CLOCK and neoplasm: DCs exhibit a rhythmic migration to the tumor-draining lymph nodes in a manner that is dependent on the diurnal expression of the co-stimulatory molecule CD80, which in turn governs the circadian rhythmic response of tumor antigen-specific CD8+ T cells.244 However, the researchers did not further investigate the correlation between the circadian expression of CD80 and clock genes, which warrants further investigation.