IMMUNOHISTOCHEMICAL DISTRIBUTION OF A BREAST CANCER-ASSOCIATED GLYCOPROTEIN

The tissue distribution and specificity of a glycoprotein of M(r) 230 000 kDa which has previously been identified from breast carcinomas in culture and shown to be tumour-associated, has been assessed using a polyclonal antiserum. A wide range of tissues has been examined immuno histochemically. The tissue distribution of the glycoprotein show diff erences between normal, benign and malignant breast and other epitheli al tissues, and are clearly specific for epithelial cells. This glycop rotein as detected by the polyclonal antiserum P5252-2, was either abs ent or showed a minimal presence in normal breast tissues. Evidence of the expression of the glycoprotein in hyperplastic breast was observe d but was considerably less than that seen for carcinomas, for which 7 0% had greater than 50% of cells exhibiting reactivity with P5252-2. T here was no relationship with grade or node status. Similar striking d ifferences in glycoprotein expression between non-neoplastic and neopl astic tissue were observed for stomach, large intestine, thyroid and t o lesser extent ovary. The differences in the expression of this glyco protein between normal and malignant tissues is of obvious clinical an d pathological potential.