Hospices Civils de Lyon, Service de Radiologie, Centre Hospitalier Lyon Sud, Pierre-Bénite, France.
Int J Radiat Biol. 2011 Nov;87(11):1103-12. doi: 10.3109/09553002.2011.608410. Epub 2011 Sep 19.
To assess in vitro mammographic radiation-induced DNA damage in mammary epithelial cells from 30 patients with low (LR) or high (HR) family risk of breast cancer.
Spontaneous and radiation-induced DNA double-strand breaks (DSB) were quantified by using immunofluorescence of the phosphorylated H2AX histone (γH2AX) in different conditions of mammography irradiation (2, 4, 2 + 2 mGy).
HR patients showed significantly more spontaneous γH2AX foci than LR patients (p = 0.014). A significant dose-effect was observed, with an exacerbation in HR patients (p = 0.01). The dose repetition (2 + 2 mGy) provided more induced and more unrepaired DSB than 2 mGy and 4 mGy, and was exacerbated in HR (p = 0.006).
This study highlights the existence of DSB induced by mammography and revealed by γH2AX assay with two major radiobiological effects occurring: A low-dose effect, and a LOw and Repeated Dose (LORD) effect. All these effects were exacerbated in HR patients. These findings may lead us to re-evaluate the number of views performed in screening using a single view (oblique) in women whose mammographic benefit has not properly been proved such as HR patients.
评估 30 名低（LR）或高（HR）乳腺癌家族风险患者的乳腺上皮细胞中乳腺摄影辐射诱导的 DNA 损伤。
通过免疫荧光法检测不同乳腺摄影照射条件下（2、4、2+2mGy）磷酸化 H2AX 组蛋白（γH2AX），定量检测自发和辐射诱导的 DNA 双链断裂（DSB）。
HR 患者的自发 γH2AX 焦点明显多于 LR 患者（p=0.014）。观察到显著的剂量效应，HR 患者加剧（p=0.01）。剂量重复（2+2mGy）比 2mGy 和 4mGy 诱导更多的未修复 DSB，且在 HR 中加剧（p=0.006）。
本研究强调了乳腺摄影诱导的 DSB 的存在，并通过 γH2AX 检测揭示了两种主要的放射生物学效应：低剂量效应和低剂量重复（LORD）效应。所有这些效应在 HR 患者中加剧。这些发现可能导致我们重新评估在未适当证明乳腺摄影获益的情况下，如 HR 患者，使用单次（斜位）视图进行筛查的视图数量。
