Moreover, recent studies have suggested that Prox1 may also play a role in tumor development and progression as altered PROX1 expression (on both transcript and protein level) has been found in a variety of human cancers, such as brain tumors, pancreatic cancer, colon cancer, liver carcinoma, Kaposi sarcoma and small cell lung carcinoma [24-31]. This evidence concerns the gene PROX1 and small cell lung carcinoma.