High doses of taurolidine inhibit advanced intraperitoneal tumor growth in rats

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.

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 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 lock solutions for the prevention of catheter-related bloodstream infections: a systematic review and meta-analysis of randomized controlled trials

Background

Catheter-related bloodstream infections (CRBSIs) are a significant cause of morbidity and mortality in critically ill patients, contributing to prolonged hospital stays and increased costs. Whether taurolidine lock solutions (TLS) are beneficial for the prevention of CRBSIs remains controversial. In this meta-analysis, we aim to assess the efficacy of TLS for preventing CRBSIs.

Methods

We conducted a systematic search of PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials. Eligible studies included randomized controlled trials that reported on the effects of TLS for preventing CRBSIs. The primary outcome in these studies was catheter-related bloodstream infections, with microbial distribution of CRBSI and catheter-associated thrombosis as secondary outcomes. Data were combined using random-effects models owing to significant clinical heterogeneity.

Results

Six randomized controlled trials (RCTs) conducted from 2004 through 2013 involving 431 patients and 86,078 catheter-days were included in the review. TLS were significantly associated with a lower incidence of CRBSIs when compared to heparin lock solutions (Risk Ratio [RR], 0.34; 95% Confidence Interval [CI], 0.21–0.55). Use of TLS significantly decreased the incidence of CRBSIs from gram-negative (G−) bacteria (P = 0.004; RR, 0.27; CI, 0.11–0.65), and was associated with a non-significant decrease in gram-positive (G+) bacterial infections (P = 0.07; RR, 0.41; CI, 0.15–1.09). No significant association was observed with TLS and catheter-associated thrombosis (RR, 1.99; CI, 0.75–5.28).

Conclusions

The use of TLS reduced the incidence of CRBSIs without obvious adverse effects or bacterial resistance. However, the susceptibility of G+ and G- bacteria to taurolidine and the risk for catheter-associated thrombosis of TLS are indeterminate due to limited data. The results should be treated with caution due to the limited sample sizes and methodological deficiencies of included studies. Therefore, additional well-designed and adequately powered RCTs are needed to confirm these findings.

Cytoreductive surgery plus hyperthermic intraperitoneal chemotherapy improves survival of gastric cancer with peritoneal carcinomatosis: evidence from an experimental study

Background

Cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) has been considered as a promising treatment modality for gastric cancer with peritoneal carcinomatosis (PC). However, there have also been many debates regarding the efficacy and safety of this new approach. Results from experimental animal model study could help provide reliable information. This study was to investigate the safety and efficacy of CRS + HIPEC to treat gastric cancer with PC in a rabbit model.

Methods

VX2 tumor cells were injected into the gastric submucosa of 42 male New Zealand rabbits using a laparotomic implantation technique, to construct rabbit model of gastric cancer with PC. The rabbits were randomized into control group (n = 14), CRS alone group (n = 14) and CRS + HIPEC group (n = 14). The control group was observed for natural course of disease progression. Treatments were started on day 9 after tumor cells inoculation, including maximal removal of tumor nodules in CRS alone group, and maximal CRS plus heperthermic intraperitoneal chemoperfusion with docetaxel (10 mg/rabbit) and carboplatin (40 mg/rabbit) at 42.0 ± 0.5°C for 30 min in CRS + HIPEC group. The primary endpoint was overall survival (OS). The secondary endpoints were body weight, biochemistry, major organ functions and serious adverse events (SAE).

Results

Rabbit model of gastric cancer with PC was successfully established in all animals. The clinicopathological features of the model were similar to human gastric PC. The median OS was 24.0 d (95% confidence interval 21.8 - 26.2 d ) in the control group, 25.0 d (95% CI 21.3 - 28.7 d ) in CRS group, and 40.0 d (95% CI 34.6 - 45.4 d ) in CRS + HIPEC group (P = 0.00, log rank test). Compared with CRS only or control group, CRS + HIPEC could extend the OS by at least 15 d (60%). At the baseline, on the day of surgery and on day 8 after surgery, the peripheral blood cells counts, liver and kidney functions, and biochemistry parameters were all comparable. SAE occurred in 0 animal in control group, 2 animals in CRS alone group including 1 animal death due to anesthesia overdose and another death due to postoperative hemorrhage, and 3 animals in CRS + HIPEC group including 1 animal death due to anesthesia overdose, and 2 animal deaths due to diarrhea 23 and 27 d after operation.

Conclusions

In this rabbit model of gastric cancer with PC, CRS alone could not bring benefit while CRS + HIPEC with docetaxel and carboplatin could significantly prolong the survival with acceptable safety.

Oral administration of the anti-proliferative substance taurolidine has no impact on dextran sulfate sodium induced colitis-associated carcinogenesis in mice

Background:

New chemopreventive strategies for ulcerative colitis (UC)-associated dysplasia and cancer have to be evaluated. Taurolidine (TRD) has anti-inflammatory, anti-proliferative and anti-neoplastic properties with almost absent toxicity. The aim of the study was to determine whether TRD decreases dysplasia in the well-characterized Dextran Sulfate Sodium – Azoxymethane (DSS-AOM) animal model for UC-associated carcinogenesis.

Material and Methods:

The DSS-AOM model of carcinogenesis was induced in female inbred C57BL/6 mice. Half of the mice were treated with TRD, the other served as control. After 100 days macroscopic, histological and immunhistochemical (β-Catenin, E-Cadherin, SOX9, Ki-67, Cyclin-D1) examination of the colon was performed.

Results:

Incidence, multiplicity, grading and growth pattern of adenomas did not differ significantly between TRD and control group. In all animals, inflammatory changes were absent. Immunhistochemistry revealed increased expression of Ki-67, β-catenin, SOX9 and Cyclin-D1 in adenomas compared to normal mucosa – without significant difference between TRD and control treatment.

Conclusion:

Oral administration of TRD has no impact on DSS-induced colitis-associated carcinogenesis. However, SOX9 and Cyclin-D1 representing key members of the Wnt pathway have not yet been described in the DSS-AOM model of carcinogenesis – underlining the importance of this oncogenic pathway in this setting.

Establishment and identification of a rabbit model of peritoneal carcinomatosis from gastric cancer

BACKGROUND

Gastric cancer peritoneal carcinomatosis is a common clinical problem, but there are no suitable large animal models to study this problem. This study was to establish a stable rabbit peritoneal carcinomatosis model of gastric cancer using VX2 tumor, and analyze the clinico-pathological features.

METHODS

VX2 tumor was implanted into 36 New Zealand rabbits by 3 methods: laparotomic orthotopic injection of cancer cells into the submucosal layer of the stomach (Group A), laparotomic implantation of tumor tissue into the greater omentum immediately beneath the gastric antrum (Group B), and percutaneous injection of tumor cells directly into the peritoneal cavity (Group C), 12 rabbits in each group. The animals were closely observed and detailed clinico-pathological studies were conducted.

RESULTS

The success rates of peritoneal carcinomatosis formation were 100% (12/12), 91.7% (11/12) and 58.3% (7/12), respectively, for Groups A, B and C (P = 0.019, A versus C; P = 0.077, B versus C; P = 0.500, A versus B, Fisher's exact test). Two weeks after submucosal cancer cells injection in Group A, ulcerative gastric cancer with peritoneal carcinomatosis showed typical VX2 tumor pathology, with widespread intraperitoneal metastatic nodules, bloody ascites and perspicuous pulmonary metastases. The clinico-pathological progression pattern was very similar to patients of advanced gastric cancer with peritoneal carcinomatosis. Groups B and C showed similar pattern of cancer progression, but less aggressive.

CONCLUSIONS

First large animal model of peritoneal carcinomatosis from gastric cancer has been established by laparotomic orthotopic injection of VX2 cancer cells into the submucosal layer of the stomach, providing a more suitable model for surgical interventional studies. The clinico-pathological features of this model resemble human peritoneal carcinomatosis.

Application of a solid tumor model to evaluate tumor recurrence after an open or laparoscopic rectal resection in rats

PURPOSE

We used a solid tumor model to evaluate the influence of laparotomy versus laparoscopy on tumor growth after curative resection for rectal cancer in rats.

METHODS

Colon tumor cells (DHD/K12/TRb) were administered intraperitoneally in 15 rats, which were used as solid tumor donors. Twenty-one days later, a 20-mg piece was then implanted in the rectal submucosa of the study rats (n=45). Animals were randomized into 3 groups for rectal resection either open or laparoscopic using either carbon dioxide (CO2) or helium for pneumoperitoneum. Autopsy took place 21 days after resection and tumor recurrence was evaluated.

RESULTS

Port-site metastasis was observed after laparoscopy with CO2 (1 animal) and helium (1), whereas intraperitoneal tumor growth was detected in 2 and 3 animals of these groups. No tumor recurrence was observed after open surgery.

CONCLUSIONS

Our solid tumor model is a novel neoplastic model that might simulate the clinical situation of an upper rectal carcinoma. It might be helpful to develop new protocols in studying solid tumor biology and different surgical procedures for cancer to address problematic issues in oncologic research.

Antibacterials as anti-inflammatory agents: dual action agents for oral health

BACKGROUND

Inflammatory processes with a range of specialized cells and biochemical mediators form a complex network of inter-related signal transducing pathways that relay information to preserve normal functions. Advances in molecular analyses of the information relay pathways for their constituents and principal ligands along with mechanisms utilized by the host for microbial recognition have stimulated interest in therapeutic agents with dual functionalities i.e. antibacterial and anti-inflammatory effects.

AIM

This review examines clinically tested agents for oral health applications with both antimicrobial and anti-inflammatory effects to include antibiotics, antimicrobials and phenolics.

RESULTS

Bis-phenols such as triclosan, representing a unique dual functional therapeutic for routine oral hygiene, with its demonstrated clinical effects on inhibiting the dental plaque biofilm, reducing inflammation (gingivitis) and subsequent periodontitis is described. Cyclines, comprising another class of approved anti-inflammatory agents used at the patient level for oral health is discussed. Dual active agents in current clinical practice for systemic conditions are highlighted to summarize the clinical validity of dual function agents as an emerging therapeutic strategy.

CONCLUSIONS

Clinical studies demonstrate therapeutic benefits of agents with dual functionality with their effects on microorganisms and the concomitant host inflammatory response. Advances in microbial pathogenesis and resultant inflammation will facilitate progress in this emerging area poised to be a significant milestone for dental therapeutics.

The tumor suppressive reagent taurolidine inhibits growth of malignant melanoma--a mouse model

BACKGROUND

The tumor suppressive agent taurolidine (TRD) inhibits tumor growth of more than 30 cell lines in vitro and reduces tumor load in early and advanced stages of neoplastic disease in animals. TRD has been shown to induce apoptosis of melanoma cells in vitro. Therefore, the effects of TRD on disseminated melanoma were evaluated in a mice model.

METHODS

After general anesthesia, a midline laparotomy was performed and 1.5 million malignant melanoma cells (B78-D14) were applied in the spleen and 1 million cells at the back (C57BL/6). Animals were randomized and either treated intraperitoneally (i.p., n = 40, 7 days, 12 hourly) or intravenously (i.v., n = 40, 2 days, 12 hourly) with 1%, 2%, or 3% TRD or with Ringer's solution (control group). On day 28, all animals were sacrificed and the total tumor weight and the number of metastatic lesions were determined by two investigators blinded for randomization.

RESULTS

The i.p. therapy caused a dose-dependent inhibition of total tumor growth (P = 0.003) and i.p. tumor growth (P = < 0.001), whereas subcutaneous (s.c.) tumor growth was not affected (P = 0.132) compared with the i.p. control group. The i.v. therapy reduced the total tumor growth (P = 0.013) and the s.c. tumor growth (P = 0.016), whereas the i.p. tumor load was not reduced (P = 0.122) compared with the control group. Both i.p. and i.v. therapy with 3% TRD significantly decreased the total number of metastatic lesions. The animal weight was not affected.

CONCLUSIONS

The i.p. and i.v. therapies reduce total tumor weight and number of metastatic lesions of disseminated malignant melanoma in a dose-dependent fashion in mice. Our encouraging findings should be further confirmed in clinical studies examining the influence of TRD in patients with disseminated malignant melanoma for whom prognosis still remains dismal.

Peritoneal instillation of taurolidine or polihexanide modulates intestinal microcirculation in experimental endotoxemia

BACKGROUND AND AIMS

Treatment of peritonitis may include peritoneal lavage/instillation with anti-infective agents like taurolidine or chlorhexidine.

MATERIALS AND METHODS

We examined the effects of peritoneal instillation (INST, 5-ml solution) with taurolidine (TAURO) or polihexanide (POLI-LS) on intestinal microcirculation using intravital microscopy (IVM) in experimental endotoxemia (15 mg/kg lipopolysaccharide i.v.; LPS) in the rat (n = 8 each group), their direct effects on local small blood vessels, aortal rings, and myocardial strips in vitro, as well as plasma interleukin levels.

RESULTS

It was found that LPS produced hypotension (98.8 +/- 9.5 vs 130.4 +/- 10.5 mmHg; mean arterial pressure [MAP], mean +/- standard deviation [SD]), which was further pronounced after INST of TAURO (78.8 +/- 10.8; P < 0.005) or POLI-LS (78.1 +/- 6.0; P < 0.001). IVM revealed a reduction in temporary adhering leucocytes and an increase in firmly adhering leucocytes after INST with TAURO and POLI-LS. Both agents reduced functional capillary density either in the mucosa (POLI-LS vs sham: 259.7 +/- 54 cm/cm(2) vs 337.1 +/- 35.5) or longitudinal muscular layer in LPS rats (TAURO vs sham: 119.8 +/- 14.8 vs 153.7 +/- 11.0). POLI-LS induced local vasodilatation, whereas TAURO induced small vasoconstriction; in vitro, both agents showed vasodilating properties and did not have any effect on myocardial strip contraction.

CONCLUSION

Some of the observed microcirculatory changes could be a result of the direct vascular effects of these agents.