Brain tumors especially Glioblastomas are difficult to treat due to their ability to spread roots and tendrils throughout the brain tissue making surgical removal impossible, other treatment options such as chemotherapy and radiation therapy are also ineffective ultimately resulting in low survival rates. The aggressive nature of these tumors unfortunately kills patients within two years of diagnosis.
Tests on mice by a research team at the University of Carolina showed the ability of adult skin cells to transform into stem cells that can be used to track down tumors and kill it as cancerous cells emit chemical signals that attract stem cells which consider tumors as wounds that need healing. The researchers used this phenomenon to shrink brain tumors in mice to about 2-5% of the original size.
The research team took skin cells specifically fibroblasts that have the ability to generate collagen and connective tissue and reprogrammed them into neural stem cells. These neural stem cells hunt for cancer cells in the brain and fasten themselves onto them, but don’t have the ability to fight against the tumor. Therefore scientists had to genetically engineer the stem cells to help them express a cancer-killing protein. This resulted in an increase in the life span of the effected mice by about 160-220%.
The difficulty was in acquiring neural stem cells from humans as it’s a tricky process, the safest technique being a two-step process that involved induction of adult skin cells to form neural stem cells. The drawback here was the time taken for this technique, speed is crucial as the patients don’t have much time to wait for the establishment of therapies. The research team keeping this in mind developed a process that could produce the required neural stem cells in a span of just 4days by skipping one step (conversion of skin cell to a generic stem cell) completely by treating the adult skin cells with a mixture of chemicals. Tests on tumors in petri dishes as well as animal models showed that these cells retained the same properties and behaved exactly the same.
The last step involved the engineering of these neural stem cells to carry a protein functioning as a trigger that activates a pro-drug in a limited circumference encircling the stem cell instead of affecting the entire body; this allowed the drug to target only the desired area and reduce the side effects of chemotherapy and radiation therapy. The lead scientist of this research Shawn Hingtgen has told that they are just 1-2 years away from clinical trials and believes it to be a big step toward the treatment of Glioblastomas.
Artile by Srividya