SLC6A8-mediated intracellular creatine accumulation enhances hypoxic breast cancer cell survival via ameliorating oxidative stress.
SLC6A8-mediated intracellular creatine accumulation enhances hypoxic breast cancer cell survival via ameliorating oxidative stress.
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SLC6A8介导的细胞内肌酸积累通过改善氧化应激增强缺氧乳腺癌细胞的存活
DOI：
10.1186/s13046-021-01933-7
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发表时间：
2021-05-14
期刊：
影响因子：
--
通讯作者：
Tu G
中科院分区：
文献类型：
--
作者：
Li Q;Liu M;Sun Y;Jin T;Zhu P;Wan X;Hou Y;Tu G
背景三阴性乳腺癌（TNBC）是乳腺癌中最具侵袭性的亚型，预后差，治疗选择有限。缺氧是TNBC的关键标志。代谢适应促进位于缺氧肿瘤区域内的TNBC细胞的进展。然而，它不是很好地理解关于精确的分子机制的调节代谢adaptionsbyhypoxia.MethodsRNA测序进行分析基因表达谱在MDA-MB-231细胞系（20%O2和1%O2）。实时定量PCR检测乳腺癌细胞和组织中编码肌酸转运蛋白的Slc 6a 8的表达。采用免疫组化法检测肿瘤组织中SLC 6A 8蛋白的表达。采用卡方检验和Kaplan-Meier分析评估临床病理相关性和总生存期。进行细胞活力测定和用膜联蛋白V/PI双染色的流式细胞术分析，以研究SLC 6A 8介导的肌酸摄取对缺氧TNBC细胞活力的影响。采用TNBC原位小鼠模型，观察肌酸对TNBC细胞凋亡的影响。SLC 6A 8在TNBC组织中显著过表达，其表达水平与TNM分期、组织学分级及总生存率密切相关。我们发现在缺氧条件下，p65/NF-κB可上调SLC 6A 8的转录，并介导细胞内肌酸的积累。SLC 6A 8介导的肌酸积累通过维持缺氧TNBC细胞中的氧化还原稳态来促进存活并抑制凋亡。此外，需要肌酸来促进异种移植小鼠模型中的肿瘤生长。从机制上讲，细胞内肌酸通过降低线粒体活性和氧消耗速率以减少细胞内活性氧物质的积累，最终激活AKT-ERK信号传导，其激活通过介导Ki-67和Bcl-2的上调来保护缺氧TNBC细胞的活力，结论SLC 6A 8介导的肌酸蓄积在促进TNBC进展中起重要作用，为SLC 6A 8高表达TNBC的治疗提供了一种潜在的治疗策略选择。
BackgroundTriple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer, with poor prognosis and limited treatment options. Hypoxia is a key hallmark of TNBC. Metabolic adaptation promotes progression of TNBC cells that are located within the hypoxic tumor regions. However, it is not well understood regarding the precise molecular mechanisms underlying the regulation of metabolic adaptions by hypoxia.MethodsRNA sequencing was performed to analyze the gene expression profiles in MDA-MB-231 cell line (20% O2and 1% O2). Expressions ofSlc6a8, which encodes the creatine transporter protein, were detected in breast cancer cells and tissues by quantitative real-time PCR. Immunohistochemistry was performed to detect SLC6A8 protein abundances in tumor tissues. Clinicopathologic correlation and overall survival were evaluated by chi-square test and Kaplan-Meier analysis, respectively. Cell viability assay and flow cytometry analysis with Annexin V/PI double staining were performed to investigate the impact of SLC6A8-mediated uptake of creatine on viability of hypoxic TNBC cells. TNBC orthotopic mouse model was used to evaluate the effects of creatine in vivo.ResultsSLC6A8 was aberrantly upregulated in TNBC cells in hypoxia. SLC6A8 was drastically overexpressed in TNBC tissues and its level was tightly associated with advanced TNM stage, higher histological grade and worse overall survival of TNBC patients. We found that SLC6A8 was transcriptionally upregulated by p65/NF-κB and mediated accumulation of intracellular creatine in hypoxia. SLC6A8-mediated accumulation of creatine promoted survival and suppressed apoptosis via maintaining redox homeostasis in hypoxic TNBC cells. Furthermore, creatine was required to facilitate tumor growth in xenograft mouse models. Mechanistically, intracellular creatine bolstered cell antioxidant defense by reducing mitochondrial activity and oxygen consumption rates to reduce accumulation of intracellular reactive oxygen species, ultimately activating AKT-ERK signaling, the activation of which protected the viability of hypoxic TNBC cells via mediating the upregulation of Ki-67 and Bcl-2, and the downregulation of Bax and cleaved Caspase-3.ConclusionsOur study indicates that SLC6A8-mediated creatine accumulation plays an important role in promoting TNBC progression, and may provide a potential therapeutic strategy option for treatment of SLC6A8 high expressed TNBC.
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DOI：
10.1042/bj20081386
发表时间：
2009-01-01
期刊：
The Biochemical journal
影响因子：
--
作者：
Murphy MP
通讯作者：
Murphy MP
影响因子：
13.8
作者：
Patra, Krushna C.;Hay, Nissim
通讯作者：
Hay, Nissim
分子对肿瘤细胞缺氧的反应。
影响因子：
37.3
作者：
Kunz, Manfred;Ibrahim, Saleh M
通讯作者：
Ibrahim, Saleh M
影响因子：
19
作者：
Ackerman, Daniel;Simon, M. Celeste
通讯作者：
Simon, M. Celeste
DOI：
10.1186/s40880-018-0288-x
发表时间：
2018-04-25
期刊：
Cancer communications (London, England)
影响因子：
--
作者：
Koppula P;Zhang Y;Zhuang L;Gan B
通讯作者：
Gan B