Inhibition of systemic TNF-alpha cytotoxicity in cancer patients by D-peptidoglycan.

The current study was designed to investigate direct inhibitory effects of N-acetyl-glucosaminyl-muramyldipeptide (GMDP) over the cytotoxic nature of TNF-alpha. A lactate dehydrogenase (LDH) assay of the inhibition of TNF-alpha cytotoxicity was done in vitro on the following cell lines: A549 (human lung carcinoma cells), A431 (human breast cancer cells) and L929 (mouse breast cancer cells). In a double-blind placebo-controlled trial, cancer patients with an elevated activity of all five LDH isoensymes were randomized to receive either a GMDP solution or a placebo; 63 patients were evaluated every third day for the mean daily number of episodes of nausea or vomiting, changes in clinical status, cell blood count and blood chemistry.