High and low, but not intermediate,PRAMEexpression levels are poor prognostic markers in myelodysplastic syndrome at disease presentation

Increasing Role of Targeted Immunotherapies in the Treatment of AML

Acute myeloid leukemia (AML) is the most common acute leukemia in adults. The standard of care in medically and physically fit patients is intensive induction therapy. The majority of these intensively treated patients achieve a complete remission. However, a high number of these patients will experience relapse. In patients older than 60 years, the results are even worse. Therefore, new therapeutic approaches are desperately needed. One promising approach in high-risk leukemia to prevent relapse is the induction of the immune system simultaneously or after reduction of the initial tumor burden. Different immunotherapeutic approaches such as allogenic stem cell transplantation or donor lymphocyte infusions are already standard therapies, but other options for AML treatment are in the pipeline. Moreover, the therapeutic landscape in AML is rapidly changing, and in the last years, a number of immunogenic targets structures eligible for specific therapy, risk assessment or evaluation of disease course were determined. For example, leukemia-associated antigens (LAA) showed to be critical as biomarkers of disease state and survival, as well as markers of minimal residual disease (MRD). Yet many mechanisms and properties are still insufficiently understood, which also represents a great potential for this form of therapy. Therefore, targeted therapy as immunotherapy could turn into an efficient tool to clear residual disease, improve the outcome of AML patients and reduce the relapse risk. In this review, established but also emerging immunotherapeutic approaches for AML patients will be discussed.

The Prognostic Value of Early Detection of Minimal Residual Disease as Defined by Flow Cytometry and Gene Mutation Clearance for Myelodysplastic Syndrome Patients After Myeloablative Allogeneic Hematopoietic Stem-Cell Transplantation

High relapse incidence remains a major problem for myelodysplastic syndrome (MDS) patients who have received an allogeneic hematopoietic stem-cell transplantation (allo-HSCT). We retrospectively analyzed the correlations between clinical outcomes and minimal residual disease (MRD) by using mutations (MUT) and flow cytometry (FCM) analysis of 115 MDS patients with allo-HSCT. We divided 115 MDS patients into four groups based on molecular genetics and FCM MRD results at day 30 post-HSCT. There were significant differences in the 2-year progression-free survival (PFS) between the FCM^high MUT^pos and FCM^low MUT^neg groups (20% vs 79%, P < 0.001). In addition, by univariate analysis, we found that an IPSS-R score ≥4 pre-HSCT (HR, 5.061; P=0.007), DNMT3A mutations (HR, 2.291; P=0.052), TP53 mutations (HR, 3.946; P=0.011), and poor and very poor revised International Prognostic Scoring System (IPSS-R) cytogenetic risk (HR, 4.906; P < 0.001) were poor risk factors for PFS. In multivariate analysis, we found that an IPSS-R score ≥ 4 pre-HSCT (HR, 4.488; P=0.015), DNMT3A mutations (HR, 2.385; P=0.049), positive FCM MRD combined with persistence gene mutations at day 30 (HR, 5.198; P=0.013) were independent risk factors for disease progression. In conclusion, our data indicated that monitoring MRD by FCM combined with gene mutation clearance at day 30 could help in the prediction of disease progression for MDS patients after transplantation.

High PRAME expression is associated with poor survival and early disease progression in myelodysplastic syndromes with a low bone marrow blast percentage

We investigated the clinical implications of preferentially expressed antigen in melanoma (PRAME) expression in bone marrow cells of 116 patients with myelodysplastic syndromes (MDS). Quantitative RT-PCR was carried out to examine the PRAME expression level. High PRAME expression was observed in MDS patients classified into higher revised International Prognostic Scoring System (IPSS-R) risk categories (Very high and High) with a high bone marrow blast percentage (5% or higher). Kaplan-Meier analysis demonstrated that high PRAME expression is significantly associated with a poorer overall survival (OS) in MDS patients with a low bone marrow blast percentage (less than 5%) (log-rank test p = .0014) and those classified into lower IPSS-R risk categories (Very Low, Low, and Intermediate) (log-rank test, p = .0035). In contrast, there was no significant association between PRAME expression and OS in MDS patients with a high bone marrow blast percentage or those classified into higher IPSS-R risk categories. In addition, high PRAME expression was associated with early disease progression in MDS patients with a low bone marrow blast percentage. This study suggested PRAME expression to be a prognostic factor in MDS.

Identification of Genes Whose Expression Overlaps Age Boundaries and Correlates with Risk Groups in Paediatric and Adult Acute Myeloid Leukaemia

Simple Summary

To better understand whether acute myeloid leukaemia differs between children and adults, we have analysed the expression of genes in samples from both patient groups. Using previously published data, we compared gene expression between patient risk subgroups. We examined patients who had a poor chance of survival, based on clinical assessments, and those with a good chance of survival, to see whether there was any difference in the genes expressed in their leukaemic cells. Then we compared the genes on these lists between adults and children with acute myeloid leukaemia. We believe that patients with good or poor survival chances express genes that provide insights into how leukaemic cells behave. We hope that this work will provide new information about the mechanisms that underlie acute myeloid leukaemia and answer questions on the ways this form of leukaemia is similar in adults and children, which will then tell us whether the same treatments could be used for both age groups of patients.

Abstract

Few studies have compared gene expression in paediatric and adult acute myeloid leukaemia (AML). In this study, we have analysed mRNA-sequencing data from two publicly accessible databases: (1) National Cancer Institute’s Therapeutically Applicable Research to Generate Effective Treatments (NCI-TARGET), examining paediatric patients, and (2) The Cancer Genome Atlas (TCGA), examining adult patients with AML. With a particular focus on 144 known tumour antigens, we identified STEAP1, SAGE1, MORC4, SLC34A2 and CEACAM3 as significantly different in their expression between standard and low risk paediatric AML patient subgroups, as well as between poor and good, and intermediate and good risk adult AML patient subgroups. We found significant differences in event-free survival (EFS) in paediatric AML patients, when comparing standard and low risk subgroups, and quartile expression levels of BIRC5, MAGEF1, MELTF, STEAP1 and VGLL4. We found significant differences in EFS in adult AML patients when comparing intermediate and good, and poor and good risk adult AML patient subgroups and quartile expression levels of MORC4 and SAGE1, respectively. When examining Kyoto Encyclopedia of Genes and Genomes (KEGG) (2016) pathway data, we found that genes altered in AML were involved in key processes such as the evasion of apoptosis (BIRC5, WNT1) or the control of cell proliferation (SSX2IP, AML1-ETO). For the first time we have compared gene expression in paediatric AML patients with that of adult AML patients. This study provides unique insights into the differences and similarities in the gene expression that underlies AML, the genes that are significantly differently expressed between risk subgroups, and provides new insights into the molecular pathways involved in AML pathogenesis.

Serum profiling identifies ibrutinib as a treatment option for young adults with B-cell acute lymphoblastic leukaemia

Acute lymphoblastic leukaemia (ALL) is a haematological malignancy that is characterized by the uncontrolled proliferation of immature lymphocytes. 80% of cases occur in children where ALL is well understood and treated. However it has a devastating affects on adults, where multi-agent chemotherapy is the standard of care with allogeneic stem cell transplantation for those who are eligible. New treatments are required to extend remission and prevent relapse to improve patient survival rates. We used serum profiling to compare samples from presentation adult B-ALL patients with age- and sex-matched healthy volunteer (HV) sera and identified 69 differentially recognised antigens (P ≤ 0·02). BMX, DCTPP1 and VGLL4 showed no differences in transcription between patients and healthy donors but were each found to be present at higher levels in B-ALL patient samples than HVs by ICC. BMX plays a crucial role in the Bruton's Tyrosine Kinase (BTK) pathway which is bound by the BTK inhibitor, ibrutinib, suggesting adult B-ALL would also be a worthy target patient group for future clinical trials. We have shown the utility of proto-array analysis of B-ALL patient sera, predominantly from young adults, to help characterise the B-ALL immunome and identified a new target patient population for existing small molecule therapy.

The role of the cancer testis antigen PRAME in tumorigenesis and immunotherapy in human cancer

Preferentially expressed antigen in melanoma (PRAME), which belongs to the cancer/testis antigen (CTA) gene family, plays a pivotal role in multiple cellular processes and immunotherapy response in human cancers. PRAME is highly expressed in different types of cancers and is involved in cell proliferation, apoptosis, differentiation and metastasis as well as the outcomes of patients with cancer. In this review article, we discuss the potential roles and physiological functions of PRAME in various types of cancers. Moreover, this review highlights immunotherapeutic strategies that target PRAME in human malignancies. Therefore, the modulation of PRAME might be useful for the treatment of patients with cancer.

Antigenic Targets for the Immunotherapy of Acute Myeloid Leukaemia

One of the most promising approaches to preventing relapse is the stimulation of the body’s own immune system to kill residual cancer cells after conventional therapy has destroyed the bulk of the tumour. In acute myeloid leukaemia (AML), the high frequency with which patients achieve first remission, and the diffuse nature of the disease throughout the periphery, makes immunotherapy particularly appealing following induction and consolidation therapy, using chemotherapy, and where possible stem cell transplantation. Immunotherapy could be used to remove residual disease, including leukaemic stem cells from the farthest recesses of the body, reducing, if not eliminating, the prospect of relapse. The identification of novel antigens that exist at disease presentation and can act as targets for immunotherapy have also proved useful in helping us to gain a better understand of the biology that belies AML. It appears that there is an additional function of leukaemia associated antigens as biomarkers of disease state and survival. Here, we discuss these findings.

Methylation pattern of preferentially expressed antigen of melanoma in acute myeloid leukemia and myelodysplastic syndromes

Preferentially expressed antigen of melanoma (PRAME), a tumor-associated antigen, is overexpressed in a variety of hematologic malignancies with a great variation in expression. The majority of patients with acute myeloid leukemia (AML) 1-eight-twenty one (ETO)⁺ AML and a certain number of myelodysplastic syndromes (MDS) have an abnormally high increase in PRAME expression level. The landscape of PRAME methylation requires evaluation in order to determine the most relevant sites and the exact association of its methylation with expression level and type of disease. In the present study, bone marrow samples collected from 8 AML1-ETO⁺ AML, 4 MDS, 3 AML1-ETO^- AML and 2 normal volunteers underwent bisulfate sequencing to analyze the methylation status of all four 5'-C-phosphate-G-3' (CpG) regions within the entire PRAME gene. The median PRAME transcript level of 15 patients was 204.5% (range, 0.02-710.3%). PRAME transcript levels were inversely associated with the degree of methylation of the -389 to -146 CpG sites (r=-0.69; P=0.002) in the 3' part of the promoter region and the +132 to +363 CpG sites (r=-0.69; P=0.006) in the exon 1b region. However, not every sample strictly followed this correlation: Certain samples with high degrees of methylation demonstrated abnormally high expression levels, and vice versa. The methylation ratios of CpG sites in exon 1a were low for all samples (range, 0.0-13.8%), and those in exon 2 were similar in 16 samples (range, 72.4-93.4%), with the exception of one patient with high expression (425.2%) and significantly low degree of methylation in the PRAME gene (22.2%). MDS patients revealed similar methylation ratios in the 3' section of the promoter region, but tended to have lower methylation ratios in the exon 1b region (P=0.62 and P=0.09, respectively) compared with those observed in AML1-ETO⁺ patients with AML and similar degree of PRAME overexpression. Therefore, the hypomethylation of CpG sites in the 3' part of the promoter region and in exon 1b was typically found with PRAME overexpression in AML and MDS. Methylation of other CpG islands, epigenetic and genetic mechanisms, and type of disease may also be involved.

Minimal residual disease monitoring and preemptive immunotherapy in myelodysplastic syndrome after allogeneic hematopoietic stem cell transplantation

This study investigated the efficacy of minimal residual disease (MRD) monitoring and MRD-directed preemptive immunotherapy in high-risk myelodysplastic syndrome (MDS) patients who received allogeneic hematopoietic stem cell transplantation (HSCT). MRD assessment consisted of Wilms' tumor gene 1 (WT1) detection with PCR and leukemia-associated immunophenotypic pattern examination with multiparameter flow cytometry (FCM). Post-HSCT, 31 patients were positive for WT1, and 8, for FCM; positivity for WT1 (18.6 vs. 6.1 %, P = 0.040) or FCM (62.5 vs. 3.6 %, P < 0.001) indicated a higher 2-year relapse rate. Twenty-one patients met our combined criteria for MRD, and the presence of MRD was associated with a higher 2-year relapse rate (27.3 vs. 4.5 %, P = 0.003). Preferentially expressed antigen of melanoma (PRAME) expression alone was not an appropriate MRD marker; however, it suggested that the MRD-positive patients may fail to respond to preemptive immunotherapy. In patients positive for both PRAME and MRD, the relapse rate was 60 % despite preemptive immunotherapy. Multivariate analysis confirmed the association between the increased relapse rate and positivity for both PRAME and MRD (hazard ratio = 42.8, P = 0.001). MRD monitoring predicted relapse in high-risk MDS post-HSCT patients, and PRAME- and MRD-positive patients did not benefit from preemptive immunotherapy.

Variant of BCL3 gene is strongly associated with five-year survival of non-small-cell lung cancer patients

OBJECTIVES

BCL3, a known atypical IκB family member, has been documented to be upregulated in hematological malignancies and in some solid tumors, functioning as a crucial player in tumor development. Recently, rs8100239, a tag-Single Nucleotide Polymorphism (SNP) in BCL3 (T>A) has been identified, but there are no data regarding its involvement in non-small-cell lung cancer (NSCLC) initiation and progression.

MATERIALS AND METHODS

To study the possible association of BCL3 with NSCLC, 268 patients and 279 healthy controls were genotyped for rs8100239. Moreover, BCL3 protein expression was also investigated in 112 NSCLC cases through an immunohistochemical analysis.

RESULTS

NSCLC patients with AA genotype displayed significantly worse prognosis compared to T allele carriers (P<0.001), who had less frequent intermediate nuclear BCL3 expression (P=0.042). In addition, overexpression of BCL3 was detected in tumor specimens, compared to normal tissue (P<0.001). Furthermore, BCL3 protein levels were associated with five-year survival (P=0.039), maximum diameter of lesion (P=0.012), grade (P=0.002) and relapse frequency (P=0.041).

CONCLUSIONS

The present study is the first to show a relationship between the genetic variation rs8100239 of BCL3 and cancer patients' survival. It also represents the first quantitative evaluation of BCL3 expression in NSCLC. Our findings indicate that rs8100239 may be considered as a novel prognostic indicator, demonstrating also the overexpression of BCL3 protein in NSCLC and implicating this pivotal molecule in the pathogenesis of NSCLC.