A 1999 genetic study suggests that the variations represent differentiated populations with limited gene flow between them, and that the three subspecies comprise a single evolutionarily significant unit.
Following the expression of these genes, induction of markers representing differentiated cell types can be observed, such as Pdx1 (foregut endoderm), Nkx2-5 (cardiac mesoderm) and βH1 globin (yolk sac erythroid cells) [2].
Thus, CSCs may represent differentiated descendants of COCs.
The presumed pathway would imply successively lichen sclerosus, hyperplasia, and lower atypia representing differentiated type VIN, then leading to carcinoma.
From the same patients, DNA was extracted from whole blood and CD44- and ALDH1Low cells, representing differentiated tumor cells.
The switching between different stable states (representing differentiated or pathological phenotypes) requires that the activity/expression of several "signaling" molecules change in concert.
By contrast, the crescent and mechanoreceptor cells expressed six3 and thus, by molecular identity, appear to represent differentiated cell types of the surrounding apical plate.
ES and iPS cells are in a balanced stable state that can shift to multiple other states representing differentiated cell types [ 5, 6].
There is thus no support for an ecological gradient hypothesis, in which the forms represent differentiated ecotypes which maintain some degree of gene flow.
Simple residual cysts with no soft tissue nodules in the wall usually represent differentiated teratoma whereas residual masses which are partially solid and cystic often contain undifferentiated active cancer as well as areas of necrosis, fibrosis and differentiated tissue.
