Research on different compound combinations of Realgar-Indigo naturalis formula to reverse acute promyelocytic leukemia arsenic resistance by regulating autophagy through mTOR pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: In China, the Chinese patent drug Realgar-Indigo naturalis Formula (RIF) is utilized for the therapy of acute promyelocytic leukemia (APL). Comprising four traditional Chinese herb-Realgar, Indigo naturalis, Salvia miltiorrhiza, and Pseudostellaria heterophylla-it notably includes tetra-arsenic tetra-sulfide, indirubin, tanshinone IIa, and total saponins of Radix Pseudostellariae as its primary active components. Due to its arsenic content, RIF distinctly contributes to the therapy for APL. However, the challenge of arsenic resistance in APL patients complicates the clinical use of arsenic agents. Interestingly, RIF demonstrates a high remission rate in APL patients, suggesting that its efficacy is not significantly compromised by arsenic resistance. Yet, the current state of research on RIF's ability to reverse arsenic resistance remains unclear. AIM OF THE STUDY: To investigate the mechanism of different combinations of the compound of RIF in reversing arsenic resistance in APL. MATERIALS AND METHODS: The present study utilized the arsenic-resistant HL60-PMLA216V-RARα cell line to investigate the effects of various RIF compounds, namely tetra-arsenic tetra-sulfide (A), indirubin (I), tanshinone IIa (T), and total saponins of Radix Pseudostellariae (S). The assessment of cell viability, observation of cell morphology, and evaluation of cell apoptosis were performed. Furthermore, the mitochondrial membrane potential, changes in the levels of PMLA216V-RARα, apoptosis-related factors, and the PI3K/AKT/mTOR pathway were examined, along with autophagy in all experimental groups. Meanwhile, we observed the changes about autophagy after blocking the PI3K or mTOR pathway. RESULTS: Tanshinone IIa, indirubin and total saponins of Radix Pseudostellariae could enhance the effect of tetra-arsenic tetra-sulfide down-regulating PMLA216V-RARα, and the mechanism was suggested to be related to inhibiting mTOR pathway to activate autophagy. CONCLUSIONS: We illustrated that the synergistic effect of different compound combinations of RIF can regulate autophagy through the mTOR pathway, enhance cell apoptosis, and degrade arsenic-resistant PMLA216V-RARα.

A case report of acute promyelocytic leukemia with mycosis fungoides.

RATIONALE: Acute promyelocytic leukaemia (APL) is a rare subtype of acute myelogenous leukaemia. With advances in treatment regimens, namely, introduction of all-trans-retinoicacid, outcomes have drastically improved, its side effects should not be ignored. Mycosis fungoides is one of the side effects of all-trans-retinoicacid treatment, but it may also be a clinical manifestation before disease progression. However, it rarely appears and is easily overlooked. This leads to being easily misled during the treatment process, affecting the treatment plan, and resulting in adverse consequences. Therefore, early identification and judgment can not only provide appropriate treatment options, but also prevent and treat further disease progression. PATIENT CONCERNS: The patient was hospitalized for pancytopaenia. After completing the examination, the patient was finally diagnosed with acute promyelocytic leukaemia (acute myelogenous leukaemia-M3). We administered tretinoin and arsenous acid. Evaluation of the treatment effect on the 7th day after chemotherapy showed that the bone marrow morphology showed complete remission. After the second course of chemotherapy, the patient developed red miliary macular papules, which gradually worsened. After completing relevant inspections, Considering that the cases was complicated with skin mycosis fungoides, the patient was treated with budesonide ointment and methylprednisolone as chemotherapy. DIAGNOSES: Upon examination, the patient was initially diagnosed with acute promyelocytic leukaemia. Evaluation of the treatment effect on the 7th day after chemotherapy showed that the bone marrow morphology showed complete remission. After the second course of chemotherapy, we discovered the patient was diagnosed with skin mycosis fungoides. INTERVENTIONS: Systemic chemotherapy is first given when a patient was diagnosed with acute promyelocytic leukaemia. After the patient happened skin mycosis fungoides, We have adjusted the treatment plan and supplemented it with other treatment plans based on the original chemotherapy, After 2 months of treatment, his condition gradually improved. OUTCOMES: All-trans-retinoicacid in the treatment of APL must be given attention because mycosis fungoides should not only be distinguished from infectious diseases but also be further assessed with regard to disease progression and metastasis. LESSONS: Acute promyelocytic leukemia needs to be treated with arsenic trioxide. All-trans-retinoicacid in the treatment of APL must be given attention mycosis fungoides. Early diagnosis can guide accurate treatment, which is of great help in alleviating the pain of patients and improving the cure rate.

Acute kidney injury in acute promyelocytic leukemia: a possible adverse effect of high dose arsenic trioxide in obese patients.

Arsenic trioxide (ATO)-based regimens are standard in acute promyelocytic leukemia (APL). ATO-related nephrotoxicity has not been reported. We reviewed APL patients treated with ATO to identify cases of acute kidney injury (AKI). Clinically significant cases were characterized. Multivariate analysis was performed to identify predictors of idiopathic, clinically significant AKI. One hundred and eight patients were included. ATO dose was 0.15 mg/kg/day using actual body weight with no dose cap. Thirty-one (28.7%) AKI cases were identified, 10 (32.3%) clinically significant. Six were idiopathic; five required dialysis. The proportion with significant, idiopathic AKI was 15.8% in patients receiving >15mg ATO versus 0% in those receiving ≤15mg (p = 0.001). On multivariate analysis, only ATO dose was a significant predictor of clinically significant AKI (odds ratio of 1.91, 95%CI, 1.19-3.07, p = 0.007). High-dose ATO may be associated with significant nephrotoxicity. We recommend that ATO dose be capped at 15 mg to minimize toxicity for this curable disease.

Arsenic trioxide: applications, mechanisms of action, toxicity and rescue strategies to date.

Arsenical medicine has obtained its status in traditional Chinese medicine for more than 2,000 years. In the 1970s, arsenic trioxide was identified to have high efficacy and potency for the treatment of acute promyelocytic leukemia, which promoted many studies on the therapeutic effects of arsenic trioxide. Currently, arsenic trioxide is widely used to treat acute promyelocytic leukemia and various solid tumors through various mechanisms of action in clinical practice; however, it is accompanied by a series of adverse reactions, especially cardiac toxicity. This review presents a comprehensive overview of arsenic trioxide from preclinical and clinical efficacy, potential mechanisms of action, toxicities, and rescue strategies for toxicities to provide guidance or assistance for the clinical application of arsenic trioxide.

Long-term outcome of children with acute promyelocytic leukemia: a randomized study of oral versus intravenous arsenic by SCCLG-APL group.

Realgar-Indigo naturalis formula (RIF), an oral traditional Chinese medicine mainly containing Realgar (As4S4), is highly effective in treating adult acute promyelocytic leukemia (APL). However, the treatment efficacy and safety of RIF have not been verified in pediatric patients. SCCLG-APL group conducted a multicenter randomized non-inferiority trial to determine whether intravenous arsenic trioxide (ATO) can be substituted by oral RIF in treating pediatric APL. Of 176 eligible patients enrolled, 91 and 85 were randomized to ATO and RIF groups, respectively. Patients were treated with the risk-adapted protocol. Induction, consolidation, and 96-week maintenance treatment contained all-trans-retinoic acid and low-intensity chemotherapy, and either ATO or RIF. The primary endpoint was 5-year event-free survival (EFS). The secondary endpoints were adverse events and hospital days. After a median 6-year follow-up, the 5-year EFS was 97.6% in both groups. However, the RIF group had significantly shorter hospital stays and lower incidence of infection and tended to have less cardiac toxicity. All 4 relapses occurred within 1.5 years after completion of maintenance therapy. No long-term arsenic retentions were observed in either group. Substituting oral RIF for ATO maintains treatment efficacy while reducing hospitalization and adverse events in treating pediatric APL patients, which may be a future treatment strategy for APL.

Integrated bioinformatics analysis and network pharmacology to explore the potential mechanism of Patrinia heterophylla Bunge against acute promyelocytic leukemia.

INTRODUCTION: Current treatment with arsenic trioxide and all-trans retinoic acid has greatly improved the therapeutic efficacy and prognosis of acute promyelocytic leukemia (APL), but may cause numerous adverse effects. Patrinia heterophylla Bunge (PHEB), commonly known as "Mu-Tou-Hui" in China, is effective in treating leukemia. However, no studies have reported the use of PHEB for APL treatment. In this study, we aimed to investigate the potential anticancer mechanism of PHEB against APL. METHODS: Public databases were used to search for bioactive compounds in PHEB, their potential targets, differentially expressed genes associated with APL, and therapeutic targets for APL. The core targets and signaling pathways of PHEB against APL were identified by the protein-protein interaction network, Kaplan-Meier curves, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes pathway enrichment, and compound-target-pathway network analysis. Molecular docking was performed to predict the binding activity between the most active compounds and the key targets. RESULTS: Quercetin and 2 other active components of PHEB may exert anti-APL effects through proteoglycans in cancer, estrogen signaling, and acute myeloid leukemia pathways. We also identified 6 core targets of the bioactive compounds of PHEB, including protein tyrosine phosphatase receptor type C, proto-oncogene tyrosine-protein kinase Src, mitogen-activated protein kinase phosphatase 3 (MAPK3), matrix metalloproteinase-9, vascular endothelial growth factor receptor-2, and myeloperoxidase, most of which were validated to improve the 5-year survival of patients. Molecular docking results showed that the active compound bound well to key targets. CONCLUSION: The results not only predict the active ingredients and potential molecular mechanisms of PHEB against APL, but also help to guide further investigation into the anti-APL application of PHEB.

Dissection of scientific compatibility of Chinese medicinal formula Realgar-Indigo naturalis as an effective treatment for promyelocytic leukemia from the perspective of toxicology.

ETHNOPHARMACOLOGICAL RELEVANCE: Realgar-Indigo naturalis formula (RIF), a first-line drug for the treatment of acute promyelocytic leukemia (APL),is also a TCM formula entirely designed based on TCM theories. There have been studies that explain the scientific connotation of the compatibility of RIF from the perspective of pharmacodynamics. However, as one of the arsenic-containing preparations, the safety of realgar is widely concerned, and there has not been systematic studies to explain the scientific connotation of RIF from the perspective of toxicology. AIM OF THIS STUDY: Dissection of scientific compatibility of Chinese medicinal formula Realgar-Indigo naturalis as an effective treatment for promyelocytic leukemia from the perspective of toxicology. MATERIALS AND METHODS: We used normal mice and an APL model to explore (i) the effects of different components on intestinal permeability, (ii) the changes in intestinal flora, and (iii) toxic effects. At the same time, a bionic extraction method was used to study the effects of different components on the dissolution of soluble arsenic in realgar under the acidic environment in the stomach and the alkaline environment in the intestinal tract. RESULTS: Salvia miltiorrhiza Bunge can repair the intestinal mucosal barrier, maintain the homeostasis of intestinal flora, intervene in the dissolution process of realgar, reverse the increase in intestinal permeability and the disturbance of intestinal flora caused by realgar, and reduce toxicity. CONCLUSION: From the perspective of toxicology, we propose new insights into the definition of the roles of each component in the RIF formula, namely realgar is the monarch, Indigo naturalis is the minister, Salvia miltiorrhiza Bungeis the assistant.

The application of arsenic trioxide in cancer: An umbrella review of meta-analyses based on randomized controlled trials.

ETHNOPHARMACOLOGICAL RELEVANCE: Processed from natural minerals, arsenic trioxide (ATO) as an ancient Chinese medicine has been used to treat diseases for over 2000 years. And it was applied to treat acute promyelocytic leukemia (APL) since the 1970s in China. Summarizing the clinical evidence of ATO in cancer is conducive to further understanding, development, and promotion of its pharmacological research. AIM OF THE STUDY: It is the first time to comprehensively assess and summarize the evidence of ATO in cancer treatment via umbrella review. MATERIALS AND METHODS: 8 databases in English or Chinese from their inception to February 21, 2023 were searched by two reviewers separately and suitable meta-analyses (MAs) were included in this umbrella review. Their methodological quality and risk of bias were evaluated and data of outcomes was extracted and pooled again. The evidence certainty of pooled results was classified. RESULTS: 17 MAs with 27 outcomes and seven comparisons in three cancers were included in this umbrella review. However, their methodological quality was unsatisfactory with 6 MAs as low quality and 12 MAs as critically low quality. Their shortcomings were mainly focused on protocol, literature selecting, bias risk, small sample study bias, and conflicts of interest or funding. And they were all assessed as high risk in bias. It was suggested that ATO had an advantage in enhancing complete remission rate, event-free survival, and recurrence free survival and decreasing recurrence rate, cutaneous toxicity, hyper leukocyte syndrome, tretinoin syndrome, edema and hepatotoxicity in different comparisons of APL with low or moderate certainty. Besides, compared with transcatheter arterial chemoembolization (TACE) alone, ATO plus TACE also could improve objective response rate, disease control rate, survival rate (0.5, 1, 2, and 3-year) and life quality and reduce the level of alpha fetoprotein in primarily hepatocellular carcinoma with low or moderate certainty. However, no significant results were found in MM. Finally, key findings were as followed. ATO has potential broad-spectrum anticancer effects but the clinical transformation is rarely achieved. Route of administration may affect the antitumor effects of ATO. ATO can act synergistically in combination with a variety of antitumor therapies. The safety and drug resistance of ATO should be paid more attention to. CONCLUSIONS: ATO may be a promising drug in anticancer treatment although earlier RCTs have dragged down the level of evidence. However, high-quality clinical trials are expected to explore its broad-spectrum anticancer effects, wide application, appropriate route of administration, and compound dosage form.

Hyperthermia promotes degradation of the acute promyelocytic leukemia driver oncoprotein ZBTB16/RARα.

The acute promyelocytic leukemia (APL) driver ZBTB16/RARα is generated by the t(11;17) (q23;q21) chromosomal translocation, which is resistant to combined treatment of all-trans retinoic acid (ATRA) and arsenic trioxide (ATO) or conventional chemotherapy, resulting in extremely low survival rates. In the current study, we investigated the effects of hyperthermia on the oncogenic fusion ZBTB16/RARα protein to explore a potential therapeutic approach for this variant APL. We showed that Z/R fusion protein expressed in HeLa cells was resistant to ATO, ATRA, and conventional chemotherapeutic agents. However, mild hyperthermia (42 °C) rapidly destabilized the ZBTB16/RARα fusion protein expressed in HeLa, 293T, and OCI-AML3 cells, followed by robust ubiquitination and proteasomal degradation. In contrast, hyperthermia did not affect the normal (i.e., unfused) ZBTB16 and RARα proteins, suggesting a specific thermal sensitivity of the ZBTB16/RARα fusion protein. Importantly, we found that the destabilization of ZBTB16/RARα was the initial step for oncogenic fusion protein degradation by hyperthermia, which could be blocked by deletion of nuclear receptor corepressor (NCoR) binding sites or knockdown of NCoRs. Furthermore, SIAH2 was identified as the E3 ligase participating in hyperthermia-induced ubiquitination of ZBTB16/RARα. In short, these results demonstrate that hyperthermia could effectively destabilize and subsequently degrade the ZBTB16/RARα fusion protein in an NCoR-dependent manner, suggesting a thermal-based therapeutic strategy that may improve the outcome in refractory ZBTB16/RARα-driven APL patients in the clinic.

Tetra-arsenic tetra-sulfide enhances NK-92MI mediated cellular immunotherapy in all-trans retinoic acid-resistant acute promyelocytic leukemia.

Acute promyelocytic leukemia (APL) is liable to induce disseminated intravascular coagulation and has a high early mortality. Although the combination of all-trans retinoic acid (ATRA) and arsenic trioxide (ATO) has significantly improved the complete remission rate, there are still some patients developed drug resistance. Growing evidence suggests that natural killer (NK) cell-mediated immunotherapy as a new treatment can help slow the progression of hematological malignancies. Previous studies also indicated that some tumors exhibited excellent responsiveness to NK cells in vitro. However, many clinical trial results showed that the anti-tumor effect of NK cells infusion alone was not ideal, which may be related to the inactivation of infiltrating NK cells caused by strong immunosuppression in tumor microenvironment, but the specific mechanism remains to be further explored. In the present study, we demonstrated that low doses of tetra-arsenic tetra-sulfide (As4S4) not only enhanced the in vitro killing of NK-92MI against ATRA-resistant APL cells, but also strengthened the growth inhibition of xenografted tumors in APL mouse model. Mechanistically, As4S4 altered the expression of natural killer group 2 member D ligands (NKG2DLs) and cytokines in APL cells, and PD-1 in NK-92MI cells. In addition, database retrieval results further revealed the relationship between the differentially regulated molecules of As4S4 and immune infiltration and its impact on prognosis. In conclusion, our findings confirmed the potential of As4S4 as an adjuvant for NK-92MI in the treatment of ATRA-resistant APL.

Cinobufagin induces acute promyelocytic leukaemia cell apoptosis and PML-RARA degradation in a caspase-dependent manner by inhibiting the ß-catenin signalling pathway.

CONTEXT: Acute promyelocytic leukaemia (APL) is a malignant hematological tumour characterized by the presence of promyelocytic leukaemia-retinoic acid receptor A (PML-RARA) fusion protein. Cinobufagin (CBG) is one of the main effective components of toad venom with antitumor properties. However, only a few reports regarding the CBG treatment of APL are available. OBJECTIVE: We explored the effect and mechanism of action of CBG on NB4 and NB4-R1 cells. MATERIALS AND METHODS: We evaluated the viability of NB4 and NB4-R1 cells treated with 0, 20, 40, and 60 nM CBG for 12, 24, and 48 h. After treatment with CBG for 24 h, Bcl-2 associated X (Bax), B-cell lymphoma 2 (Bcl-2), ß-catenin, cyclin D1, and c-myc expression was detected using western blotting and real-time polymerase chain reaction. Caspase-3 and PML-RARA expression levels were detected using western blotting. RESULTS: CBG inhibited the viability of NB4 and NB4-R1 cells. The IC50 values of NB4 and NB4-R1 cells treated with CBG for 24 h were 45.2 nM and 37.9 nM, respectively. CBG induced NB4 and NB4-R1 cell apoptosis and PML-RARA degradation in a caspase-dependent manner and inhibited the ß-catenin signalling pathway. DISCUSSION AND CONCLUSION: CBG induced NB4 and NB4-R1 cell apoptosis and PML-RARA degradation in a caspase-dependent manner by inhibiting the ß-catenin signalling pathway. This study proposes a novel treatment strategy for patients with APL, particularly those with ATRA-resistant APL.

Realgar (As4S4), a traditional Chinese medicine, induces acute promyelocytic leukemia cell death via the Bcl-2/Bax/Cyt-C/AIF signaling pathway in vitro.

Acute promyelocytic leukemia (APL) is a specific subtype of acute myelogenous leukemia (AML) characterized by the proliferation of abnormal promyelocytes. Realgar, a Chinese medicine containing arsenic, can be taken orally. Traditional Chinese medicine physicians have employed realgar to treat APL for over a thousand years. Therefore, realgar may be a promising candidate for the treatment of APL. Nevertheless, the underlying mechanism behind realgar therapy is largely unclear. The present study aimed to investigate the effect of realgar on cell death in the APL cell line (NB4) in vitro and to elucidate the underlying mechanism. In this study, after APL cells were treated with different concentrations of realgar, the cell survival rate, apoptotic assay, morphological changes, ATP levels and cell cycle arrest were assessed. The expression of Bcl-2, Bax, Cytochrome C (Cyt-C) and apoptosis-inducing factor (AIF) at the mRNA and protein levels were also measured by immunofluorescence, quantitative PCR (qPCR) and Western blotting. We found that realgar could significantly inhibit APL cell proliferation and cell death in a time- and dose-dependent manner. Realgar effectively decreased the ATP levels in APL cells. Realgar also induced APL cell cycle arrest at the S and G2/M phases. Following realgar treatment, the mRNA and protein levels of Bcl-2 were significantly downregulated, whereas the levels of Bax, Cyt-C, and AIF were significantly upregulated. In summary, realgar can induce APL cell death via the Bcl-2/Bax/Cyt-C/AIF signaling pathway, suggesting that realgar may be an effective therapeutic for APL.

Functional association of NR4A3 downregulation with impaired differentiation in myeloid leukemogenesis.

The coincident downregulation of NR4A1 and NR4A3 has been implicated in myeloid leukemogenesis, but it remains unknown how these two genes function in myeloid cells and how their combined downregulation promotes myeloid leukemogenesis. Since NR4A1 abrogation is thought to confer a survival and proliferation advantage to myeloid cells, we hypothesized that downregulation of NR4A3 may have a complementary effect on myeloid cell differentiation. First, we tested the association between differentiation status of leukemic cells and NR4A3 expression using two large clinical datasets from patients with different acute myeloid leukemia (AML) subtypes. The analysis revealed a close association between differentiation status and different subtypes of AML Then, we probed the effects of differentiation-inducing treatments on NR4A3 expression and NR4A3 knockdown on cell differentiation using two myeloid leukemia cell lines. Differentiation-inducing treatments caused upregulation of NR4A3, while NR4A3 knockdown prevented differentiation in both cell lines. The cell culture findings were validated using samples from chronic myeloid leukemia (CML) patients at chronic, accelerated and blastic phases, and in acute promyelocytic leukemia (APL) patients before and after all trans-retinoic acid (ATRA)-based differentiation therapy. Progressive NR4A3 downregulation was coincident with impairments in differentiation in patients during progression to blastic phase of CML, and NR4A3 expression was increased in APL patients treated with ATRA-based differentiating therapy. Together, our findings demonstrate a tight association between impaired differentiation status and NR4A3 downregulation in myeloid leukemias, providing a plausible mechanistic explanation of how myeloid leukemogenesis might occur upon concurrent downregulation of NR4A1 and NR4A3.

The comparison of plasma arsenic concentration and urinary arsenic excretion during treatment with Realgar-Indigo naturalis formula and arsenic trioxide in children with acute promyelocytic leukemia.

Realgar-Indigo naturalis formula (RIF) is a traditional Chinese medicine containing As4S4 and effective in treating acute promyelocytic leukemia (APL). The dose of RIF remains to be determined in pediatric patients. Comparison of plasma arsenic concentrations and toxicity between RIF and arsenic trioxide (ATO) treatment in APL may help to establish an appropriate therapeutic dose of RIF for children. From October 2018 to March 2020, 19 pediatric patients with APL treated with SCCLG-APL protocol were included, 9 in RIF group at 135 mg/kg/day orally three times daily, and 10 in ATO group at 0.16 mg/kg/day intravenously over 12 h daily. Peak and trough plasma arsenic concentrations were assayed at D1, 2, 7 and 14 of induction treatment. Urine arsenic excretions were assessed with spot urine samples and the measurements were adjusted using creatinine. Toxicities were compared between two groups. The plasma arsenic concentration reached steady state at D7 either in the RIF or ATO group, and the mean peak and trough concentrations were similar between two groups (P > 0.05), which were 0.54 µmol/L and 0.48 µmol/L in RIF group, and 0.63 µmol/L and 0.51 µmol/L in ATO group, respectively. Urine arsenic excretion rate was positively correlated with the concentration of plasma arsenic. The rates of treatment-related adverse events were similar in two groups. In conclusion, the dose of RIF at 135 mg/kg/day may be an appropriate therapeutic dose in children with APL. Urine arsenic level can be used as an indicator to estimate plasma arsenic concentration. Trial registration www.clinicaltrials.gov NCT02200978.

Effect of Kaempferol and Its Glycoside Derivatives on Antioxidant Status of HL-60 Cells Treated with Etoposide.

Kaempferol is a well-known antioxidant found in many plants and plant-based foods. In plants, kaempferol is present mainly in the form of glycoside derivatives. In this work, we focused on determining the effect of kaempferol and its glycoside derivatives on the expression level of genes related to the reduction of oxidative stress-NFE2L2, NQO1, SOD1, SOD2, and HO-1; the enzymatic activity of superoxide dismutases; and the level of glutathione. We used HL-60 acute promyelocytic leukemia cells, which were incubated with the anticancer drug etoposide and kaempferol or one of its three glycoside derivatives isolated from the aerial parts of Lens culinaris Medik.-kaempferol 3-O-[(6-O-E-caffeoyl)-ß-d-glucopyranosyl-(1→2)]-ß-d-galactopyranoside-7-O-ß-d-glucuropyranoside (P2), kaempferol 3-O-[(6-O-E-p-coumaroyl)-ß-d-glucopyranosyl-(1→2)]-ß-d-galactopyranoside-7-O-ß-d-glucuropyranoside (P5), and kaempferol 3-O-[(6-O-E-feruloyl)-ß-d-glucopyranosyl-(1→2)]-ß-d-galactopyranoside-7-O-ß-d-glucuropyranoside (P7). We showed that none of the tested compounds affected NFE2L2 gene expression. Co-incubation with etoposide (1 µM) and kaempferol (10 and 50 µg/mL) leads to an increase in the expression of the HO-1 (9.49 and 9.33-fold at 10 µg/mL and 50 µg/mL, respectively), SOD1 (1.68-fold at 10 µg/mL), SOD2 (1.72-fold at 10-50 µg/mL), and NQO1 (1.84-fold at 50 µg/mL) genes in comparison to cells treated only with etoposide. The effect of kaempferol derivatives on gene expression differs depending on the derivative. All tested polyphenols increased the SOD activity in cells co-incubated with etoposide. We observed that the co-incubation of HL-60 cells with etoposide and kaempferol or derivative P7 increases the level of total glutathione in these cells. Taken together, our observations suggest that the antioxidant activity of kaempferol is related to the activation of antioxidant genes and proteins. Moreover, we observed that glycoside derivatives can have a different effect on the antioxidant cellular systems than kaempferol.

Practice patterns and real-life outcomes for patients with acute promyelocytic leukemia in the United States.

Acute promyelocytic leukemia (APL) is associated with a favorable long-term prognosis if appropriate treatment is initiated promptly. Outcomes in clinical trials and population-based registries vary; potential explanations include a delay in treatment and lower adherence to guideline-recommended therapy in real-world practice. We used the Vizient Clinical Data Base to describe demographic characteristics, baseline clinical characteristics, and treatment patterns in patients newly diagnosed with APL during the study period of April 2017 to March 2020. Baseline white blood cell count was used to assign risk status and assess treatment concordance with National Comprehensive Cancer Network guidelines. Logistic regression models examined adjusted associations between patient, hospital, disease characteristics, and adverse outcomes (in-hospital death or discharge to hospice). Among 1464 patients with APL, 205 (14.0%) experienced an adverse outcome. A substantial subset (20.6%) of patients did not receive guideline-concordant regimens. Odds of adverse outcomes increased with failure to receive guideline-concordant treatment (odds ratio [OR], 2.31; 95% confidence interval [CI], 1.43-3.75; P = .001), high-risk disease (OR, 2.48; 95% CI, 1.53-4.00; P < .001), and increasing age (≥60 years: OR, 11.13; 95% CI, 4.55-27.22; P < .001). Higher hospital acute myeloid leukemia (AML) patient volume was associated with lower odds of adverse outcome (OR, 0.44; 95% CI, 0.20-0.99 [for ≤50 vs >200 AML patients per year]; P = .046). In conclusion, in this large database analysis, 14.0% of patients newly diagnosed with APL died or were discharged to hospice. A substantial proportion of patients did not receive guideline-concordant therapy, potentially contributing to adverse outcomes.

Hyperthermia Selectively Destabilizes Oncogenic Fusion Proteins.

The PML/RARα fusion protein is the oncogenic driver in acute promyelocytic leukemia (APL). Although most APL cases are cured by PML/RARα-targeting therapy, relapse and resistance can occur due to drug-resistant mutations. Here we report that thermal stress destabilizes the PML/RARα protein, including clinically identified drug-resistant mutants. AML1/ETO and TEL/AML1 oncofusions show similar heat shock susceptibility. Mechanistically, mild hyperthermia stimulates aggregation of PML/RARα in complex with nuclear receptor corepressors leading to ubiquitin-mediated degradation via the SIAH2 E3 ligase. Hyperthermia and arsenic therapy destabilize PML/RARα via distinct mechanisms and are synergistic in primary patient samples and in vivo, including three refractory APL cases. Collectively, our results suggest that by taking advantage of a biophysical vulnerability of PML/RARα, thermal therapy may improve prognosis in drug-resistant or otherwise refractory APL. These findings serve as a paradigm for therapeutic targeting of fusion oncoprotein-associated cancers by hyperthermia. SIGNIFICANCE: Hyperthermia destabilizes oncofusion proteins including PML/RARα and acts synergistically with standard arsenic therapy in relapsed and refractory APL. The results open up the possibility that heat shock sensitivity may be an easily targetable vulnerability of oncofusion-driven cancers.See related commentary by Wu et al., p. 300.

Successful treatment of acute promyelocytic leukemia in a 92-year-old man using all-trans retinoic acid combined with oral arsenic: A case report.

RATIONALE: Acute promyelocytic leukemia is a special subtype of acute myeloid leukemia. The incidence of early death and complications is high. An oral regimen of all-trans retinoic acid combined with the realgar-indigo naturalis formula (RIF) without chemotherapy has provided a new strategy for the treatment of these patients. PATIENT CONCERNS: A 92-year-old male patient was admitted to the hospital due to fatigue and oral bleeding. He had no fever or lung infection. Routine blood test showed white blood cell count 1.0 ×109/L, hemoglobin 100 g/L, and platelets 21 × 109/L. Coagulation function indicated fibrinogen 1.02 g/L and D-dimer 2360 ng/mL. And 28% abnormal promyelocytes were observed in peripheral blood. DIAGNOSIS: A bone marrow morphologic, immunophenotypic, cytogenetic, and molecular examination was performed. Routine bone marrow examination showed active proliferation of nucleated cells, with promyelocytes accounting for 91%; immunophenotyping revealed an early myeloid cell population, accounting for approximately 82.4% of all cells. INTERVENTIONS: From February 15, 2020, 25 mg/m2 all-trans retinoic acid was orally administered daily. After the fusion gene result was obtained, oral administration of 60 mg/kg RIF daily began since February 18, 2020. The combination of the 2 agents was given until March 16, 2020. Oral administration of 25 mg/m2 retinoic acid daily began from March 20, 2020 for 2 weeks, and oral administration of 60 mg/kg RIF daily lasted for 4 weeks as the consolidation therapy. During the treatment, the proportion of promyelocytes in peripheral blood, white blood cell count, platelets, coagulation function, liver function, and QT interval were monitored. OUTCOMES: Oral retinoic acid and oral RIF were given without chemotherapy and the patient achieved bone marrow remission after 1 month, and molecular remission was achieved 2 months later. In the early stage of acute promyelocytic leukemia, combined thrombocytopenia and disseminated intravascular coagulation may develop. Platelet and fresh frozen plasma infusion were proactively given until platelets were stabilized above 30 × 109/L, and the coagulation function returned to normal. LESSONS: The regimen was safe and effective, and subsequent treatment did not require hospitalization, which helped to improve the patient's quality of life.

Acute myeloid leukemia: Treatment and research outlook for 2021 and the MD Anderson approach.

The unraveling of the pathophysiology of acute myeloid leukemia (AML) has resulted in rapid translation of the information into clinical practice. After more than 40 years of slow progress in AML research, the US Food and Drug Administration has approved nine agents for different AML treatment indications since 2017. In this review, we detail the progress that has been made in the research and treatment of AML, citing key publications related to AML research and therapy in the English literature since 2000. The notable subsets of AML include acute promyelocytic leukemia (APL), core-binding factor AML (CBF-AML), AML in younger patients fit for intensive chemotherapy, and AML in older/unfit patients (usually at the age cutoff of 60-70 years). We also consider within each subset whether the AML is primary or secondary (therapy-related, evolving from untreated or treated myelodysplastic syndrome or myeloproliferative neoplasm). In APL, therapy with all-trans retinoic acid and arsenic trioxide results in estimated 10-year survival rates of ≥80%. Treatment of CBF-AML with fludarabine, high-dose cytarabine, and gemtuzumab ozogamicin (GO) results in estimated 10-year survival rates of ≥75%. In younger/fit patients, the "3+7" regimen (3 days of daunorubicin + 7 days of cytarabine) produces less favorable results (estimated 5-year survival rates of 35%; worse in real-world experience); regimens that incorporate high-dose cytarabine, adenosine nucleoside analogs, and GO are producing better results. Adding venetoclax, FLT3, and IDH inhibitors into these regimens has resulted in encouraging preliminary data. In older/unfit patients, low-intensity therapy with hypomethylating agents (HMAs) and venetoclax is now the new standard of care. Better low-intensity regimens incorporating cladribine, low-dose cytarabine, and other targeted therapies (FLT3 and IDH inhibitors) are emerging. Maintenance therapy now has a definite role in the treatment of AML, and oral HMAs with potential treatment benefits are also available. In conclusion, AML therapy is evolving rapidly and treatment results are improving in all AML subsets as novel agents and strategies are incorporated into traditional AML chemotherapy. LAY SUMMARY: Ongoing research in acute myeloid leukemia (AML) is progressing rapidly. Since 2017, the US Food and Drug Administration has approved 10 drugs for different AML indications. This review updates the research and treatment pathways for AML.

Transformation from acute promyelocytic leukemia to acute myeloid leukemia with a CEBPA double mutation: A case report and review of the literature.

INTRODUCTION: The transformation of acute promyelocytic leukemia (APL) to acute mononuclear leukemia during treatment is a rare clinical phenomenon, and no CCAAT/enhancer-binding protein alpha (CEBPA) double mutations have been reported. PATIENT CONCERNS: A 42-year-old male was hospitalized for ecchymosis of the left lower limb for more than 1 month, gingival bleeding, and fatigue for 10 days, with aggravation of symptoms for 2 days. DIAGNOSIS: A diagnosis of APL was based on bone marrow (BM) morphology, immunophenotyping, fusion gene analysis, and fluorescence in situ hybridization. At a 1-year follow-up of maintenance treatment, he developed thrombocytopenia and was diagnosed with acute myeloid leukemia (AML) with a CEBPA double mutation by BM morphology, immunotyping, chromosomal analysis, polymerase chain reaction, and next generation sequencing. INTERVENTIONS: Complete remission of APL was achieved after all-trans retinoic acid and arsenic trioxide double induction therapy, followed by 2 cycles of mitoxantrone and cytarabine, and 1 cycle of idarubicin and cytarabine. Thereafter, sequential maintenance therapy of arsenic trioxide + all-trans retinoic acid + methotrexate was started. In the fourth cycle of maintenance therapy, APL was transformed into AML with a CEBPA double mutation. After 1 cycle of idarubicin and cytarabine, the patient achieved complete remission and received 3 cycles of idarubicin and cytarabine and three cycles of high-dose cytarabine as consolidation therapy. OUTCOMES: At present, the patient is in continuous remission with minimal residual disease negative for both of APL and AML. CONCLUSION: AML with a CEBPA double mutation after APL treatment is very rare, thus the prognosis of this event will require further observation.