Chronodisruption alter expression of tumorigenesis associated transcripts in mouse brain

Disturbances in natural daily light regulation, as frequently happen in modern life, may lead to the disruption of the circadian clock organization. Such chronodisruption had been associated with disturbances in cell cycle homeostasis and with malignancy. The International Agency for Research in Cancer (IARC) classified shift work that involves circadian disruption as possibly carcinogenic. Recently, I showed by microarray analysis that light pulse during the dark phase promptly affects transcription level of genes that directly control cell cycle progression in mouse brain. Here I specifically assess the microarray results with respect to transcripts that are associated with tumorigenesis. The analysis indicated that light promptly affects transcription level of a substantial number of genes that are associated with cell proliferation and tumorigenesis, as well as transcripts that control cell cycle progression. A considerable assembly of affected transcripts promotes cell proliferation. It includes tumor suppressors, oncogenes and genes that are involved in tumor growth and metastasis. The results suggest an association between light signal during the dark phase, obstruction of the cell cycle homeostasis and tumorigenesis.