Researchers in a multi-institutional study led by Cincinnati Children’s Hospital Medical Center slowed the growth of two particularly stubborn solid tumor cancers – neuroblastoma and peripheral nerve sheath tumors –without harming healthy tissues by inserting instructions to inhibit tissue growth into an engineered virus, according to study results published in the February 15 Cancer Research.
“Malignant solid tumors are still very difficult to treat effectively, especially without causing harm to normal tissues, so we need to find innovative therapeutic approaches,” said Timothy Cripe, M.D., Ph.D., a physician and researcher at Cincinnati Children’s. “In our study, this tumor-targeting viral therapy enhanced anti-tumor activity by stimulating multiple biological processes, including directly killing the cancer cells and reducing the formation of blood vessels that fed the tumors. These data support continuing development and study of our tumor-targeted viral therapy to fight cancer.”
Previous research has documented that oncolytic herpes simplex virus (oHSV) and similar viruses can infect and kill human cancer cells without harming normal, healthy cells or causing disease. In their study, Dr. Cripe and his colleagues genetically armed oHSV with a gene that carries instructions for a cancer-fighting protein, human tissue inhibitor of metalloproteinase 3 (TIMP3). TIMP3 blocks enzymes that aid the development and progression of cancer, called matrix of metalloproteinases (MMP). Specifically, MMPs help break down molecules that are important for the structural support and normal development of cells, organs and maintenance of tissues. When MMP activity becomes unbalanced, the enzyme plays a well-documented role in the formation of invasive and metastatic cancers, including pediatric neuroblastoma, the most common solid cancer tumor in childhood.
Researchers dubbed the tumor-targeted viral therapy created by combining of TIMP and oHSV as rQT3. In laboratory studies involving human cancer cells and mice designed to develop neuroblastoma or peripheral nerve sheath tumors, rQT3 reduced new blood vessel development and increased toxicity to both kinds of tumor cells. In addition, rQT3 treatment resulted in longer life spans in mice compared to mouse models receiving just saline or other treatments.
Dr. Cripe said the researchers also discovered that rQT3 reduced the number of circulating endothelial progenitors (CEP). CEPs are derived from blood marrow and circulate in the blood. They have the ability to become cells that line blood vessels to promote blood flow.
“Our findings suggest that therapeutic viruses can act systemically by limiting the mobilization and recruitment of bone-barrow derived progenitors, both CEPs and others, that contribute to the tumor microenvironment and growth, resulting in the restriction of new blood vessel growth that can feed tumors,” Dr. Cripe said.
Neuroblastoma is a solid tumor cancer that begins in the sympathetic nervous system and most often strikes children younger than 5 years old. For children younger than 2, or those with a single mass tumor, the combination of surgery and chemotherapy has led to cure rates of 90 to 95 percent. In older children or those with metastatic disease, neuroblastoma is a much harder to fight. Tumor cells are often able to survive ordinary doses of chemotherapy and radiation, leading to relapses that are difficult to cure. During the last three decades, Cincinnati Children’s has been a leader in developing high-dose chemotherapy used in combination with bone marrow transplants and other drug treatments to help improve outcomes for patients with high-risk neuroblastoma. Malignant peripheral nerve sheath tumors are cancers affecting the connective tissue surrounding nerves. The first-line treatment is surgical removal with chemotherapy or radiotherapy used as auxiliary therapies.
Nick Miller | EurekAlert!
New study from the University of Halle: How climate change alters plant growth
12.01.2018 | Martin-Luther-Universität Halle-Wittenberg
Disarray in the brain
18.12.2017 | Universität zu Lübeck
What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...
For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.
Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...
At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.
No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...
Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.
Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...
The oceans are the largest global heat reservoir. As a result of man-made global warming, the temperature in the global climate system increases; around 90% of...
08.01.2018 | Event News
11.12.2017 | Event News
08.12.2017 | Event News
17.01.2018 | Ecology, The Environment and Conservation
17.01.2018 | Physics and Astronomy
17.01.2018 | Awards Funding