Immunohistochemical analysis of FRA-1 in benign and malignant breast tissues. Paraffin sections from hyperlastic and neoplasic breast tissues were analyzed by immunohistochemistry using antibodies raised against a specific FRA-1 peptide.A) Nuclear and cytoplasmic staining in a typical breast hyperplasia (200 ×). B) Immunostaining of a breast fibroadenoma (200 ×) showing nuclear and cytoplasmic staining. C) and D) Immunostaining of an atypical hyperplasia at two different magnification (100 ×) and (200 ×) respectively: the staining is present in the majority of the nuclei and is weakly present in the cytoplasm. E) Immunostaining of a ductal in situ breast carcinoma (400 ×): the immunostaining is restricted to the nucleus and weakly present in the cytoplasm, but it is not present in all the cells. F) Immunostaining of a lobular carcinoma (400 ×): the immunostaining is restricted to the nucleus, and is present in all malignant cells.