Although all uPAR-expressing cells were eradicated by this treatment, the reduction of tumor size was only moderate and transient due to the combined small penetration range of 177Lu β-radiation (<2 mm) and the confined expression of uPAR only at the periphery of the tumor comprising only 10% of the total HT-29 cancer cells in the tumor lesion [165]. This evidence concerns the gene PLAUR and neoplasm.