Researchers at Tel Aviv University found that immunotherapy with vaccines based on synthetic DNA may be an effective means of preventing brain metastases.

A new Tel Aviv University study has found that a known adjuvant – an ingredient used in vaccines that enhances the immune response – that contains synthetic DNA, may be an effective in preventing brain metastases in patients whose primary tumors have been excised.

The study was led jointly by Dr. Amit Benbenishty, Dr. Pablo Blinder, and Prof. Shmagar Ben-Eliyahu, in collaboration with Dr. Lior Mayo, Prof. Neta Erez, and Prof. Dritan Agalliu, and was published on March 28 in PLoS Biology.

According to Dr. Blinder, “Some 20-40% of lung, breast and melanoma cancer patients develop brain metastases, and current treatments for brain metastases are ineffective.” 

“Surgery for removing primary tumors is usually essential, but the period immediately before and after the surgery requires that all chemotherapy and radiotherapy be stopped,” he added.

“This,” he explained, “creates a high potential for the initiation and rapid progression of deadly brain metastases.”

According to Dr. Blinder, the study showed that CpG-C, an adjuvant of synthetic DNA material, reduces the development of brain metastases when injected intravenously during that time frame.

“When the drug is administered systemically, it crosses the blood-brain barrier and works by activating microglia, the brain’s primary immune cells, to kill invading tumor cells,” he said.

Currently, patients are given preventative whole-brain radiotherapy to reduce brain metastases – which has multiple negative side effects.

The new treatment, however, “gets the immune troops ‘ready for combat,’ in both the brain and the rest of the body,” he explained.

According to Dr. Blinder, CpG-C could be administered to cancer patients several days before a primary tumor removal, and continuing a few weeks after the surgery.

“We were able to verify that this treatment does not disrupt tissue healing, which is important in the post-operative period,” Prof. Ben-Eliyahu said, adding that “the treatment does not seem to increase the risk of other common surgery-related complications, such as an exaggerated post-operative inflammatory response.”

The group is currently conducting several studies to verify that the treatment does not risk patients’ health nor the surgery’s success.

“We are now testing the potential simultaneous use of anti-stress inflammatory drugs… [that] may mitigate the deleterious stress-inflammatory responses to surgery and potentially to CpG –C treatment.”

According to Prof. Ben-Eliyahu, “If these tests are successful we plan to conduct initial studies in cancer patients.”