New brain tumor imaging technique uses protein found in scorpion venom

May 09, 2019

LOS ANGELES (May 9, 2019) - A novel imaging technique that uses a synthesized form of scorpion venom to light up brain tumors has shown promise in a clinical trial. The imaging system enables neurosurgeons to better see malignant growths that often are difficult to fully eliminate.

Results from the multi-institutional clinical trial, led by investigators from Cedars-Sinai and sponsored by Blaze Bioscience, Inc., appear in the journal Neurosurgery.

The new imaging technique that was studied uses a special high-sensitivity near-infrared camera developed at Cedars-Sinai, along with the imaging agent tozuleristide, or BLZ-100, developed by Blaze. The agent contains a synthetic version of an amino acid compound found in scorpion venom.

Like the natural form of the compound, the synthetic version is not toxic and binds to tumor cells. It is attached to a fluorescent dye that glows when stimulated by a near-infrared laser. Viewed through the camera, the imaging agent might allow neurosurgeons to detect the boundaries between tumors and healthy brain tissue during surgery, improving the opportunity for surgeons to remove tumor cells while sparing normal brain tissue.

"With this fluorescence, you see the tumor so much clearer because it lights up like a Christmas tree," said Adam Mamelak, MD, senior author and investigator in the trial.

That is important because of the sprawling nature of gliomas, the type of brain tumors imaged during the trial. Gliomas are highly lethal and comprise about 33% of all brain tumors. They can infiltrate brain tissue with tentacle-like structures, making them difficult to distinguish from normal brain tissue. They typically do not respond to traditional therapies such as chemotherapy and radiation. The key to extending patient survival depends on a surgeon's ability to detect and remove all parts of the tumor.

In the clinical trial, 17 adult patients with brain tumors were given varying doses of BLZ-100 before surgery. Despite the varying amounts of the drug given, the majority of tumors fluoresced, including both high- and low-grade gliomas. After surgery, patients were monitored for 30 days. Investigators found that none of the patients had any serious adverse responses to the drug, and that the imaging system was safe and could be useful for imaging the brain tumors during surgery.

More clinical trials are needed to further evaluate the safety of the imaging system and demonstrate the system's effectiveness before BLZ-100 can gain approval from the Food and Drug Administration, and the camera used in the trial must be refined before it can be used seamlessly in an operating room. But Mamelak said the clinical trial results were promising.

"For a surgeon, this seamless integration of fluorescence imaging into the surgical microscope is very appealing," Mamelak said.

Unlike other experimental systems that are bulkier or rely on multiple cameras, the new imaging system uses a single camera that takes both near-infrared and white-light images by alternating between a laser and normal white lights at very high speeds. This technology enables surgeons to easily switch back and forth between "normal" vision using a surgical microscope and fluorescent "super-vision" on a nearby monitor, in real time.

The next phase of this research, already underway, is a clinical trial involving pediatric brain tumors, taking place at up to 14 sites nationwide. This trial will serve as a data set for potential FDA approval. A similar adult clinical trial is also being planned. Although Mamelak is not directly involved in performing research during this phase, he and others are eager to see if the imaging approach has applications beyond neurosurgery.

"The technique in this study holds great promise not only for brain tumors but for many other cancer types in which we need to identify the margins of cancers," said Keith L. Black, MD, chair of the Department of Neurosurgery at Cedars-Sinai. "The ultimate goal is to bring greater precision to the surgical care we provide to our patients."
-end-
Discolsure: Pramod Butte, MBBS, PhD and Adam Mamelak, MD are consultants for Blaze Bioscience, Inc. Pramod Butte, MBBS, PhD; Keith Black, MD and Adam Mamelak, MD are shareholders of Blaze Bioscience, Inc.

Read more on the Cedars-Sinai Blog: This Gene May Explain Why Some Brain Tumors Grow so Fast

Cedars-Sinai Medical Center

Related Tumor Cells Articles from Brightsurf:

A more sensitive way to detect circulating tumor cells
Breast cancer is the most frequently diagnosed cancer in women, and metastasis from the breast to other areas of the body is the leading cause of death in these patients.

Cancer researchers train white blood cells to attacks tumor cells
Scientists at the National Center for Tumor Diseases Dresden (NCT/UCC) and Dresden University Medicine, together with an international team of researchers, were able to demonstrate that certain white blood cells, so-called neutrophil granulocytes, can potentially - after completing a special training program -- be utilized for the treatment of tumors.

How to prevent the spread of tumor cells via the lymph vessels
Scientists from the German Cancer Research Center and the Mannheim Medical Faculty of the University of Heidelberg identified a new way to block the dangerous spread of tumor cells via lymphatic vessels.

The CNIO reprograms CRISPR system in mice to eliminate tumor cells without affecting healthy cells
CNIO researchers destroyed Ewing's sarcoma and chronic myeloid leukaemia tumor cells by using CRISPR to cut out the fusion genes that cause them.

Feeding off fusion or the immortalization of tumor cells
Despite all recent progress, cancer remains one of the deadliest human diseases.

How do tumor cells divide in the crowd?
Scientists led by Dr. Elisabeth Fischer-Friedrich, group leader at the Excellence Cluster Physics of Life (PoL) and the Biotechnology Center TU Dresden (BIOTEC) studied how cancer cells are able to divide in a crowded tumor tissue and connected it to the hallmark of cancer progression and metastasis, the epithelial-mesenchymal transition (EMT).

How tumor cells evade the immune defense
Scientists are increasingly trying to use the body's own immune system to fight cancer.

Engineered immune cells recognize, attack human and mouse solid-tumor cancer cells
CAR-T therapy has been used successfully in patients with blood cancers such as lymphoma and leukemia.

New pathway to attack tumor cells identified
A study led by the Institut de Neurociències (INc-UAB) describes a new strategy to tackle cancer, based on inducing a potent stress in tumor causing cell destruction by autophagy.

Nutrient deficiency in tumor cells attracts cells that suppress the immune system
A study led by IDIBELL researchers and published this week in the American journal PNAS shows that, by depriving tumor cells of glucose, they release a large number of signaling molecules.

Read More: Tumor Cells News and Tumor Cells Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.