Pre-clinical Trials for Female Fertility Preservation

描述(申请人提供)：早期卵巢衰竭和不孕不育是众所周知的抗癌治疗的副作用。虽然根除肿瘤的必要性是显而易见的，但这些治疗对卵巢等非靶标组织的长期影响是巨大的。不幸的是，保留女性癌症患者生育能力和卵巢功能的尝试收效甚微。在对小鼠的研究中，我们已经证明，神经酰胺的代谢物鞘氨醇-1-磷酸(S1P)可以在体内完全保护卵巢免受辐射损伤。长期的体内交配试验进一步表明，S1P在受辐射的雌性小鼠中保持了正常的生育水平，而在体内用S1P保护的卵母细胞受孕的后代没有证据表明存在跨代基因组损伤。通过使用人卵巢-小鼠异种移植模型，我们还表明，在体内将S1P直接注射到卵巢组织中可以防止辐射诱导的人原始卵泡和初级卵泡的丢失。尽管这些发现支持可以开发基于S1P的策略来对抗不孕症和卵巢衰竭，但仍需要解决两个主要问题。首先是确定S1P在接受抗癌治疗的非人类灵长类动物中保护卵巢功能和生育能力的安全性和有效性。第二是验证仅将S1P输送到卵巢的技术，从而防止S1P在全身获得有利于目标肿瘤细胞的S1P。为了实现这些目标，提出了以下具体目标：(1)确定S1P是否可以直接注射到恒河猴卵巢中，作为一种在体内保护性腺免受放射损伤的手段；(2)评估S1P保护的非人类灵长类卵巢中的卵母细胞受精和胚胎发生的能力；以及(3)评估在体内S1P保护的非人灵长类卵母细胞受孕的后代是否显示出繁殖的基因组损伤的证据。我们工作的目标是开发安全有效的策略，以保护体内的人卵巢免受抗癌治疗所造成的副作用损害。我们认为，本文讨论的已发表的和初步的数据强烈支持现在需要使用非人类灵长类动物作为模型来评估S1P在这方面的有效性以及传递机制。

DESCRIPTION (provided by applicant): Early ovarian failure and infertility are well-known side effects of anti-cancer treatments. While the need for tumor eradication is clear, the long-term consequences of these treatments on non-target tissues, such as the ovaries, are substantial. Unfortunately, attempts to preserve fertility and ovarian function in female cancer patients have met with little success. In studies with mice, we have shown that sphingosine-1- phosphate (S1P), a metabolite of the pro-apoptotic stress sensor ceramide, completely protects the ovaries from radiation-induced damage in vivo. Long-term in vivo mating trials have further shown that S1P preserves a normal level of fertility in irradiated female mice, and that offspring conceived with oocytes protected from radiation by S1P in vivo show no evidence of transgenerational genomic damage. With the use of a human ovarian-mouse xenograft model, we have also shown that injecting S1P directly into ovarian tissue can prevent radiation-induced loss of human primordial and primary follicles in vivo. Although these findings support that S1P-based strategies could be developed to combat infertility and ovarian failure, two major points still need to be addressed. The first is to establish the safety and efficacy of S1P for preserving ovarian function and fertility in non-human primates exposed to anti-cancer treatments. The second is to validate technologies to deliver S1P only to the ovaries, thereby preventing systemic availability of S1P that could benefit the tumor cells targeted for destruction. To accomplish these goals, the following Specific Aims are proposed: (1) to determine if S1P can be administered directly into the rhesus monkey ovary as a means to protect the gonads from radiotherapy-induced damage in vivo; (2) to evaluate the competency of the oocytes protected from radiotherapy by S1P in the non-human primate ovary for fertilization and embryogenesis; and (3) to assess if offspring conceived from non-human primate oocytes protected from radiotherapy by S1P in vivo show evidence of propagated genomic damage. The goal of our work is to develop safe and effective strategies for protecting human ovaries in vivo from the side-effect damage caused by anti-cancer therapies. We believe that the published and preliminary data discussed herein strongly support the need for now evaluating the efficacy of, as well as the delivery mechanisms for, S1P in this regard using the non-human primate as a model.