2 ppm selenium as Na2SeO3 and tracer 75-Se-selenite was administered to 615 mire inoculated with liver solid tumor six times over a 40-day period by ip. iniection. All mice were killed on the 45th day following tumor cell inoculation. The cytosols of RBC

liver and tumor cell were chromatographed on a Sephadex G-150 column separately. The 75-Se cpm

GPX activity and absorbance at 280 (or 540) nm of each collection were determined. The results showed that several Se-containing proteins except GPX exist in the cytosols; There are some differences about distribution of 75-Se in all of the three oytosols between the mice given nutritional or aaticarcinogenic selenium and with or without bearing tumor; The GPX and selenoproteins have also some; significant chauges. It is suggested chat these beh a-viors are probably responsible for this trace element’s anticarcinogenic properties