Use of decitabine for patients with refractory or relapsed acute myeloid leukemia: a systematic review and meta-analysis

Decitabine as epigenetic priming with CLAG induce improved outcome of relapsed or refractory acute myeloid leukemia in children

BACKGROUND

Decitabine (DAC), a DNA methyltransferase inhibitor, has shown efficacy combined with chemotherapy for relapsed or refractory (R/R) acute myeloid leukemia (AML) in adults, but less is known about its efficacy in children. Accordingly, we conducted a study which involved a priming regimen consisting of DAC with cladribine, cytarabine, and granulocyte-stimulating factor (DAC-CLAG) and compared the efficacy and safety of this regimen with CLAG alone.

METHODS

A total of 39 R/R AML children who received the CLAG or DAC-CLAG regimen in Shanghai Children's Hospital were retrospectively enrolled in this non-randomized study. These regimens were studied sequentially over time. Twenty-two patients received CLAG from 2015, while 17 patients were administered epigenetic priming with DAC before CLAG from 2020. Patients were subsequently bridged to stem cell transplantation (SCT) or consolidation chemotherapy. Complete remission (CR) and adverse effects were analyzed by Fisher's exact test, and survival was analyzed by the Kaplan-Meier method.

RESULTS

DAC-CLAG conferred a numerically higher CR compared to CLAG (70.59% vs 63.64%; P = 0.740). High CR rates occurred in patients with good cytogenetics (P = 0.029) and prior induction without cladribine (P = 0.099). The 1-year event-free survival (EFS) was 64.71% ± 11.59% and 63.31% ± 10.35% in the DAC-CLAG and CLAG group (P = 0.595), and 1-year overall survival (OS) was 81.45% ± 9.72% and 77.01% ± 9.04%, respectively (P = 0.265). The 1-year OS and EFS after SCT were higher in the DAC-CLAG than in the CLAG cohort (100% vs 92.31% ± 7.39%, P = 0.072; 92.31% ± 7.39% vs 85.71% ± 9.35%, P = 0.158). Univariate analysis revealed that a good prognosis included good cytogenetics (P = 0.002), non-complex karyotype (P = 0.056), CR on reinduction (P < 0.0001), and bridging to SCT (P = 0.0007). Use of a hypomethylating agent (P = 0.049) and bridging to SCT (P = 0.011) were independent prognostic factors. Grade 3/4 hematologic toxicity and infection were the main adverse events.

CONCLUSIONS

DAC prior to the CLAG regimen improved remission in pediatric R/R AML, and was feasible and well tolerated. CLAG ± DAC as a salvage therapy prior to SCT induced improved survival.

An overview of arsenic trioxide-involved combined treatment algorithms for leukemia: basic concepts and clinical implications

Arsenic trioxide is a first-line treatment drug for acute promyelocytic leukemia, which is also effective for other kinds of leukemia. Its side effects, however, limit its clinical application, especially for patients with complex leukemia symptoms. Combination therapy can effectively alleviate these problems. This review summarizes the research progress on the combination of arsenic trioxide with anticancer drugs, vitamin and vitamin analogs, plant products, and other kinds of drugs in the treatment of leukemia. Additionally, the new progress in arsenic trioxide-induced cardiotoxicity was summarized. This review aims to provide new insights for the rational clinical application of arsenic trioxide.

Decitabine combined with RDHAP regimen in relapsed/refractory diffuse large B cell lymphoma

BACKGROUND

There is an urgent need for effective treatment of patients with relapsed/refractory diffuse large B-cell lymphoma (R/R-DLBCL). This trial investigated the efficacy of decitabine in combination with rituximab, cisplatin, cytarabine, dexamethasone (RDHAP) in R/R-DLBCL.

METHODS

56 patients were divided into two groups (decitabine-RDHAP group. n = 35; RDHAP group, n = 21). The primary endpoints were the overall response rate (ORR) and duration of remission (DOR). Secondary objectives were toxicity, progression-free survival (PFS), and overall survival (OS).

RESULTS

The ORR was 40% and 33% for decitabine-RDHAP and RDHAP groups, respectively, with no difference between the groups. The DOR for the decitabine-RDHAP regimen was higher than that for the RDHAP regimen (p = 0.044). After a median follow-up of 12.0 months, the median PFS and OS were 7.0 and 17.0 months for in the decitabine-RDHAP group and 5.0 and 9.0 months in the RDHAP group with no significant differences between the two groups (p = 0.47, 0.17). The incidence of adverse events was not significantly different between groups.

CONCLUSION

The decitabine-RDHAP regimen is effective and well tolerated, and is a promising salvage regimen for R/R-DLBCL.

Efficacy of azacitidine in preventing relapse after hematopoietic stem cell transplantation for advanced myeloid malignancies: a systematic review and meta-analysis

BACKGROUND

Relapse is the leading cause of death from myeloid malignancies after allogeneic hematopoietic stem cell transplantation (HSCT). Azacitidine has gained attention in recent years in the prophylaxis of relapsed refractory hematologic malignancies. This study evaluated the efficacy of AZA in preventing relapse after HSCT in patients with myeloid malignancies.

METHODS

A systematic review and meta-analysis of all available cohort studies were performed regarding the application of AZA for prophylaxis of relapse after HSCT for advanced MDS and AML. Databases were searched for relevant studies. Endpoints included 2-year relapse rate, survival, relapse-related mortality, as well as the incidence of graft-versus-host disease (GVHD).

RESULTS

A total of 444 patients from 13 studies were included in this analysis. The pooled estimate of the cumulative incidence of relapse after two years in enrolled patients was 25% (95% confidence interval [CI], 18%-33%). The pooled estimates of 2-year survival probabilities were 65% (95% CI, 50%-79%). The pooled cumulative incidence of relapse-related mortality was 28% (95% CI, 22%-34%). The pooled estimated incidence of acute and chronic GVHD, respectively, were 28% (95% CI, 22%-34%) and 38% (95% CI, 27%-49%).

CONCLUSION

AZA administration is efficacious for relapse prevention after HSCT in myeloid malignancies.

Short communication: TNF-α and IGF-1 regulates epigenetic mechanisms of HDAC2 and HDAC10

Vascular restenosis often presents as a consequence of injury to the vessel wall, resulting from stenting and other interventional procedures. Such injury to the arteries induces proliferation of Vascular Smooth Muscle Cells (VSMCs), resulting in cellular hyperplasia and restenosis. We and others have previously reported de-novo production of different cytokines and growth factors such as Tumor Necrosis Factor Alpha (TNF-α) and Insulin like Growth Factor 1 (IGF-1), after vascular injury. As complex as it is, the profuse proliferation of VSMCs appears to be occurring due to several induced factors which initiate molecular mechanisms and exacerbate disease conditions. In many pathological events, the deleterious effects of TNF-α and IGF-1 in initiating disease mechanisms was reported. In the present work, we explored whether TNF-α and IGF-1 can regulate epigenetic mechanisms that promote proliferation of VSMCs. We investigated the mechanistic roles of proteins which can structurally interact with DNMT1 and initiate cellular pathways that promote proliferation of VSMCs. Our findings here, identify a novel molecular mechanism that is initiated by TNF-α and IGF-1. It was previously reported that DNMT1 expression is directly induced by TNF-α and IGF-1 treatment and increased/induced expression of DNMT1 causes silencing of genes that are essential to maintaining cellular homeostasis such as the tumor suppressor genes. We have earlier reported that TNF-α and IGF-1 treatment elevates DNMT1 expression in VSMCs and causes increased VSMC proliferation. However, the molecular mechanisms involved were not fully deciphered. Interestingly, in the present study we found that TNF-α and IGF-1 treatment failed to elevate DNMT1 expression levels in absence of HDAC2 and HDAC10. Also, while HDAC2 expression was not affected by HDAC10 knockdown, HDAC2 is essentially required for HDAC10 expression. Further, in TNF-α and IGF-1 induced epigenetic signaling mechanism, the expression of two important proteins EZH2 and PCNA seem to be regulated in an HDAC2-HDAC10 dependent manner. Our results show an inter-dependence of epigenetic mediators in inducing proliferation in VSMCs. To our knowledge, this is the first report that shows HDAC2 dependent expression of HDAC10, and suggests a novel mechanistic link between DNMT1, HDAC10 and HDAC2 that regulates EZH2 and PCNA to enhance cell proliferation of VSMCs which is the underlying cause for neointimal hyperplasia and restenosis.

A guideline for the outpatient management of glycaemic control in people with cancer

Individuals with cancer are at increased risk of developing new-onset diabetes mellitus and hyperglycaemia, and an estimated 20% of people with cancer already have an underlying diagnosis of diabetes mellitus. People with both cancer and diabetes may have an increased risk of toxicities, hospital admissions and morbidity, with hyperglycaemia potentially attenuating the efficacy of chemotherapy often secondary to dose reductions and early cessation. Numerous studies have demonstrated that hyperglycaemia is prognostic of worse overall survival and risk of cancer recurrence. These guidelines aim to provide the oncology/haemato-oncology and diabetes multidisciplinary teams with the tools to manage people with diabetes commencing anti-cancer/glucocorticoid therapy, as well as identifying individuals without a known diagnosis of diabetes who are at risk of developing hyperglycaemia and new-onset diabetes.

A Retrospective Observation of Treatment Outcomes Using Decitabine-Combined Standard Conditioning Regimens Before Transplantation in Patients With Relapsed or Refractory Acute Myeloid Leukemia

Hypomethylating agents, decitabine (DAC) and azacitidine, can act as prophylactic and pre-emptive approaches after allogeneic hematopoietic stem cell transplantation (allo-HSCT) and a non-intensive bridging approach before allo-HSCT. However, they are rarely used as a part of conditioning regimens in patients with relapsed or refractory acute myeloid leukemia (AML). This retrospectively study included a total of 65 patients (median, 37; range, 13–63) with relapsed or refractory AML who were treated by allo-HSCT after myeloablative conditioning regimens without or with DAC (high-dose DAC schedule, 75 mg/m² on day −9 and 50 mg/m² on day −8; low-dose DAC schedule, 25 mg/m²/day on day −10 to −8). DAC exerted no impact on hematopoietic reconstitution. However, patients who were treated with the high-dose DAC schedule had significantly higher incidence of overall survival (OS, 50.0%) and leukemia-free survival (LFS, 35.0%), and lower incidence of relapse (41.1%) and grade II–IV acute graft versus host disease (aGVHD, 10.0%) at 3 years, when compared with those treated with standard conditioning regimens or with the low-dose DAC schedule. In conclusion, high-dose DAC combined with standard conditioning regimens before allo-HSCT is feasible and efficient and might improve outcomes of patients with relapsed or refractory AML, which provides a potential approach to treat these patients.

Synergistic inhibitory effect of Smo inhibitor jervine and its combination with decitabine can target Hedgehog signaling pathway to inhibit myelodysplastic syndrome cell line

OBJECTIVE

Hypomethylating agents (HMAs) have been reported to target the Sonic Hedgehog (Shh) signaling pathway in myelodysplastic syndrome (MDS). However, the synergistic inhibitory effect of Smo inhibitor jervine and its combination with decitabine in MUTZ-1 cell lines remains lacking.

METHODS

We used a CCK-8 assay to detect the in-vitro proliferation rate of MUTZ-1 cell lines. Besides, the Annexin V-FITC/PI double staining flow cytometry was utilized to detect the apoptosis rate and cell cycle changes. The expression levels of mRNA were quantified by using qRT-PCR, and the western blot was employed to detect the expression of proteins.

RESULTS

We found that the single-agent jervine or decitabine can significantly inhibit the proliferation rate of MUTZ-1 cell lines, and this inhibitory effect is time-dependent and concentration-dependent. The combined intervention of the jervine and decitabine can more significantly inhibit cell proliferation, induce cell apoptosis, and block the G1 phase of the cell cycle. The combined intervention of the two drugs significantly reduced Smo and G1i-1 mRNA expression in MUTZ-1 cells. Furthermore, after combining both of the drug treatments, the proteins levels of Smo, G1i-1, PI3K, p-AKT, Bcl2, and Cyclin Dl were significantly downregulated, and Caspase-3 is upregulated, indicating that jervine with its combination of decitabine might be effective for controlling the proliferation, apoptosis, and cell cycle.

CONCLUSION

The Smo inhibitor jervine and its combination with decitabine have a synergistic effect on the proliferation, cell cycle, and apoptosis of MUTZ-1 cells, and its mechanism may be achieved by interfering with the Shh signaling pathway.

Identification by TCGA database search of five genes that are aberrantly expressed and involved in hepatocellular carcinoma potentially via DNA methylation changes

BACKGROUND

Various treatments for hepatocellular carcinoma (HCC) are utilized in clinical practice; however, the prognosis is still poor on account of high recurrence rates. DNA methylation levels of CpG islands around promoters (promoter CpGis) inversely regulate gene expression and closely involved in carcinogenesis. As a new strategy, several chemicals globally inhibiting DNA methylation have been developed aiming at reducing DNA methylation levels and maintaining the expression of tumor suppressor genes. On the other hand, since these drugs nonspecifically modify DNA methylation, they can cause serious adverse effects. In order to ameliorate the methods by targeting specific CpGs, information of cancer-related genes that are regulated by DNA methylation is required.

METHODS

We searched candidate genes whose expressions were regulated by DNA methylation of promoter CpGi and which are involved in HCC cases. To do so, we first identified genes whose expression were changed in HCC by comparing gene expressions of 371 HCC tissues and 41 non-tumor tissues using the Cancer Genome Atlas (TCGA) database. The genes were further selected for poor prognosis by log-rank test of Kaplan-Meier plot and for cancer relevance by Pubmed search. Expression profiles of upregulated genes in HCC tissues were assessed by Gene Ontology (GO) analysis. Finally, using DNA methylation data of TCGA database, we selected genes whose promoter DNA methylation levels were inversely correlated with gene expression.

RESULTS

We found 115 genes which were significantly up- or downregulated in HCC tissues and were associated with poor prognosis and cancer relevance. The upregulated genes were significantly enriched in cell division, cell cycle, and cell proliferation. Among the upregulated genes in HCC, we identified hypomethylation of CpGis around promoters of FANCB, KIF15, KIF4A, ERCC6L, and UBE2C. In addition, TCGA data showed that the tumor suppressor gene P16 is unexpectedly overexpressed in many types of cancers.

CONCLUSIONS

We identified five candidate genes whose expressions were regulated by DNA methylation of promoter CpGi and associate with cancer cases and poor prognosis in HCC. Modification of site-specific DNA methylation of these genes enables a different approach for HCC treatment with higher selectivity and lower adverse effects.