Effects of beta-mercaptoethanol-containing medium and feeder cells on the differentiation of embryonal carcinoma cells

Reversible effects of sodium butyrate on the differentiation of F9 embryonal carcinoma cells

We have studied effects of sodium butyrate on embryonal carcinoma F9 cell differentiation. In the presence of sodium butyrate, F9 cells underwent rapid and drastic morphological changes and expressed marked increases in mRNA levels of various differentiation markers. When sodium butyrate was removed from the cultures, all the examined phenotypes of F9 cell differentiation rapidly reverted to the characteristics of undifferentiated stem cells. However, under the same conditions, when cycloheximide or actinomycin D was added to the cultures, such phenotypic reversion was not observed, but high mRNA levels of the differentiation markers as well as altered cell morphology were retained. These results indicated that the effects of sodium butyrate on induction of teratocarcinoma cell differentiation were reversible and that de novo syntheses of some mRNA(s) and protein(s) were necessary for the reversion of differentiated cells to stem cells.

Suppression of c-mos expression in teratocarcinoma cells with a new type of inducer of differentiation, 3,5-di-tert-butylchalcone 4'-carboxylic acid

The treatment of 311 cells, a pluripotent mouse teratocarcinoma cell line, with a new type of inducer, 3,5-di-tert-butylchalcone 4'-carboxylic acid (Ch55), results in the suppression of the c-mos gene, accompanied by early marker changes associated with cell differentiation, i.e., the enhanced secretion of plasminogen activator and the decrease in peanut agglutinin receptors and glucose transport. This indicates that Ch55 is a potent inducer of teratocarcinoma cells and suppresses c-mos expression.

Spontaneous differentiation in the colonies of a nullipotent embryonal carcinoma cell line (F9)

Experiments were undertaken to reveal the spontaneous differentiation capacity of the nullipotent F9 embryonal-carcinoma (EC) cell line in colonies derived from single cells. Culture conditions which allowed the development of neuroblasts in colonies of the multipotent EC cell line (PCC3) were worked out, and comparative studies on neuroblast differentiation in PCC3 and F9 colonies were conducted. Neural-cell-specific silver impregnation, selective staining of cells having electrically excitable membranes with merocyanine 540 and the observation of nerve processes were considered as differentiation markers. The appearance of neuroblasts in F9 and PCC3 colonies could be detected from the 6th day after seeding. The development of neuroblasts was less prevalent in high-density cultures, especially in the case of F9. By the 8th day in differentiating colonies, PCC3 cells lost much of their colony-forming activity, while F9 cells preserved their original high plating efficiency, in spite of advanced differentiation. The determination of growth parameters during differentiation in colonies led to the conclusion that F9 cells had lost certain growth-control mechanisms which normally restrict the clonal growth of EC cells. It is suggested that the phenomenon of nullipotence may be analysed in terms of the coordinated regulation of proliferation and differentiation of EC cells.

Mode of cell surface marker changes during retinoic acid-induced differentiation in pluripotent embryonal carcinoma cells

Pluripotent teratocarcinoma cell line, 311, was cultured in the presence of retinoic acid (RA) and studied for the processes of early marker changes associated with cell differentiation. The cell populations that have lost peanut agglutinin (PNA), Lotus tetragonolobus agglutinin (LTA) or wheat germ agglutinin (WGA) receptor increased in proportion to the period since the start of RA treatment. The kinetics of the appearance of these receptor-negative cell populations suggests that the differentiating cells lose lectin receptors in the order of PNA, LTA and WGA. However, the changes in F9 antigen(s) and LTA receptor occurred at an equal frequency in PNA+ and PNA- cells, indicating that, although the loss of lectin receptors takes place in a distinct order, the change in each receptor itself proceeds independently of the state of other lectin receptors.

Induction of teratocarcinoma cell differentiation. Effect of the inhibitors of DNA synthesis

Induction of teratocarcinoma cell (F9) differentiation was studied by using inhibitors of DNA synthesis and several agents known to be differentiation inducers. Inhibition of DNA synthesis induced changes in cell surface marker F9 and stimulated the production of plasminogen activator (PA) in a manner that is dependent upon de novo synthesis of RNA and protein. The results thus indicate close association between inhibition of DNA synthesis and induction of cell differentiation. This approach will be useful in investigating the mechanism of teratocarcinoma cell differentiation.