“…There is already some evidence for this since the MDA-MB468 breast cancer cell line, which lacks MI and RII mutation, has homozygous deletion of the DPC4 gene which was recently linked to the TGF-b pathway . SW480, which lacks MI and RII mutation, may be another example, since microcellmediated transfer of chromosome 18 restores responsiveness to TGF-b and suppresses its tumorigenicity (Goyette et al, 1992); this is consistent with restoration of DPC4 or another mad-related gene (Eppert et al, 1996), both located on chromosome 18q. Three other cell lines are monosomic for madgenes on chromosomes 5 (JV5-1), 15 (JV15-1, JV15-2) and 18 (DPC4 and JV18-1); KG-1 has monosomy 5, MDA-MB231 lacks both copies of chromosome 15, and SW837 is monosomic for chromosomes 15 and 18 MI, microsatellite instability; adenoca, adenocarcinoma; SCC, squamous cell carcinoma; poly-A, poly-adenine; del A, delete one A; del AA, delete two As; POS, positive; neg, negative; na, not analysed.…”