Background & Aims: Breast cancer is the most common cancer in women. Nearly 50% of breast cancers are dependent to sex hormones, and the effects of these hormones are mediated by their binding to specific receptors. Also p53 protein is mutated in about half of cancers including breast cancer and high level of p53 protein is a common feature of many human malignant cancers. Given that T47D cell line has estrogen and progesterone receptor and p53 protein is product of tumor suppressor gene. This article was devoted to the effect of progesterone on p53 protein in T47D cell line.

Materials & Methods: The breast cancer T47D cell line were grown in 25cm² flasks in DMEM

with fetal bovine serum (FBS). Then cells were treated with different concentrations (1 nmol, 10 nmol and 20 nmol) of progesterone hormone. The level of proteins was measured by western blot method. Gene tool software was used for data analysis.

Results: There was no differences in p53 protein level in cells that were exposed to 1nmol of progesterone compared to the control group (P>0.05), but cells that were exposed to 10 and 20 nmol of progesterone treatment had lower level of p53 protein concentration than the control (P<0.01).

Conclusion: The result of this study showed that increased progesterone can reduce the level of p53 protein in T47D cell line. It seems progesterone with decreased level of p53 protein reduced accumulation of p53 protein in T47 cell line.

SOURCE: URMIA MED J 2014: 25(10): 960 ISSN: 1027-3727