Two Novel Organoselenium Compounds Induce Apoptosis In Tumor Cell Line, And Effect On Mice

Selenium is an important trace element involved in different physiological functions of human body. According to some laboratory data and many epidemiological studies, it is shown that selenium plays an important role in preventing and controling cancers. This is mainly achieved through strengthening the function of immune system, affecting the cell proliferation and the metabolism of selenium-containing proteins, and influencing tumor metastasis and inducing the apoptosis of tumor.Study shows the anticancer function of selenium is due to its chemical formation. Although a number of selenium compounds are chemopreventively effective, organic selenium compounds have drawn great attention, because of their low toxicity and significant anticancer effects. This study investigates two kinds of new chemosynthesis organoselenium compounds, xylose selenite and sucrose selenite, which can induce apoptosis in tumor cells. Selenite is used as a negative control in comparisons with these two selenocompounds (xylose selenite and sucrose selenite).First, the reserch focuses on testing inhibition effects of xylose selenite and sucrose selenite on four types of cell lines (293T, Hela, HepG2, SMMC-7221) and their effects on inducing apoptosis. The results indicate that neither of the two organoselenium compounds has an obvious inhibition effect on the non-tumor cell line-293T. However, for tumor cell lines such as Hela, HepG2 and SMMC-7221, the inhibition effects are significant and among these three cell lines, SMMC-7221 cell line appears a typical apoptosis induced by some pharmacological action.The next is to study the effects of three different selenocompounds (selenite, xylose selenite and sucrose selenite) on inducing apoptosis of SMMC-7221 cell line. From the study, the latter two have been found with obvious effects upon this issue. SMMC-7221 cells exhibites mitochondrial injury and cell death and mainly apoptosis.The last study is conducted for toxicity tests of the three above-mentioned selenocompounds through the response from BALB/c mice. The present study reveals that, compared with selenite, xylose selenite and sucrose selenite possess better efficacy in increasing the activities of antioxidant enzymes but have much lower toxicity. The above results show that compared with selenite, xylose selenite and sucrose selenite, which can induce the apoptosis of SMMC-7221 cell line, have more significant inhibition effects on tumor cells but less toxicity in the organism level.