Sternlicht and Barsky (1997) suggest that PAI-1 does not contribute to the anti-invasive phenotype of MEs or, conversely, to a highly invasive and metastatic phenotype of tumour cells. In fact, PAI-1 has been correlated directly with uPA expression and poor prognosis in breast cancer (Schmitt et al, 1997). Here, PLAU is linked to Meckel syndrome, type 1.