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

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.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).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.Taurolidine (TRD) - a derivate of the aminosulfoacid Taurin - has been clinically used for many years in peritonitis and catheter related blood stream infections due to its anti-microbial and anti-inflammatory properties [1-3]. Recently it has been shown, that TRD also exerts anti-proliferative and anti-neoplastic activity in vitro as well as in vivo [4,5]. TRD has been reported to inhibit proliferation and to induce programmed cell death in a variety of cell lines derived from malignant tumours e.g. glioblastoma [6,7], melanoma [8,9], mesothelioma [10,11], colon carcinoma [12,13], squamous cell oesophageal carcinoma [14] and sarcoma [15,16]. Recently, favourable pharmacokinetic and safety data for TRD have been reported following systemic application in healthy volunteers [17] as wel