Arsenic trioxide is an approved chemotheraputic agent for the treatment of acute promyelocytic leukemia (APL). Recently, numerous studies suggested that arsenic trioxide acts as anti-cancer roles in various human malignancies. However, the molecular mechanisms are not fully elucidated. In this study, we explored the critical targets of arsenic trioxide and their interaction network systematically by searching the publicly available published database like DrugBank (DB) and STRING. Seven direct protein targets (DPTs) and 111 DPT-associated genes were identified. The enrichment analysis of arsenic trioxide associated genes/proteins revealed 10 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Among these pathways, phosphatidylinositol-4,5-bisphosphate-3-kinase -Akt (PI3K-Akt) single pathway and pancreatic cancer pathway are highly correlated with arsenic trioxide and have 5 overlapped targets. Then we investigated the gene alternation of selected critical genes in pancreatic cancer studies using cBio portal. These results indicated that arsenic trioxide could act anti-tumor function through PI3K-Akt single pathway and identified critical genes might be therapeutic targets for pancreatic cancer.

Arsenic trioxide (As₂O₃), a traditional remedy in Chinese medicine, has been used in acute promyelocytic leukemia (APL) research and clinical treatment. Previous studies have shown that As₂O₃ exerts its potent antitumor effects in solid tumors by regulating cell proliferation and survival. The aim of this study was to investigate whether As₂O₃ inhibited gastric cancer cell migration and angiogenesis by regulating FOXO3a expression. We found that As₂O₃ reduced gastric cancer cell viability in a dose-dependent manner and also inhibited cell migration and angiogenesis in vitro. Western blotting and immunofluorescence showed that As₂O₃ downregulated the levels of p-AKT, upregulated FOXO3a expression in the nucleus, and attenuated downstream Vascular endothelial growth factor (VEGF) and Matrix metallopeptidase 9 (MMP9) expression. Moreover, we demonstrated that knockdown of FOXO3a significantly reversed the inhibition of As₂O₃ and promoted cell migration and angiogenesis in vitro. Further, As₂O₃ significantly inhibited xenograft tumor growth and angiogenesis by upregulating FOXO3a expression in vivo. However, knockdown of FOXO3a attenuated the inhibitory effect of As₂O₃ in xenograft tumors, and increased microvessel density (MVD) and VEGF expression. Our results demonstrated that As₂O₃ inhibited migration and angiogenesis of gastric cancer cells by enhancing FOXO3a expression.

In this work, we investigated the stability of arsenic trioxide (ATO) used in leukemia treatment, encapsulated with nanoliposome, with the aid of ultrasound treatment. Stability studies of As species were followed by liquid chromatography-inductively coupled plasma mass spectrometry (LC-ICP-MS), allowing for the detection of the conversion of low amounts of As(III) to As(V) or the formation of other As species. The influence of storage temperature and time on ATO was evaluated. Low amounts of As(III) to As(V) conversions were observed when the As encapsulated with nanoliposome was incubated at 25 °C and 40 °C. However, As(III) was stable if the solution was maintained at 5 °C, even after 90 days. No formation of other As species was observed, indicating good stability of the encapsulated ATO. Next step of the work will focus on spray drying of ATO nanoliposomes-encapsuleted with the aim of long term stability of As.

High expression of the oncogene ecotropic viral integration site-1 (EVI-1) is an independent negative prognostic indicator of survival in leukemia patients. This study aimed to examine the effects of arsenic trioxide (ATO) on EVI-1 in acute myeloid leukemia (AML). Mononuclear cells were isolated from the bone marrow and peripheral blood of AML patients and healthy donors. EVI-1 expression in hematopoietic cells was evaluated by RT-qPCR and Western blot analysis. EVI-1 was highly expressed in both primary AML and leukemia cell lines (THP-1 and K562). ATO down-regulated EVI-1 mRNA in zebrafish in vivo as well as in primary leukemia cells and THP-1 and K562 cells in vitro. Additionally, ATO treatment induced apoptosis, down-regulated both EVI-1 mRNA and oncoprotein expression, increased the expression of pro-apoptosis proteins, and decreased the expression of anti-apoptotic proteins in leukemia cells in vitro. EVI-1 expression in leukemia cells (THP-1 and K562) transduced with EVI-1 siRNA was significantly reduced. Silencing EVI-1 had a significant effect on the activation of the JNK pathway and the induction of leukemia cell apoptosis. ATO may downregulate EVI-1 mRNA and oncoprotein levels and block the inhibitory effects of EVI-1 on the JNK pathway, which activates the JNK apoptotic pathway, thereby leading to the apoptosis of EVI-1 in AML patients.

CD147 is a transmembrane glycoprotein with multiple functions in human healthy tissues and diseases, in particular in cancer. Overexpression of CD147 correlates with biological functions that promote tumor progression and confers resistance to chemotherapeutic drugs. In contrast to solid tumors, the role of CD147 has not been extensively studied in leukemia. Understanding whether CD147 represents a new hematological target and whether its inhibitor AC-73 may be used in leukemia therapy, may reveal an alternative treatment strategy in patients with acute myeloid leukemia. We analyzed CD147 expression and function in hematopoietic progenitor cells from normal cord blood, in several leukemic cell lines and in primary leukemic blasts obtained from patients with acute myeloid leukemia. We investigated the effects of AC-73, used alone or in combination with arabinosylcytosine (Ara-C) and arsenic trioxide (ATO), on leukemic cell proliferation. In our study, we demonstrated that CD147 overexpression promotes leukemic cell proliferation. We showed that AC-73 exhibits a potent growth inhibitory activity in leukemic cells, by inhibiting the ERK/STAT3 activation pathway and activating autophagy. We demonstrated that AC-73 exerts an anti-proliferative effect additive to chemotherapy, by enhancing leukemic cells sensitivity to Ara-C-induced cytotoxicity or to ATO-induced autophagy. We also reported CD147 expression in the fraction of leukemic blasts expressing CD371, a marker of leukemic stem cells. Altogether, our study indicates CD147 as a novel potential target in the treatment of acute myeloid leukemia and AC-73 as an anti-proliferative drug and an inducer of autophagy in leukemic cells to use in combination with chemotherapeutic agents.

Cisplatin (CDDP) and arsenic trioxide (ATO), two representative inorganic anticancer drugs, have been successful in the treatment against several kinds of malignancies. However, combination therapy with these two drugs in clinical application suffers from poor pharmacokinetics, serious side effects, and drug resistance of the tumor. Herein, we report a carrier-free aquo-cisplatin arsenite multidrug nanocomposite loaded with cisplatin and arsenic trioxide prodrugs simultaneously. This nanocomposite achieves a high loading capacity and pH-dependent controlled release of the drugs. Because of these features, this nanocomposite shows better in vitro toxicity against various carcinoma cell lines than either the single drug or free drug combination, promotes the synergistic effect of cisplatin and arsenic trioxide, and significantly inhibits the growth of tumors in vivo. Furthermore, cisplatin and arsenic trioxide in this nanocomposite can realize a coordination of both enhanced DNA damage and DNA repair interference within cisplatin-resistant cells, which results in overcoming the drug resistance effectively. Gene expression profiles demonstrate the reduced expression of proto-oncogenes and DNA damage repair related genes MYC, MET, and MSH2, along with the increase of tumor suppressor genes PTEN, VHL, and FAS after the nanocomposite treatment. This type of multidrug nanocomposite offers an alternative and promising strategy for combination therapy and overcoming drug resistance.

Forty-seven sediment cores were collected as part of a spatial survey of Long Lake, Yellowknife, NWT, Canada to elucidate the physical and geochemical controls on the distribution of arsenic (As) in sediments impacted by the aerial deposition of arsenic trioxide (As2O3) from ore roasting at legacy gold mines. High-resolution profiles of dissolved As in bottom water and porewater were also collected to determine As remobilization and diffusion rates across the sediment-water interface. Arsenic concentrations in Long Lake sediments ranged from 2.2 to 3420 mg kg-1 (dry weight). Two distinct types of sediment As concentration profiles were identified and are interpreted to represent erosional and depositional areas. Water depth is the best predictor of As concentration in the top 5 cm of sediments due to the inferred focusing of fine-grained As2O3 into deeper water. At greater sediment depths, iron (Fe) concentration, as a likely indicator of As, Fe, and sulphur (S) co-diagenesis, was the best predictor of As concentration. The sediments are a source of dissolved As to surface waters through diffusion-controlled release to bottom water. Arsenic concentrations, solid-phase speciation, and diffusive efflux varied laterally across the lake bottom and with sediment depth due to the interplay between sediment-focusing processes and redox reactions, which has implications for human health and ecological risk assessments.

The National Institute for Health and Care Excellence (NICE) invited Teva, the company manufacturing arsenic trioxide (ATO; tradename Trisenox®), to submit evidence for the clinical and cost effectiveness of ATO for untreated and relapsed or refractory acute promyelocytic leukaemia (APL). Kleijnen Systematic Reviews Ltd (KSR), in collaboration with Maastricht University Medical Center, was commissioned as the independent Evidence Review Group (ERG). This paper presents a summary of the company submission (CS), the ERG's critical review of the clinical and cost effectiveness evidence in the CS, key methodological considerations and the development of the NICE guidance by the Appraisal Committee (AC). The CS presented three randomized controlled trials (RCTs). Two of these were trials in newly diagnosed APL (APL0406 and AML17) and the third trial was in patients with relapsed APL. Results from APL0406 showed that more people having AATO [ATO plus all-trans retinoic acid (ATRA)] were alive at 50 months compared with people having AIDA (ATRA in combination with idarubicin) (99% vs. 93%; p = 0.007). There was also a statistically significant lower cumulative incidence of relapse with AATO compared with AIDA at 50 months (2% vs. 14%; p = 0.001). At 4 years, results from AML17 showed a significant difference in event-free survival (91% vs. 70%; p = 0.002) favouring AATO but not in overall survival (93% vs. 89%; p = 0.250). The only trial presented for relapsed/refractory patients compared AATO with ATO, which was not a relevant comparison according to the NICE scope. The AC concluded that AATO was effective for untreated APL while for relapsed or refractory APL the effectiveness of ATO was considered uncertain and the long-term safety remains unexplored. In the CS base-case, AATO was less expensive (£31,088 saved) and more effective (2.546 quality-adjusted life-years (QALYs) gained) than AIDA and thus the dominating strategy for newly diagnosed low- to intermediate-risk APL. However, the ERG's critical assessment highlighted a number of concerns, including deviations from the NICE reference case and a lack of detailed description and justification of parameters and assumptions related to (the extrapolation of) treatment effectiveness. However, it was reassuring that AATO for untreated APL remained dominant in the ERG base-case, and that the worst-case scenario produced by the ERG resulted in an incremental cost-effectiveness ratio (ICER) of £21,622. The AC concluded that although there was uncertainty in the model, it could recommend ATO for both untreated and relapsed or refractory APL.

The fate of disseminated tumor cells is largely determined by microenvironment (ME) niche. The osteogenic niche promotes cancer cell proliferation and bone metastasis progression. We investigated the underlying mechanisms using pre-clinical models and analyses of clinical data. We discovered that the osteogenic niche serves as a calcium (Ca) reservoir for cancer cells through gap junctions. Cancer cells cannot efficiently absorb Ca from ME, but depend on osteogenic cells to increase intracellular Ca concentration. The Ca signaling, together with previously identified mammalian target of rapamycin signaling, promotes bone metastasis progression. Interestingly, effective inhibition of these pathways can be achieved by danusertib, or a combination of everolimus and arsenic trioxide, which provide possibilities of eliminating bone micrometastases using clinically established drugs.

The treatment of acute promyelocytic leukemia (APL) has evolved rapidly in the past two decades after the introduction of highly active drugs, including tretinoin (all- trans-retinoic acid) and arsenic trioxide. It is now possible to treat this disease without the use of traditional cytotoxic chemotherapy. Today's clinical guidelines include multiple regimens, some of which continue to use cytotoxic chemotherapy. This leaves the practicing oncologist with multiple treatment options when faced with a new case of APL. In an effort to standardize our approach to the treatment of newly diagnosed APL, we sought to develop a set of treatment recommendations at our institution. We identified eight major controversial issues in the treatment of APL. These controversial issues include the optimal dose and schedule of both all- trans-retinoic acid and arsenic trioxide, the optimal regimen for high-risk APL, the need for intrathecal prophylaxis, the use of prophylactic corticosteroids, and the need for maintenance therapy after consolidation. We reviewed the relevant literature and used the Delphi method among the coauthors to reach consensus for recommendations on the basis of the best available data and our own clinical experience. In this clinical review, we present our consensus recommendations, the reasoning behind them, and the grading of the evidence that supports them.