Characterization and prevention of chemotherapy-induced damage to ovarian reserve

描述（由申请人提供）：化疗引起的卵巢功能衰竭是一个日益严重的公共卫生问题，对生活质量有重大影响。如果已知化疗药物的个别毒性，可以告知患者卵巢损伤的可能性和保留生育能力的必要性。此外，如果开发了卵巢药物保护策略，就不需要手术干预来保持生育能力，从而降低了伴随的风险和成本。该项目的长期目标是通过开发更准确的卵巢储备评估策略和异种移植模型来提高我们对化疗诱导的卵巢衰竭风险的理解，以及在异种移植模型中测试药物方法预防化疗诱导的卵巢储备损伤的有效性。该提案的重点是乳腺癌，因为它是年轻女性中最常见的恶性肿瘤。具体目的是：(1)利用现有和新出现的卵泡群体标记物确定常用乳腺癌化疗方案对卵巢储备的影响。通过2.0-4.5年的随访，将获得化疗前后的窦卵泡计数、抑制素- b、抗苗勒管激素和卵泡刺激素/雌二醇测量。(2)测定化疗药物对人卵巢的损伤程度并确定其损伤机制。移植了人类卵巢组织的免疫缺陷小鼠将使用常用的和新兴的药物或载体进行治疗；通过预裂caspase-3表达测定的卵泡密度变化以及凋亡的卵泡死亡程度将被用来衡量影响。我们还将通过定量血管评估方法和活体染料注射来研究微血管损伤导致卵泡丢失的另一种机制。此外，我们将通过分析参与DMA修复的ATM途径蛋白来研究存活的原始卵泡是否会诱导双链DMA断裂。(3)确定细胞死亡抑制剂S1P是否可以防止化疗引起的原始卵泡池损伤，并确定其机制是否涉及通过S1P受体直接作用于原始卵泡，还是保护卵巢微血管。这些目标将在短期和长期异种移植模型中进行研究，在这些模型中，不仅要测试原始卵泡的存活，还要测试受S1P保护的原始卵泡发育到心房期并产生合格卵母细胞的潜力。

DESCRIPTION (provided by applicant): Chemotherapy-induced ovarian failure is a growing public health problem with a major impact on quality of life. If individual toxicity of chemotherapy agents is known, patients can be counseled about the likelihood of ovarian damage and the need for fertility preservation. Moreover, if pharmacological ovarian protection strategies are developed, there will be no need for surgical interventions to preserve fertility, thus reducing concomitant risks and costs. The long term goal of this project is to improve our understanding of the risks of chemotherapy-induced ovarian failure by developing more accurate ovarian reserve assessment strategies and xenografting models, in addition to testing the effectiveness of pharmacological approaches to prevent chemotherapy induced damage to ovarian reserve in a xenograft model. The proposal focuses on breast cancer since it is the most common malignancy in young women. The specific aims are: (1) To determine the impact of commonly used breast cancer chemotherapy regimens on ovarian reserve using existing and emerging markers of the follicle population. Antral follicle counts, Inhibin-B, anti-mullerian hormone, and FSH/estradiol measurements will be obtained pre-and post-chemotherapy with a 2.0-4.5 year follow-up. (2) To measure the degree and determine the mechanism of damage caused by chemotherapeutics in human ovary. Immunodeficient mice with human ovarian tissue xenografts will be treated with commonly used and emerging agents, or the vehicle; changes in follicle density, as well as the extent of apoptotic follicular death as quantified by pre-cleaved caspase-3 expression will be used to measure the impact. An alternative mechanism of follicular loss by microvascular damage will also be investigated by quantitative vascular assessment methods and intra-vital dye injection. Moreover, we will investigate whether double strand DMA breaks are induced in the surviving primordial follicles by the analysis of ATM pathway proteins involved in DMA repair. (3) To determine whether a cell death inhibitor S1P protects against chemotherapy-induced damage to the primordial follicle pool, and ascertain whether the mechanism involves direct effects on primordial follicles via S1P receptors, or protection of ovarian microvasculature. These aims will be studied in short-and long-term xenograft models where not only the primordial follicle survival but the potential of S1P- protected primordial follicles to develop into antral stages and produce competent oocytes will be tested.