In a world where things seem to change overnight, melanin seems to stay essentially the same for more than 160 million years, a new study has found. Melanin is the biological pigment that determines an animal’s color, and is currently not very well understood. In the new study, scientists have found that a type of melanin called eumelanin from a Jurassic-era mollusk produces a signature when optically excited that is nearly identical to that of the optically excited eumelanin from its modern counterpart,Sepia officinalis, or the common cuttlefish. Because melanin survives so long, an analysis of the melanin from old cancerous tissue samples could give researchers a useful tool for predicting the spread of melanoma skin cancer in humans.
The researchers, Mary Jane Simpson, et al., led by Professor Warren S. Warren at Duke University in Durham, North Carolina, have published their paper on their analysis of Jurassic-aged eumelanin in a recent issue of The Journal of Physical Chemistry Letters.
“Melanoma is a particularly bad cancer if it metastasizes,” Warren told Phys.org. “Unfortunately, the ‘gold standard’ of conventional diagnostic techniques (essentially, excision followed by pathology) does not do a very good job of predicting which diagnosed cancers are likely to spread. So, how do you fix a bad gold standard for a bad disease?
“The best answer is retrospective studies—looking at decades-old specimens from patients, where you know the outcome—and trying to find systematic differences. That is impossible with most pathology methods because the tissue degrades. Our results show that it is possible with melanin-based diagnostics, since the melanin easily survives that long.”
Read more at: Phys.org