Biological activity and redistribution of nucleolar proteins of two different cell lines treated with cis-dichloro-1,2-propylenediamine-N,N,N',N'-tetraacetato ruthenium (III) (RAP).

The interaction of a newly synthesized antitumor complex cis-dichloro-1,2-propylenediamine-N,N,N',N'-tetraacetato ruthenium (III) (RAP) with DNA was investigated in vitro through a number of techniques including comet assay, immunoprecipitation, and immunolocalization of certain nucleolar proteins (the upstream binding factor (UBF) and fibrillarin) involved in DNA transcription, rRNA processing, and ribosomal assembly. The results showed that RAP binds to the DNA of two cell lines (H4 and Hs-683) causing a delay in cell proliferation rate leading to a number of cellular modifications. These modifications include DNA-damage assessed by the single cell gel electrophoresis method (comet assay) and variation in the expression of nucleolar proteins; UBF was more abundant in RAP treated cells, this was explained by the high affinity of this protein to DNA modified by RAP. On the other hand, fibrillarin was found in less quantities in RAP treated cells which was explained by a de-regulation of the ribosomal machinery caused by RAP.

EFFECTS OF HIGH CONCENTRATIONS OF SINGLE AMINO ACIDS ON THE PROLIFERATION OF TUMOR CELLS IN VITRO / 营养学报

The effects of high concentrations (1-5mmol/L) of different amino acids in Hanks solution on the proliferation of Ehrlich ascites tumor cells and Walker 256 carcinosarcoma cells were examined. In order to demonstrate the inhibitory effect of some amino acids at high concentration level, the further studies were conducted on Ehrlich ascites tumor cells, human hepatoma cells and lung cancer cells, using Eagle's MEM as culture medium. The possible toxicity of the high concentrations of single amino acids to normal tissue cells was tested on mouse bone marrow cells. Although some amino acids exhibited a significant inhibitory effect, the responses of different tumor cells to the high concentrations of different amino acids were not entirely similar. Moreover, the effects presented by some amino acids on Ehrlich ascites tumor cells in Hanks solution could be diminished or eliminated in Eagle's MEM. Among the aromatic and basic amino acids, only the tryptophan was found to be inhibitory to the multiplication of mouse bone marrow cells at high concentration levels in vitro.