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。如果化疗药物的个体毒性是已知的，患者可以咨询卵巢损伤的可能性和保留生育能力的必要性。此外，如果开发出药物卵巢保护策略，将不需要手术干预来保持生育能力，从而降低伴随的风险和成本。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，此外还测试了药理学方法在异种移植模型中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，因为它是年轻妇女最常见的恶性肿瘤。具体目标是：（1）使用卵泡群体的现有和新出现的标记物来确定常用的乳腺癌化疗方案对卵巢储备的影响。将在化疗前和化疗后获得窦卵泡计数、抑制素B、抗苗勒管激素和FSH/雌二醇测量值，随访2.0-4.5年。(2)测定化疗药物对人卵巢的损伤程度并探讨其作用机制。具有人卵巢组织异种移植物的免疫缺陷小鼠将用常用和新兴药物或溶剂处理;卵泡密度的变化以及通过预裂解半胱天冬酶-3表达定量的凋亡性卵泡死亡的程度将用于测量影响。还将通过定量血管评估方法和活体染料注射研究微血管损伤导致卵泡损失的替代机制。此外，我们将调查是否双链DNA断裂诱导在存活的原始卵泡的ATM通路蛋白参与DMA修复的分析。(3)确定细胞死亡抑制剂S1 P是否保护原始卵泡池免受化疗诱导的损伤，并确定其机制是否涉及通过S1 P受体对原始卵泡的直接作用或对卵巢微血管的保护。这些目标将在短期和长期异种移植模型中进行研究，其中不仅测试原始卵泡存活，而且测试S1 P保护的原始卵泡发育成窦期并产生有能力的卵母细胞的潜力。

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.