Inhibitory effect of polycations on the transplantability of mouse leukaemia reversed by heparin

Evidence for effects of heparin on cell surfaces influencing experimental metastases

“…As polyanions like heparin do not seem to penetrate intracellularly (Sherman, 1964;Larsen and Thorling, 1969), the action probably takes place on the cell surfaces. In the present study, evidence for an alteration of the cell surfaces was found in vitro as changes in cellular volumes.…”

Chalone-like effect abrogated by dextran sulphate and heparin polyanion pretreatment of target cells

“…If chalones are of importance to normal cell growth regulation, an inhibited interaction of chalone with the surface of malignant cells may be essential for the tumour growth. Polycation treatment of transplanted tumour cells (Richardson et al, 1959;Larsen and Olsen, 1968;Moroson, 1971), and spontaneous and virus induced mouse leukaemia (Ebbesen, 1974) has an inhibitory influence on tuimour progression, while polyanion may enhance tumour progressioni.…”

Incidence of Nasopharyngeal Carcinoma in Malaysia, with Special Reference to the State of Selangor

“…Therefore the prolonged survival of polyeation treated AKR mice must be an effect unrelated to an influence of polycation on spread of the endogeneous leukaemia virus (Rowe and Pincus, 1972) in these mice. A direct inhibitory influence of high concentrations of polycation on cell metabolism (Larsen and Olsen, 1968), cell division (Moroson, 1971) and cell movement (Ebbesen and Guttler, unpublished) has been observed in vitro. Judgement of the relevance of these observations for in vivo conditions awaits further studies.…”

“…Noninfected BALB/c mice treated weekly with the polycations, DEAE-d and polybrene, and those given our diluent (MEM), were alive after 12 months of treatment. In It has previously been shown that in vivo growth of transplanted leukaemic cells may be inhibited both by polycation treatment of the cells to be grafted (Larsen and Olsen, 1968) and by polycation treatment of the recipient animal (Moroson, 1971). The present work demonstrates an inhibitory effect of polycations on both spontaneous and virus induced leukaemia.…”

“…In vitro incubation of cells with polycations or polyanions will alter their net charge (Weiss, 1967) and alter the transplantability of leukaemia cells (Larsen and Olsen, 1968). Malignant cells are often more negatively charged than normal cells (Ambrose, James and Lowick, 1956).…”