[BRCA1 selectively regulates the expression of progesterone receptor A in sporadic invasive ductal breast carcinoma].

OBJECTIVE

To investigate the expression level of BRCA1, progesterone receptor A (PRA) and B (PRB) in tissue of sporadic invasive ductal breast carcinoma and further statistically analyze the BRCA1 effects on the expression rates of PRA and PRB.

METHODS

Sixty-eight cases of adenosis of breast and sporadic invasive ductal breast carcinoma were selected. The corresponding paraffin-embodied tissues were collected from the archive of Department of Pathology, Nanfang Hospital. The expressions level of BRCA1, PRA and PRB were detected by immunohistochemistry. Wilcoxon two-sample test was used to analyze the differential expression of BRCA1 between adenosis and sporadic invasive ductal breast carcinoma. Chi-square test was used to analyze the effects of BRCA1 on the PRA or PRB expression rate. P value < 0.05 was considered statistically significant.

RESULTS

(1) In invasive sporadic ductal breast carcinoma, the positive rate of BRCA1 expression of 60.29% (41/68) was lower than the positive rate of BRCA1 expression at 85.30% (58/68) in adenosis of breast. And the difference of BRCA1 expression between two groups was statistically significant (P < 0.01); (2) In invasive sporadic ductal breast carcinoma, the positive rate of PRA expression for negative BRCA1 expression samples was 81.48% (22/27) and it was higher than the positive rate of PRA expression at 53.66% (22/47) for positive BRCA1 expression samples. And the difference of PRA expression rates between two groups was statistically significant (P < 0.05). It indicated that the expression of BRCA1 affected the expression rate of PRA; In invasive sporadic ductal breast carcinoma, the PRB expression rates between positive and negative BRCA1 expression samples were not statistically significant (P > 0.05). It indicated that BRCA1 had no effect upon the expression rate of PRB.

CONCLUSION

In sporadic breast carcinoma, a negative expression of BRCA1 is selectively associated with a higher expression rate of PRA rather than PRB. Thus BRCA1 selectively regulates the expression of PRA in sporadic breast carcinoma.