Controle genético das células-tronco humanas cultivadas

Abstract

Stem cells have a high capacity of self-regeneration, as well as a potential to differentiate into several cell types. These cells can be classified as embryonic or adult. In spite of having inherent properties of stem cells, mesenchymal cells show a certain degree of difficulty to establish cultures. This might induce a loss of the expression of the telomerase enzyme which is considered to be a biological clock or an indicator of the senescence of the cells. The most current and intriguing question for researchers is whether the presumed division potential of cultivated stem cells, over a period of time could result in an accumulation of genetic alterations and consequently, in a neoplastic process. For this reason, cytogenetic techniques are very important to guarantee the control and safety of cultivated stem cells to be used in human therapy. Structural chromosomal alterations, such as for example, deletions, translocations and inversions represent an important mechanism by which cells might gradually transform in a neoplastic process. Thus, these chromosomal alterations could result in an abnormal expression of the genes and lead to cancer.