Cellular Radiosensitivity and Tumor Radiation Response in the EMT6 Tumor Cell System

Abstract

The responses of experimental tumors and tumor cells to treatment with radiation or chemotherapeutic agents can be assayed in a number of ways. The response of solid tumors in situ can be examined using such endpoints as tumor cure or changes in tumor growth. Alternatively, the survival of the tumor cells can be assayed by removing them from the host after treatment and determining their clonogenicity in other animals or in cell culture. Cultured cells treated in vitro can be used to detail subtle features of the cellular response which are not amenable to analysis in vivo. However, the survival curves determined for tumor cells irradiated in situ generally differ from those observed when cells from the same tumor line are irradiated in vitro, primarily because of the presence of hypoxic, and therefore '1This investigation was supported by USPHS research grants CA-03353 and CA-10372 from the National Cancer Institute and training grant GM-00712 from the National Institute of General Medical Sciences.