ABSTRACT
CD44 is a family of transmembrane glycoproteins involved in cell-cell and cell-matrix interactions. Expression of CD44 isofonns (splice variants) has been shown to be associated with poor prognosis in several human cancers. We evaluated the expression patterns of the CD44 isofortn (CD 44 splice variant v6) in infiltrating ductal carcinoma of the breast by immunohistochemical and RT-PCR method. Paraffin embedded blocks from seventy-five cases of mastectomized samples were analyzed immunohistochemically using monoclonoal antibody against CD44v6. CD44v6 was detected in fifty-seven cases (76%) of the tumor samples. Adjacent normal myoepithelial cells and ductal epithelial cells revealed focal positive reaction to CD44v6. Thirtytwo cases (80.0%) with lymph nodal metastasis revealed overexpression of CD44v6 monoclonal antibody, but twenty-five cases (71.4%) without nodal metastasis also showed positive reaction to CD44v6 monoclonal antibody, and there is no statistically significant value. Other prognostic factors of infiltrating ductal carcinoma, such as tumor size, histologic grade and hormonal receptors did not show any significant correlation with CD44v6 expression. The RT-PCR studies for 9 cases of infiltrating ductal carcinoma showed the same band patterns both in the normal and tumor tissues. From the above results, it is concluded that the expression of CD44v6 is not a valuable prognostic marker of infiltrating ductal carcinoma of breast.