Toxicities of four anti-neoplastic drugs and their binary mixtures tested on the green alga Pseudokirchneriella subcapitata and the cyanobacterium Synechococcus leopoliensis

The residues of anti-neoplastic drugs are new and emerging pollutants in aquatic environments. This is not only because of their increasing use, but also because due to their mechanisms of action, they belong to a group of particularly dangerous compounds. However, information on their ecotoxicological properties is very limited. We tested the toxicities of four anti-neoplastic drugs with different mechanisms of action (5-fluorouracil [5-FU], cisplatin [CDDP], etoposide [ET], and imatinib mesylate [IM]), and some of their binary mixtures, against two phytoplankton species: the alga Pseudokirchneriella subcapitata, and the cyanobacterium Synechococcus leopoliensis. These four drugs showed different toxic potential, and the two species examined also showed differences in their susceptibilities towards the tested drugs and their mixtures. With P. subcapitata, the most toxic of these drugs was 5-FU (EC50, 0.13 mg/L), followed by CDDP (EC50, 1.52 mg/L), IM (EC50, 2.29 mg/L), and the least toxic, ET (EC50, 30.43 mg/L). With S. leopoliensis, the most toxic was CDDP (EC50, 0.67 mg/L), followed by 5-FU (EC50, 1.20 mg/L) and IM (EC50, 5.36 mg/L), while ET was not toxic up to 351 mg/L. The toxicities of the binary mixtures tested (5-FU + CDDP, 5-FU + IM, CDDP + ET) were predicted by the concepts of 'concentration addition' and 'independent action', and are compared to the experimentally determined toxicities. The measured toxicity of 5-FU + CDDP with P. subcapitata and S. leopoliensis was higher than that predicted, while the measured toxicity of CDDP + ET with both species was lower than that predicted. The measured toxicity of 5-FU + IM with P. subcapitata was higher, and with S. leopoliensis was lower, than that predicted. These data show that these mixtures can have compound-specific and species-specific synergistic or antagonistic effects, and they suggest that single compound toxicity data are not sufficient for the prediction of the aquatic toxicities of such anticancer drug mixtures.

A role for orexin in cytotoxic chemotherapy-induced fatigue

Fatigue is the most common symptom related to cytotoxic chemotherapeutic treatment of cancer. Peripheral inflammation associated with cytotoxic chemotherapy is likely a causal factor of fatigue. The neural mechanisms by which cytotoxic chemotherapy associated inflammation induces fatigue behavior are not known. This lack of knowledge hinders development of interventions to reduce or prevent this disabling symptom. Infection induced fatigue/lethargy in rodents is mediated by suppression of hypothalamic orexin activity. Orexin is critical for maintaining wakefulness and motivated behavior. Though there are differences between infection and cytotoxic chemotherapy in some symptoms, both induce peripheral inflammation and fatigue. Based on these similarities we hypothesized that cytotoxic chemotherapy induces fatigue by disrupting orexin neuron activity. We found that a single dose of a cytotoxic chemotherapy cocktail (cyclophosphamide, adriamycin, 5-fluorouracil - CAF) induced fatigue/lethargy in mice and rats as evidenced by a significant decline in voluntary locomotor activity measured by telemetry. CAF induced inflammatory gene expression - IL-1R1 (p<0.001), IL-6 (p<0.01), TNFα (p<0.01), and MCP-1 (p<0.05) - in the rodent hypothalamus 6-24h after treatment during maximum fatigue/lethargy. CAF decreased orexin neuron activity as reflected by decreased nuclear cFos localization in orexin neurons 24h after treatment (p<0.05) and by decreased orexin-A in cerebrospinal fluid 16 h after treatment (p<0.001). Most importantly, we found that central administration of 1 μg orexin-A restored activity in CAF-treated rats (p<0.05). These results demonstrate that cytotoxic chemotherapy induces hypothalamic inflammation and that suppression of hypothalamic orexin neuron activity has a causal role in cytotoxic chemotherapy-induced fatigue in rodents.

Curcumin chemosensitizes 5-fluorouracil resistant MMR-deficient human colon cancer cells in high density cultures

Objective

Treatment of colorectal cancer (CRC) remains a clinical challenge, as more than 15% of patients are resistant to 5-Fluorouracil (5-FU)-based chemotherapeutic regimens, and tumor recurrence rates can be as high as 50–60%. Cancer stem cells (CSC) are capable of surviving conventional chemotherapies that permits regeneration of original tumors. Therefore, we investigated the effectiveness of 5-FU and plant polyphenol (curcumin) in context of DNA mismatch repair (MMR) status and CSC activity in 3D cultures of CRC cells.

Methods

High density 3D cultures of CRC cell lines HCT116, HCT116+ch3 (complemented with chromosome 3) and their corresponding isogenic 5-FU-chemo-resistant derivative clones (HCT116R, HCT116+ch3R) were treated with 5-FU either without or with curcumin in time- and dose-dependent assays.

Results

Pre-treatment with curcumin significantly enhanced the effect of 5-FU on HCT116R and HCR116+ch3R cells, in contrast to 5-FU alone as evidenced by increased disintegration of colonospheres, enhanced apoptosis and by inhibiting their growth. Curcumin and/or 5-FU strongly affected MMR-deficient CRC cells in high density cultures, however MMR-proficient CRC cells were more sensitive. These effects of curcumin in enhancing chemosensitivity to 5-FU were further supported by its ability to effectively suppress CSC pools as evidenced by decreased number of CSC marker positive cells, highlighting the suitability of this 3D culture model for evaluating CSC marker expression in a close to vivo setting.

Conclusion

Our results illustrate novel and previously unrecognized effects of curcumin in enhancing chemosensitization to 5-FU-based chemotherapy on DNA MMR-deficient and their chemo-resistant counterparts by targeting the CSC sub-population. (246 words in abstract).

Assessment of genotoxic effects in nurses handling cytostatic drugs

Several antineoplastic drugs have been classified as carcinogens by the International Agency for Research on Cancer (IARC) on the basis of epidemiological findings, animal carcinogenicity data, and outcomes of in vitro genotoxicity studies. 5-Fluorouracil (5-FU), which is easily absorbed through the skin, is the most frequently used antineoplastic agent in Portuguese hospitals and therefore may be used as an indicator of surface contamination. The aims of the present investigation were to (1) examine surface contamination by 5-FU and (2) assess the genotoxic risk using cytokinesis-block micronucleus assay in nurses from two Portuguese hospitals. The study consisted of 2 groups: 27 nurses occupationally exposed to cytostatic agents (cases) and 111 unexposed individuals (controls). Peripheral blood lymphocytes (PBL) were collected in order to measure micronuclei (MN) in both groups. Hospital B showed a higher numerical level of contamination but not significantly different from Hospital A. However; Hospital A presented the highest value of contamination and also a higher proportion of contaminated samples. The mean frequency of MN was significantly higher in exposed workers compared with controls. No significant differences were found among MN levels between the two hospitals. The analysis of confounding factors showed that age is a significant variable in MN frequency occurrence. Data suggest that there is a potential genotoxic damage related to occupational exposure to cytostatic drugs in oncology nurses.

Mahanine synergistically enhances cytotoxicity of 5-fluorouracil through ROS-mediated activation of PTEN and p53/p73 in colon carcinoma

5-Fluorouracil (5-FU) alone or in combination with other drugs is the main basis of chemotherapeutic treatment in colorectal cancer although patients with microsatellite instability generally show resistance to 5-FU treatment. The present investigation is focussed on the mechanistic insight of a pure herbal carbazole alkaloid, mahanine, as a single or in combination with 5-FU in colon cancer. We demonstrated that mahanine-induced apoptosis involved reactive oxygen species (ROS)-mediated nuclear accumulation of PTEN and its interaction with p53/p73. Mahanine and 5-FU in combination exerted synergistic inhibitory effect on cell viability. This combination also enhanced ROS production, increased tumour suppressor proteins and suppressed chemo-migration. Taken together, our results revealed that mahanine can be a potential chemotherapeutic agent with efficacy to reduce the concentration of toxic 5-FU in colon cancer.

Correlation between dihydropyrimidine dehydrogenase and efficacy and toxicity of fluoropyrimidine drugs

At present, fluoropyrimidine, based on 5-fluorouracil (5-FU), remains one of the most frequently prescribed chemotherapeutics drugs for the treatment of cancer. Dihydropyrimidine dehydrogenase (DPD) is the rate-limiting enzyme in the catabolism of 5-FU, and DPD enzymatic activities are usually varied dramatically from individual to individual, including both the intrapatient differences and the interpatient variability. There is a certain correlation between the DPD activity and efficacy and toxicity following the administration of fluoropyrimidine drugs. Partial or complete loss of DPD activity can lead to serious or even lethal toxicity. In this article, we review the relationship between DPD activity and efficacy and toxicity following the administration of fluoropyrimidine drugs, and also the structure, function, and characteristics of DPD. We report here that measurement of DPD activity may become a strategy and be paid much attention to predict the efficacy and toxicity prior to starting a fluoropyrimidine-based therapy.

Protective effect of curcumin on chemotherapy-induced intestinal dysfunction

OBJECTIVE

Chemotherapy is one of most important treatments for human cancers. However, side effects such as intestine dysfunction significantly impaired its clinical efficacy. This study aimed to investigate the protective effect of Curcumin on chemotherapy-induced intestinal dysfunction in rats.

METHODS

Sixty healthy Wistar rats were randomly divided into control group (normal saline), 5-FU group and 5-FU+Curcumin group. The weight, serum level of endotoxin, DAO and D-lactate were determined. The pathological change of intestinal mucosa structure was studied under light microscopy and electron microscopy. The expression of Bax, Bcl-2 and Caspase-3 were assessed by immunohistochemical staining.

RESULTS

The Curcumin intragastrically administrated obviously reduced 5-FU-induced weight-loss. 5-FU induced dramatic increase of serum endotoxin, D-lactate and D-Amino-Acid Oxidase (DAO) that were significantly reversed by Curcumin treatment. Meanwhile, 5-FU-induced-damage to intestinal mucosa structure was markedly recovered by Curcumin. The expression of Bax and Caspase-3 were dramatically increased after 5-FU treatment (p<0.01) and Curcumin treatment significantly reduced Bax expression (p<0.05) but had only a moderate effect on reducing caspase-3 expression (p>0.05). Interestingly, Bcl-2 expression was low in control group but increased after 5-FU treatment (p>0.05) and Curcumin treatment further stimulated Bcl-2 expression (p<0.05).

CONCLUSIONS

Curcumin can significantly reverse chemotherapy-induced weight-loss, increase of serum endotoxin, D-lactate and DAO and damage to intestinal mucosa structure. Curcumin also reduced the expression of pro-apoptotic Bax but stimulated anti-apoptotic Bcl-2 to attenuate 5-FU-induced apoptosis of intestinal epithelial cells. The clinical administration of Curcumin may improve chemotherapy-induced intestinal dysfunction, thus increasing the clinical efficacy of chemotherapy.

Treatment of colorectal cancer using a combination of liposomal irinotecan (Irinophore C™) and 5-fluorouracil

Purpose

To investigate the use of liposomal irinotecan (Irinophore C™) plus or minus 5-fluorouracil (5-FU) for the treatment of colorectal cancer.

Experimental Design

The effect of irinotecan (IRI) and/or 5-FU exposure times on cytotoxicity was assessed in vitro against HT-29 or LS174T human colon carcinoma cells. The pharmacokinetics and biodistribution of Irinophore C™ (IrC™) and 5-FU, administered alone or in combination, were compared in vivo. A subcutaneous model of HT-29 human colorectal cancer in Rag2-M mice was utilized to assess the efficacy of IrC™ alone, and in combination with 5-FU.

Results

The cytotoxicity of IRI and 5-FU were strongly dependent on exposure time. Synergistic interactions were observed following prolonged exposure to IRI/5-FU combinations. Pharmacokinetics/biodistribution studies demonstrated that the 5-FU elimination rate was decreased significantly when 5-FU was co-administered intravenously with IrC™, versus alone. Significant decreases in 5-FU elimination were also observed in plasma, with an associated increase of 5-FU in some tissues when 5-FU was given by intraperitoneal injection and IrC™ was given intravenously. The elimination of IrC™ was not significantly different when administered alone or in combination with 5-FU. Therapeutic studies demonstrated that single agent IrC™ was significantly more effective than the combination of IRI/5-FU; surprisingly, IrC™/5-FU combinations were no more effective than IrC™ alone. The administration of combinations of 5-FU (16 mg/kg) and IrC™ (60 mg IRI/kg) showed increased toxicity when compared to IrC™ alone. Treatment with IrC™ alone (60 mg IRI/kg) delayed the time required for a 5-fold increase in initial tumor volume to day 49, compared to day 23 for controls. When IrC™ (40 mg IRI/kg) was used in combination with 5-FU (16 mg/kg), the time to increase tumor volume 5-fold was 43 days, which was comparable to that achieved when using IrC™ alone (40 mg IRI/kg).

Conclusions

Single agent IrC™ was well tolerated and has significant therapeutic potential. IrC™ may be a suitable replacement for IRI treatment, but its use with free 5-FU is complicated by IrC™-engendered changes in 5-FU pharmacokinetics/biodistribution which are associated with increased toxicity when using the combination.

An in vivo functional screen uncovers miR-150-mediated regulation of hematopoietic injury response

Hematopoietic stem and progenitor cells are often undesired targets of chemotherapies, leading to hematopoietic suppression requiring careful clinical management. Whether microRNAs control hematopoietic injury response is largely unknown. We report an in vivo gain-of-function screen and the identification of miR-150 as an inhibitor of hematopoietic recovery upon 5-fluorouracil-induced injury. Utilizing a bone marrow transplant model with a barcoded microRNA library, we screened for barcode abundance in peripheral blood of recipient mice before and after 5-fluorouracil treatment. Overexpression of screen-candidate miR-150 resulted in significantly slowed recovery rates across major blood lineages, with associated impairment of bone marrow clonogenic potential. Conversely, platelets and myeloid cells from miR-150 null marrow recovered faster after 5-fluorouracil treatment. Heterozygous knockout of c-myb, a conserved target of miR-150, partially phenocopied miR-150-forced expression. Our data highlight the role of microRNAs in controlling hematopoietic injury response and demonstrate the power of in vivo functional screens for studying microRNAs in normal tissue physiology.

Ursolic acid inhibits growth and metastasis of human colorectal cancer in an orthotopic nude mouse model by targeting multiple cell signaling pathways: chemosensitization with capecitabine

PURPOSE

Development of chemoresistance, poor prognosis, and metastasis often renders the current treatments for colorectal cancer (CRC) ineffective. Whether ursolic acid, a component of numerous medicinal plants, either alone or in combination with capecitabine, can inhibit the growth and metastasis of human CRC was investigated.

EXPERIMENTAL DESIGN

The effect of ursolic acid on proliferation of CRC cell lines was examined by mitochondrial dye uptake assay, apoptosis by esterase staining, NF-κB activation by DNA-binding assay, and protein expression by Western blot. The effect of ursolic acid on the growth and chemosensitization was also examined in orthotopically implanted CRC in nude mice.

RESULTS

We found that ursolic acid inhibited the proliferation of different colon cancer cell lines. This is correlated with inhibition of constitutive NF-κB activation and downregulation of cell survival (Bcl-xL, Bcl-2, cFLIP, and survivin), proliferative (cyclin D1), and metastatic (MMP-9, VEGF, and ICAM-1) proteins. When examined in an orthotopic nude mouse model, ursolic acid significantly inhibited tumor volume, ascites formation, and distant organ metastasis, and this effect was enhanced with capecitabine. Immunohistochemistry of tumor tissue indicated that ursolic acid downregulated biomarkers of proliferation (Ki-67) and microvessel density (CD31). This effect was accompanied by suppression of NF-κB, STAT3, and β-catenin. In addition, ursolic acid suppressed EGF receptor (EGFR) and induced p53 and p21 expression. We also observed bioavailability of ursolic acid in the serum and tissue of animals.

CONCLUSION

Overall, our results show that ursolic acid can inhibit the growth and metastasis of CRC and further enhance the therapeutic effects of capecitabine through the suppression of multiple biomarkers linked to inflammation, proliferation, invasion, angiogenesis, and metastasis.

Rapid Detection of the DPYD IVS14+1G>A Mutation for Screening Patients to Prevent Fluorouracil-Related Toxicity

BACKGROUND

Deficiency of dihydropyrimidine dehydrogenase (DPD) has been linked to severe or lethal fluorouracil (FU)-related toxicity. The most prominent mutation in the DPYD gene is the IVS14+1G>A mutation, which causes skipping of exon 14 in the messenger RNA (mRNA) and results in DPD enzyme deficiency. Several methods have been described to detect this mutation, but all are labor intensive and low throughput. OBJECTIVE Our aim was to develop a high-throughput real-time PCR assay to screen patients for the IVS14+1G>A mutation.

METHODS

Primers and probes were developed and several reaction conditions were tested. In total, 165 individuals were screened for this mutation, with DNA sequencing as a reference method.

RESULTS

Results of the real-time PCR assay and DNA sequencing were 100% identical. In total, eight heterozygous individuals were identified, of which six were patients with severe FU-related toxicity after FU or capecitabine treatment and two were healthy volunteers.

CONCLUSION

This new real-time PCR assay with a high throughput is particularly suitable for large-scale screening for the IVS14+1G>A mutation in patients selected for treatment with fluoropyrimidines in order to prevent severe FU-related toxicity.

[Expressions of orotate phosphoribosyltransferase in colorectal carcinoma and its correlations with toxicities of chemotherapy]

OBJECTIVE

To investigate the expression of orotate phosphoribosyltransferase (OPRT) in colorectal carcinoma and analyze its correlations with the toxicities of chemotherapy.

METHODS

The expression of OPRT mRNA was detected using RT-PCR in colorectal carcinoma tissues and paired adjacent normal tissues from 58 patients receiving FOLFOX6 regimen chemotherapy. The toxicities of the chemotherapy were recorded, and the correlations between OPRT mRNA expression and the toxicities were analyzed.

RESULTS

OPRT mRNA expression was significantly higher in the tumor tissues than in the corresponding normal tissues (P=0.001), but OPRT expression in the tumor tissues was not correlated with the toxicities of the chemotherapy (P>0.05). OPRT level in the normal tissues showed a significant positive correlation with the occurrence of diarrhea in these cases (P=0.013).

CONCLUSION

OPRT expression in colorectal carcinoma tissues is not correlated with the toxicities of 5-FU-based regimen, but OPRT expression in the normal tissues can help predict the toxicities associated with 5-FU.

Dietary emu oil supplementation suppresses 5-fluorouracil chemotherapy-induced inflammation, osteoclast formation, and bone loss

Cancer chemotherapy can cause osteopenia or osteoporosis, and yet the underlying mechanisms remain unclear, and currently, no preventative treatments are available. This study investigated damaging effects of 5-fluorouracil (5-FU) on histological, cellular, and molecular changes in the tibial metaphysis and potential protective benefits of emu oil (EO), which is known to possess a potent anti-inflammatory property. Female dark agouti rats were gavaged orally with EO or water (1 ml·day(-1)·rat(-1)) for 1 wk before a single ip injection of 5-FU (150 mg/kg) or saline (Sal) was given. The treatment groups were H(2)O + Sal, H(2)O + 5-FU, EO + 5-FU, and EO + Sal. Oral gavage was given throughout the whole period up to 1 day before euthanasia (days 3, 4, and 5 post-5-FU). Histological analysis showed that H(2)O + 5-FU significantly reduced heights of primary spongiosa on days 3 and 5 and trabecular bone volume of secondary spongiosa on days 3 and 4. It reduced density of osteoblasts slightly and caused an increase in the density of osteoclasts on trabecular bone surface on day 4. EO supplementation prevented reduction of osteoblasts and induction of osteoclasts and bone loss caused by 5-FU. Gene expression studies confirmed an inhibitory effect of EO on osteoclasts since it suppressed 5-FU-induced expression of proinflammatory and osteoclastogenic cytokine TNFα, osteoclast marker receptor activator of nuclear factor-κB, and osteoclast-associated receptor. Therefore, this study demonstrated that EO can counter 5-FU chemotherapy-induced inflammation in bone, preserve osteoblasts, suppress osteoclast formation, and potentially be useful in preventing 5-FU chemotherapy-induced bone loss.

Efficient inhibition of colorectal peritoneal carcinomatosis by drug loaded micelles in thermosensitive hydrogel composites

In this work, we aim to develop a dual drug delivery system (DDDS) of self-assembled micelles in thermosensitive hydrogel composite to deliver hydrophilic and hydrophobic drugs simultaneously for colorectal peritoneal carcinomatosis (CRPC) therapy. In our previous studies, we found that poly(ε-caprolactone)-poly(ethylene glycol)-poly(ε-caprolactone) (PCEC) copolymers with different molecular weight and PEG/PCL ratio could be administered to form micelles or thermosensitive hydrogels, respectively. Therefore, the DDDS was constructed from paclitaxel (PTX) encapsulated PCEC micelles (PTX-micelles) and a fluorouracil (Fu) loaded thermosensitive PCEC hydrogel (Fu-hydrogel). PTX-micelles were prepared by self-assembly of biodegradable PCEC copolymer (M(n) = 3700) and PTX without using any surfactants or excipients. Meanwhile, biodegradable and injectable thermosensitive Fu-hydrogel (M(n) = 3000) with a lower sol-gel transition temperature at around physiological temperature was also prepared. The obtained PTX-micelles in thermosensitive Fu-hydrogel (PTX-micelles-Fu-hydrogel) composite is a free-flowing sol at ambient temperature and rapidly turned into a non-flowing gel at physiological temperature. In addition, the results of cytotoxicity, hemolytic study, and acute toxicity evaluation suggested that the PTX-micelles-Fu-hydrogel was non-toxic and biocompatible. In vitro release behaviors of PTX-micelles-Fu-hydrogel indicated that both PTX and Fu have a sustained release behavior. Furthermore, intraperitoneal application of PTX-micelles-Fu-hydrogel effectively inhibited growth and metastasis of CT26 peritoneal carcinomatosis in vivo (p < 0.001), and induced a stronger antitumor effect than that of Taxol® plus Fu (p < 0.001). The pharmacokinetic study indicated that PTX-micelles-Fu-hydrogel significantly increased PTX and Fu concentration and residence time in peritoneal fluids compared with Taxol® plus Fu group. Thus, the results suggested the micelles-hydrogel DDDS may have great potential clinical applications.

5-Fluorouracil accumulation in green microalgae and its biogenetic transfer into ciliate protozoan

The study has demonstrated that anticancer drug 5-fluorouracil causes acute toxicity and interferes with the growth of green microalgae, Scenedesmus vacuolatus. It accumulates in microalgae biomass with bioaccumulation factor of 1.84 × 10(4) and further integrates into the DNA and RNA of microalgae. In addition, the labelled microalgae genome is transferred into protozoan Tetrahymena pyriformis on feeding and is retained in the food vacuoles of predator organisms. This biotransfer of labelled 5-fluorouracil via genomic material was evaluated using radioactivity in Tetrahymena cell pellets though radioactivity did not detect anticancer drug in the genome of the predator organism.

5-Fluorouracil induced intestinal mucositis via nuclear factor-κB activation by transcriptomic analysis and in vivo bioluminescence imaging

5-Fluorouracil (5-FU) is a commonly used drug for the treatment of malignant cancers. However, approximately 80% of patients undergoing 5-FU treatment suffer from gastrointestinal mucositis. The aim of this report was to identify the drug target for the 5-FU-induced intestinal mucositis. 5-FU-induced intestinal mucositis was established by intraperitoneally administering mice with 100 mg/kg 5-FU. Network analysis of gene expression profile and bioluminescent imaging were applied to identify the critical molecule associated with 5-FU-induced mucositis. Our data showed that 5-FU induced inflammation in the small intestine, characterized by the increased intestinal wall thickness and crypt length, the decreased villus height, and the increased myeloperoxidase activity in tissues and proinflammatory cytokine production in sera. Network analysis of 5-FU-affected genes by transcriptomic tool showed that the expression of genes was regulated by nuclear factor-κB (NF-κB), and NF-κB was the central molecule in the 5-FU-regulated biological network. NF-κB activity was activated by 5-FU in the intestine, which was judged by in vivo bioluminescence imaging and immunohistochemical staining. However, 5-aminosalicylic acid (5-ASA) inhibited 5-FU-induced NF-κB activation and proinflammatory cytokine production. Moreover, 5-FU-induced histological changes were improved by 5-ASA. In conclusion, our findings suggested that NF-κB was the critical molecule associated with the pathogenesis of 5-FU-induced mucositis, and inhibition of NF-κB activity ameliorated the mucosal damage caused by 5-FU.

An investigation of oxidative DNA damage in pharmacy technicians exposed to antineoplastic drugs in two Chinese hospitals using the urinary 8-OHdG assay

OBJECTIVE

To investigate oxidative DNA damage in pharmacy technicians preparing antineoplastic drugs at the PIVAS (Pharmacy Intravenous Admixture Service) in two Chinese hospitals.

METHODS

Urinary 8-OHdG served as a biomarker. 5-Fluorouracil (5-FU) concentrations in air, masks and gloves were determined. The spill exposure of each PIVAS technician to antineoplastic drugs was investigated. Eighty subjects were divided into exposed group I, II, and control group I, II.

RESULTS

5-FU concentration ratios for gloves and masks in exposed group I were significantly higher than those in exposed group II (P<0.05 or P<0.01). The average urinary 8-OHdG concentrations in exposed group I, control group I, exposed group II, and control group II were 14.69±0.93, 10.68±1.07, 10.57±0.55, and 11.96±0.73 ng/mg Cr, respectively. Urinary 8-OHdG concentration in exposed group I was significantly higher than that in control group I or that in exposed group II (P<0.01). There was a significant correlation between urinary 8-OHdG concentrations and spill frequencies per technician (P<0.01).

CONCLUSION

There was detectable oxidative DNA damage in PIVAS technicians exposed to antineoplastic drugs. This oxidative DNA damage may be associated with their spill exposure experience and contamination of their personal protective equipment.

Cytotoxicity and genotoxicity of capecitabine in head and neck cancer and normal cells

The interaction between a chemical and a cell may strongly depend on whether this cell is normal or pathological. Side effects of anticancer drugs may sometimes overcome their benefit action, so it is important to investigate their effect in both the target and normal cells. Capecitabine (Xeloda, CAP), a prodrug of 5-fluorouracil, is mainly used in colon cancer, but little is known about its action in head and neck cancer. We compared the cyto- and genotoxicity of CAP in head and neck HTB-43 cells and normal human lymphocytes by comet assay and flow cytometry. CAP at concentration up to 50 μM significantly decreased the viability of the cancer cells, whereas it did not affect normal lymphocytes. The drug did not interact with isolated plasmid DNA, but it damaged DNA in both cancer and normal cells. However, the extent of the damage in the former was much higher than in the latter. CAP induced apoptosis in the cancer cells, but not in normal lymphocytes. Pre-treatment of the cells with the nitrone spin traps α-(4-pyridil-1-oxide)-N-tert-butylnitrone and N-tert-butyl-α-phenylnitrone decreased the extent of CAP induced DNA damage, suggesting that free radicals may be involved in the formation of DNA lesions induced by CAP. The drug evoked an increase in the G0/G1 cell population accompanied by a decrease in the S cell population. CAP may evoke a pronounced cyto- and genotoxic effects in head and neck cancer cells, whereas it may or may not induce such effects in normal cells to far lesser extent.

[Evaluation in vitro of the cardiotoxic effects of 5-fluorouracil for the prevention of cardiovascular damage in health workers occupationally exposed]

The occupational exposure to antineoplastic drugs in health care workers determines a risk of absorption through inhalation of vapors or skin contact with drops. Even if many data confirm the cardiotoxicity of anthracyclines, is not clear the evidence of cytotoxicity of 5-Fluorouracil, thoug in a percent of patients receiving this chemotherapy, there is the presence of heart pain, aspecific ECG disorders and induction of coronary disease. This experimental study wants to analyze on the H9c2 cardiomyocyte cell model the effects of 5-Fluorouracil, commonly used in hospital realities of the South Italy, for the prevention of the possible cardiovascular damage in workers occupationally exposed.

Transdermal delivery of an anti-cancer drug via w/o emulsions based on alkyl polyglycosides and lecithin: design, characterization, and in vivo evaluation of the possible irritation potential in rats

The purpose of this work was to develop w/o emulsions that could be safely used to promote transdermal delivery of 5-fluorouracil (5-FU). Two pseudo-ternary phase diagrams comprising oleoyl-macrogol glycerides, water, and a surfactant/co-surfactant (S/CoS) mixture of lecithin, ethanol, and either coco glucoside or decyl glucoside were investigated for their potential to develop promising 5-FU emulsions. Six systems were selected and subjected to thermodynamic stability tests; heat-cool cycles, centrifugation, and finally freeze-thaw cycles. All systems passed the challenges and were characterized for transmission electron microscopy, droplet size, rheological behavior, pH, and transdermal permeation through newly born mice skin in Franz diffusion cells. The systems had spherical droplets ranging in diameter from 1.81 to 2.97 μm, pH values ranging from 7.50 to 8.49 and possessed Newtonian flow. A significant (P<0.05) increase in 5-FU permeability parameters as steady-state flux, permeability coefficient was achieved with formula B5 comprising water (5% w/w), S/CoS mixture of lecithin/ethanol/decyl glucoside (14.67:12.15:18.18% w/w, respectively) and oleoyl-macrogol glycerides (50% w/w). When applied to shaved rat skin, this system was well tolerated with only moderate skin irritation that was recovered within 12 h. Indeed, minor histopathologic changes were observed after 5-day treatment. Further studies should be carried out, in the future, to investigate the potentiality of this promising system to promote transdermal delivery of 5-FU through human skin.

Mouse embryonic stem cell adherent cell differentiation and cytotoxicity (ACDC) assay

An adherent cell differentiation and cytotoxicity (ACDC) assay was developed using pluripotent J1 mouse embryonic stem cells (mESCs). Adherent mESCs were used to evaluate chemical-induced effects on both stem cell viability and differentiation using an in-cell western technique after a 9-day culture. DRAQ5/Sapphire700 stains were used to quantify cell number. Myosin heavy chain protein was used as a marker of cardiomyocyte differentiation and was corrected for cell number, thereby separating cytotoxicity and effects on differentiation. Acetic acid, 5-fluorouracil and bromochloroacetic acid were evaluated using the embryonic stem cell test and ACDC assay. Both systems distinguish the relative potencies of these compounds. TaqMan low-density arrays were used to characterize the time course of differentiation and effects of chemical exposure on multiple differentiation gene markers. The ACDC assay is a technique that can be used to evaluate the effects of xenobiotics on mESC differentiation and cell number using a single assay.

[Establishment of embryonic stem cell for evaluation of development neurotoxicity and test the validation of embryonic stem cell]

OBJECTIVE

To establish embryonic stem cell (EST) for evaluation of developmental neurontoxicity and test the validation of EST.

METHODS

RT-PCR method was used to study the influence of fluorouracil (5-FU), diphenylhydantoin (DPH) and Penicillin G at the different concentrations on neuron cells with nestin expression that differentiate from embryonic stem cells (ES). With the results of cells viability (ES and BALB/c) assessed by MTT, the developmental neurotoxicty characteristics of 5-FU, DPH and Penicillin G may be identified clearly. RESULTS; The ID50 D3 nestin concentration of three embryotoxicants were 0.017, 49.4 and 1139 microg/ml. Penicillin G, DPH and 5-FU were discriminated as none-, weak- and strong- developmental neurotoxicity. CONCLUSION; Test compounds among three classes were discriminated correctly. The EST on developmental neurontoxicity could be applied to the safety evaluation in vitro.

Ecotoxicity and genotoxicity assessment of cytotoxic antineoplastic drugs and their metabolites

In spite of growing scientific concern about pharmaceuticals in the environment, there is still a lack of information especially with regard to their metabolites. The present study investigated ecotoxicity and genotoxicity of three widely used cytostatic agents 5-fluorouracil (5-FU), cytarabine (CYT) and gemcitabine (GemC) and their major human metabolites, i.e. alpha-fluoro-beta-alanine (FBAL), uracil-1-beta-D-arabinofuranoside (AraU) and 2',2'-difluorodeoxyuridine (dFdU), respectively. Effects were studied in acute immobilization and reproduction assays with crustacean Daphnia magna and growth inhibition tests with alga Desmodesmus subspicatus and bacteria Pseudomonas putida. Genotoxicity was tested with umu-test employing Salmonella choleraesius subsp. chol. Toxicity was relatively high at parent compounds with EC(50) values ranging from 44 microg L(-1) (5-fluorouracil in the P. putida test) to 200 mg L(-1) (cytarabine in D. magna acute test). In general, the most toxic compound was 5-FU. Studied metabolites showed low or no toxicity; only FBAL (metabolite of 5-FU) showed low toxicity to D. subspicatus and P. putida with EC(50) values 80 and 140 mg L(-1), respectively. All parent cytostatics showed genotoxicity with minimum genotoxic concentrations (MGC) ranging from 40 to 330 mg L(-1). From metabolites, only FBAL was genotoxic in high concentrations. To our knowledge, the present study provides some of the first ecotoxicity data for both cytostatics and their metabolites, which might further serve for serious evaluation of ecological risks. The observed EC(50) values within the microg L(-1) range were fairly close to concentrations reported in hospital sewage water, which indicates further research needs, especially studies of chronic toxicity.

Protective effects of glycoglycerolipids extracted from spinach on 5-fluorouracil induced intestinal mucosal injury

Glycoglycerolipids are mostly found in plants, however the beneficial effects of the glycoglycerolipids on mammalian body have not been understood. In this study, we investigated the effects of glycolipid extracts from spinach, which highly contained glycoglycerolipids, on mucosal injury induced by 5-fluorouracil (5-FU) in rats. Preadministration of glycolipid extracts from spinach (20 mg/kg body weight) prevented villous atrophy, misaligned crypts, and increased inflammatory cytokines in rat jejunum treated with 5-FU (300 mg/kg body weight) compared with the extracts from soybean. The glycolipid extracts from spinach highly contained monogalactosyl-diacylglycerol (MGDG) and diglactosyl-diacylglycerol (DGDG). In Caco-2 cells, MGDG and DGDG inhibited the production of reactive oxygen species induced by phorbol ester. We concluded that glycolipid extracts from spinach has anti-oxidative and anti-inflammatory effects, and the extract may be useful for prevention of drug-induced mucosal injury and other inflammatory diseases. Tokushima