Determination of 35 cell surface antigen levels in malignant pleural effusions identifies CD24 as a marker of disseminated tumor cells

Many targets have been identified in solid tumors for antibody therapy but it is less clear what surface antigens may be mostcommonly expressed on disseminated tumor cells. Using malignant pleural effusions as a source of disseminated tumor cells,we compared a panel of 35 antigens for their cancer specificity, antigen abundance and functional significance. These anti-gens have been previously implicated in cancer metastasis and fall into four categories: (i) cancer stem cell, (ii) epithelial-mesenchymal transition, (iii) metastatic signature of in vivo selection and (iv) tyrosine kinase receptors. We determined theantigen density of all 35 antigens on the cell surface by flow cytometry, which ranges from 3 3 10