The standardized mistletoe preparation Lektinol has antitumoral potencies
© BioMed Central Ltd 2001
Received: 10 May 2001
Published: 31 May 2001
Extracts of Viscum albumL have been used for decades for non-specific stimulation of the immune system in cancer therapy. Mistletoe lectins have been identified as the active components, with cytotoxic and immunomodulatory activities. New experimental data demonstrate that the special extract preparation Lektinol® (Madaus AG, Cologne, Germany), standardized for bioactive mistletoe lectin (ML), has antitumoral potencies in vitro and in animal tumor models.
In vitro studies on human tumor cell lines and xenografts showed Lektinol to be highly cytotoxic (ie toward breast, lung, prostate and renal cell cancers).
The in vivo antitumoral effects of Lektinol were examined in different subcutaneously growing murine neoplasms following repeated intraperitoneal treatment of 0.3-3-30-300 ng ML/kg. Marked tumor growth inhibition was observed with Renca renal carcinoma, C8 colon 38, and F9 testicular teratoma. The antimetastatic effects of Lektinol were investigated in the B16 melanoma model in mice. Following a single intravenous injection of the melanoma cells, the daily treatment with 3-30-150 ng ML/kg significantly reduced the formation of lung metastases. In parallel, Lektinol enhanced several immune parameters (ie the number of MAC-1+ mononuclear cells and CD4+8+ thymocytes in the tumor-bearing animals). In a further study, the effects of locally administered Lektinol were evaluated in the MB49 urinary bladder carcinoma model in mice. After a single instillation of the tumor cells, Lektinol was given repeatedly by intravesical administration of 3-30 ng ML/0.1 ml/animal. Lektinol showed a distinct effect on survival ratio, growth of primary bladder tumors and the formation of multiple metastases.