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$1M grant funds research on quantitative imaging for tumors

“For children who are at risk of losing their vision, this project will bring a window of opportunity for physicians to start treatment earlier and save their vision,” says Marius George Linguraru, DPhil, MA, MSc.

A team from Children’s National Hospital is part of a project receiving a two-year grant of nearly $1,000,000 from the National Institutes of Health (NIH) for the first pediatric project in the Quantitative Imaging Network (QIN) of the National Cancer Institute (NCI). Marius George Linguraru, DPhil, MA, MSc, principal investigator from the Sheikh Zayed Institute for Pediatric Surgical Innovation at Children’s National Hospital in Washington, D.C., is one of two principal investigators on the project, which focuses on developing quantitative imaging (QI) tools to improve pediatric tumor measurement, risk predictions and treatment response. Roger Packer, M.D., Senior Vice President of the Center for Neuroscience & Behavioral Health, Director of the Gilbert Neurofibromatosis Institute and Director of the Brain Tumor Institute, is co-investigator.

The project, in collaboration with Children’s Hospital of Philadelphia and Children’s Hospital Colorado, centers on the most common type of brain tumor in children, called a low-grade glioma. This project focuses on a clinically challenging group of children with neurofibromatosis type 1 (NF1), the most common inherited tumor predisposition syndrome. Nearly 20% of children with NF1 will develop a low-grade glioma called optic pathway glioma (OPG). In children with this type of brain tumor, the growth occurs around the optic nerve, chiasm and tracts, also called the optic pathway, which connects the eye to the brain. OPGs can cause vision loss and even blindness. Permanent vision loss usually occurs between one and eight years of age with doctors closely monitoring the tumor with magnetic resonance imaging (MRI) to assess the disease progression.

“Our traditional two-dimensional measures of tumor size are not appropriate to assess the changes in these amorphous tumors over time or how the tumor responds to treatment,” says Linguraru. “This means physicians have difficulty determining the size of the tumor as well as when treatment is working. Research such as this can lead to innovative medical technologies that can improve and possibly change the fate of children’s lives.”

Dr. Linguraru is leading the technical trials on this project, which take place in the first two years, or phase one, starting in June 2020. Phase one focuses on improving the often inaccurate human measurements of tumor size by developing QI tools to make precise and automated measures of tumor volume and shape using machine learning. In this phase, the project will use and homogenize MRI data from multiple centers to develop predictive models of the treatment response based on the tumor volume that are agnostic to the differences in imaging protocols. By doing this, it will allow physicians to make more informed decisions about the treatment’s success and whether the child will recover their vision.

When phase one is complete, Linguraru and the project’s other principal investigator Robert A. Avery, DO, MSCE, neuro-ophthalmologist in the Division of Ophthalmology at Children’s Hospital of Philadelphia, will initiate the second phase, which includes validating the QI application on data from the first ever phase III clinical trial comparing two treatments for NF1-OPGs. Phase two is scheduled to start in the Summer 2022 and continue through Summer 2025.

“For children who are at risk of losing their vision, this project will bring a window of opportunity for physicians to start treatment earlier and save their vision,” says Linguraru. “For those children who won’t benefit from chemotherapy because the tumor poses no threat to their sight, this project will save them from having to go through that difficult treatment unnecessarily. It will be life-changing for the children and their families, which is what excites me about this QI application.”

This project is a collaboration between Children’s Hospital of Philadelphia and Children’s National Hospital in Washington, D.C., in partnership with Children’s Hospital of Colorado and University of Pennsylvania. Upon project completion, the QI application will provide a precision-medicine approach for NF1-OPGs and improve clinical outcomes for pediatric tumors.

Eugene Hwang in an exam room

Clinical Trial Spotlight: Creating a super army to target CNS tumors

Eugene Hwang in an exam room

Following the noted success of CAR-T cells in treating leukemia, Eugene Hwang, M.D., and a team of physicians at Children’s National are studying the efficacy of using these white blood cell “armies” to fight central nervous system (CNS) tumors.

Following the noted success of CAR-T cells in treating leukemia, physicians at Children’s National are studying the efficacy of using these white blood cell “armies” to fight central nervous system (CNS) tumors. Employing a strategy of “supertraining” the cells to target and attack three tumor targets as opposed to just one, Eugene Hwang, M.D., and the team at Children’s are optimistic about using this immunotherapy technique on a patient population that hasn’t previously seen much promise for treatment or cure. The therapy is built on the backbone of T cell technology championed by Catherine Bollard, M.B.Ch.B., M.D., director of the Center for Cancer and Immunology Research, which is only available at Children’s National. Hwang sees this trial as an exciting start to using T cells to recognize resistant brain cancer. “We have never before been able to pick out markers on brain cancer and use the immune system to help us attack the cancer cells. This strategy promises to help us find treatments that are better at killing cancer and lessening side effects,” he says.

This Phase 1 dose-escalation is designed to determine the safety and feasibility of rapidly generated tumor multiantigen associated specific cytotoxic T lymphocytes (TAA-T) in patients with newly diagnosed diffuse intrinsic pontine gliomas (DIPGs) or recurrent, progressive or refractory non-brainstem CNS malignancies. Pediatric and adult patients who have high-risk CNS tumors with known positivity for one or more Tumor Associated Antigens (TAA) (WT1, PRAME and/or surviving) will be enrolled in one of two groups: Group A includes patients with newly diagnosed DIPGs who will undergo irradiation as part of their upfront therapy and Group B includes patients with recurrent, progressive or refractory CNS tumors including medulloblastoma, non-brainstem high-grade glioma, and ependymoma, among others. TAA-T will be generated from a patient’s peripheral blood mononuclear cells (PBMCs) or by apheresis. This protocol is designed as a phase 1 dose-escalation study. Group A patients: TAA-T will be infused any time >2 weeks after completion of radiotherapy. Group B patients: TAA-T will be infused any time >2 after completing the most recent course of conventional (non-investigational) therapy for their disease AND after appropriate washout periods as detailed in eligibility criteria.

For more information about this trial, contact:

Eugene Hwang, M.D.
202-476-5046
ehwang@childrensnational.org

Click here to view Open Phase 1 and 2 Cancer Clinical Trials at Children’s National.

The Children’s National Center for Cancer and Blood Disorders is committed to providing the best care for pediatric patients. Our experts play an active role in innovative clinical trials to advance pediatric cancer care. We offer access to novel trials and therapies, some of which are only available here at Children’s National. With research interests covering nearly aspect of pediatric cancer care, our work is making great advancements in childhood cancer.

Roger Packer examines a patient

New guidelines advance treatment approach for children with low-grade gliomas

Roger Packer examines a patient

“We believe our understanding of LGGs combined with novel therapies will soon lead to a new standard of care for children,” says Roger J. Packer, M.D. “We are optimistic about the future for patients with this disease.”

Patients with low-grade gliomas (LGGs) will benefit from new recommendations from a group led by Roger J. Packer, M.D., senior vice president for the Center for Neuroscience and Behavioral Medicine, as well as clinicians, researchers and industry leaders from around the world, that were recently published in Neuro-Oncology. The new framework for LGGs will significantly advance the future of care for patients with these complex diseases and set a new path to expedite the translation of scientific advances into clinical care. The recommendations build on a treatment approach developed more than 25 years ago by Dr. Packer and his colleagues that revolutionized care for LGGs.

LGGs are both common and complicated, and one treatment approach does not work for all cases. Until now, there has not been a standardized way to categories the tumors to prescribe more effective and personalized treatment options. The new guidelines will provide clinicians with one mutually agreed upon set of recommendations to further advance the field and better diagnose and treat patients with LGGs.

Topics within the framework include:

  • Implications of the growing understanding of genomics underlying these tumors and how to apply to clinical practice
  • The need for more and better model systems to assess the likely benefits of new treatments for LGGs before exposing patients to new therapy
  • A review and assessment of what is needed for the design of future clinical trials
  • Evaluation of current therapies and the steps needed to expedite molecularly targeted therapy into late-stage clinical trials, including in those newly diagnosed with the disease so as to avoid less-personalized chemotherapy or radiotherapy

“We believe our understanding of LGGs combined with novel therapies will soon lead to a new standard of care for children,” says Dr. Packer.  “We are optimistic about the future for patients with this disease.”

The role of NG2 proteoglycan in glioma

A large number of staffers contribute to the Children's National team effort to unravel the mysteries of DIPG. We photograph a few essential players in Dr. Nazarian's lab.

What’s Known
Neuron glia antigen-2 (NG2) is a protein expressed by many central nervous system cells during development and differentiation. NG2-expressing oligodendrocyte progenitor cells have been identified as the cells of origin in gliomas, tumors that arise from the brain’s gluey supportive tissue. What’s more, NG2 expression also has been associated with childhood diffuse intrinsic pontine glioma (DIPG) an aggressive tumor that accounts for 10 percent to 20 percent of pediatric central nervous system (CNS) tumors. Radiation can prolong survival by a few months, but children diagnosed with DIPG typically survive less than one year.

What’s New
Researchers are searching for appropriate targets and effective drugs that offer some chance of benefit. A team of Children’s National Health System researchers investigated whether NG2 – which plays a critical role in proliferation and development of new blood vessels and promotes tumor infiltration – could be a potential target for cancer treatment. Of the various options, antibody-mediated mechanisms of targeting NG2 are feasible, but the size of antibodies limits their ability to cross the blood-brain barrier. “Due to its role in maintaining a pluripotent pool of tumor cells, and its role in tumor migration and infiltration, NG2 provides multiple avenues for developing therapeutics,” the research team concludes. “Moreover, the large extracellular domain of NG2 provides an excellent antigen repertoire for immunotherapeutic interventions. As such, further research is warranted to define the role and expression regulation of NG2 in CNS cancers.”

Questions for Future Research

Q: Because healthy oligodendrocyte progenitor cells are important for the child’s developing brain, how could further characterization of NG2 isoforms help prevent drugs from damaging those beneficial cells?

Q: Could NG2-binding peptides cross the blood-brain barrier to deliver anti-cancer therapies precisely to tumor sites?

Source: The Role of NG2 Proteoglycan in Glioma.” S. Yadavilli, E.I. Hwang, R. J. Packer, and J. Nazarian. Published by Translational Oncology on February 2016.