DNA methylation is associated with the risk factors of breast cancer. However, the impact of the reproductive and non-reproductive risk factors of breast cancer on p14/ARF methylation is not well known. Therefore, we investigated the relationships between p14/ARF methylation percentage and risk factors of breast cancer including age, family history, obesity, and reproductive risk factors in 120 breast cancer-free subjects; 60 women with a first-degree family history of breast cancer and 60 age-matched women with no family history of breast cancer. Extracted DNA from the whole blood was bisulfite-treated by EZ DNA modification kit. Quantitative methylation of p14/ARF was analyzed by methylation-specific PCR then methylation percentage of p14/ARF was calculated. P14/ARF methylation percentage was not related to any of the risk factors of breast cancer except age. Our study showed that p14/ARF methylation percentage was significantly higher in females with age ≥ 40 years than in females with age < 40 years (p=0.029). Also, a positive significant correlation between the p14/ARF methylation percentage and age was detected (r = 0.285, p = 0.014). Furthermore, univariate regression analysis showed that the age is independently associated with high p14/ARF methylation percentage (β = 1. 46, p = 0.029). Among healthy females, the age is strongly linked to the peripheral p14/ARF methylation percentage. The present study suggests that p14/ARF methylation is not associated with other breast cancer risk factors. These results need oncoming research on a large cohort to define the interactions between p14/ARF methylation and the risk factors of breast cancer.

中文翻译：

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健康女性 p14/ARF 甲基化的决定因素：与乳腺癌生殖和非生殖危险因素的关联

DNA甲基化与乳腺癌的危险因素有关。然而，乳腺癌的生殖和非生殖风险因素对 p14/ARF 甲基化的影响尚不清楚。因此，我们在 120 名无乳腺癌受试者中研究了 p14/ARF 甲基化百分比与乳腺癌危险因素（包括年龄、家族史、肥胖和生殖危险因素）之间的关系；60 名有一级乳腺癌家族史的女性和 60 名无乳腺癌家族史的同龄女性。从全血中提取的 DNA 用 EZ DNA 修饰试剂盒进行亚硫酸氢盐处理。通过甲基化特异性 PCR 分析 p14/ARF 的定量甲基化，然后计算 p14/ARF 的甲基化百分比。除年龄外，P14/ARF 甲基化百分比与任何乳腺癌风险因素均无关。我们的研究表明，年龄 ≥ 40 岁女性的 p14/ARF 甲基化百分比显着高于年龄 < 40 岁女性（p=0.029）。此外，检测到 p14/ARF 甲基化百分比与年龄之间存在显着正相关（r = 0.285，p = 0.014）。此外，单变量回归分析表明，年龄与高 p14/ARF 甲基化百分比独立相关（β = 1. 46，p = 0.029）。在健康女性中，年龄与外周 p14/ARF 甲基化百分比密切相关。本研究表明 p14/ARF 甲基化与其他乳腺癌风险因素无关。