Novel models of cancer-related anemia in mice inoculated with IL-6-producing tumor cells.

We established models of cancer-related anemia in mice from subcutaneous inoculation of two IL-6-producing cancer cell lines, human lung cancer cell line LC-06-JCK and murine colon26 clone 5 colon cancer cells. In both models, elevated levels of IL-6 were detected in sera and hemoglobin levels significantly decreased compared with non-tumor-bearing mice. In the LC-06-JCK model, serum albumin levels also decreased with elevated levels of human IL-6 in sera. On the other hand, serum levels of EPO increased, although anemia developed and did not improve. The development of cancer-related anemia was prevented by the administration of a rat anti-mouse IL-6 receptor antibody, MR16-1, in the LC-06-JCK model. It is therefore suggested that IL-6 causes anemia independent of a reduction in EPO levels. Our preclinical models should be useful for exploring new modalities for the treatment of cancer-related anemia.