Cytarabine Research Articles

Design, synthesis and biological evaluation of rhein-piperazine-furanone hybrids as potential anticancer agents.

Novel rhein-piperazine-furanone hybrids, 5, were designed and synthesized efficiently from rhein. Cytotoxicity of all hybrids 5a-j against A549 human lung cancer cells was superior to the parent rhein and the reference cytarabine (CAR). Hybrid 5e (IC50 = 5.74 μM), the most potent compound, was 46- and 35-fold more toxic against A549 cells than rhein (IC50 = 265.59 μM) and CAR (IC50 = 202.57 μM), respectively. Moreover, hybrid 5e (IC50 = 69.28 μM) was less toxic to normal WI-38 human lung fibroblast cells with good selectivity (WI-38/A549, SI ≈ 12), being much higher than rhein (SI ≈ 1) and CAR (SI ≈ 2). Structure-activity relationship (SAR) analysis showed that cytotoxicity and selectivity against A549 lung cancer cells were greatly enhanced when methoxy-containing furanone was introduced to the hybrids (5e and 5h). Further, hybrid 5e showed better cytotoxicity against four types of human lung cancer cells (H460, A549, PC-9, and Calu-1; IC50 = 4.35-15.39 μM) than six other types of human cancer cells (SK-BR-3, SK-OV-3, 786-O, Huh-7, HCT116, and HeLa; IC50 = 13.77-60.45 μM), showing specificity. In particular, hybrid 5e showed the highest cytotoxicity (IC50 = 4.35 μM) and the highest selectivity (WI-38/H460, SI ≈ 16) against H460 human lung cancer cells. Flow cytometric analysis showed that hybrid 5e induced apoptosis in a concentration-dependent manner in H460 cells. The results show that the cytotoxicity and selectivity of rhein can be greatly enhanced by hybridization with furanone. Hybrid 5e is expected to be a leading candidate for anti-lung cancer drugs.

Diplopia as the presenting symptom of a post‐transplant lymphoproliferative disorder in a bilateral inferior lim transplanted young adult

Aims/Purpose: To present a unique case of post‐transplant lymphoproliferative disorder (PTLD) after bilateral inferior limb transplantation, which is still controversial due to the absence of precedents in the literature and the unclear risk–benefit ratio.Methods: Case report.Results: A 22‐year‐old male presented to the emergency room complaining of double vision. He had a history of bilateral inferior limb amputation 8 years ago and received a bilateral lower limb transplantation 2 years later. He had normal graft function and was receiving cytomegalovirus prophylaxis. During neurological examinations left abducens nerve (CN VI) palsy was noted. Other cranial nerves affected produced facial hypoesthesia (CN V) and mild paresis (CN VII), hearing loss and tinnitus in left side (CN VIII) and soft palate asymmetry (CN X). He was otherwise neurologically intact, alert and orientated. MRI revealed a lesion located at the facial colliculus at the floor of 4th ventricle. In the context of immunosuppression, the differential diagnosis included abscess versus PTLD. Biopsy of the lesion was performed. Morphologically atypical lymphocytic cells suggestive of B lymphoma were identified. Monoclonal rearrangement for heavy chain Igen and immunoglobulins were identified with molecular biology techniques. The histology features were consistent with a diagnosis of CNS B lineage primary lymphoma. Two days later, bilateral supracondylar amputation was performed. Following the explant, immunosuppression was withdrawn. His underlying condition was finally diagnosed as PTLD, for which he started a chemotherapeutic regimen with radical intention (methotrexate and cytosine arabinoside). The patient recovered fully and up to date, 10 years later, is doing well.Conclusions: Due to its diverse aetiologias, a proper workup must be done of the patients presenting with diplopia to the emergency room. PLTD must be a condition to always be considered in patients with history of solid organ transplant; since the early diagnosis is crucial for a successful management of this often‐fatal condition.

Centrilobular ground-glass nodule pattern in acute myeloid leukemia patients receiving cytosine arabinoside chemotherapy: an important form of drug-induced lung disease.

Centrilobular ground-glass nodule pattern in acute myeloid leukemia patients receiving cytosine arabinoside chemotherapy: an important form of drug-induced lung disease.

Comparison of low dose cytosine arabinoside, azacitidine and azacitidine venetoclax combination treatment as remission induction in elderly acute myeloid leukemia patients

Aims: Low-intensity therapies are widely preferred in the treatment of advanced age, fragile acute myeloid leukemia (AML) patients. In this study, we aimed to compare hematological recovery rates after first cycle chemotherapy and overall survival for advanced aged AML patients treated with azacitidine (AZA) or low dose cytosine arabinoside (LDCA) or venetoclax (Ven) with AZA combination.
 Methods: Ninety-one patients were retrospectively analyzed. 
 Results: Forty-one patients treated with LDCA, 30 patients treated with AZA and 20 patients treated with AZA+Ven were included in the study. Patients who received these three treatments and who achieved response and did not receive any other treatment during the follow-up period were included in the study. Median age at diagnosis was 70. The percentage of patients who achieved neutrophil recovery after the first cycle was 27%, 73% and 50% of the patients treated with LDCA, AZA and AZA+Ven respectively. The rate of patients who achieved platelet recovery was 60%, 80%, 70% respectively. Erythrocyte transfusion independency was 54% for LDCA patients, 73% for AZA patients and 60% for combination therapy. Overall survival was longer in patients receiving AZA+Ven than other treatment groups while grade 3-4 infections were more common in the first cycle of the treatment.
 Conclusion: According to our study, patients treated with AZA had better platelet and neutrophil recovery rates with also longer overall survival than patients treated with LDCA, but total overall survival was superior in AZA+Ven combination. Hypomethylating agents with venetoclax is a preferable treatment option in elderly AML patients.

Retrospective evaluation of prognosis and survival with various immunosuppressants in 82 dogs diagnosed with meningoencephalitis of unknown etiology (2010–2021)

BackgroundMeningoencephalomyelitis of unknown etiology (MUE) is a comprehensive term for non-infectious inflammatory brain diseases of the central nervous system (CNS) caused by abnormal autoimmune responses. This study aims to compare the differences in survival and clinical response of MUE according to the adjuvant immunosuppressant use. Medical records of 82 dogs diagnosed with MUE were reviewed retrospectively.ResultsThe overall survival time was 769 days (range 14–2687 days). The median survival time for each adjunctive was: leflunomide 1035 days (range 126–2163 days), mycophenolate mofetil 865 days (range 39–2191 days), cyclosporin 441 days (range 11–2176 days), cytosine arabinoside 754 days (range 6–1898 days) and a combination of mycophenolate mofetil and cytosine arabinoside 132 days (range 23–1227 days). There was no significant difference in the incidence rate of adverse events according to the immunosuppressants, but moderate to severe anemia was confirmed in 3 patients (18.7%) in the leflunomide group.ConclusionsThe survival time and response rate of MUE dogs differed depending on which adjunctive immunosuppressants were used. Leflunomide showed a long survival time and a relatively good response rate in dogs with MUE. However, a large-scale further study with standardized doses of immunosuppressants and supportive treatment and constant monitoring interval is needed.

Exosome-shuttled FTO from BM-MSCs contributes to cancer malignancy and chemoresistance in acute myeloid leukemia by inducing m6A-demethylation: A nano-based investigation

Although bone marrow mesenchymal stem cells (BM-MSCs)-derived exosomes have been reported to be closely associated with acute myeloid leukemia (AML) progression and chemo-resistance, but its detailed functions and molecular mechanisms have not been fully delineated. Besides, serum RNA m6A demethylase fat mass and obesity-associated protein (FTO)-containing exosomes are deemed as important indicators for cancer progression, and this study aimed to investigate the role of BM-MSCs-derived FTO-exosomes in regulating the malignant phenotypes of AML cells. Here, we verified that BM-MSCs-derived exosomes delivered FTO to promote cancer aggressiveness, stem cell properties and Cytosine arabinoside (Ara-C)-chemoresistance in AML cells, and the underlying mechanisms were also uncovered. Our data suggested that BM-MSCs-derived FTO-exo demethylated m6A modifications in the m6A-modified LncRNA GLCC1 to facilitate its combination with the RNA-binding protein Hu antigen R (HuR), which further increased the stability and expression levels of LncRNA GLCC1. In addition, LncRNA GLCC1 was verified as an oncogene to facilitate cell proliferation and enhanced Ara-C-chemoresistance in AML cells. Further experiments confirmed that demethylated LncRNA GLCC1 served as scaffold to facilitate the formation of the IGF2 mRNA binding protein 1 (IGF2BP1)-c-Myc complex, which led to the activation of the downstream tumor-promoting c-Myc-associated signal pathways. Moreover, our rescuing experiments validated that the promoting effects of BM-MSCs-derived FTO-exo on cancer aggressiveness and drug resistance in AML cells were abrogated by silencing LncRNA GLCC1 and c-Myc. Thus, the present firstly investigated the functions and underlying mechanisms by which BM-MSCs-derived FTO-exo enhanced cancer aggressiveness and chemo-resistance in AML by modulating the LncRNA GLCC1-IGF2BP1-c-Myc signal pathway, and our work provided novel biomarkers for the diagnosis, treatment and therapy of AML in clinic.

CHD4 Promotes Tumor Formation, Survival, and Resistance to Genotoxic Therapeutics in TP53 Mutant T-Cell Acute Lymphoblastic Leukemia Cells through the NuRD Chromatin Remodeling Complex

T-Cell acute leukemia(T-ALL) though generally responsive to current chemotherapy remains incurable in over 50% of adult patients. Importantly, the survival for patients with TP53 mutant T-ALL disease is less than 10%. We have previously shown the role of the Methyl Binding Domain protein 2-Nucleosome Remodeling and Deacetylase (MBD2-NURD) chromatin remodeling complex in triple negative breast cancer cell growth and the role of the NuRD component, Chromatin-helicase-binding protein 4(CHD4), in tumor colony formation and genotoxic resistance in acute myeloid leukemia. In the present study, we have examined the role of specific NuRD complexes and CHD4 in T-cell acute leukemia cells with mutant TP53. The prototypical NuRD complex possesses both a histone deacetylase (HDCC) sub-complex and an ATPase chromatin remodeling sub-complex containing CHD4 linked to MBD2 or MBD3 of the HDCC. CHD4 is linked to the MBD2/3 anchors of the NuRD complex, via GATAD2A or GATAD2B. Depletion of CHD4 was found to increase the rate of apoptosis in several TP53 mutant T-ALL cell lines including Jurkat, MOLT4, RPMI and CCRF by up to 5 to 10-fold. Likewise, depletion of both MBD2 and MBD3 also increased apoptosis and sensitization to the standard genotoxic chemotherapeutic agent, cytosine arabinoside (Ara-C) but had only minimal effects in normal human CD34+ hematopoietic progenitor cells. Depletion of GATAD2B and GATAD2A by shRNA also resulted in a significantly increased survival of 60 days compared to 20 days in Scramble shRNA controls, in a xenogeneic mouse model of T-ALL. Depletion of CHD4 resulted in a profound (10 to 100-fold) decrease in colony formation of the TP53 mutant T-ALL cell lines in methylcellulose. RNA seq analyses identified the apoptosis, ferroptosis and mitophagy pathways as potential mechanisms for the striking effect of NURD disruption on colony formation. In summary, CHD4, through the NuRD complex, promotes tumor cell formation, survival and therapeutic resistance of TP53 mutant T-ALL cells. Current efforts are aimed at validating these findings in primary T-ALL cells and structure-function studies to advance development of tool compounds for disrupting the NuRD complex, with the long-term goal of developing improved small molecule therapeutics for treatment resistant acute leukemia.

Acute Lymphocytic Leukemia (ALL) in Pregnancy, Case Report and Literature Review

Introduction: Leukemia is rare in pregnancy, occurring in up to 1 in 100,000 pregnancies. A 28F G2P1 was diagnosed at our institution with Philadelphia (Ph) negative B-ALL at 24 weeks' gestation. She was induced with UKALL14 and achieved a flow negative complete remission post-induction. During induction chemotherapy, regular ultrasound scans showed that the fetus was growing normally for gestational age. The patient was kept on weekly vincristine and prednisone and had an elective c-section at 31+3 weeks, in light of her previous caesarean section, poor bishop score, and in order for her to safely resume chemotherapy. Baby girl had an uneventful hospital course and was discharged after 29 days. Given the sparse data on this challenging topic, we decided to review the literature for all reported cases of ALL in pregnancy. Methods : We reviewed the literature for all reported cases of ALL from 2000 to 2023. We collected available data on the patient, pregnancy, and fetal outcome as well as leukemia characteristics and chemotherapy received. Results: We found 57 patients across 20 studies. The median age at diagnosis was 26 years (range 16-41 years). Most affected pregnancies were during the second trimester (T2) (n 23/57) and third trimester (T3) (n 20/57). The subtype of ALL was reported in 49 patients; of those, B ALL was the most common (n 35/49). Ph was reported positive in eight patients. A total of 53 patients received chemotherapy, of those 33 patients were received during pregnancy, while 13 were after pregnancy, and the remaining 7 had unclear timing. Patients received different combinations of standard ALL chemotherapy agents including vincristine (n 49/53), cyclophosphamide (n 25/53), prednisone (n 42/53), dexamethasone (n 23/53), L-asparaginase (n 20/53), pegaspargase (n 1/53), daunorubicin (n 36/53), doxorubicin (n 7/53), idarubicin (n 4/53), cytarabine (n 11/53), 6-mercaptopurine (n 8/53), cytosine arabinoside (n 1/53), and methotrexate was given to 8 patients intrathecally during pregnancy; 6 during T2 and 2 during the first trimester (T1). Dasatinib and imatinib were given to two patients at 33 and 24 weeks respectively. There were no reports of patients who were treated with immune therapy while pregnant. All four patients who did not receive any treatment died from progressive disease. Complete remission (CR) was reported in 45 patients. One patient died during induction from septicaemia, five were refractory to induction chemotherapy and 2 did not have induction outcome reported. Of those who achieved a CR, 21 were reported alive and 16 reported dead at last follow up. Among those mortalities, 8 were due to relapsed leukemia, 3 due to infectious causes, 2 due to respiratory failure and 2 from unspecified causes. Five patients were reported to have persistent or refractory leukemia, 4 of whom died. Among the 14 T1 pregnancies, 10 were terminated electively, 3 spontaneously, and there was one maternal death due to declining treatment. Three patients received chemotherapy during T1, two suffered a spontaneous abortion and one had a missed miscarriage. Among the 23 T2 pregnancies, 17 resulted in live deliveries, one stillbirth during chemotherapy, one maternal death and 4 spontaneous abortions; 2 of which received chemotherapy during pregnancy, one did not receive treatment and one abortion with unclear timing of chemotherapy initiation. Among the 20 T3 pregnancies, 19 had successful deliveries and one stillbirth at an unindicated gestational age after receiving chemotherapy. Five babies were reported to have low birth weight, four had neonatal cerebral ischemia, one had intraventricular hemorrhage and one suffered from intestinal obstruction 2 weeks after delivery. All babies were discharged from hospital with no adverse congenital or developmental complications. Conclusion : Treatment of women presenting with ALL at or beyond T2 is possible with high early remission rates for the mothers and delivery of healthy babies. The outcome is highly dependent on the gestational age. It is important that more cases are reported on this topic due to its challenging and multidisciplinary nature especially given the sparse data available and potential for reporting bias.

A randomised evaluation of low-dose cytosine arabinoside plus lenalidomide versus single-agent low-dose cytosine arabinoside in older patients with acute myeloid leukaemia: Results from the LI-1 trial.

Improving outcomes for older patients with acute myeloid leukaemia remains an unmet need. As part of the LI-1 trial, we evaluated lenalidomide (LEN) in combination with low-dose cytosine arabinoside (LDAC) in patients aged >60 years unfit for intensive therapy and compared this to LDAC alone. Two hundred and two patients, randomised 1:1, were evaluable. Overall response rate (CR + CRi) was higher for LDAC + LEN versus LDAC (26% and 13.7% respectively p = 0.031). However, there was no difference in overall survival between the arms (14% and 11.5% at 2 years for LDAC + LEN and LDAC respectively). The addition of LEN was associated with increased toxicity and supportive care requirements.

Maternal supplementation of alpha-lipoic acid ameliorates prenatal cytarabine-induced mutilation in reproductive development and function in F1 male adult rats.

Cytarabine (CYT), a prevalent anticancer drug for blood cancers, detrimentally affects male reproductive development and function. Alpha-lipoic acid (ALA), a universal antioxidant, offers defense against chemical-induced reproductive dysfunction. Our study sought to explore ALA's protective role against prenatal CYT-induced reproductive impairment in F1 male adult rats. Pregnant rats were divided into 5 groups and administered normal saline, ALA 200mg/kg, CYT 12.5mg/kg, CYT 25mg/kg, and CYT 25mg/kg + ALA 200mg/ kg from gestational day 8 to 21. On postnatal day 73, F1 male rats were sacrificed, and general, oxidative, steroidogenic, spermatogenic, histological, and morphometrical parameters were evaluated. Prenatal CYT caused dose-dependent reductions in body weight, testis, and accessory gland weights; elevated oxidative stress; delayed puberty onset; sperm anomalies (decreased count, motility, viability, seminal fructose; increased morphological anomalies); impeded steroidogenesis (lower testosterone, follicle-stimulating hormone, luteinizing hormone, 3β-Hydroxysteroid dehydrogenase(HSD), 17β-HSD, and elevated cholesterol); and testicular histopathological and morphometric disturbances. Maternal supplementation of ALA was found to alleviate all the CYT-induced reproductive disruptions. The present work accentuates the beneficial actions of ALA against CYT-induced impairment in reproductive development and functions by combating disruptions in oxidative balance, steroidogenesis, spermatogenesis, and testicular histological aberrations. However, future experimental and clinical studies are warranted to explore the molecular mechanisms involved in the ALA's protection against prenatal CYT-induced testicular injury.

Investigation of side effects to treatment and cause of death in 63 Scandinavian dogs suffering from meningoencephalitis of unknown origin: a retrospective study

BackgroundMeningoencephalitis of unknown origin is a common cause of severe neurological disease in dogs. The term covers a heterogeneous group of noninfectious inflammatory diseases, with immune dysregulation widely accepted as the underlying disease mechanism. Current treatment consists of immunosuppression, with corticosteroids being the mainstay of virtually all treatment regimens. However, side effects of corticosteroids can be severe, and might be the cause of death in some patients. This retrospective, multi-centric study aimed at describing a population of Scandinavian dogs with meningoencephalitis of unknown origin in regards to reported side effects and cause of death, and to highlight possible differences in survival, when comparing corticosteroid monotherapy with other treatment regimens.ResultsWithin the 5-year study period, 63 dogs were included. Of these, 35 (55.6%) died or were euthanized during the study period. Median survival time from time of diagnosis based on Kaplan-Meier curves for the overall population was 714 days (equivalent to around 25 months, range 0-1678 days). There was no statistically significant difference (P = 0.31) in survival between dogs treated with corticosteroid monotherapy (n = 26, median survival time 716 days, equivalent to around 25 months, range 5–911 days), dogs receiving a combination of corticosteroids and ciclosporin (n = 15, median survival time 916 days, equivalent to around 31 months, range 35–1678 days), and dogs receiving corticosteroids combined with either cytosine arabinoside, leflunomide, or a combination of 2 or more add-on drugs (n = 13, median survival time 1186 days, equivalent to around 40 months, range 121–1640 days). Side effects were registered for 47/63 dogs. Polyphagia (n = 37/47), polyuria/polydipsia (n = 37/47), diarrhea (n = 29/47) and lethargy (n = 28/47) were most frequently reported. The most common cause for euthanasia was relapse (n = 15/35, 42.9%), followed by insufficient or lack of treatment response (n = 9, 25.7%). Side effects were the direct cause of euthanasia in 2/35 dogs (5.7%).ConclusionsA large proportion of dogs in the overall population were euthanized due to relapse, emphasizing a need for treatment regimens aimed at specifically preventing relapse for an improved long-term survival. Side effects in dogs receiving corticosteroid monotherapy were rarely a direct cause of death, but were reported for all dogs. No statistically significant difference in survival was found when corticosteroid monotherapy was compared to other treatment regimens.

Aptamer-modified chitosan-capped mesoporous silica nanoparticles for co-delivery of cytarabine and daunorubicin in leukemia

In this study, surface modified mesoporous silica nanoparticles (MSNs) were prepared for the targeted delivery of the anticancer agents, daunorubicin (DNR) and cytarabine (CTR), against K562 leukemia cancer cell lines. The MSNs were surface-modified with pH-sensitive chitosan (CS) to prevent the burst release of anticancer agents at the physiological pH of 7.4 and to enable a higher drug release at lower pH and higher concentration of glutathione. Finally, the MSNs were surface modified with KK1B10 aptamer (Apt) to enhance their uptake by K562 cells through ligand-receptor interactions. The MSNs were characterized using different methods and both in vitro and in vivo experiments were utilized to demonstrate their suitability as targeted anticancer agents. The resultant MSNs exhibited an average particle size of 295 nm, a surface area of 39.06 m2/g, and a cumulative pore volume of 0.09 cm3/g. Surface modification of MSNs with chitosan (CS) resulted in a more regulated and acceptable continuous release rate of DNR. The drug release rate was significantly higher at pH 5 media enriched with glutathione, compared to pH 7.4. Furthermore, MSNs coated with CS and conjugated with aptamer (MSN-DNR + CTR@CS-Apt) exhibited a lower IC50 value of 2.34 µg/ml, compared to MSNs without aptamer conjugation, which displayed an IC50 value of 12.27 µg/ml. The results of the cell cycle analysis indicated that the administration of MSN-DNR + CTR@CS-Apt led to a significant increase in the population of apoptotic cells in the sub-G1 phase. Additionally, the treatment arrested the remaining cells in various other phases of the cell cycle. Furthermore, the interactions between Apt-receptors were found to enhance the uptake of MSNs by cancer cells. The results of in vivo studies demonstrated that the administration of MSN-DNR + CTR@CS-Apt led to a significant reduction in the expression levels of CD71 and CD235a markers, as compared to MSN-DNR + CTR@CS (p < 0.001). In conclusion, the surface modified MSNs prepared in this study showed lower IC50 against cancer cell lines and higher anticancer activity in animal models.

Oral cytarabine ocfosfate pharmacokinetics and assessment of leukocyte biomarkers in normal dogs.

Cytosine arabinoside (Ara-C) is a nucleoside analog prodrug utilized for immunomodulatory effects mediated by its active metabolite Ara-CTP. Optimal dosing protocols for immunomodulation in dogs have not been defined. Cytarabine ocfosfate (CO) is a lipophilic prodrug of Ara-C that can be administered PO and provides prolonged serum concentrations of Ara-C. Provide pharmacokinetic data for orally administered CO and determine accumulation and functional consequences of Ara-CTP within peripheral blood leukocytes. Three healthy female hound dogs and 1 healthy male Beagle. Prospective study. Dogs received 200 mg/m2 of CO PO q24h for 7 doses. Serum and cerebrospinal fluid (CSF) CO and Ara-C concentrations were measured by liquid chromatography-tandem mass spectroscopy (LC-MS/MS). Complete blood counts, flow cytometry, and leukocyte activation assays were done up to 21 days. Incorporation of Ara-CTP within leukocyte DNA was determined by LC-MS/MS. Maximum serum concentration (Cmax ) for Ara-C was 456.1-724.0 ng/mL (1.88-2.98 μM) and terminal half-life was 23.3 to 29.4 hours. Cerebrospinal fluid: serum Ara-C ratios ranged from 0.54 to 1.2. Peripheral blood lymphocyte concentrations remained within the reference range, but proliferation rates poststimulation were decreased at 6 days. Incorporation of Ara-CTP was not saturated and remained >25% of peak concentration at 13 days. Oral CO may produce prolonged serum Ara-C half-lives at concentrations sufficient to induce functional changes in peripheral leukocytes and is associated with prolonged retention of DNA-incorporated Ara-CTP. Application of functional and active metabolite assessment is feasible and may provide more relevant data to determine optimal dosing regimens for Ara-C-based treatments.

Effect of Granulocyte Colony-Stimulating Factor on the Development of Spermatogenesis in the Adulthood of Juvenile AML Mice Model Treated with Cytarabine.

Pediatric acute myeloid leukemia (AML) generally occurs de novo. The treatment of AML includes cytarabine (CYT) and other medications. The granulocyte-colony stimulating factor (GCSF) is used in the clinic in cases of neutropenia after chemotherapies. We show that the administration of GCSF in combination with CYT in AML-diagnosed mice (AML+CYT+GCSF) extended the survival of mice for additional 20 days. However, including GCSF in all treatment modalities does not affect the testis' weight or the histology of the seminiferous tubules (STs). We show that GCSF does not affect normal ST histology from AML-, CYT-, or (AML+CYT)-treated groups compared to the relevant treated group without GCSF 2, 4, and 5 weeks post-injection. However, when comparing the percentages of normal STs between the AML+CYT+GCSF-treated groups and those without GCSF, we observe an increase of 17%-42% in STs at 4 weeks and 5.5 weeks post-injection. Additionally, we show that the injection of GCSF into the normal, AML-alone, or CYT-alone groups, or in combination with AML, significantly decreases the percentage of STs with apoptotic cells compared to the relevant groups without GCSF and to the CT (untreated mice) only 2 weeks post-injection. We also show that injection of GCSF into the CT group increases the examined spermatogonial marker PLZF within 2 weeks post-injection. However, GCSF does not affect the count of meiotic cells (CREM) but decreases the post-meiotic cells (ACROSIN) within 4 weeks post-injection. Furthermore, GCSF not only extends the survival of the AML+CYT-treated group, but it also leads to the generation of sperm (1.2 ± 0.04 × 106/mL) at 5.5 weeks post-injection. In addition, we demonstrate that the injection of GCSF into the CT group increases the RNA expression level of IL-10 but not IL-6 compared to CT 2 weeks post-treatment. However, the injection of GCSF into the AML-treated group reverses the expression levels of both IL-10 and IL-6 to normal levels compared to CT 2 weeks post-injection. Thus, we suggest that the addition of GCSF to the regimen of AML after CYT may assist in the development of future therapeutic strategies to preserve male fertility in AML prepubertal patients.

Evaluation of leukapheresis and leukapheresis with additional cytoreduction in acute leukemia with hyperleukocytosis

Background Hyperleukocytosis is a high-mortality emergency that must be diagnosed and treated promptly. The treatment options are low-dose cytosine arabinoside, hydroxyurea, steroids and leukapheresis. The risks and benefits of leukapheresis and leukapheresis with cytoreductive drugs in hyperleukocytosis are unclear. Therefore, we aimed to evaluate the efficacy of leukapheresis and the effect of adding cytoreductive drugs to leukapheresis in reducing leukocyte count and mortality in our patients.&#x0D; Material and Methods Thirty-four adult patients with acute leukaemia who underwent leukapheresis were included in this retrospective study.&#x0D; Results The median age was 66.5 years old, and 88.2% of the patients were acute myeloid leukaemia. The total number of leukapheresis was 69 cycles, and the median number of the procedure was 2. The most common symptoms were associated with the pulmonary system (67.6%). The median follow-up was 17.5 days. The mean reduction of leukocyte count was 69,112/mm3, and the efficacy of leukapheresis was 40.9%. The decrease in leukocyte and platelet counts was statistically significant when compared before and after leukapheresis. The mortality rate was 76.5% during hospitalization. While 24 patients received concomitant cytoreductive drugs with leukapheresis, ten did not. There was no statistically significant difference between these groups regarding reducing leukocyte count, efficiency of leukapheresis and mortality (p values 0.857, 0.562 and 0.553).&#x0D; Conclusions In our study, we showed the efficacy of leukapheresis in hyperleukocytosis but failed to show any difference in leukocyte reduction or mortality with additional cytoreductive drugs. Leukapheresis with concomitant cytoreduction does not abolish or increase mortality.

Degradation of cytostatics methotrexate and cytarabine through physico-chemical and advanced oxidative processes: influence of pH and combined processes on the treatment efficiency

ABSTRACT Environmental release of wastewater that contains cytostatic drugs can cause genotoxic impact, since these drugs act directly on the genetic material of aquatic organisms. Thus, the aim of this study was to evaluate the removal of the cytostatic drugs cytarabine (CTR) and methotrexate (MTX) using different physico-chemical methods individually (i.e. US, O3, H2O2 and UV) and combined (i.e. O3/US, US/H2O2, O3/H2O2 and O3/US/H2O2) under different pH conditions (4, 7 and 10). In the degradation tests, the efficiency of the methods applied was found to be dependent on the pH of the solution, with the degradation of CTR being better at pH 4 and MTX at pH 7 and pH 10. The US, H2O2 and US + H2O2 methods were the least efficient in degrading CTR and MTX under the pH conditions tested. The highest MTX degradation rate after 16 min of treatment at pH 7 was achieved by the O3 + H2O2 method (97.05% – C/C0 = 0.0295). For CTR, the highest degradation rate after 16 min of treatment was achieved by the O3 process (99.70% – C/C0 = 0.0030) at pH 4. In conclusion, most of the treatment methods tested for the degradation of CTR and MTX are effective. Notably, ozonolysis is an efficient process applied alone. Also, in combination with other methods (US + O3, O3 + H2O2 and O3 + H2O2 + US) it increases the degradation performance, showing a rapid removal rate of 70–94% in less than 4 min of treatment.

AraC interacts with p75NTR transmembrane domain to induce cell death of mature neurons

Cytosine arabinoside (AraC) is one of the main therapeutic treatments for several types of cancer, including acute myeloid leukaemia. However, after a high-dose AraC chemotherapy regime, patients develop severe neurotoxicity and cell death in the central nervous system leading to cerebellar ataxia, dysarthria, nystagmus, somnolence and drowsiness. AraC induces apoptosis in dividing cells. However, the mechanism by which it leads to neurite degeneration and cell death in mature neurons remains unclear. We hypothesise that the upregulation of the death receptor p75NTR is responsible for AraC-mediated neurodegeneration and cell death in leukaemia patients undergoing AraC treatment. To determine the role of AraC-p75NTR signalling in the cell death of mature neurons, we used mature cerebellar granule neurons’ primary cultures from p75NTR knockout and p75NTRCys259 mice. Evaluation of neurite degeneration, cell death and p75NTR signalling was done by immunohistochemistry and immunoblotting. To assess the interaction between AraC and p75NTR, we performed cellular thermal shift and AraTM assays as well as Homo-FRET anisotropy imaging. We show that AraC induces neurite degeneration and programmed cell death of mature cerebellar granule neurons in a p75NTR-dependent manner. Mechanistically, Proline 252 and Cysteine 256 residues facilitate AraC interaction with the transmembrane domain of p75NTR resulting in uncoupling of p75NTR from the NFκB survival pathway. This, in turn, exacerbates the activation of the cell death/JNK pathway by recruitment of TRAF6 to p75NTR. Our findings identify p75NTR as a novel molecular target to develop treatments for counteract AraC-mediated cell death of mature neurons.

Targeted Therapies in Pediatric Acute Myeloid Leukemia - Evolving TherapeuticLandscape.

Acute myeloid leukemia (AML) accounts for 25% of all leukemia diagnosis and is characterized by distinct cytogenetic and molecular profile. Advances in the understanding of the causative driver mutations, risk-based therapy and better supportive care have led to an overall improvement in survival with frontline therapy. Despite these improvements, a significant number fail either because of primary refractory disease to the conventional 7+3 combination of anthracyclines and cytosine arabinoside (Cytarabine; Ara-C) or experience relapse post remission. Salvage therapy is complicated by the cardiotoxicity driven limitations on the reuse of anthracyclines and development of resistance to cytarabine. In this chapter authors will review the recent studies with targeted agents for refractory AML including targets for immunotherapeutic strategies.

The role of m6A demethylase FTO in chemotherapy resistance mediating acute myeloid leukemia relapse

Acute myeloid leukemia (AML) is the most common hematopoietic malignancies, and chemotherapy resistance is one of the main causes of relapse. Because of lower survival rate for patients with relapse, it is pivotal to identify etiological factors responsible for chemo-resistance. In this work, direct MeRIP-seq analysis of sequential samples at stage of complete remission (CR) and relapse identifies that dysregulated N6-methyladenosine (m6A) methylation is involved in this progression, and hypomethylated RNAs are related to cell differentiation. m6A demethylase FTO is overexpressed in relapse samples, which enhances the drug resistance of AML cells in vivo and in vitro. In addition, FTO knockdown cells exhibit stronger capacity of differentiation towards granules and myeloid lineages after cytosine arabinoside (Ara-C) treatment. Mechanistically, FOXO3 is identified as a downstream target of FTO, the hypomethylation of FOXO3 mRNA affects its RNA degradation and further reduces its own expression, which ultimately result in attenuated cell differentiation. Collectively, these results demonstrate that FTO-m6A-FOXO3 is the main regulatory axis to affect the chemotherapy resistance of AML cells and FTO is a potential therapeutic target of chemotherapy resistance in AML.

FLT4 as a marker for predicting prognostic risk of refractory acute myeloid leukemia.

Treating patients with refractory acute myeloid leukemia (AML) remains challenging. Currently there is no effective treatment for refractory AML. Increasing evidence has demonstrated that refractory/relapsed AML is associated with leukemic blasts which can confer resistance to anticancer drugs. We have previously reported that high expression of Fms-related tyrosine kinase 4 (FLT4) is associated with increased cancer activity in AML. However, the functional role of FLT4 in leukemic blasts remains unknown. Here, we explored the significance of FLT4 expression in leukemic blasts of refractory patients and mechanisms involved in the survival of AML blasts. Inhibition or absence of FLT4 in AML blasts suppressed homing to bone marrow of immunocompromised mice and blocked engraftment of AML blasts. Moreover, FLT4 inhibition by MAZ51, an antagonist, effectively reduced the number of leukemic cell-derived colony-forming units and increased apoptosis of blasts derived from refractory patients when it was co-treated with cytosine arabinoside under vascular endothelial growth factor C, its ligand. AML patients who expressed high cytosolic FLT4 were linked to an AML-refractory status by internalization mechanism. In conclusion, FLT4 has a biological function in leukemogenesis and refractoriness. This novel insight will be useful for targeted therapy and prognostic stratification of AML.