ABSTRACT
The growth characteristic of mouse ascites tumour AISM was observed on two distant passages (35th and 117th) in vivo. The following growth differences were established; the duration of life time of tumour bearing mice is less at the 35th passage (8 days) in comparison to the 117th passage (12 days); the common tumour cell mass at the terminal stage of life of tumour is more than 10 times less at 35th passage (10(8) cells) than at 117th passage (1.2.10(9) cells). The growth rate at 35th passage increases to the 4th day and at 117th passage to the 6th day. It is suggested that the tumour growth rate and the final size of tumor cell mass depend on the cell ploidity and chalone growth control.
Subject(s)
Carcinoma, Ehrlich Tumor/pathology , Animals , Growth Inhibitors , Male , Mice , Mice, Inbred BALB C , Mitotic Index , Time FactorsABSTRACT
The effect of specific cell growth inhibitor (chalone) on the mitotic activity of ascites ISM applied entrapped in liposomes compared to the non-entrapped 'free' form was investigated. The 'free' chalone injected intraperitoneally in BALB/c ascites ISM-bearing mice (1500 mg per kg body weight) decreased the mitotic activity of the tumour by 66 per cent 2.5 h after administration. Five hours after administration, complete restoration of the mitotic index to the control level was observed. Chalone encapsulated into Bangham liposomes (1000 mg per kg body weight) in otherwise identical conditions produced 44 per cent inhibition after 2.5 h, while at 5 h post-injection the mitotic inhibition was still present increasing up to as much as 50 per cent. No such effect was evident by chalone encapsulated in freeze-thawed liposomes (500 mg per kg body weight). The chalone under study specifically inhibits the cell division of the originating tumour cells and has no effect on its DNA synthesis or on the mitosis of the basal layer of the oesophagus and crypts of the intestinal epithelium. The results obtained provide evidence that liposome-entrapped chalone prolongs the inhibition of tumour cell mitosis in comparison to the 'free' one even in a reduced dose. Some possible applications of this approach concerning cancer research and treatment are discussed.
Subject(s)
Antineoplastic Agents/administration & dosage , Growth Inhibitors/administration & dosage , Neoplasms, Experimental/drug therapy , Animals , Carcinoma, Ehrlich Tumor/drug therapy , Liposomes , Male , Mice , Mice, Inbred BALB CABSTRACT
Mitosis inhibitory activity of chalone-containing preparations extracted from cells of Ehrlich's ascites carcinoma (EAC) at varying time of day (9, 13, 17, 21 1, 5 and 9 o'clock) was studied in a temporary suspension culture of EAC. The inhibitory action of the preparations depended on the time of their extraction. This may be indicative of rhythmical alterations of the production or activity of EAC chalone. The maximum activity was demonstrated by the preparations extracted at 5, 9 and 13 o'clock. The activity of the preparations, extracted at 17, 21 and 1 o'clock was considerably less. The degree of mitotic activity inhibition also depends on the dose of duration of action of the chalone-containing preparation.
