Lu Cuixiu, Zhao Huijun, Luo Chenshuo, Lei Ting, Zhang Man
Clinical Laboratory Medicine, Peking University Ninth School of Clinical Medicine, Beijing, China.
Clinical Laboratory Medicine, Capital Medical University, Beijing, China.
Transl Cancer Res. 2020 Sep;9(9):5418-5429. doi: 10.21037/tcr-19-2852.
Ferritin plays a key role in the development of prostate cancer (PCa). Our earlier studies showed that the knockdown of ferritin heavy chain (FTH) suppressed the migration and invasion of the prostate cancer cell line (PC3). However, the mechanisms behind FTH in the cell migration regulation of PCa have not been thoroughly investigated.
Isobaric tags for relative and absolute quantitation (iTRAQ) proteomics was used to analyze the protein expression in PC3 cells with FTH knockdown by small interfering RNAs and negative control cells. We subsequently ranked the differentially expressed proteins according to the change in expression. We further performed Gene Ontology (GO) analysis for the changing-expression protein. Finally, Western blot analysis was performed to determine the expression of the target protein.
Compared with the negative group, 420 proteins were downregulated, including proteins S100A4, S100P, and S100A2, while the expression of 442 protein was elevated in FTH-silencing PC3 cells (P<0.05, fold change >1.2). The mass spectrometry results showing decreased expression of protein S100A4, S100P, and S100A2 in the cells were further validated by Western blot (P<0.05). Levels of protein S100A4, S100A2, and S100P were reduced in FTH-silencing PC3 cells (P<0.05, fold change >1.6).
The downregulation of FTH expression reduced the level of protein S100A4, S100A2, and S100P, which all play a key role in the migration and invasion of tumor cells. Therefore, it is reasonable to assume that there are correlations between the expression of the , , and genes with FTH. Based on this research, FTH may be a new biomarker for the diagnosis of PCa.
铁蛋白在前列腺癌（PCa）的发展中起关键作用。我们早期的研究表明，铁蛋白重链（FTH）的敲低抑制了前列腺癌细胞系（PC3）的迁移和侵袭。然而，FTH在PCa细胞迁移调控中的作用机制尚未得到充分研究。
采用相对和绝对定量等压标签（iTRAQ）蛋白质组学技术，分析经小干扰RNA敲低FTH的PC3细胞和阴性对照细胞中的蛋白质表达。随后，根据表达变化对差异表达蛋白进行排序。我们进一步对表达变化的蛋白质进行基因本体（GO）分析。最后，进行蛋白质印迹分析以确定靶蛋白的表达。
与阴性组相比，420种蛋白质表达下调，包括S100A4、S100P和S100A2蛋白，而在FTH沉默的PC3细胞中442种蛋白质的表达升高（P<0.05，变化倍数>1.2）。蛋白质印迹进一步验证了质谱结果显示细胞中S100A4、S100P和S100A2蛋白表达降低（P<0.05）。FTH沉默的PC3细胞中S100A4、S100A2和S100P蛋白水平降低（P<0.05，变化倍数>1.6）。
FTH表达下调降低了S100A4、S100A2和S100P蛋白水平，这些蛋白在肿瘤细胞的迁移和侵袭中均起关键作用。因此，可以合理推测S100A4、S100A2和S100P基因的表达与FTH之间存在相关性。基于本研究，FTH可能是PCa诊断的新生物标志物。
