Deadly Skin Cancer Trigger Identified, What’s Next?


2015-08-03 18:37

Scientists at Tel Aviv University have identified the trigger that causes the deadly skin cancer known as melanoma, a trigger that has been elusive until now. What is this discovery and what does it mean, especially since the rates of melanoma have been rising quickly over the past three decades in the United States?

Although melanoma makes up only 2 percent of skin cancer cases, it is the cause of nearly all deaths associated with this form of cancer. In 2015, an estimated 73,870 new cases of melanoma will be diagnosed and nearly 10,000 people are expected to succumb to the disease, according to the American Cancer Society.

At Tel Aviv University (TAU), Dr. Carmit Levy of the Department of Human Genetics and Biochemistry at TAU’s Sackler School of Medicine, along with a team of researchers from TAU, the Technion Institute of Technology, the Sheba Medical Center, The Hebrew University of Jerusalem, and the Institut Gustave Roussy, found the trigger that causes melanoma cancer cells to convert from non-invasive cells to aggressive killers. Even better, the experts identified the exact place where it happens.

Skin is composed of three layers: the epidermis, which is the top layer; the dermis, which is the thicker second layer; and the subcutaneous fat layer. Melanoma starts in the epidermis, and when it turns aggressive it invades the dermis. From there it gets into the blood or lymph vessels and can spread (metastasize) to other parts of the body.

Levy and her colleagues reported that melanoma cells move upward before they take a dive into the dermis. If those melanoma cells can be interrupted before their downward journey, the cancer might be eliminated. However, once the melanoma enters the bloodstream, the prognosis worsens and aggressive treatment is necessary.

To uncover what makes the melanoma cells go postal, the researchers gathered normal skin cells and melanoma cells, mixed them together, and conducted experiments to see how the cancer traveled. Levy noted that normal skin cells don’t travel, but that “when melanoma is situated at the top layer, a trigger sends it down to the dermis and then further down to invade blood vessels.”

Specifically, direct contact of melanoma cells with the epidermis triggers an invasion via Notch signaling, which switches on genes that cause the melanoma cells to become invasive. Therefore, scientists now know what they need to block to stop the cells from traveling and thus invading the bloodstream.

Levy explained that “there are many drugs in existence that can block the Notch signaling responsible for that transformation.” Research into their use should be forthcoming. She even suggested that one day people may be able to apply something to their skin to prevent melanoma from occurring.

For now, however, researchers will move forward to further develop this finding while melanoma continues to be a serious, often lethal disease. Everyone should still practice preventive measures, including

  • Use sunscreen properly and year round
  • Avoid use of tanning beds and salons
  • Seek shade whenever possible
  • Know your skin; check it regularly (e.g., once a month) for anything unusual such as changes in moles and/or new growths
  • Wear protective clothing
  • Avoid sunlight during the middle of the day

Also read how a flower may help stop melanoma

Sources
American Cancer Society
Tel Aviv University