Algoma District Cancer Program, Sault Area Hospital, Sault Ste. Marie, ON, Canada; Section of Internal Medicine, Division of Clinical Sciences, Northern Ontario School of Medicine, Sudbury, ON, Canada.
Hematol Oncol Stem Cell Ther. 2021 Mar;14(1):16-26. doi: 10.1016/j.hemonc.2020.08.005. Epub 2020 Sep 26.
Vitamin D is a steroid hormone that exerts its actions through ligation of the vitamin D receptor (VDR), a transcription factor of the nuclear receptor family. VDR has not only physiologic actions in calcium metabolism but also several other cellular effects through extensive binding to the DNA and modification of genome expression. In cancer, it has neoplasia-suppressive effects and various mechanisms of action mediating cancer cell inhibition have been described. Vitamin D deficiency has been linked to increased risk of breast cancer. A role of the vitamin once the disease has been diagnosed is also probable.
A systematic review and meta-analysis of studies that report on vitamin D levels (in the form of its main circulating metabolite, 25-hydroxyvitamin D [25-OHD]) in patients with newly diagnosed breast cancer was performed. Outcomes of interest included the levels of serum 25-OHD in patients with breast cancer, those of matched controlled, in studies that included controls, as well as respective percentages of patients and controls with deficient and insufficient 25-OHD levels.
A total of 25 studies (10 with controls and 15 without controls) provided data on the outcomes of interest. Populations from all continents, besides Australia, were represented in the studies. The mean level of 25-OHD in patients with breast cancer was 26.88 ng/mL (95% CI 22.8-30.96 ng/mL) and the mean level of 25-OHD in control patients was 31.41 ng/mL (95% CI 19.31-43.5 ng/mL). In the patients with breast cancer group, 45.28% (95% CI 24.37%-53.51%) had levels of 25-OHD below 20 ng/mL, whereas this percentage was 33.71% (95% CI 21.61%-45.82%) in controls. Similarly, 67.44% (95% CI 48.32%-86.55%) of patients with breast cancer had a baseline level of 25-OHD below 30 ng/mL, whereas this percentage was 33.71% (95% CI 21.61%-45.82%) in controls.
A high prevalence of vitamin D insufficiency is observed in patients with newly diagnosed breast cancer and may be linked pathophysiologically with breast cancer development or progression. Therapeutic benefits may be provided by manipulation of the vitamin D pathway in breast cancer.
维生素 D 是一种类固醇激素，通过与维生素 D 受体（VDR）结合发挥作用，VDR 是核受体家族的转录因子。VDR 不仅在钙代谢中具有生理作用，而且通过与 DNA 的广泛结合和对基因组表达的修饰，还具有多种其他细胞效应。在癌症中，它具有抗肿瘤作用，并且已经描述了介导癌细胞抑制的各种作用机制。维生素 D 缺乏与乳腺癌风险增加有关。一旦诊断出这种疾病，维生素也可能发挥作用。
对报告新诊断乳腺癌患者维生素 D 水平（以其主要循环代谢物 25-羟维生素 D [25-OHD] 的形式）的研究进行了系统评价和荟萃分析。感兴趣的结果包括乳腺癌患者的血清 25-OHD 水平、有对照的研究中的对照患者的水平、包括对照患者的研究中的各自百分比的患者和对照患者维生素 D 水平不足和不足。
共有 25 项研究（10 项有对照，15 项无对照）提供了感兴趣的结果数据。来自各大洲的人群，除了澳大利亚，都在研究中。乳腺癌患者的 25-OHD 平均水平为 26.88ng/mL（95%CI 22.8-30.96ng/mL），对照组患者的 25-OHD 平均水平为 31.41ng/mL（95%CI 19.31-43.5ng/mL）。在乳腺癌患者组中，45.28%（95%CI 24.37%-53.51%）的 25-OHD 水平低于 20ng/mL，而对照组为 33.71%（95%CI 21.61%-45.82%）。同样，67.44%（95%CI 48.32%-86.55%）的乳腺癌患者基线 25-OHD 水平低于 30ng/mL，而对照组为 33.71%（95%CI 21.61%-45.82%）。
新诊断为乳腺癌的患者中维生素 D 不足的发生率很高，这可能与乳腺癌的发生或发展在病理生理学上有关。通过对乳腺癌患者的维生素 D 途径进行干预，可能会带来治疗益处。
