The use of cytokine granulocyte colony-stimulating factor (G-CSF) is associated with enhanced spermatogenic recovery following busulfan chemotherapy and may play a role in helping to preserve fertility in male patients with cancer, according to researchers from the University of Texas at San Antonio. They are now reporting in Reproductive Biology and Endocrinology that employing G-CSF treatment to protect spermatogenesis from cancer treatments has the potential to revolutionize male fertility preservation in a manner that can be rapidly translated to the clinic. They point out that various forms of G-CSF are already approved by the U.S. Food and Drug Administration.1
The studies examining G-CSF as a protective agent so far have only utilized adult animal models. The authors reported that the applicability to prepubertal patients with cancer will first need to be established by examining the influence of G-CSF on spermatogenic recovery in immature animals. So, even though the drugs are already on the pharmacy shelf there are many unanswered questions about dosing and duration of benefit.
The researchers emphasize that it is too early to apply G-CSF clinically as a means of protecting or restoring fertility in humans until more studies are completed. They noted that there needs to be a more thorough examination of efficacy and mechanism of action. Currently, men and boys who have undergone puberty can ensure future fertility by cryobanking sperm. However, for pre-pubertal boys this is not an option, the authors indicated.
1. Kotzur T, Benavides-Garcia R, Mecklenburg J, et al. Granulocyte colony-stimulating factor (G-CSF) promotes spermatogenic regeneration from surviving spermatogonia after high-dose alkylating chemotherapy. Reprod Biol Endocrinol. 2017 Jan 11;15(1):7. doi: 10.1186/s12958-016-0226