demecolcine and Carcinoma--Ehrlich-Tumor

Labeling with bromodeoxyuridine and analysis by isopycnic banding for emergence of DNA-helices density-labeled in both strands (HH-DNA) were used to examine whether transient controlled hypoxia induces significant overreplication in the DNA of cultured Ehrlich ascites cells within a single cell cycle. Diverse situations of the hypoxic period (4-8 h) within the BrdUrd labeling time (8-16 h) were tested. If transversal of more than one complete cell cycle by very fast cycling individual cells was avoided by using short BrdUrd labeling periods or by addition of colcemid, HH-DNA was never detected. This indicates that hypoxia does not induce significant overreplication under the conditions chosen and, in particular, that the burst of replicon initiations occurring after reoxygenation of hypoxic cells principally is not due to overreplication.

Topics: Animals; Bromodeoxyuridine; Carcinoma, Ehrlich Tumor; Demecolcine; DNA Replication; Hypoxia; Interphase; Mice

1) The in vitro effect of virus-inhibiting factor (IF) or interferon on Ehrlich ascites tumor and sarcoma 180 was found to be cytostatic, but not cytocidal. 2) Mouse peritoneal macrophages or splenic lymphoid cells, in the presence of IF, did not affect multiplication of the tumor cells examined.

Topics: Animals; Antimetabolites, Antineoplastic; Carcinoma, Ehrlich Tumor; Cell Division; Cell Survival; Cycloheximide; Demecolcine; In Vitro Techniques; Interferons; Lymphocytes; Macrophages; Male; Mice; Sarcoma 180

The author studied the 24-hour changes in the number of normal and colchamine mitoses in the cells of Ehrlich's ascites carcinoma in mice after the injection of colchamine argainst the background of partial synchronization of cell division, obtained as a result of preliminary injection of dibutyryl cyclic 3',5'-AMP, and also in mice after the injection of colchamine alone or dibutyryl cyclic 3',5'-AMP. As shown, synchronization of cell division in the tumour led to the 2,6-fold increase in the number of tumour cells blocked by colchamine and also to the accelerated arrest of colchamine mitoses.

Topics: Animals; Bucladesine; Carcinoma, Ehrlich Tumor; Demecolcine; Drug Therapy, Combination; Male; Mice; Mitosis; Time Factors

Topics: Animals; Carcinoma, Ehrlich Tumor; Cell Line; Cell Nucleus; Demecolcine; Endoplasmic Reticulum; Golgi Apparatus; Lysosomes; Mice; Microtubules; Mitochondria; Phagocytosis; Vacuoles; Vinblastine

Topics: Animals; Ascitic Fluid; Carcinoma, Ehrlich Tumor; Cell Division; Chromosomes; Demecolcine; DNA; Growth Inhibitors; Mice; Mitosis; Neoplasms, Experimental; Plasmacytoma; Sarcoma 180; Thymidine; Time Factors; Tritium