The pharmacokinetics of taurolidine metabolites in healthy volunteers

Taurolidine and Heparin as Catheter Lock Solution for Central Venous Catheters in Hemodialysis

BACKGROUND

Chronic kidney disease can lead to end-stage renal disease, and the prevalence is increasing. Many patients starting hemodialysis require central venous catheters (CVCs). Catheter-related bloodstream infections (CRBSIs) are a common complication and lead to significant morbidity and mortality. Interventions to prevent CRBSI include antimicrobial lock therapy but concern for the development of antimicrobial resistance and adverse effects. Nonantimicrobial antiseptics as catheter lock solutions have also been used. Taurolidine and heparin catheter lock solution is first approved by the Food and Drug Administration for the prevention of CRBSI in patients on hemodialysis. Taurolidine has a unique mechanism of action and favorable safety profile.

MECHANISM OF ACTION, PHARMACODYNAMICS, AND PHARMACOKINETICS

Taurolidine and heparin catheter lock solution have both antimicrobial and anticoagulant properties. Taurolidine is derivative of the amino acid taurine, and heparin is derived from porcine intestinal mucosa. Taurolidine not only damages microbial cell walls but also prevents the adherence of microorganisms to biological surfaces, preventing biofilm formation. Taurolidine and heparin catheter lock solution is intended to be used intraluminally within the catheter and should be aspirated. Because it is used locally, limited pharmacokinetic and pharmacodynamic data are available.

CLINICAL TRIALS

The LOCK-IT-100 trial is a randomized, double-blind, phase 3 study, which included 795 end-stage renal disease patients on hemodialysis with CVC. Taurolidine and heparin was compared with the control heparin alone. The results of the study showed a 71% risk reduction in CRBSI for taurolidine and heparin arm (95% confident interval, 38%-86%, P = 0.0006). Other studies have also shown that taurolidine lock solution leads to decreased CRBSI episodes. Several systematic reviews and meta-analysis consisted of taurolidine in adult, and pediatric populations also showed reduction in the incidence of CRBSIs.

THERAPEUTIC ADVANCE

Taurolidine and heparin lock solution represents a novel preventive strategy for those undergoing hemodialysis through a CVC by reducing the risk of CRBSI. This is significant progress because there are no other similar options available for patients for whom catheters are the only options for their life-saving treatment.

Use of 2% taurolidine lock solution for treatment and prevention of catheter-related bloodstream infections in neonates: a feasibility study

BACKGROUND

Taurolidine lock, a technique used to prevent or treat catheter-related bloodstream infection (CRBSI), is effective in adult and paediatric patients but has been described rarely in neonates. The aim of this descriptive retrospective study, was to determine the feasibility and direct outcomes of prophylactic and therapeutic taurolidine locks in term and preterm neonates.

METHODS

We implemented the use of therapeutic taurolidine lock in addition to antibiotic treatment with the aim of catheter salvage in critical neonates with difficult vascular access (group 1). In addition, we introduced taurolidine lock as a preventive measure in neonates with a central venous catheter (CVC) at high risk of developing CRBSI (group 2). Every 24 h (in the treatment group) a 2% taurolidine solution was injected and the catheter locked for at least 120 min, until infection clearance (group 1). In the preventive group, the catheter was locked for 30 min every 48 h until CVC removal (group 2).

FINDINGS

Thirty-seven neonates who received taurolidine were included in this study. We did not observe any major adverse events. In group 1 (21 cases), clinical symptom disappearance and bacteraemia clearance were achieved without catheter removal in 18 cases (85.7%); in the other three neonates the catheter was removed shortly after the start of the locks as it was possible to replace the CVC. In group 2 (16 neonates), no CRBSI was observed during the duration of the catheter placement.

CONCLUSIONS

In this retrospective study, taurolidine was successfully used in neonates both for prevention and treatment of CRBSI, without major undesired effects. A larger cohort and a randomized clinical trial is warranted in order to establish its efficacy and safety in neonates.

In vitro comparison of the effectiveness of various antimicrobial locks with taurolidine in the treatment and prevention of catheter-related bloodstream infections in patients receiving parenteral nutrition

OBJECTIVES

To evaluate the effectiveness of various taurolidine solutions in the prevention and treatment of catheter-related bloodstream infections (CRBSIs) caused by the entire spectrum of microbes in patients receiving parenteral nutrition in a shorter period of time.

METHODS

The in vitro method was used to test for eradication of biofilm. Different locks were used: TauroSept (2%), TauroLock (1.35%), TauroLock half concentration, and 3.5% taurolidine and tested on Staphylococcus (S.) epidermidis, S. aureus, S. hominis, methicillin-resistant S. aureus (MRSA), Pseudomonas (P.) aeruginosa (PSAE), multidrug-resistant P. aeruginosa (MR PSAE), vancomycin-resistant enterococci, Klebsiella pneumoniae producing carbapenemase (KPC), Klebsiella pneumoniae producing extended-spectrum beta-lactamase (KLPN ESBL), Candida (C.) albicans, and C. glabrata. Broviac catheters were incubated for growth of each organism and then incubated in lock solutions. Colony forming units (CFUs) were then counted after 30 min, 60 min, and 120 min of incubation.

RESULTS

A statistically significant decrease in CFUs was observed after 30 min of taurolidine exposure for S. hominis, PSAE, KLPN ESBL, KLPN KPC, C. albicans, and C. glabrata; after 60 min of exposure for S. epidermidis, PSAE, MR PSAE, KLPN ESBL, KPC, C. albicans, and C. glabrata; and after 120 min of exposure for S. epidermidis, S. hominis, S. aureus, PSAE, MR PSAE, KLPN ESBL, KPC, C. albicans, C. glabrata.

CONCLUSIONS

The application of taurolidine is effective in the treatment of CRBSIs. Taurolidine proved to be more effective against Gram-negative microorganisms during a 30-min exposure. Using 0.675% taurolidine is still effective. To achieve the required antimicrobial effect, the catheter must be sanitized for at least 2 h.

Salvage of Cardiac Implantable Electronic Device Pocket Infection with Skin Erosion in Frail 92-Year-Old

We reported the novel use of a taurolidine-containing antimicrobial solution in the successful salvage of a partially exposed and polymicrobially infected cardiac implantable electronic device pulse generator in a frail patient unfit for lead extraction. The old, salvaged device was entirely internalized, and there were no signs of recurrent infection at 9 months follow-up.

Salvage of infected cardiac implantable electronic device with taurolidine—a case report

Background

Cardiac implantable electronic devices (CIEDs) are commonly used to treat cardiac arrhythmias and prevent sudden cardiac death. Complications of CIED therapy include component malfunction, lead dislodgement, skin erosion and infection. Infection can result in significant morbidity and even mortality. The recommended treatment of CIED skin erosion and infection is urgent complete device extraction. When this is infeasible due to patient or resource factors, an attempt could be made to salvage the exposed or infected CIED system by debridement of all the infected necrotic tissues and irrigation of the pocket and contaminated hardware with anti-septic/antibiotic solutions. Taurolidine, when dissolved in an aqueous solution, produces a broad spectrum of antimicrobial actions and may be used as a novel irrigation agent during CIED salvage.

Case presentation

This report describes the first use of a taurolidine-containing solution for pocket irrigation and in situ hardware sterilisation that resulted in the successful salvage of a CIED infected with multi-resistant Staphylococcus epidermidis.

Conclusions

A taurolidine-containing antimicrobial solution can be a safe and effective alternative to traditional antiseptic/antibiotic solutions for pocket irrigation and in situ hardware sterilisation during CIED salvage, and may produce better clinical outcomes by some unique mechanisms of action such as inhibition of biofilm formation and neutralisation of endotoxins, with little risk of inducing and encountering resistance.

A 2% taurolidine catheter lock solution prevents catheter-related bloodstream infection (CRBSI) and catheter dysfunction in hemodialysis patients

HIGHLIGHTS

2% taurolidine catheter lock solution without additives is safe and efficient. CRBSI and dysfunction rates compare favorably against other studies in hemodialysis.

BACKGROUND

In hemodialysis patients, catheter-related bloodstream infection (CRBSI) and catheter dysfunction are common and cause significant morbidity, mortality, and costs. Catheter lock solutions reduce CRBSI and catheter dysfunction rates, but solutions containing heparin, citrate, or antibiotics are associated with adverse effects. Due to its antimicrobial and antithrombotic properties and benign safety profile, taurolidine is suitable for use in catheter lock solutions. In this study the effectiveness and safety of a catheter lock solution containing 2% taurolidine without citrate or heparin (TauroSept®, Geistlich Pharma AG, Wolhusen, Switzerland) in hemodialysis patients were investigated for the first time.

METHODS

Data from 21 patients receiving chronic hemodialysis via tunneled central venous catheters with 2% taurolidine solution as a catheter lock were analyzed in a single-center retrospective study and compared with the existing literature in a review. The primary endpoint was CRBSI rate. Secondary endpoints included catheter dysfunction, treatment, and costs; catheter technical problems, resolution, and costs; and adverse events. Data were compared to outcomes with standard lock solutions in the literature.

RESULTS

No CRBSIs occurred during the observation period of 5,639 catheter days. The catheter dysfunction rate was 0.71 per 1,000 catheter days, and the catheter dysfunction treatment costs were CHF (Swiss Franc) 543 per patient. No technical problems or adverse events related to the use of 2% taurolidine-containing catheter lock solution were observed. These results compare favorably with other catheter lock solutions.

CONCLUSIONS

A solution containing 2% taurolidine seems suitable as a hemodialysis catheter lock. In a Swiss cohort, it prevented CRBSI, limited catheter dysfunction, and was cost-efficient.

Does taurolidine have any effect on liver regeneration and oxidation in the experimental hepatectomy model?

Objective: Taurolidine is a bicyclic molecule produced by the natural amino acid taurine. Antibacterial, antiendotoxic and cytoprotective effects of taurolidine have been shown experimentally. Data on the effects of taurolidine on oxidative stress and hepatic regeneration are limited. The aim of the study was to evaluate the effect of taurolidine on hepatic regeneration and oxidative stress in rats undergoing partial hepatectomy.

Material and Methods: Forty adult, male Wistar Albino rats were randomly divided into four equal groups: sham (S) group (n= 10), post-sham opera- tion taurolidine administered (ST) group (n= 10), partial hepatectomy (H) group (n= 10) and post-partial hepatectomy taurolidine administered (HT) group (n= 10). 100 mg/kg/day taurolidine was administered for seven days. Blood and liver tissue samples were collected on postoperative day seven. Liver tissue malondialdehyde, glutathione and Cu-Zn superoxide dismutase activity (SOD) were measured to assess oxidative stress. Binuclear hepato- cyte and Ki-67 antigen levels were measured to evaluate hepatic regeneration.

Results: There was no difference between the groups for malondialdehyde, Cu-Zn superoxide dismutase and glutathione levels (p> 0.05). Binuclear nuclei levels were comparable between the H and HT groups (p= 0.06), while taurolidine decreased binuclear hepatocyte levels in the sham operated groups (p= 0.02). Taurolidine application decreased Ki-67 levels after partial hepatectomy (p= 0.001).

Conclusion: Taurolidine may cause anti-regenerative effects after partial hepatectomy without causing oxidative damage.

Dual functionality of the antimicrobial agent taurolidine which demonstrates effective anti-tumor properties in pediatric neuroblastoma

High-risk, relapsed and refractory neuroblastoma are associated with poor 5-years survival rates, demonstrating the need for investigational therapeutic agents to treat this disease. Taurolidine is derived from the aminosulfoacid taurine and has known anti-microbial and anti-inflammatory properties. Taurolidine has also demonstrated anti-neoplastic effects in a range of cancers, providing the rationale to investigate the activity of taurolidine against neuroblastoma in preclinical studies. We investigated the in vitro activity of taurolidine against neuroblastoma using the alamar blue cytotoxicity assay, phase-contrast light microscopy, western blotting and analysis of global gene expression by RNA-Seq. In vivo activity of taurolidine was evaluated using mouse xenograft models. In vitro pre-clinical data show that taurolidine is cytotoxic to neuroblastoma cell lines, inducing cell death by apoptosis. Analysis of global gene expression and determination of signaling pathway activation scores using the in silico Pathway Activation Network Decomposition Analysis (iPANDA) platform indicates that taurolidine has an effect on the Notch, mitogen-activated protein kinase (MAPK) and interleukin-10 (IL-10) signaling pathways. In vivo experiments in xenograft mouse models show that taurolidine decreases tumor growth and improves survival. These results provide supportive pre-clinical data on the activity of taurolidine against neuroblastoma. The findings support the rationale for further evaluation of taurolidine for the treatment of relapsed/refractory neuroblastoma patients in an early phase clinical trial.

Innovative substance 2250 as a highly promising anti-neoplastic agent in malignant pancreatic carcinoma - in vitro and in vivo

BACKGROUND

Former studies already revealed the anti-neoplastic properties of the anti-infective agent Taurolidine (TRD) against many tumor species in vitro and in vivo. Its anti-proliferative and cell death inducing capacity is largely due to its main derivative Taurultam (TRLT). In this study it could be demonstrated, that substance 2250 - a newly defined innovative structural analogue of TRLT - exhibits an anti-neoplastic effect on malignant pancreatic carcinoma in vitro and in vivo.

METHODS

The anti-neoplastic potential of substance 2250 as well as its mode of action was demonstrated in extensive in vitro analysis, followed by successful and effective in vivo testings, using xenograft models derived from established pancreatic cancer cell lines as well as patient derived tissue.

RESULTS

Our functional analysis regarding the role of oxidative stress (ROS) and caspase activated apoptosis showed, that ROS driven programmed cell death (PCD) is the major mechanisms induced by substance 2250 in pancreatic carcinoma. What is strongly relevant towards clinical practice is especially the observed inhibition of patient derived pancreatic cancer tumor growth in mice treated with this new substance in combination with its sharply higher metabolic stability.

CONCLUSION

These encouraging results provide new therapeutical opportunities in pancreatic cancer treatment and build the basis for further functional analysis as well as first clinical studies for this promising agent.

Taurolidine and congeners activate hTRPA1 but not hTRPV1 channels and stimulate CGRP release from mouse tracheal sensory nerves

Taurolidine has long been in clinical use as an antimicrobial irrigation that does not impede wound healing. It can even be administered intravenously (30 g/day) to treat sepsis or to exert newly recognized antineoplastic actions. Only one irritant effect is reported, that is, to temporarily induce burning pain of unknown origin when applied to body cavities or peripheral veins. The structure of the molecule suggested the chemoreceptor channel TRPA1 as a potential target, which was verified measuring stimulated CGRP release from sensory nerves of the isolated mouse trachea and calcium influx in hTRPA1‐transfected HEK293 cells. With both methods, the concentration–response relationship of taurolidine exceeded the threshold value below 500 μmol/L and 100 μmol/L, respectively, and reached saturation at 1 mmol/L. The clinical 2% taurolidine solution did not evoke greater or longer lasting responses. The reversible tracheal response was abolished in TRPA1^−/− but retained in TRPV1^−/− mice. Consistently, hTRPV1‐HEK showed no calcium influx as a response, likewise native HEK293 cells and hTRPA1‐HEK deprived of extracellular calcium did not respond to taurolidine 1 mmol/L. The metabolite taurultam and its oxathiazine derivative, expected to cause less burning pain, showed weak tracheal irritancy only at 10 mmol/L, acting also through hTRPA1 but not hTRPV1. In conclusion, taurolidine, its metabolite, and a novel derivative showed no unspecific cellular effects but selectively, concentration‐dependently and reversibly activated the irritant receptor TRPA1 in CGRP‐expressing, thus nociceptive, neurons. The clinical solution of 2% taurolidine (~70 mmol/L) can, thus, rightly be expected to cause transient burning pain and neurogenic inflammation.

Taurolidine cooperates with antineoplastic drugs in neuroblastoma cells

Neuroblastoma is the most common extracranial tumor in childhood. Outcome of stage 4 disease remains poor and the development of novel therapeutic approaches is thus urgently needed. Taurolidine (TRD), originally invented to avoid catheter infections, has shown to exhibit antineoplastic activity in various cancers. The growth of neuroblastoma cell lines is inhibited by TRD as recently demonstrated. Further analysis disclosed a significant negative growth effect of TRD on the four neuroblastoma cell lines SH-EP TET21N, SK-N-AS, SK-N-BE(2)-M17 and SK-N-SH. Detected IC50 (51-274 μM; 48 h) are promising and correspond to clinically-achievable plasma levels. Apoptosis was induced (76-86%; 48 h) in a time-dependent manner mediated by a simultaneous activation of the intrinsic and extrinsic pathways. This was confirmed by cleavage of caspases -3, -8 and -9 and abrogation of apoptosis by pan-caspase inhibition. Application of TRD resulted in a significant enhancement of cytotoxic drugs vincristine/doxorubicin (2/3 of 4 cell lines) making TRD a promising candidate to be included in neuroblastoma therapy regimens in the future.

Taurolidine induces epithelial-mesenchymal transition via up-regulation of the transcription factor Snail in human pancreatic cancer cell lines

PURPOSE

The taurine derivative taurolidine (TRD) exerts anti-neoplastic effects in a variety of tumor models. On the other hand, TRD at low doses was shown to reduce cell-cell adhesion, a prerequisite for metastasis. The aim of this study was to elucidate the effects of low-dose TRD on pancreatic cancer.

METHODS

Human pancreatic cancer cell lines representing diverse states of differentiation were exposed to TRD for 24 h. Cell viability was assessed by MTT assay and trypan blue staining, apoptosis by caspase-3/7 activity, and flow-cytometric cell cycle analysis. Expression of Snail and E-cadherin was analyzed by polymerase chain reaction and Western blotting.

RESULTS

MTT-tested viability of all pancreatic cancer cell lines decreased dose-dependently up to 50 % of the untreated control. In contrast to staurosporine TRD (100 and 250 μM) did not induce apoptosis but increased the percentage of cells in G1/G0 arrest. Correlation of MTT test and trypan blue staining revealed a decreased adherence of vital tumor cells at 250 μM TRD. This was associated with reduced expression of the adhesion molecule E-cadherin and an increased expression of the transcription factor Snail, a regulator of epithelial-mesenchymal transition (EMT).

CONCLUSION

Low-dose TRD reduces not only viability but also cell-cell adherence and E-cadherin expression of pancreatic cancer cells, whereas the expression of the EMT inducer Snail was increased. By induction of these EMT hallmarks, low-dose TRD may promote metastasis in pancreatic cancer.

Redox-directed cancer therapeutics: Taurolidine and Piperlongumine as broadly effective antineoplastic agents (review)

Targeting the oxygen stress response pathway is considered a promising strategy to exert antineoplastic activity in a broad spectrum of tumor types. Supporting this view, we summarize the mechanism of action of Taurolidine and Piperlongumine, two antineoplastic agents with strikingly broad tumor selectivity. Taurolidine enhances the oxidative stress (ROS) selectively in tumor cells. Its cytotoxicity for various tumor cells in vitro and in vivo, which includes tumor stem cells, is based on the induction of programmed cell death, largely via apoptosis but also necroptosis and autophagy. The redox-directed mechanism of action of Taurolidine is apparent from the finding that reducing agents e.g., N-acetylcysteine or glutathione impair its cytotoxicity, while its effectiveness is enhanced by agents which inhibit the cellular anti‑oxidant capacity. A similar redox-directed antineoplastic action is shown by Piperlongumine, a recently described experimental drug of plant origin. Taurolidine is particularly advantageous in surgical oncology as this taurine-derivative can be applied perioperatively or systemically with good tolerability as shown in initial clinical applications.

Pharmacokinetic study and evaluation of the safety of taurolidine for dogs with osteosarcoma

Background

Osteosarcoma in dogs and humans share many similarities and the dog has been described as an excellent model to study this disease. The median survival in dogs has not improved in the last 25 years. Taurolidine has been shown to be cytotoxic to canine and human osteosarcoma in vitro. The goals of this study were to determine the pharmacokinetics and safety of taurolidine in healthy dogs and the safety of taurolidine in combination with doxorubicin or carboplatin in dogs with osteosarcoma.

Methods

Two percent taurolidine was infused into six healthy dogs (150 mg/kg) over a period of two hours and blood samples were taken periodically. One dog received taurolidine with polyvinylpyrrolidone (PVP) as its carrier and later received PVP-free taurolidine as did all other dogs in this study. Serum taurolidine concentrations were determined using high-performance liquid chromatography (HPLC) online coupled to ESI-MS/MS in the multiple reaction monitoring mode. Subsequently, the same dose of taurolidine was infused to seven dogs with osteosarcoma also treated with doxorubicin or carboplatin.

Results

Taurolidine infusion was safe in 6 healthy dogs and there were no significant side effects. Maximum taurolidine serum concentrations ranged between 229 to 646 μM. The dog that received taurolidine with PVP had an immediate allergic reaction but recovered fully after the infusion was stopped. Three additional dogs with osteosarcoma received doxorubicin and taurolidine without PVP. Toxicities included dilated cardiomyopathy, protein-losing nephropathy, renal insufficiency and vasculopathy at the injection site. One dog was switched to carboplatin instead of doxorubicin and an additional 4 dogs with osteosarcoma received taurolidine-carboplatin combination. One incidence of ototoxicity occurred with the taurolidine- carboplatin combination. Bone marrow and gastro-intestinal toxicity did not appear increased with taurolidine over doxorubicin or carboplatin alone.

Conclusions

Taurolidine did not substantially exacerbate bone marrow or gastro-intestinal toxicity however, it is possible that taurolidine increased other toxicities of doxorubicin and carboplatin. Administering taurolidine in combination with 30 mg/m² doxorubicin in dogs is not recommended but taurolidine in combination with carboplatin (300 mg/m²) appears safe.

Central venous catheters and catheter locks in children with cancer: a prospective randomized trial of taurolidine versus heparin

BACKGROUND

To determine if the catheter lock taurolidine can reduce the number of catheter-related bloodstream infections (CRBSI) in pediatric cancer patients with tunneled central venous catheters (CVC).

PROCEDURE

During a study period of 34 months, 129 newly placed tunneled CVCs in 112 patients were randomly assigned to standard lock with heparin solution or experimental lock with a taurolidine solution (ClinicalTrials.gov Identifier NCT00735813).

RESULTS

Sixty-five CVCs were included in the standard group and 64 CVCs in the experimental group. The groups were comparable regarding patients' characteristics. A total number of 72 bloodstream infections of which 33 were CRBSIs were observed during 39,127 CVC-days. A lower rate of CRBSI (0.4 per 1,000 CVC-days) was observed in the experimental arm compared with the standard arm (1.4 per 1,000 CVC-days, incidence rate ratio (IRR) = 0.26; 95% confidence interval (CI) 0.09-0.61; P = 0.001). A lower rate of total bloodstream infections (1.2 per 1,000 CVC-days) was also observed in the experimental arm compared with the standard arm (2.5 per 1,000 CVC-days, IRR = 0.49; 95% CI 0.29-0.82; P = 0.004). Median interval from catheter insertion until first CRBSI was significantly lower in the standard group (156 days, range 12-602) compared with the experimental group (300 days, range 12-1,176; P = 0.02). Premature removal of the CVC due to infection and overall CVC survival were similar in the two study groups.

CONCLUSION

Locking of long-term tunneled CVC with taurolidine significantly reduces catheter-related bloodstream infections in children with cancer.

The effects of taurolidine alone and in combination with doxorubicin or carboplatin in canine osteosarcoma in vitro

Background

Osteosarcoma (OS) affects over 8000 dogs/year in the United States. The disease usually arises in the appendicular skeleton and metastasizes to the lung. Dogs with localized appendicular disease benefit from limb amputation and chemotherapy but most die within 6–12 months despite these treatments. Taurolidine, a derivative of taurine, has anti-tumor and anti-angiogenic effects against a variety of cancers. The following in vitro studies tested taurolidine as a candidate for adjuvant therapy for canine OS. Tests for p53 protein status and caspase activity were used to elucidate mechanisms of taurolidine-induced cell death.

Results

Taurolidine was cytotoxic to osteosarcoma cells and increased the toxicity of doxorubicin and carboplatin in vitro. Apoptosis was greatly induced in cells exposed to 125 μM taurolidine and less so in cells exposed to 250 μM taurolidine. Taurolidine cytotoxicity appeared caspase-dependent in one cell line; with apparent mutant p53 protein. This cell line was the most sensitive to single agent taurolidine treatment and had a taurolidine-dependent reduction in accumulated p53 protein suggesting taurolidine’s effects may depend on the functional status of p53 in canine OS.

Conclusion

Taurolidine’s cytotoxic effect appears dependent on cell specific factors which may be explained, in part, by the functional status of p53. Taurolidine initiates apoptosis in canine OS cells and this occurs to a greater extent at lower concentrations. Mechanisms of cell death induced by higher concentrations were not elucidated here. Taurolidine combined with doxorubicin or carboplatin can increase the toxicity of these chemotherapy drugs and warrants further investigation in dogs with osteosarcoma.

Gene expression analysis of cell death induction by taurolidine in different malignant cell lines

Background

The anti-infective agent Taurolidine (TRD) has been shown to have cell death inducing properties, but the mechanism of its action is largely unknown. The aim of this study was to identify potential common target genes modulated at the transcriptional level following TRD treatment in tumour cell lines originating from different cancer types.

Methods

Five different malignant cell lines (HT29, Chang Liver, HT1080, AsPC-1 and BxPC-3) were incubated with TRD (100 μM, 250 μM and 1000 μM). Proliferation after 8 h and cell viability after 24 h were analyzed by BrdU assay and FACS analysis, respectively. Gene expression analyses were carried out using the Agilent -microarray platform to indentify genes which displayed conjoint regulation following the addition of TRD in all cell lines. Candidate genes were subjected to Ingenuity Pathways Analysis and selected genes were validated by qRT-PCR and Western Blot.

Results

TRD 250 μM caused a significant inhibition of proliferation as well as apoptotic cell death in all cell lines. Among cell death associated genes with the strongest regulation in gene expression, we identified pro-apoptotic transcription factors (EGR1, ATF3) as well as genes involved in the ER stress response (PPP1R15A), in ubiquitination (TRAF6) and mitochondrial apoptotic pathways (PMAIP1).

Conclusions

This is the first conjoint analysis of potential target genes of TRD which was performed simultaneously in different malignant cell lines. The results indicate that TRD might be involved in different signal transduction pathways leading to apoptosis.

Comparative analysis of cell death induction by Taurolidine in different malignant human cancer cell lines

Background

Taurolidine (TRD) represents an anti-infective substance with anti-neoplastic activity in many malignant cell lines. So far, the knowledge about the cell death inducing mechanisms and pathways activated by TRD is limited. The aim of this study was therefore, to perform a comparative analysis of cell death induction by TRD simultaneously in different malignant cell lines.

Materials and methods

Five different malignant cell lines (HT29/Colon, Chang Liver/Liver, HT1080/fibrosarcoma, AsPC-1/pancreas and BxPC-3/pancreas) were incubated with increasing concentrations of TRD (100 μM, 250 μM and 1000 μM) for 6 h and 24 h. Cell viability, apoptosis and necrosis were analyzed by FACS analysis (Propidiumiodide/AnnexinV staining). Additionally, cells were co-incubated with the caspase Inhibitor z-VAD, the radical scavenger N-Acetylcystein (NAC) and the Gluthation depleting agent BSO to examine the contribution of caspase activation and reactive oxygen species in TRD induced cell death.

Results

All cell lines were susceptible to TRD induced cell death without resistance toward this anti-neoplastic agent. However, the dose response effects were varying largely between different cell lines. The effect of NAC and BSO co-treatment were highly different among cell lines - suggesting a cell line specific involvement of ROS in TRD induced cell death. Furthermore, impact of z-VAD mediated inhibition of caspases was differing strongly among the cell lines.

Conclusion

This is the first study providing a simultaneous evaluation of the anti-neoplastic action of TRD across several malignant cell lines. The involvement of ROS and caspase activation was highly variable among the five cell lines, although all were susceptible to TRD induced cell death. Our results indicate, that TRD is likely to provide multifaceted cell death mechanisms leading to a cell line specific diversity.

The evolving role of taurolidine in cancer therapy

BACKGROUND AND DESIGN

Taurolidine consists of two taurinamide rings derived from the naturally occurring amino acid taurine. It has been utilized to prevent adhesions, as an antimicrobial, and as an anti-inflammatory agent. More recently, it has been found to exert antineoplastic activity. We reviewed the literature regarding taurolidine and its role in cancer treatment.

RESULTS AND CONCLUSION

Taurolidine induces cancer cell death through a variety of mechanisms. Even now, all the antineoplastic pathways it employs are not completely elucidated. It has been shown to enhance apoptosis, inhibit angiogenesis, reduce tumor adherence, downregulate proinflammatory cytokine release, and stimulate anticancer immune regulation following surgical trauma. Apoptosis is activated through both a mitochondrial cytochrome-c-dependent mechanism and an extrinsic direct pathway. A lot of in vitro and animal data support taurolidine's tumoricidal action. Taurolidine has been used as an antimicrobial agent in the clinical setting since the 1970s and thus far appears nontoxic. The nontoxic nature of taurolidine makes it a favorable option compared with current chemotherapeutic regimens. Few published clinical studies exist evaluating the role of taurolidine as a chemotherapeutic agent. The literature lacks a gold-standard level 1 randomized clinical trial to evaluate taurolidine's potential antineoplastic benefits. However, these trials are currently underway. Such randomized control studies are vital to clarify the role of taurolidine in modern cancer treatment.