Immunofluorescent localization of C-erbB-2 oncoprotein in breast cancer: a preliminary study

Monoclonal antibody CIBCgp185 of IgG2a isotype has been generated against C-erbB-2 oncoprotein using BT474 breast carcinoma cell line as immunogen. Earlier studies have revealed that this MAb has potential application as diagnostic tool in the detection of breast cancers overexpressing C-erbB-2. In the present study, the reactivity pattern of this MAb was studied on frozen sections of 28 malignant and 15 normal breast tissues and on cultured mammary tumor cell lines by indirect immunofluorescent staining. Results indicated that gp185C-erbB-2 was overexpressed in 6 malignant specimens, indicating correlation with immunohistochemical analysis studied previously. These results indicate that immunofluorescence might also be used to study C-erbB-2 overexpression in breast cancers and could serve as a confirmatory test for IHC. However, further studies with large number of cases are needed to confirm these results.