Skin Cancer in Australia – Can Increasing Melanin In Your Skin Protect You?
More people are diagnosed with skin cancer in Australia than any other cancer combined.
In fact, melanoma – a highly dangerous type of skin cancer is estimated to claim one life every hour. So what if you could lower your risk of skin cancer by changing the color of your skin? Ok, this is big , so let’s start with the science. Everyone has something in their skin called melanin, a biological pigment that gives us the color of our skin, hair, and eyes.
The cells in our epidermis that make this pigment are called melanocytes and everyone has the same number of them, but everyone’s melanocytes make different amounts of melanin, and different kinds. Melanin serves a few very important purposes besides giving your skin its color. When you’re outside, your skin is being exposed to the ultraviolet rays of the sun.
The UV radiation is just that radiation and prolonged exposure can damage the DNA of your skin cells. With enough damage, that DNA can start to malfunction and the life cycle of your skin cells is disrupted, potentially causing uncontrolled replication and leading to cancerous growths. Your body lookin’ out for you though and has a couple of defense mechanisms in place one of which is your melanocytes. Inside your melanocytes are little melanin-producing factories called melanosomes.
If the mitochondria are the powerhouse of the cell, the melanosome is the powerhouse of the melanocyte. And there are two kinds of melanin produced by these melanosomes eumelanin, a darker pigment, and pheomelanin, a light-colored pigment. Eumelanin blocks UV photons from damaging the skin, so those without a lot of it, people with lighter skin are at higher risk of sun damage. So when your skin is exposed to more sun, your melanocytes are ‘turned on’ to produce more of this UV-blocking melanin to protect your cells.
How much melanin and which kind your skin makes is controlled by your genes. That’s why some people’s skin tone deepens or is making more melanin when exposed to sunlight. Others can’t produce more than a certain amount of melanin, and so find their skin exposed to more damage resulting in sunburn. So, more melanin equals darker skin tone and equals more protection from the sun’s harmful rays.
The big takeaway from all this detail is that those with more melanin, particularly eumelanin, are at a decreased risk for skin cancer. And now, researchers have explored how that level of protection can be artificially induced for those who don’t have it naturally. It turns out that the melanosomes that produce the two different types of melanin have different pHs, and remember the melanosome is that little pigment making machine inside your melanocytes.
Eumelanin, the dark, highly protective pigment, is produced by melanosomes that are less acidic than the melanosomes that produce pheomelanin. So researchers have posited and now shown that they can actually change the relative amounts of which kind of melanin your melanosomes produce. Inhibiting a certain enzyme, called sAC, can make melanosome pH less acidic and allows those cells to produce more eumelanin meaning darker pigmentation and increased protection from skin cancer.
We’re still not exactly sure why pH influences what kind of melanin your melanosomes produce, and this is an area that researchers are hoping to explore further. It’s important to note that this is different from regulating melanin production by changing the way your genes are expressed, it’s not genetic editing. This new research could instead result in a pharmaceutical drug that induces pigment production potentially for use by populations vulnerable to skin cancer, or those with pigmentation conditions that they’d like to treat.
This is still in the very early stages though, being tested in mice and human skin cells in Petri dishes. It’s a long way away from practical applications in humans. Ok, so science is super cool. But the color of someone’s skin has been something that defines and often divides humans for millennia. So if it becomes possible for us to change that color in a very fundamental way for medical purposes, what does that mean for our conception of things like race? Would its use be ethical?
The authors of the study note at the very top of their research that skin pigmentation has not only health implications but also very important psychosocial ones – a reminder that science doesn’t happen in a vacuum and its results and takeaways go out into an imperfect world and that’s something we need to consider. What do you think about this research? Let us know in the comments below, and keep coming back to Seeker for all things science news. And, fun fact! The scientific word for sunburn is erythema solare.