Abstract
Tumorigenicity refers to the ability of cultured cells to develop viable tumors in immune-deficient animals. The goal of this protocol is to illustrate tumorigenicity assay by subcutaneous tumor-cell-transplantation in nude mice. Target cells are transplanted to 6-week-old nude mice subcutaneously and the tumor growth is monitored over a period of observation or treatment. When tumor grows to a pre-determined size or by the end of the limited period, the nude mice will be euthanatized and the xenograft will be removed for further examination.