Antitumour Activity of Purified Arabinogalactan-peptidoglycan Complex of the Cell Wall Skeleton of Rhodococcus lentifragmentus

Antitumour activity of arabinogalactan-peptidoglycan (AP) complex (peptidoglycan and arabinogalactan liberated by an acid or alkaline treatment from Rhodococcus lentifragmentus AN-115 cell wall skeleton) was examined in mice and compared with that of the cell wall skeleton. The growth of syngeneic fibrosarcoma Meth A cells after implantation in BALB/c mice was significantly suppressed by AP complex, and also regressed after intratumoral injection of AP complex on days 1, 4 and 7 after tumour implantation. Although the activity of peptidoglycan was less than that of AP complex, peptidoglycan also showed both tumour-suppressive and regressive activities. Arabinogalactan did not show antitumour activity. It is interesting that peptidoglycan has an important role in the effect against tumours.