AIM2 and melanoma: Absent in melanoma 2 (AIM2), discovered in melanoma in 1997,1 was originally described as a novel member of interferon (IFN)‐inducible PYHIN proteins, which contains four members in humans (AIM2, IFI16, IFIX, and MNDA) and 13 homologous proteins (e.g., Aim2, p202, p204, and p205) in mice.2