New stem cell production method could clear way for anticancer gene therapy

Fuente: http://www.stemcellsportal.com/content/new-stem-cell-production-method-could-clear-way-anticancer-gene-therapy

A new study released in STEM CELLS Translational Medicine suggests a new way to produce endothelial progenitor cells in quantities large enough to be feasible for use in developing new cancer treatments.

Endothelial progenitor cells (EPCs) are rare stem cells that circulate in the blood with the ability to differentiate into the cells that make up the lining of blood vessels. With an intrinsic ability to home to tumors, researchers have focused on them as a way to deliver gene therapy straight to the cancer. However, the challenge has been to collect enough EPCs for this use.

This new study, by researchers at the Institute of Bioengineering and Nanotechnology, National University of Singapore and Zhejiang University led by Shu Wang, Ph.D., explored whether human induced pluripotent stem cells (iPSCs) could provide the answer. iPSCs, generated from adult cells, can propagate indefinitely and give rise to every other cell type in the body, much like human embryonic stem cells, which are considered the gold standard for stem cell therapy.

“However, human iPS cells can be generated relatively easily through reprogramming, a procedure that circumvents the bioethical controversies associated with deriving embryonic stem cells from human embryos,” Dr. Wang said.

After inducing human iPS cells to differentiate into the EPCs, the research team compared the stability and reliability of the induced EPCs with regular EPCs by injecting them into mice with breast cancer that had metastasized (traveled) to the lungs. The results showed that their induced EPCs retained the intrinsic ability to home to tumors, just as regular EPCs do. They also did not promote tumor growth or metastasis.

“We next tested the induced EPCs’ therapeutic potential by infusing them with an anticancer gene and injecting them into the mice,” Dr. Wang said. “The results indicated that the tumors were reduced and the animals’ survival rates increased.

“Since this approach may use patient's own cells to prepare cellular therapeutics and is based on non-toxic immunotherapy, it holds potential for translation to clinical application and may be particularly valuable as a new type of anti-metastatic cancer therapy.”

“With the increasing potential of using EPCs as cancer therapeutics, it is important to have a reliable and stable supply of human EPCs, said Anthony Atala, M.D., editor of STEM CELLS Translational Medicine and director of the Wake Forest Institute for Regenerative Medicine. “This study demonstrates the feasibility of generating EPs from early-passage human iPS cells.”