Dose-reduced combination of mitoxantrone, etoposide, and cytarabine (miniMEC) for relapsed and refractory acute leukemia

Magnetically modified-mitoxantrone mesoporous organosilica drugs: an emergent multimodal nanochemotherapy for breast cancer

BACKGROUND

Chemotherapy, the mainstay treatment for metastatic cancer, presents serious side effects due to off-target exposure. In addition to the negative impact on patients' quality of life, side effects limit the dose that can be administered and thus the efficacy of the drug. Encapsulation of chemotherapeutic drugs in nanocarriers is a promising strategy to mitigate these issues. However, avoiding premature drug release from the nanocarriers and selectively targeting the tumour remains a challenge.

RESULTS

In this study, we present a pioneering method for drug integration into nanoparticles known as mesoporous organosilica drugs (MODs), a distinctive variant of periodic mesoporous organosilica nanoparticles (PMOs) in which the drug is an inherent component of the silica nanoparticle structure. This groundbreaking approach involves the chemical modification of drugs to produce bis-organosilane prodrugs, which act as silica precursors for MOD synthesis. Mitoxantrone (MTO), a drug used to treat metastatic breast cancer, was selected for the development of MTO@MOD nanomedicines, which demonstrated a significant reduction in breast cancer cell viability. Several MODs with different amounts of MTO were synthesised and found to be efficient nanoplatforms for the sustained delivery of MTO after biodegradation. In addition, Fe3O4 NPs were incorporated into the MODs to generate magnetic MODs to actively target the tumour and further enhance drug efficacy. Importantly, magnetic MTO@MODs underwent a Fenton reaction, which increased cancer cell death twofold compared to non-magnetic MODs.

CONCLUSIONS

A new PMO-based material, MOD nanomedicines, was synthesised using the chemotherapeutic drug MTO as a silica precursor. MTO@MOD nanomedicines demonstrated their efficacy in significantly reducing the viability of breast cancer cells. In addition, we incorporated Fe3O4 into MODs to generate magnetic MODs for active tumour targeting and enhanced drug efficacy by ROS generation. These findings pave the way for the designing of silica-based multitherapeutic nanomedicines for cancer treatment with improved drug delivery, reduced side effects and enhanced efficacy.

Effect of cumulative daunorubicin dose on cardiotoxicity after allogeneic stem cell transplantation

Cardiotoxicity after allogeneic stem cell transplantation (SCT) is associated with a high rate of mortality and worsening quality of life. The relation between daunorubicin dose and post- allogeneic stem cell transplantation (SCT) cardiotoxicity remains unclear. We retrospectively evaluated 171 patients with acute myeloid leukemia (AML) who underwent their first allogeneic SCT at our institution between 2005 and 2021. High-dose daunorubicin (50 mg/m²/day for 5 days) and cytarabine were usually used as induction therapy for AML. The median cumulative daunorubicin dose was 310 mg/m² (range, 0-950 mg/m²), and 43 patients received two courses of induction therapy with high-dose daunorubicin (daunorubicin doses of ≥500 mg/m²). Cardiotoxicity developed in 12 patients, and the cumulative incidence at 2 years after SCT was 7.1%. Univariable analysis revealed that female sex, left ventricular ejection fraction (LVEF) of < 60% before SCT, and daunorubicin doses of ≥ 500 mg/m² were associated with cardiotoxicity. Multivariable analysis showed that a daunorubicin dose of ≥ 500 mg/m² was an independent risk factor for cardiotoxicity. LVEF decline during the study was observed with an increase in the daunorubicin dose, and only a daunorubicin dose of ≥ 500 mg/m2 was associated with a pre-SCT decreased LVEF. Second induction therapy with high-dose daunorubicin is a risk factor for cardiotoxicity after SCT. This should be taken into consideration when determining reinduction therapies for SCT-eligible patients with relapsed or refractory AML.

Successful treatment with gilteritinib for isolated extramedullary relapse of acute myeloid leukemia with FLT3-ITD mutation after allogeneic stem cell transplantation

Acute myeloid leukemia (AML) harboring Fms-like tyrosine kinase 3 (FLT3) internal tandem duplication (ITD) mutation is associated with shorter remission and higher relapse risk. Several FLT3 inhibitors have been used in clinical trials, but their efficacy in extramedullary disease remains unclear. In the present case, a 56-year-old man was diagnosed with FLT3-ITD mutated AML. Due to bone marrow relapse during consolidation therapy, he underwent salvage therapy and a myeloablative conditioning regimen, followed by peripheral blood stem cell transplantation (PBSCT) from a HLA-matched related donor. Acute graft-versus-host disease (GVHD) did not develop, and complete donor chimerism was confirmed on days 27 and 96 after PBSCT. On day 180, he experienced extensive chronic GVHD and had several subcutaneous tumors in his body, which were diagnosed as myeloid sarcoma by pathological examination. We considered this to be a case of isolated extramedullary relapse, as his bone marrow had maintained complete donor chimerism. Treatment with etoposide and ranimustine produced no effect, and tumor progression continued. We started administration of gilteritinib, a FLT3/AXL inhibitor, after identifying the FLT3-ITD mutation in the tumor. Subsequently, there has been a remarkable regression of the tumors. Gilteritinib can be effective in isolated extramedullary relapse after allogeneic stem cell transplantation.

Study on the precise mechanism of Mitoxantrone-induced Jurkat cell apoptosis using surface enhanced Raman scattering

Mitoxantrone (MTX), one representative of anthraquinone ring anticancer drugs, reveals excellent anticancer effects in acute leukemia. Though current studies have shown that MTX-induced acute leukemia cell apoptosis is implemented by inserting into DNA, and then leading to DNA breakage and the subsequent transcription termination, but the specific location information of MTX embedded in DNA remains unknown. In this study, combining surface enhanced Raman scattering (SERS) and principal component analysis (PCA), we achieve the biochemical changes of MTX-induced Jurkat cell apoptosis and the location information of MTX embedded in DNA. In contrast, we also present the corresponding result of Daunorubicin (DNR)-induced Jurkat cell apoptosis. It is found that the location of MTX embedded in DNA of Jurkat cell is different from DNR, in which the action site of MTX is mainly implemented by blocking and destroying AT base pairs while DNR is performed by embedding and destroying GC base pairs and then the base A. Clearly, this achieved information is very useful for the designing and modification of anthraquinone ring anticancer drugs.