Researchers develop an antisense oligonucleotide ointment that may be useful as a topical treatment for skin cancer
Skin cancer is the most common cancer, accounting for one-third of all cancers worldwide. UV exposure puts us at risk for skin cancers by inactivating cell apoptosis. Cell apoptosis is regulated cell death that allows the body to eliminate aging cells before they become defective, enabling a healthy turn-over rate of new cells. When this is interrupted, non-functioning cells may abnormally divide, becoming cancerous.
The deadliest skin cancers are melanoma and Merkel cell carcinoma
Melanoma accounts for 75% of all deaths from skin cancer, even though it comprises only 5-10% of all cases diagnosed. What is lethal in these cases is that the skin cancer progresses rapidly and results in cancer traveling to other regions of the body; this is known as metastasis. One of the most difficult aspects of attempting to rid the body of skin cancer is that it is difficult to reliably detect where cancer has metastasized.
Scientists believe that a medicated ointment made from antisense oligonucleotides would provide a feasible topical treatment for skin cancer
As previously mentioned, the primary cause of cancers is the irregularity of cell apoptosis. There are several chemotherapy agents that cause cells to undergo apoptosis, however, interestingly, these chemotherapy agents don’t work for cancer that overexpresses a protein known as BCL-2 anti-apoptotic protein. As the name suggests, this protein resists cell death, meaning that melanoma patients experience drug resistance, with their cancer thriving despite chemotherapy.
A group of researchers have focused on the creation of a pharmaceutical agent that can overcome the drug resistance that affects melanoma patients. They were interested in antisense oligonucleotides (ASOs). ASOs are single-stranded molecules that have structures similar to DNA or RNA. Antisense pharmaceuticals are helpful because they can be used to prevent the creation of harmful proteins (such as anti-apoptotic proteins or proteins that cause drug resistance). Antisense pharmaceutical agents block ribosomes (the gene readers) from reading the gene that makes the harmful protein.
What does this mean for the future of skin cancer?
The researchers believe that ASOs in an ointment that allows them to be highly concentrated may be the most effective way to prevent secondary-tumor post-op. Now that gene mapping is far more developed, it is possible for more effective treatments like ASOs to be developed, which will allow the medical community to one day decrease the commonality or even completely eradicate skin cancer.
Written by Nikki Khoshnood, BHSc Candidate
Reference: Laikova, V, K. Et al. (April 17, 2019). Advances in the Understanding of Skin Cancer: Ultraviolet Radiation, Mutations, and Antisense Oligonucleotides as Anticancer Drugs. Molecules.