Immune-Based Approaches for the Treatment of Pediatric Malignancies

Critical Partnerships: How to Develop a Trans-Disciplinary Research Team

Trans-disciplinary science will continue to be critical for the next wave of scientific advancement to fully understand cancer development, progression, and treatment. The shift from the independent investigator to either leading or being a productive member of a scientific team can be successful by focusing on some key elements that can build and strengthen interactions with a diverse group of people. These include the selection of the team, communication, leadership and mentorship, shared goals, responsibility to the team, authorship, and proactively dealing with conflict. While there are extensive books written on developing teams in the business world, and larger pieces in the medical arena, we attempt to provide here a concise, high-level view as a starting point for those that may be moving from being an independent researcher and are developing their own, larger, trans-disciplinary teams.

Dental caries and dental developmental defects as adverse effects of antineoplastic treatment in childhood cancer survivors

PURPOSE

To evaluate the prevalence of dental caries and dental developmental defects (DDD) in childhood cancer survivors (CCS) and identify disease and treatment-related risk factors.

METHODS

CCS aged up to 21 years, diagnosed with a malignancy before the age of 10 years and in remission for at least one year were included. Data were collected from patients' medical records and through a clinical examination where presence of dental caries and prevalence of DDD were recorded. Fisher's exact test was used to assess possible correlations and multivariate regression analysis to determine risk factors for defect development.

RESULTS

Seventy CCS with a mean chronological age of 11.2 years at the time of examination, mean age at cancer diagnosis of 4.17 years, and a mean post-treatment follow-up time of 5.48 years were included. Mean DMFT/dmft was 1.31, with 29% of survivors presenting with at least one carious lesion. Younger patients on the day of examination and patients treated with higher radiation dose, showed significantly higher prevalence of dental caries. The prevalence of DDD was 59%, with demarcated opacities being the defect most commonly observed (40%). Age at dental examination, diagnosis, age at diagnosis, and time that have elapsed since the end of treatment were the factors significantly affecting its prevalence. Regression analysis revealed that age at examination was the only factor significantly associated with the presence of coronal defects.

CONCLUSION

A great number of CCS presented with at least one carious lesion or a DDD, with the prevalence being significantly associated with various disease-specific characteristics, but age at dental examination the only significant predictor.

Association of race/ethnicity with innate immune tumor microenvironment of children with B-acute lymphoblastic leukemia

BACKGROUND

Black and Hispanic children with B-acute lymphoblastic leukemia (B-ALL) experience worse outcomes compared with their non-Hispanic white (NHW) counterparts. Immune-based approaches have begun to transform the therapeutic landscape in children with B-ALL. Recent studies identified several alterations in both innate and adaptive immune cells in children with B-ALL that may impact disease risk and outcome. However, the impact of racial/ethnic background on immune microenvironment is less studied, as children of minorities background have to date been severely under-represented in such studies.

METHODS

We performed high-dimensional analysis of bone marrow from 85 children with newly diagnosed B-ALL (Hispanic=29, black=18, NHW=38) using mass cytometry with 40 and 38-marker panels.

RESULTS

Race/ethnicity-associated differences were most prominent in the innate immune compartment. Hispanic patients had significantly increased proportion of distinct mature CD57 +T-bet+DR+ NK cells compared with other cohorts. These differences were most apparent within standard risk (SR) patients with Hispanic SR patients having greater numbers of CD57 +NK cells compared with other cohorts (43% vs 26% p=0.0049). Hispanic and Black children also had distinct alterations in myeloid cells, with a significant increase in a population of non-classical activated HLA-DR +CD16+myeloid cells, previously implicated in disease progression, compared with NHW counterparts. Racial background also correlated with altered expression of inhibitory checkpoint PD-L1 on myeloid cells.

CONCLUSION

There are surprisingly substantial race/ethnicity-based differences in innate immune cells of children with newly diagnosed B-ALL. These differences urge the need to enhance accrual of children from minorities background in immunetherapy trials and may impact their outcome following such therapy.

Polyendocrine Autoimmunity and Diabetic Ketoacidosis Following Anti-PD-1 and Interferon α

Immune checkpoint inhibitor (ICI) therapies are now first-line therapy for many advanced malignancies in adults, with emerging use in children. With increasing ICI use, prompt recognition and optimal management of ICI-associated immune-related adverse events (IRAEs) are critical. Nearly 60% of ICI-treated adults develop IRAEs, which commonly manifest as autoimmune skin, gastrointestinal, and endocrine disease and can be life-threatening. The incidence, presentation, and disease course of spontaneous autoimmune diseases differ between adults and children, but the pattern of pediatric IRAEs is currently unclear. We report a case of a pediatric patient presenting with new onset autoimmune diabetes mellitus and diabetic ketoacidosis during ICI treatment of fibrolamellar hepatocellular carcinoma (FLC). Distinct from spontaneous type 1 diabetes mellitus (T1DM), this patient progressed rapidly and was negative for known β cell autoantibodies. Additionally, the patient was positive for 21-hydroxylase autoantibodies, suggesting development of concomitant adrenal autoimmunity. Current guidelines for the management of IRAEs in adults may not be appropriate for the management of pediatric patients, who may have different autoimmune risks in a developmental context.

Current State of Pediatric Cardio-Oncology: A Review

The landscape of pediatric oncology has dramatically changed over the course of the past several decades with five-year survival rates surpassing 80%. Anthracycline therapy has been the cornerstone of many chemotherapy regimens for pediatric patients since its introduction in the 1960s, and recent improved survival has been in large part due to advancements in chemotherapy, refinement of supportive care treatments, and development of novel therapeutics such as small molecule inhibitors, chimeric antigen receptor T-cell therapy, and immune checkpoint inhibitors. Unfortunately, many cancer-targeted therapies can lead to acute and chronic cardiovascular pathologies. The range of cardiotoxicity can vary but includes symptomatic or asymptotic heart failure, arrhythmias, coronary artery disease, valvar disease, pericardial disease, hypertension, and peripheral vascular disease. There is lack of data guiding primary prevention and treatment strategies in the pediatric population, which leads to substantial practice variability. Several important future research directions have been identified, including as they relate to cardiac disease, prevention strategies, management of cardiovascular risk factors, risk prediction, early detection, and the role of genetic susceptibility in development of cardiotoxicity. Continued collaborative research will be key in advancing the field. The ideal model for pediatric cardio-oncology is a proactive partnership between pediatric cardiologists and oncologists in order to better understand, treat, and ideally prevent cardiac disease in pediatric oncology patients.

Mechanisms of Immunosuppressive Tumor Evasion: Focus on Acute Lymphoblastic Leukemia

Acute lymphoblastic leukemia (ALL) is a malignancy with high heterogeneity in its biological features and treatments. Although the overall survival (OS) of patients with ALL has recently improved considerably, owing to the application of conventional chemo-therapeutic agents, approximately 20% of the pediatric cases and 40-50% of the adult patients relapse during and after the treatment period. The potential mechanisms that cause relapse involve clonal evolution, innate and acquired chemoresistance, and the ability of ALL cells to escape the immune-suppressive tumor response. Currently, immunotherapy in combination with conventional treatment is used to enhance the immune response against tumor cells, thereby significantly improving the OS in patients with ALL. Therefore, understanding the mechanisms of immune evasion by leukemia cells could be useful for developing novel therapeutic strategies.