Expression of CD44 spliced variants with both exons v9 and v10 in primary N(-)M(-) breast carcinomas correlates with metastasis

We analyzed the representation of CD44 isoforms with both exons v9 and v10 among CD44 total amount and also examined correlation between their expression, clinical parameters and survival. We used a semi-quantitative RT-PCR reaction and a panel of 25 normal breast specimens, 10 mammary fibroadenomas, 8 cystic samples and 52 primary breast tumors. CD44 expression level was statistically higher in malignant tumors than in normal breast tissues (p = 0.038) or in fibroadenomas (p = 0.047) and correlated with histological grading, p = 0.047. Ratios CD44 variants with both exons v9 and v10/ total CD44 were similar in normal breast tissues and fibroadenomas but lower in the cystic samples. In primary N(-)M(-) breast tumors, unfavourable outcome and relapse were correlated with low ratios.