Intensive induction chemotherapy with regimen containing intermediate dose cytarabine in the treatment of de novo acute myeloid leukemia

Time point-dependent concordance and prognostic significance of flow cytometry and real time quantitative PCR for measurable/minimal residual disease detection in acute myeloid leukemia with t(8;21)(q22;q22.1)

BACKGROUND

Flow cytometry (FCM) and PCR are reliable methods for assessing minimal residual disease (MRD) in acute myeloid leukemia with t(8;21)(q22;q22.1). The aim of this study was to analyze the concordant rate of these two methods and their prognostic significance.

METHODS

PCR and FCM were simultaneously used for MRD analysis at four different time points on 450 BM samples from 124 patients with AML with t(8;21)(q22;q22.1). The four monitoring time points included post-induction (first), after the first consolidation (second) and the second consolidation (third), and at the end of chemotherapy or before Allo/Auto stem cell transplantation (fourth).

RESULTS

The concordant rates of the two methods were 33.06%, 25.81%, 49.59%, and 75.31%, respectively, and the main discordant cases were FCM-/PCR+ cases. At all monitoring time points, the MRD level ≥ 10^-4 by FCM indicated a poor 3-year Relapse-Free Survival (RFS) (p < 0.001). More than 2-log MRD reduction by PCR after induction and more than 3-log reduction by PCR after the first consolidation remained the significant predictors of better RFS (p < 0.001). After the second consolidation, the negative MRD by PCR (<10-5) was also associated with improved RFS (p = 0.002). A > 1-log increase in PCR can effectively predict recurrence after molecular remission (p < 0.001). In the multivariate analysis, MRD≥0.01% by. FCM and less than 2-log MRD reduction by PCR after induction remained the significant predictors of poor RFS (p < 0.05).

CONCLUSIONS

FCM+ always indicates a poor prognosis. Sequential monitoring by PCR is of significance for evaluating prognosis. Our findings suggest a complementary role of two analyses in optimizing risk stratification in clinical practice.

Optimized clinical application of minimal residual disease in acute myeloid leukemia with RUNX1-RUNX1T1

Minimal residual disease (MRD) levels monitored by polymerase chain reaction are associated with outcomes in acute myeloid leukemia with RUNX1-RUNX1T1. The objectives of our study were to quantitatively compare the predictive value of MRD reduction and absolute copies and assess the influence of other prognostic factors on MRD. A total of 224 consecutive patients with RUNX1-RUNX1T1 aged ≤55 years were included in the MRD study. Patients received different induction regimens including conventional- or intermediate-dose cytarabine plus low-dose daunorubicin and omacetaxine mepesuccinate or daunorubicin at 60 mg/m²/day on days 1-3. As continuous variables, both MRD reduction and absolute MRD level were significantly associated with cumulative incidence of relapse (CIR; hazard ratio [HR] = 1.610, 95% confidence interval [CI]: 1.370-1.890, p < 0.001, and HR = 1.170, 95% CI: 1.120-1.230, p < 0.001, respectively). For the CIR, the area under the curves (AUCs) of MRD reduction and absolute MRD level after the first consolidation chemotherapy were 0.629 and 0.629, respectively. Intermediate-dose cytarabine induction (HR = 0.494; p = 0.039 for CIR, HR, 0.451; p = 0.014 for RFS, and HR, 0.262; p = 0.006 for OS) remained significantly associated with outcomes after adjusting for MRD reduction after the first consolidation therapy (HR = 1.456, p < 0.001, for CIR; HR = 1.467, p = 0.001, for relapse-free survival; and HR = 1.468, p = 0.014, for overall survival) in multivariate analyses. In conclusion, the prognostic significance of MRD after the first consolidation therapy was influenced by the induction regimen in acute myeloid leukemia with RUNX1-RUNX1T1.

Efficacy of high-dose cytarabine and aclarubicin in combination with G-CSF regimen compared to intermediate/high-dose cytarabine and standard-dose cytarabine induction regimen for non-remission acute myeloid leukemia

BACKGROUND

Acute myeloid leukemia (AML) patients with non-remission (NR) after the first cycle of standard induction chemotherapy remain a challenge owing to poor response and tolerance to re-induction regimen. We retrospectively evaluated the efficacy and safety of three regimens in AML patients refractory to the first course of standard induction regimen.

MATERIALS AND METHODS

The three regimens consisted of (1) High-dose cytarabine, aclarubicin and granulocyte colony-stimulating factor (HD-CAG) regimen (n = 44); (2) intermediate/high-dose cytarabine (I/HDAC) regimen (n = 30); and (3) standard-dose cytarabine (SDAC) combination regimen that was identical to the first course of standard induction regimen (n = 27).

RESULTS

Results indicated that after the second course, the overall response (OR), i.e., complete remission [CR]+partial remission [PR]) rates in HD-CAG was higher than in the I/HDAC group (84.1% vs. 56.7%, P = 0.009), whereas the CR rates among 3 groups were not statistically different (P = 0.541). Meanwhile, the proportion of subjects reporting certain adverse effects in the HD-CAG group was lower than the I/HDAC or SDAC groups. There were no significant differences in overall survival (OS) and disease-free survival (DFS) rates among the 3 groups (P = 0.881 and P = 0.872, respectively).

CONCLUSION

Our preliminary results indicate that HD-CAG regimen may represent a better alternative option for AML patients with NR after the first course of standard induction chemotherapy.

[Prognostic significance of flow cytometric minimal residual disease in acute myeloid leukemia during aplasia]

Objective: To investigate the impact of minimal residual disease (MRD) by multiparameter flow cytometry (MPFC) during aplasia on efficacy and prognosis of de novo acute myeloid leukemia (AML) (non M(3)) patients. Methods: The MRD data by 8-color MPFC during aplasia (day 14-15 of induction therapy) in 85 de novo AML (non M(3)) patients and the MRD impact on efficacy and prognosis were retrospectively analyzed. Results: Data of 85 patients, including 42 males (49.4%) and 43 females (50.6%) , were collected, with a median age of 35 (15-54) years. The median MRD by MPFC during aplasia was 0.58% (0-81.11%) , and 70 (82.4%) patients achieved complete remission (CR) after first induction chemotherapy. The cutoff of MRD by receiver operating characteristic (ROC) analysis was 2.305% (Se= 0.867, Sp=0.800) . The CR rate after one course was significantly higher in patients with MRD<2.305% [96.6% (56/58) ]than in patients with MRD≥2.305%[51.9% (14/27) ] (χ(2)=22.348, P<0.001) ; no significant difference with respect to relapse-free survival rate (χ(2)=1.08, P=0.299) or overall survival rate (χ(2)=0.42, P=0.516) could be demonstrated for the comparison of the two groups. Multivariates analysis showed MRD divided by 2.305% was the only independent prognostic factor for CR after one course (OR= 21.560, 95% CI 4.129-112.579, P<0.001) . Conclusion: Flow cytometric MRD divided by 2.305% during aplasia could be a predictor of efficacy after first induction therapy in AML patients.

Cephalotaxus Alkaloids

Cephalotaxus alkaloids represent a family of plant secondary metabolites known for 60 years. Significant activity against leukemia in mice was demonstrated for extracts of Cephalotaxus. Cephalotaxine (CET) (1), the major alkaloid of this series was isolated from Cephalotaxus drupacea species by Paudler in 1963. The subsequent discovery of promising antitumor activity among new Cephalotaxus derivatives reported by Chinese, Japanese, and American teams triggered extensive structure elucidation and biological studies in this family. The structural feature of this cephalotaxane family relies mainly on its tetracyclic alkaloid backbone, which comprises an azaspiranic 1-azaspiro[4.4]nonane unit (rings C and D) and a benzazepine ring system (rings A and B), which is linked by its C3 alcohol function to a chiral oxygenated side chain by a carboxylic function alpha to a tetrasubstituted carbon center. The botanical distribution of these alkaloids is limited to the Cephalotaxus genus (Cephalotaxaceae). The scope of biological activities of the Cephalotaxus alkaloids is mainly centered on the antileukemic activity of homoharringtonine (HHT) (2), which in particular demonstrated marked benefits in the treatment of orphan myeloid leukemia and was approved as soon as 2009 by European Medicine Agency and by US Food and Drug Administration in 2012. Its exact mechanism of action was partly elucidated and it was early recognized that HHT (2) inhibited protein synthesis at the level of the ribosome machinery. Interestingly, after a latency period of two decades, the topic of Cephalotaxus alkaloids reemerged as a prolific source of new natural structures. To date, more than 70 compounds have been identified and characterized. Synthetic studies also regained attention during the past two decades, and numerous methodologies were developed to access the first semisynthetic HHT (2) of high purity suitable for clinical studies, and then high grade enantiomerically pure CET (1), HHT (2), and analogs.

Prior hypomethylating agent use lacks impact on clinical outcome in patients with secondary acute myeloid leukemia arising from myelodysplastic syndromes treated with standard induction chemotherapy

Patients with secondary acute myeloid leukemia (sAML) arising from prior myelodysplastic syndromes have poor prognosis. Anthracycline plus cytarabine (7 + 3) is a standard treatment option for patients who are fit for intensive therapy. In the present study, 22 of 96 sAML patients (23 %) were treated with 7 + 3 and achieved median overall survival (OS) of 9.8 months. Hypomethylating agents (HMA) were given for MDS in 6/22 (28 %) of the patients. When evaluating the prior HMA group, CR/CRi was 50 % for those with prior HMA exposure and 63 % for those without HMA exposure (P = 0.6). Median OS was 14 months for prior HMA exposure vs 10 months for no prior HMA (P = 0.9). The outcome of sAML patients who were treated with 7 + 3 continues to be poor. No statistical significant difference was found between response rates and mOS between prior HMA exposure or not. Additional larger studies are needed to confirm our results.

Association of ABCB1 polymorphisms with prognostic outcomes of anthracycline and cytarabine in Chinese patients with acute myeloid leukemia

PURPOSE

To investigate the influence of ABCB1 polymorphisms on prognostic outcomes in Chinese patients with de novo intermediate-risk acute myeloid leukemia (AML) and to examine the gene expression level in relation to the genetic variation.

METHODS

In total, 263 Chinese intermediate-risk AML patients treated with anthracycline and cytarabine were enrolled. G2677T, C1236T, and C3435T of the ABCB1 gene were analyzed by the allele-specific matrix-assisted laser desorption. Expression of ABCB1 messenger RNA (mRNA) was tested in 101 patients of known genotype and haplotype for ABCB1 polymorphisms. Basic clinical characteristics of these patients were collected from medical records.

RESULTS

Survival analysis showed that patients with AML (TTT haplotype) had a longer overall survival (OS) (p < 0.001, 29.2 months, 95 % confidence interval [CI], 26.9-31.5 months) and relapse-free survival (RFS) (p = 0.005, 21.8 months, 95 % CI, 19.5-24.0 months) compared with those without TTT haplotype (21.9 months, 95 % CI, 19.6-24.2 months; 16.5 months, 95 % CI, 14.6-18.5 months). After adjusting for age; gender; leukocyte count; hemoglobin level; platelet levels; French, American, and British classification; lactate dehydrogenase levels; Eastern Cooperative Oncology Group performance status; nucleophosmin gene; and fms-related tyrosine kinase 3 gene, the multivariate survival analysis showed that the TTT haplotype appeared to be a predicting factor for OS (p = 0.001, hazard ratio = 1.854, 95 % CI, 1.301-2.641) and RFS (p = 0.009, hazard ratio = 1.755, 95 % CI, 1.153-2.671). Moreover, a significant association between the TTT haplotype and relapse in AML patients was observed in this study (p = 0.002, odds ratio = 0.410, 95 % CI, 0.235-0.715). Gene expression level was significantly lower in patients with the TTT haplotype than in the patients with the other haplotypes (p = 0.004).

CONCLUSIONS

The findings suggested the TTT haplotype was possibly related to the OS, RFS, and relapse in Chinese patients with AML.

Long-term follow-up of homoharringtonine plus all-trans retinoic acid-based induction and consolidation therapy in newly diagnosed acute promyelocytic leukemia

We conducted a retrospective study to evaluate the efficacy of combining homoharringtonine (HHT) with all-trans-retinoic acid (ATRA)-based induction therapy, followed by three courses of consolidation chemotherapy and 2-year sequential maintenance therapy in acute promyelocytic leukemia (APL). Fifty-three patients were enrolled in the study. The complete remission (CR) rate was 100 %. No patient died during induction therapy. The 9-year event-free survival (EFS) and 9-year overall survival (OS) for all patients were 79.0 and 83.0 %, respectively. Outcome estimates according to the body mass index (BMI) were carried out. Twenty-three (43.4 %) were underweight/normal (BMI < 23.0 kg/m(2)), whereas 30 patients (56.6 %) were overweight/obese (BMI ≥ 23.0 kg/m(2)). Underweight/normal-weight patients had a 9-year OS of 100 %, compared with 73.0 % for overweight/obese patients (P = 0.044). These results indicate that HHT plus ATRA-based induction and consolidation therapy may be a highly efficacious treatment option for newly diagnosed APL. Increased BMI had an adverse prognostic impact in APL.

Association of nitric oxide synthase 3 (NOS3) 894 G>T polymorphism with prognostic outcomes of anthracycline in Chinese patients with acute myeloid leukaemia

The aim of the present study was to investigate the influence of the nitric oxide synthase 3 (NOS3) 894 G>T polymorphism on prognostic outcomes of anthracycline in Chinese patients with de novo intermediate-risk acute myeloid leukaemia (AML) and to examine the gene expression level in relation to genetic variation. In all, 225 Chinese patients with intermediate-risk AML (at the complete remission stage) treated with anthracycline were enrolled in the study. The 894 G>T polymorphism of the NOS3 gene was analysed by allele-specific matrix-assisted laser desorption ionization time-of-flight. Expression of NOS3 mRNA was tested in 72 patients of known genotype for NOS3 894 G>T. The clinical characteristics of these patients were obtained from medical records. Survival analysis showed that patients with AML (GG genotype) had a longer overall survival (OS; P = 0.006). After adjusting for age, gender, leucocyte count, haemoglobin level, platelet level, French, American and Britain (FAB) classification, lactate dehydrogenase levels, Eastern Cooperative Oncology Group Performance Status, nucleophosmin gene and fms-related tyrosine kinase 3 gene, multivariate survival analysis showed that the NOS3 894 G>T polymorphism appeared to be a predicting factor for OS (P = 0.014; hazard ratio = 1.856). However, no significant associations between the NOS3 894 G>T polymorphism and relapse-free survival and relapse in patients with AML were observed. Gene expression levels were significantly higher in patients with the GG genotype than in patients with the GT and TT genotypes (P = 0.033). The findings suggest that the NOS3 894 G>T variant may be a biomarker for the prediction of OS in Chinese patients with AML.

Homoharringtonine/omacetaxine mepesuccinate: the long and winding road to food and drug administration approval

Homoharringtonine/omacetaxine is a unique agent with a long history of research development. It has been recently approved by the Food and Drug Administration for the treatment of chronic myeloid leukemia after failure of 2 or more tyrosine kinase inhibitors. Research with this agent has spanned over 40 years, with many instructive lessons to cancer research, which are summarized in this review.

Integrative analysis of prognostic factors in Chinese core binding factor leukemia

The characteristics of core binding factor (CBF) leukemia appear to differ between Chinese and Caucasian patients. In this study, we analyzed the biological and clinical characteristics of 76 Chinese CBF leukemia patients out of 425 newly diagnosed acute myeloid leukemia (AML) patients. The frequency of CBF AML was 17.9%. Patients harboring t(8;21) were predominant in CBF AML. The incidence of c-kit mutation in CBF AML was 28.9%. The N822K mutation appeared to be more prevalent in Chinese CBF AML patients. Multivariate analysis showed that c-kit mutation and high white blood cell count could negatively impact overall survival (OS) (HR=2.74 and 6.24, P=0.007 and 0.022, respectively) but did not affect relapse-free survival (RFS). Kaplan-Meier analysis showed a significant difference in both OS and RFS between wild-type and mutated c-kit patients. Although we had included recently reported prognostic indicators in our analysis, our results demonstrated that only c-kit mutation and high white blood cell count had prognostic impact on Chinese CBF AML patients.

Celastrol and an EGCG pro-drug exhibit potent chemosensitizing activity in human leukemia cells

Chemotherapy remains the staple of treatment for many types of leukemia. Despite the positive impact on extending overall survival in patients with hematological malignancies, new treatment strategies are needed to reduce the nonspecific toxicity and improve the efficacy of treatment. Celastrol, derived from the 'Thunder God Vine' and Pro-EGCG, a pre-drug version of green tea polyphenol EGCG have shown potent biological activity in vitro and in vivo. Whether these natural products augment the efficacy of conventional chemotherapy in the treatment of leukemia cells has yet to be demonstrated. Here we demonstrate that these natural products could sensitize the effect of chemotherapy in both K-562 and Jurkat T human leukemia cells. Accordingly, this potent biological activity was associated with increased levels of leukemia cell killing, caspase 3 activation, and poly(ADP-ribose) polymerase cleavage. Furthermore, the higher levels of apoptotic indices were associated with decreased levels of Bcr-Abl oncoprotein in K-562 cells. Taken together, our findings present a compelling rationale for the development of combination strategies using natural products in the treatment of hematological malignancies.