Taurolidine inhibits tumor cell growth in vitro and in vivo

Background: Taurolidine, a derivative of the amino acid taurine, exhibits antiendotoxin, anti-bacterial, and antiadherence activity. We hypothesized that Taurolidine may inhibit tumor cell growth, both in an in vitro and in vivo setting. Our aim was to examine the effect of Taurolidine on the growth of a rat metastatic colorectal tumor cell line (DHD/K12/TRb) in vitro and in vivo. Methods: In the in vitro experiments, DHD/K12/TRb cells were incubated with 5, 10, 15, 25, μg/ml of Taurolidine. Cells incubated in culture medium alone were used as controls. Cell proliferation, cell viability, cell death, and cell apoptosis were measured using commercially available techniques. In the in vivo experiment, BD IX rats were randomized into two groups (n = 10/group). Group A (control) underwent laparotomy and instillation of DHD/K12/TRb tumor cells intraperitoneally followed by phosphate buffered saline (PBS). Group B received Taurolidine (100 mg/kg) instead of PBS. Animals were killed after 24 days and tumor burden assessed by counting the number of tumor nodules in the peritoneal cavity. Results: Incubation of the tumor cells with Taurolidine resulted in a 4-fold decrease in proliferation rates (25 ± 4% vs. 100 ± 28% for controls) and a 4-fold increase in cell necrosis as demonstrated by the increase in LDH release (403 ± 28% vs. 100 ± 26% for controls), at a Taurolidine concentration of 25 μg/ml. A dose-dependent decrease in cell viability was also observed. In the in vivo study, local Taurolidine administration resulted in significant decreases in tumor burden (3 ± 1 nodules in Group B animals vs. 649 ± 101 nodules in Group A animals). Conclusions: Taurolidine inhibits the growth of a rat metastatic colorectal tumor cell line in vitro and in vivo and thus may have potential in the prevention of peritoneal metastases.