Indirect regulation of TFPI-2 expression by miR-494 in breast cancer cells
Indirect regulation of TFPI-2 expression by miR-494 in breast cancer cells
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DOI：
10.1038/s41598-020-61018-x
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发表时间：
2020-03-04
影响因子：
4.6
通讯作者：
Skretting, Grethe
中科院分区：
文献类型：
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作者：
Andresen, Marianne S.;Stavik, Benedicte;Skretting, Grethe
TFPI-2已被证明通过抑制细胞外基质降解参与乳腺癌发病机制，并且低水平与疾病进展相关。由于microRNA-494（miR-494）可防止乳腺癌进展，我们研究了miR-494是否参与MCF-7乳腺癌细胞中TFPI-2的调节。在用miR-494模拟物转染后，TFPI-2 mRNA和蛋白水平增加，并且TFPI-2 mRNA和miR-494水平在来自乳腺癌患者的肿瘤中呈正相关。在TFPI 2的3 '-非翻译区（UTR）中未鉴定出miR-494的特异性结合位点;然而，计算机模拟预测miR-494结合转录因子AHR和ELF-1的3'-UTR，其在TFPI 2启动子中具有潜在的结合位点。用miR-494模拟物转染后，ELF-1 mRNA下调，而AHR mRNA水平上调。ELF-1和AHR的敲低分别增加和减少TFPI-2 mRNA水平。当含有潜在AHR或ELF-1结合位点的TFPI-2启动子构建体与miR-494模拟物共转染时，观察到荧光素酶活性增加。总之，在MCF-7乳腺癌细胞中，TFPI-2 mRNA水平被miR-494上调，这很可能是通过miR 494靶向转录因子AHR和ELF-1的间接关联。这种关联在乳腺癌队列中得到了支持。
TFPI-2 has been shown to be involved in breast cancer pathogenesis by inhibiting extracellular matrix degradation, and low levels are associated with disease progression. As microRNA-494 (miR-494) protects against breast cancer progression, we investigated whether miR-494 is involved in the regulation of TFPI-2 in MCF-7 breast cancer cells. TFPI-2 mRNA and protein levels increased after transfection with miR-494 mimic, and TFPI-2 mRNA and miR-494 levels correlated positively in tumors from breast cancer patients. No specific binding sites for miR-494 in the 3'-untranslated region (UTR) of TFPI2 were identified; however, miR-494 was predicted in silico to bind 3'-UTR of the transcription factors AHR and ELF-1, which have potential binding sites in the TFPI2 promoter. ELF-1 mRNA was downregulated whereas AHR mRNA levels were upregulated after transfection with miR-494 mimic. Knockdown of ELF-1 and AHR increased and reduced TFPI-2 mRNA levels, respectively. Increased luciferase activity was seen when TFPI-2 promoter constructs containing the potential AHR or ELF-1 binding sites were co-transfected with miR-494 mimic. In conclusion, TFPI-2 mRNA levels were upregulated by miR-494 in MCF-7 breast cancer cells most likely by an indirect association where miR494 targeted the transcription factors AHR and ELF-1. This association was supported in a breast cancer cohort.