Luciferase activity as a marker of tumor burden and as an indicator of tumor response to antineoplastic therapy in vivo.

The gene encoding firefly luciferase has been used as a reporter gene for the study of gene function. The luciferase catalyzes its substrate and subsequently produces luminescence. In addition, it is not present in mammalian cells. We have therefore explored its use in monitoring the growth of tumors in vivo. The luciferase gene was transfected into two murine tumor lines, i.e. c162 melanoma and M109 lung carcinoma, and the luciferase activity associated with the cells was determined by a rapid chemiluminescent reaction. Luciferase activity was well-correlated with the number of tumor cells in vitro. Luciferase activity also correlated with the tumor burden in vivo, as well as with the effect of an adoptive T cell transfer therapy in the syngeneic C3H/HeN mice experimental tumor model. This assay offers the advantage of being quantitative, rapid, and reliable for the detection of tumor burden and for the evaluation of the effect of antineoplastic therapy.