Anti-tumor Effects and Induction of Apoptosis by Realgar Bioleaching Solution in Sarcoma-180 Cells in Vitro and in Vivo

TCMs Realgar (also named “Xiong-Huang” in Chinese) is the ore of sulfide mineral Realgar, which consists of a series of arsenic-containing metal sulfides (AS4S4) (Xuemin, 2000; National Pharmacopoeia Committee 2004). Pure realgar is an orange-red crystalline mineral. The spatial structure of realgar is analogous to that of sulfur (S8), in which 4 arsenic atoms regularly replace 4 of the 8 sulfur atoms to form a similar ring, but the monoclinic crystal structure of realgar is different from the orthorhombic symmetry of sulfur. Realgar is soft and sectile; and usually occurs in granular, compact, or powder form. Considerable documents and clinical observations have established that arsenic-related medication can produce potent anti-cancer effects possibly by inducing cell apoptosis (Daopei et al., 1998; Mengchang et al., 2002; Xiaoou, 2006). Arsenicals have been known as toxins and paradoxically as therapeutic agents. In the 1970s, Chinese physicians revived the medicinal use of arsenicals as anticancer agents. Distinguished success was observed in the treatment of acute promyelocytic leukemia (APL) with arsenic trioxide (ATO). The FDA approved ATO injection in the year 2000 for the treatment