武汉云克隆科技股份有限公司

Abstract：

Background: Recent studies suggest vitamin D (VD) plays a role in cancer cell growth, with evidence indicating that a deficiency can lead to higher disease risk and a poorer outcome. Activation of the vitamin D receptor (VDR) by the active form of VD (calcitriol) leads to the regulation of anti-cancer genes. Therefore, we propose that VDR could be targeted as a potential therapeutic for treatment of breast cancer. 

Methods: The effects of calcitriol and inecalcitol (Hybrigenics, Paris) on breast cancer (BC) cell growth were investigated in 16 cell lines (TN = 7, Her2+ = 5, luminal = 4) and 7 cell lines (TN = 3, Her2+ = 2, luminal = 2), respectively. Cytotoxicity was determined by MTT assays and cell proliferation by colony formation assays (CFA). VDR expression was measured by ELISA (USCN Life Science Inc.). 

Results: IC50 concentrations for treatment with calcitriol, across the 16 cell lines ranged from 0.12 µM to > 100 µM, using the MTT assay. These IC50 values were validated by CFA with a significant correlation between the 2 assays (p = 0.0046, r = 0.898). Sensitivity to calcitriol was higher in ER+ compared to ER- cell lines (p = 0.0454) but was independent of HER2 status (p = 0.8181). VDR expression in the cell lines varied from undetectable to 10 pg/mg. A significant correlation was found between VDR levels and IC50 value (p = 0.0076, r = -0.6401). IC50 concentrations for treatment with the low calcemic-inducing VD analogue inecalcitol ranged from 4.2 nM to 54.4 nM across 7 cell lines. Sensitivity to inecalcitol was higher in ER+ compared to ER- cell lines (p = 0.0092), but like with calcitriol, was independent of HER2 status (p = 0.4745). A significant correlation was found between IC50 values for inecalcitol and calcitriol (p = 0.0231, r = 0.8571). However, depending on the cell line, inecalcitol was approximately 14 to > 50 fold more sensitive than calcitriol (p = 0.0006).

Conclusions: These preclinical results suggest that calcitriol and inecalcitol can inhibit breast cancer cell line growth. Since inecalcitol, is considerably more potent than calcitriol and has low calcemic potential, it should be further investigated as a treatment for breast cancers expressing VDR.

摘要：

背景：最近的研究表明维生素D（VD）在癌细胞生长中起作用，有证据表明缺乏VD可导致更高的疾病风险。 VD的活性形式（钙三醇）通过激活维生素D受体（VDR）可调节抗癌基因。因此，我们建议VDR可作为治疗乳腺癌的潜在治疗药物。

方法：在16个细胞系（TN = 7，Her2 + = 5，luminal = 4）和7个细胞系中分别研究钙三醇和乙醇胺（Hybrigenics，Paris）对乳腺癌（BC）细胞生长的作用。通过MTT法和集落形成分析（CFA）细胞增殖来确定细胞毒性。通过ELISA（USCN Life Science Inc.）测量VDR表达。

结果：使用MTT测定法，对16个细胞系的钙三醇治疗的IC50浓度范围为0.12μM - >100μM。以上方法测定的IC50值由CFA测定进行验证，结果两种检测方法的结果之间有显着相关性（p = 0.0046，r = 0.898）。 ER +细胞系对钙三醇的敏感性高于ER-细胞系（p = 0.0454），但与HER2状态无关（p = 0.8181）。 VDR在细胞系中的表达范围从不可检测到10pg / mg。 VDR水平与IC50值之间存在显着相关性（p = 0.0076，r = -0.6401）。在7个细胞系中，用低钙血症诱导的VD类似物——非钙化醇治疗的IC50浓度范围为4.2nM - 54.4nM。与ER-细胞系相比，ER +对inecalcitol的敏感性更高（p = 0.0092），但与钙三醇类似，与HER2状态无关（p = 0.4745）。结果显示inecalcitol和calcitriol的IC50值有显着相关性（p = 0.0231，r = 0.8571）。但是，基于细胞系的不同，inecalcitol比calcitriol（p = 0.0006）的灵敏度高约14至50倍。

结论：这些临床前期结果表明，钙三醇和inecalcitol可以抑制乳腺癌细胞系的生长。由于inecalcitol比calcitriol有效性更强，且产生低血钙的可能性更高，因此应该对其作为表达VDR的乳腺癌的治疗物进行进一步的研究。

使用试剂原文信息：

Methods: The effects of calcitriol and inecalcitol (Hybrigenics, Paris) on breast cancer (BC) cell growth were investigated in 16 cell lines (TN = 7, Her2+ = 5, luminal = 4) and 7 cell lines  respectively. Cytotoxicity was determined by MTT assays and cell proliferation by colony formation assays (CFA). VDR expression was measured by ELISA (USCN Life Science Inc.).