Preserving fertility in young male cancer patients

Freezing testicular tissue from young boys who are not yet sexually mature before they undergo cancer treatment could help preserve their fertility say researchers in America. Spermatogonial stem cells (SSCs) found in testicular tissue are responsible for sperm production throughout adulthood and can be reproduced and transplanted back into the patient following treatment. “Our study addressed an important safety issue – whether cancer cells that might be present in testicular tissue samples can survive the process to replicate the sperm-producing stem cells,” said lead author Hooman Sadri-Ardekani from the Wake Forest Baptist Medical Center. “This is an important consideration because of the potential to reintroduce cancer into the patient.” Previous studies to eliminate cancer cells from biopsy tissue have shown contradictory results, so Sadri-Ardekani and his team developed a method to reproduce SSCs from a small tissue biopsy. Their process multiplies the original SSCs by 18,000-fold, so there are enough cells to transplant back into the patient when reaches adulthood. They took cells from the bone marrow of three patients with one of the most common childhood cancers – acute lymphoblastic leukaemia (ALL) – and put them through the cell reproduction process either alone, or with testicular cells obtained from other patients. Their results – published in Fertility and Sterility –  showed cancer cells were eliminated. ALL cells cultured separately did not survive beyond 14 days of culture, while ALL cells at a concentration of 40% in a mixture with testicular cells were entirely eliminated in 26 days of culture. “This pilot study showed that the culture system not only allowed for efficient propagation of sperm stem cells, but also eliminated ALL cells,” said Sadri-Ardekani, an instructor in urology and regenerative medicine. SSC transplantation has not yet been attempted in humans, but has successfully been performed in several species including monkeys, said Sadri-Ardekani. Before SSC transplantation can be trialled in humans, additional research is needed to see whether other types of leukaemia cells are also eliminated in the cell-propagation process. Eliminating acute lymphoblastic leukemia cells from human testicular cell cultures: a pilot study