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.

International review of blood donation nucleic acid amplification testing.

BACKGROUND AND OBJECTIVES: Nucleic acid amplification testing (NAT), in blood services context, is used for the detection of viral and parasite nucleic acids to reduce transfusion-transmitted infections. This project reviewed NAT for screening blood donations globally. MATERIALS AND METHODS: A survey on NAT usage, developed by the International Society of Blood Transfusion Working Party on Transfusion-transmitted Infectious Diseases (ISBT WP-TTID), was distributed through ISBT WP-TTID members. Data were analysed using descriptive statistics. RESULTS: Forty-three responses were received from 32 countries. Increased adoption of blood donation viral screening by NAT was observed over the past decade. NAT-positive donations were detected for all viruses tested in 2019 (proportion of donations positive by NAT were 0.0099% for human immunodeficiency virus [HIV], 0.0063% for hepatitis C virus [HCV], 0.0247% for hepatitis B virus [HBV], 0.0323% for hepatitis E virus [HEV], 0.0014% for West Nile virus [WNV] and 0.00005% for Zika virus [ZIKV]). Globally, over 3100 NAT-positive donations were identified as NAT yield or solely by NAT in 2019 and over 22,000 since the introduction of NAT, with HBV accounting for over half. NAT-positivity rate was higher in first-time donors for all viruses tested except WNV. During 2019, a small number of participants performed NAT for parasites (Trypanosoma cruzi, Babesia spp., Plasmodium spp.). CONCLUSION: This survey captures current use of blood donation NAT globally. There has been increased NAT usage over the last decade. It is clear that NAT contributes to improving blood transfusion safety globally; however, there is a need to overcome economic barriers for regions/countries not performing NAT.

Cytokine-Induced Memory-Like NK Cells: Emerging strategy for AML immunotherapy.

Acute myeloid leukemia (AML) is a heterogeneous disease developed from the malignant expansion of myeloid precursor cells in the bone marrow and peripheral blood. The implementation of intensive chemotherapy and hematopoietic stem cell transplantation (HSCT) has improved outcomes associated with AML, but relapse, along with suboptimal outcomes, is still a common scenario. In the past few years, exploring new therapeutic strategies to optimize treatment outcomes has occurred rapidly. In this regard, natural killer (NK) cell-based immunotherapy has attracted clinical interest due to its critical role in immunosurveillance and their capabilities to target AML blasts. NK cells are cytotoxic innate lymphoid cells that mediate anti-viral and anti-tumor responses by producing pro-inflammatory cytokines and directly inducing cytotoxicity. Although NK cells are well known as short-lived innate immune cells with non-specific responses that have limited their clinical applications, the discovery of cytokine-induced memory-like (CIML) NK cells could overcome these challenges. NK cells pre-activated with the cytokine combination IL-12/15/18 achieved a long-term life span with adaptive immunity characteristics, termed CIML-NK cells. Previous studies documented that using CIML-NK cells in cancer treatment is safe and results in promising outcomes. This review highlights the current application, challenges, and opportunities of CIML-NK cell-based therapy in AML.

Spotlight on contributory role of host immunogenetic profiling in SARS-CoV-2 infection: Susceptibility, severity, mortality, and vaccine effectiveness.

BACKGROUND: The SARS-CoV-2 virus has spread continuously worldwide, characterized by various clinical symptoms. The immune system responds to SARS-CoV-2 infection by producing Abs and secreting cytokines. Recently, numerous studies have highlighted that immunogenetic factors perform a putative role in COVID-19 pathogenesis and implicate vaccination effectiveness. AIM: This review summarizes the relevant articles and evaluates the significance of mutation and polymorphism in immune-related genes regarding susceptibility, severity, mortality, and vaccination effectiveness of COVID-19. Furthermore, the correlation between host immunogenetic and SARS-CoV-2 reinfection is discussed. METHOD: A comprehensive search was conducted to identify relevant articles using five databases until January 2023, which resulted in 105 total articles. KEY FINDINGS: Taken to gather this review summarized that: (a) there is a plausible correlation between immune-related genes and COVID-19 outcomes, (b) the HLAs, cytokines, chemokines, and other immune-related genes expression profiles can be a prognostic factor in COVID-19-infected patients, and (c) polymorphisms in immune-related genes have been associated with the effectiveness of vaccination. SIGNIFICANCE: Regarding the importance of mutation and polymorphisms in immune-related genes in COVID-19 outcomes, modulating candidate genes is expected to help clinical decisions, patient outcomes management, and innovative therapeutic approach development. In addition, the manipulation of host immunogenetics is hypothesized to induce more robust cellular and humoral immune responses, effectively increase the efficacy of vaccines, and subsequently reduce the incidence rates of reinfection-associated COVID-19.

Therapeutic approaches for relapsed/refractory adult acute lymphoblastic leukemia (ALL), a review on monoclonal antibodies and targeted therapies.

Acute lymphoblastic leukemia (ALL) is the malignant transformation of lymphoid progenitors that affects both children and adults. Although the outcome of pediatric patients has been improved dramatically, there are still many challenges in the treatment of adults. Patients with primary resistant or relapsed disease have the worst outcome and despite the administration of intensified multi-agents chemotherapies, the outcome of this group remains very poor. Accordingly, the development of novel therapeutic options is considered necessary. Having a comprehensive insight into the pathophysiology of ALL and aberrant signaling pathways is crucial for introducing effective targeted therapies. Combination therapies with new drugs and innovative targeted therapies with the aim of affecting the main aberrant signaling pathways in the disease are considered as new approaches. Here we tried to have a comprehensive review on the potential molecular targets in the treatment of refractory/relapsed ALL and the current therapeutic agents.

The Roles of Exosomal microRNAs in Diffuse Large B-Cell Lymphoma: Diagnosis, Prognosis, Clinical Application, and Biomolecular Mechanisms.

Background: Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous neoplasm and is characterized as the most common subtype of non-Hodgkin lymphoma (NHL). Despite 60-70% of all patients being cured with R-CHOP therapeutic regimen (Cyclophosphamide, doxorubicin, vincristine, and prednisone, combined with rituximab), remaining patients display aggressive disease. Therefore, there is an urgent need to develop novel diagnostic, prognostic, and predictive biomarkers. Recently, exosomal miRNAs have been approved as novel biomarkers in DLBCL due to their potential involvement in lymphomagenesis. Material and Methods: We conducted an investigation on the potential role of exosomal miRNAs as diagnostic, prognostic, and predictive biomarkers in DLBCL in the PubMed, Scopus, and Web of Science search engines. We searched by using a combination of keywords, such as diffuse large B-cell lymphoma, DLBCL, miRNA, microRNA, miR, exosome, exosomes, exosomal, extracellular vesicles, EVs, and secretome. Then, search results were narrowed based on specific inclusion and exclusion criteria. Results: Twelve articles were eligible for our systematic reviews. Among them, nine discussed diagnostic biomarkers, three considered prognostic significance, four evaluated therapeutic efficacy, two studies were conducted in vitro, and three assessed molecular pathways associated with these exosomal miRNAs in DLBCL. Discussion: According to our systematic review, exosomal miRNAs are not only useful for diagnosis and prognosis in DLBCL but are also promising therapeutic tools and predictors of response to therapy. Although promising results so far, more research is required to develop innovative biomarkers.

A comparative study of pathogen inactivation technologies in human platelet lysate and its optimal efficiency in human placenta-derived stem cells culture.

BACKGROUND: Pathogen inactivation (PI) is necessary for the pooled components derived from a biological source. Recently, the use of human platelet lysate (hPL) has increased in the cell manufacturing process as a xeno-free substitute for Fetal Bovine Serum (FBS). Therefore, an effective PI process to produce a pathogen-free hPL with the optimal efficiency in the manufacturing of cell therapy products is a vital requirement. STUDY DESIGN AND METHODS: To evaluate the efficacy of gamma irradiation and riboflavin/ultraviolet light (RB/UV) as PI methods for hPL, the reduction factor (RF) of titer of model viruses and bacteria were examined. Furthermore, the effect of different PI methods on the hPL performance was evaluated by the in vitro expansion of human placenta-derived mesenchymal stem cells (PLMSCs). To compare different study groups, the growth kinetic, immunophenotype, colony formation, and differentiation capacity (osteogenic and adipogenic) of PLMSCs were examined. In addition, the concentration of growth factors was assayed in each study group. RESULTS: Achievement to the RF more than 5 log10 for all pathogens, showed the effectiveness of two PI methods. In comparison with the other study groups, the dose of 45 kGy gamma irradiation considerably decreased the growth factor level of the hPL. It also showed a significant adverse effect on PLMSCs growth kinetics. The dose of 30 KGy gamma irradiation and RB/UV demonstrated a favorable effect on different assays of the in vitro expanded PLMSCs. CONCLUSION: The 30 KGy gamma irradiation and RB/UV were effective in the RF of the viral and bacterial models of the contaminated hPL. The efficacy of these PI-hPLs for PLMSCs expansion was preserved. To increase the safety of cell therapy products, PI methods should be considered for the hPL preparations.

Britannin a Sesquiterpene Lactone from Inula aucheriana Exerted an Anti-leukemic Effect in Acute Lymphoblastic Leukemia (ALL) Cells and Enhanced the Sensitivity of the Cells to Vincristine.

Since chemotherapy drugs have dose-related side effects, there is still a need for finding new agents with suitable cytotoxic effects without any harmful effects. For this purpose, we evaluated the cytotoxic effects of Britannin that is a Sesquiterpene Lactone compound Inula aucheriana, alone or in combination with Vincristine (VCR), on Acute Lymphoblastic Leukemia (ALL)-derived MOLT-4 cells. In this study, we found that Britannin decreased the viability of MOLT-4 cells with the IC50 Values of 2 µM, but had no cytotoxic effects on normal cells or Peripheral Blood Mononuclear Cells (PBMCs). Our results also showed that Britannin decreased the proliferation of MOLT-4 cells by preventing the transition of the cells from the S phase of the cell cycle through the up-regulation of p21 and p27. Moreover, this agent induced ROS-mediated apoptosis by altering the expression of Bax, Bim, Caspase3, Bcl2, and XIAP. Britannin also produced a synergistic effect with Vincristine in MOLT-4 cells. Taken together, the results of this study showed for the first time that Britannin, as a natural Sesquiterpene Lactone, has cytotoxic effects that could be considered as an anti-leukemic agent in the treatment of ALL. However, there is still a demand for further studies that examine the efficacy and the safety of this purified compound.

Extracellular Vesicles in Acute Leukemia: A Mesmerizing Journey With a Focus on Transferred microRNAs.

Despite their small size, the membrane-bound particles named extracellular vesicles (EVs) seem to play an enormous role in the pathogenesis of acute leukemia. From oncogenic hematopoietic stem cells (HSCs) to become leukemic cells to alter the architecture of bone marrow (BM) microenvironment, EVs are critical components of leukemia development. As a carrier of essential molecules, especially a group of small non-coding RNAs known as miRNA, recently, EVs have attracted tremendous attention as a prognostic factor. Given the importance of miRNAs in the early stages of leukemogenesis and also their critical parts in the development of drug-resistant phenotype, it seems that the importance of EVs in the development of leukemia is more than what is expected. To be familiar with the clinical value of leukemia-derived EVs, this review aimed to briefly shed light on the biology of EVs and to discuss the role of EV-derived miRNAs in the development of acute myeloid leukemia and acute lymphoblastic leukemia. By elaborating the advances and challenges concerning the isolation of EVs, we discuss whether EVs could have a prognostic value in the clinical setting for leukemia.

Britannin, a sesquiterpene lactone induces ROS-dependent apoptosis in NALM-6, REH, and JURKAT cell lines and produces a synergistic effect with vincristine.

BACKGROUND: Britannin, a Sesquiterpene Lactone isolated from Inula aucheriana, has recently gained attraction in the therapeutic fields due to its anti-tumor properties. This study was designed to evaluate the effect of this agent on Acute Lymphoblastic Leukemia (ALL) cell lines, either as a monotherapy or in combination with Vincristine (VCR). METHODS AND RESULTS: To determine the anti-leukemic effects of Britannin on ALL-derived cell lines and suggest a mechanism of action for the agent, we used MTT assay, Annexin-V/PI staining, ROS assay, and real-time PCR analysis. Moreover, by using a combination index (CI), we evaluated the synergistic effect of Britannin on Vincristine. We found that unlike normal Peripheral Blood Mononuclear Cells (PBMCs) and L929 cells, Britannin reduced the viability of NALM-6, REH, and JURKAT cells. Among tested cells, NALM-6 cells had the highest sensitivity to Britannin, and this agent was able to induce p21/p27-mediated G1 cell cycle arrest and Reactive Oxygen Specious (ROS)-mediated apoptotic cell death in this cell line. When NALM-6 cells were treated with Nacetyl-L-Cysteine (NAC), a scavenger of ROS, Britannin could induce neither apoptosis nor reduce the survival of the cells suggesting that the cytotoxic effect of Britannin is induced through ROS-dependent manner. Moreover, we found that a low dose of Britannin enhanced the effect of Vincristine in NALM-6 cells by inducing apoptotic cell death via altering the expression of apoptotic-related genes. CONCLUSIONS: Overall, our results proposed a mechanism for the cytotoxic effect of Britannin, either as a single agent or in combination with Vincristine, in NALM-6 cells.

IFNG-AS1 and MAF4 long non-coding RNAs are upregulated in acute leukemia patients who underwent bone marrow transplantation.

PURPOSE OF THE STUDY: Acute graft versus host disease (aGVHD) is an immune-mediated reaction that results in impaired immune and body function after allogeneic hematopoietic stem cell transplantation (allo-HSCT). lncRNAs have been discovered as particular T cell regulators, and alloreactive T cells have been known as a critical factor in aGVHD. As a result, we investigated the importance of lnc-MAF4 and IFNG-AS1 expression levels in aGVHD patients versus non-aGVHD patients. MATERIAL AND METHODS: This research included 38 patients with hematological disorders who were undergoing primary allo-HSCT. Human identical siblings or unrelated donors were used to collect stem cell. Samples were taken within days 0, 7, 14, 28, and 52±8 after transplantation. The expression of lncRNA levels was measured using the QRT-PCR technique. And the data were analyzed using GraphPad Prism 6 RESULTS: Our data revealed that LncRNA MAF4 and INFG-AS1 expression levels in aGVHD were not significantly different compared to the non-GVHD group immediately after transplantation, nor at day 7 or 14. However, the aGVHD group showed an overt up-regulation of the two lncRNAs on samples taken at day 28 and 52±8 compared to non-GVHD patients. DISCUSSION: Since the intracellular pathway of these lncRNAs shows a direct relationship with the IFNγ cytokine production resulting in differentiation to TH1 cells and inhibition of differentiation to TH2 cells, they can be, therefore, considered as suitable molecular candidates for the prediction of aGVHD in patients receiving HSCT.

Assessment the knowledge of blood transfusion in Iranian nurses of Tehran's hospitals.

OBJECTIVE: To investigate the knowledge of nurses about pre and post blood transfusion processes. BACKGROUND: To ensure a safe blood transfusion, apart from the role of blood banking to perform safe donation, attention must be paid to equally important but rather neglected factors including nursing practice and knowledge of blood transfusion. METHOD AND MATERIALS: Data was collected using a valid blood transfusion questionnaire consisting of 43 questions. We analysed data using SPSS 22. Percentages and analytical statistics such as Mann-Whitney, Kruskal-Wallis were used to report the results. The significant level of p-value was assumed to be <0.05. RESULTS: In this study, 325 nurses participated and their knowledge scores ranged from 24% to 85% (mean 56.16, standard deviation: 5.92) and the majority of nurses lacked knowledge in pre-transfusion activities. The analysis also revealed there was a significant correlation between the knowledge score and academic degree. Out of all nurses, 48% (N = 156) declared that they need further training in haemovigilance. As the minimum and maximum scored questions, it was revealed that only 39 nurses (12%) have enough knowledge to act properly in case of ambiguous orders; on the other hand, 94% (N = 304) have sufficient knowledge of the agents administered with transfusion. A large proportion of the involved nurses are unaware of the risk of improper identification. CONCLUSION: All the efforts taken to prepare a safe and matched blood unit would be futile by inattentive administration of blood. That is why mandatory ongoing blood transfusion training for nurses is required urgently.

Circulatory miR-155 correlation with platelet and neutrophil recovery after autologous hematopoietic stem cell transplantation, a multivariate analysis.

The involvement of microRNAs in the regulation of hematopoietic stem cells paves the way for their use in the management of autologous HSC transplantation (AHSCT). We aimed to evaluate the predictive value of circulatory microRNAs in extracellular vesicles (EVs) and plasma in platelet and neutrophil engraftment. Circulatory miR-125b, mir-126, miR-150, and miR-155 expression was assessed in isolated EVs and plasma in samples collected from AHSCT candidates. Multivariate analysis, COX models, and ROC assessment were performed to evaluate the predictive values of these microRNAs in platelet and neutrophil engraftment. miR-155 expression following conditioning with other clinical factors such as chemotherapy courses after diagnosis was the most significant predictors of platelet/neutrophil engraftment. A CD34+ cell count ≥ 3.5 × 106/kg combined with miR-155 could be used as an engraftment predictor; however, in cases where the CD34+ cell count was < 3.5 × 106/kg, this parameter lost its predictive value for engraftment and could be replaced by miR-155. The correlation between miR-155 and platelet/neutrophil engraftment even with lower numbers of CD34+ cells suggests the importance of this microRNA in the prediction of AHSCT outcome. Moreover, miR-155 could be utilized in therapeutic approaches to provide a better outcome for patients undergoing AHSCT.

Stimulation of Peroxisome Proliferator-Activated Receptor-Gamma (PPARγ) using Pioglitazone Decreases the Survival of Acute Promyelocytic Leukemia Cells through Up-Regulation of PTEN Expression.

BACKGROUND: The intertwining between cancer pathogenesis and aberrant expression of either oncogenes or tumor suppressor proteins ushered the cancer therapeutic approaches into a limitless road of modern therapies. For the nonce and among the plethora of promising anticancer agents, intense interest has focused on pioglitazone, a first in-class of Thiazolidinedione (TZD) drugs that is currently used to treat patients with diabetes. OBJECTIVE: Intrigued by the overexpression of PPARγ in Acute Promylocytic Leukemia (APL), this study was designed to investigate the effects of pioglitazone in APL-derived NB4 cells. METHODS: To assess the anti-leukemic effect of pioglitazone on myeloid leukemia cell lines, we used MTT and trypan blue assays. Given the higher expression level of PPARγ in NB4 cells, we then expanded our experiments on this cell line. To ascertain the molecular mechanism action of pioglitazone in APL-derived NB4 cells, we evaluated the expression levels of a large cohort of target genes responsible for the regulation of apoptosis, autophagy and cell proliferation. Afterward, to examine whether there is a correlation between PPARγ and the PI3K signaling pathway, the amount of Akt phosphorylation was evaluated using western blot analysis. RESULTS: Our results showed that pioglitazone exerted its cytotoxic effect in wild-type PTEN-expressing NB4 cells, but not in leukemic K562 cells harboring mutant PTEN; suggesting that probably this member of TZD drugs induced its anti-leukemic effects through a PTEN-mediated manner. Moreover, we found that not only pioglitazone reduced the survival rate of NB4 through the induction of p21-mediated G1 arrest, also elevated the intracellular level of Reactive Oxygen Species (ROS) which was coupled with upregulated FOXO3a. Notably, this study proposed for the first time that the stimulation of autophagy as a result of the compensatory activation of PI3K pathway may act as a plausible mechanism through which the anti-leukemic effect of pioglitazone may be attenuated; suggestive of the application of either PI3K or autophagy inhibitors along with pioglitazone in APL. CONCLUSION: By suggesting a mechanistic pathway, the results of the present study shed more light on the favorable anti-leukemic effect of pioglitazone and suggest it as a promising drug that should be clinically investigated in APL patients.

Red blood cell alloimmunization in Iran: A Comprehensive review of the literature.

BACKGROUND: Alloimmunization is an immune response against foreign antigens which introduced into the body through transfusion, pregnancy, or transplantation. This phenomenon is a big challenge in patients, which require regular transfusions. In the current study, we tried to have a comprehensive review on the status of alloimmunization in Iran. For this purpose, we searched for papers investigating alloimmunization in transfusion-dependent patients and also in patients with no regular transfusions who are candidate for surgery or who need blood. METHODS: We searched PubMed, Google Scholar, SID, and MAGIRAN databases using the following keywords: "blood transfusion," "alloimmunization," "alloantibodies," "irregular antibodies," "red cell antibodies," and "Iran." No limitation for the date of publication and language of the papers was defined. All the identified records were then screened for the relevance and duplication. RESULTS: A total of 22 papers were included in this study. All of the studies were conducted from 1999 to 2016 and providing alloimmunization data from different cities all over of Iran. In general, the results showed that the most prevalent alloantibodies are anti-Kell (anti-K antigen) and anti-Rh system, mainly anti-E, anti-D, anti-C, and anti-c. CONCLUSION: Anti-Kell and anti-Rh antibodies are the most prevalent antibodies responsible for alloimmunization in Iranian population.

Investigating the inhibitory effect of miR-34a, miR-449a, miR-1827, and miR-106b on target genes including NOTCH1, c-Myc, and CCND1 in human T cell acute lymphoblastic leukemia clinical samples and cell line.

OBJECTIVES: microRNAs are small non-coding molecules that regulate gene expression in various biological processes. T-cell acute lymphoblastic leukemia (T-ALL) is a malignancy accompanied with genetic aberrations and accounts for 20% of children's and adult's ALL. Notch signaling pathway dysregulation occurs in 60% of T-ALL cases. In the present study, we aimed to determine the relationship between miRNAs and genes involved in Notch signaling pathway. MATERIALS AND METHODS: Considering the role of the pathway and its down-stream genes in proliferation, differentiation, cell cycle, and apoptosis, NOTCH1, c-Myc, and CCND1 genes were selected as target genes. Using bioinformatics studies, miR-34a, miR-449a, miR-1827, and miR-106b were selected as miRNAs targeting the above-mentioned genes. We evaluated these genes and miRNAs in T-ALL clinical samples as well as Jurkat cell line, in which NOTCH1 is overexpressed. RESULTS: Quantitative Real-Time PCR indicated that NOTCH1, c-Myc, and CCND1 were overexpressed in samples with decreased expression of miR-34a. In addition, we observed that samples with decreased expression of miR-449a showed increased expression of NOTCH1 and CCND1. Furthermore, we analyzed the expression of miR-1827 and miR-106b, which target c-Myc and CCND1, respectively. We found out that the expression of miR-1827, miR-106b, and their respective target genes were inversely correlated in 80% and 75% of the cases (r=0.8), respectively. Furthermore, in Jurkat cell line, the expression of target genes was increased while the candidate miRNAs except miR-34a were decreased. CONCLUSION: These miRNAs can be proposed as biomarkers and new therapeutic targets in T-ALL patients who have NOTCH1 overexpression.

Activation of PPARγ intensified the effects of arsenic trioxide in acute promyelocytic leukemia through the suppression of PI3K/Akt pathway: Proposing a novel anticancer effect for pioglitazone.

The indulgent success of arsenic trioxide (ATO) in the induction of complete remission in acute promyelocytic leukemia (APL) patients has accommodated this agent into the therapeutic protocols. However, the intrusion of unfavorable side effects had put an unanswered question on the way of the application of this agent; whether the benefits of ATO may outweigh its drawbacks. In this study, we found that when ATO is accompanied by an activator of peroxisome proliferator-activated receptors gamma (PPARγ), even the lower concentrations could induce significant inhibitory effects on the survival of NB4 through diminishing the ability of the cells to replicate DNA in the S phase of cell cycle. We also found that through suppression of the PI3K pathway, the combination of pioglitazone and ATO provided a signal through which the induction of apoptotic cell death was enhanced probably via the elevation of reactive oxygen species (ROS). With respect to the tight connection between PI3K pathway and autophagy system and given to the inhibitory effect of pioglitazone-plus-ATO on PI3K, we found that the combination of these agents not only suppressed the expression of autophagy-related genes, but also their efficacy was augmented when autophagy was inhibited in NB4; clarifying the encouraging role of autophagy in the survival maintenance of APL cells. In conclusion, given the significant efficacy as well as the safety profile of pioglitazone in potentiating the anticancer effects of chemotherapeutic drugs, the present study suggests it as a promising agent to be used in adjuvant strategy for the treatment of APL.

Ergolide, a potent sesquiterpene lactone induces cell cycle arrest along with ROS-dependent apoptosis and potentiates vincristine cytotoxicity in ALL cell lines.

ETHNOPHARMACOLOGICAL RELEVANCE: Inula oculus christi belongs to the family of Asteraceae and it was traditionally wide used in treatment of kidney stones and urethra infection; besides, recently the potent sesquiterpene lactones isolated from inula species has gained increasing attention in cancer treatments. This study investigates the anti-cancer properties and underlying mechanism of ergolide isolated from Inula oculus christi against leukemic cell lines. METHODS: Viability, metabolic activity and proliferation evaluated using different index of MTT assay such as IC50 and GI50. Human erythrocytes were used to evaluate hemolytic activity. Flow-cytometry was used to detect and measure ROS level, and the induction of apoptosis and autophagy were evaluated using Annexin V/PI, Acridine Orange staining, respectively. Moreover, qRT-PCR was performed to examine the expression of a large cohort of crucial regulatory genes. Tunel assay was also carried out to assess morphologically ergolide effects. RESULTS: Ergolide did not exert ant cytotoxicity against non-tumorous cells and did not cause noticeable hemolysis. It also caused ROS production during early hours after treatment of cells which was then followed by cell cycle arrest in G0/G1 phase and autophagy induction. Using N-acetyl-L-cysteine (NAC), we found that ergolide could not increase ROS and induce autophagy and moreover repressed cell death, indicating that ergolide induce cell death through ROS-dependent manner by altering the expression of pro apoptotic related genes. Autophagy inhibition also potentiated ergolide-induced cell death. Furthermore, ergolide intensified vincristine cytotoxicity against acute lymphoblastic leukemia (ALL) cell lines revealed robust synergistic properties of ergolide with VCR. CONCLUSION: Here we showed that ergolide could be considered as a potent natural compound against leukemic cells by inducing cell cycle arrest followed by dose-dependent cell death. Based on results, Autophagy response in a result of ROS accumulation acted as a survival pathway and blocking this pathway could noticeably increase ergolide cytotoxicity on ALL cell lines.