Dysregulation of immune cell and cytokine signaling correlates with clinical outcomes in myelodysplastic syndrome (MDS)

OBJECTIVES

Myelodysplastic syndromes (MDS) are characterized by ineffective hematopoiesis. Although hypomethylating agents (HMA) have improved survival in higher-risk MDS, most patients eventually succumb to progressive disease. Utilizing samples collected prospectively from three MDS clinical trials, we analyzed genetic and immunological biomarkers and correlated them with clinical outcomes.

METHODS

154 samples were analyzed from 133 de novo MDS patients for T-cell and myeloid cell immunophenotyping and gene expression analysis. Treatments were with HMA or immunomodulatory drug (IMiD) alone or in combination.

RESULTS

We observed differences in immune cell subsets between lower and higher risk IPSS groups with NKT cells, MDSCs, intermediate-proinflammatory and non-classical monocytes being higher in the latter group while naïve CD4+ T-cells were reduced. Intermediate-proinflammatory monocytes were increased in non-responders and those failing to achieve at least a hematological improvement. Pro-inflammatory NKT cells were increased at diagnosis for patients failing to derive clinical benefit after 12 months of treatment. Gene expression analysis of paired bone marrow (BM) colony-forming units (CFUs) from diagnosis and 4 cycles post-treatment confirmed that genes involved in cytokine signaling were downregulated in C4 normal colonies.

CONCLUSIONS

These findings support the central roles of dysregulation in innate immunity and inflammatory signaling in the pathogenesis of MDS which correlated with clinical outcomes post-treatment.

Hemoglobin is a key determinant of quality of life before and during azacitidine-based therapy for myelodysplasia and low blast count acute myeloid leukemia

Myelodysplastic syndromes (MDS) have a major impact on quality of life (QoL). We performed a post hoc analysis of two multicenter trials of azacitidine-based disease-modifying therapy for patients with MDS and low blast count acute myeloid leukemia (AML), to identify factors associated with QoL. 231 patients were included (median age 70 years). At baseline, higher initial hemoglobin, but not neutrophil or platelet count, was associated with better global QoL and physical function (p < 0.001 and p = 0.001, respectively). During therapy, increase in hemoglobin was associated with improvement in QoL and physical function (p = 0.005 and p < 0.001, respectively). Lower initial hemoglobin was associated with higher dyspnea and fatigue scores (p < 0.001 and p = 0.001, respectively), and hemoglobin response was associated with improvement in dyspnea and fatigue (p < 0.001 for each). In patients with MDS and low blast count AML, hemoglobin level was strongly correlated with global QoL, physical functioning, dyspnea and fatigue, both before and during azacitidine-based therapy.

Azacitidine with or without lenalidomide in higher risk myelodysplastic syndrome & low blast acute myeloid leukemia

Standard treatment for higher risk myelodysplastic syndromes, chronic myelomonocytic leukemia and low blast acute myeloid leukemia is azacitidine. In single arm studies, adding lenalidomide had been suggested to improve outcomes. The ALLG MDS4 phase II trial randomized such patients to standard azacitidine or combination azacitidine (75mg/m²/d days 1 to 5) with lenalidomide (10mg days 1–21 of 28-day cycle from cycle 3) to assess clinical benefit (alive without progressive disease) at 12 months. A total of 160 patients were enrolled; median age 70.7 years (range 42.5-87.2), 31.3% female with 14% chronic myelomonocytic leukemia, 12% acute myeloid leukemia and 74% myelodysplastic syndromes. Adverse events were similar in both arms. There was excellent delivery of protocol therapy (median azacitidine cycles 11 both arms) with few dose reductions, delays or early cessations. At median follow up 33.1 months (range 0.7-59.5), the rate of clinical benefit at 12 months was 65% azacitidine arm and 54% lenalidomide+azacitidine arm (P=0.2). There was no difference in clinical benefit between each arm according to WHO diagnostic subgroup or IPSS-R. Overall response rate was 57% in azacitidine arm and 69% in lenalidomide+azacitidine (P=0.14). There was no difference in progression- free or overall survival between the arms (each P>0.12). Although the combination of lenalidomide and azacitidine was tolerable, there was no improvement in clinical benefit, response rates or overall survival in higher risk myelodysplastic syndrome, chronic myelomonocytic leukemia or low blast acute myeloid leukemia patients compared to treatment with azacitidine alone. This trial was registered at www.anzc-tr.org.au as ACTRN12610000271000.

Abstract 1548: Genetic biomarkers predict clinical response and survival in myelodysplasia

Background: Hypomethylating agents (HMA) used in higher-risk myelodysplastic syndromes (MDS) improve survival but HMA-failure has a poor prognosis. Abnormal bone marrow (BM) colony-forming units (CFUs) persist in treated MDS patients despite achievement of complete remission, suggesting persistent abnormal stem cell function. We aim to identify genetic biomarkers following treatment with Azacitidine ± Thalidomide or Lenalidomide that predict clinical outcomes in MDS.

Methods: BM cells from patients enrolled in ALLG MDS3 and MDS4 clinical trials at baseline and after 4 cycles of treatment (C4) were grown in Methocult for 14 days. CFUs were pooled at baseline; C4 macroscopically normal and abnormal colonies were harvested separately. mRNA expression was quantified using the Nanostring nCounter PanCancer Pathways panel. Clinical outcomes analysed were: (1) clinical benefit at 12 months (haematological improvement or better as per IWG criteria) (2) best response achieved. Genes expressed above background level in ≥25% of samples were included for statistical analyses, resulting in 516 genes across 56 samples from 23 different patients. R limma package was used for differential expression analysis. Patients were weighted using limma's voomWithQualityWeights function. Moderated t-tests with empirical Bayes were done to identify differentially expressed genes. For testing between colonies, a log-fold-change cut-off of 0.5 was used with limma's treat function. P-values were adjusted for multiple hypothesis testing.

Results: 98 genes exhibited significantly different expression (p &lt;0.05) when comparing C4 normal to baseline colonies and 118 genes were differentially expressed between C4 normal to C4 abnormal colonies. Key results are summarised: (1) Within C4 normal colonies - RFC3 (p=0.04) and LTBP1 (p=0.04) were upregulated in patients with clinical benefit at 12 months (2) Within C4 abnormal colonies - FN1 (p=0.03) was upregulated in those failing to achieve at least a partial response (PR) (3) Comparing C4 normal colonies to baseline: a. The top 5 differentially expressed genes: MAPK12, PLAU, FGFR1, IL10 and FLNA (p&lt;0.001) were downregulated in the C4 normal group; b. In addition, for patients with clinical benefit, MYD88 and PIK3R5 were downregulated (p&lt;0.001) while; c. In patients who achieved at least a PR as best response, NFKB1, SYK and TGFBR2 were downregulated (p&lt;0.001). d. Gene ontology analysis revealed upregulated genes involved in plasma membrane and cytokine production were over-represented at baseline while; e. KEGG pathway analysis showed upregulated genes involved in the cytokine receptor, Notch and NF-kB signalling pathways.

Conclusion: We identified changes in gene expression following treatment in MDS that predict outcomes in response and clinical benefit. These genetic biomarkers require further validation and could define early markers of resistance for investigation of novel therapies.

Citation Format: Lynette Chee, David Ritchie, Jessica Chung, Daniel Park, Mandy Ludford-Menting, Jane Ripley, Melita Kenealy, Rachel Koldej. Genetic biomarkers predict clinical response and survival in myelodysplasia [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1548.

Results of a phase II study of thalidomide and azacitidine in patients with clinically advanced myelodysplastic syndromes (MDS), chronic myelomonocytic leukemia (CMML) and low blast count acute myeloid leukemia (AML)

Single agent azacitidine or immunomodulatory drugs are effective in myelodysplastic syndrome (MDS), with differing target mechanisms and toxicities. Objectives of this ALLG MDS3 study in clinically advanced MDS, AMML and low blast AML were to establish safety, response and quality of life of azacitidine and thalidomide. Patients received azacitidine (75mg/m²/d sc 7days every 28 days), and oral thalidomide up to 100mg/d for maximum 12months. Eighty patients registered; median age 68 years (range 42-82), 49% IPSS int2-high. With 36.5 months follow up, patients received median 9 cycles azacitidine, 6.1mths thalidomide. Nonhematologic toxicity grade 3+ in 85%, commonly infections. Overall response rate was 63%; 26% CR were unaffected by IPSS. Median response duration 26.3months; overall survival was 28.1months. This combination azacitidine and thalidomide in clinically advanced MDS, CMML and low-blast AML was tolerable without unexpected toxicity and encouraging responses support further investigation of combination approaches with hypomethylating agent and immunomodulatory drug.

When should iron chelation therapy be considered in patients with myelodysplasia and other bone marrow failure syndromes with iron overload?

Despite the absence of a robust evidence base, there is growing consensus that effective treatment of iron overload leads to decreased morbidity and premature mortality in patients with good prognosis myelodysplastic syndromes (MDSs). Furthermore, new treatment modalities, including disease-modifying therapies (lenalidamide and azacytidine) and reduced intensity conditioning therapies for allogeneic blood stem cell transplants, are offering the prospect of longer survival for patients with traditionally less favourable prognosis MDS, who might also benefit from iron chelation. This article proposes assessment of patients with MDS and related bone marrow failure syndromes to determine suitability for iron chelation. Iron chelation therapy options and monitoring are discussed.

Safety and efficacy of pegfilgrastim compared to granulocyte colony stimulating factor (G-CSF) supporting a dose-intensive, rapidly cycling anti-metabolite containing chemotherapy regimen (Hyper-CVAD) for lymphoid malignancy

Pegfilgrastim (Neulasta) has proven efficacy as supportive therapy in a variety of 21-day chemotherapy regimens, but has not been studied in dose intensive, rapidly cycling regimens utilising cell-cycle active drugs (e.g. anti-metabolites) such as hyper-CVAD. This study examined whether pegfilgrastim was safe and lead to similar kinetics of neutrophil recovery as daily granulocyte colony stimulating factor (G-CSF). Using retrospective analysis, patients receiving pegfilgrastim (6 mg) were matched with controls (G-CSF 5 microg kg-1 per day) for a cycle of chemotherapy, prior chemotherapy, dose of cytarabine received, age (<60 or >60 years), diagnosis and bone marrow involvement. The primary endpoint was duration of grade IV neutropenia (absolute neutrophil count, ANC < 500 microl-1). Secondary endpoints included time to neutrophil recovery, incidence of febrile neutropenia, positive blood cultures and delay in subsequent chemotherapy. This study identified 124 pegfilgrastim supported cycles in 43 patients and successfully matched them to 124 G-CSF supported cycles from 38 patients treated between January 1999 and July 2005. There were no significant differences between pegfilgrastim and G-CSF groups in baseline or treatment-related variables. The median duration of grade IV neutropenia was 4 days in both groups (P = 0.55). Time to neutrophil recovery, incidence of febrile neutropenia, positive blood cultures and delay in subsequent chemotherapy were similar in both groups. Once per cycle dosing of pegfilgrastim appears safe and as effective as daily G-CSF for supporting the hyper-CVAD chemotherapy regimen.

Current status of new drugs for the treatment of patients with multiple myeloma

Multiple myeloma, a malignant disorder of plasma cells, is the second most common haematological malignancy. Although treatable, multiple myeloma remains incurable in virtually all cases, with a median survival of 3-4 years. Fortunately for patients with this disease, traditional treatment paradigms have been challenged with the emergence of a number of new therapies entering clinical practice over the last 6 years. In this review, we focus on the use of thalidomide (Thalidomide Pharmion; Boulder, CO, USA), lenalidomide (Revlimid; Celgene Corporation, Summit, NJ, USA) and bortezomib (Velcade; Janssen Pharmaceutica N.V., Belgium) in the treatment of myeloma. We present the current clinical experience with respect to efficacy and toxicity of these promising new agents and how the incorporation of these drugs with traditional therapies may improve the outcome for patients with multiple myeloma.

Treatment-related myelodysplasia following fludarabine combination chemotherapy

Although myelodysplasia (MDS) and secondary acute myeloid leukemia (sAML) are rare following fludarabine monotherapy, the risk of these diseases may potentially be increased when fludarabine is combined with cyclophosphamide or mitoxantrone due to synergistic effects on the inhibition of DNA repair. Among 137 patients treated with fludarabine combination regimens, ten patients developed MDS/sAML, including one who had received no other therapy. Six patients had abnormalities of chromosomes 5 and/or 7. The crude rate of MDS/sAML was 2.5% for previously untreated patients, and 9.3% for pretreated patients (p=0.28). The rate of MDS/sAML following fludarabine combination therapy is higher than that previously reported for fludarabine monotherapy.

Differentially expressed messenger RNA isoforms of the human estrogen receptor-alpha gene are generated by alternative splicing and promoter usage

The isolation and characterization of several new human estrogen receptor-alpha (hERalpha) mRNAs are described. Together with those previously identified, they give rise to a total of six hERalpha mRNA isoforms (A-F hERalpha mRNAs). Produced from a single hERalpha gene by multiple promoter usage, all these transcripts encode a common protein but differ in their 5'-untranslated region as a consequence of alternative splicing of five upstream exons (1B-1F). RT-PCR and S1 nuclease mapping analysis of these different hERalpha mRNA isoforms revealed a differential pattern of expression of the hERalpha gene in human tissues and cell types. The A hERalpha mRNA is the main isoform detected in mammary glands or in the tumor cell lines derived from this tissue. In endometrium, the predominant forms are the A and C hERalpha mRNA isoforms, whereas the C and F hERalpha mRNA isoforms are the major forms detected in ovary. Finally, high levels of the E hERalpha mRNA isoform are restricted to the liver with an increased expression in females. Taken together, our results demonstrate that the hERalpha gene is a complex genomic unit exhibiting alternative splicing and promoter usage in a tissue-specific manner.

Flecainide acetate for conversion of acute supraventricular tachycardia to sinus rhythm

The efficacy of intravenous flecainide acetate (maximum 2 mg/kg or 150 mg given at a rate of 15 mg/min) was assessed in patients with acute supraventricular tachycardia (SVT) (within 24 hours). Fifty patients were studied, 46 with spontaneous SVT and 4 with induced SVT at electrophysiologic assessment. Conversion to sinus rhythm was achieved within 45 minutes in 76%: in 25 patients with atrial fibrillation (76% conversion), 15 with atrioventricular (AV) nodal or AV reentrant tachycardia (100% conversion) and 10 with atrial flutter or atrial reentrant tachycardia (40% conversion). Adverse effects were noted in 21 patients (42%): paresthesia in 9, drowsiness in 8, nausea in 2, accelerated ventricular rate in 5, ventricular tachycardia in 1, sinus bradycardia in 1 and hypotension in 5. Adverse effects were associated with larger dosage and atrial flutter or atrial reentrant tachycardia. Thus, flecainide acetate is effective in converting to sinus rhythm acute atrial fibrillation and AV nodal and AV reentrant tachycardias, but not atrial flutter or atrial reentrant tachycardia.