COL18A1 and neoplasm: All of these data suggest that the generation of the anti-angiogenic factors in the tissue microenvironment is a common pathway for the protective MMPs to cancer cell growth and metastases, and may provide a clue to develop a new remedy against lung metastases by preventing from extravasation of tumour cells through modulation of tissue microenvironmental anti-angiogenic factors such as endostatin.