[Anti-invasive and anti-metastatic effect of lysine oxidase from Trichoderma sp. in vitro and in vivo]

A new fungal strain, Trichoderma sp., discovered in Moscow, produces the antitumor enzyme, lysine-oxidase, which demonstrates an anti-invasive effect in vitro and anti-metastatic activity in vivo. Maximal inhibition of the in vitro invasion of MM1 clone cells was obtained when the tumor cells were pretreated with 2.5 mU/ml of lysine-oxidase; the pretreatment caused a 1.9-times reduction in cell growth and a 1.6-times reduction in the invasive capacity. We studied its anti-metastatic effect on the spreading Lewis lung carcinoma (3LL) in mice from which the primary tumor had been removed. The administration of the enzyme (50 U/kg, i.v.) significantly decreased not only the extent but the number of lung metastases, as compared with the untreated mice. In addition to that, the lysine-oxidase treatment considerably increases the life-span of mice from which the primary tumor had been removed (200 days after 3LL implantation, lysine-oxidase treatment caused surviving of 50% mice in experimental group).