DHICA (5,6-Dihydroxyindole-2-carboxylic acid) is an intermediate in melanin synthesis and a component of eumelanin, as well as acting as a moderate potency agonist of GPR35. In the U2OS cell line, DHICA demonstrates the ability to induce β-arrestin translocation signaling with an EC50 value of 23.2 μM. Additionally, it plays a significant role in promoting and protecting against DNA damage.