Expression of mucin and carbohydrate antigens in breast carcinoma: correlations with clinico-pathological and reproductive parameters

ISLA-LARRAIN M; DEMICHELIS S; CRESPO M; BARBERA A; TERRIER F; CRETÓN A; GIACOMI N; ABBA MC; SEGAL-EIRAS A; CROCE MV

Robison College, Cambridge, UK

Workshop; 9th International Workshop on Carcinoma-associated Mucins; 2007

British Associate for Cancer Research (BACR)

Objective: to study the relationship among different risk factors and the expresión of MUC1, MUC4 and carbohydrate antigens in breast simples. Materials and methods: breast samples from 257 cancer patients and 46 bening and normal samples were included. Clinical data were age, histological type, tumour size, metastatic nodes, disease stage, estrogen receptors (ERa), number of pregnancies and children and breast feeding. Standard immunohistochemistry was developed; monoclonal antibodies (MAbs) were: anti-Lewis x (KM380), sLewis x (KM93), Lewis y (C14) and Tn; anti-MUC1 VNTR MAbs: C595, HMFG2 and SM3 and two polyclonal antibodies: CT33, an anti-MUC1CT and an anti-MUC4.Multivariate statistical analysis was performed. Percentage of stained cells, intensity and pattern were analyzed; malignant tumours revealed that 196 were positive for at least one MAb studied, 141 for anti-MUC1VNTR and 103/141 (73%) were positive for at least one anti-carbohydrate antigen MAb; 80% expressed only one carbohydrate antigen studied being exclusively expressed Lewis x in 44%, Tn antigen in 22%, Lewis y in 20% and sLewis x in 14%. Thirty tumours out of 196 positives (15.3%) were negative for the three anti-MUC1VNTR MAbs; from the last group, 11/30 were positive for MUC4 (36%) and also expressed carbohydrate antigens. In malignant tumours, MUC1 was mainly detected with a non apical membrane and cytoplasmic reaction while bening and normal samples showed an apical membrane reaction. In all cases, Lewis x staining was strong while Tn epitope was mild and cytoplasmic; sLewis x and Lewis y expressed a cytoplasmic and membrane reaction. ERa was positive in 54% of malignant tumours. In breast cancer, a positive and significant correlation was found between lactation vs Tn, Lewis y, sLewis x and Lewis x; the number of children vs carbohydrate antigens and also between peptide and carbohydrate antigenic expression. Conclusion: tumour cell expression of MUC1, MUC4 and carbohydrate antigens is associated with reproductive factors in breast cancer.