Neurology and Neurosurgery

Every day fetuses remain in utero critical to preserving normal brain development

preemieimage

If it does not jeopardize the health of the pregnant mother or her fetus, pregnancies should be carried as close to full term as possible to avoid vulnerable preemies experiencing a delay in brain development, study results published October 28 in Pediatrics indicate.

Some 15 million infants around the world – and 1 in 10 American babies – are born prematurely. While researchers have known that preemies’ brain growth is disturbed when compared with infants born at full term, it remained unclear when preemies’ brain development begins to veer off course and how that impairment evolves over time, says Catherine Limperopoulos, Ph.D., Director of the Developing Brain Research Laboratory at Children’s National Health System and senior study author.

A look at the research

In order to shine a spotlight on this critical phase of fetal brain development, Limperopoulos and colleagues studied 75 preterm infants born prior to the 32th gestational week who weighed less than 1,500 grams who had no evidence of structural brain injury. These preemies were matched with 130 fetuses between 27 to 39 weeks gestational age.

The healthy fetal counterparts are part of a growing database that the Children’s National Developing Brain Research Laboratory has assembled. The research lab uses three-dimensional magnetic resonance imaging to carefully record week-by-week development of the normal in utero fetal brains as well as week-by-week characterizations of specific regions of the fetal brain.

The availability of time-lapsed images of normally developing brains offers a chance to reframe research questions in order to identify approaches to prevent injuries to the fetal brain, Limperopoulos says.

“Up until now, we have been focused on examining what is it about being born too early? What is it about those first few hours of life that leaves preemies more vulnerable to brain injury?” she says. “What is really unique about these study results is for the very first time we have an opportunity to better understand the ways in which we care for preemies throughout their hospitalization that optimize brain development and place more emphasis those activities.”

When the research team compared third-trimester brain volumes, preemies showed lower volumes in the cerebrum, cerebellum, brainstem, and intracranial cavity. The cerebrum is the largest part of the brain and controls speech, thoughts, emotions, learning, as well as muscle function. The cerebellum plays a role in learning and social-behavioral functions as well as complex motor functions; it also controls the balance needed to stand up and to walk. The brainstem is like a router, ferrying information between the brain, the cerebellum, and the spinal cord.

“What this study shows us is that every day and every week of in utero development is critical. If at all possible, we need to keep fetuses in utero to protect them from the hazards that can occur in the extra uterine environment,” she says.

Transgender adolescents on the autism spectrum, and the first clinical guidelines for care

Evidence indicates a link between transgenderism and autism spectrum disorders (ASD). John Strang, Psy.D., a neuropsychologist in the Center for Autism Spectrum Disorders at Children’s National Health System, has dedicated his career to learning more about this co-occurrence and led a group of experts who recently released the first clinical guidelines for the care of transgender adolescents with ASD.

Through a comprehensive international search procedure, the research team, led by Dr. Strang, identified 22 experts in the care of transgender youth with autism. The expert group from around the world worked together for one year to create guidelines, putting processes in place to avoid interpersonal influence or bias.

The findings, published in the Journal of Clinical Child and Adolescent Psychology, outline the first initial clinical guidelines for treating transgender adolescents with ASD.

With overall 89.6 percent consensus achieved among the identified experts, key recommendations include the importance of assessing for ASD among transgender youth, and assessing for gender concerns among youth on the autism spectrum.

More study findings and recommendations

The study also indicates that gender-related medical treatments, including cross-sex hormone therapy, are appropriate for some youth with ASD, but emphasizes the importance of providing more extended time and supports in many cases to allow an adolescent with autism to explore a range of options regarding gender.

The guidelines emphasize that for many transgender youth with autism, parents must play a more active role. “Teens on the autism spectrum often struggle understanding how others perceive them,” Dr. Strang said. “Our study found that many transgender youth on the autism spectrum require specific coaching and supports in how to achieve their gender-related needs regarding gender presentation.”

Several risks for transgender adolescents with autism were emphasized in the study, including around physical safety and obtaining employment. “Trans youth are at increased risk for bullying, persecution, and violence in the community, and those on the autism spectrum are at even higher risk, as they often struggle to read social cues and recognize potentially dangerous social situations,” Dr. Strang said.

The importance of this study

The study group did not achieve consensus around specific guidelines for when an adolescent is appropriate for commencing medical gender treatments (e.g., cross-sex hormones). A majority (about 90 percent) of the expert participants elected to identify themselves as co-authors of the study, including many well-known clinicians across the United States as well as clinicians from The Netherlands.

“Until now, care for individuals with autism and gender concerns has been a matter of individual clinician judgment. This study has allowed for dialogue and discernment between the world’s experts in this field to establish the first recommendations for care,” Dr. Strang said.

Dr. Strang is currently working on a follow-up study to more directly capture the voices and experiences of youth with this co-occurrence, as key stakeholders and collaborators in the research.

hands on simulation training at AAP

At AAP: hands-on simulation training with life-saving technology

aap_nshah_techdependentinfants_atmospheric

Recent medical breakthroughs have enabled very premature infants and children with rare genetic and neurological diseases to survive what had once been considered to be fatal conditions. This has resulted in a growing number of children with medically complex conditions whose very survival depends on ongoing use of technology to help their brains function, their lungs take in oxygen, and their bodies remain nourished.

“Many pediatricians care for technology-dependent children with special health needs,” says Neha Shah, M.D., M.P.H., an associate professor of pediatrics in the Division of Hospitalist Medicine at Children’s National Health System. “These kids have unique risks – some of which may be associated with that life-saving device malfunctioning.” Because there is no standard residency training for these devices, many clinicians may feel ill-equipped to address their patients’ device-related issues. To bridge that training gap, Dr. Shah and co-presenters, Priti Bhansali, M.D., M.Ed., and Anjna Melwani, M.D., will lead hands-on simulation training during the American Academy of Pediatrics 2016 National Conference.

“Inevitably, these things happen at 3 in the morning,” Dr. Shah adds. “Individual clinicians’ skill level and comfort with the devices varies. We should all have the same core competency.”

How the training works

During the simulation, the audience is given a specific case. They have eight minutes to troubleshoot and resolve the issue, using mannequins specially fitted with devices, such as trach tubes and feeding tubes, in need of urgent attention. Depending on their actions, the mannequin may decompensate with worsened breathing and racing heartbeats. The high-stakes, hands-on demo is followed by a 12-minute debrief, a safe environment to review lessons learned. Once they complete one simulation, attendees move to the next in the series of four real-life scenarios.

“We’ve done this a few times and my heart rate still goes up,” Dr. Shah admits. After giving similar training sessions at other academic meetings, participants said that having a chance to touch and feel the devices and become familiar with them in a calm environment is a benefit.

Dr. Shah came up with the concept for the hands-on training by speaking with a small group of peers, asking about how comfortable they felt managing kids with medical complex cases. The vast majority favored additional education about common devices, such as gastronomy tubes, tracheostomy tubes, and ventriculoperitoneal shunts.  In addition to the in-person training, the team has created a web-based curriculum discussing dysautonomia, spasticity, gastroesophageal reflux disease, enteric feeding tubes, venous thromboembolism, and palliative care, which they described in an article published in the Fall 2015 edition of the Journal of Continuing Education in the Health Professions.

“Most times, clinicians know what they need to do and the steps they need to follow. They just haven’t done it themselves,” Dr. Bhansali adds. “The simulation forces people to put their hands on these devices and use them.”

AAP 2016 presentations:
Saturday, October 22, 2016

  • W1059- “Emergencies in the Technology-Dependent Child: What Every Pediatrician Should Know” 8:30 a.m. to 10 a.m. (SOLD OUT)
  • W1131-  “Emergencies in the Technology-Dependent Child: What Every Pediatrician Should Know” (Encore) 2 p.m. to 3:30PM
Chima Oluigbo

The benefits of deep brain stimulation for pediatric patients

Chima Oluigbo

There was no effective treatment for uncontrolled, difficult, and sometime painful movements associated with movement disorders. That is, before the development of deep brain stimulation (DBS) techniques.

Children’s National Health System is one of only two children’s hospitals with fully integrated DBS programs. Chima Oluigbo, M.D., who leads the pioneering Deep Brain Stimulation Program within Children’s Division of Neurosurgery, is one of few pediatric deep brain stimulation experts in North America and cross-trained in pediatric and functional neurosurgery.

Dr. Oluigbo says the effects of DBS are often dramatic: 90 percent of children with primary dystonia show up to 90 percent symptom improvement.

A 6-year-old boy with dystonia so severe that his body curved like a “C” was one of the first patients to undergo the procedure at Children’s National. Six weeks later, he gained the ability to sit straight and to control his hands and legs. He also was able to smile, an improvement that brought particular joy to his parents.

Inside the brain with movement disorders

Patients with movement disorders experience difficulties due to neurological dysfunction that impact the speed, fluency, quality, and ease in which they move. In these cases, neurons in the brain’s motor circuits misfire. Through the use of DBS, neurosurgeons can synchronize neuronal firing and accomplish the previously impossible: restoring muscle control to patients with these disorders.

Movement disorders are common in children. “It’s not just numbers, it’s also about impact. Think about the potential of a child who is very intelligent and can contribute to society. When that child is not able to contribute because he or she is disabled by a movement disorder, the lost potential is very significant. It has an impact,” Dr. Oluigbo says.

What is deep brain stimulation?

DBS uses an implantable device to send continuous, low-level electrical impulses to areas deep within the brain. The impulses prevent the brain from firing abnormal signals that are linked to movement disorders and seizures. When a child is considered to be a candidate for the technique, here’s what happens next:

  1. Imaging: Magnetic resonance imaging (MRI) helps pinpoint the area of brain tissue responsible for movement disorders and informs the treatment plans.
  2. Neurotransmitter implant procedure: Using minimally invasive neurosurgery techniques, doctors access the brain through a tiny incision in the child’s skull and place thin, insulated wires (leads) in the area of brain tissue responsible for the condition.
  3. Pulse generator implant procedure: The pulse generator (neurostimulator) is a battery-operated device that sends low-level electrical impulses to the leads. During a separate procedure, the pulse generator is implanted near the child’s collarbone. Leads are threaded under the child’s skin to connect with the pulse generator.
  4. Stimulation treatments: Once the leads and pulse generator are connected, the child receives a continuous stream of electrical impulses. Impulses are generated by the neurostimulator, travel through the leads, and end up in the deep tissue of the brain. Here, they block abnormal signals that are linked to the child’s movement disorder.
  5. Follow-up care: The child will likely need deep brain stimulation throughout his or her lifetime to make sure the device is working correctly and to adjust the neurotransmitter settings to meet his or her changing needs.

Deep brain stimulation at Children’s National

Children’s National is currently conducting clinical trials seeking to expand the use of this procedure to patients with cerebral palsy, one of the most common dystonias. The effective use of deep brain stimulation requires ongoing attention from a multidisciplinary team (from neuropsychology to rehabilitation medicine), giving seamless care under one roof.

There is evidence to suggest that this technique could be used to aid people with memory disorders, patients in minimally conscious states, and patients with incurable epilepsies.

Dr. Roger Packer

New brain tumor research collaborative taps Children’s for scientific director

Dr. Roger Packer

This year, more than 4,600 children and adolescents (0-19 years) will be diagnosed with a pediatric brain tumor. Brain tumors have now passed leukemia as the leading cause of pediatric cancer-related deaths. Despite this, there has never been a drug developed specifically to treat pediatric brain tumors and for many pediatric brain tumor-types, no standards of care or effective treatment options exist. In particular, pediatric high-grade gliomas have no standard of care and a very low survival rate.

To combat this, the National Brain Tumor Society (NBTS), the largest nonprofit dedicated to the brain tumor community in the United States, with its partner, the St. Baldrick’s Foundation, the largest private funder of childhood cancer research grants, as well as several world-renowned experts in the field of pediatric neuro-oncology, announced a new awareness and fundraising campaign to support a major translational research and drug discovery program. The campaign, called “Project Impact: A Campaign to Defeat Pediatric Brain Tumors,” was unveiled at the National Press Club in Washington, DC, on Sept. 12. Watch the live streaming replay.

Children’s National brain tumor expert leads the way
The collaborative hopes to improve clinical outcomes for pediatric brain tumor patients and inform the development of the first standard of care for treating pediatric high-grade gliomas, including DIPG – the deadliest of pediatric cancers.

Roger J. Packer, M.D., Senior Vice President of the Center for Neuroscience and Behavioral Medicine and Director of Brain Tumor Institute at Children’s National Health System, serves as the Scientific Director of the Defeat Pediatric Brain Tumors Research Collaborative.

“Treatment of pediatric high-grade gliomas has been extremely frustrating with little progress made over the past quarter century,” said Dr. Packer. “New molecular insights provide hope that therapies will be dramatically more effective in the very near future. In the last two years alone we have had great breakthroughs, primarily identifying genes which are critical in development of new pediatric treatments. But we need to maintain forward momentum from discovering the molecular and genetic underpinnings of these tumors, to understanding how these changes drive these tumors, and to ultimately developing effective, biologically precise therapies. This is a major opportunity for the field, patients, and their families.”

Pediatric high-grade gliomas make up to 20 percent of all pediatric brain tumors with roughly 500-1,000 new diagnoses every year. These tumors are WHO Grade III and Grade IV gliomas, including: pediatric glioblastoma (GMB); glioma malignant, NOS; pediatric anaplastic astrocytoma; anaplastic oilgodendroglioma; giant cell glioblastoma; gliosarcoma; and diffuse intrinsic pontine gliomas (DIPG).

David Arons, CEO of the National Brain Tumor Society said, “Researching and developing new treatments for pediatric brain tumors is a particularly challenging task, which faces multiple – but interrelated – barriers that span the research and development spectrum from small patient populations, lack of effective preclinical models, to complex basic biology, regulatory hurdles and economic disincentives. To overcome these complex challenges, and get better treatments to patients, we needed to create an equally sophisticated intervention. We believe that having groups with complementary skills work together in a coordinated effort, sharing data and expertise, and tackling the problem from multiple angles as one team is the starting point for greater and faster progress.”

How the collaborative is set up
The model for the collaborative consists of scientists and researchers who will each lead interrelated “Cores” to work on critical areas of research simultaneously and in concert with one another, encouraging sharing of findings real time. This design allows new findings to quickly move onto the next stage of research without barriers or other typical delays, significantly speeding up the research process.

Dr. Packer said the goal of this research collaboration is to work with pediatric brain tumor researchers from around the world to discover new treatments for children in the next two to three years, instead of the next decade.

Javad Nazarian

Surviving pediatric diffuse intrinsic pontine glioma

Mutations in histone-encoding genes are associated with the vast majority of pediatric DIPG cases.

For more than four decades, clinicians around the nation have been giving the parents of pediatric patients diagnosed with diffuse intrinsic pontine glioma (DIPG) the same grim prognosis. In the past five years, there has been an explosion of innovative research at Children’s National Health System and elsewhere that promises to change that narrative. That’s because the black box that is DIPG is beginning to divulge its genetic secrets. The new-found research knowledge comes as a direct result of parents donating specimens, judicious shepherding of these scarce resources by researchers, development of pre-clinical models, and financing from small foundations.

From just 12 samples six years ago, Children’s National has amassed one of the nation’s largest tumor bio banks – 3,000 specimens donated by more than 900 patients with all types of pediatric brain tumors, including DIPG.

Such donated specimens have led to the identification of H3K27M mutations, a groundbreaking finding that has been described as the single-most important discovery in DIPG. Mutations in histone-encoding genes are associated with the vast majority of pediatric DIPG cases.

Histone mutations (also referred to as oncohistones) are sustained in the tumor throughout its molecular evolution, found a research team led by Javad Nazarian, Ph.D. Not only were H3K27M mutations nearly ubiquitous in all samples studied, the driver mutation maintained partnerships with other secondary mutations as DIPG tumor cells spread throughout the developing brain. Children’s National researchers have identified tumor driver mutations and obligate partner mutations in DIPG. They are examining what happens downstream from the histone mutation – changes in the genome that indicate locations they can target in their path toward personalized medicine. The value of that genomic knowledge is akin to emergency responders being told the specific house where their help is needed, rather than a ZIP code or city name, Dr. Nazarian says. While there is currently no effective treatment for DIPG, new research has identified a growing number of genomic targets for future therapeutics.“That changed the dynamic,” says Dr. Nazarian. “In DIPG clinical research, nothing had changed for 45 years. Now we know some of the genomic mutations, how the tumor was evolving – gaining new mutations, losing mutations. With precision medicine, we can target those mutations.”

Another study led by neuro-oncologist Eugene Hwang, M.D., reported the most comprehensive phenotypic analyses comparing multiple sites in a young girl’s primary and metastatic tumors. This study showed that despite being uniform, small molecules (mRNA) could be used to distinguish an evolved tumor from its primary original tumor mass.Key to this multidisciplinary work is collaboration across divisions and departments. Within the research lab, knowledge about DIPG is expanding.

Each member of the DIPG team – neurosurgery, neuro-oncology, immunology, genomics, proteomics – feeds insight back to the rest of the team, accelerating the pace of research discoveries being translated into clinical care. Among the challenges that the team will address in the coming months is outmaneuvering tumors that outsmart T-cells (immune cells).

“What is happening in the checkpoint inhibitor field is exciting,” says Catherine M. Bollard, MBChB, MD, Chief of Allergy and Immunology and Director of the Program for Cell Enhancement of Technologies for Immunotherapy. “The inhibitors work by reversing the ‘off’ switch – releasing the brake that has been placed on the T-cells so they can again attack multiple tumor proteins. The next exciting step, and novel to Children’s National, will be to combine this approach with T-cell therapies specifically designed to attack the DIPG tumors. Unlike the use of combination chemotherapy, which has had a limited impact, we hope that the novel combination of immunotherapeutic approaches will offer the hope of a potential cure.”

Dr. Hwang, another member of the multidisciplinary team, adds: “When you’re looking at the landscape – for me, at least – it starts and ends with how my patients are doing. There are kids for whom we have had great successes in improving survival rates in some cancers, like leukemia, and some where the needle has moved nowhere, like DIPG. We’re still trying to figure out the whole picture of who responds. The immune system is present in all kids. Its ability to attack is present in all kids.”

Children’s National is one of the few hospitals in the nation that conducts brainstem biopsies for DIPG and does so with very little chance of complications. The pons is like a superhighway through which nerves pass, making it instrumental in smooth operation of such vital functions as breathing, heart rate, sleeping, and consciousness. The ability of neurosurgeon Suresh Magge, MD, to perform such sensitive biopsies upends conventional wisdom that these procedures were inherently too dangerous. Within two weeks of diagnosis, genomics analyses are run to better understand the biology of that specific tumor. Within the following weeks, the tumor board occurs, and patients with DIPG are placed on therapy that best targets their tumor’s mutations.

The black box that is diffuse intrinsic pontine glioma is beginning to divulge its genetic secrets.

Despite an increasing number of experimental therapies tested via clinical trials, more than 95 percent of children with DIPG die within two years of diagnoses. Biomarkers that point to DIPG – like the copies of DNA that tumors shed and leave behind in the bloodstream – could enable creation of liquid biopsies, compared with today’s surgical approach.

Children’s also is making a concerted effort to create preclinical models of DIPG. Preclinical models will be used to winnow the field of potential therapeutics to the candidates most likely to help children survive DIPG. The preclinical tumor cells will be labeled with luciferase – enzymes that, like photoproteins, produce bioluminescence – permitting the researcher to visually see the formation, progression, and response of DIPG tumors to treatment in preclinical settings.

These preclinical models could be used to test multiple drug combinations in conjunction with radiation therapy. Molecular signatures and response to treatment could then be assessed to learn how the tumor resists therapy. Due to the obligate partnerships between driver mutations and secondary mutations, the research team already knows that effective DIPG medicines will need more than one target. If there were a single mutation, that would be like having a single master key to open many locks. Multiple mutations imply that more than one key will be needed. Thus, the search for cures for DIPG will necessitate taking a multi-pronged approach.

Combined drug regimens, including those created with proprietary technology, with or without radiation, will be keys to targeting myriad mutations in order to kill tumors where they are. Those drug combinations that demonstrate they can do their jobs – slowing tumor growth, increasing chances of survival, taming toxicity – will be selected for clinical application.

Immunotherapy leverages T-cells, the immune system’s most able fighters, to help in the overall goal of extending patients’ survival. One of the most challenging aspects of pediatric brain tumors is the body does a very good job of shielding the brain from potential pathogens. Precise drug delivery means finding innovative ways for therapeutics to cross the blood-brain barrier in order to reach the tumor. The team has identified one such potential target, the protein NG2, which may represent a good target for immune therapy. The protein is expressed in primitive cells that have not become specialized – meaning there may be an opportunity to intervene before it is driven to become a tumor cell.

Related resources
Research at a Glance: Clinicopathology of diffuse intrinsic pontine glioma and its redefined genomic and epigenomic landscape
Research at a Glance: The role of NG2 proteoglycan in glioma
Research at a Glance: Spatial and temporal homogeneity of driver mutations in diffuse intrinsic pontine glioma
Research at a Glance: Histological and molecular analysis of a progressive diffuse intrinsic pontine glioma: a case report

Neurology and neurosurgery update: whole exome sequencing, Sesame Workshop

May 9, 2016 WES yields clinical diagnoses for 42 percent, ending ‘diagnostic odyssey’.
Whole exome sequencing (WES), a method to look at all the genes in the genome at once, yielded clinical diagnoses for 42 percent of patients whose white matter abnormalities had been unresolved an average of eight years, ending families’ “prolonged diagnostic odyssey.”  White matter disorders, which affect 1 in 7,000 children born each year, are progressive and involve age-related weakness in the region of the nerves that connect various parts of the brain to each other and to the spinal cord. Nine of 28 named authors of the study, published online May 9, 2016 in Annals of Neurology, are affiliated with Children’s National Health System.

April 6, 2016 Georgetown, Children’s National researchers to evaluate Sesame Workshop’s Autism Initiative.
Sesame Workshop, the nonprofit educational organization behind Sesame Street, has selected Georgetown University Medical Center and Children’s National Health System researchers to lead an evaluation of  “Sesame Street and Autism: See Amazing in All Children,” an initiative developed to reduce stigma and build understanding about autism spectrum disorder. Sesame Workshop launched a new phase of its autism initiative in early April. Last year, Sesame Street introduced Julia, an autistic preschool digital Muppet, and accompanying resources, such as an app, videos, storybooks, and daily routine cards as part of the Sesame Street and Autism: See Amazing in All Children initiative. Now ready for evaluation, Sesame Workshop awarded a grant for real-world testing of the materials to Bruno Anthony, PhD, deputy director of the Georgetown Center for Child and Human Development in collaboration with his wife and research collaborator Laura Anthony, PhD, at the Center for Autism Spectrum Disorder at Children’s National.

In Brief- Fetal Medicine

Cognitive training exercises at home help kids with sickle cell boost visuospatial working memory

A team led by Children’s National Health System clinicians and research scientists attempted to identify novel approaches to boost working memory in children who suffer from sickle cell disease.

A team led by Children’s National Health System clinicians and research scientists attempted to identify novel approaches to boost working memory in children who suffer from sickle cell disease.

Youths with sickle cell disease who used hand-held computers to play game-like exercises that get harder as a user’s skill level rises improved their visuospatial working memory (WM). Children with sickle cell disease, however, completed fewer training sessions during an initial study compared with children with other disease-related WM deficits.

A team led by Children’s National Health System clinicians and research scientists attempted to identify novel approaches to boost WM in children who suffer from sickle cell disease. Kids who have this red blood cell disorder inherit abnormal hemoglobin genes from each parent. Rather than slipping through large and small vessels to ferry oxygen throughout the body, their stiff, sickle-shaped red blood cells stick to vessel walls, impeding blood supply and triggering sudden pain. Children with sickle cell disease have more difficulty completing tasks that place demands on one’s WM, the brain function responsible for temporarily remembering information and manipulating that information to facilitate learning and reasoning. As a result, they’re more likely to repeat a grade, require special academic services, and to have difficulty maintaining employment as adults.

Because computerized cognitive training programs have been used with success to boost WM for children with other health conditions, such as childhood cancer, the research team sought to examine the feasibility of using the technique for kids with sickle cell disease. “This small study highlights the challenges and opportunities of implementing a home-based cognitive training intervention with youths who have sickle cell disease,” says Steven J. Hardy, PhD, a pediatric psychologist in the Divisions of Hematology, Oncology, and Blood and Marrow Transplantation at Children’s National. “While a larger, randomized controlled clinical trial is needed to better characterize efficacy, our initial work indicates that Cogmed is acceptable and moderately feasible in this population.”

Children’s National is home to the Sickle Cell Disease (SCD) Program, one of the nation’s largest, most comprehensive pediatric programs that cares for 1,350 patients younger than 21 annually. Over 15 months, the team recruited youths aged 7 to 16 participating in the program who had an intelligence quotient of at least 70 and an absolute or relative memory deficit. Those who lacked access to a tablet computer were loaned an iPad Mini 2 loaded with Cogmed RM, an interactive audiovisual cognitive training program that consists of exercises that get progressively more challenging. A clinical psychologist provided coaching and moral support through weekly telephone calls to review progress and challenges, and to offer tips on how to optimize the youths’ progress.

Six of 12 eligible participants – all girls – completed by finishing at least 20 sessions of the program. The mean number of sessions completed was 15.83, and the kids spent a median of 725 minutes working actively on Cogmed exercises. “Participants who completed Cogmed indicated that they perceived greater levels of social support from teachers,” Hardy and colleagues write in the study, published by Pediatric Blood & Cancer. “[T]here was not a statistical difference in perceived parent support.”

Among those children who completed Cogmed, standard scores increased an average of 5.05 on a measure of visuospatial short-term memory, 19.72 on a measure of verbal WM, 27.53 on a measure of visuospatial short-term memory, and 23.82 on a measure of visuospatial WM. The researchers also observed a normalizing of memory functioning for those who finished Cogmed, as a significant portion of participants scored below the average range before using Cogmed and most scored in the average range or higher on memory tests after finishing the program.

“In this initial feasibility trial, adherence to Cogmed was lower than expected (50 percent completion) compared to adherence rates of other samples of children with medical histories, including patients with symptomatic epilepsy and youth treated for cancer,” Hardy and co-authors write. “Thus, additional modifications may be needed to achieve consistent delivery of the intervention to youth with SCD.”

Related Resources: Research at a Glance

Analysis of a progressive diffuse intrinsic pontine glioma: a case report

rg_histological-dipg-image

What’s Known
Despite multiple clinical trials testing an assortment of new treatments, the survival rate for diffuse intrinsic pontine glioma (DIPG) remains abysmal, with most children succumbing to the pediatric brainstem tumor within 12 months of diagnosis. Focal radiation therapy, the primary treatment approach, has not improved overall survival. While the majority of DIPG tumors grow within the brainstem, metastases can occur elsewhere in the brain. Due to recent availability of tissue, new data are emerging about the biologic behavior of tumors, details that could be instrumental in constructing optimal treatment strategies.

What’s New
An otherwise healthy 9-year-old girl developed weakness in the left side of her face; magnetic resonance imagining revealed T2/FLAIR hyperintensity centered within and expanding the pons. Despite various treatments, her pontine lesion increased in size and new metastases were noted. The team led by Children’s National Health System researchers is the first to report comprehensive phenotypic analyses comparing multiple sites in primary and distant tumors. All tumor sites displayed positive staining for the H3K27M mutation, a mutation described in more than two-thirds of DIPGs that may portend a worse overall survival. Persistence of mutational status across multiple metastatic sites is particularly important since the effectiveness of some therapeutic approaches relies on this occurring. mRNA analyses, by contrast, identified a small number of genes in the primary tumor that differed from one metastatic tumor. This divergence implies that a single biopsy analysis for mRNA expression has the potential to be misleading.

Questions for Future Research
Q: Because a small cohort of genes in the girl’s primary tumor were different from genes in portions of the metastatic tumor, would genomic and proteomic analyses provide additional details about this genetic evolution?
Q: How do site-specific differences in mRNA expression affect decisions about which therapies to provide and in which order?

Source: Histological and Molecular Analysis of a Progressive Diffuse Intrinsic Pontine Glioma and Synchronous Metastatic Lesions: A Case Report.” J. Nazarian, G.E. Mason, C.Y. Ho, E. Panditharatna, M. Kambhampati, L.G. Vezina, R.J. Packer, and E.I. Hwang. Published by Oncotarget on June 14, 2016.

researcher using ice bucket in lab

Spatial and temporal homogeneity of driver mutations in diffuse intrinsic pontine glioma

What’s Known
Needle biopsies help to guide diagnosis and targeted therapies for diffuse intrinsic pontine gliomas (DIPGs), which make up 10 percent to 15 percent of all pediatric brain tumors but carry a median survival of 9 to 12 months. This dismal survival rate compares with a 70 percent chance of children surviving other central nervous system tumors five years post diagnosis. In DIPG, tumors appear in the pons, an area of the brain that houses cranial nerve nuclei. Surgical options are limited. Spatial and temporal tumor heterogeneity is a major obstacle to accurate diagnosis and successful targeted therapy.

What’s New
The team sought to better define DIPG heterogeneity. They analyzed 134 specimens from nine patients and found that H3K27M mutations were ubiquitous in all 41 samples with oncogenic content, and always were associated with at least one partner driver mutation: TP53, PPM1D, ACVR1 or PIK3R1. These H3K27M mutations are the initial oncogenic event in DIPG, writes the research team led by Children’s National Health System. “Driver” mutations, such as H3K27M, are essential to begin and sustain tumor formation. This main driver partnership is maintained throughout the course of the disease, in all cells across the tumor, and as tumors spread throughout the brain. Because homogeneity for main driver mutations persists for the duration of illness, efforts to cure DIPG should be directed at the oncohistone partnership, the authors write. Based on early tumor spread, efforts to cure DIPG should aim for early systemic tumor control, rather focused exclusively on the pons.

Questions for Future Research
Q: If a larger sample size were analyzed, what would it reveal about the true heterogeneity/homogeneity status of DIPGs?
Q: “Accessory” driver mutations are not absolutely essential but do help to further promote and accelerate tumor growth. What is their precise role?

Source: Spatial and Temporal Homogeneity of Driver Mutations in Diffuse Intrinsic Pontine Glioma.” H. Nikbakht, E. Panditharatna, L.G. Mikael, R. Li, T. Gayden, M. Osmond, C.Y. Ho, M. Kambhampati, E.I. Hwang, D. Faury, A. Siu, S. Papillon-Cavanagh, D. Bechet, K.L. Ligon, B. Ellezam, W.J. Ingram, C. Stinson, A.S. Moore, K.E. Warren, J. Karamchandani, R.J. Packer, N. Jabado, J. Majewski, and J. Nazarian. Published by Nature Communications on April 6, 2016.

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.

Clinicopathology of diffuse intrinsic pontine glioma and its redefined genomic and epigenomic landscape

Dr. Nazarian's lab

What’s Known
Fewer than 150 U.S. children per year are diagnosed with diffuse intrinsic pontine glioma (DIPG), one of the most lethal pediatric central nervous system cancers. Despite an increasing number of experimental therapies tested via clinical trials, more than 95 percent of these children die within two years of diagnosis. Molecular studies have yielded additional insight about DIPG, including that mutations in histone-encoding genes are associated with 70 percent of cases. Understanding mutations that drive tumors and the genomic landscape can help to guide development of targeted therapies.

What’s New: Frequently found genetic alterations prevalent in DIPGs

dipg-gene-mutations-and-biological-consequences

Source: Clinicopathology of Diffuse Intrinsic Pontine Glioma and Its Redefined Genomic and Epigenomic Landscape.” E. Panditharatna, K. Yaeger, L.B. Kilburn, R.J. Packer, and J. Nazarian. Published by Cancer Genetics on May 1, 2015.