Treatment of angiogenesis disorders

A method for identifying a gene that regulates metastatic cancer colonization of a body tissue, comprising

• a) introducing one or more DNA molecules that encode a protein into a population of starting cancer cells to generate a population of engineered cancer cells, the population of starting cancer cells being obtained according to a process comprising performing serial rounds of transplantation, isolation, and repeat transplantation of a population of labeled or unlabeled cancer cells into a living tissue;
• b) transplanting said population of engineered cancer cells into a tissue of the body;
• c) isolating transplanted cells to obtain a population of isolated cancer cells;
• and
• d) assessing the quantity of the protein or of a nucleic acid encoding the protein in the population of isolated cancer cells,
• wherein an increase in the quantity of said protein or of the nucleic acid in the population of isolated cells relative to its quantity prior to transplantation indicates that the protein is required for metastatic colonization of said tissue.