Circadian and seasonal rhythms in murine bone marrow colony-forming cells affect tolerance for the anticancer agent 4'-O-tetrahydropyranyladriamycin (THP).

The proliferative status of both bone marrow myeloid precursor cells (GM-CFUc) and stromal cells from the microenvironment are organized along circadian and circannual time scales in male B6D2F1 mice. Such temporal structure profoundly affects the in vitro susceptibility of myeloid precursors for the anticancer agent, 4'-O-tetrahydropyranyl adriamycin. These results account in part for the large-amplitude circadian rhythms that characterize host tolerance for chemotherapy. They also provide evidence that the time of bone marrow sampling from a donor may influence its engraftment into the recipient.