Memory effects of prior subculture may impact the quality of multiomic perturbation profiles.

Mass spectrometry-based omics technologies are increasingly used in perturbation studies to map drug effects to biological pathways by identifying significant molecular events. Significance is influenced by fold change and variation of each molecular parameter, but also by multiple testing corrections. While the fold change is largely determined by the biological system, the variation is determined by experimental workflows. Here, it is shown that memory effects of prior subculture can influence the variation of perturbation profiles using the two colon carcinoma cell lines SW480 and HCT116. These memory effects are largely driven by differences in growth states that persist into the perturbation experiment. In SW480 cells, memory effects combined with moderate treatment effects amplify the variation in multiple omics levels, including eicosadomics, proteomics, and phosphoproteomics. With stronger treatment effects, the memory effect was less pronounced, as demonstrated in HCT116 cells. Subculture homogeneity was controlled by real-time monitoring of cell growth. Controlled homogeneous subculture resulted in a perturbation network of 321 causal conjectures based on combined proteomic and phosphoproteomic data, compared to only 58 causal conjectures without controlling subculture homogeneity in SW480 cells. Some cellular responses and regulatory events were identified that extend the mode of action of arsenic trioxide (ATO) only when accounting for these memory effects. Controlled prior subculture led to the finding of a synergistic combination treatment of ATO with the thioredoxin reductase 1 inhibitor auranofin, which may prove useful in the management of NRF2-mediated resistance mechanisms.

Vitamin C enhances the sensitivity of osteosarcoma to arsenic trioxide via inhibiting aerobic glycolysis.

Osteosarcoma (OS) is a common malignant tumor disease in the department of orthopedics, which is prone to the age of adolescents and children under 20 years old. Arsenic trioxide (ATO), an ancient poison, has been reported to play a critical role in a variety of tumor treatments, including OS. However, due to certain poisonous side effects such as cardiotoxicity and hepatotoxicity, clinical application of ATO has been greatly limited. Here we report that low doses of ATO (1 µM) observably reduced the half-effective inhibitory concentration (IC50) of vitamin C on OS cells. Compared with the treatment alone, the synthetic application of vitamin C (VitC, 800 µM) and ATO (1 µM) significantly further inhibited the proliferation, migration, and invasion of OS cells and promoted cell apoptosis in vitro. Meanwhile, we observed that the combined application of VitC and ATO directly suppresses the aerobic glycolysis of OS cells with the decreased production of pyruvate, lactate, and ATP via inhibiting the expression of the critical glycolytic genes (PGK1, PGM1, and LDHA). Moreover, the combination of VitC (200 mg/kg) and ATO (1 mg/kg) with tail vein injection significantly delayed OS growth and migration of nude mice by inhibiting aerobic glycolysis of OS. Thus, our results demonstrate that VitC effectively increases the sensitivity of OS to low concentrations of ATO via inhibiting aerobic glycolysis to alleviate the toxic side effects of high doses of arsenic trioxide, suggesting that synthetic application of VitC and ATO is a promising approach for the clinical treatment of human OS.

Inhibition of NRF2 signaling overcomes acquired resistance to arsenic trioxide in FLT3-mutated Acute Myeloid Leukemia.

De novo acute myeloid leukemia (AML) patients with FMS-like tyrosine kinase 3 internal tandem duplications (FLT3-ITD) have worse treatment outcomes. Arsenic trioxide (ATO) used in the treatment of acute promyelocytic leukemia (APL) has been reported to be effective in degrading the FLT3 protein in AML cell lines and sensitizing non-APL AML patient samples in-vitro. We have previously reported that primary cells from FLT3-ITD mutated AML patients were sensitive to ATO in-vitro compared to other non-M3 AML and molecular/pharmacological inhibition of NF-E2 related factor 2 (NRF2), a master regulator of antioxidant response improved the chemosensitivity to ATO and daunorubicin even in non FLT3-ITD mutated cell lines and primary samples. We examined the effects of molecular/pharmacological suppression of NRF2 on acquired ATO resistance in the FLT3-ITD mutant AML cell line (MV4-11-ATO-R). ATO-R cells showed increased NRF2 expression, nuclear localization, and upregulation of bonafide NRF2 targets. Molecular inhibition of NRF2 in this resistant cell line improved ATO sensitivity in vitro. Digoxin treatment lowered p-AKT expression, abrogating nuclear NRF2 localization and sensitizing cells to ATO. However, digoxin and ATO did not sensitize non-ITD AML cell line THP1 with high NRF2 expression. Digoxin decreased leukemic burden and prolonged survival in MV4-11 ATO-R xenograft mice. We establish that altering NRF2 expression may reverse acquired ATO resistance in FLT3-ITD AML.

Transcatheter arterial chemoembolization using CalliSpheres beads loaded with arsenic trioxide for unresectable large or huge hepatocellular carcinoma: a prospective study.

OBJECTIVES: To determine the safety and efficacy of transcatheter arterial chemoembolization with CalliSpheres® beads loaded with arsenic trioxide (CBATO-TACE) in the first-line treatment of patients with large (5 cm ≤ maximum diameter < 10 cm) or huge (maximum diameter ≥ 10 cm) hepatocellular carcinoma (HCC). METHODS: Patients were randomly allocated to the CBATO-TACE group and the conventional transcatheter arterial chemoembolization (cTACE) group. The primary endpoint was progression-free survival (PFS). The secondary endpoint was overall survival (OS), treatment response, and treatment-related adverse events (TRAEs). The extrahepatic collateral arteries, liver function, and liver fibrosis after the first TACE were also evaluated. RESULTS: From September 2018 to September 2020, a total of 207 patients who underwent TACE were consecutively enrolled in this study. The median PFS was 9.5 months (range: 8.0 - 11.0) in the CBATO group, which was significantly longer than that in the cTACE group (6.0 months, range: 4.0-6.0) (p < 0.0001). Patients in the CBATO group had a median OS of 22 months (range: 20.0 - 27.0) compared with 16 months (range: 15.0 - 20.0) in the cTACE group (p = 0.0084). The most common TRAEs were fever (p = 0.043), and nausea and vomiting (p = 0.002), which were more observed in the cTACE group. In addition, the progressive disease time, pulmonary metastasis rate (p = 0.01), the mean number of extrahepatic collateral arteries (p = 0.01), and average number of TACE sessions (p = 0.025) were significantly decreased in the CBATO group. CONCLUSIONS: CBATO-TACE achieved better therapeutic outcomes and similar safety profile compared to cTACE in large or huge HCC patients. Furthermore, CBATO-TACE was able to reduce extrahepatic collateral arteries production and extrahepatic lung metastasis. CLINICAL RELEVANCE STATEMENT: Our study showed that CalliSpheres® beads loaded with arsenic trioxide (CBATO-TACE) were effective and safe for the treatment of large and giant HCC. In addition, CBATO-TACE can reduce lateral hepatic branch artery formation and extrahepatic pulmonary metastasis, which provides a new treatment approach for unresectable HCC. KEY POINTS: • We compare long-term efficacy and safety of transcatheter arterial chemoembolization with CalliSpheres® beads loaded with arsenic trioxide (CBATO-TACE) and conventional transcatheter arterial chemoembolization (cTACE) in patients with large (5 cm ≤ maximum diameter < 10 cm) or huge HCC (maximum diameter ≥ 10 cm). • Compared with cTACE, CBATO-TACE significantly improved therapeutic outcomes, overall survival, and progression-free survival in patients with large or huge HCC. The safety assessment suggested that CBATO-TACE is a safe treatment that improves the quality of life and has good treatment adherence.

Gaillardin exerts potent antileukemic effects on HL-60 cells and intensifies arsenic trioxide cytotoxicity: Providing new insight into sesquiterpene lactones in leukaemia treatment.

The use of all-trans retinoic acid and arsenic trioxide resulted in favourable therapeutic responses in standard-risk acute promyelocytic leukaemia (APL) patients. However, resistance to these agents has made treating the high-risk subgroup more problematic, and possible side effects limit their clinical dosages. Numerous studies have proven the cytotoxic properties of Gaillardin, one of the Inula oculus-christi-derived sesquiterpene lactones. Due to the adverse effects of arsenic trioxide on the high-risk subgroup of APL patients, we aimed to assess the cytotoxic effect of Gaillardin on HL-60 cells as a single or combined-form approach. The results of the trypan blue and MTT assays outlined the potent cytotoxic properties of Gaillardin. The flow cytometric analysis and the mRNA expression levels revealed that Gaillardin attenuated the proliferative capacity of HL-60 cells through cell cycle arrest and induced apoptosis via reactive oxygen species generation. Moreover, the results of synergistic experiments indicated that this sesquiterpene lactone sensitizes HL-60 cells to the cytotoxic effects of arsenic trioxide. Taken together, the findings of the present investigation highlighted the antileukemic characteristics of Gaillardin by inducing G1 cell cycle arrest and triggering apoptosis. Gaillardin acts as an antileukemic metabolite against HL-60 cells and this study provides new insight into treating APL patients, especially in the high-risk subgroup.

Function of PML-RARA in Acute Promyelocytic Leukemia.

The transformation of acute promyelocytic leukemia (APL) from the most fatal to the most curable subtype of acute myeloid leukemia (AML), with long-term survival exceeding 90%, has represented one of the most exciting successes in hematology and in oncology. APL is a paradigm for oncoprotein-targeted cure.APL is caused by a 15/17 chromosomal translocation which generates the PML-RARA fusion protein and can be cured by the chemotherapy-free approach based on the combination of two therapies targeting PML-RARA: retinoic acid (RA) and arsenic. PML-RARA is the key driver of APL and acts by deregulating transcriptional control, particularly RAR targets involved in self-renewal or myeloid differentiation, also disrupting PML nuclear bodies. PML-RARA mainly acts as a modulator of the expression of specific target genes: genes whose regulatory elements recruit PML-RARA are not uniformly repressed but also may be upregulated or remain unchanged. RA and arsenic trioxide directly target PML-RARA-mediated transcriptional deregulation and protein stability, removing the differentiation block at promyelocytic stage and inducing clinical remission of APL patients.

Arsenic trioxide replacing or reducing chemotherapy in consolidation therapy for acute promyelocytic leukemia (APL2012 trial).

As all-trans retinoic acid (ATRA) and arsenic trioxide (ATO) are widely accepted in treating acute promyelocytic leukemia (APL), deescalating toxicity becomes a research hotspot. Here, we evaluated whether chemotherapy could be replaced or reduced by ATO in APL patients at different risks. After achieving complete remission with ATRA-ATO-based induction therapy, patients were randomized (1:1) into ATO and non-ATO groups for consolidation: ATRA-ATO versus ATRA-anthracycline for low-/intermediate-risk patients, or ATRA-ATO-anthracycline versus ATRA-anthracycline-cytarabine for high-risk patients. The primary end point was to assess disease-free survival (DFS) at 3 y by a noninferiority margin of -5%; 855 patients were enrolled with a median follow-up of 54.9 mo, and 658 of 755 patients could be evaluated at 3 y. In the ATO group, 96.1% (319/332) achieved 3-y DFS, compared to 92.6% (302/326) in the non-ATO group. The difference was 3.45% (95% CI -0.07 to 6.97), confirming noninferiority (P < 0.001). Using the Kaplan-Meier method, the estimated 7-y DFS was 95.7% (95% CI 93.6 to 97.9) in ATO and 92.6% (95% CI 89.8 to 95.4) in non-ATO groups (P = 0.066). Concerning secondary end points, the 7-y cumulative incidence of relapse (CIR) was significantly lower in ATO (2.2% [95% CI 1.1 to 4.2]) than in non-ATO group (6.1% [95% CI 3.9 to 9.5], P = 0.011). In addition, grade 3 to 4 hematological toxicities were significantly reduced in the ATO group during consolidation. Hence, ATRA-ATO in both chemotherapy-replacing and -reducing settings in consolidation is not inferior to ATRA-chemotherapy (https://www.clinicaltrials.gov/, NCT01987297).

Comparative analysis of immunological changes following realgar and arsenic trioxide treatments in a murine model of myelodysplastic syndrome.

BACKGROUND: Myelodysplastic syndrome (MDS) is a prevalent hematological neoplastic disorder in clinics and its immunopathogenesis has garnered growing interest. Oral and intravenous arsenic agents have long been used to treat hematological malignancies. The main component of oral arsenic is realgar (arsenic disulfide), while arsenic trioxide is the main component of intravenous arsenic. METHODS: This study aimed to assess the effects of ATO and Realgar on the enhancement of peripheral blood, drug safety, and T cell immune status in the NUP98-HOXD13 (NHD13) mice model of MDS, specifically in the peripheral blood, spleen, and liver. RESULTS: The study findings indicate that realgar and arsenic trioxide (ATO) can improve peripheral hemogram in mice, whereas realgar promotes higher peripheral blood cell production than ATO. Furthermore, the clinical administration method and dose did not cause significant toxicity or side effects and thus can be considered safe. Coexistence and interconversion of hyperimmune function and immunosuppression in mice were also observed in this study. In addition, there were interactions between immune cells in the peripheral blood, spleen, and liver to regulate the immune balance of the body and activate immunity via T-cell activation. CONCLUSION: In summary, oral and intravenous arsenic agents are beneficial in improving peripheral hemogram and immunity in mice.

Arsenic Trioxide Decreases Lymphangiogenesis by Inducing Apoptotic Pathways and Inhibition of Important Endothelial Cell Receptors.

Tumor-induced lymphangiogenesis is strongly associated with the formation of tumor metastasis. Therefore, the regulation of lymphangiogenesis offers a promising target in cancer therapy. Arsenic trioxide (ATO) is highly effective in the treatment of patients with acute promyelocytic leukemia (APL). As ATO mediates anti-angiogenic effects on endothelial and tumor cells, we aimed to explore the impact of ATO on lymphangiogenesis in human lymphatic endothelial cells (LEC). The BrdU assay and flow cytometry analysis were used to evaluate the influence of ATO on the proliferation and cell cycle distribution of LECs. The lymphatic suppression effects of ATO were investigated in vitro using the lymphatic tube formation assay. The effects of ATO on apoptosis, mitochondrial membrane potential and endothelial cell receptors were investigated by Western blotting, ELISA, flow cytometry and qRT-PCR. The treatment of LECs with ATO attenuated cell proliferation, blocked tube formation and induced subG0/G1 arrest in LECs, thus suggesting enhanced apoptosis. Although subG0/G1 arrest was accompanied by the upregulation of p21 and p53, ATO treatment did not lead to visible cell cycle arrest in LECs. In addition, ATO caused apoptosis via the release of cytochrome c from mitochondria, activating caspases 3, 8 and 9; downregulating the anti-apoptotic proteins survivin, XIAP and cIAP-2; and upregulating the pro-apoptotic protein Fas. Furthermore, we observed that ATO inhibited the VEGF-induced proliferation of LECs, indicating that pro-survival VEGF/VEGFR signaling was affected by ATO treatment. Finally, we found that ATO inhibited the expression of the important endothelial cell receptors VEGFR-2, VEGFR-3, Tie-2 and Lyve-1. In conclusion, we demonstrate that ATO inhibits lymphangiogenesis by activating apoptotic pathways and inhibiting important endothelial cell receptors, which suggests that this drug should be further evaluated in the treatment of tumor-associated lymphangiogenesis.

Long-term real-world outcomes of patients with acute promyelocytic leukaemia treated with arsenic trioxide and all-trans retinoic acid without chemotherapy-a retrospective, single-centre study.

Arsenic trioxide (ATO) and all-trans retinoic acid (ATRA) form the backbone of the treatment of acute promyelocytic leukaemia (APL), with the addition of chemotherapy for high-risk patients. We describe our experience of treating patients with APL of all risk classes with ATO and ATRA without chemotherapeutic agents. Patients received induction with ATO and ATRA followed by three cycles of consolidation with ATO and ATRA (each 1 month apart) after achieving morphological remission. Patients with intermediate- and high-risk disease received a further 2 years of maintenance with ATRA, 6-mercaptopurine and methotrexate. A total of 206 patients were included in the study. The majority of the patients were intermediate risk (51.9%), followed by high risk (43.2%). Differentiation syndrome was seen in 41 patients (19.9%). Overall, 25 patients (12.1%) died within 7 days of initiating therapy. Seven patients relapsed during follow-up. The mean (SD) estimated 5-year event-free survival (EFS) and overall survival (OS) in the entire cohort was 79% [5.8%] and 80% [5.8%] respectively. After excluding patients who died within 7 days of therapy initiation, the mean (SD) estimated 5-year EFS and OS was 90% [5.8%] and 93% [3.9%] respectively. Our study shows that treatment of all risk classes of APL with ATO and ATRA without chemotherapy is associated with excellent long-term outcomes in the real-world setting.

Induction of filamin-C and its involvement in the regulation of cellular senescence and apoptosis in Huh-7 hepatoma cells during arsenic trioxide exposure.

Arsenic trioxide (ATO) is one of the most toxic inorganic arsenic compounds. In this study, we examined the effects of long-term (7 days) exposure to low dose (5 µM) ATO on a human hepatocellular carcinoma cell line, Huh-7. Along with apoptosis accompanied by secondary necrosis though GSDME cleavage, we observed enlarged and flattened cells adhering to the culture dish and surviving even after exposure to ATO. An increase in cyclin-dependent kinase inhibitor p21 levels as well as positive staining for senescence-associated ß-galactosidase activity were observed in ATO-treated cells, indicating cellular senescence. Screening for both ATO-inducible proteins by MALDI-TOF-MS analysis and ATO-inducible genes by DNA microarray analysis showed a marked increase in filamin-C (FLNC), an actin cross-linking protein. Interestingly, the increase in FLNC was observed in both dead and surviving cells, suggesting that the upregulation of FLNC by ATO occurs in both apoptotic and senescent cells. Small interference RNA-mediated knock down of FLNC resulted in not only a reduction of senescence-associated enlarged morphology of the cells, but also an exacerbation of cell death. Taken together, these results suggest a regulatory role of FLNC in the execution of senescence as well as apoptosis during ATO exposure.

The involvement and therapeutic potential of lncRNA Kcnq1ot1/miR-34a-5p/Sirt1 pathway in arsenic trioxide-induced cardiotoxicity.

BACKGROUND/AIMS: Arsenic trioxide (ATO) is the first-line therapeutic drug for acute promyelocytic leukemia. However, the cardiotoxicity of ATO limits its clinical application. This study aims to explore the long noncoding RNA (lncRNA) involved molecular mechanism in ATO-induced cardiotoxicity and to identify available prevention strategies. METHODS: ATO was administered to mice or primary cultured mouse cardiomyocytes. Small interfering RNA targeting lncRNA Kcnq1ot1 (si-Kcnq1ot1) was used to knockdown lncRNA Kcnq1ot1. MiR-34a-5p mimic and antisense morpholino oligonucleotide targeting miR-34a-5p (AMO-34a-5p) were used to upregulate and downregulate the expression of miR-34a-5p, respectively. TUNEL staining was conducted to detect cell DNA damage. Flow cytometry assay was used to detect cell apoptosis. Western blot was conducted to detect Bcl-2, Bax and Sirt1 protein expression. Real-time PCR was used to detect lncRNA Kcnq1ot1, miR-34a-5p, and Sirt1 mRNA expression. Dual-luciferase reporter assay was performed to validate the predicted binding site. RESULTS: ATO induced apoptosis in cardiomyocytes both in vivo and in vitro. Simultaneously, the expression of lncRNA Kcnq1ot1 and Sirt1 was downregulated, and miR-34a-5p was upregulated. MiR-34a-5p has binding sites with lncRNA Kcnq1ot1 and Sirt1. Knockdown of lncRNA Kcnq1ot1 induced apoptosis of cardiomyocytes, with increased miR-34a-5p and decreased Sirt1 expression. Inhibition of miR-34a-5p attenuated si-Kcnq1ot1-induced apoptosis in cardiomyocytes. Therefore, the lncRNA Kcnq1ot1/miR-34a-5p/Sirt1 signaling pathway is involved in ATO-induced cardiotoxicity. Propranolol alleviated ATO-induced apoptosis in cardiomyocytes both in vivo and in vitro, which was related to the lncRNA Kcnq1ot1/miR-34a-5p/Sirt1 signaling pathway. CONCLUSION: The lncRNA Kcnq1ot1/miR-34a-5p/Sirt1 pathway is involved in ATO-induced cardiotoxicity. Propranolol can attenuate ATO-induced cardiotoxicity at least partially through the lncRNA Kcnq1ot1/miR-34a-5p/Sirt1 pathway. Combined administration with propranolol may be a new strategy for alleviating the cardiotoxicity of ATO.

Acute promyelocytic leukaemia: population-based study of epidemiology and outcome with ATRA and oral-ATO from 1991 to 2021.

BACKGROUND: The epidemiology and treatment of acute promyelocytic leukaemia (APL) are changing. We have incorporated oral arsenic trioxide (oral-ATO) into induction/maintenance. METHODS: Newly-diagnosed APL from 1991 to 2021 divided into three 10-year periods were studied to define its epidemiology and how oral-ATO impacted on its outcome. Primary endpoints included APL incidence, early deaths (ED, first 30 days), and overall survival (OS). Secondary endpoints included post-30-day OS, relapse-free survival (RFS), and incidence of second cancers. RESULTS: APL occurred in 374 males and 387 females at a median age of 44 (1-97) years. Annual incidences increased progressively, averaging 0.32 per 100,000 people. All-trans retinoic acid (ATRA)-based and oral-ATO-based regimens were used in 469 and 282 patients. There were 144 EDs, occurring almost exclusively in ATRA-based inductions (N = 139), being more with males, age > 50 years, leucocyte > 10 × 109/L, diagnosis during 1991-2009 and fewer with oral-ATO-based regimens. After a median of 75 (interquartile range: 14-161) months, 5-year and 10-year OS were 68.1% and 63.3%, inferior with males, age > 50 years, leucocyte > 10 × 109/L, high-risk Sanz score and superior with oral-ATO-based regimens. Factoring out EDs, 5-year and 10-year post-30-day OS were 84.0% and 78.1%, inferior with males and superior with oral-ATO-based regimens. In 607 CR1 patients, the 5-year RFS was 83.8%, superior with diagnosis in 2010-2021 and oral-ATO-based regimens. Second cancers developed in 21 patients, unrelated to oral-ATO-based regimens. CONCLUSIONS: There was an increasing incidence of APL, and all survivals were superior with the use of oral-ATO-based regimens. This study formed part of the Acute Promyelocytic Leukaemia Asian Consortium Project (ClinicalTrials.gov identifier: NCT04251754).

miR-603 promotes cell proliferation and differentiation by targeting TrkB in acute promyelocytic leukemia.

Arsenic trioxide (ATO) treatment effectively prolongs the overall survival of patients with acute promyelocytic leukemia (APL). Mutations in the oncogene PML::RARA were found in patients with ATO-resistant and relapsed APL. However, some relapsed patients do not have such mutations. Here, we performed microarray analysis of samples from newly diagnosed and relapsed APL, and found different microRNA (miRNA) expression patterns between these two groups. Among the differentially expressed miRNAs, miR-603 was expressed at the lowest level in relapsed patients. The expression of miR-603 and its predicted target tropomyosin-related kinase B (TrkB) were determined by PCR and Western blot. Proliferation was measured using an MTT assay, while apoptosis, cell cycle and CD11b expression were analyzed using flow cytometry. In APL patients, the expression of miR-603 was negatively correlated with that of TrkB. miR-603 directly targeted TrkB and downregulated TrkB expression in the APL cell line NB4. miR-603 increased cell proliferation by promoting the differentiation and inhibiting the apoptosis of NB4 cells. This study shows that the miR-603/ TrkB axis may be a potent therapeutic target for relapsed APL.

Andrographolide protects against doxorubicin-and arsenic trioxide-induced toxicity in cardiomyocytes.

BACKGROUND: Andrographolide (AG) is a lactone diterpene with valuable biological activities. This in vitro study evaluated whether AG can protect cardiomyocytes under toxicities triggered with anti-cancer chemotherapeutic agents, doxorubicin (DOX) and arsenic trioxide (ATO). METHODS AND RESULTS: H9C2 cells were pretreated with AG (0.5-10 µM) for 24 h and then exposed to DOX (1 µM) or ATO (35 µM) for another 24 h period. For determination of cell viability or cytotoxicity, MTT and lactate dehydrogenase (LDH) assay were used. Total oxidant and antioxidant capacities were estimated by determining hydroperoxides and ferric reducing antioxidant power (FRAP) levels. Real time-polymerase chain reaction was also used for quantitative evaluation of TLR4 gene expression. AG inhibited cardiomyocytes proliferation at the concentrations of more than 20 µM. However, it considerably enhanced cell viability and decreased cytotoxicity of DOX and ATO at the concentration range of 2.5-10 µM in MTT and LDH assays. AG significantly declined hydroperoxides concentration in ATO-treated cardiomyocytes and raised FRAP value in DOX- and ATO-treated cells. Furthermore, AG notably lessened TLR4 expression in H9C2 cells after exposure to DOX- and ATO. CONCLUSION: In conclusion, these data presented that AG was able to reverse DOX- and ATO-induced cardiotoxicity in vitro. The cardiomyocyte protective activities of AG may be due to the decrease in TLR4 expression and total oxidant capacity and increase in total antioxidant capacity.

Identification of eIF6 as a prognostic factor that drives tumor progression and predicts arsenic trioxide efficacy in lung adenocarcinoma.

BACKGROUND: Lung cancer is the leading cause of cancer-related mortality worldwide. Dysregulation of mRNA translation can contribute to the development and progression of cancer whilst also having an impact on the prognosis of different types of malignancies. Eukaryotic translation initiation factors (eIFs) have been reported to serve a key role in the initiation of mRNA translation. However, little was known about the association between eIF6 and lung adenocarcinoma (LUAD) progression. We aimed to elucidate the roles of eIF6 in LUAD tumorigenesis. METHODS: Bioinformatic analysis was conducted to assess the clinical significance of eIF6 in LUAD. CCK-8, colony formation assays were used to evaluate the biological roles of eIF6. The subcutaneous model was used to assess the in vivo roles of eIF6. RESULTS: In the present study, it was found that eIF6 expression was significantly higher in LUAD samples compared with that in normal lung tissues. Higher expression levels of eIF6 were found to be associated with more advanced clinical stages of LUAD and poorer prognoses in patients with LUAD. Subsequently, overexpression of eIF6 was demonstrated to promote LUAD cell proliferation, migration and invasion, which are features of metastasis, in vitro. By contrast, inhibition of eIF6 induced cell cycle arrest and apoptosis in LUAD cells. Further bioinformatics analysis and experimental assays revealed that eIF6 expression positively correlated with the mRNA expression of stemness-associated genes in LUAD cells. Targeting eIF6 suppressed the sphere formation capacity of LUAD cells. In addition, data from the subcutaneous xenograft model in vivo also suggested that eIF6 deficiency could significantly delay tumor growth and improve the prognosis of mice. Targeting eIF6 rendered LUAD cells sensitive to arsenic trioxide treatment. CONCLUSION: The present study suggest that eIF6 can serve as a prognostic biomarker and a potential therapeutic target for patients with LUAD.

Arsenic trioxide and Erlotinib loaded in RGD-modified nanoliposomes for targeted combination delivery to PC3 and PANC-1 cell lines.

During the past few years, advances in drag delivery have provided many opportunities in the treatment of various diseases and cancer. Arsenic trioxide (ATO) and Erlotinib (Erlo) are two drugs, approved by the United States Food and Drug Administration to treat cancer, but their use is limited in terms of the toxicity of ATO and the low solubility of Erlo. This study aimed to prepare arginine-glycine-aspartic acid (RGD)-decorated nanoliposomes (NLPs) containing Erlo and ATO (NLPs-ATO-Erlo-RGD) to increase the solubility and reduce the toxicity of Erlo and ATO for cancer treatment. The results of transmission electron microscopy and dynamic light scattering showed that NLPs were synthesized uniformly, with spherical shape morphology and particle sizes between 140 and 160 nm. High-performance liquid chromatography and ICP-MS results showed that about 90% of the drug was loaded in the NLPs. In comparison with NLPs-ATO-Erlo, NLPs-ATO-Erlo-RGD demonstrated considerable toxicity against the αvß3 overexpressing PC3 cell line in the MTT experiment. It had no effect on the PANC-1 cell line. In addition, apoptosis assays using Annexin V/PI demonstrated that NLPs-ATO-Erlo-RGD generated the highest apoptotic rates in PC3 cells when compared with NLPs-ATO-Erlo and the combination of free ATO and Erlo. Furthermore, treatment with NLPs-ATO-Erlo-RGD in (p < 0.05) PC3 cell line significantly reduced EGFR level. It is concluded NLPs-ATO-Erlo-RGD as a novel drug delivery system may be a promising platform for the treatment of cancer.

Pulmonary pathogenesis in a murine model of inhaled arsenical exposure.

Arsenic trioxide (ATO), an inorganic arsenical, is a toxic environmental contaminant. It is also a widely used chemical with industrial and medicinal uses. Significant public health risk exists from its intentional or accidental exposure. The pulmonary pathology of acute high dose exposure is not well defined. We developed and characterized a murine model of a single inhaled exposure to ATO, which was evaluated 24 h post-exposure. ATO caused hypoxemia as demonstrated by arterial blood-gas measurements. ATO administration caused disruption of alveolar-capillary membrane as shown by increase in total protein and IgM in the bronchoalveolar lavage fluid (BALF) supernatant and an onset of pulmonary edema. BALF of ATO-exposed mice had increased HMGB1, a damage-associated molecular pattern (DAMP) molecule, and differential cell counts revealed increased neutrophils. BALF supernatant also showed an increase in protein levels of eotaxin/CCL-11 and MCP-3/CCL-7 and a reduction in IL-10, IL-19, IFN-γ, and IL-2. In the lung of ATO-exposed mice, increased protein levels of G-CSF, CXCL-5, and CCL-11 were noted. Increased mRNA levels of TNF-a, and CCL2 in ATO-challenged lungs further supported an inflammatory pathogenesis. Neutrophils were increased in the blood of ATO-exposed animals. Pulmonary function was also evaluated using flexiVent. Consistent with an acute lung injury phenotype, respiratory and lung elastance showed significant increase in ATO-exposed mice. PV loops showed a downward shift and a decrease in inspiratory capacity in the ATO mice. Flow-volume curves showed a decrease in FEV0.1 and FEF50. These results demonstrate that inhaled ATO leads to pulmonary damage and characteristic dysfunctions resembling ARDS in humans.

Expanding the Chemical Space of Arsenicin A-C Related Polyarsenicals and Evaluation of Some Analogs as Inhibitors of Glioblastoma Stem Cell Growth.

The marine polyarsenical metabolite arsenicin A is the landmark of a series of natural and synthetic molecules characterized by an adamantane-like tetraarsenic cage. Arsenicin A and related polyarsenicals have been evaluated for their antitumor effects in vitro and have been proven more potent than the FDA-approved arsenic trioxide. In this context, we have expanded the chemical space of polyarsenicals related to arsenicin A by synthesizing dialkyl and dimethyl thio-analogs, the latter characterized with the support of simulated NMR spectra. In addition, the new natural arsenicin D, the scarcity of which in the Echinochalina bargibanti extract had previously limited its full structural characterization, has been identified by synthesis. The dialkyl analogs, which present the adamantane-like arsenicin A cage substituted with either two methyl, ethyl, or propyl chains, were efficiently and selectively produced and evaluated for their activity on glioblastoma stem cells (GSCs), a promising therapeutic target in glioblastoma treatment. These compounds inhibited the growth of nine GSC lines more potently than arsenic trioxide, with GI50 values in the submicromolar range, both under normoxic and hypoxic conditions, and presented high selectivity toward non-tumor cell lines. The diethyl and dipropyl analogs, which present favorable physical-chemical and ADME parameters, had the most promising results.

Arsenic trioxide liposome gels for the treatment of psoriasis in mice.

Psoriasis is a chronic, immune-mediated skin disease with no cure. Intravenous arsenic trioxide (ATO) has been used to treat psoriasis in animal studies. However, the high toxicity of ATO limits its application to clinics for systemic administration. The aim of this study was to fabricate sustained-release ATO liposome gels (ATO-Lip-Gels) to be used for the treatment of psoriasis. The ATO Liposomes were prepared using a zinc acetate gradient method. ATO concentrations were analyzed by HPLC-HG-AFS. The ATO-Lip-Gels were characterized with respect to size, zeta potential, and entrapment efficiency. Stability, in vitro drug release, and in vivo efficacy were also evaluated. The optimal formulation of ATO-Lip was ATO (0.45%), S100 (9%), and cholesterol (1.5%) (W/V) in 0.3 mol/L zinc acetate and incubated for 10 min. In the in vitro drug release study, ATO-Lip-Gels exhibited a slower release profile of ATO than that from Gels only. Compared with the model group, ATO-Lip-Gels-H significantly reduced PASI scores after psoriasis in mice and was superior to tacrolimus at day 5. HE staining showed that the pathological changes caused by psoriasis in mice were significantly improved in the treatment groups, and ATO-Lip-Gels-H had the best effect among the treatment groups. ATO-Lip-Gels applied topologically to imiquimote-induced psoriatic plaque models significantly reduced the levels of key psoriatic cytokines such as IL-6 and TNF-α. We have developed ATO-Lip-Gels for the treatment of psoriasis, which demonstrated higher efficacy with the benchmark, Tacrolimus, and can be an alternative to the conventional treatment with Tacrolimus.