Biochemical Study of Nuclei Isolated From Normal Lung and Lung Tumors. I. Isolation of Nuclei and Characterization of Nuclear RNA

Summary

With the citric acid procedure, nuclei were isolated from “normal” lung tissue and lung tumors: squamous cell carcinoma, adenocarcinoma, and anaplastic carcinoma. The purity of the isolated nuclei was defined by light and electron microscopy. The RNA/DNA ratios of nuclei in neoplastic lung tissue differed significantly from those of the controls. Although the base compositions of nuclear DNA from normal and neoplastic lung tissues did not differ significantly, the nucleotide composition of nuclear RNA from the normal lungs differed from that of the tumors; i.e., the uridylic acid content was significantly lower in the tumors than in the normal lungs, and the cytidylic acid content was significantly higher. On the other hand, the nucleotide compositions of nuclear RNA of 4 different normal lungs used as controls were not significantly different nor were those of the lung tumors.