To block angiogenesis-mediated tumour growth and metastasis, several natural angiogenic inhibitors, including thrombospondin; interferon; matrix metalloproteinase inhibitors; synthetic angiogenesis inhibitors such as protease inhibitors; anti-adhesive peptides; and pharmacologic inhibitors, including AGM 1470/TNP 470; and thalidomide, have been reported in addition to tumour derived inhibitor angiostatin and endostatin. This evidence concerns the gene PLG and neoplasm.