Intriguingly, some genes firstly identified in Drosophila as tumor suppressor genes, such as discs large 1 (dlg1), lethal (2) giant larvae (l(2)gl), and brain tumor (brat) (Gateff, 1978), were later uncovered as ACD regulators (Albertson and Doe, 2003; Bello et al., 2006; Betschinger et al., 2006; Bowman et al., 2008; Ohshiro et al., 2000; Peng et al., 2000; Lee et al., 2006), further supporting the connection between compromised ACD and tumorigenesis. The gene discussed is ACD; the disease is neoplasm.