November 2, 2012
Stem Cells Help Preserve Sperm of Male Cancer Patients
[WATCH VIDEO: Stem Cells Show Promise For Treating Infertility]
Connie K. Ho for redOrbit.com — Your Universe Online
Researchers from the University of Pittsburgh School of Medicine and Magee-Womens Research Institute (MWRIF) recently discovered that a stem-cell based approach to treat infertility was successful in non-human primates and could possibly be used by cancer patients who have become infertile as a result of chemotherapy.
In particular, patients who undergo chemotherapy or radiation therapy often become infertile due to the treatments that damage dividing cells; these cells include both cancer cells and spermatogonial stem cells (SSCs), stem cells that later on become sperm.
Before undergoing cancer therapy, some patients have the option to cryopreserve their sperm and use the cells later on to have children. However, while adult males have this option, prepubertal boys do not as they have not yet reached the age where they produce mature sperm and, as such, cancer treatments can cause them to become permanently infertile.
"Men can bank sperm before they have cancer treatment if they hope to have biological children later in their lives," explained senior investigator Kyle Orwig, an associate professor in the Department of Obstetrics, Gynecology, and Reproductive medicine at the Pitt School of Medicine, in a press release. "But that is not an option for young boys who haven't gone through puberty, can't provide a sperm sample, and are many years away from thinking about having babies."
The preclinical study was recently published in the journal Cell Stem Cell.
"This is the first study to demonstrate that transplanted spermatogonial stem cells can produce functional sperm in higher primates," remarked Orwig, who also serves as an investigator at the Magee-Womens Research Institute, in the statement. "This is an important step toward human translation."
With the new findings, the scientists believe that the young male patients can possibly preserve their SSCs prior to having cancer therapy. These cells can later on be transplanted when they end their cancer treatment and when they reach the point of sexual maturity. The team of investigators examined this possible option by cyropreserving SSCs from monkeys prior to treatment of a chemotherapy drug.
Following treatment, they injected the SSCs into the testes of the monkeys with an ultrasound-guided technique and discovered that the cells were able to form sperm in nine out of the 12 adult animals as well as three out of the five prebuteral animals once they reached maturity. In another test, the spermatogonial stem cells from other monkeys were transplanted into animals that were infertile. The sperm was able to fertilize 81 egg cells, and produce normal embryos that grew into the morula and blastocyst stages.
"This study demonstrates that spermatogonial stem cells from higher primates can be frozen and thawed without losing their activity, and that they can be transplanted to produce functional sperm that are able to fertilize eggs and give rise to early embryos," continued Orwig in the statement.
Based on the results of the study, the researchers believe that new stem cell-based therapies will become viable options in the future and help boys have their own children later on.
"These patients and their families are the pioneers that inspire our research and help drive the development of new medical breakthroughs," concluded Orwig in the statement.