We found overexpression of PROX1 protein in high-grade compared with low-grade gliomas and demonstrated that the percentage of tumour cells expressing PROX1 correlated with the malignancy grade of the tumour, which prompted further studies with focus on the expression of PROX1 in relation to clinical parameters and patient survival (Elsir et al, 2010). This evidence concerns the gene PROX1 and glioma.