Xia Jiyi, Yu Xiaolan, Tang Li, Li Gang, He Tao
Research Center for Drug and Functional Food, Luzhou Medical College, Luzhou, Sichuan 646000, P.R. China.
Department of Obstetrics and Gynecology, The Affiliated TCM Hospital of Luzhou Medical College, Luzhou, Sichuan 646000, P.R. China.
Oncol Rep. 2015 Jul;34(1):103-10. doi: 10.3892/or.2015.3979. Epub 2015 May 13.
Purinergic signaling has been implicated in the regulation of many cellular processes. A high concentration of ATP has been observed in the tumor microenvironment, suggesting a possible role of extracellular ATP in tumor progression. The P2X7 receptor, which belongs to the ligand-gated ion channel receptor family, is involved in tumor development and metastasis. In the present study, we found that extracellular ATP stimulated the invasion and migration of human T47D breast cancer cells, in a dose-dependent manner. BzATP (ATP analogue), but not ADP, also promoted invasion and migration. We further found that the P2X7 receptor was highly expressed in the T47D cells. After knockdown of the P2X7 receptor, ATP-stimulated invasion and migration were markedly inhibited. Moreover, activation of the P2X7 receptor by ATP downregulated the protein level of E-cadherin and upregulated the production of MMP-13. In addition, ATP time-dependently induced the activation of AKT via the P2X7 receptor, and the AKT pathway was required for the ATP-mediated invasion and migration. Taken together, our results revealed that activation of the P2X7 receptor by ATP promotes breast cancer cell invasion and migration, possibly via activation of the AKT pathway and regulation of E-cadherin and MMP-13 expression. Therefore, the P2X7 receptor may be a useful therapeutic target for the treatment of breast cancer.
嘌呤能信号传导与许多细胞过程的调节有关。在肿瘤微环境中观察到高浓度的ATP,提示细胞外ATP在肿瘤进展中可能发挥作用。P2X7受体属于配体门控离子通道受体家族,参与肿瘤的发生发展和转移。在本研究中,我们发现细胞外ATP以剂量依赖性方式刺激人T47D乳腺癌细胞的侵袭和迁移。ATP类似物BzATP可促进侵袭和迁移,而ADP则无此作用。我们进一步发现P2X7受体在T47D细胞中高表达。敲低P2X7受体后,ATP刺激的侵袭和迁移明显受到抑制。此外,ATP激活P2X7受体可下调E-钙黏蛋白的蛋白水平并上调MMP-13的产生。另外,ATP通过P2X7受体时间依赖性地诱导AKT激活,且ATP介导的侵袭和迁移需要AKT通路。综上所述,我们的结果表明,ATP激活P2X7受体可能通过激活AKT通路以及调节E-钙黏蛋白和MMP-13的表达来促进乳腺癌细胞的侵袭和迁移。因此,P2X7受体可能是治疗乳腺癌的一个有用的治疗靶点。