Arsenic compounds in cancer therapy: mechanistic insights and antitumor activity.

Arsenic (As) is a naturally occurring metalloid with a dual nature, known both as an environmental hazard and a therapeutic agent. Despite its toxicity and role as a carcinogenic factor in various tumors, arsenic has been valued for its medicinal properties for centuries. Currently, arsenic trioxide (ATO), a prominent arsenic-based therapeutic, is a first-line treatment for acute promyelocytic leukemia (APL) when combined with all-trans retinoic acid. Beyond APL, growing evidence supports the therapeutic potential of arsenic compounds in treating other hematologic and solid tumors. Both inorganic and organic arsenic compounds exhibit anti-tumor effects through mechanisms such as promoting tumor cell differentiation, inhibiting angiogenesis, blocking oncogenic signaling pathways, inducing reactive oxygen species (ROS) production, and causing cell cycle arrest. This review highlights the applications of arsenic compounds in cancer therapy, focusing on their diverse mechanisms of action and recent advances in their use against various malignancies.