Epstein-Barr virus

Study with largest cohort in the Western world sheds light on Epstein-Barr virus

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Epstein-Barr virus

Epstein-Barr virus is a member of the herpes family and it spreads primarily through saliva.

Children’s National Hospital experts provided a contemporary description of the epidemiology, clinical presentation and management of chronic active Epstein-Barr virus (CAEBV), shedding light on this very rare disease. The paper, published in Blood Advances, assessed 57 patients outside of Asia — the biggest international retrospective cohort study published in the Western world.

Epstein-Barr virus is a member of the herpes family and it spreads primarily through saliva. Once a person is infected with Epstein-Barr virus, the immune system will control the infections, but the virus lies in a dormant state in the patient’s B Cells. However, in some patients, there is a failure of the body to control the infection, and the virus is found inside the patient’s T and/or NK cells. These rare patients are diagnosed with CAEBV. The hallmark of the disease is proliferation of Epstein-Barr virus-infected T or NK cells that infiltrate tissues, leading to end-organ damage. Patients most often experience fevers, hepatosplenomegaly, liver inflammation, cytopenias and lymphoproliferation that may progress to lymphoma.

Given it is most prevalent in Asia, little is known about the disease in the Western world. There has only been one published paper regarding the outcomes of patients in the U.S., which included 19 patients amassed over 28 years, and was published a decade ago.

Multiple treatments have been attempted to control the disease, but none have resulted in consistent remission. Historically, the consensus is to use steroids and/or antiviral drug in combination with proteasome inhibitor agents. In some cases, clinicians also use cytotoxic chemotherapy to reduce disease burden and improve the patient’s condition before HSCT. Still, this approach is limited because most patients die due to the progression of their disease despite these interventions.

Ultimately, most of these patients are referred for allogeneic hematopoietic stem cell transplantation (HSCT), which is the only known curative therapy for CAEBV. However, the best approach to control disease prior to HSCT, as well as the optimal conditioning regimen, are unknown.

“For the first time in many years, we provide insight on contemporary treatment options to consider for patients with CAEBV, as well as identifying risk factors for worse outcomes,” said Blachy Dávila Saldaña, M.D., blood and marrow transplant specialist at Children’s National and lead author of the study. “HSCT is curative, but patients need to be considered prior to the evolution of more advanced disease, particularly lymphoma. We also provide a new platform that will inform research on new interventions and therapies for this population.”

“CAEBV remains a challenging disorder to treat, especially once severe complications develop,” said Catherine Bollard, M.D., M.B.Ch.B., director of the Center for Cancer and Immunology Research at Children’s National. “However, our data suggests that T cell modulating therapies may enhance disease control, and future studies should address this question in a controlled setting.”

Future steps also include performing genetic studies to identify those at risk of developing the disease, and developing new platforms for treatment, including checkpoint inhibitors and cytotoxic lymphocyte therapies (CTL’s), which is a form of adoptive immunotherapy that employs virus-specific T cells.

The cohort includes patients treated in CNH and multiple institutions around the world, including Texas Children’s and the National Institutes of Health. “This work was only possible through our collaborative research in anti-EBV cellular therapies,” said Dr. Dávila.

t cells fighting cancer cell

Personalized T cell immunotherapy for brain tumors closer to becoming reality

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t cells fighting cancer cell

Children’s National Hospital experts developed a new approach that discovered unique proteins in an individual tumor’s cells, which then helped scientists generate personalized T cells to target and kill tumors.

Children’s National Hospital experts developed a new approach that discovered unique proteins in an individual tumor’s cells, which then helped scientists generate personalized T cells to target and kill tumors, according to a pre-clinical study published in Nature Communications.

This effort is the first to create a new workflow for neoantigen identification that incorporates both genetic sequencing and protein identification to create a personalized treatment for medulloblastoma in children, a common malignant brain tumor. Given these promising findings, the researchers are now designing a phase I clinical trial slated to open in 12-18 months.

“This work is an incredibly exciting advancement in personalized medicine. It will allow us to treat patients with a novel T cell therapy that is developed for each individual patient to specifically attack and kill their tumor,” said Catherine Bollard, M.D., M.B.Ch.B., director of the Center for Cancer and Immunology Research at Children’s National and co-senior author on the paper. “This treatment will offer a potential option for children with hard-to-treat brain tumors for which all other therapeutic options have been exhausted.”

Catherine Bollard

Catherine Bollard, M.D., M.B.Ch.B., director of the Center for Cancer and Immunology Research at Children’s National and co-senior author on the paper.

First, the researchers sequenced the DNA of small tissue samples while studying its complete set of proteins that influence cancer biology — also named a “low-input proteogenomic approach” by the authors. After analyzing the empirical data, which shies away from the commonly used predictive models, the researchers developed a T cell immunotherapy that targets the tumor’s unique proteins and allows the T cells to distinguish between healthy cells and tumor cells. This means that Rivero-Hinojosa et al. managed to merge two research fields, proteogenomics and immunotherapy, and lay the groundwork for personalized, targeted T cell therapies to treat children with brain tumors.

“Neoantigen discovery techniques have either been dependent upon in silico prediction algorithms or have required a significant amount of tumor tissue, making them inappropriate for most brain tumors,” said Brian Rood, M.D., medical director of Neuro-oncology and the Brain Tumor Institute at Children’s National. “This neoantigen identification pipeline creates a new opportunity to expand the repertoire of T cell-based immunotherapies.”

Samuel Rivero-Hinojosa

Samuel Rivero-Hinojosa, Ph.D., staff scientist at Children’s National and first author of the study.

Tumor cells have damaged DNA that create mutations during the repair process because they do not do a good job at maintaining their DNA fidelity. The repairs therefore create aberrant DNA that codes for proteins that were never intended by the genetic code and, consequently, they are unique to the individual’s tumor cells.

“We developed a new filtering pipeline to remove non-annotated normal peptides. Targeting antigens that are completely specific to the tumor, and expressed nowhere else in the body, will potentially increase the strength of tumor antigen-specific T cell products while decreasing the toxicity,” said Samuel Rivero-Hinojosa, Ph.D., staff scientist at Children’s National and first author of the study.

Once the experts identified these unique peptides, they used them to select and expand T cells, which showed specificity for the tumor specific neoantigens and the ability to kill tumor cells. The next step is to conduct a clinical trial in which a patient’s own T cells are trained to recognize their tumor’s unique neoantigens and then reinfused back into the patient.

Brian Rood

Brian Rood, M.D., medical director of Neuro-oncology and the Brain Tumor Institute at Children’s National and co-senior author on the paper.

From an immunotherapy standpoint, tumor specificity is important because when clinicians treat patients with T cell therapies, they want to make sure that the T cells directly target and kill the tumor and will not cause devastating harm to healthy cells. This paper demonstrated that it may be possible to create a better efficacy and safety margin with this new approach.

In the past five years, under the leadership of Dr. Bollard, the Center for Cancer and Immunology Research at Children’s National has advanced the scientific knowledge in preclinical and clinical settings. The center discovered a signaling pathway that can be hijacked to prevent brain tumor development, and further advanced translational research with several key first-in-human studies that utilized novel cell therapies to treat cancer and life-threatening viral infections.

Dr. Javad Nazarian

Q&A with Dr. Javad Nazarian on his upcoming work on low-grade gliomas

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Dr. Javad Nazarian

Supported by the Gilbert Family Foundation, Dr. Nazarian’s return is part of a special research program within the Gilbert Family Neurofibromatosis Institute that focuses on NF1 research.

Javad Nazarian, Ph.D., M.Sc., associate professor of Pediatrics at George Washington University and professor at the University of Zurich, has expanded his research group at Children’s National to focus on Neurofibromatosis type 1 (NF1) transformed low-grade gliomas (LGGs). Dr. Nazarian will apply his expertise from establishing a successful DIPG (diffuse intrinsic pontine glioma) and DMG (diffuse midline glioma) program in Zurich Switzerland and previously at Children’s National.

In addition to his continued research in Zurich, as a principal investigator at the Department of Genomics and Precision Medicine at Children’s National Dr. Nazarian plans on aggregating his knowledge to the new research and work spearheaded at Children’s National. As one of the first research teams to move to the Children’s National Research & Innovation Campus, Dr. Nazarian’s group is excited to use the opportunity to establish cutting-edge and clinically translational platforms.

Supported by the Gilbert Family Foundation, Dr. Nazarian’s return is part of a special research program within the Gilbert Family Neurofibromatosis Institute that focuses on NF1 research. This research includes associated gliomas with a special emphasis on NF1-associated transformed anaplastic LGGs. His team will develop new avenues of research into childhood and young adult NF-associated LGGs with a special emphasis on transformed high-grade gliomas.

Dr. Nazarian is excited for what’s to come and his goals are clear and set. Here, Dr. Nazarian tells us more about his main objectives and what it means for the future of pediatric neuro-oncology care at Children’s National.

  1. What excites you most about being back at Children’s National?

I have received most of my training at Children’s National, so this is home for me. Being one of the nation’s top children’s hospitals gives a unique advantage and ability to advocate for childhood diseases and cancers. It is always exciting to play a part in the vision of Children’s National.

  1. What are some of the lessons learned during your time working in Zurich? And how do you think these will compliment your work at Children’s National?

We developed a focused group with basic research activities intertwined with clinical needs.  The result was the launch of two clinical trials. I also helped in developing the Diffuse Midline Glioma-Adaptive Combinatory Trial (DMG-ACT) working group that spans across the world with over 18-member institutions that will help to design the next generation clinical trials. I will continue leading the research component of these efforts, which will have a positive impact on our research activities at Children’s National.

  1. How does your work focusing on low-grade gliomas formulating into high-grade gliomas expand and place Children’s National as a leader in the field?

Scientifically speaking, transformed LLGs are very intriguing. I became interested in the field because these tumors share molecular signatures similar to high-grade gliomas (HGGs). Our team has done a great job at Children’s National to develop tools – including biorepositories, avatar models, drug screening platforms, focused working groups, etc. – for HGGs. We will apply the same model to transformed LGGs with the goal of developing biology-derived clinical therapeutics for this patient population.

  1. How will this work support families and patients seeking specific neuro-oncology care?

We will develop new and high thruput tools so that we can better study cancer formation or transformation. These tools and platforms will allow us to screen candidate drugs that will be clinically effective. The main focus is to accelerate discovery, push drugs to the clinic, feed information back to the lab from clinical and subsequently design better therapies.

  1. You are one of the first scientists to move to the Children’s National Research & Innovation Campus. What are some of the valuable changes or advancements you hope to see as a result of the move?

The campus will provide high-end facilities, including cutting-edge preclinical space, and allow for team expansion. The close proximity to Virginia Tech will also provide an environment for cross-discipline interactions.

  1. Anything else you think peers in your field should know about you, the field or our program?

The team at Children’s National includes Drs. Roger Packer and Miriam Bornhorst. Both have provided constant clinical support, innovation and clinical translation of our findings. I look forward to working with them.

Hodgkin lymphoma cells

T-cell therapy alone or combined with nivolumab is safe and persistent in attacking Hodgkin’s lymphoma cells

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Hodgkin lymphoma cells

Hodgkin’s lymphoma is a type of cancer that attacks part of the immune system and expresses tumor-associated antigens (TAA) that are potential targets for cellular therapies.

It is safe for patients with relapsed or refractory Hodgkin’s lymphoma (HL) to receive a novel tumor-associated antigen specific T-cell therapy (TAA-T) either alone or combined with a checkpoint inhibitor, nivolumab — a medication used to treat several types of cancer. The study, published in Blood Advances, further suggests that nivolumab aids in T-cell persistence and expansion to ultimately enhance anti-tumor activity. This offers a potential option for patients who do not have a durable remission with checkpoint inhibitors alone or are at a high risk of relapse after a transplant.

“The fact that this combination therapy is so safe was very encouraging for the treatment of patients with lymphomas,” said Catherine Bollard, M.D., M.B.Ch.B., director of the Center for Cancer and Immunology Research at Children’s National Hospital. “In addition, this data allows us to consider this combination immunotherapy for other patients, including those with solid tumors.”

HL is a type of cancer that attacks part of the immune system and expresses tumor-associated antigens (TAA) that are potential targets for cellular therapies. While it may affect children and adults, it is most common in those who are between 20 and 40 years old. The survival rate for this condition has improved due to scientific advances.

A new approach in cancer therapy is the use of “checkpoint inhibitors,” which are a class of drugs that block some of the inhibitory pathways of the immune system to unleash a powerful tumor killing immune response. Similarly, T-cell therapies have also shown to enhance anti-tumor immune response. Therefore, combining these novel immune therapies is an attractive and targeted alternative to conventional untargeted therapies – such as chemotherapy and radiation – which not only kill the tumor cells but also can kill healthy cells and tissues.

“In five to 10 years we can get rid of chemotherapy and radiation therapy and have an immunotherapy focused treatment for this disease,” said Dr. Bollard.

To determine the safety of infusing TAA-T with and without checkpoint inhibitors, eight patients were infused with TAA-specific T-cell products manufactured from their own blood. Two other patients received TAA-T generated from matched healthy donors as adjuvant therapy after hematopoietic stem cell transplant. According to Dave et al., the TAA-T infusions were safe and patients who received TAA-T as adjuvant therapy after transplant remained in continued remission for over two years.

Of the eight patients with active disease, one patient had a complete response, and seven had stable disease at three months, three of whom remained with stable disease during the first year.

“Treating Hodgkin’s lymphoma with cellular therapy has not yet achieved the same success that we have seen for other lymphoma subtypes,” said Keri Toner, M.D., attending physician at Children’s National. “This study brings us closer to overcoming some of the current barriers by developing methods to improve the persistence and function of the tumor-specific T-cells.”

This study builds upon the researchers’ latest findings in another study, which demonstrated that TAA-T manufactured from patients were safe and associated with prolonged time to progression in solid tumors.

“The addition of a checkpoint inhibitor like Nivolumab to the TAA-T treatment is a powerful next step, but previously, the safety of this combination was unknown,” said Patrick Hanley, Ph.D., chief and director of the Cellular Therapy Program at Children’s National, leader of the GMP laboratory and co-author of the study. “Now that we have demonstrated a safety profile, the next step will be to evaluate the efficacy of this combination in a larger subset of patients.”

Sickle-Cell-Blood-Cells

Children’s National joins ASH RC Sickle Cell Disease Clinical Trials Network

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Sickle-Cell-Blood-Cells

The American Society of Hematology Research Collaborative (ASH RC) has announced the first 10 clinical research consortia to join the ASH RC Sickle Cell Disease Clinical Trials Network. Children’s National Hospital will be one of the clinical trials units to serve in the DMV Sickle Cell Disease Consortium (DMVSCDC).

The sites will be able to enroll children and adults living with sickle cell disease (SCD) within their patient populations in clinical trials as part of an unprecedented national effort to streamline operations and facilitate data sharing to expedite the development of new treatments for this disease.

“As part of the ASH RC SCD clinical trials network, we will learn regionally and nationally how sickle cell patients respond differently to therapies, hopefully giving us clues to provide more successful targeted and individualized treatments that will improve the morbidity and mortality in sickle cell disease patients,” said Andrew Campbell, M.D., director of Comprehensive Sickle Cell Disease Program at Children’s National.

SCD is a chronic, progressive, life-threatening, inherited blood disorder that affects more than 100,000 Americans and an estimated 100 million persons worldwide. Clinical trials hold incredible promise for the development of much-needed new treatments, and possibly even a cure. While there are currently only four U.S. Food and Drug Administration (FDA)-approved drugs to treat the disease, there is a robust SCD drug development pipeline that will drive demand for clinical trials to a new level, providing a prime opportunity to advance treatment and care of those affected by SCD.

“We are proud that the DMV Sickle Cell Disease Consortium will contribute regionally, allowing our patients and families to benefit from new clinical trials investigating new therapies that may improve the clinical course and quality of life of patients living with sickle cell disease in the DMV region,” Dr. Campbell added. “We will also have an integrated Community Advisory Board who will continue to provide guidance and expertise for our consortium including patients, families and caregivers.”

Read the full list of other hospitals joining the network.

A transient low-dose MEKi treatment in a pre-clinical model prevents NF1-OPG formation

Using targeted signaling pathway therapy to prevent pediatric glioma formation

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Researchers at Children’s National Hospital identified a vulnerability in a developmental signaling pathway that can be hijacked to drive pediatric low-grade glioma (pLGG) formation, according to a pre-clinical study published in Developmental Cell. The study demonstrated that targeted treatment prevents tumor formation, long before irreversible damage to the optic nerve can cause permanent loss of vision. This finding will inform chemo-prevention therapeutic trials in the future.

Brain tumors are the most common solid tumors in children, the most prevalent of which are pLGGs. Approximately 10% to 15% of pLGGs arise in patients with the familial cancer predisposition syndrome known as neurofibromatosis type 1 (NF1). This is a genetic condition that increases risks of developing tumors along the nerves and in the brain.

Nearly 20% of children with NF1 develop pLGGs along the optic pathway, also known as NF1-associated optic pathway glioma (NF1-OPG). Despite many advances in cancer therapy, there are no definitive therapies available that prevent or alleviate the neurological deficits (i.e. vision loss) and that could improve the quality of life.

“The evidence presented can inform chemoprevention therapeutic trials for children with NF1-OPG,” said Yuan Zhu, Ph.D., scientific director and Gilbert Family Endowed professor at the Gilbert Family Neurofibromatosis Institute and associate director of the Center for Cancer and Immunology Research, both part of Children’s National. “This therapeutic strategy may also be applicable to children with the developmental disorders that are at high risk of developing pediatric tumors, such as other RASopathies.”

The mechanism of vulnerability to pLGGs during development is not fully understood. It has been implied that the cell population of origin for this debilitating tumor is transiently proliferative during development. The NF1 gene produces a protein that helps regulate normal cell proliferation, survival and differentiation by inhibiting MEK/ERK signaling. When there is loss of function in NF1, it abnormally activates the MEK/ERK signaling pathway and leads to tumor formation.

Certain cells that exist transiently during the normal development of the brain and optic nerve are vulnerable to tumor formation because they depend on the MEK/ERK signaling. In this study, researchers in Zhu’s lab identified cells that were MEK/ERK pathway dependent and grew during a transient developmental window as the lineage-of-origin for NF1-OPG in the optic nerve. The researchers used a genetically engineered pre-clinical model to design a transient, low-dose chemo-preventative strategy, which prevented these tumors entirely.

“When we provided a dose-dependent inhibition of MEK/ERK signaling, it rescued the emergence and increase of brain lipid binding protein-expressing (BLBP+) migrating GPs glial progenitors, preventing NF1-OPG formation,” wrote Jecrois et al. “Equally importantly, the degree of ERK inhibition required for preventing NF1-OPG formation also greatly improved the health and survival of the NF1-deficient model.”

Ongoing clinical trials using MEK inhibitors (MEKi) are being performed for children as young as 1 month old. Thus, it becomes increasingly feasible to design a chemo-preventative trial using a MEKi to treat children with NF1. These treatment paradigms may have the potential to not only prevent OPG formation, but also other NF1-associated and RASopathies-associated developmental defects and tumors.

A transient low-dose MEKi treatment in a pre-clinical model prevents NF1-OPG formation

A transient low-dose MEKi treatment in a pre-clinical model prevents NF1-OPG formation. The middle panels highlighted by a red dashed box show an OPG in the optic nerve (arrows, top), exhibiting abnormal triply-labeled tumor cells, inflammation and nerve damage (the bottom three panels), which are absent in the normal (left panels) or MEKi-treated Nf1-deficient optic nerves (right panels). [Credit: Jecrois et al., Developmental Cell, (2021)]

Yuan Zhu

Yuan Zhu, Ph.D., receives Outstanding Scientist Award

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Yuan Zhu

The George Washington University (GW) Cancer Center recently announced the selection of the 2021 GW Cancer Center Awards, recognizing excellence in research, mentorship and early career contributions.

The GW Cancer Center Outstanding Scientist Award was presented to Yuan Zhu, Ph.D., professor of pediatrics at the GW School of Medicine and Health Sciences (SMHS) and Children’s National Hospital. The award is presented to faculty members who make a noteworthy contribution in the areas of basic science, clinical science, translational science or population science.

In his nomination, Dr. Zhu was cited for his contributions to the understanding of the mechanisms underlying the development of tumors and altered brain development arising in the setting of the inherited condition neurofibromatosis type 1 (NF1). “Throughout his career, Dr. Zhu has had a remarkable consistency of focus in his scholarly work, where he has sought to advance new molecular and mechanistic insights to understand the biological basis of NF1 and the cancers arising in individuals affected by this genetic disease.”

You can find a full list of award winners here.