Dichloroacetic acid (DCA) drug molecule. Computer model of dichloroacetic acid, or dichloroacetate, a chemical compound and acid whose salts may prove to be an effective anti-cancer agent. The body usually kills damaged cells by apoptosis (cell suicide) but this involves the mitochondria, which are often damaged in the cells of a malignant tumour, and so the mechanism fails. A study published in January 2007 found that DCA restored mitochondrial function, thus restoring apoptosis, killing cancer cells in vitro and shrinking tumours in rats. No clinical trials in humans have yet been conducted. Atoms are colour-coded: carbon (yellow), hydrogen (white), chlorine (green) and oxygen (red).