Further characterization of the in vitro assay for inhibitors of metabolic cooperation in the Chinese hamster V79 cell line
- 1 January 1985
- journal article
- research article
- Published by Oxford University Press (OUP) in Carcinogenesis: Integrative Cancer Research
- Vol. 6 (3), 361-366
- https://doi.org/10.1093/carcin/6.3.361
Abstract
12-O-Tetradecanoylphorbol-13-acetate (TPA) has been previously shown to inhibit metabolic cooperation in Chinese hamster V79 cells. An in vitro assay, based on this phenomenon, has been developed to study tumor promoters. Several parameters concerning the metabolic cooperation assay using V79 Chinese hamster cells were further investigated in this report. Pretreatment of the cells with TPA in situ for different periods of time did not result in any detectable change in the inhibition of metabolic cooperation. If cells were replated after TPA treatment, a different result was obtained. There was an apparent decrease in the ability of TPA to inhibit metabolic cooperation when TPA was added back to the TPA-pretreated cultures. However, when TPA was omitted from the TPA pretreated cultures after replating, the inhibition of metabolic cooperation remained high. It was also found that pretreatment of the cells with another chemical, aldrin, exhibited the same pattern as the in situ TPA pretreatment effect on inhibition of metabolic cooperation. In order to obtain a high level of inhibition of metabolic cooperation when using aldrin in this assay, it was determined that the chemical needed to be present for more than one day. Our studies also showed that a 24 h treatment with 6-thioguanine did not kill 6-thioguanine-sensitive cells quickly, nor did it prevent them from performing metabolic cooperation. The relationship of cell density and TPA concentration was also studied. It was observed that a higher cell density required higher TPA concentration to inhibit, maximally, metabolic cooperation. A ‘down regulation’ type effect was noted when culture was challenged with different concentrations of TPA. These results were interpreted to be consistent with the hypothesis that inhibited gap-junctional intercellular communication is one of the components of tumor promotion.This publication has 25 references indexed in Scilit:
- INHIBITION OF THE FORMATION OF ELECTRICAL CELL COUPLING OF FL CELLS BY TUMOR PROMOTERS1981
- Specific high affinity cell membrane receptors for biologically active phorbol and ingenol estersNature, 1980
- Studies on the mechanism by which a tumor promoter inhibits binding of epidermal growth factor to cellular receptorsCarcinogenesis: Integrative Cancer Research, 1980
- Structure of the junction between communicating cellsNature, 1980
- EFFECT OF 12-O-TETRADECANOYLPHORBOL-13-ACETATE ON THE MORPHOLOGY AND GROWTH OF C3H-10T1/2 MOUSE EMBRYO CELLS1980
- Specific binding of phorbol ester tumor promotersProceedings of the National Academy of Sciences, 1980
- Tumor promoters inhibit metabolic cooperation in cocultures of epidermal and 3T3 cellsBiochemical and Biophysical Research Communications, 1979
- Junctional intercellular communication and the control of growthBiochimica et Biophysica Acta (BBA) - Reviews on Cancer, 1979
- EFFECT OF PHORBOL ESTER TUMOR PROMOTERS ON THE EXPRESSION OF MELANOGENESIS IN B-16 MELANOMA-CELLS1979
- The mechanism of action and interaction of regulators of cell replicationBiosystems, 1978