An immunotherapy study on mice with cancer identified that Delta-24-ACT had a higher effectiveness rate than control treatments. Tumors developed more slowly and side effects were reduced.
Pediatric osteosarcoma is a rare, but aggressive form of cancer that mainly affects adolescents. Though it is rare to find in adults, this type of tumor is one of the most common among kids. The tumors more often show up in the wider ends of long bones, like the femur, tibia, and humerus.
Osteosarcoma is one of the silent-killer cancers because it’s aggressive and spreads quickly to other parts of the body. Like most cancers, osteosarcoma tends to be treated with both surgery and chemotherapy, which can remove around 70% (or less) of the tumor. For patients who have tumors that have metastasized or recurred, the survival rate drops to 20%.
The Immunotherapy Study
A recent study published in March showed that experimental immunotherapies using oncolytic viruses may have the potential to lengthen survival rates for high-risk patients.
Oncolytic viruses selectively replicate in cancer cells to achieve cancer cell death. There are 2 types: 1 genetically engineered virus and the other which occurs naturally. Both have the potential to destroy tumor-forming cells by releasing anti-cancer genes. These genes kill tumor cells while leaving healthy cells unaffected.
Researchers conducted this trial in Spain and it investigated the use of the oncolytic virus Delta-24-RGD, a virus that put 20% of patients in remission in a previous glioblastoma study.
Scientists introduced a new gene named Delta-24-ACT into this virus to make it more efficient at tumor killing. The modified virus produces 4-1BBL, which makes cytotoxic immune cells last longer. Researchers hypothesized that the immune response would lead these cells to kill cancer cells.
Immunotherapy Study Results
During the study, scientists tested the virus on osteosarcoma cells growing in tissue culture. They found that both Delta-24-RGD and Delta-24-ACT killed cancer cells in various osteosarcoma cell lines.
The scientists then tested the virus in mice with osteosarcoma cells in their bones. Results showed that the control group developed bone tumors faster than the treatment group.
They also determined that the treatment group had no severe side effects and that ultimately, treated mice lived longer on average than those in the control group.
Because osteosarcoma is an aggressive cancer with minimal successful outcomes, treatment options are few and far between. Scientists hope that these oncolytic viruses can shine a light on future treatments, especially for resistant cases, where quality of life is at stake. In these cases, it could help patients endure rigorous treatments better.
For more information on osteosarcoma, visit https://www.mayoclinic.org/diseases-conditions/osteosarcoma and to read more about the study, https://sciworthy.com/new-study-on-immunotherapy-for-bone-cancer/.
