Vosaroxin is a novel topoisomerase-II inhibitor with efficacy in relapsed and refractory acute myeloid leukaemia

Evaluation of Quinoline-Related Carboxylic Acid Derivatives as Prospective Differentially Antiproliferative, Antioxidative, and Anti-Inflammatory Agents

The higher prevalence of cancer and the unmet need for antioxidant/anti-inflammatory chemotherapeutic compounds with little side effect are of utmost importance. In addition, the increased likelihood of failure in clinical trials along with increasing development costs may have diminished the range of choices among newer drugs for clinical use. This has dictated the necessity to seek out novel medications by repurposing as it needs less time, effort, and resources to explore new uses of a current or unsuccessful medication. In this study, we examined the biological activity of 10 potential quinoline derivatives. Given the half-maximal inhibitory concentration (IC50 value) in lipopolysaccharide (LPS) induced inflammation of RAW264.7 mouse macrophages, all commercial FQs and selected quinolines (quinoline-4-carboxlic and quinoline-3-carboxylic acids) exerted impressively appreciable anti-inflammation affinities versus classical NSAID indomethacin without related cytotoxicities in inflamed macrophages. Conversely, all 14 tested compounds lacked antioxidative DPPH radical scavenging capacities as compared to ascorbic acid. Gemifloxacin, considerably unlike markets FQs, indomethacin and quinoline derivatives, exerted exceptional and differential antiproliferation propensities in colorectum SW480, HCT116, and CACO2, pancreatic PANC1, prostate PC3, mammary T47D, lung A375, and melanoma A549 adherent monolayers using the sulforhodamine B colorimetric method versus antineoplastic cisplatin. All quinoline derivatives and gemifloxacin alike, but not levofloxacin, ciprofloxacin, or indomethacin, displayed substantially selective viability reduction affinities in prolonged tumor incubations of cervical HELA and mammary MCF7 cells. Specifically kynurenic acid (hydrate), quinoline-2-carboxylic acid, quinoline-4-carboxylic acid, quinoline-3-carboxylic acid, and 1,2-dihydro-2-oxo-4-quinoline carboxylic acids possessed the most remarkable growth inhibition capacities against mammary MCF7 cell line, while quinoline-2-carboxylic acid was the only quinoline derivative with significant cytotoxicity on cervical HELA cancer cells. It is highly speculated that chelation with divalent metals via co-planarity with close proximity of the COOH and the N atom could have the potential molecular mechanism for optimally promising repurposed pharmacologies. Conclusively, this study revealed the considerably profound repurposed duality of cytotoxicity and anti-inflammation pharmacologies of quinoline derivatives. Activity-guided structural modifications of the present nuclear scaffolds can be inherently linked to the betterment and enhancement of their repurposed pharmacologies.

Design, synthesis, and biological evaluation of novel ciprofloxacin derivatives as potential anticancer agents targeting topoisomerase II enzyme

A series of novel ciprofloxacin (CP) derivatives substituted at the N-4 position with biologically active moieties were designed and synthesised. 14 compounds were 1.02- to 8.66-fold more potent than doxorubicin against T-24 cancer cells. Ten compounds were 1.2- to 7.1-fold more potent than doxorubicin against PC-3 cancer cells. The most potent compounds 6, 7a, 7b, 8a, 9a, and 10c showed significant Topo II inhibitory activity (83-90% at 100 μM concentration). Compounds 6, 8a, and 10c were 1.01- to 2.32-fold more potent than doxorubicin. Compounds 6 and 8a induced apoptosis in T-24 (16.8- and 20.1-fold, respectively compared to control). This evidence was supported by an increase in the level of apoptotic caspase-3 (5.23- and 7.6-fold, sequentially). Both compounds arrested the cell cycle in the S phase in T-24 cancer cells while in PC-3 cancer cells the two compounds arrested the cell cycle in the G1 phase. Molecular docking simulations of compounds 6 and 8a into the Topo II active site rationalised their remarkable Topo II inhibitory activity.

Antiproliferative properties of 7,8-Ethylene Diamine Chelator-Lipophilic Fluoroquinolone Derivatives Against colorectal cancer Cell Lines

BACKGROUND

Cancer is one of the most overwhelming diseases nowadays. It is considered the second cause of death after cardiovascular diseases. Due to the diversity of its types, stages, and genetic origin, there is no available drug to treat all cancers. Serious side effects and resistance to existing drugs are other problems in this struggle against cancer. In such quest, fluoroquinolones (FQs) offer a future promise as antiproliferative compounds due to safety, low cost, and lack of resistance.

OBJECTIVES

Therefore, this work aims at developing lipophilic FQs and screening their antiproliferative activity against colorectal cancer.

METHODS

Nine prepared FQs were investigated for antiproliferative activity utilizing in vitro SRB method. In comparison to the antiproliferative agent cisplatin, the assessment of antiproliferative activities of these novel FQs in a panel of colorectal cancer cell (crc) lines (HT29, HCT116, SW620, CACO2, SW480) and normal periodontal ligament fibroblasts for safety examination was performed. Antibacterial activity (MIC) was conducted against Staphylococcus aureus and Escherichia coli standard strains using the broth double dilution method. Antioxidant properties were suspected as the mechanism of antiproliferative activity; thus, a DPPH test was performed to analyze the radical scavenging potency of FQs compared to ascorbic acid as a reference agent. FQs compounds 3-5(a-c) were prepared, characterized and their structure was confirmed using spectroscopy techniques.

RESULTS

All compounds manifested good to excellent antiproliferative activity on HT29, HCT116, and SW620 with high safety index. The reduced series 4a, 4b, and 4c exerted excellent micro to nanomolar antiproliferative activities on HT29, HCT116, and SW620, which were stronger than the reference cisplatin against all cells. The reduced group of compounds 4(a-c) revealed higher potency vs. both nitro and triazolo groups. On cell lines HT29, HCT116, and SW620 reduced 4a with 7,8-ethylene diamine substitution revealed the highest antiproliferative efficacy (IC50 value) approaching nanomolar affinity with higher safety vs. cisplatin. The most active compound, 4a, exhibited significant potency against HCT116 and SW620 with IC50 0.6 and 0.16 µM, respectively. Novel FQs (4a, 4b, and 4c) also showed strong radical scavenging activity with IC50 values (µM) 0.06, 23, and 7.99, respectively. Exquisitely 4a revealed a similar pattern of activity to doxorubicin, indicating a similar mechanism of action. Strong antiproliferative and weak antibacterial activities of series 4 endorse that their mechanism involves eukaryotic topoisomerase II inhibition. This work has revealed novel FQs with excellent anticancer activity against 5 colorectal cancer (HT29, HCT116, SW620, CACO2, SW480) cell lines with a potential chelation mechanism due to 7,8-ethylene diamine chelator bridge.

CONCLUSIONS

The new FQs have confirmed that more lipophilic compounds could be more active as hypothesized. The p-halogenated aniline, N1-Butyl group in addition to 3-COOH, 8-NH2 are all essential requirements for strong antiproliferative FQ of our FQ scaffold. This work emphasizes the role of C-8 amino as part of ethylene diamine group as an essential requirement for antiproliferative FQs for the first time in the literature, entailing its role toward potential antneoplastic FQs.

A Novel Class of Functionalized Synthetic Fluoroquinolones with Dual Antiproliferative - Antimicrobial Capacities

As vosaroxin as a fluoroquinolone (FQ) had anticancer effectiveness; this study aimed to screen new lipophilic FQs for their dual antimicrobial-antiproliferative activities. Using sulforhodamine B assay; 36 lipophilic FQs have been screened for antimicrobial propensities against S. aureus, E. coli, and C. albicans vs. the respective references ciprofloxacin and fluconazole. They were also explored against a battery of cancer cell lines. Normal periodontal ligament fibroblasts (PDL) were tested for safety examination in comparison to the cisplatin. Reduced FQ compound 4g (R-2, 4-DMeOACA) highly scored nanomolar potency with MIC value of 0.004 µM against gram-positive bacteria. The highest activity of the 36 lipophilic FQs was noted on Leukaemia K562, cervical HELA and pancreatic PANC-1 cancer cell lines with respective IC50 value of 0.005 µM for compound R-4-BuACA (4e), 0.40 µM with CHxCA (7a) and 0.11 µM for R-4-HxACA (4f). Tested FQs exhibited cytotoxicity in A549 lung cancer, MCF-7 and T47D breast cancer cell lines. The reduced 4e and 4f compounds have shown nanomolar inhibition against K562 (as of 4e), PANC-1 and MCF-7 (as of 4f) with IC50 values of 0.005, 0.11 and 0.30 µM, respectively. Succinctly FQs' dual gram-positive antibacterial-antineoplastic capacities expand on of drug design scaffolds in lead generation.<br />.

Screen of Unfocused Libraries Identified Compounds with Direct or Synergistic Antibacterial Activity

Antibiotic resistance is an increasingly important global public health issue, as major opportunistic pathogens are evolving toward multidrug- and pan-drug resistance phenotypes. New antibiotics are thus needed to maintain our ability to treat bacterial infections. According to the WHO, carbapenem-resistant Acinetobacter, Enterobactericaeae, and Pseudomonas are the most critical targets for the development of new antibacterial drugs. An automated phenotypic screen was implemented to screen 634 synthetic compounds obtained in-house for both their direct-acting and synergistic activity. Fourteen percent and 10% of the compounds showed growth inhibition against tested Gram-positive and Gram-negative bacteria, respectively. The most active direct-acting compounds showed a broad-spectrum antibacterial activity, including on some multidrug-resistant clinical isolates. In addition, 47 compounds were identified for their ability to potentiate the activity of other antibiotics. Compounds of three different scaffolds (2-quinolones, phenols, and pyrazoles) showed a strong potentiation of colistin, some being able to revert colistin resistance in Acinetobacter baumannii.

Immunobiological efficacy and immunotoxicity of novel synthetically prepared fluoroquinolone ethyl 6-fluoro-8-nitro-4-oxo-1,4-dihydroquinoline-3-carboxylate

The present study examined the cytotoxicity, anti-cancer reactivity, and immunomodulatory properties of new synthetically prepared fluoroquinolone derivative 6-fluoro-8-nitro-4-oxo-1,4-dihydroquinoline-3-carboxylate (6FN) in vitro. The cytotoxicity/toxicity studies (concentrations in the range 1-100μM) are focused on the cervical cancer cells HeLa, murine melanoma cancer cells B16, non-cancer fibroblast NIH-3T3 cells and reconstructed human epidermis tissues EpiDerm™. The significant growth inhibition of cancer cells HeLa and B16 was detected. The cytotoxicity was mediated via apoptosis-associated with activation of caspase-9 and -3. After 72h of treatment, the two highest 6FN concentrations (100 and 50μM) induced toxic effect on epidermis tissue EpiDerm™, even the structural changes in tissue were observed with concentration of 100μM. The effective induction of RAW 264.7 macrophages cell-release of pro- and anti-inflammatory T_H1, T_H2 and T_H17 cytokines, with anti-cancer and/or anti-infection activities, respectively, has been revealed even following low-dose exposition.

Treatment of Elderly Patients With Acute Myeloid Leukemia

OPINION STATEMENT

There is no standard of care for older patients with acute myeloid leukemia (AML) unfit for intensive chemotherapy. AML in older patients remains an area of significant unmet need necessitating novel therapeutic strategies. In older patients with normal cytogenetics, molecular variables can be helpful in refining risk. This molecular revolution has promoted a shift in the treatment paradigm of AML. Open new questions concern the necessity of an individualized therapy that may take into account not only an increase in survival but also the maintenance or improvement in terms of quality of life, the management of symptoms, and a maximization of time outside of hospital care. Molecular abnormalities provide the genomic footprint for the development of targeted therapies. Clinical trials testing the activity of these new agents are ongoing and may reshape treatment strategies for these patients. One promising strategy is to combine low-intensity treatments with novel agents.

Allogeneic stem cell transplantation in adult patients with acute myeloid leukaemia and 17p abnormalities in first complete remission: a study from the Acute Leukemia Working Party (ALWP) of the European Society for Blood and Marrow Transplantation (EBMT)

BACKGROUND

Acute myeloid leukaemia (AML) with 17p abnormalities (abn(17p)) carries a very poor prognosis due to high refractoriness to conventional chemotherapy, and allogeneic stem cell transplantation (allo-SCT) appears as the only potential curative option.

METHODS

To address outcomes after allo-SCT in patients with abn(17p), we retrospectively analysed de novo or secondary AML undergoing SCT between 2000 and 2013 from the EBMT registry.

RESULTS

One hundred thirty-nine patients with confirmed abn(17p) have been selected. At the time of transplant, one hundred twenty-five were in first remission (CR1). Median age was 54 years old. Abn(17p) was associated with a monosomal karyotype in 83% of patients, complex karyotype in 91%, monosomy 5 or 5q deletion (-5/5q-) in 55%, monosomy 7 (-7) in 39% and both -5/5q and -7 in 27%. Seventy-three patients (59%) had a reduced-intensity conditioning regimen. The 2-year overall survival (OS) and leukaemia-free survival (LFS) were 28 and 24%, respectively. The 2-year non-relapse mortality (NRM) was 15%, and 2-year relapse incidence (RI) was 61%. The cumulative incidence of grade II to IV acute graft-versus-host disease (GvHD) was 24% and that of chronic GvHD was 21%. In multivariate analysis, the presence of a -5/5q- in addition to abn(17p) was significantly and independently associated with worse OS, LFS and higher RI. Age and donor types did not correlate with outcome. Conditioning intensity was not statistically associated with OS, LFS and NRM when adjusted for patients' age.

CONCLUSIONS

In contrast to the dismal prognosis reported for AML patients harbouring abn(17p) undergoing conventional chemotherapy, allogeneic SCT provides responses in about 25% of those patients transplanted in CR1.

Is it possible to cure childhood acute myeloid leukaemia without significant cardiotoxicity?

Since cardiotoxicity is a life threatening late effect, a reduction of cardiotoxicity in the treatment of acute myeloid leukaemia (AML) is essential. This review is a compilation of the current knowledge about cardiotoxicity after AML treatment and of how future directions in treatment may affect its incidence. A total of six studies concerning AML and cardiotoxicity were identified. The incidence of late subclinical cardiotoxicity varied between 1·3 and 15·3%, and late clinical cardiotoxicity varied between 1·3 and 9·3%. Cumulative dose of anthracyclines (ACs) and history of relapse were the most common risk factors identified. No conclusions could be drawn about new, potentially less toxic ACs. Differences in treatment data and variations in study populations made comparisons uncertain. The echocardiographic techniques used in the majority of the studies are inferior to more modern echocardiographic methods. This decreases reproducibility and may increase the risk of overestimation of cardiotoxicity. In summary, AML cannot be cured today without ACs. However, some ACs may cause less cardiotoxicity than others. Furthermore there is currently no consensus on equipotent doses of ACs and risk factors for cardiotoxicity. Further research including randomized trials is needed to evaluate whether or not the potentially less cardiotoxic agents fulfil their promise.

The safety of treatment options for elderly people with acute myeloid leukemia

INTRODUCTION

Life expectancy in elderly patients with acute myeloid leukemia (AML) is a function of age, disability, and co-morbidity, combined with leukemia characteristics. There is currently no consensus regarding the optimal therapeutic strategy for older adults with AML. Although selected older adults with AML can benefit from intensive therapies, recent evidence supports the use of lower-intensity therapies in most patients and emphasizes the importance of tolerability and quality of life.

AREAS COVERED

Results of the current clinical trials and safety data are reviewed.

EXPERT OPINION

Treatment recommendations for elderly patients with AML need to be individualized. In order to avoid toxicities, hematologists should collaborate more with geriatricians to identify clues of vulnerability in elderly patients through the study of functional physical, physiological, cognitive, social, and psychological parameters.