Presence of genetic alterations in microdissected stroma of human colon and breast cancers

We show by laser-assisted microdissection that frequent genetic alterations in non-hereditary invasive human colon and breast cancers (loss of heteroz ygosity and TP53 mutations) occur not only in the neoplastic epithelial cel ls, but also in the adjacent fibroblastic tumor stroma and that both compon ents can share clonal features. Tumor cell-mesenchyme transitions are among the possible explanations for these findings.