Novel Approach for Bone Marrow Transplantation Conditioning in Acute Myelogenous Leukemia not Responding to the Induction Therapy Using Etoposide Carried in Lipid Core Nanoparticles: A Pilot Clinical Study

Allogeneic hematopoietic cell transplantation (HCT) is the treatment of choice for acute myelogenous leukemia (AML) not responding to induction therapy. It is a therapeutic choice for the blast phase of chronic myelogenous leukemia (CML-BP) in patients failing to respond to tyrosine kinase inhibitors (TKIs). Lipid core nanoparticles (LDEs) concentrate severalfold more in blast cells than in corresponding normal cells. Incorporation of anticancer drugs to LDE formulations increases the pharmacologic action and decreases the toxicity. We tested a drug-targeting system, LDE-etoposide plus total body irradiation (TBI; 1200 cGy dose), in 13 patients with AML not responding to the induction therapy and in 2 patients with CML-BP refractory to second-generation TKIs. The mean patient age was 46.7 years (range, 22 to 66 years). The LDE-etoposide dose was escalated at 20, 30, 40, 50, and 60 mg/kg. No patients developed grade 4 or 5 toxicity; however, mucositis grade 3 occurred in 6 patients, 3 patients experienced diarrhea, and 1 patient had an elevated total bilirubin level. No deaths were related to conditioning. All patients were successfully engrafted. The median times to neutrophil and platelet engraftment were 20 ± 5 days and 16 ± 4 days, respectively. Five patients (33.4%) had acute graft-versus-host-disease (GVHD), including 4 grade I, and 1 with grade II, and 8 patients (57.1%) had moderate-to-severe chronic GVHD. This pilot study shows the potential of LDE-etoposide plus TBI as an HCT conditioning regimen in AML patients not responding to the induction and refractory therapies for CML-BP patient. These findings pave the way for subsequent larger clinical trials.

Long-term fate of etoposide-induced micronuclei and micronucleated cells in Hela-H2B-GFP cells

Micronuclei are small nuclear cellular structures containing whole chromosomes or chromosomal fragments. While there is a lot of information available about the origin and formation of micronuclei, less is known about the fate of micronuclei and micronucleated cells. Possible fates include extrusion, degradation, reincorporation and persistence. Live cell imaging was performed to quantitatively analyse the fates of micronuclei and micronucleated cells occurring in vitro. Imaging was conducted for up to 96 h in HeLa-H2B-GFP cells treated with 0.5, 1 and 2 µg/ml etoposide. While a minority of micronuclei was reincorporated into the main nucleus during mitosis, the majority of micronuclei persisted without any alterations. Degradation and extrusion were observed rarely or never. The presence of micronuclei affected the proliferation of the daughter cells and also had an influence on cell death rates. Mitotic errors were found to be clearly increased in micronucleus-containing cells. The results show that micronuclei and micronucleated cells can, although delayed in cell cycle, sustain for multiple divisions.

Efficacy and Safety of Apatinib Combined with Etoposide in Patients with Recurrent Platinum-resistant Epithelial Ovarian Cancer: A Retrospective Study

Purpose: Advanced epithelial ovarian cancer (EOC) eventually develops into a recurrent platinum-resistant disease. The response to standard treatment and prognosis in patients with EOC is generally unsatisfactory. This study aimed to assess the efficacy and safety of apatinib combined with etoposide in patients with recurrent platinum-resistant EOC.

Materials and Methods: This is a single-center, retrospective, observational study. We have reviewed a total of 33 patients with recurrent platinum-resistant EOC from July 2017 to July 2018, who were regularly treated with apatinib and etoposide until disease progression or unacceptable toxic effects occurred.

Results: At the date of the review finished, 15 of 33 (45.5%) patients remained on the combined treatment of apatinib and etoposide, while the other 18 (54.5%) had discontinued. Although no complete response (CR) occurred, the overall response rate (ORR) and disease control rate (DCR) were 36.4% and 78.8% respectively. The median progression-free survival (PFS) was 5.6 months (95% CI, 4.1~7.1), and the median overall survival (OS) was 10.3 months (95% CI, 9.4~11.2). The most common adverse event was mucositis oral (60.6%), which caused the treatment discontinued in 4 (12.1%) patients. Other relatively common adverse events were hand-foot syndrome (42.4%), hypertension (39.4%), nausea or vomiting (30.3%), neutropenia (24.2%), fatigue (24.2%) and thrombocytopenia (21.2%). Grade 1 and 2 adverse events accounted for 63.6% (21/33).

Conclusion: The efficacy of apatinib combined with etoposide is encouraging in patients with platinum-resistant EOC. Most adverse events of this combined therapy were mild and tolerable. Severe mucositis oral was not rare, which needs more precautions.

Etoposide-mediated interleukin-8 secretion from bone marrow stromal cells induces hematopoietic stem cell mobilization

Background

We assessed the mechanism of hematopoietic stem cell (HSC) mobilization using etoposide with granulocyte-colony stimulating factor (G-CSF), and determined how this mechanism differs from that induced by cyclophosphamide with G-CSF or G-CSF alone.

Methods

We compared the clinical features of 173 non-Hodgkin’s lymphoma patients who underwent autologous peripheral blood stem cell transplantation (auto-PBSCT). Additionally, we performed in vitro experiments to assess the changes in human bone marrow stromal cells (hBMSCs), which support the HSCs in the bone marrow (BM) niche, following cyclophosphamide or etoposide exposure. We also performed animal studies under standardized conditions to ensure the following: exclude confounding factors, mimic the conditions in clinical practice, and identify the changes in the BM niche caused by etoposide-induced chemo-mobilization or other mobilization methods.

Results

Retrospective analysis of the clinical data revealed that the etoposide with G-CSF mobilization group showed the highest yield of CD34+ cells and the lowest change in white blood cell counts during mobilization. In in vitro experiments, etoposide triggered interleukin (IL)-8 secretion from the BMSCs and caused long-term BMSC toxicity. To investigate the manner in which the hBMSC-released IL-8 affects hHSCs in the BM niche, we cultured hHSCs with or without IL-8, and found that the number of total, CD34+, and CD34+/CD45- cells in IL-8-treated cells was significantly higher than the respective number in hHSCs cultured without IL-8 (p = 0.014, 0.020, and 0.039, respectively). Additionally, the relative expression of CXCR2 (an IL-8 receptor), and mTOR and c-MYC (components of IL-8-related signaling pathways) increased 1 h after IL-8 treatment. In animal studies, the etoposide with G-CSF mobilization group presented higher IL-8-related cytokine and MMP9 expression and lower SDF-1 expression in the BM, compared to the groups not treated with etoposide.

Conclusion

Collectively, the unique mechanism of etoposide with G-CSF-induced mobilization is associated with IL-8 secretion from the BMSCs, which is responsible for the enhanced proliferation and mobilization of HSCs in the bone marrow; this was not observed with mobilization using cyclophosphamide with G-CSF or G-CSF alone. However, the long-term toxicity of etoposide toward BMSCs emphasizes the need for the development of more efficient and safe chemo-mobilization strategies.

Comet assay on one- and two-cell mouse embryos

DNA damage quantified as the comet tail length was assessed using in vitro and in vivo comet assay on one- and two-cell mouse embryos obtained by natural mating. The use of a protocol with three layers of agarose reduces the embryo loss and makes it possible to study a small number of embryos. A significantly lower level of basal, but not induced DNA damage was found in embryos with cleaved zona pellucida compared to embryos with intact zona pellucida. There were no significant differences in the length of the comet's tail between embryos lysed in different lysis solutions, both in cases of basal and induced DNA damage. A significant increase in the comet tail length was detected in one-cell embryos of mice treated with methyl methanesulfonate and etoposide compared to the control. The data show that DNA damage induced in maternal germ cells persists, which can be detected in embryos using the comet assay.

Preparation and Biopharmaceutical Evaluation of Novel Polymeric Nanoparticles Containing Etoposide for Targeting Cancer Cells

Objectives

Polymeric nanoparticles are a promising novel drug delivery system and have advantages in cancer therapy. Etoposide is an anticancer agent that is used in the treatment of a variety of malignancies. The aim of the present study was to prepare and evaluate novel polymeric nanoparticles containing etoposide.

Materials and Methods

A 3² full factorial design was used to study the effect of Eudragit EPO and Pluronic F-68 on the characterization of nanoparticle suspensions. The polymeric nanoparticles were prepared by nanoprecipitation technique. The prepared nanoparticles was evaluated by percentage yield, drug polymer compatibility using fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetric (DSC) analysis, drug content, entrapment efficiency, zeta potential, particle size, scanning electron microscopy, X-ray diffraction, in vitro drug release studies, kinetic modeling, stability studies, and in vivo animal studies. Response surface plots were studied, which were generated using PCP dissolution software.

Results

Scanning electron microscopic studies confirmed their porous structure with a number of nanochannels. The FTIR spectra showed the stable character of etoposide in a mixture of polymers and revealed the absence of drug-polymer interactions. The DSC study revealed that the drug was involved in complexation with nanoparticles. The average particle size of etoposide nanoparticles was in the range of 114.4 nm to 136.7 nm. The zeta potential values were attained to ensure good stability of nanosuspensions. In vitro release of the drug from nanoparticles follows the Peppas model and showed controlled release behavior for a period of 24 h. The optimized nanoparticles were subjected to stability studies at 4°C in a refrigerator and the most suitable temperature for storage of etoposide nanoparticles found. The average targeting efficiency of drug-loaded nanoparticles was 41.88±0.030% of the injected dose in the liver, 25.66±0.320% in the spleen 13.82±0.090% in the lungs, 4.52±0.300% in the kidney, and 4.18±0.490% in the brain.

Conclusion

Etoposide loaded nanoparticles was found to be effective in sustained release.

Damage-associated molecular patterns (DAMPs) related to immunogenic cell death are differentially triggered by clinically relevant chemotherapeutics in lung adenocarcinoma cells

Background

Chemotherapeutics can stimulate immune antitumor response by inducing immunogenic cell death (ICD), which is activated by Damage-Associated Molecular Patterns (DAMPs) like the exposure of calreticulin (CRT) on the cell surface, the release of ATP and the secretion of High Mobility Group Box 1 (HMGB1).

Methods

Here, we investigated the levels of ICD-associated DAMPs induced by chemotherapeutics commonly used in the clinical practice of non-small cell lung cancer (NSCLC) and the association of these DAMPs with apoptosis and autophagy. A549 human lung adenocarcinoma cells were treated with clinically relevant doses of cisplatin, carboplatin, etoposide, paclitaxel and gemcitabine. We assessed ICD-associated DAMPs, cell viability, apoptosis and autophagy in an integrated way.

Results

Cisplatin and its combination with etoposide induced the highest levels of apoptosis, while etoposide was the less pro-apoptotic treatment. Cisplatin also induced the highest levels of ICD-associated DAMPs, which was not incremented by co-treatments. Etoposide induced the lower levels of ICD and the highest levels of autophagy, suggesting that the cytoprotective role of autophagy is dominant in relation to its pro-ICD role. High levels of CRT were associated with better prognosis in TCGA databank. In an integrative analysis we found a strong positive correlation between DAMPs and apoptosis, and a negative correlation between cell number and ICD-associated DAMPs as well as between autophagy and apoptosis markers. We also purpose a mathematical integration of ICD-associated DAMPs in an index (IndImunnog) that may represent with greater biological relevance this process. Cisplatin-treated cells showed the highest IndImmunog, while etoposide was the less immunogenic and the more pro-autophagic treatment.

Conclusions

Cisplatin alone induced the highest levels of ICD-associated DAMPs, so that its combination with immunotherapy may be a promising therapeutic strategy in NSCLC.

Quantitative phosphoproteomics to unravel the cellular response to chemical stressors with different modes of action

Damage to cellular macromolecules and organelles by chemical exposure evokes activation of various stress response pathways. To what extent different chemical stressors activate common and stressor-specific pathways is largely unknown. Here, we used quantitative phosphoproteomics to compare the signaling events induced by four stressors with different modes of action: the DNA damaging agent: cisplatin (CDDP), the topoisomerase II inhibitor: etoposide (ETO), the pro-oxidant: diethyl maleate (DEM) and the immunosuppressant: cyclosporine A (CsA) administered at an equitoxic dose to mouse embryonic stem cells. We observed major differences between the stressors in the number and identity of responsive phosphosites and the amplitude of phosphorylation. Kinase motif and pathway analyses indicated that the DNA damage response (DDR) activation by CDDP occurs predominantly through the replication-stress-related Atr kinase, whereas ETO triggers the DDR through Atr as well as the DNA double-strand-break-associated Atm kinase. CsA shares with ETO activation of CK2 kinase. Congruent with their known modes of action, CsA-mediated signaling is related to down-regulation of pathways that control hematopoietic differentiation and immunity, whereas oxidative stress is the most prominent initiator of DEM-modulated stress signaling. This study shows that even at equitoxic doses, different stressors induce distinctive and complex phosphorylation signaling cascades.

The "adductome": A limited repertoire of adducted proteins in human cells

Proteins form adducts with nucleic acids in a variety of contexts, and these adducts may be cytotoxic if not repaired. Here we apply a proteomic approach to identification of proteins adducted to DNA or RNA in normally proliferating cells. This approach combines RADAR fractionation of proteins covalently bound to nucleic acids with quantitative mass spectrometry (MS). We demonstrate that "RADAR-MS" can quantify induction of TOP1- or TOP2-DNA adducts in cells treated with topotecan or etoposide, respectively, and also identify intermediates in physiological adduct repair. We validate RADAR-MS for discovery of previously unknown adducts by determining the repertoires of adducted proteins in two different normally proliferating human cell lines, CCRF-CEM T cells and GM639 fibroblasts. These repertoires are significantly similar with one another and exhibit robust correlations in their quantitative profiles (Spearman r = 0.52). A very similar repertoire is identified by the classical approach of CsCl buoyant density gradient centrifugation. We find that in normally proliferating human cells, the repertoire of adducted proteins - the "adductome" - is comprised of a limited number of proteins belonging to specific functional groups, and that it is greatly enriched for histones, HMG proteins and proteins involved in RNA splicing. Treatment with low concentrations of formaldehyde caused little change in the composition of the repertoire of adducted proteins, suggesting that reactive aldehydes generated by ongoing metabolic processes may contribute to protein adduction in normally proliferating cells. The identification of an endogenous adductome highlights the importance of adduct repair in maintaining genomic structure and the potential for deficiencies in adduct repair to contribute to cancer.

Use of antioxidant could ameliorate the negative impact of etoposide on human sperm DNA during chemotherapy

RESEARCH QUESTION

A previous study showed that N-acetylcysteine (NAC), used after in-vitro exposure to the gonadotoxic chemotherapeutic drug etoposide, has the ability to decrease DNA damage in human spermatozoa; however, it showed no benefit when used before exposure. This study aimed to evaluate the impact of the NAC on the preservation of sperm quality during in-vitro exposure to etoposide.

DESIGN

Twenty semen samples were submitted to four experimental conditions: control, NAC-only incubation, etoposide-only incubation, and concomitant etoposide and NAC incubation. After in-vitro incubation, semen parameters, sperm chromatin condensation, sperm DNA fragmentation, sperm oxidative stress and sperm metabolism were used to evaluate the role of NAC in protecting human spermatozoa from etoposide.

RESULTS

Etoposide did not affect semen parameters, nor did it cause sperm oxidative damage or alterations in glycolytic profile. However, it induced chromatin decondensation and DNA fragmentation, which were fully prevented by NAC.

CONCLUSIONS

NAC was able to protect sperm DNA integrity during etoposide treatment in vitro, suggesting that NAC may be useful as an adjuvant agent in preserving male fertility during chemotherapy treatments.

Primitive neuroectodermal tumor of the uterus: Excellent clinical response following a multimodal treatment approach

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PNET of the genital tract is rare and often presents at an advanced stage highlighting their aggressive nature.

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Universally accepted treatment guidelines for PNETs are not available.

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A multimodal treatment approach may be effective in treating this rare disease.

We present a case report of a patient with uterine primitive neuroectodermal tumor (PNET). The patient underwent surgical management followed by pelvic radiation and intravaginal brachytherapy. Following a stable interval, the patient was found to have new onset spinal, pulmonary, and adrenal metastatic disease. She was subsequently started on high dose carboplatin and etoposide. An interval reduction of her metastatic disease was observed after three cycles. We conclude that a multimodal approach, including platinum-based adjuvant chemotherapy with etoposide, can be effective in patients who present with residual or recurrent disease after surgical and radiation therapy. However, more robust studies with longer follow-up periods will be needed to establish a consensus regarding effective treatment options.

DNA biodots based targeted theranostic nanomedicine for the imaging and treatment of non-small cell lung cancer

The light absorption and emission characteristics of DNA biodots (DNA-BD), along with biocompatibility, give them a high potential for use in various medical applications, particularly in diagnostic purpose. DNA, under high pressure and temperature, condenses to form luminescent biodots. The objective of this research is to develop DNA-biodots (BD) loaded and cetuximab conjugated targeted theranostic liposomes of etoposide for lung cancer imaging and therapy. Theranostic liposomes were prepared by using the solvent injection method and characterized for their particle size, polydispersity, zeta potential, encapsulation efficiency, and pH-dependent in-vitro release, SEM, TEM AFM, EDX, and XRD. The t₅₀% (time at which 50% of the drug releases from the preparation) of the formulations was pH-dependent, with a significant increase in the release at lower pH (5.5). To kill A549 adenocarcinoma cells, the etoposide (control) required significantly (p < 0.05) higher drug concentrations in comparison to non-targeted and; the non-targeted formulation required more concentrations in comparison to targeted liposomes. The in-vivo results demonstrated that CTX-TPGS decorated theranostic liposomes could be a promising carrier for lung theranostics due to their nano-size and selectivity towards EGFR overexpressed cells which provided an improved NSCLC targeted delivery of ETP in comparison to the non-targeted and control formulations.

Etoposide-mediated depletion of peripheral blood monocytes post s.aureus infection attenuates septic arthritis by modulating macrophage-derived factors responsible for inflammatory destruction

S.aureus induced septic arthritis remains a serious medical concern due to its rapidly progressive disease profile. The multidrug resistant nature of S.aureus demands the development of new strategies for the treatment of S.aureus arthritis. Since monocyte/macrophage population has been recognized as an important axis in joint inflammation and destruction, selective depletion of peripheral blood monocytes might influence the outcome and progression of the disease. Therefore, in this study we have put forward the concept of monocyte depletion by using etoposide, a drug that selectively depletes the monocyte/macrophage population. Mice were inoculated with live S.aureus for the development of septic arthritis. Post S.aureus infection, etoposide was subcutaneously injected. The severity of arthritis was found to be significantly low in the etoposide treated mice throughout the course. Arthritis index, histopathological analysis and TRAP staining images confirmed effectiveness of etoposide treatment in regulating inflammation and bone cartilage destruction. Lower levels of inflammatory cytokines, ROS, MMP-2, RANKL, OPN and plasmin reflected less severe arthritic destruction after etoposide treatment in arthritic mice. The bacterial load was not increased after etoposide treatment. Together, the presented data suggested that monocyte depletion by etoposide might represent an alternative therapeutic strategy for the treatment of S.aureus arthritis.

Physical and chemical stability of a generic etoposide formulation as an alternative to etoposide phosphate

The generic Mylan® etoposide (ETP) has been investigated as an alternative for Etopophos®, in part due to a global shortage of the latter. The generic alternative is different both in its formulation and in its very limited stability (6 h at 25 °C against 4 days for Etopophos®) once reconstituted in ready-to-use chloride or glucose solutions. Its intrinsic stability has been thoroughly studied under various conditions. Two degradation products resulting from hydrolysis were characterized by LC-HR-MSⁿ and supported by density functional theory calculations of the frontier molecular orbitals energies, molecular electrostatic potential mapping, and Mulliken charge analysis. Chemical degradation increases with temperature and can be fitted to a zero order kinetic model with a half-life of 119 days and a kinetic constant of 0.0028 mM day^-1. Precipitation was only observed in solutions at 5 °C and -20 °C indicating that at these temperatures the reconstituted solutions are thermodynamically metastable. In conclusion, ETP at concentrations of 0.68 and 1 mM prepared and stored at 25 °C under good manufacturing practices remained unchanged over a period of 21 days irrespective of the nature of the solvents or the type of container.

Bioflavonoids cause DNA double-strand breaks and chromosomal translocations through topoisomerase II-dependent and -independent mechanisms

Bioflavonoids have a similar chemical structure to etoposide, the well-characterized topoisomerase II (Top2) poison, and evidence shows that they also induce DNA double-strand breaks (DSBs) and promote genome rearrangements. The purpose of this study was to determine the kinetics of bioflavonoid-induced DSB appearance and repair, and their dependence on Top2. Cells were exposed to bioflavonoids individually or in combination in the presence or absence of the Top2 catalytic inhibitor dexrazoxane. The kinetics of appearance and repair of γH2AX foci were measured. In addition, the frequency of resultant MLL-AF9 breakpoint cluster region translocations was determined. Bioflavonoids readily induced the appearance of γH2AX foci, but bioflavonoid combinations did not act additively or synergistically to promote DSBs. Myricetin-induced DSBs were mostly reduced by dexrazoxane, while genistein and quercetin-induced DSBs were only partially, but significantly, reduced. By contrast, luteolin and kaempferol-induced DSBs increased with dexrazoxane pre-treatment. Sensitivity to Top2 inhibition correlated with a significant reduction of bioflavonoid-induced MLL-AF9 translocations. These data demonstrate that myricetin, genistein, and quercetin act most similar to etoposide although with varying Top2-dependence. By contrast, luteolin and kaempferol have distinct kinetics that are mostly Top2-independent. These findings have implications for understanding the mechanisms of bioflavonoid activity and the potential of individual bioflavonoids to promote chromosomal translocations. Further, they provide direct evidence that specific Top2 inhibitors or targeted drugs could be developed that possess less leukemic potential or suppress chromosomal translocations associated with therapy-related and infant leukemias.

Adrenocortical carcinoma masquerading as pheochromocytoma: a histopathologic dilemma

SUMMARY

Adrenocortical carcinoma (ACC) is an aggressive cancer that originates in the cortex of the adrenal gland and generally has a poor prognosis. ACC is rare but can be more commonly seen in those with cancer predisposition syndromes (e.g. Li-Fraumeni and Lynch Syndrome). The diagnosis of ACC is sometimes uncertain and it requires the use of precise molecular pathology; the differential diagnosis includes pheochromocytoma, adrenal adenoma, renal carcinoma, or hepatocellular carcinoma. We describe a case of a 57-year-old woman with Lynch Syndrome and metastatic ACC who was initially diagnosed as having pheochromocytoma. The tumor was first identified at 51 years of age by ultrasound followed by a CT scan. She underwent a left adrenalectomy, and the histopathology identified pheochromocytoma. Two years later, she had tumor recurrence with imaging studies showing multiple lung nodules. Following a wedge resection by video-assisted thoracoscopic surgery (VATS), histopathology was read as metastatic pheochromocytoma at one institution and metastatic ACC at another institution. She later presented to the National Institutes of Health (NIH) where the diagnosis of ACC was confirmed. Following her ACC diagnosis, she was treated with mitotane and pembrolizumab which were stopped due to side effects and progression of disease. She is currently receiving etoposide, doxorubicin, and cisplatin (EDP). This case highlights the importance of using a multi-disciplinary approach in patient care. Thorough evaluation of the tumor's pathology and analysis of the patient's genetic profile are necessary to obtain the correct diagnosis for the patient and can significantly influence the course of treatment.

LEARNING POINTS

Making the diagnosis of ACC can be difficult as the differential diagnosis includes pheochromocytoma, adrenal adenoma, renal carcinoma, or hepatocellular carcinoma. Patients with Lynch Syndrome should undergo surveillance for ACC as there is evidence of an association between Lynch Syndrome and ACC. Conducting a complete tumor immunoprofile and obtaining a second opinion is very important in cases of suspected ACC in order to confirm the proper diagnosis. A multi-disciplinary approach including genetic testing and a thorough evaluation of the tumor's pathology is imperative to ensuring that the patient receives an accurate diagnosis and the appropriate treatment.

A phase II study of etoposide, methylprednisolone, high-dose cytarabine, and oxaliplatin (ESHAOx) for patients with refractory or relapsed Hodgkin's lymphoma

We assessed the efficacy and toxicity of etoposide, methylprednisolone, high-dose cytarabine, and oxaliplatin (ESHAOx) combination chemotherapy in patients with refractory or relapsed Hodgkin's lymphoma (HL). This was an open-label, non-randomized, multi-center phase II study. The ESHAOx regimen consisted of intravenous (i.v.) etoposide 40 mg/m² on days 1 to 4, i.v. methylprednisolone 500 mg on days 1 to 5, i.v. cytarabine 2 g/m² on day 5, and i.v. oxaliplatin 130 mg/m² on day 1. Cycles (up to six) were repeated every 3 weeks. In an effort to identify prognostic markers, the serum levels of cytokines including tumor necrosis factor-α (TNF-α), C-reactive protein (CRP), and vascular endothelial growth factor (VEGF) were measured at the time of study entry. A total of 37 patients were enrolled, and 36 were available for evaluation of tumor response. The overall response rate was 72.2% (26/36) (complete response, 33.3% [12/36]; partial response, 38.9% [14/36]). The median time to progression was 34.9 months (95% confidence interval, 23.1-46.7 months). The most common grade 3 or 4 hematological adverse events were neutropenia (16/37, 43.2%), followed by thrombocytopenia (10/37, 27.0%). Grade 3 or 4 non-hematological adverse events were nausea (3/37, 8.1%), anorexia (2/37, 5.4%), mucositis (1/37, 2.7%), and skin rash (1/37, 2.7%). There were no treatment-related deaths. High levels of TNF-α and CRP were significantly associated with poorer overall survival (p = 0.00005 for TNF-α, p = 0.0004 for CRP, respectively). The ESHAOx regimen exhibited antitumor activity and an acceptable safety profile in patients with refractory or relapsed HL. Trial Registration: ClinicalTrials.gov. Registered February 21, 2011, https://clinicaltrials.gov/ct2/show/NCT01300156.

Targeting Tyrosyl-DNA phosphodiesterase I to enhance toxicity of phosphodiester linked DNA-adducts

Our genomic DNA is under constant assault from endogenous and exogenous sources, which needs to be resolved to maintain cellular homeostasis. The eukaryotic DNA repair enzyme Tyrosyl-DNA phosphodiesterase I (Tdp1) catalyzes the hydrolysis of phosphodiester bonds that covalently link adducts to DNA-ends. Tdp1 utilizes two catalytic histidines to resolve a growing list of DNA-adducts. These DNA-adducts can be divided into two groups: small adducts, including oxidized nucleotides, RNA, and non-canonical nucleoside analogs, and large adducts, such as (drug-stabilized) topoisomerase- DNA covalent complexes or failed Schiff base reactions as occur between PARP1 and DNA. Many Tdp1 substrates are generated by chemotherapeutics linking Tdp1 to cancer drug resistance, making a compelling argument to develop small molecules that target Tdp1 as potential novel therapeutic agents. Tdp1's unique catalytic cycle, which is centered on the formation of Tdp1-DNA covalent reaction intermediate, allows for two principally different targeting strategies: (1) catalytic inhibition of Tdp1 catalysis to prevent Tdp1-mediated repair of DNA-adducts that enhances the effectivity of chemotherapeutics; and (2) poisoning of Tdp1 by stabilization of the Tdp1- DNA covalent reaction intermediate, which would increase the half-life of a potentially toxic DNA-adduct by preventing its resolution, analogous to topoisomerase targeted poisons such as topotecan or etoposide. The catalytic Tdp1 mutant that forms the molecular basis of the autosomal recessive neurodegenerative disease spinocerebellar ataxia with axonal neuropathy best illustrates this concept; however, no small molecules have been reported for this strategy. Herein, we concisely discuss the development of Tdp1 catalytic inhibitors and their results.

Clinicopathologic analysis of primary gastroenteropancreatic poorly differentiated neuroendocrine carcinoma; A ten year retrospective study of 68 cases at Moffit Cancer Center

Objective:

To assess clinicopathological characteristics of primary gastro-entero-pancreatic poorly differentiated neuroendocrine carcinomas (GEP-PDNECAs) and evaluate overall survival in patients treated with systemic platinum and etoposide therapy.

Methods:

A detailed retrospective review of clinico-pathologic data (1999-2009) on 68 consecutive adult patients with primary GEP-PDNECAs was carried out, from H Lee Moffit Cancer Center and Research Institute, Tampa, Florida; USA, based on electronic patient records, specialty consultation files, tumor registry, social security index and pathology archives. All available tumor slides were reviewed and subtyped by neuro-endocrine pathologists. Clinicopathologic data and patient survival were analyzed.

Results:

Of 68 patients 41 were males and 27 females with a mean age of 42 years (range: 25-76 years). Regarding the site of origin, 39 patients were of the colorectal location, 19 from the pancreas, 04 from small intestines, 03 from stomach and 03 were multi-focal from colon, small intestine and pancreas. Sixty three of 68 (93%) patients presented with lymph node/distant metastases. Of 68 tumors 37 (54%) were classified as small cell carcinoma (SCCA), 16 (24%) large cell carcinoma (LCCA), 5 (7%) mixed small and large cell (MSLCCA) and 10 (15%) poorly differentiated carcinoma with neuroendocrine features (PDCA-NEF). Neuroendocrine differentiation was confirmed by positivity for chromogranin in 38/65 (55%), synaptophysin in 62/67 (92%) and CD56 in 17/21 (81%) cases. One neuroendocrine marker was positive in 22/68 (32%), 2 in 40/68 (59%) and all 3 were positive in 9/68 (13%) cases. Fifty-eight of 68 (85%) patients were treated with platinum and etoposide. Overall patient survival at 1, 3 5 and 10 years was 85%, 40%, 16% and 1.5% respectively. Patient survival was independent of age (r= 0.1022), sex (r= -0.909) and histologic tumor subtype (r=0.1028) (p= 0.128) but was related to distant metastases (r=0.306; p=0.0383).

Conclusions:

GEP-PDNECA occurred in many part of the GI tract, most commonly in the colorectal region. Positivity of neuroendocrine markers was variable, which helped to confirm neuro-endocrine differentiation and to avoid under-diagnosis of GEP-PDNECA, especially in metastatic setting. Overall prognosis of GEP-PDNECA patients following platinum and etoposide therapy in our series was relatively favorable but remained poor in the presence of distant metastases.

Layered double hydroxide eliminate embryotoxicity of chemotherapeutic drug through BMP-SMAD signaling pathway

Recent studies indicate that exogenous chemotherapy agents can cross the placenta barrier and cause fetal toxicity, while there exists barely alternative therapy for pregnant cancer patients. Here, we show a robust protective effect of layered double hydroxide (LDH) against etoposide (VP16) induced in vitro mouse embryonic stem cells (mESCs) toxicity and in vivo embryo developmental disorders. The nano-composite system (L-V) abrogated the original VP16 generated mitochondrial mediated mESCs toxicity totally, surprisingly maintained the pluripotency without leukemia inhibitory factor (LIF) and prevented the down-regulation of ectoderm marker expression during spontaneous embryoid bodies differentiation. Fetal growth retardation, the related placenta and skeletal structural abnormalities and long-term toxicity in the offspring were generated when pregnant mice exposed to VP16, while these detrimental effects were abolished when substituted with L-V. The different uterine drug accumulation of VP16 and L-V contributed to partly cause for the functional variation. And further transcriptome analysis confirmed developmental related BMP4-SMAD6 signaling pathway is of crucial importance. Our study revealed the devastating effects of VP16 on embryonic development and the toxicity-relieve method using nano-carrier system, which will provide important guidance for clinical application of LDH as alternative therapeutic system with minimal side effects for pregnant women diagnosed with cancer.

Novel deazaflavin tyrosyl-DNA phosphodiesterase 2 (TDP2) inhibitors

Tyrosyl-DNA phosphodiesterase 2 (TDP2) is a DNA repair enzyme that removes 5'-phosphotyrosyl blockages resulting from topoisomerase II (TOP2)-DNA cleavage complexes trapped by TOP2 inhibitors. TDP2 is a logical target for the development of therapeutics to complement existing treatments based on inhibition of TOP2. There is, however, no TDP2 inhibitor in clinical development at present. Of the reported TDP2 inhibitors, the deazaflavins are the most promising chemical class centered around the lead compound SV-5-153. Recently we reported new subtypes derived within the deazaflavin family with improved membrane permeability properties. In this work we characterize two representative analogues from two new deazaflavin subtypes based on their biochemical TDP2 inhibitory potency and drug-likeness. We demonstrate that the ZW-1288 derivative represents a promising direction for the development of deazaflavins as therapeutic agents. ZW-1288 exhibits potent inhibitory activity at low nanomolar concentrations against recombinant and cellular human TDP2 with profile similar to that of the parent analog SV-5-153 based on high resistance against murine TDP2 and human TDP2 mutated at residue L313H. While expressing weak cytotoxicity on its own, ZW-1288 potentiates the clinical TOP2 inhibitors etoposide (ETP) and mitoxantrone in human prostate DU145 and CCRF-CEM leukemia and chicken lymphoma DT40 cells while not impacting the activity of the topoisomerase I (TOP1) inhibitor camptothecin or the PARP inhibitor olaparib. ZW-1288 increases the uptake of ETP to a lesser extent than SV-5-153 and remained active in TDP2 knockout cells indicating that the deazaflavin TDP2 inhibitors have additional cellular effects that will have to be taken into account for their further development as TDP2 inhibitors.

Environmental risk assessment of widely used anticancer drugs (5-fluorouracil, cisplatin, etoposide, imatinib mesylate)

Anticancer drugs are among the most toxic chemicals, which are commercially produced; therefore, their release in aquatic ecosystems raised concerns in regard to potential adverse effects. This article describes the results of risk assessments concerning their environmental safety, which are based on data generated in the frame of a coordinated EU project ("Cytothreat"). Eight research institutions participated in the project and four widely used anticancer drugs with different mechanisms of therapeutic action (5-fluorouracil 5FU, cisplatin CDDP, imatinib mesylate IM and etoposide ET) were tested in a variety of indicator organisms (cyanobacteria, algae, higher plants, rotifers, crustacea, fish and also in human and fish derived cell lines) in acute/subacute/chronic toxicity assays. Furthermore, genotoxic effects in micronucleus assays, single cell gel electrophoresis experiments and γH2AX tests were studied in plants, crustacea, fish and in various cell lines. We used the results to calculate the predicted no effect concentrations (PNEC) and risk quotients (RQ) by comparing PNEC with predicted environmental concentrations (PEC values) and measured concentrations (MEC) in wastewaters. The most sensitive species in experiments concerning acute toxic and long term effects were in general crustacea (daphnids) after chronic treatment the most pronounced effects were detected with IM followed by CDDP and 5FU. Comparisons between PNEC and PEC values indicate that it is unlikely that the release of these drugs in the aquatic environments leads to adverse effects (RQ values < 1). However, when the assessments were performed with MEC found in highly contaminated municipal wastewaters and hospital effluents, RQ values were obtained which are indicative for moderate adverse effects of IM. Calculations with data from genotoxicity experiments and PEC values are indicative for increased RQ values for all compounds except ET. The most sensitive species were fish (Danio rerio) which were highly responsive towards 5FU and daphnids which were sensitive towards CDDP and IM. When environmental data (from waste waters) were used for the calculations, high RQ values (>100) were obtained for CDDP and IM. These overall conclusions were not substantially altered when the effects of other frequently used cytostatic drugs and combined effects of mixtures of anticancer drugs were taken into consideration. The results of these assessments underline the importance of efficient removal of these chemicals by improved sewage treatment strategies and the need for further investigations of adverse the long term effects of cytostatics in aquatic biota as a consequence of damage of the genetic material in highly sensitive species.

Genetic and epigenetic modifications induced by chemotherapeutic drugs: human amniotic fluid stem cells as an in-vitro model

BACKGROUND

Bleomycin, etoposide and cisplatin (BEP) are three chemotherapeutic agents widely used individually or in combination with each other or other chemotherapeutic agents in the treatment of various cancers. These chemotherapeutic agents are cytotoxic; hence, along with killing cancerous cells, they also damage stem cell pools in the body, which causes various negative effects on patients. The epigenetic changes due to the individual action of BEP on stem cells are largely unknown.

METHODS

Human amniotic fluid stem cells (hAFSCs) were treated with our in-vitro standardized dosages of BEP individually, for seven days. The cells were harvested after the treatment and extraction of DNA and RNA were performed. Real-time PCR and flow cytometry were conducted for cell markers analysis. The global DNA methylation was quantified using 5mC specific kit and promoter and CpG methylation % through bisulfite conversion and pyrosequencing. Micro- RNAs (miRNAs) were quantified with real-time qPCR.

RESULTS

The cytotoxic nature of BEP was observed even at low dosages throughout the experiment. We also investigated the change in the expression of various pluripotent and germline markers and found a significant change in the properties of the cells after the treatments. The methylation of DNA at global, promoter and individual CpG levels largely get fluctuated due to the BEP treatment. Several tested miRNAs showed differential expression. No positive correlation between mRNA and protein expression was observed for some markers.

CONCLUSION

Cytotoxic chemotherapeutic agents such as BEP were found to alter stem cell properties of hAFSCs. Different methylation profiles change dynamically, which may explain such changes in cellular properties. Data also suggests that the fate of hAFSCs after treatment may depend upon the interplay between the miRNAs. Finally, our results demonstrate that hAFSCs might prove to be a suitable in-vitro model of stem cells to predict genetic and epigenetic modification due to the action of various drugs.

Etoposide Combined with FLAG Salvage Therapy Is Effective in Multiple Relapsed/Refractory Acute Myeloid leukemia

Managing acute myeloid leukemia (AML) is often hampered by repeated failure to achieve complete remission as well as recurrent relapse that causes an emergent need for alternative salvage therapies. The efficacy of most salvage therapies is based on anthracycline combinations. In highly pretreated patients who are not eligible for anthracycline-based protocols therapeutic alternatives are limited. For this particular group we evaluated the efficacy and safety of fludarabine, cytarabine, granulocyte colony-stimulating factor (FLAG) in combination with etoposide (FLAG-Eto) in 36 patients. The complete remission rate (CR) was 25.7% with a median overall survival of 6 months (95% CI 4.5-7.7). The median disease-free survival for CR/CRi/MLFS (CR/CR with incomplete he-matological recovery/morphologic leukemia-free state) patients was 8 months (95% CI 0.6-15.5). The mortality rate on day 30 was 8% and increased on day 60 to 17%. Our results show meaningful anti-leukemic activity of the FLAG-Eto regimen with a moderate toxicity profile in heavily pretreated relapsed/refractory AML patients enabling consolidating allogeneic stem cell transplantation.

Inhibition of DNA-PK potentiates the synergistic effect of NK314 and etoposide combination on human glioblastoma cells

Etoposide (VP-16) is the topoisomerase 2 (Top2) inhibitor used for treating of glioma patients however at high dose with serious side effects. It induces DNA double-strand breaks (DSBs). These DNA lesions are repaired by non-homologous DNA end joining (NHEJ) mediated by DNA-dependent protein kinase (DNA-PK). One possible approach to decrease the toxicity of etoposide is to reduce the dose while maintaining the anticancer potential. It could be achieved through combined therapy with other anticancer drugs. We have assumed that this objective can be obtained by (1) a parallel topo2 α inhibition and (2) sensitization of cancer cells to DSBs. In this work we investigated the effect of two Top2 inhibitors NK314 and VP-16 in glioma cell lines (MO59 K and MO59 J) sensitized by DNA-PK inhibitor, NU7441. Cytotoxic effect of VP-16, NK314 alone and in combination on human glioblastoma cell lines, was assessed by a colorimetric assay. Genotoxic effect of anticancer drugs in combination with NU7441 was assessed by comet assay. Cell cycle distribution and apoptosis were analysed by flow cytometry. Compared with VP-16 or NK314 alone, the combined treatment significantly inhibited cell proliferation. Combination treatment was associated with a strong accumulation of DSBs, modulated cell cycle phases distribution and apoptotic cell death. NU7441 potentiated these effects and additionally postponed DNA repair. Our findings suggest that NK314 could overcome resistance of MO59 cells to VP-16 and NU7441 could serve as sensitizer to VP-16/NK314 combined treatment. The combined tripartite approach of chemotherapy could reduce the overall toxicity associated with each individual therapy, while concomitantly enhancing the anticancer effect to treat human glioma cells. Thus, the use of a tripartite combinatorial approach could be promising and more efficacious than mono therapy or dual therapy to treat and increase the survival of the glioblastoma patients.