We have previously shown that withdrawal of folic acid led to metabolic reprogramming and a less aggressive phenotype in a mouse cell model of triple-negative breast cancer (TNBC). Herein, we evaluate the effects of folic acid withdrawal on transcriptomic profiles in these cells. Murine cell lines were originally derived from a pool of spontaneous mammary tumors grown in MMTV-Wnt1 transgenic mice. Based on their differential molecular characteristics and metastatic potential, these cell lines were previously characterized as non-metastatic epithelial (E-Wnt), non-metastatic mesenchymal (M-Wnt) and metastatic mesenchymal (metM-Wntliver) cells. Using custom two-color 180K Agilent microarrays, we have determined gene expression profiles for three biological replicates of each subtype kept on standard medium (2.2 μM folic acid) or folic acid-free medium for 72 h. The analyses revealed that more genes were differentially expressed upon folic acid withdrawal in M-Wnt cells (1884 genes; Benjamini-Hochberg-adjusted P-value <0.05) compared to E-Wnt and metM-Wntliver cells (108 and 222 genes, respectively). Pathway analysis has identified that type I interferon signaling was strongly affected by folic acid withdrawal, with interferon-responsive genes consistently being upregulated upon folic acid withdrawal in M-Wnt cells. Of note, repressed interferon signaling has been established as one of the characteristics of aggressive human TNBC, and hence reactivation of this pathway may be a promising therapeutic approach. Overall, while our study indicates that the response to folic acid withdrawal varies by molecular subtype and cellular phenotype, it also underscores the necessity to further investigate one-carbon metabolism as a potential therapeutic means in the treatment of advanced TNBC.

中文翻译：

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叶酸戒断对鼠三阴性乳腺癌细胞系转录组谱的影响。

我们先前已经表明，在三阴性乳腺癌（TNBC）的小鼠细胞模型中，叶酸的撤回导致代谢重编程和攻击性较低的表型。在本文中，我们评估了叶酸戒断对这些细胞中转录组谱的影响。鼠细胞系最初源自在MMTV-Wnt1转基因小鼠中生长的自发性乳腺肿瘤库。基于它们的差异分子特征和转移潜能，这些细胞系以前被表征为非转移上皮（E-Wnt），非转移间充质（M-Wnt）和转移间充质（metM-Wntliver）细胞。使用定制的双色180K安捷伦微阵列，我们确定了保存在标准培养基中的每种亚型的三个生物学重复的基因表达谱（2。2μM叶酸）或不含叶酸的培养基72小时。分析显示，与E-Wnt和metM-Wntliver细胞（分别为108和222个基因）相比，M-Wnt细胞（1884个基因； Benjamini-Hochberg调整后的P值<0.05）中的叶酸撤除后，差异表达的基因更多。 ）。途径分析已经确定，I型干扰素信号转导受叶酸戒断的强烈影响，在M-Wnt细胞中叶酸戒断后干扰素反应性基因始终被上调。值得注意的是，抑制的干扰素信号已被确定为侵略性人TNBC的特征之一，因此重新激活该途径可能是一种有前途的治疗方法。总体而言，虽然我们的研究表明，对叶酸戒断的反应因分子亚型和细胞表型而异，