Neuroblastoma relapse is one of the greatest challenges to complete cure for children with high-risk disease. At least 40% of high-risk neuroblastoma patients will experience cancer relapse 4 years after intense treatment, which includes a combination of chemotherapy, surgery, irradiation and the self-transplantation of stem cells (consolidation therapy).
To overcome this problem improved maintenance therapy is needed. These are therapies administered to patients after the end of the initial treatment to prevent tumour relapse. Frequently, maintenance therapy for neuroblastoma includes immunotherapies such as antibodies against GD-2 and cytokines and 13-cis-retinoic acid. Although these therapies have some positive effects, the rate of relapse is still high. Therefore, other options to prevent relapse are needed.
Recently, a phase II clinical trial evaluated the effect of Difluoromethylornithine (DFMO) on event-free survival (EFS) and overall survival (OS) of high-risk neuroblastoma patients1. Event-free survival means the length of time that the patient remains free of cancer after the end of treatment, while overall survival means the length of time that the patient is alive after the diagnosis or the start of treatment. The measurement of event-free survival and overall survival provides a good indication of the treatment effect.
In this clinical trial report the therapy efficacy on 81 patients that received immunotherapy treatment with dinutuximab and started DFMO maintenance therapy at least 120 days after completion of treatment were compared to the efficacy (based on medical records) from a group of 76 patients that got the same treatment but without the maintenance with DFMO.
DFMO inhibit the ornithine decarboxylase pathway, which is related to cell growth and decreased cell death, thus preventing cells to become cancerous and tumour progression. The results demonstrated that maintenance therapy with DFMO provided 85% of 5-year event-free survival compared to 65% for no-DFMO maintenance therapy, and 95% 5-year OS compared to 81% no-DFMO therapy2.
In conclusion, this study results suggest a benefit provided by the DFMO therapy in preventing neuroblastoma relapse. The researchers suggest that early therapy with DFMO may further improve these results. Therefore, more clinical trials evaluating this possibility are being conducted3,4.
Written by Luiza Erthal
References
1. SaulnierSholler, G. A Phase II Preventative Trial of DFMO (Eflornithine HCl) as a Single Agent in Patients With High Risk Neuroblastoma in Remission. https://clinicaltrials.gov/ct2/show/NCT02395666 (2020).
2. Lewis, E. C. et al. A subset analysis of a phase II trial evaluating the use of DFMO as maintenance therapy for high‐risk neuroblastoma. Int. J. Cancer 147, 3152–3159 (2020).
3. SaulnierSholler, G. Phase II Trial of Eflornithine (DFMO) and Etoposide for Relapsed/Refractory Neuroblastoma. https://clinicaltrials.gov/ct2/show/NCT04301843 (2021).
4. SaulnierSholler, G. NMTT- Neuroblastoma Maintenance Therapy Trial Using Difluoromethylornithine (DFMO). https://clinicaltrials.gov/ct2/show/NCT02679144 (2021).
Immunotherapies are treatments that stimulate the patient’s immune system to help it to fight cancer. This type of treatment is gaining more attention in neuroblastoma due to the possibility to combine it with other therapies, potentially, generating fewer side effects.
Clinical trials are research protocols performed in patients to evaluate whether a new treatment is safe and effective. This type of research can also compare standard treatments with new treatment options as well as investigate new combinations of drugs. Clinical trials occur in phases comprising phase I (safety), phase 2 (safety and efficacy), phase 3 (safety, efficacy and comparison with standard treatments for the specific disease).
According to a search performed on November 14th, 2021, there are 594 clinical trials for neuroblastoma at clinicaltrials.gov, a clinical trial database from the United States (US). From these, 173 are recruiting or active trials and 15 are related to immunotherapies. Generally, these are initial trials evaluating treatment combinations using chemotherapy, cell transplants and immunotherapy, including antibodies and vaccines.
Trials for antibodies
The most explored target for immunotherapy in neuroblastoma is the GD2, a molecule present in the surface of neuroblastoma cells that can be used to combat the tumour. Indeed, antibodies that bind to GD2 called dinutuximab and naxitamab are approved for use in the US to treat neuroblastoma1,2.
A clinical trial in the US and Canada is recruiting patients to evaluate the combination of dinutuximab with another antibody called Magrolimab in patients with neuroblastoma that do not respond to or come back after treatment3. This is an initial trial (Phase 1), which aims to determine the best doses and side effects of this combination.
Racotumomab, an antibody that binds to N-glycolyl GM3, a molecule that is highly expressed in the surface of neuroblastoma cells, is being evaluated in high-risk neuroblastoma5. The study aims to determine the immune response generated by the drug and the related toxicity.
Trials for vaccines
A trial from Dana-Farber Cancer Institute is recruiting patients to study the GVAX Vaccine and its combination with the antibodies, nivolumab and ipilimumab, that stimulates T-cells to attack the cancer 6. The vaccine is produced with neuroblastoma cells from the patient. The study will evaluate the dose and safety of the combination treatment.
Another trial is evaluating the use of a modified neuroblastoma cell vaccine in combination with low doses of chemotherapy (Cytoxan/Cyclophosphamide)7. A vaccination scheme comprising 8 doses of vaccine and cycles of oral chemotherapy is planned and patients will be closely monitored through the vaccination period to evaluate side effects and disease status. This study is ongoing and will follow the patients for 15 years after completing the vaccination scheme.
Trials for cell therapy
A trial evaluating the use of modified T-cells (CART-T-cell) to recognise GD2- neuroblastoma cells in combination with chemotherapies (cyclophosphamide and fludarabine) and an antibody (Pembrolizumab) is ongoing8. The combination is based on previous studies that have demonstrated the longer time presence of CAR T-cell in the blood of patients after intravenous infusion of chemotherapy. Moreover, the antibody will help to stimulate the patient immune system. The trial aims to determine the highest dose possible for the combination treatment generating fewer side effects.
Another Phase I immunotherapy trial for neuroblastoma aims to compare the treatment with dinutuximab and lenalidomide (drugs that support the immune system) and Natural Killer (NK) cells from the patient9. The NK cells can kill cancer cells while the two immunotherapeutic drugs activate the NK cells. This study will determine the safest dose of cells to be used in combination with the drugs.
Conclusion
Considering some of the clinical trials in progress that uses immunotherapy to treat neuroblastoma, we can conclude that this therapy modality holds great promise to advance and potentially serve as a new treatment option to improve neuroblastoma patients’ survival and quality of life.
Written by Luiza Erthal
References
1. Drugs Approved for Neuroblastoma – National Cancer Institute. https://www.cancer.gov/about-cancer/treatment/drugs/neuroblastoma (2011).
2. Memorial Sloan Kettering Cancer Center. Expanded Access Use of Naxitamab/GM-CSF Immunotherapy for Consolidation of Complete Remission or Relapsed/Refractory High-Risk Neuroblastoma. https://clinicaltrials.gov/ct2/show/NCT04501757 (2021).
3. National Cancer Institute (NCI). Phase 1 Trial of Hu5F9-G4 (Magrolimab) Combined With Dinutuximab in Children and Young Adults With Relapsed and Refractory Neuroblastoma or Relapsed Osteosarcoma. https://clinicaltrials.gov/ct2/show/NCT04751383 (2021).
4. Memorial Sloan Kettering Cancer Center. Hu3F8/GM-CSF Immunotherapy Plus Isotretinoin for Consolidation of First Remission of Patients With High-Risk Neuroblastoma: A Phase II Study. https://clinicaltrials.gov/ct2/show/NCT03033303 (2020).
5. Laboratorio Elea Phoenix S.A. Open-label, Multicenter, Phase II Immunotherapy Study With Racotumomab in Patients With High-risk Neuroblastoma. https://clinicaltrials.gov/ct2/show/NCT02998983 (2021).
6. Collins, N. B. A Phase 1 Study of Combination Nivolumab and Ipilimumab With Irradiated GM-CSF Secreting Autologous Neuroblastoma Cell Vaccine (GVAX) for Relapsed or Refractory Neuroblastoma. https://clinicaltrials.gov/ct2/show/NCT04239040 (2021).
7. Heczey, A. A Phase I/II Study Using Allogeneic Tumor Cell Vaccination With Oral Metronomic Cytoxan in Patients With High-Risk Neuroblastoma (ATOMIC). https://clinicaltrials.gov/ct2/show/study/NCT01192555 (2021).
8. Heczey, A. Autologous Activated T-Cells Transduced With A 3rd Generation GD-2 Chimeric Antigen Receptor And iCaspase9 Safety Switch Administered To Patients With Relapsed Or Refractory Neuroblastoma (GRAIN). https://clinicaltrials.gov/ct2/show/NCT01822652 (2021).
9. New Approaches to Neuroblastoma Therapy Consortium. A Phase I Dose Escalation Study of Autologous Expanded Natural Killer (NK) Cells for Immunotherapy of Relapsed Refractory Neuroblastoma With Dinutuximab +/- Lenalidomide. https://clinicaltrials.gov/ct2/show/NCT02573896 (2021).
The determination of the tumour stage is an important step after a neuroblastoma diagnosis. The stage of neuroblastoma is determined depending on tumour location and if it has spread to other parts of the body. This will guide risk group assignment and treatment choice.
The first staging system for neuroblastoma, the International Neuroblastoma Staging System (INSS), was developed in 1986 and is based on the pathological evaluation of the tumour after a removal surgery. In 2005, The International Neuroblastoma Risk Group Staging System (INRGSS) started to be used. This system is based on tumour images before any surgery. Therefore, it is based on image-defined risk factors to determine the tumour stage (see table below). It also uses clinical, pathologic, and genetic markers to determine the risk groups, which can be low-risk, intermediate-risk, or high-risk.
Reference: Neuroblastoma – Childhood: Stages and Groups, Cancer.net.
Recently, the Children’s Oncology Group (COG), a clinical trial group dedicated to paediatric cancer research revised the classification system they use to determine tumour stage for enrolment in clinical trials1. Previously, they have been defining the tumour stage based on the INNS system. Now they proposed a revised classification that takes into account the INRGSS and chromosomal alterations.
Key clinical and biological factors used in the neuroblastoma risk classification include age at diagnosis, disease stage, tumour tissue appearance under a microscope (histology), the status of the gene MYCN that affects tumour growth, the amount of DNA in a tumour cell (called tumour cell ploidy), and alterations in the DNA.
They analyse the outcome of almost 5,000 patients to define risk groups based on the INRGSS, using alterations in the DNA of tumour cells as a biomarker and considering current therapy modalities. In general, they found that the correlation of stages between systems is not exact. However, the differences in survival were minimal when comparing staging systems, which corroborates the use of the revised version.
In general, the new version classifies L1 and L2 tumours as low risk, except for L1 tumours with alteration in the gene MYCN and that cannot be removed by surgery, which is high-risk. For L2 tumours, MYCN status and age can be used to evaluate prognosis. Stage M tumours can be classified as high risk or intermediate-risk depend on age, MYCN status and DNA alterations. In conclusion, low-risk groups have excellent outcomes with any or limited therapy, the intermediate-risk group have very good outcomes and high-risk groups have inferior outcomes despite therapy.
This new version of the COG classifier will provide a uniformization of patient risk classification for clinical trials, ultimately enabling the comparison between different trials.
Written by Luiza Erthal
Reference:
1. Irwin, M. S. et al. Revised Neuroblastoma Risk Classification System: A Report From the Children’s Oncology Group. J. Clin. Oncol. JCO.21.00278 (2021)
For most neuroblastoma cases a tissue biopsy, which means remove a piece of the tumour and analyse under a microscope, is performed to confirm the diagnosis, allow the risk stratification (low, intermediate or high-risk cancer) and determine treatment. However, it is not always possible to perform a biopsy. In these cases, other tests are available such as ultrasound, x-ray and urine test1. Although these tests help the diagnostic, they are much less informative to determine the risk group and to guide treatment.
Cancer is a genetic disease and as such several genetic alterations are present in the DNA and can be useful to determine a diagnostic and prognostic of the disease. These alterations can also be useful to monitor treatment effects. But, how we can examine the DNA without using a piece of the tumour?
The answer for that relies on our blood. Cancer patients have cancer cells circulating in their blood and these cells release what we call cell-free tumour DNA. The level of cell-free tumour DNA in the blood of a healthy individual is low while this is increased in cancer patients. The detection of cell-free tumour DNA with specific alterations may help to not only detect the disease but also determine if the tumour cells are changing after treatment.
Recently, a trial for a blood test that can detect 50 different types of cancer was launched in the UK2. The test called the Galleri test look for cell-free tumour DNA in the blood using modern genetic sequencing technology. It spots the DNA that has changes common in specific cancers but not seen in healthy cells.
One of the main questions of this trial is if the test can find early stages of cancers. Although neuroblastoma is cancer that could benefit from this test, unfortunately, it is not one of the cancer types detected. However, the presence of cell-free tumour DNA was already detected in neuroblastoma patients’ blood3. Moreover, several alterations in the DNA of neuroblastoma patients have already been reported to have predictive value for disease progression and treatment monitoring. These alterations include the increase in the number of specific genes, genes breakdown or increased activity of certain genes. Their presence may indicate poor outcomes and early detection could guide to specific treatment options.
The big challenge is to have a non-invasive diagnostic method, such as blood tests, that are sensitive enough to detect the early stages of the disease. Specifically for neuroblastoma, comprehensive analysis in clinical trials regarding cell-free DNA levels and their specific changes over time would help to advance the development of liquid biopsies, such as blood tests, for this type of tumour.
We are launching a new initiative #AskLuiza to help the public and patients know more about advances and current trends in neuroblastoma.
Luiza is a research writer at the Cancer Bioengineering Research Group. She holds a PhD in Biomedical Sciences from Trinity College Dublin. You will ask a question and Luiza will look for the answer in peer-reviewed research papers that the research community trust.
Finding suitable research models to study disease is a big challenge for researchers around the world. In cancer research, it is essential to work with models that can recapitulate tumour characteristics as much as possible. This is important to test chemotherapeutic drugs, understand tumour behaviour and have higher chances of translating the finds from the laboratory to clinical practice.
Multiple factors influence tumour behaviour and disease progression. The most important is the tumour microenvironment, which comprises different cells and molecules that surround the tumour and the extracellular matrix, a network of molecules that provides support to the cells in the body.
Most cell studies in a laboratory are based on 2D cell culture models in which the cells grow in a monolayer. Although this approach has a low cost and it is easy to use, it lacks the complexity observed in the clinical scenario. It is true that no model can recapitulate all the complexity found in the body. However, scientists were able to develop interesting approaches to study different tumour characteristics with relatively good approximation1.
Specifically for neuroblastoma, the most common solid tumour that affects children, scientists developed 3D models in which neuroblastoma cells grow interacting with the surrounding environment and with each other in a vial. Examples of 3D models include cells grown in hydrogels or scaffolds and multicellular tumour spheroids (see image below). Spheroids are formed through the self-adhesion of tumour cells growing in the form of very small balls. They can be maintained in the laboratory on their own or supported by scaffold-based platforms (jelly-like or porous materials). Scaffolds essentially support the cell resembling the extracellular matrix and surrounding tissue in the body.
Credits for the image: 3D models to study neuroblastoma. Adapted from Nolan, J. C. et al. Preclinical models for neuroblastoma: Advances and challenges. Cancer Lett. 474, 53–62 (2020).
In the Cancer Bioengineering Research Group, we work with neuroblastoma models such as organoids, a more complex type of spheroid, to understand neuroblastoma migration and invasion2. Moreover, we recently shared with the research community a protocol at jove.com describing the development of a 3D neuroblastoma model using collagen-based scaffolds3.
Time-lapse video of neuroblastoma organoids’ growth. Accompanying experimental data published in Gavin et al., Cancers 2021. Source: the Cancer Bioengineering Research Group
These models have the potential to advance drug tests performed in the laboratory providing better clinical translation, ultimately contributing to improving the quality of life and survival of children diagnosed with neuroblastoma.
The work with 3D models at the Cancer Bioengineering Research Group is supported by the Irish Research Council, the Conor Foley Neuroblastoma Cancer Research Foundation, Neuroblastoma UK and National Children’s Research Centre.
Written by Luiza Erthal
References
1. Nolan, J. C. et al. Preclinical models for neuroblastoma: Advances and challenges. Cancer Lett.474, 53–62 (2020).
2. Gavin, C. et al. Neuroblastoma Invasion Strategies Are Regulated by the Extracellular Matrix. Cancers13, 736 (2021).
3. Gallagher, C., Murphy, C., O’Brien, F. J. & Piskareva, O. Three-dimensional In Vitro Biomimetic Model of Neuroblastoma using Collagen-based Scaffolds. J. Vis. Exp. 62627 (2021) doi:10.3791/62627.
And the story began with a meeting of fantastic 7 at the very beginning of Dublin Mountains Way in Tallaght at 6.30 am on September 25th. The spirit, cheer, backpacks with essentials and branded tops were on, Strava was launched and we swiftly headed off.
It was quiet, dark and cheering. No one was on the streets, a few cars passed by. We took towards Bohernabreena reservoir through the sleepy estates of Tallaght, sensing the sunset. Clouds were low and the highest peaks in the Dublin Mountains including Seefingan, Corrig and the highest, Kippure were in the mist. Nevertheless, we were full of energy and hopes to see it later.
Cheat chats and jokes were here and there, we walked in small dynamic groups recalling our pre-covid life and stories that happened during the lockdown. A mix of newbies and maturating research students. We met some in person for the first time since the COVID restrictions admitting that our visual senses are extremely important to memorise a person and recognise him/her on the next occasion. We were enjoying this face-to-face communication and our team re-connection.
The first 8 km flew in a flash. We stopped for our breakfast in Dublin Mountains. The grass was wet, the sky was blue. Mountains started to draw their shape through the clouds. Yoghurts, fruits, bars immediately disappeared in our stomachs. Everyone was happy to lighten their backpack. Every little helps!
A few plasters were glued, and we continued on at a very good pace. The sky was changing with sunny spells. We travelled around Spinkeen and Killakee at their base doing up and downhills and verifying our route with the hiking app. At the 20 km mark, we stopped for lunch. Sandwiches, grapes, mandarines and sweets were shared and eaten and then polished with chocolates from the recent Nadiya’s home trip. Jellies left untouched.
At 25 km, our blisters reminded us of being humans. Our pace slowed down and we started a very mild ascent to Tibradden Mountain leaving the Pine Forest or Tibradden Wood behind. We climbed further to Fairy Castle, the highest point on the Dublin Mountains Way (537m). Throughout the entire way, Dublin showed its best views of the Phoenix Park and the Pope Cross, house roofs, Aviva Stadium, two Chimneys, Dublin Port… The scenery was fascinating and breathtaking. We saw Howth and Dun Laoghaire, Sugar Loaf… We met groups of Germans, French, Irish and many others.
At Three Rocks Mountain/Fairy Castle, we started our descent and entered Tiknock forest. This part was steep. We crossed the Gap Mountain Bike Adventure Park to reach Glencullen. Got lost at the end but just for a sec and reached the Glencullen junction at 2.30pm. It took us 8 hours with walks and stops from start to finish to complete the 30 km challenge in a day. We got tired but felt happy and satisfied.
We aimed to raise awareness of childhood cancer in general and neuroblastoma in particular as well as honour children with cancer, their parents, siblings, friends and careers, doctors and nurses, volunteers in the hospitals and researchers working to find cancer weaknesses and develop new treatments that are friendly to patients and target cancer aggressiveness.
We will count our tally in the coming days and transfer it to three wonderful charities that support childhood cancer research.
I’m Ronja, I’m from Germany, but have spent my entire adult life in the English-speaking parts of this world. Right after school, I interned with a PhD student working on cystic fibrosis for a couple of months. Having the chance to culture airway epithelial cells myself made me certain I was on the right track with biomedical sciences. So, I studied Biomedical Sciences (Anatomy) in Aberdeen. The best part of that degree was my introduction to dissections. I enjoyed them so much that I even considered becoming a full-time prosector. But that does not count as essential work, so I found a remote master’s degree in Health Research instead. Studying remotely gave me the fabulous opportunity to structure my own time. I could go and explore Scotland during the day and work in the evenings. But after 5 years of studying, I was finally ready to start a PhD and was ever so delighted when I heard I could weave in some dissections at RCSI. Now, I’m looking forward to discovering what Dublin has to offer and to getting stuck in my research project!
While I didn’t know much about the particulars of my PhD before starting, I had an idea about the project from the application and I knew accommodation was sorted out for me, but I had never seen the place or my future flatmates. The one thing that I was made aware of far in advance of moving to Dublin was that September was Child Cancer Awareness Month, for which the team was going to do a charity event. Based on past years I was expecting it to be a 10km run, which was pretty daunting to me. So, I prepared. I started running and cycling over the summer until 10km weren’t an issue anymore. But in the first lab meeting plans shifted. We were going to do the Dublin Mountains Way in a day. The 10km were tripled and depending on donations maybe even quadrupled. Quite a different challenge! But I believe my summer prepared me well for that too. Alongside running I started cycling a little as well. And because there was a free bike in Aberdeen for me, I cycled it down to Stirling. Let’s hope that the endurance needed to cycle 200km translate to hiking 30-42km!
Here are our plans. This year we have upped the challenge, taking on the Dublin Mountain’s Way in a Day ⛰ We will hike through the Dublin Mountains from Tallaght to Glencullen, and maybe even all the way to Shankill on September 25th! Our challenge is not only to do #DMW in a Day & support three wonderful charities CMRF Crumlin/National Children’s Research Centre, Neuroblastoma UK and the Conor Foley Neuroblastoma Cancer Research Foundation but also beat our past fundraising records! If we raise 2K+, we’ll do 30km in a day. If 3K+ then 42km! Can u challenge us? All funds raised will go to the 3 selected charities. Every donation big or small is hugely appreciated!
Every 100th cancer patient is a child. Cancer is the 2nd most common cause of death among children after accidents.
Childhood cancer is an umbrella term for many other types of this disease. Every September, many charities, researchers and parents of children with cancer work hard to raise awareness of this cancer. You may learn more about kids with cancer, their loving families, the doctors and caregivers who looking after them and treating them, the young survivors of cancer and those kids and teens who lost their battle, and the scientists who working hard to find a way to stop childhood cancer.
This year our research team will hike Dublin MountainWay in One Day on the 25th of September 2021 whatever the weather in honour of Childhood Cancer Awareness Month. For every one euro donated to research only 1 cent of this goes to ALL childhood health conditions including cancer. Therefore, the donations we receive will be split equally among some wonderful children’s charities. These charities include the Conor Foley Neuroblastoma Research Foundation (CFNRF), Neuroblastoma UK (NBUK), Children’s Research & Medical Foundation (CRMF) Crumlin.
If you would like to get involved in this amazing challenge and help us raise vital funds for childhood cancers, you can contribute to our fundraising page:
