Although there are therapies to treat melanoma, the most aggressive form of skin cancer, no full remedy is currently available for the life-threatening disease.
A breakthrough made by Israeli scientists, however, has uncovered how this form of skin cancer spreads to other organs in the body, a discovery that may revolutionize the treatment of the disease.
In a study published in the journal Nature Cell Biology, scientists from the Tel Aviv University in Israel examined pathology samples of early melanoma from patients before the disease entered into the invasive stage.
They found that before melanoma spreads to other organs, the tumor sends out tiny vesicles, small cysts or blisters that contain molecules of microRNA. The vesicles induce changes in the dermis of the skin to prepare it to receive the cancer cells and transport them further.
"To our surprise we found changes in the morphology of the dermis — the inner layer of the skin — that had never before been reported," study researcher Carmit Levy said.
After unveiling the mechanism, the researchers went on to look for substances that can intervene with and stop the process at the earliest stages.
They found two chemicals: the SB202190, which inhibits the delivery of the vesicles from the tumor to the dermis, and the U0126, which blocks the morphological changes in the inner layer of the skin even after the vesicles have arrived.
With their capacity to stop the processes involved in the spread of melanoma, the chemical substances show promise as drug candidates for treating the condition. Levy said their finding is an important step that can pave the way for the development of a full remedy for the disease.
"Since the first interaction of melanoma cells with blood vessels occurs in the dermis, our data suggest an opportunity to block melanoma invasion by preventing the formation of the dermal tumor niche," the researchers wrote in their study, which was published online on Aug. 22.
Survival rates are relatively high if melanoma is caught in its early stages but it is often fatal once it has spread. Levy explained that the threat of the disease is not in the initial tumor that appears on the skin but in the metastasis when the tumor cells set off to colonize the vital organs of the body, such as the brain, liver, lungs and bones.
According to the Skin Cancer Foundation, melanoma kills one person every 52 minutes and diagnosed cases have been rising over the past three decades.
