In addition, in vitro studies demonstrate that mouse embryonic flibroblasts (MEFs) derived from Casp2−/− mice become immortalized more readily and show enhanced sensitivity to transformation by oncogenes, including Ras and cMyc.9, 15 Interestingly though, not all types of tumours are affected by the loss of caspase-2,10, 16 suggesting that the nature of cell types involved (such as their proliferative capacity) may determine the participation of caspase-2 as a tumour suppressor. Here, CASP2 is linked to neoplasm.