AND-1在卵巢癌顺铂耐药中的作用及分子机制研究

Cisplatin resistance is a major challenge in the treatment of ovarian cancer patients in clinic, but the underlying molecular mechanisms remain largely unknown. It was reported that nucleotide excision repair (NER) and homologous recombination repair (HRR) pathways are associated with cisplatin resistance of cancer by repairing cisplatin-induced DNA damage. Previous study demonstrated that AND-1 (acidic nucleoplasmic DNA-binding protein) plays multiple roles in the maintenance of genomic stability. Our preliminary study indicate that AND-1 interacts with NER protein XPA and HRR protein CTIP; AND-1 depletion by shRNA increases the chemosensitivity of SKVO3 ovarian cancer to cisplatin. Based on our findings and preliminary data, we hypothesize that AND-1 contributes to cisplatin resistance by promoting NER and HRR in ovarian cancer. To test this hypothesis, we will aim to address the functional roles and underlying mechanisms for AND-1 in platin resistance of ovarian cancer in in vitro and in vivo experimental models. The key questions to be answered in this study include the extent to which AND-1 levels contribute to cisplatin resistance of ovarian cancer cells; and how AND-1 contributes to cisplatin resistance by regulating NER and HRR in ovarian cancer cells. This study will be significant, as it may provide new approaches as well as innovative therapeutic strategies to overcome cisplatin resistance in ovarian cancer.

卵巢癌顺铂耐药是目前卵巢癌研究领域亟待解决的关键科学问题之一。已有的研究结果表明，核苷酸切除修复和同源重组修复对顺铂耐药起重要作用。酸性核质DNA结合蛋白AND-1通过多种机制调控基因组的稳定性。我们最近的研究发现，AND-1与NER蛋白XPA以及HRR蛋白CTIP相互作用。shRNA干扰AND-1表达能够增加SKVO3卵巢癌细胞对顺铂治疗的敏感性，但是其作用机制尚不清楚。我们推测AND-1可能同时作用于NER和HRR两条DNA损伤修复系统，从而增强细胞顺铂耐药。本研究拟在前期工作基础上，采用体内、外实验模型，系统深入地研究AND-1与卵巢癌顺铂耐药之间的关系及分子机制。拟解决的关键问题包括AND-1的表达对卵巢癌细胞顺铂耐药的影响；AND-1如何调控NER和HRR系统促进卵巢癌顺铂耐药。研究成果将为发现逆转卵巢癌顺铂耐药的新方法和治疗策略提供重要理论依据。

顺铂耐药是成功治疗卵巢癌的主要障碍。核酸切除修复（NER）和同源重组修复(HRR)促进顺铂耐药。DNA结合蛋白AND-1参与HRR，调控基因组稳定性，但AND-1是否参与卵巢癌顺铂耐药尚不清楚。本课题研究发现：①AND-1在卵巢癌细胞高表达，敲除AND-1增加A2780、SKOV3卵巢癌细胞对顺铂的敏感性。AND-1在顺铂耐药细胞株（A2780/CR、SKOV3/CR）表达显著升高，敲低A2780/CR细胞AND-1表达可逆转细胞顺铂耐药。②AND-1聚集于γ射线和UV诱导DNA损伤位点，并与HRR蛋白CTIP以及NER蛋白XPF、DNA Polδ等相互作用。③敲除AND-1抑制CTIP和XPF、DNA Polδ等在DNA损伤后位点的聚集，抑制细胞HRR和NER，促进顺铂诱导的细胞凋亡。AND-1通过调控HRR和NER通路促进DNA损伤修复，增强卵巢癌顺铂耐药，敲除AND-1增强细胞对顺铂治疗的敏感性。研究结果有助于我们进一步了解顺铂耐药的分子机制，并为AND-1作为卵巢癌治疗的分子靶标提供重要理论依据。.另外，我们筛选出了多个抗卵巢癌顺铂耐药细胞的小分子化合物，如土木香内脂（Alantolactone）和杂氮环卡宾铂配合物（MeOPtI2Py）等，对卵巢癌耐药细胞有较好的杀伤作用，具有一定的研究和开发价值。.