Lewis lung tumor

Several bis(dioxopiperazines) exhibit antitumor activity. Thus, ICRF 159 122 is an inhibitor of DNA synthesis, blocks the cell cycle in G2-M phase and inhibits metastases in the Lewis lung tumor (3LL) animal model without impeding the... 

Li, L., Shin, D. M. and Fidler, I. J. (1990). Ectopic organ environment favors tumorigenicity and production of metastasis by Lewis Lung tumor cells. Invasion Metastasis 10, 129-141. 

Paku, S., Rot, A., Ladanyi, A. and Lapis, K. (1989). Demonstration of the organ preference of liver selected high metastatic Lewis lung tumor cell line. Clin. Exp. Metastasis 7, 599-607. 

PM, K., Kopper, L. and Lapis, K. (1983). Increased metastatic capacity of Lewis lung tumor cells by in vivo selection procedure. Invasion Metastasis 3, 174-182. 

Batkin et al. [105] demonstrated the antimetastatic potential of orally administered bromelain with or without proteolytic and anticoagulant activity on mice. The mice had Lewis lung tumor cells subcutaneously implanted. Although the number of animals used in this study was rather small, the total number of lung metastases was significantly less in animals treated with bromelain than in the control group regardless of the enzymatic activity. 

Mice received 2><10 Lewis lung tumor cells SQ in the right hind flank on day 0. 

It has been observed that when pyran activated macrophages were cultured with Lewis lung tumor cells, the tumor cells DNA content was reduced by 50% but no tumor cell division took place. The decrease in DNA content resulted in tumor cell death as information essential for cell metabolism and/or replication was no longer available to the cell. 

Cell cycle analysis of Lewis lung tumor cells cultured with pyran activated macrophages (Table VI) shows a shift in the cellular population with time from G2M >S->-G. Thus, the population is shifting from states of mitotic activity to less active, senescent states with Increased time of incubation with activated macrophages. If the tumor cells are not dividing it is unlikely that they can do very much harm. Control studies indicate that normal or thioglycollate elicited macrophages to not cause this shift in tumor cell activity. 

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