Tang Xiaojiang, Deng Chaowei, Liu Yang, Pu Shengyu, Zheng Qi, Zhou Yudong, Hao Na
Department of Breast Surgery, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaan'xi Province, 710061, China.
Department of Cell Biology and Genetics, Institute of Genetics and Developmental Biology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, 710061, China.
J Transl Med. 2025 Mar 25;23(1):370. doi: 10.1186/s12967-025-06364-y.
The ZBTB (zinc finger and BTB domain-containing) protein family comprises a significant class of transcription factors that interact with various corepressors and histone/protein-modifying enzymes. This interaction facilitates chromatin remodeling and the regulation of gene silencing or activation, thereby playing a crucial role in cancer progression. However, the biological effects and molecular mechanisms of ZBTB6, a member of the ZBTB family, in cancer remain unclear.
The expression levels of ZBTB6 in breast cancer (BC) were investigated through public database queries, real-time quantitative PCR (qRT‒PCR), and Western blot analysis. The effects of ZBTB6 on BC cell viability were assessed via MTT assays. Flow cytometry was utilized to analyze the cell cycle distribution and apoptosis. Additionally, cell-derived xenograft experiments were conducted to study the impact of ZBTB6 on BC growth in vivo. The relationship between ZBTB6 and the ARHGAP6 promoter was evaluated via bioinformatics predictions, chromatin immunoprecipitation (ChIP) coupled with qRT‒PCR, and luciferase reporter assays.
Our study demonstrated that ZBTB6 is highly expressed in primary BC specimens and cell lines and strongly correlated with tumor grade and poor prognosis. In vitro, ZBTB6 knockdown inhibited cell viability and cell cycle progression while promoting apoptosis; conversely, ZBTB6 overexpression elicited the opposite effects. In vivo, the inhibition of ZBTB6 expression in BC cells significantly suppressed tumor growth. Furthermore, we identified ARHGAP6 as a transcriptional target downstream of ZBTB6, with ZBTB6 binding to the promoter region of ARHGAP6 to repress its transcription. Notably, ARHGAP6 can exert an inhibitory effect on tumors by attenuating STAT3 activity. Our results indicate that ZBTB6 overexpression enhances the STAT3 signaling pathway, whereas ARHGAP6 overexpression counteracts the effects of ZBTB6 overexpression in BC cells.
These findings suggest that ZBTB6 promotes breast cancer progression by repressing the transcription of ARHGAP6 and activating the STAT3 signaling pathway. Consequently, ZBTB6 may serve as a potential prognostic biomarker or therapeutic target for breast cancer patients.
含锌指和BTB结构域（ZBTB）的蛋白质家族是一类重要的转录因子，可与多种共抑制因子以及组蛋白/蛋白质修饰酶相互作用。这种相互作用有助于染色质重塑以及基因沉默或激活的调控，从而在癌症进展中发挥关键作用。然而，ZBTB家族成员ZBTB6在癌症中的生物学效应和分子机制仍不清楚。
通过公共数据库查询、实时定量PCR（qRT-PCR）和蛋白质印迹分析，研究ZBTB6在乳腺癌（BC）中的表达水平。通过MTT试验评估ZBTB6对BC细胞活力的影响。利用流式细胞术分析细胞周期分布和凋亡情况。此外，进行细胞源性异种移植实验，以研究ZBTB6对BC体内生长的影响。通过生物信息学预测、染色质免疫沉淀（ChIP）结合qRT-PCR以及荧光素酶报告基因试验，评估ZBTB6与ARHGAP6启动子之间的关系。
我们的研究表明，ZBTB6在原发性BC标本和细胞系中高表达，且与肿瘤分级和不良预后密切相关。在体外，敲低ZBTB6可抑制细胞活力和细胞周期进程，同时促进凋亡；相反，过表达ZBTB6则产生相反的效果。在体内，抑制BC细胞中ZBTB6的表达可显著抑制肿瘤生长。此外，我们确定ARHGAP6是ZBTB6下游的转录靶点，ZBTB6与ARHGAP6的启动子区域结合以抑制其转录。值得注意的是，ARHGAP6可通过减弱STAT3活性对肿瘤发挥抑制作用。我们的结果表明，ZBTB6过表达增强STAT3信号通路，而ARHGAP6过表达可抵消ZBTB6过表达对BC细胞的影响。
这些发现表明，ZBTB6通过抑制ARHGAP6的转录并激活STAT3信号通路促进乳腺癌进展。因此，ZBTB6可能作为乳腺癌患者潜在的预后生物标志物或治疗靶点。
