Bio-luminescent Imaging and Characterization of Organ-Specific Metastasis of Human Cancer in NOD/SCID Mice

Many clinical evidences demonstrate that the sites of distant metastasis are not random and certain malignant tumors show a tendency to develop metastases in specific organs (e.g., brain, liver, and lungs). However, an appropriate animal model to characterize the metastatic nature of transplantable human cancer cell lines has not been reported well. Recent advances in bio-luminescent imaging (BLI) technologies have facilitated the quantitative analysis of various cellular processes in vivo. To visualize the fate of tumor progression in the living mice, we are constructing a luciferaseexpressing human cancer cell library (including melanoma, colon, breast, and prostate cancer). Herein we demonstrate that the BLI technology in couple with a fine ultrasonic guidance realizes cancer cell-type dependent metastasis to the specific organs. For example, some melanoma cell lines showed frequent metastasis to brain, lungs, and lymph nodes in the mouse model. Notably, reflecting the clinical features of melanoma, breast, and prostate cancer, some of the cell lines showed preferential metastasis to the brain. Moreover, these cellular resources for BLI allow a high throughput screening for potential anti-cancer drugs. Thus, this BLI-mediated additional strategy with the luciferase-expressing cancer cell resources should promote many translational studies for human cancer therapy.