Acute myeloid leukemia in the elderly: do we know who should be treated and how?

Dipeptidylpeptidase 4 promotes survival and stemness of acute myeloid leukemia stem cells

Leukemic-stem-cell-specific targeting may improve the survival of patients with acute myeloid leukemia (AML) by avoiding the ablative effects of standard regimens on normal hematopoiesis. Herein, we perform an unbiased screening of compounds targeting cell surface proteins and identify clinically used DPP4 inhibitors as strong suppressors of AML development in both murine AML models and primary human AML cells xenograft model. We find in retrovirus-induced AML mouse models that DPP4-deficient AML cell-transplanted mice exhibit delay and reversal of AML development, whereas deletion of DPP4 has no significant effect on normal hematopoiesis. DPP4 activates and sustains survival of AML stem cells that are critical for AML development in both human and animal models via binding with Src kinase and activation of nuclear factor κB (NF-κB) signaling. Thus, inhibition of DPP4 is a potential therapeutic strategy against AML development through suppression of survival and stemness of AML cells.

Current and Emerging Techniques for Diagnosis and MRD Detection in AML: A Comprehensive Narrative Review

Acute myeloid leukemia (AML) comprises a group of hematologic neoplasms characterized by abnormal differentiation and proliferation of myeloid progenitor cells. AML is associated with poor outcome due to the lack of efficient therapies and early diagnostic tools. The current gold standard diagnostic tools are based on bone marrow biopsy. These biopsies, apart from being very invasive, painful, and costly, have low sensitivity. Despite the progress uncovering the molecular pathogenesis of AML, the development of novel detection strategies is still poorly explored. This is particularly important for patients that check the criteria for complete remission after treatment, since they can relapse through the persistence of some leukemic stem cells. This condition, recently named as measurable residual disease (MRD), has severe consequences for disease progression. Hence, an early and accurate diagnosis of MRD would allow an appropriate therapy to be tailored, improving a patient's prognosis. Many novel techniques with high potential in disease prevention and early detection are being explored. Among them, microfluidics has flourished in recent years due to its ability at processing complex samples as well as its demonstrated capacity to isolate rare cells from biological fluids. In parallel, surface-enhanced Raman scattering (SERS) spectroscopy has shown outstanding sensitivity and capability for multiplex quantitative detection of disease biomarkers. Together, these technologies can allow early and cost-effective disease detection as well as contribute to monitoring the efficiency of treatments. In this review, we aim to provide a comprehensive overview of AML disease, the conventional techniques currently used for its diagnosis, classification (recently updated in September 2022), and treatment selection, and we also aim to present how novel technologies can be applied to improve the detection and monitoring of MRD.

Acetylshikonin induces autophagy-dependent apoptosis through the key LKB1-AMPK and PI3K/Akt-regulated mTOR signalling pathways in HL-60 cells

Acetylshikonin (ASK) is a natural naphthoquinone derivative of traditional Chinese medicine Lithospermum erythrorhyzon. It has been reported that ASK has bactericidal, anti‐inflammatory and antitumour effects. However, whether ASK induces apoptosis and autophagy in acute myeloid leukaemia (AML) cells and the underlying mechanism are still unclear. Here, we explored the roles of apoptosis and autophagy in ASK‐induced cell death and the potential molecular mechanisms in human AML HL‐60 cells. The results demonstrated that ASK remarkably inhibited the cell proliferation, viability and induced apoptosis in HL‐60 cells through the mitochondrial pathway, and ASK promoted cell cycle arrest in the S‐phase. In addition, the increased formation of autophagosomes, the turnover from light chain 3B (LC3B) I to LC3B II and decrease of P62 suggested the induction of autophagy by ASK. Furthermore, ASK significantly decreased PI3K, phospho‐Akt and p‐p70S6K expression, while enhanced phospho‐AMP‐activated protein kinase (AMPK) and phospho‐liver kinase B1(LKB1) expression. The suppression of ASK‐induced the conversion from LC3B I to LC3B II caused by the application of inhibitors of AMPK (compound C) demonstrated that ASK‐induced autophagy depends on the LKB1/AMPK pathway. These data suggested that the autophagy induced by ASK were dependent on the activation of LKB1/AMPK signalling and suppression of PI3K/Akt/mTOR pathways. The cleavage of the apoptosis‐related markers caspase‐3 and caspase‐9 and the activity of caspase‐3 induced by ASK were markedly reduced by inhibitor of AMPK (compound C), an autophagy inhibitor 3‐methyladenine (3‐MA) and another autophagy inhibitor chloroquine (CQ). Taken together, our data reveal that ASK‐induced HL‐60 cell apoptosis is dependent on the activation of autophagy via the LKB1/AMPK and PI3K/Akt‐regulated mTOR signalling pathways.

Age and remission induction therapy for acute myeloid leukemia: An analysis of data from the Korean acute myeloid leukemia registry

Objective

The clinical characteristics and therapeutic strategy in acute myeloid leukemia (AML) are influenced by patients’ age. We evaluated the impact of age on remission induction therapy for AML.

Methods

We retrospectively analyzed 3,011 adult AML patients identified from a nationwide database between January 2007 and December 2011.

Results

Three hundred twenty-nine (10.9%) acute promyelocytic leukemia (APL) and 2,682 (89.1%) non-APL patients were analyzed. The median age was 51 years and 55% of patients were male. Six hundred twenty-three patients (21%) were at favorable risk, 1522 (51%) were at intermediate risk, and 743 (25%) were at poor risk. As the age increased, the proportion of those at favorable risk and who received induction chemotherapy decreased. After induction therapy, complete response (CR) was achieved in 81.5% (243/298) of APL and 62.4% (1,409/2,258) of non-APL patients; these rates decreased as the age increased, with an obvious decrement in those older than 60 years. The median overall survival of non-APL patients was 18.7 months, while that of APL patients was not reached, with a 75% five-year survival rate.

Conclusions

Age impacts both the biology and clinical outcomes of AML patients. Further studies should confirm the role of induction remission chemotherapy by age group.

The prognostic factors and efficacy of induction chemotherapy in elderly patients with acute myeloid leukemia

BACKGROUND AND OBJECTIVE

Acute myeloid leukemia (AML) is the most common form of hematological malignancy in adults. We aimed to investigate the efficacy of different treatment measures and prognostic factors for elderly patients with AML.

METHODS

The clinical data of 65 newly diagnosed elderly patients with AML were retrospectively analyzed. Among them, 45 patients received induction chemotherapy including standard cytarabine regimen (n = 21) and low dose cytarabine regimen (n = 24), and 20 patients received palliative treatment. The efficacy and prognosis were compared between the groups.

RESULTS

There were no statistical differences in complete remission, overall survival and the 6-month disease-free survival rates between standard cytarabine group and low dose cytarabine group (P = 0.675, P = 0.775, P = 0.751, respectively). Significant difference in median overall survival and overall survival rate were detected (P < 0.001, P = 0.031, respectively), but no significant difference in early death rate (P = 0.238) was found between induction chemotherapy group and palliative treatment group. Multivariate analysis showed that the white blood cells count ≥ 100.0 × 10⁹/L was associated with early death.

CONCLUSIONS

The induction chemotherapy did not increase the early mortality. The low dose cytarabine regimen can be used as the first-line choice for elderly acute myeloid leukemia patients who are not suitable for intensive chemotherapy.

Outcomes of decitabine treatment for newly diagnosed acute myeloid leukemia in older adults​

PURPOSE

We evaluated the outcomes of decitabine as first-line treatment in older patients with acute myeloid leukemia (AML) and investigated the predictors, including a baseline mini nutritional assessment short form (MNA-SF) score, of response and survival.

PATIENTS AND METHODS

Between 2010 and 2018, 96 AML patients aged 65 and above who received decitabine treatment at 6 centers in Korea were retrospectively evaluated. Response rates, hematologic improvements (HI), progression-free survival (PFS), and overall survival (OS) were analyzed.

RESULTS

The median age at diagnosis was 73.9 years, and the median number of decitabine treatments administered to the patients was 4 (range, 1-29). Of 85 patients, 15 patients (17.6%) achieved complete remission (CR) or CR with incomplete blood count recovery. Twelve patients (14.1%) showed partial remission (PR), and 18 (21.2%) demonstrated HI without an objective response. The median PFS and OS were 7.0 (95% confidence interval [CI], 4.9-9.0) and 10.6 (95% CI, 7.7-13.5%) months, respectively. In multivariate analyses, MNA-SF score ≥ 8 and the absence of peripheral blood (PB) blasts were significant predictors for improved PFS and OS.

CONCLUSIONS

For older patients with newly diagnosed AML, a high MNA-SF score and the absence of PB blasts were independently associated with improved survival.

Decitabine combined with CAG regimen in the treatment of elderly patients with acute myeloid leukemia

Objective:

To analyze the efficacy and safety of decitabine combined with CAG ((cytarabine + aclacinomycin + granulocyte colony stimulating factor)) regimen and CAG regimen alone in the treatment of elderly acute myeloid leukemia.

Methods:

96 elderly patients with acute myeloid leukemia who were admitted to our hospital from July 2015 to July 2017 were randomly divided into an observation group and a control group, 48 cases in each group. The patients in the control group were treated with CAG regimen, while the patients in the observation group were treated with decitabine on the basis of the control group. The clinical curative effect, changes of immune indicators, occurrence of adverse reactions and survival rate at different time after treatment were compared between the two groups.

Results:

The total effective rate of the observation group was significantly higher than that of the control group (P<0.05). After treatment, the indicators of cellular immunity in the two groups were significantly lower than those before treatment, and the indicators of cellular immunity in the observation group were significantly lower than those in the control group (P<0.05). There was no significant difference in the incidence of adverse reactions between the two groups (P>0.05). The 9-month survival rate and 1-year survival rate in the observation group were significantly higher than those in the control group (P<0.05).

Conclusion:

The combination of decitabine and CAG regimen is effective in the treatment of elderly patients with acute myeloid leukemia. The therapy can fully inhibit cellular immune function and improve long-term survival rate, and its safety has a small difference with that of CAG regimen alone. It is worth clinical promotion.

Mebendazole for Differentiation Therapy of Acute Myeloid Leukemia Identified by a Lineage Maturation Index

Accurate assessment of changes in cellular differentiation status in response to drug treatments or genetic perturbations is crucial for understanding tumorigenesis and developing novel therapeutics for human cancer. We have developed a novel computational approach, the Lineage Maturation Index (LMI), to define the changes in differentiation state of hematopoietic malignancies based on their gene expression profiles. We have confirmed that the LMI approach can detect known changes of differentiation state in both normal and malignant hematopoietic cells. To discover novel differentiation therapies, we applied this approach to analyze the gene expression profiles of HL-60 leukemia cells treated with a small molecule drug library. Among multiple drugs that significantly increased the LMIs, we identified mebendazole, an anti-helminthic clinically used for decades with no known significant toxicity. We tested the differentiation activity of mebendazole using primary leukemia blast cells isolated from human acute myeloid leukemia (AML) patients. We determined that treatment with mebendazole induces dramatic differentiation of leukemia blast cells as shown by cellular morphology and cell surface markers. Furthermore, mebendazole treatment significantly extended the survival of leukemia-bearing mice in a xenograft model. These findings suggest that mebendazole may be utilized as a low toxicity therapeutic for human acute myeloid leukemia and confirm the LMI approach as a robust tool for the discovery of novel differentiation therapies for cancer.

Association of Mouse Double Minute 2 -309T>G Polymorphism with Acute Myeloid Leukemia in an Iranian Population: A Case- Control Study

Background:

Genetic factors play a substantial role in acute myeloid leukemia (AML) etiology. Overexpression of the mousedouble minute 2 (MDM2) gene has been explored in many tumors. However, the role of MDM2 -309T>G (rs2279744) polymorphism in AML remains unclear. We have performed this study to examine the association of MDM2 -309T>G with AML in an Iranian population.

Methods:

We have examined the association of N MDM2 -309T>G polymorphism in 73 cases diagnosed with AML and 80 healthy controls by tetra-primer amplification refractory mutation system (ARMS) PCR assay. Odds ratios (OR) and 95% confidence intervals (CI) were calculated on the risk genotypes and alleles.

Results:

The TT, GG and GG genotypes of MDM2 -309T>G polymorphism in patients were 32.9%, 23.2% and 43.9%, while in controls were 86.2%, 7.5% and 6.3%, respectively. Moreover, Frequency of mutant allele (G) was 55.6% in cases with AML and 10.0% in controls. The mutant homozygote genotype (GG) was associated with an increased susceptibility to AML (OR 1.471; 95% CI: 1.062-1.844; p=0.004).

Conclusion:

Our results showed that the MDM2 -309T>G polymorphism was significantly associated with increased risk of AML in the Iranian population. Thus, the MDM2 -309T>G polymorphism might be useful genetic susceptibility factors in the pathogenesis of AML.

Checkpoint inhibitors and acute myelogenous leukemia: promises and challenges

INTRODUCTION

Immunity, for treatment of acute myelogenous leukemia (AML), has been leveraged historically in the form of allogeneic stem cell transplantation. Checkpoint inhibitors (CPI) as positive modulators of immune response have been recent major breakthroughs in solid tumors. Areas covered: Emerging concepts and clinical data with CPIs in acute Myeloid Leukemia - the focus of this review- will be discussed. CPIs can potentially be effective in absence of 'actionable' mutations and are expected to be effective against poor-risk AML. Immune inhibitory checkpoint molecules are upregulated in both de novo and relapsed AML. Similar data also suggest role of checkpoint molecules in mediating resistance particularly to hypomethylating agent (HMA) therapy, which can potentially be reversed by using checkpoint inhibitors. Expert commentary: Ongoing clinical trials in combination with HMAs are showing early promise, with doubling of response than that seen in historic controls. The optimal combinations of CPIs and the optimal space that they will fit in the continuum of AML therapies need lot of in depth work.

[Treatment of 30 elderly patients with advanced myeloid neoplasm by allogeneic hematopoietic stem cell transplantation]

Objective: To evaluate the efficacy of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for elderly patients with advanced myeloid neoplasm. Methods: From September 2014 to September 2017, 30 consecutive hospitalized 50-plus-year-old myeloid neoplasm patients were retrospectively analyzed. At the time of transplantation, 6 patients reached complete remission and the others remained no remission after treatment. The donors were identical sibling (12), matched unrelated (6) and haploidentical family member (12), respectively. 18 patients received RIC while 12 patients received MAC conditioning regiments consisted of Busulfan, cytarabine, fludarabine or clarithromycin±TBI, respectively. Results: Five patients died early in the conditioning stage, 24 patients successfully engrafted. The median time of neutrophil engraftment was 14(10-18) d, whereas platelet engraftment was 15(10-19) d. Six cases (25%) experienced aGVHD grades Ⅱ, 8 cases (32%) cGVHD, including moderate to severe cGVHD in 2 cases (8%). Seven, 7 and 5 cases developed CMV viremia, pneumonia and herpeszoster, respectively after transplantation, but no patients died of infections. The median follow-up time of the patients was 7(0.5-38) months. Twenty-one patients were still alive. The estimated 2 years OS and LFS were 62.5% (95% CI 39.2%-85.8%) and 59.2% (95% CI 26.9%-91.5%), respectively. Univariate analysis showed that HCT-CI was the only factor influencing OS. Conclusion: Allogeneic hematopoietic stem cell transplantation could improve the survival of elderly patients with myeloid neoplasm.

miR-126 promotes the growth and proliferation of leukemia stem cells by targeting DNA methyltransferase 1

Previous studies have showed that the interaction between microRNAs (miRNAs) and leukemia stem cells (LSCs) may be a cause of drug resistance of acute myeloid leukemia (AML). However, whether miR-126 participates in the pathogenesis of AML remains unclear. In our study, we first examined the expression of miR-126 in CD34+ or CD34- cells isolated from blood samples and LSC cell line: KG-1a-LSCs and MOLM13-LSCs by qRT-PCR analysis. Then miR-126 inhibitor and mimics were applied to evaluate the roles of miR-126 in cell proliferation of LSC cell lines using CCK-8 assay and Ki-67 staining. Moreover, flow cytometry analysis was used to assess the apoptosis of LSC cell lines treated with miR-126 inhibitor of mimics. In addition, we analyzed the relationship between miR-126 and DNA methyltransferase 1 (DNMT1) by bioinformatics analysis and dual-luciferase reporter assay. Western blot analysis was applied to examine the protein expression level of DNMT1 in miR-126 mimics treated LSC cells. Results showed that miR-126 expression was significantly higher in CD34+ cells and KG-1a-LSCs and MOLM13-LSCs. Knockdown of miR-126 in KG-1a-LSCs and MOLM13-LSCs inhibited cell proliferation, and promoted apoptosis. miR-126 could regulate DNA methyltransferase 1 (DNMT1) expression by directly binding to it. In conclusion, these findings suggested that miR-126 may promote cell proliferation of LSCs by targeting DNMT1.

Genetics of acute myeloid leukemia in the elderly: mutation spectrum and clinical impact in intensively treated patients aged 75 years or older

A cute myeloid leukemia is a disease of the elderly (median age at diagnosis, 65-70 years). The prognosis of older acute myeloid leukemia patients is generally poor. While genetic markers have become important tools for risk stratification and treatment selection in young and middle-aged patients, their applicability in very old patients is less clear. We sought to validate existing genetic risk classification systems and identify additional factors associated with outcomes in intensively treated patients aged ≥75 years. In 151 patients who received induction chemotherapy in the AMLCG-1999 trial, we investigated recurrently mutated genes using a targeted sequencing assay covering 64 genes. The median number of mutated genes per patient was four. The most commonly mutated genes were TET2 (42%), DNMT3A (35%), NPM1 (32%), SRSF2 (25%) and ASXL1 (21%). The complete remission rate was 44% and the 3-year survival was 21% for the entire cohort. While adverse-risk cytogenetics (MRC classification) were associated with shorter overall survival (P=0.001), NPM1 and FLT3-ITD mutations (present in 18%) did not have a significant impact on overall survival. Notably, none of the 13 IDH1-mutated patients (9%) reached complete remission. Consequently, the overall survival of this subgroup was significantly shorter than that of IDH1-wildtype patients (P<0.001). In summary, even among very old, intensively treated, acute myeloid leukemia patients, adverse-risk cytogenetics predict inferior survival. The spectrum and relevance of driver gene mutations in elderly patients differs from that in younger patients. Our data implicate IDH1 mutations as a novel marker for chemorefractory disease and inferior prognosis. (AMLCG-1999 trial: clinicaltrials.gov identifier, NCT00266136).

Clinical decision making in cancer care: a review of current and future roles of patient age

Background

Patient age is among the most controversial patient characteristics in clinical decision making. In personalized cancer medicine it is important to understand how individual characteristics do affect practice and how to appropriately incorporate such factors into decision making. Some argue that using age in decision making is unethical, and how patient age should guide cancer care is unsettled. This article provides an overview of the use of age in clinical decision making and discusses how age can be relevant in the context of personalized medicine.

Methods

We conducted a scoping review, searching Pubmed for English references published between 1985 and May 2017. References concerning cancer, with patients above the age of 18 and that discussed age in relation to diagnostic or treatment decisions were included. References that were non-medical or concerning patients below the age of 18, and references that were case reports, ongoing studies or opinion pieces were excluded. Additional references were collected through snowballing and from selected reports, guidelines and articles.

Results

Three hundred and forty-seven relevant references were identified. Patient age can have many and diverse roles in clinical decision making: Contextual roles linked to access (age influences how fast patients are referred to specialized care) and incidence (association between increasing age and increasing incidence rates for cancer); patient-relevant roles linked to physiology (age-related changes in drug metabolism) and comorbidity (association between increasing age and increasing number of comorbidities); and roles related to interventions, such as treatment (older patients receive substandard care) and outcome (survival varies by age).

Conclusions

Patient age is integrated into cancer care decision making in a range of ways that makes it difficult to claim age-neutrality. Acknowledging this and being more transparent about the use of age in decision making are likely to promote better clinical decisions, irrespective of one’s normative viewpoint. This overview also provides a starting point for future discussions on the appropriate role of age in cancer care decision making, which we see as crucial for harnessing the full potential of personalized medicine.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4456-9) contains supplementary material, which is available to authorized users.

Comorbidity, Physical Function, and Quality of Life in Older Adults with Acute Myeloid Leukemia

Purpose of review

To describe the pathology, impact of comorbidities, functional limitations, symptoms, and quality of life (QOL) related to treatment of acute myeloid leukemia (AML) in older adults.

Recent findings

AML is a rare aggressive hematologic disease that occurs most often in older adults. The prognosis for older patients with AML is markedly worse due to genetic mutations and patient characteristics such as comorbidities and functional limitations. Patient characteristics may influence treatment decisions, as well as impact symptoms, functional ability, health-related outcomes and (QOL).

Summary

As the population continues to age, the number of people diagnosed with AML is expected to increase. Better management of comorbidities is imperative to improving QOL and other treatment related outcomes. Prospective, longitudinal and multi-site studies are warranted to further understand the interaction between these characteristics on symptoms, outcomes and QOL.

CD25 as an adverse prognostic factor in elderly patients with acute myeloid leukemia

OBJECTIVES

CD25 has been reported to be highly expressed in leukemia stem cells and correlated with adverse outcomes in young patients with acute myeloid leukemia (AML). However, the significance of CD25 expression in elderly patients with AML has not yet been investigated.

METHODS

We retrospectively analyzed 154 newly diagnosed AML patients aged 60 years or over by flow cytometry.

RESULTS

CD25-positive AML was characterized by high white blood cell counts, secondary AML, rare favorable karyotypes, and positivity for CD34 and CD7 antigens, compared with CD25-negative AML. CD25 positivity was significantly correlated with an inferior complete remission (CR), event-free survival (EFS), and overall survival. Multivariate analysis showed CD25 positivity to be a significant prognostic predictor of CR and EFS. A regimen of low-dose cytarabine and aclarubicin combined with granulocyte-colony-stimulating factor (CAG) led to higher CR rates in the CD25-positive AML patients than intensive chemotherapies. CD25 expression was increased at relapse and in the development of leukemic status from myelodysplastic syndrome or myeloproliferative neoplasm.

DISCUSSION

An effective treatment strategy for elderly patients with CD25-positive AML has not been established. Further studies are needed to evaluate the effect of a CAG regimen and allogenic stem cell transplantation in patients.

CONCLUSION

CD25 is an independent prognostic factor in elderly AML patients. Alternative therapies for CD25-positive elderly AML patients are needed.

Alantolactone selectively ablates acute myeloid leukemia stem and progenitor cells

BACKGROUND

The poor outcomes for patients diagnosed with acute myeloid leukemia (AML) are largely attributed to leukemia stem cells (LSCs) which are difficult to eliminate with conventional therapy and responsible for relapse. Thus, new therapeutic strategies which could selectively target LSCs in clinical leukemia treatment and avoid drug resistance are urgently needed. However, only a few small molecules have been reported to show anti-LSCs activity.

METHODS

The aim of the present study was to identify alantolactone as novel agent that can ablate acute myeloid leukemia stem and progenitor cells from AML patient specimens and evaluate the anticancer activity of alantolactone in vitro and in vivo.

RESULTS

The present study is the first to demonstrate that alantolactone, a prominent eudesmane-type sesquiterpene lactone, could specifically ablate LSCs from AML patient specimens. Furthermore, in comparison to the conventional chemotherapy drug, cytosine arabinoside (Ara-C), alantolactone showed superior effects of leukemia cytotoxicity while sparing normal hematopoietic cells. Alantolactone induced apoptosis with a dose-dependent manner by suppression of NF-kB and its downstream target proteins. DMA-alantolactone, a water-soluble prodrug of alantolactone, could suppress tumor growth in vivo.

CONCLUSIONS

Based on these results, we propose that alantolactone may represent a novel LSCs-targeted therapy and eudesmane-type sesquiterpene lactones offer a new scaffold for drug discovery towards anti-LSCs agents.

Efficacy of Compound Kushen Injection in Combination with Induction Chemotherapy for Treating Adult Patients Newly Diagnosed with Acute Leukemia

We assessed the clinical effectiveness and safety of CKI (compound Kushen injection) plus standard induction chemotherapy for treating adult acute leukemia (AL). We randomly assigned 332 patients with newly diagnosed AL to control (n = 165, receiving DA (daunorubicin and cytarabine) or hyper-CVAD (fractionated cyclophosphamide, doxorubicin, vincristine, and dexamethasone)) or treatment (n = 167, receiving CKI and DA or hyper-CVAD) groups. Posttreatment, treatment group CD3+, CD4+, CD4+/CD8+, natural killer (NK) cell, and immunoglobulin (IgG, IgA, and IgM) levels were significantly higher than those of the control group (p < 0.05), and CD8+ levels were lower in the treatment group than in the control group (p < 0.05). Treatment group interleukin- (IL-) 4 and IL-10 levels were significantly higher compared to the control posttreatment (both p < 0.05) as were complete remission, overall response, and quality of life (QoL) improvement rates (p < 0.05). The control group had more incidences of grade 3/4 hematologic and nonhematologic toxicity (p < 0.05). Responses to induction chemotherapy, QoL improvement, and adverse events incidence between control group patients with acute myeloid leukemia and acute lymphocytic leukemia were not significantly different. CKI plus standard induction chemotherapy is effective and safe for treating AL, possibly by increasing immunologic function.

Acute myeloid leukemia: advancing clinical trials and promising therapeutics

Recent progress in understanding the biology of acute myeloid leukemia (AML) and the identification of targetable driver mutations, leukemia specific antigens and signal transduction pathways has ushered in a new era of therapy. In many circumstances the response rates with such targeted or antibody-based therapies are superior to those achieved with standard therapy and with decreased toxicity. In this review we discuss novel therapies in AML with a focus on two major areas of unmet need: (1) single agent and combination strategies to improve frontline therapy in elderly patients with AML and (2) molecularly targeted therapies in the frontline and salvage setting in all patients with AML.

A phase II study of decitabine and gemtuzumab ozogamicin in newly diagnosed and relapsed acute myeloid leukemia and high-risk myelodysplastic syndrome

Decitabine may open the chromatin structure of leukemia cells making them accessible to the calicheamicin epitope of gemtuzumab ozogamicin (GO). A total of 110 patients (median age 70 years; range 27-89 years) were treated with decitabine and GO in a trial designed on model-based futility to accommodate subject heterogeneity: group 1: relapsed/refractory acute myeloid leukemia (AML) with complete remission duration (CRD) <1 year (N=28, 25%); group 2: relapsed/refractory AML with CRD ⩾1 year (N=5, 5%); group 3: untreated AML unfit for intensive chemotherapy or untreated myelodysplastic syndrome (MDS) or untreated myelofibrosis (MF; N=57, 52%); and group 4: AML evolving from MDS or relapsed/refractory MDS or MF (N=20, 18%). Treatment consisted of decitabine 20 mg/m(2) daily for 5 days and GO 3 mg/m(2) on day 5. Post-induction therapy included five cycles of decitabine+GO followed by decitabine alone. Complete remission (CR)/CR with incomplete count recovery was achieved in 39 (35%) patients; group 1= 5/28 (17%), group 2=3/5 (60%), group 3=24/57 (42%) and group 4=7/20 (35%). The 8-week mortality in groups 3 and 4 was 16% and 10%, respectively. Common drug-related adverse events included nausea, mucositis and hemorrhage. Decitabine and GO improved the response rate but not overall survival compared with historical outcomes in untreated AML ⩾60 years.

Azacitidine in the treatment of older patients affected by acute myeloid leukemia: A report by the Rete Ematologica Pugliese (REP)

The optimal treatment of older patients (>65 years) with acute myeloid leukemia (AML) remains challenging in daily clinical practice; a choice has to be made between intensive chemotherapy and best supportive care. To guide physicians, several prognostic factors have been identified and risk scores developed. Recently, the DNA methyltransferase inhibitor azacitidine has become available for use in MDS and AML patients with up to 30% bone marrow blasts. However, limited data are available on the outcome of older unfit AML patients, regardless of their bone marrow blast count. We retrospectively analyzed the outcome of 90 newly diagnosed older unfit AML patients in 9 Institutions from the Apulia Region (REP). Responder patients (evaluation performed after 4 cycles of treatment even in cases of primary failure) showed a better overall survival than non responders (23 vs 6 months, p<.001). ECOG PS≥2 seems to be correlated with OS in multivariate analysis, while neither primary treatment failure (documented after 2 cycles) nor bone marrow blast count were correlated with a worse overall survival either at univariate (22 vs 29 months, p=.ns; 16 vs 19 months, p=.ns) or multivariate analysis. Overall, the results of our retrospective analysis seem to confirm the efficacy of AZA treatment for this unfit AML patients setting, in terms of both CR and OS, regardless of the bone marrow blasts count, while primary treatment failure should not lead to a discontinuation of treatment.

Oligonucleotide aptamer-drug conjugates for targeted therapy of acute myeloid leukemia

Oligonucleotide aptamers can specifically bind biomarkers on cancer cells and can be readily chemically modified with different functional molecules for personalized medicine. To target acute myeloid leukemia (AML) cells, we developed a single-strand DNA aptamer specific for the biomarker CD117, which is highly expressed on AML cells. Sequence alignment revealed that the aptamer contained a G-rich core region with a well-conserved functional G-quadruplex structure. Functional assays demonstrated that this synthetic aptamer was able to specifically precipitate CD117 proteins from cell lysates, selectively bound cultured and patient primary AML cells with high affinity (Kd < 5 nM), and was specifically internalized into CD117-expressing cells. For targeted AML treatment, aptamer-drug conjugates were fabricated by chemical synthesis of aptamer (Apt) with methotrexate (MTX), a central drug used in AML chemotherapy regimens. The formed Apt-MTX conjugates specifically inhibited AML cell growth, triggered cell apoptosis, and induced cell cycle arrest in G1 phase. Importantly, Apt-MTX had little effect on CD117-negative cells under the same treatment conditions. Moreover, exposure of patient marrow specimens to Apt-MTX resulted in selective growth inhibition of primary AML cells and had no toxicity to off-target background normal marrow cells within the same specimens. These findings indicate the potential clinical value of Apt-MTX for targeted AML therapy with minimal to no side effects in patients, and also open an avenue to chemical synthesis of new, targeted biotherapeutics.

The NEDD8-activating enzyme inhibitor MLN4924 disrupts nucleotide metabolism and augments the efficacy of cytarabine

PURPOSE

New therapies are urgently needed for patients with acute myelogenous leukemia (AML). The novel NEDDylation inhibitor MLN4924 (pevonedistat) has demonstrated significant preclinical antileukemic activity and preliminary efficacy in patients with AML in a phase I trial. On the basis of its antimyeloid and DNA-damaging properties, we investigated the ability of MLN4924 to augment conventional cytarabine (ara-C) therapy.

EXPERIMENTAL DESIGN

The effects of MLN4924/ara-C on viability, clonogenic survival, apoptosis, DNA damage, and relevant pharmacodynamic targets were determined. The efficacy and pharmacodynamics of MLN4924/ara-C were assessed in an AML xenograft model.

RESULTS

Cotreatment of AML cell lines and primary patient specimens with MLN4924 and ara-C led to diminished clonogenic survival, increased apoptosis, and synergistic levels of DNA damage. RNAi demonstrated that stabilization of CDT-1, an event previously shown to mediate the DNA-damaging effects of MLN4924, was not a key regulator of sensitivity to the MLN4924/ara-C combination. Global metabolic profiling revealed that MLN4924 disrupts nucleotide metabolism and depletes intracellular nucleotide pools in AML cells. Subsequent experiments showed that MLN4924 promoted increased incorporation of ara-C into the DNA of AML cells. This effect as well as the therapeutic benefit of the MLN4924/ara-C combination was antagonized by supplementation with the nucleotide building block ribose. Coadministration of MLN4924 and ara-C to mice bearing FLT3-ITD(+) AML xenografts stably inhibited disease progression and increased DNA damage in vivo.

CONCLUSIONS

Our findings provide strong rationale for clinical investigation of the MLN4924/ara-C combination and establish a new link between therapeutic inhibition of NEDDylation and alterations in nucleotide metabolism. Clin Cancer Res; 21(2); 439-47. ©2014 AACR.

Treating acute myeloid leukemia in older adults

Acute myeloid leukemia (AML) is a disease of older adults, with a median age of 67 years at presentation. In the past, only a third of older patients (defined as individuals older than 60-65 years of age) with AML received definitive therapy for their disease due to concerns about their overall fitness and potential treatment-related mortality. However, compelling epidemiological data have shown unequivocally that older AML patients up to 80 years old both tolerate and survive longer after therapy than their untreated counterparts. Current therapeutic options for elderly individuals with AML include intensive chemotherapy with a cytarabine and anthracycline backbone, hypomethylating agents (decitabine and azacitidine), low-dose cytarabine, investigational agents, and supportive care with hydroxyurea and transfusions. Over the last few years, there has been increasing debate regarding the appropriate therapeutic approach to take in older adults given the diversity of the geriatric patient population and heterogeneous AML disease biology. This article discusses how performance status, comorbidities, disease characteristics, quality of life concerns, and long-term treatment goals affect the selection of appropriate therapy for older adults with AML. Risks and benefits of each treatment approach based on the most recent medical literature are discussed. Finally, a treatment algorithm summarizing these data and incorporating geriatric assessment and molecular and cytogenetic markers predictive of therapeutic response is proposed to aid in the clinical decision-making process.