An effective and chemotherapy-free strategy of all-trans retinoic acid and arsenic trioxide for acute promyelocytic leukemia in all risk groups (APL15 trial)

Prognosis influence of additional chromosome abnormalities in newly diagnosed acute promyelocytic leukemia with t(15;17)(q24;q21)

OBJECTIVES

In patients with acute promyelocytic leukemia (APL), additional chromosomal abnormalities (ACAs) are prognostic indicators. However, the clinical features of ACAs were not systematically reported in Chinese patients. Therefore, we enrolled a large cohort of APLs to demonstrate the clinical characteristics and prognostic value of ACAs.

METHODS

268 patients with newly diagnosed APL with t(15;17)(q24;q21) were retrospectively enrolled, and their clinical characteristics and the predictive value of ACAs were assessed between patients with the presence and absence of ACAs.

RESULTS

APL patients with and without ACAs did not differ significantly in their clinical features or treatment response and clinical outcomes like overall survival (OS) and disease-free survival (DFS). It appeared to be substantially associated with worse OS in APL patients with trisomy 8, which was the most common ACA, although DFS was unaffected. Interestingly, the presence of ACAs or trisomy 8 affected OS and DFS in the subgroup of patients aged ≥60 years; by contrast, ACAs had no effect on OS or DFS in any treatment subgroup (ATRA + ATO/RIF or ATRA + ATO/RIF + CH or ATRA + CH), except for the ATRA + ATO/RIF + CH treatment subgroup, where their impact on DFS was less favorable.

CONCLUSIONS

Our results suggested that OS and DFS were unaffected by ACAs. Nonetheless, in the subgroup of patients older than 60, the existence of ACAs or trisomy 8 appeared to impact OS and DFS negatively. Individuals with t(15;17) alone had a higher DFS and were more susceptible to ATRA + ATO/RIF + CH than individuals with t(15;17) ACAs.

All-trans retinoic acid in hematologic disorders: not just acute promyelocytic leukemia

All-trans retinoic acid (ATRA) plays a role in tissue development, neural function, reproduction, vision, cell growth and differentiation, tumor immunity, and apoptosis. ATRA can act by inducing autophagic signaling, angiogenesis, cell differentiation, apoptosis, and immune function. In the blood system ATRA was first used with great success in acute promyelocytic leukemia (APL), where ATRA differentiated leukemia cells into mature granulocytes. ATRA can play a role not only in APL, but may also play a role in other hematologic diseases such as immune thrombocytopenia (ITP), myelodysplastic syndromes (MDS), non-APL acute myeloid leukemia (AML), aplastic anemia (AA), multiple myeloma (MM), etc., especially by regulating mesenchymal stem cells and regulatory T cells for the treatment of ITP. ATRA can also increase the expression of CD38 expressed by tumor cells, thus improving the efficacy of daratumumab and CD38-CART. In this review, we focus on the mechanism of action of ATRA, its role in various hematologic diseases, drug combinations, and ongoing clinical trials.

Maximizing arsenic trioxide's anticancer potential: Targeted nanocarriers for solid tumor therapy

Arsenic trioxide (ATO) has gained significant attention due to its promising therapeutic effects in treating different diseases, particularly acute promyelocytic leukemia (APL). Its potent anticancer mechanisms have been extensively studied. Despite the great efficacy ATO shows in fighting cancers, drawbacks in the clinical use are obvious, especially for solid tumors, which include rapid renal clearance and short half-life, severe adverse effects, and high toxicity to normal cells. Recently, the emergence of nanomedicine offers a potential solution to these limitations. The enhanced biocompatibility, excellent targeting capability, and desirable effectiveness have attracted much interest. Therefore, we summarized various nanocarriers for targeted delivery of ATO to solid tumors. We also provided detailed anticancer mechanisms of ATO in treating cancers, its clinical trials and shortcomings as well as the combination therapy of ATO and other chemotherapeutic agents for reduced drug resistance and synergistic effects. Finally, the future study direction and prospects were also presented.

Diagnosis and management of acute promyelocytic leukemia: Brazilian consensus guidelines 2024 on behalf of the Brazilian Association of Hematology, Hemotherapy and Cellular Therapy

Improvements in clinical assessment have occurred since the last published recommendations on the diagnosis and treatment of acute promyelocytic leukemia in 2013. Here, a committee of specialists of the Brazilian Association of Hematology, Hemotherapy and Cellular Therapy presents a comprehensive review on the current knowledge, focusing on the advances in diagnosis, risk assessment, and frontline and salvage therapy. The concept of urgent diagnosis is explored as well as the management of critical situations such as coagulopathy and differentiation syndrome. Recent adjustments in risk stratification based on white blood cell counts only are presented together with the incorporation of chemo-free regimens for non-high-risk patients. Special conditions such as acute promyelocytic leukemia in children, the elderly and pregnant women are discussed. Finally, acute promyelocytic leukemia is presented as a highly curable disease because of the real possibility of targeted therapy towards differentiation, and, paradoxically, as a serious and urgent condition that deserves prompt recognition and management to avoid early mortality.

ATPR induces acute promyelocytic leukemia cells differentiation and cycle arrest via the lncRNA CONCR/DDX11/PML-RARα signaling axis

Acute promyelocytic leukemia (APL) is a type of acute myeloid leukemia (AML) with a high mortality rate, and the production of PML-RARα fusion protein is the cause of its pathogenesis. Our group has synthesized a novel compound, 4-amino-2-trifluoromethyl-phenyl retinate (ATPR), by structural modification of All-trans retinoic acid (ATRA), which has strong cell differentiation-inducing effects and inhibits the expression of PML-RARα. In this study, acute promyelocytic leukemia NB4 cells before and after ATPR induction were analyzed by whole transcriptome microarray, and the expression of lncRNA CONCR was found to be significantly downregulated. The role of CONCR in ATPR-induced cell differentiation and cycle arrest was explored through overexpression and silencing of CONCR. And then the database was used to predict that CONCR may bind to DEAD/H-Box Helicase 11 (DDX11) protein to further explore the role of CONCR binding to DDX11. The results showed that ATPR could reduce the expression of CONCR, and overexpression of CONCR could reverse the ATPR-induced cell differentiation and cycle blocking effect, and conversely silencing of CONCR could promote this effect. RNA immunoprecipitation (RIP) experiments showed that CONCR could bind to DDX11, the protein expression levels of DDX11 and PML-RARα were elevated after overexpression of CONCR. These results suggest that ATPR can regulate the expression of DDX11 through CONCR to affect the expression of PML-RARα fusion protein, which in turn induces the differentiation and maturation of APL cells.

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.

Dynamic interplay of nuclear receptors in tumor cell plasticity and drug resistance: Shifting gears in malignant transformations and applications in cancer therapeutics

Recent advances have brought forth the complex interplay between tumor cell plasticity and its consequential impact on drug resistance and tumor recurrence, both of which are critical determinants of neoplastic progression and therapeutic efficacy. Various forms of tumor cell plasticity, instrumental in facilitating neoplastic cells to develop drug resistance, include epithelial-mesenchymal transition (EMT) alternatively termed epithelial-mesenchymal plasticity, the acquisition of cancer stem cell (CSC) attributes, and transdifferentiation into diverse cell lineages. Nuclear receptors (NRs) are a superfamily of transcription factors (TFs) that play an essential role in regulating a multitude of cellular processes, including cell proliferation, differentiation, and apoptosis. NRs have been implicated to play a critical role in modulating gene expression associated with tumor cell plasticity and drug resistance. This review aims to provide a comprehensive overview of the current understanding of how NRs regulate these key aspects of cancer biology. We discuss the diverse mechanisms through which NRs influence tumor cell plasticity, including EMT, stemness, and metastasis. Further, we explore the intricate relationship between NRs and drug resistance, highlighting the impact of NR signaling on chemotherapy, radiotherapy and targeted therapies. We also discuss the emerging therapeutic strategies targeting NRs to overcome tumor cell plasticity and drug resistance. This review also provides valuable insights into the current clinical trials that involve agonists or antagonists of NRs modulating various aspects of tumor cell plasticity, thereby delineating the potential of NRs as therapeutic targets for improved cancer treatment outcomes.

Superiority of anthracycline-free treatment in standard-risk acute promyelocytic leukemia: A systematic review and comparative epidemiological analysis

BACKGROUND

Recent advances in the treatment of acute promyelocytic leukemia (APML) have seen unprecedented improvements in patient outcomes. However, such rapid growth in understanding often leads to uncertainty regarding superiority among candidate treatment regimens, especially when further scrutinized from an epidemiological perspective.

AIMS

The aim of this systematic review with epidemiological analysis was to identify and compare commonly utilized protocols for standard-risk APML with a particular focus on complete remission (CR), overall/disease-free survival (DFS), and reported adverse events.

METHODS AND RESULTS

Medline, Scopus, and CINAHL were interrogated to identify studies utilizing all-trans retinoic acid (ATRA) in addition to arsenic trioxide (ATO) and/or anthracyclines such as idarubicin (IDA) in the treatment of de-novo APML. After collation of studies, an epidemiological analysis was subsequently performed to compare protocols with regards to outcomes of interest using number needed to benefit (NNB) and number needed to harm (NNH) measures. Seventeen articles, describing 12 distinct trials, were included in the analysis. These trials made use of three unique protocols; CR rates were 94%-100% for ATO/ATRA regimens, 95%-96% for ATO/ATRA/anthracycline regimens, and 89%-94% for ATRA/anthracycline regimens. Epidemiological analysis demonstrated NNB for CR was 9.09 (ATO/ATRA vs. ATRA/IDA) and 20.00 (ATO/ATRA vs. ATO/ATRA/IDA), NNH for neutropenia was -3.45 (ATO/ATRA vs. ATRA/IDA), and NNH for infection was -3.13 (ATO/ATRA vs. ATRA/IDA) and -1.89 (ATO/ATRA vs. ATO/ATRA/IDA).

CONCLUSION

The ATO/ATRA regimen is superior to chemotherapy-containing protocols at inducing remission and promoting survival in patients with APML. The regimen is better tolerated than the proposed alternatives with fewer adverse events. Future research opportunities include quantifying APML epidemiology and pursuing oral arsenic as an option for simplification of therapeutic protocols.

Acute leukemias and complicated lymphomas: pearls to optimize management when patients stay local

Hematologic malignancies often present acutely with a constellation of infectious complications, pancytopenia, tumor lysis, and renal dysfunction. Acute leukemias and aggressive lymphomas often require hospitalization for rapid diagnostic evaluation, urgent management of complicating presentations, and timely management of intensive systemic therapies. There is an emerging paradigm whereby complex cancer care can be safely and effectively provided in the community, where the majority of cancer is treated. A substantive and effective network between local oncologists and their academic counterparts will enhance care for the patient, advance research, and help bring complicated therapies to local centers, thereby improving access. Here we present several cases that highlight a collaborative approach to complicated hematologic malignancies in the community.

The anti-leukemia activity and mechanisms of shikonin: a mini review

Leukemia encompasses a group of highly heterogeneous diseases that pose a serious threat to human health. The long-term outcome of patients with leukemia still needs to be improved and new effective therapeutic strategies continue to be an unmet clinical need. Shikonin (SHK) is a naphthoquinone derivative that shows multiple biological function includes anti-tumor, anti-inflammatory, and anti-allergic effects. Numerous studies have reported the anti-leukemia activity of SHK during the last 3 decades and there are studies showing that SHK is particularly effective towards various leukemia cells compared to solid tumors. In this review, we will discuss the anti-leukemia effect of SHK and summarize the underlying mechanisms. Therefore, SHK may be a promising agent to be developed as an anti-leukemia drug.

Febuxostat alleviates Arsenic Trioxide-Induced renal injury in Rats: Insights on the crosstalk between NLRP3/TLR4, Sirt-1/NF-κB/TGF-β signaling Pathways, and miR-23b-3p, miR-181a-5b expression

Febuxostat (FBX), a xanthine oxidase inhibitor, is known to improve renal function and can show promise as a therapeutic agent for preventing drug-induced nephrotoxicity. This study aimed to explore the protective effect of FBX in preventing renal damage caused by arsenic trioxide (ATO) toxicity and uncover the underlying mechanisms. The researchers examined how FBX (10 mg/kg, orally) affected ATO-induced kidney injury (5 mg/kg, intraperitoneally) in rats. Kidney function and toxicity parameters in serum and oxidative stress biomarkers and inflammatory cytokine levels in renal tissue were measured. H&E staining was used to detect histopathological changes in the kidney. Network the molecular mechanisms of FBX in improving kidney injury were investigated using Western blotting and PCR techniques. The findings showed that FBX improved kidney function by inhibiting the pathological changes seen in H&E staining, decreasing levels of probed kidney function and toxicity measures in serum and tissue, and exhibiting antioxidant and anti-inflammatory effects. FBX decreased MDA, MPO, TNF-α, IL-1β, IL-6, COX-II, and NADPH oxidase levels, while increased GSH, GPx, SOD, and IL-10 levels. FBX also reduced the expression of NLRP3, ASC, TLR4, and micro-RNA 181a-5b while increased the expression of IKBα, Sirt-1, and micro-RNA 23b-3p, according to Western blotting and PCR results. In conclusion, FBX can play a vital role in reducing kidney injury in cases of ATO-induced nephrotoxicity, though more clinical research needs to be conducted.

The Promise of Retinoids in the Treatment of Cancer: Neither Burnt Out Nor Fading Away

Since the introduction of all-trans retinoic acid (ATRA), acute promyelocytic leukemia (APL) has become a highly curable malignancy, especially in combination with arsenic trioxide (ATO). ATRA's success has deepened our understanding of the role of the RARα pathway in normal hematopoiesis and leukemogenesis, and it has influenced a generation of cancer drug development. Retinoids have also demonstrated some efficacy in a handful of other disease entities, including as a maintenance therapy for neuroblastoma and in the treatment of cutaneous T-cell lymphomas; nevertheless, the promise of retinoids as a differentiating therapy in acute myeloid leukemia (AML) more broadly, and as a cancer preventative, have largely gone unfulfilled. Recent research into the mechanisms of ATRA resistance and the biomarkers of RARα pathway dysregulation in AML have reinvigorated efforts to successfully deploy retinoid therapy in a broader subset of myeloid malignancies. Recent studies have demonstrated that the bone marrow environment is highly protected from exogenous ATRA via local homeostasis controlled by stromal cells expressing CYP26, a key enzyme responsible for ATRA inactivation. Synthetic CYP26-resistant retinoids such as tamibarotene bypass this stromal protection and have shown superior anti-leukemic effects. Furthermore, recent super-enhancer (SE) analysis has identified a novel AML subgroup characterized by high expression of RARα through strong SE levels in the gene locus and increased sensitivity to tamibarotene. Combined with a hypomethylating agent, synthetic retinoids have shown synergistic anti-leukemic effects in non-APL AML preclinical models and are now being studied in phase II and III clinical trials.

ATO Increases ROS Production and Apoptosis of Cells by Enhancing Calpain-Mediated Degradation of the Cancer Survival Protein TG2

Transglutaminase 2 (TG2) is a critical cancer cell survival factor that activates several signalling pathways to foster drug resistance, cancer stem cell survival, metastasis, inflammation, epithelial-mesenchymal transition, and angiogenesis. All-trans retinoic acid (ATRA) and chemotherapy have been the standard treatments for acute promyelocytic leukaemia (APL), but clinical studies have shown that arsenic trioxide (ATO), alone or in combination with ATRA, can improve outcomes. ATO exerts cytotoxic effects in a variety of ways by inducing oxidative stress, genotoxicity, altered signal transduction, and/or epigenetic modification. In the present study, we showed that ATO increased ROS production and apoptosis ratios in ATRA-differentiated NB4 leukaemia cells, and that these responses were enhanced when TG2 was deleted. The combined ATRA + ATO treatment also increased the amount of nuclear factor erythroid 2-related factor 2 (NRF2) transcription factor, an adaptive regulator of the cellular oxidative stress response, and calpain proteolytic activity, resulting in TG2 degradation and the reduced survival of WT leukaemia cells. We further showed that the induced TG2 protein expression was degraded in the MCF-7 epithelial cell line and primary peripheral blood mononuclear cells upon ATO treatment, thereby sensitising these cell types to apoptotic signals.

The Application of GHRH Antagonist as a Treatment for Resistant APL

GHRH is a hypothalamic peptide shown to stimulate the proliferation of malignant cells in humans. We have previously shown that the use of GHRH antagonist MIA-602 successfully suppressed the growth of many human cancer cell lines, spanning more than 20 types of cancers. In this study, we demonstrate the presence of GHRH-R in the NB4, NB4-RAA, and K-562 model cell lines. Furthermore, we demonstrate the inhibited proliferation of all three cell lines in vitro after incubation with MIA-602. The treatment of xenografts of human APL cell lines with MIA-602 led to a significant reduction in tumor growth. Additionally, combination therapy with both doxorubicin (DOX) and MIA-602 showed a marked synergistic effect in reducing the proliferation of the K-562 AML cell line. These findings suggest that MIA-602 could be utilized to address resistance to all-trans retinoic acid (ATRA) and arsenic trioxide (ATO) therapies, as well as in augmenting anthracycline-based regimens.

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.

The genomic landscape of sensitivity to arsenic trioxide uncovered by genome-wide CRISPR-Cas9 screening

Introduction

Arsenic trioxide (ATO) is a promising anticancer drug for hematological malignancy. Given the dramatic efficacy of acute promyelocytic leukemia (APL), ATO has been utilized in other types of cancers, including solid tumors. Unfortunately, the results were not comparable with the effects on APL, and the resistance mechanism has not been clarified yet. This study intends to identify relevant genes and pathways affecting ATO drug sensitivity through genome-wide CRISPR-Cas9 knockdown screening to provide a panoramic view for further study of ATO targets and improved clinical outcomes.

Methods

A genome-wide CRISPR-Cas9 knockdown screening system was constructed for ATO screening. The screening results were processed with MAGeCK, and the results were subjected to pathway enrichment analysis using WebGestalt and KOBAS. We also performed protein-protein interaction (PPI) network analysis using String and Cytoscape, followed by expression profiling and survival curve analysis of critical genes. Virtual screening was used to recognize drugs that may interact with the hub gene.

Results

We applied enrichment analysis and identified vital ATO-related pathways such as metabolism, chemokines and cytokines production and signaling, and immune system responses. In addition, we identified KEAP1 as the top gene relating to ATO resistance. We found that KEAP1 expression was higher in the pan-cancer, including ALL, than in normal tissue. Patients with acute myeloid leukemia (AML) with higher KEAP1 expression had worse overall survival (OS). A virtual screen showed that etoposide and eltrombopag could bind to KEAP1 and potentially interact with ATO.

Discussion

ATO is a multi-target anticancer drug, and the key pathways regulating its sensitivity include oxidative stress, metabolism, chemokines and cytokines, and the immune system. KEAP1 is the most critical gene regulating ATO drug sensitivity, which is related to AML prognosis and may bind to some clinical drugs leading to an interaction with ATO. These integrated results provided new insights into the pharmacological mechanism of ATO and potentiate for further applications in cancer treatments.