Resident stem cells, which are already committed to become specific tissue types, are responsible for digit regeneration in mice; however, this does not rule out the possibility that terminally differentiated tissue can dedifferentiate into resident stem cells.
C2C12 myotubes, which are mature differentiated multinucleated muscle cells, have been shown to dedifferentiate when induced to express Msx-1 , the microtubule-binding molecule myoseverin , and the small molecule, reversine , or when treated with extracts from regenerating newt limbs .
Taken together, the available data suggest that the extraordinary regenerative potential of holothurian visceral organs is mostly due to the ability of specialized cells to dedifferentiate
and rebuild the lost structures through proliferation and migration.
He and his colleagues have recently shown that some factor present in blood serum, newt or any other kind, can induce newt muscle cells to dedifferentiate
. The muscle cells of nonregenerating vertebrates don't respond to the serum, however, indicating that they are not sensitive to this still unidentified factor.
At the early stages of regeneration, these two cell types dedifferentiate
. As myoepithelial cells dedifferentiate
, their myofilaments form dense spindle-like structures (SLSs) (Dolmatov, 1992; Dolmatov et al., 1996).
After settlement, the larval flagellated cells dedifferentiate into a simple cell mass on the substratum; thereafter they differentiate again into the three principal cell types of a juvenile sponge.
After settlement, the flagellated cells soon loose their flagellum and dedifferentiate. The dedifferentiation is apparently triggered by the settlement of the larva.
Indeed, this has led some experts to consider STUMP to be within the spectrum of BPH, (10) although most agree that it is a distinct entity as it often rapidly recurs, is seen in younger men, occurs in the peripheral zone, may infiltrate locally, and may dedifferentiate
to or coexist with stromal sarcoma.
Cellular origin of cancer: dedifferentiate
or stem cell maturation arrest?
It is also thought that malignant transformation of osteochondromas mainly in the cartilage cap develops through a stepwise fashion first into low-grade chondrosarcoma then dedifferentiates
into high-grade sarcoma that may eventually become fibrosarcomas or osteosarcomas .
With the egg cytoplasm attempting to take control of the nucleus, the skin cell apparently "dedifferentiates
" and can then redifferentiate into new kinds of tissue.
Holland, "PDGF autocrine stimulation dedifferentiates
cultured astrocytes and induces oligodendrogliomas from and oligoastrocytomas neural progenitors and astrocytes in vivo," Genes and Development, vol.