Immunohistochemical analysis of medullary breast carcinoma autoantigens in different histological types of breast carcinomas

Abstract

Background: On the past decade a plethora of investigations were directed on identification of molecules involved in breast tumorogenesis, which could represent a powerful tool for monitoring, diagnostics and treatment of this disease. In current study we analyzed six previously identified medullary breast carcinoma autoantigens including LGALS3BP, RAD50, FAM50A, RBPJ, PABPC4, LRRFIP1 with cancer restricted serological profile in different histological types of breast cancer.

Methods: Semi-quantitative immunohistochemical analysis of 20 tissue samples including medullary breast carcinoma, invasive ductal carcinoma, invasive lobular carcinoma and non-cancerous tissues obtained from patients with fibrocystic disease (each of five) was performed using specifically generated polyclonal antibodies. Differences in expression patterns were evaluated considering percent of positively stained cells, insensitivity of staining and subcellular localization in cells of all tissue samples.

Results: All 6 antigens predominantly expressed in the most cells of all histological types of breast tumors and non-cancerous tissues with slight differences in intensity of staining and subcellular localization. The most significant differences in expression pattern were revealed for RAD50 and LGALS3BP in different histological types of breast cancer and for PABPC4 and FAM50A antigens in immune cells infiltrating breast tumors.

Conclusions: This pilot study made possible to select 4 antigens LGALS3BP, RAD50, PABPC4, and FAM50A as promising candidates for more comprehensive research as potential molecular markers for breast cancer diagnostics and therapy.

Virtual slides: The virtual slides' for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1860649350796892.

Figure 1

Immunohystochemical staining reaction of LGALS3BP, RAD50, and FAM50A MBC-associated antigens in breast cancer and non-cancerous tissues. Cancer cells of MBC and IDC demonstrated moderate to strong cytoplasmic and weak nuclear LGALS3BP staining, while in ILC samples weak cytoplasmic and moderate nuclear staining was observed. Strong positive LGALS3BP staining of cytoplasm and the apical part of normal epithelial cells was detected. Predominantly strong (3+) nuclear RAD50 staining in normal and cancer cells of MBC, IDC, and ILC was detected. Antigen FAM50A had moderate nuclear and weak cytoplasmic staining in NCT and tumor samples. C – cancer cells, L – lymphocytic infiltrate. Magnification 400x

Figure 2

Immunohystochemical staining reaction of RBPJ, PABPC4, and LRRFIP1 MBC-associated antigens in breast cancer and non-cancerous tissues. Antigen RBPJ had moderate nuclear and weak cytoplasmic staining of normal and cancer cells of NCT, MBC, and IDC, except for ILC samples which showed only moderate (2+) nuclear staining. Moderate to strong positive PABPC4 staining was detected in cytoplasm of normal and cancer cells of non-cancerous and cancer tissue samples. Cancer cells of IDC and ILC, and normal cells of non-cancerous tissues had moderate to strong nuclear and weak cytoplasmic LRRFIP1 staining, but in MBC moderate cytoplasmic LRRFIP1 staining was observed. C – cancer cells, L – lymphocytic infiltrate. Magnification 400x

Figure 3

Immunohistochemical staining of PABPC4 (A) and FAM50A (B) antigens in cells of lymphocytic infiltrate of medullary breast carcinoma. Both antigens showed more intensive staining of immune cells compared with cancer cells. Positive cytoplasmic PABPC4 staining was detected only in a part of immune cells. FAM50A showed preferentially nuclear staining in immune cells. Positively stained cells are indicated by arrows. C – cancer cells, L – lymphocytic infiltrate. Magnification 400x