(7) Third, the de-differentiation
theory indicates that existing papillary, follicular, medullary, and anaplastic thyroid carcinoma de-differentiate into SCC.
The finding is the first to show that mammalian adult stem cells can march backward along the developmental timeline in a process called de-differentiation
to become more primitive in response to environmental signals.
of papillary thyroid carcinoma into squamous cell carcinoma.
Exact origin of melanoma in GCTs is unknown but these may occur from transformation of dermal elements or de-differentiation
of germ cells to melanomas.
It occurs more commonly in the extremities, and cases of primary undifferentiated pleomorphic sarcoma of the penis are very difficult to find.[sup.9] El Hayek and colleagues[sup.10] suggest that one possible explanation could be the occurrence of de-differentiation
. On the other hand, the tumour could have been pleomorphic from the start.
GBM frequently arises de novo, but may develop from diffuse or anaplastic astrocytomas that undergo de-differentiation
. (4) Glioblastoma is the most common brain tumour, accounting for 12 - 15% of intracranial neoplasms and 50 - 60% of astrocytic tumours.
However, no experiments published have directly demonstrated this de-differentiation
process, so Li and his research team remained skeptical.
Stem cell scientists in China have used a technique known as de-differentiation
to re-engineer cells to a more primitive state that increases cell survival rates and offers greater potential for clinical use.
The unit prevents de-differentiation
of adult cardiomyocytes, encourages pre-commitment of stem cells toward certain muscle phenotypes and is suited for cardiac tissue engineering.
In particular, he discusses the definition and classification of cancer, cellular carcinogenesis as a monoclonal multi-step threshold phenomenon, the five types of genetic and molecular changes leading to cancer, causes of cancer, cellular changes associating malignant transformation or de-differentiation
, tumor recurrence and metastasis, tumor markers, natural inhibitors of the multi-stage carcinogenesis, and biochemical bases of current anti-cancer treatments.
Having learnt some lessons from SCNT (cloning), we need to be very cautious in generating stem cells by directed differentiation (IPS) or de-differentiation
for cell therapy to treat diseases.