Stimulation of DNA Synthesis with Histones from Tumor Tissues. ∗

Summary

The histones isolated from different tumor tissues enhance the incorporation of H³ thymidine into DA of various organs of C₃H mice, especially into spleen. When isolated from embryonic tissues, the histones promote such incorporation to a lesser extent. Additional purification of these histones leads to a decrease in this enhancement. The histones isolated from normal organs do not have any effect.

The author wishes to thank Dr. K. B. DeOme, Cancer Research Laboratory, Univ. of California, for kindly supplying C₃H mice, C₃H/Sx mammary carcinoma and hcpaloma 134; Mr. S. Kass and Mr. R. H. Levenson, Virus Laboratory, Univ. of California, for kindly supplying Shope papillomatosis and Rous sarcoma; and Dr. L. Hnilica, Biochemistry Department, Baylor Univ., who made available the histone from Walker carcinoma. The author also wishes to express his gratitude to Dr. W. M. Stanley for helpful support throughout this work.