Acid DNase and neutral RNase were enzymes known to be associated with processes involved in carcinogenesis and suppression of cancer. These two enzymes were isolated and partially purified in the osteosarcom tissue of bone to find out whether the enzymes isolated were specific to the sarcoma. Also studied were inhibitory actions of protein inhibitors and polynucleotides on acid DNase and neutral RNase to evaluate how these enzymes were regulated in the sarcoma tissue.
Activities of acid DNase, neutral RNase and RNase inhibitor were markedly increased and the positive rate of each of the enzymes and inhibitor as a marker for osteosarcoma was high, suggesting the acid DNase, the RNase and the inhibitor could be used as a biochemical marker for the osteosarcoma.
Chromatographical analyses revealed that the acid DNase of osteosarcoma tissue was separated in a single peak which was greater than that isolated in control tissue of bone. The neutral RNase in osteosarcoma tissue was separated into 5 isozymes, of which two isozymes were specific to the sarcoma, the other two isozymes were greater in activity(activated) and the rest of two isozymes isolated in the control tissue of bone was disappeared.
RNase inhibitor activity was detected in all of the five isozymes isolated from the osteosarcoma tissue. The ratio of inhibitor/RNase in the RNase isozyme I fraction was the least of the five isozyme fractions isolated from the sarcoma tissue, indicating that the degree of increment in the inhibitor activity was lesser in the RNase isozyme fraction 1.
The acid DNase and RNase isozyme I isolated from the osteosarcoma tissue was inhibited by nucleic acids and polynucleotides, the degree of inhibition being changed with base sequence of the polynucleotides studied.
The present study was shown that (1) the acid DNase activity known to be associated with carcinogenesis was greatly increased, (2) the RNase isozyme I activity suggested to be related with suppression of cancer was also greatly increased, (3) the inhibitor activity linked with the isozyme I was decreased relatively and that (4) these enzyme activities were inhibited by nucleic acids and polynucleotides studied. The results indicated that acid DNase and RNase isozyme I were associated with carcinogenesis and suppression of osteosarcoma, these actions being regulated not only by protein inhibitors, but also by sequence of polynucleotides.
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