Light, in terms of our experiments, stimulates breast-cancer growth activity, and obviously this is due to the ability of light to shut off melatonin production.

Evidence is emerging that disruption of one's circadian clock is associated with cancer in humans, and that interference with internal timekeeping can tip the balance in favor of tumor development.

If the link between light exposure and cancer risk can be confirmed, it could have an immediate impact on the production and use of artificial lighting in this country. This might include lighting with a wavelength and intensity that does not disrupt melatonin levels and internal timekeeping.

We observed rapid growth comparable to that seen with administration of daytime blood samples, when tumor activity is particularly high.

Uncontrolled cell growth is the hallmark of cancer.

Preliminary evidence suggests that these compounds may have some biological activity in slowing the growth of bladder cancer cells.