Lisa Barones

1. Introduction The inhibitor of growth 3 (ING3) belongs to a family of tumour suppressors encompassing five members (ING1–5), with the candidate tumour suppressor ING3 being the most evolutionarily distinctive [1]. The founding member, ING1, was discovered through differential screening of normal mammary epithelial cells and breast cancer cells [2]. Subsequently, ING2, 3, 4, and 5 were identified by applying bioinformatics approaches based upon sequence homology [3,4,5,6].