Therapy-related acute myeloid leukemia in patients with lymphoma: A report of four cases and review of the literature

Adult rhabdomyosarcoma combined with acute myeloid leukemia: A case report

BACKGROUND

Rhabdomyosarcoma is a tumor of mesenchymal origin. Secondary leukemia is a complication of previous transformation to other hematologic disorders or is a treatment-related acute myeloid leukemia secondary to cytotoxic chemotherapy or radiation therapy for other malignancies.

CASE SUMMARY

We present the case of a 36-year-old female patient who was diagnosed with rhabdomyosarcoma and acute myeloid leukemia. Further disease progression was observed after multiline chemotherapy. Eventually, the patient suffered cerebral hemorrhage, which resulted in death.

CONCLUSION

The incidence of rhabdomyosarcoma in adults is extremely low, and secondary leukemia caused by rhabdomyosarcoma is even rarer. Secondary leukemia has a very poor prognosis and a low overall survival rate.

Risk and outcome of acute myeloid leukaemia among survivors of primary diffuse large B-cell lymphoma: a retrospective observational study based on SEER database

OBJECTIVES

Survivors of diffuse large B-cell lymphoma (DLBCL) are at an increased risk of developing second primary malignancies. However, the risk of secondary acute myeloid leukaemia (sAML) has not been previously described in detail, and the outcomes of patients with sAML are also undiscovered compared with their de novo counterparts (de novo acute myeloid leukaemia, dnAML).

DESIGN

This study is a retrospective database study.

SETTING AND PARTICIPANTS

A total of 70 280 patients with primary DLBCL, diagnosed between 2000 and 2016, were identified from the Surveillance, Epidemiology, and End Results (SEER) database. Another cohort with dnAML matching with sAML was also obtained from SEER database.

RESULTS

The standardised incidence ratio was 6.23 (95% CI: 5.50 to 7.03) for sAML among survivors of DLBCL. The estimated cumulative incidence of sAML was 0.61% 15 years after the diagnosis of DLBCL. Patients aged 60-74 years were more likely to have sAML than those <60 years (subdistribution HR (sHR)=1.417; 95% CI: 1.087 to 1.850), whereas patients aged ≥75 years were less likely to have sAML (sHR=0.648; 95% CI: 0.452 to 0.930). Patients with advanced-stage DLBCL were more prone to sAML than those with early-stage disease (sHR=1.307; 95% CI: 1.012 to 1.690). There was a significant difference of survival between patients with dnAML and those with sAML (HR=1.25; 95% CI: 1.01 to 1.53).

CONCLUSIONS

The risk of developing sAML after DLBCL is substantial. Patients aged 60-74 years and with advanced-stage are more prone to sAML. And, compared with their dnAML counterparts, patients with sAML have a worse prognosis.

Tumor necrosis factor receptor 2 may promote the proliferation and drug resistance of Kapras299 and L428 lymphoma cells via the AKT and WNT/β-catenin signaling pathways

Circulating soluble tumor necrosis factor receptor 2 (sTNFR2) has been associated with a relatively poor prognosis in various types of lymphoma. However, the specific role of TNFR2 expression in lymphoma cells remains uncharacterized. In the present study, TNFR2 expression was quantified in the Hodgkin lymphoma cell line, L428, and the anaplastic large-cell lymphoma cell line, Karpas299, using RT-PCR and western blot analyses. Karpas299 cells exhibited higher TNFR2 expression than L428 cells. Proliferation and drug resistance experiments demonstrated that Karpas299 cells also possessed a greater proliferative ability and resistance to adriamycin (ADM) than L428 cells, with 50% inhibitory concentrations (IC₅₀) of 1.423±0.24 µmol/l for Karpas299 cells, compared with 0.728±0.15 µmol/l for L428 cells (P<0.05). The knockdown of TNFR2 in Karpas299 cells significantly reduced their proliferative ability; when treated with ADM, the cell inhibition rate increased from 49.34±5.42% to 74.13±6.81% (P<0.05). The upregulation of TNFR2 in L428 cells significantly increased their proliferative ability; when treated with ADM, the cell inhibition rate decreased from 47.03±5.25% to 28.71±4.90% (P<0.05). Investigation of the underlying molecular mechanism indicated that the upregulation of TNFR2 expression in L428 cells increased the expression of β-catenin and the phosphorylation of AKT. In L428 cells overexpressing TNFR2, the β-catenin blocker, DKK1, or the AKT inhibitor, LY294002, abrogated the increase in proliferation induced by TNFR2 and increased cell inhibition rate upon treatment with ADM. In summary, the present study demonstrated that TNFR2 promoted the proliferative and drug resistance abilities of lymphoma cells via the AKT and WNT/β-catenin signaling pathways. This may provide the experimental basis for the further study of TNFR2 activity in lymphoma cells and warrant its investigation as a therapeutic target for lymphoma.

Therapy-related acute myeloid leukemia and myelodysplastic syndrome after hematopoietic cell transplantation for lymphoma

Therapy-related acute myeloid leukemia and myelodysplastic syndrome (t-AML/MDS) represent severe late effects in patients receiving hematopoietic cell transplantation (HCT) for lymphoma. The choice between high-dose therapy with autologous HCT and allogeneic HCT with reduced-intensity conditioning remains controversial in patients with relapsed lymphoma. We retrospectively analyzed incidence and risk factors for the development of t-AML/MDS in lymphoma patients treated with autologous or allogeneic HCT. A total of 13 810 lymphoma patients who received autologous (n=9963) or allogeneic (n=3847) HCT between 1985 and 2012 were considered. At a median overall survival (OS) of 52 and 46 months in autologous and allogeneic HCT groups, respectively, lymphoma patients receiving autologous HCT (1.38% at 3 years after autologous HCT) had a significant risk for developing t-AML/MDS compared to allogeneic HCT (0.37% at 3 years after allogeneic HCT, P<0.001). Significant risk factors for the development of t-AML/MDS after autologous and allogeneic HCT were high-stage risk at HCT (P=0.04) or secondary malignancies (P<0.001) and receiving cord blood stem cell (P=0.03) or involved field radiotherapy (P=0.002), respectively. Strategies that carefully select lymphoma patients for autologous HCT, by excluding lymphoma patients with high-stage risk at HCT, may allow the identification of individual lymphoma patients at particular high risk for t-AML/MDS.

A mechanism for 1,4-Benzoquinone-induced genotoxicity

Benzene is a common environmental toxin and its metabolite, 1-4-Benzoquinone (BQ) causes hematopoietic cancers like myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). BQ has not been comprehensively assessed for its impact on genome maintenance, limiting our understanding of the true health risks associated with benzene exposure and our ability to identify people with increased sensitivity to this genotoxin. Here we analyze the impact BQ exposure has on wild type and DNA repair-defective mouse embryonic stem (ES) cells and wild type human cells. We find that double strand break (DSB) repair and replication fork maintenance pathways including homologous recombination (HR) and Fanconi anemia (FA) suppress BQ toxicity. BQ-induced damage efficiently stalls replication forks, yet poorly induces ATR/DNA-PKCS responses. Furthermore, the pattern of BQ-induced γH2AX and 53BP1foci is consistent with the formation of poly(ADP-ribose) polymerase 1 (PARP1)-stabilized regressed replication forks. At a biochemical level, BQ inhibited topoisomerase 1 (topo1)-mediated DNA ligation and nicking in vitro; thus providing mechanism for the cellular phenotype. These data are consistent with a model that proposes BQ interferes with type I topoisomerase's ability to maintain replication fork restart and progression leading to chromosomal instability that has the potential to cause hematopoietic cancers like MDS and AML.