Melanoma is the most deadly form of skin cancer due to its ability to spread rapidly to other organs. Brazilian researchers have already developed a peptide that appears to slow the growth and spread of melanoma, improving the survival rate of test mice.
Skin cancer is the most common a common type of cancerand although melanoma is responsible for only about one percent of these cases, it causes the majority of skin cancer deaths. This is because it is particularly susceptible to metastasis.
Previous studies have linked a protein called PLP2 to the lethality of melanoma – overexpression has been shown to increase its metastases, while blocking it inhibits growth and spread. In the new study, researchers developed a peptide called Rb4, which is derived from PLP2, and tested how well it works against melanoma.
In tests on melanoma cells cultured in the laboratory, those treated with Rb4 stopped replicating and formed clusters. It appears to act directly on tumors, increasing the expression of two molecules that are involved in tissue damage, and ultimately causing necrosis, a type of cell death that results from a lack of blood flow to the tissue.
In other tests, the team injected melanoma cells into mice, followed by a series of five Rb4 injections over 10 days. Tumor growth is delayed by up to 40 days in treated mice and significantly reduces the number of metastatic nodules found in the lungs of animals. Treatment also increased the group’s survival by more than 25 percent.
The researchers also noted that no side effects were observed in the treated mice. With the results seen, the team suggests that the peptide Rb4 may become a promising treatment for cancer with further development, which is carried out in the Brazilian biotechnology company ReceptaBio.
The study was published in the journal Scientific reports.