Department of Obstetrics and Gynecology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China.
Int J Gynecol Cancer. 2018 Oct;28(8):1514-1519. doi: 10.1097/IGC.0000000000001334.
This study aimed to assess the relationship between BRCA1 gene methylation, PD-L1 protein expression, and the clinicopathologic features of sporadic ovarian cancer (OC).
Bisulfite pyrosequencing and immunohistochemistry were used to detect BRCA1 gene methylation and PD-L1 protein expression, respectively, in tumor tissues from 112 patients with sporadic OC. Their levels were analyzed against clinicopathologic characteristics and prognosis using standard statistical methods.
Twenty percent (22/112) of the OC cases exhibited BRCA1 gene hypermethylation. The frequency of BRCA1 hypermethylation was significantly higher in serous OC (25%) than in nonserous OC (8%; P < 0.05). No significant correlations were discovered between BRCA1 hypermethylation and age, menstrual status, tumor location, stage, lymph node metastasis, and prognosis (P > 0.05). Among the 112 OC cases, 59% (66/112) cases were positive for PD-L1 protein expression. No significant difference existed between PD-L1 expression and age, menstrual status, histological type, tumor location, stage, lymph node metastasis, and prognosis (P > 0.05). Moreover, no correlation existed between BRCA1 methylation and PD-L1 expression (P > 0.05, r = 0.002).
This is the first study linking BRCA1 hypermethylation variability to PD-L1 protein expression and the clinicopathologic features of OC. The data demonstrated that an epigenetic alteration of BRCA1 was closely associated with serous OC. The expression of PD-L1 was unrelated to the clinicopathologic features or BRCA1 hypermethylation in sporadic OC.
本研究旨在评估 BRCA1 基因甲基化、PD-L1 蛋白表达与散发性卵巢癌（OC）临床病理特征之间的关系。
采用亚硫酸氢盐焦磷酸测序和免疫组织化学方法分别检测 112 例散发性 OC 肿瘤组织中 BRCA1 基因甲基化和 PD-L1 蛋白表达。采用标准统计学方法分析其与临床病理特征和预后的关系。
20%（22/112）的 OC 病例存在 BRCA1 基因高甲基化。BRCA1 高甲基化在浆液性 OC（25%）中的频率明显高于非浆液性 OC（8%；P<0.05）。BRCA1 高甲基化与年龄、月经状态、肿瘤位置、分期、淋巴结转移和预后之间未发现显著相关性（P>0.05）。在 112 例 OC 病例中，59%（66/112）的病例 PD-L1 蛋白表达阳性。PD-L1 表达与年龄、月经状态、组织学类型、肿瘤位置、分期、淋巴结转移和预后之间无显著差异（P>0.05）。此外，BRCA1 甲基化与 PD-L1 表达之间无相关性（P>0.05，r=0.002）。
这是首次将 BRCA1 高甲基化的变异性与 OC 的 PD-L1 蛋白表达和临床病理特征联系起来的研究。数据表明，BRCA1 的表观遗传改变与浆液性 OC 密切相关。PD-L1 的表达与散发性 OC 的临床病理特征或 BRCA1 高甲基化无关。
