High incidence of Epstein Barr virus infection in childhood acute lymphocytic leukemia: a preliminary study

Acute Lymphoblastic Leukemia Immunotherapy Treatment: Now, Next, and Beyond

Acute lymphoblastic leukemia (ALL) is a blood cancer that primarily affects children but also adults. It is due to the malignant proliferation of lymphoid precursor cells that invade the bone marrow and can spread to extramedullary sites. ALL is divided into B cell (85%) and T cell lineages (10 to 15%); rare cases are associated with the natural killer (NK) cell lineage (<1%). To date, the survival rate in children with ALL is excellent while in adults continues to be poor. Despite the therapeutic progress, there are subsets of patients that still have high relapse rates after chemotherapy or hematopoietic stem cell transplantation (HSCT) and an unsatisfactory cure rate. Hence, the identification of more effective and safer therapy choices represents a primary issue. In this review, we will discuss novel therapeutic options including bispecific antibodies, antibody-drug conjugates, chimeric antigen receptor (CAR)-based therapies, and other promising treatments for both pediatric and adult patients.

Comparative Genomic Hybridization and Transcriptome Sequencing Reveal Genes with Gain in Acute Lymphoblastic Leukemia: JUP Expression Emerges as a Survival-Related Gene

Acute lymphoblastic leukemia (ALL) in children or adults is characterized by structural and numeric aberrations in chromosomes; these anomalies strongly correlate with prognosis and clinical outcome. Therefore, this work aimed to identify the genes present in chromosomal gain regions found more frequently in patients with acute lymphoblastic leukemia (ALL) and ALL-derived cell lines using comparative genomic hybridization (CGH). In addition, validation of the genes found in these regions was performed utilizing RNAseq from JURKAT, CEM, and SUP-B15 cell lines, as well as expression microarrays derived from a MILE study. Chromosomes with common gain zones that were maintained in six or more samples were 14, 17, and 22, in which a total of 22 genes were identified. From them, NT5C3B, CNP, ACLY, and GNB1L maintained overexpression at the mRNA level in the cell lines and in patients with ALL. It is noteworthy that SALL2 showed very high expression in T-ALL, while JUP was highly expressed in B-ALL lineages. Interestingly, the latter correlated with worse survival in patients. This provided evidence that the measurement of these genes has high potential for clinical utility; however, their expressions should first be evaluated with a sensitive test in a more significant number of patients.

Clinical profile and outcomes of Non-Hodgkin's lymphoma in children: A report from a tertiary care hospital from India

Background: Non-Hodgkin's lymphoma (NHL) is an aggressive malignancy. Its outcome has improved over the past decades. Although it accounts for 8%–10% of all childhood cancers, very less information about its clinical presentation and outcomes is available from India. Our objective was to study the clinical presentation and outcomes in children (<15 years) with NHL at our center. Methodology: We retrospectively analyzed 26 children diagnosed with NHL at our center from August 2008 to June 2014 and followed them up to May 2017. Results: The median age at the time of diagnosis was 7.7 years (2.5–13 years). Abdominal distension and an abdominal lump were the most common presenting features occurring in 75%, followed by fever (73.8%) and weight loss (46.2%). Most patients had advanced-stage (Stage III/IV, 92.3%) disease at presentation. The primary presentation was extranodal in 57.7%, nodal in 26.9%, and combined in 15.4%. Burkitt's lymphoma (BL) was the most common subtype (46.2%), followed by T-lymphoblastic lymphoma, diffuse large B-cell lymphoma, and anaplastic large-cell lymphoma. Three patients did not take treatment. The median follow-up of patients was 48 months (36–99 months). Nineteen patients achieved remission and four had progressive disease. Significantly better event-free survival (EFS) was found with younger age and lower stage of presentation. The EFS did not significantly differ with sex, group of disease, lactate dehydrogenase levels, and presenting features. Conclusions: Our cohort of patients with NHL showed characteristics similar to those reported from other developing countries. NHL occurred at a younger age, with a higher incidence of BL. The outcome for patients aged >10 years was poor. The outcome of NHL was comparable to that of other centers in the world.

Sequence Variations of Epstein-Barr Virus-Encoded Small Noncoding RNA and Latent Membrane Protein 1 in Hematologic Tumors in Northern China

OBJECTIVE

To investigate the relationship between hematologic tumors and Epstein-Barr virus (EBV)-encoded small noncoding RNA (EBER) variations as well as latent membrane protein 1 (LMP1) variations.

METHODS

Patients with leukemia and myelodysplastic syndrome (MDS) were selected as subjects. Genotypes 1/2 and genotypes F/f were analyzed using the nested PCR technology, while EBER and LMP1 subtypes were analyzed by the nested PCR and DNA sequencing.

RESULTS

Type 1 was more dominant than type 2, found in 59 out of 82 (72%) leukemia and in 31 out of 35 (88.6%) MDS, while type F was more prevalent than type f in leukemia (83/85, 97.6%) and MDS (29/31, 93.5%) samples. The distribution of EBV genotypes 1/2 was not significantly different among leukemia, MDS, and healthy donor groups, neither was that of EBV genotypes F/f. EB-6m prototype was the dominant subtype of EBER in leukemia and MDS (73.2% [30/41] and 83.3% [10/12], respectively). The frequency of EB-6m was lower than that of healthy people (96.7%, 89/92), and the difference was significant (p < 0.05). China 1 subtype was the dominant subtype of LMP1 in leukemia and MDS (70% [28/40] and 90% [9/10], respectively), and there was no significant difference in the distribution of LMP1 subtypes among the 3 groups (p > 0.05).

CONCLUSION

The distribution of EBV 1/2, F/f, EBER, and LMP1 subtypes in leukemia and MDS was similar to that in the background population in Northern China, which means that these subtypes may be rather region-restricted but not associated with leukemia and MDS pathogenesis.

Acute lymphoblastic leukemia: a comprehensive review and 2017 update

Acute lymphoblastic leukemia (ALL) is the second most common acute leukemia in adults, with an incidence of over 6500 cases per year in the United States alone. The hallmark of ALL is chromosomal abnormalities and genetic alterations involved in differentiation and proliferation of lymphoid precursor cells. In adults, 75% of cases develop from precursors of the B-cell lineage, with the remainder of cases consisting of malignant T-cell precursors. Traditionally, risk stratification has been based on clinical factors such age, white blood cell count and response to chemotherapy; however, the identification of recurrent genetic alterations has helped refine individual prognosis and guide management. Despite advances in management, the backbone of therapy remains multi-agent chemotherapy with vincristine, corticosteroids and an anthracycline with allogeneic stem cell transplantation for eligible candidates. Elderly patients are often unable to tolerate such regimens and carry a particularly poor prognosis. Here, we review the major recent advances in the treatment of ALL.

Epstein-Barr virus and cytomegalovirus infections and their clinical relevance in Egyptian leukemic pediatric patients

Background

Epstein-Barr virus (EBV) and human cytomegalovirus (CMV) infections are environmental risk factors affecting the outcome of cancer due to an impairment in the cell-mediated immunity. Therefore, this study aimed to detect the frequency of EBV and CMV DNA and their association with clinical characteristics and outcome of pediatric leukemic patients.

Methods

Samples of 50 immunocompromised pediatric leukemic patients and 30 apparently healthy children were subjected to the amplification of EBV DNA by one version of PCR targeting the Bam H1 W region of the genomic region of EBV, and the amplification of CMV DNA by targeting the CMV UL97 genomic region by a second round PCR. All investigations were performed on WBCs and sera. Results were correlated with the clinical and laboratory characteristics of the disease, and with overall survival.

Results

EBV and CMV DNA were detected in 20 and 54% of leukemic patients, respectively. Nine out of ten patients with EBV DNA (90%) were positive for CMV DNA in their sera. The presence of EBV DNA or CMV DNA was associated with neutropenia and a low total leukocyte count (TLC) (p = 0.02, 0.03, respectively). The presence of severe CMV disease, longer duration of febrile neutropenia, neutropenia, lymphopenia, thrombocytopenia and the presence of EBV DNA in patients’ sera were significantly associated with worse overall survival.

Conclusion

The detection of CMV disease and EBV DNA is relatively common in leukemic children and is significantly associated with a decline in the overall survival.

Epstein-Barr virus and regulatory T cells in Egyptian paediatric patients with acute B lymphoblastic leukaemia

OBJECTIVE

Acute B lymphoblastic leukaemia (B-ALL) is the most common type of childhood malignancy worldwide but little is known of its origin. Recently, many studies showed both a high incidence of Epstein-Barr virus (EBV) infection and high levels of CD4⁺CD25⁺Foxp3⁺(Treg cells) in children with B-ALL. In our study, we investigated the possible relationship between EBV infection and the onset of B-ALL, and its relation to expression of CD4⁺, CD25^high+Foxp3+ T regulatory cells.

SUBJECT AND METHODS

We analysed expression and mean fluorescence intensity (MFI) of Treg cells in peripheral blood of 45 children with B-ALL and in 40 apparently healthy children as a control, using flow cytometry. Serum anti-EBV viral capsid antigen (VCA) IgG, anti-EBV nuclear antigen (EBNA) IgG (for latent infection) and anti-EBV VCA IgM (for acute infection) were investigated using ELISA.

RESULTS

Analysis of the Treg cells population in patients and controls revealed that expression of CD4⁺ CD25^high+ T lymphocytes was higher in patients than in controls (mean±SD 15.7±4.1 and 10.61±2.6 in patients and controls, respectively, and MFI of Foxp3 was 30.1±7.1 and 16.7±3.7 in patients and controls, respectively (p<0.001)). There was a high incidence of latent EBV infection in patients (31%) compared with controls (10%) while the incidence of acute infection was 12% in patients and 0% in the control group. To study the role of latent EBV infection in the pathogenesis of acute B-ALL, OR was calculated (OR=4.06, coefficient index 1.2-13.6).

CONCLUSIONS

These findings suggest a possible role for Treg cells and EBV in the pathogenesis of B-ALL. Further studies are needed on the possible mechanisms of tumour genesis related to Treg cells and EBV in children with B-ALL.

DNA methylation as a potential mediator of environmental risks in the development of childhood acute lymphoblastic leukemia

5-year survival rate for childhood acute lymphoblastic leukemia (ALL) has risen to approximately 90%, yet the causal disease pathway is still poorly understood. Evidence suggests multiple 'hits' are required for disease progression; an initial genetic abnormality followed by additional secondary 'hits'. It is plausible that environmental influences may trigger these secondary hits, and with the peak incidence of diagnosis between 2 and 5 years of age, early life exposures are likely to be key. DNA methylation can be modified by many environmental exposures and is dramatically altered in cancers, including childhood ALL. Here we explore the potential that DNA methylation may be involved in the causal pathway toward disease by acting as a mediator between established environmental factors and childhood ALL development.

Infection and childhood leukemia: review of evidence

OBJECTIVE

To analyze studies that evaluated the role of infections as well as indirect measures of exposure to infection in the risk of childhood leukemia, particularly acute lymphoblastic leukemia.

METHODS

A search in Medline, Lilacs, and SciELO scientific publication databases initially using the descriptors "childhood leukemia" and "infection" and later searching for the words "childhood leukemia" and "maternal infection or disease" or "breastfeeding" or "daycare attendance" or "vaccination" resulted in 62 publications that met the following inclusion criteria: subject aged ≤ 15 years; specific analysis of cases diagnosed with acute lymphoblastic leukemia or total leukemia; exposure assessment of mothers' or infants' to infections (or proxy of infection), and risk of leukemia.

RESULTS

Overall, 23 studies that assessed infections in children support the hypothesis that occurrence of infection during early childhood reduces the risk of leukemia, but there are disagreements within and between studies. The evaluation of exposure to infection by indirect measures showed evidence of reduced risk of leukemia associated mainly with daycare attendance. More than 50.0% of the 16 studies that assessed maternal exposure to infection observed increased risk of leukemia associated with episodes of influenza, pneumonia, chickenpox, herpes zoster, lower genital tract infection, skin disease, sexually transmitted diseases, Epstein-Barr virus, and Helicobacter pylori.

CONCLUSIONS

Although no specific infectious agent has been identified, scientific evidence suggests that exposure to infections has some effect on childhood leukemia etiology.

Childhood cancers: what is a possible role of infectious agents?

The etiology of childhood cancers has been studied for more than 40 years. However, most if not all cancers occurring in children are attributed to unknown causes. This review is focused on the role of infections in cancer development and progression in children. The main infectious agents include human herpesviruses, polyoma viruses, and human papilloma viruses. It is known that infections can lead to carcinogenesis through various mechanisms, and most likely act in addition to genetic and environmental factors. Given the importance of the infectious etiology of childhood cancers, clinical implications and possible prevention strategies are discussed.

Incidence of Epstein-Barr virus in pediatric leukemia in the Sudan

BACKGROUND

Results of several studies have suggested a probable etiologic association between Epstein-Barr virus (EBV) and leukemias; therefore, the aim of this study was to investigate the association of EBV in childhood leukemia.

METHODS

A direct isothermal amplification method was developed for detection of the latent membrane protein 1 (LMP1) of EBV in the peripheral blood of 80 patients with leukemia (54 had lymphoid leukemia and 26 had myeloid leukemia) and of 20 hematologically healthy control subjects.

RESULTS

EBV LMP1 gene transcripts were found in 29 (36.3%) of the 80 patients with leukemia but in none of the healthy controls (P < .0001). Of the 29 EBV(+) cases, 23 (79.3%), 5 (17.3%), and 1 (3.4%) were acute lymphoblastic leukemia, acute myeloid leukemia, and chronic myeloid leukemia, respectively.

CONCLUSION

EBV LMP1 gene transcriptional activity was observed in a significant proportion of patients with acute lymphoblastic leukemia. EBV infection in patients with lymphoid leukemia may be a factor involved in the high incidence of pediatric leukemia in the Sudan.

Non-Hodgkin lymphoma in childhood and adolescence: frequency and distribution of immunomorphological types from a tertiary care center in South India

BACKGROUND

There is a dearth of published literature on the frequency and distribution of pediatric and adolescent non-Hodgkin lymphoma (NHL) in India according to the 2001 WHO classification. The aim of this study was to record the distribution of the different subtypes, analyze the major subtypes, and compare it with the published data from other countries. A review of pediatric NHL statistics from population-based cancer registries was included in this study.

METHODS

The study was conducted using information retrieved from the files of our institution. A total of 467 patients with lymphoma (excluding mycosis fungoides) were recorded in the under 20 years group over a period of 6 years, of which 252 patients suffered from NHL. The demographic characteristics, frequency and distribution of different subtypes were noted and compared with published reports from other parts of the world.

RESULTS

T-lymphoblastic lymphoma/leukemia constituted the majority (32.1%) of all NHLs in children and adolescents in our study. The other major subgroups were Burkitt's lymphoma, anaplastic large cell lymphoma, and diffuse large B cell lymphoma. Burkitt's lymphoma in this study had clinical presentations similar to those seen in western countries.

CONCLUSIONS

The distribution of different subtypes of lymphoma in pediatric and adolescent NHL in India differs considerably from that in western countries and other eastern countries.