Stem Cell Researchers Reprogram Normal Tissue Cells Into Cells With Same Properties As Embryonic ...

What about the cloning issue?

The original method of making stem cells was to take an egg from a woman and fertilize the egg with a donor sperm. The fertilized egg is allowed to divide several times in cell culture resulting in four to sixteen stem cells.

But, by taking an adult skin cell, introduce a small number of genes which direct the "committed" adult skin cell to revert all the way back to an embryonic stem, might make it easier to clone a human by this technology than from embryonic stem cell technology.

Embryonic stem cell technology is based on introducing a somatic cell nucleus into a potentially hostile environment of an egg from a different person, who is not a clone of the individual from which the somatic cell nucleus was obtained. There is no reason a cell can't be reprogrammed to return to precisely the state it was in which it was a primitive embryonic stem cell or the original stem cell, the fertilized egg itself.

This new technology stem cell would have the same genetic material and the same capabilities as the embryonic stem cell technology. The cells are created by introducing a handful of genes to reprogram the DNA of an adult cell so that the cell reverts back to the state of a newly fertilized egg. It would genetically be a clone of the original fertilized egg.

In terms of being totally identical, save for the 4 extraneous genes introducted to turn the non-pluripotent skin (somatic) cell back into a true embryonic stem cell, these genes would either silence themselves spontaneously or could be silenced using already available technology.

Interesting! What happens now?

In the meantime.....

Scientists study cancer cell movement

There was a very interesting article on embryonic stem cells and cancer reported in the May 16, 2007 issue of Molecular Biology of the Cell. British scientists have made a breakthrough in understanding how cancers spread, which could lead to new methods of fighting the disease.

The University of Manchester study used embryonic stem cells to investigate how some tumors are able to migrate to other parts of the body, thus making cancer treatments more difficult.

Christopher M. Ward, the lead researcher, and colleagues studied a crucial change what makes cancer cells able to start moving and spread into other tissues. Known as the epithelial-mesenchymal transition, this crucial change was observed in the early embryo, theorizing that embryonic stem cells might undergo a similar process.

They have shown embryonic stem cells spontaneously change in a manner that is remarkably similar to the epithelial-mesenchymal transition. They lose the proteins that cells use to bind to each other and have other protein alterations that are characteristic of spreading cancer cells.

Studying such cells, researchers have identified a novel component of the transition process and expect to identify other factors involved in cancer cell spread, hopefully leading to new cancer therapies.

Epigenetics To Shape Stem Cell Future

Everyone hopes that one day stem cell-based regenerative medicine will help repair diseased tissue. Before then, it may be necessary to decipher the epigenetic signals that give stem cells their unique ability to self-renew and transform them into different cell types.

The hype over epigenetic research is because it opens up the possibility of reprograming cells. By manipulating epigenetic marks, cells can be transformed into other cell types without changing their DNA. It is simply a question of adding or removing the chemical tags involved.

Stem cells rely heavily on epigenetic signals. As a stem cell develops, chemical tags on the DNA or its surrounding histone proteins switch genes on or off, controlling a cell’s fate.

Epigenetics and stem cell biology are such clear strengths in the European research community. European labs are breaking ground in both the epigenetic and stem cell arenas. To build on this expertise and stimulate the exchange on novel technologies, the European Science Foundation organized the EuroSTELLS workshop.

Epigenetic research has benefited tremendously from genome technology, and work in the field is advancing at break-neck speed.“If you think that the first enzymes controlling histone methylation were found in 2001, the acceleration is tremendous,” says Robert Feil, a EuroSTELLS researcher based at the CNRS Institute of Molecular Genetics in Montpellier.“We are making good use of past investments in genome sequencing. In the next five years the technology will be ten times faster than it has been so far.”

New high-throughput approaches and refined analytical techniques promise to fill in some big gaps in understanding how epigenetic tags define a stem cell and how they can be manipulated. With this knowledge on board, researchers will be boosting the odds that one day stem cell therapies will reach the clinic.

EuroSTELLS is the European Collaborative Research (EUROCORES) programme on “Development of a Stem Cell Tool Box” developed by the European Science Foundation.

Source: European Science Foundation

To Evade Chemotherapy, Some Cancer Cells Mimic Stem Cells

http://www.aacr.org/home/public--media/news-r...

Using the CellSearch System techique that quantifies circulating tumor cells, researchers had shown that chemotherapy with Taxol causes a massive release of cells into the circulation, while at the same time reducing the size of the tumor, explaining that complete pathologic responses do not correlate well with improvements in survival.

Circulating tumor cells (CTCs) are cancer cells that have detached from solid tumors and entered the blood stream. This can begin the process of metastasis, the most life-threatening aspect of cancer. To metastasize, or spread cancer to other sites in the body, CTCs travel through the blood and can take root in another tissue or organ.

In this stem cell research, anti-cancer treatments often effectively shrink the size of tumors, but some might have the opposite effect, actually expanding the small population of cancer stem cells that then are capable of metastasizing.

Even before the advent of the CellSearch technique, it had been observed in "cell death" cell culture assays, that there was an increase in the number of metabolic activity of mitochondria of the surviving cells from Taxol therapy, even in cases where the majority of the cells are being killed by Taxol. It may indeed give clinical response (tumor shrinkage), however, these are mostly short-lived and relapses after a response are often dramatic.

Well, here it is!

Study Reports Successful Cloning of Human Embryo Using Adult DNA

http://stemcells.alphamedpress.org/cgi/reprin...