Despite the apparent weak interaction at the RAR level, 4-HPR was comparable to RA in the inhibition of both estrogen receptor- and progesterone receptor-mediated transcriptional activation in MCF7 and T-47D cells, respectively. Moreover, similar to RA, 4-HPR and 4-MPR caused marked up-regulation of tumor suppressor retinoblastoma protein in both MCF7 and T-47D cells. Since RA and 4-HPR showed comparable activity in the inhibition of estrogen recptor- and progesterone receptor-induced gene transcription and in the stimulation of retinoblastoma protein expression in MCF7 and T-47D cells, the reduced RAR activation by 4-HPR may result in the lack of hepatic toxicity and therefore the improved therapeutic efficacy relative to RA.[1]References
- Comparison of N-(4-hydroxyphenyl)retinamide and all-trans-retinoic acid in the regulation of retinoid receptor-mediated gene expression in human breast cancer cell lines. Kazmi, S.M., Plante, R.K., Visconti, V., Lau, C.Y. Cancer Res. (1996) [Pubmed]
Annotations and hyperlinks in this abstract are from individual authors of WikiGenes or automatically generated by the WikiGenes Data Mining Engine. The abstract is from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.About WikiGenesOpen Access LicencePrivacy PolicyTerms of Useapsburg
