Effects of Selected Sulfhydryl Inhibitors on Nonhistone Chromosomal Proteins of HeLa Cells

Abstract

Effects of the SH inhibitor sodium iodoacetate, alone and with adjuncts menadiol diphosphate, sodium malonate, sodium fluoride and heparin, on incorporation of tryptophane-³ H into nonhistone chromosomal proteins of HeLa cells were examined. The drugs block incorporation of tryptophane-³ H into nonhistone chromosomal proteins far more than incorporation of leucine-³ H into total cellular proteins. Drug effects on thymidine phosphorylation and DNA synthesis in HeLa cells exceed corresponding effects on fibroblasts from normal healing wounds.

Selected Sulfhydryl Inhibitors Capable of Inducing Immunity against Cancer in Mice

“…Because selected SH inhibitors have been found to show marked activity against nonhistone chromosomal proteins of HeLa cancer cells [2], investigation of their activity at the cell surface appeared desirable from the histochemical studies [6]. For this, the scanning electron microscope offers certain advantages.…”

“…Such preferential effects for a few selected SH inhibitors have been seen both in sen sitivity tests monitoring drug effects on radioactive tracer incorporation to DNA, RNA, and protein, as well as clinically [1][2][3][4], Thus, Black et al [5] reported that patients obtaining regression of their solid tumors from use of the SH inhibitor iodoacetate plus adjuncts suffered no damage to circulating blood cells at the same dose of drug clearing blast cells from the circula tion of leukemic patients [5].…”