Transient receptor potential melastatin 7-like current in human head and neck carcinoma cells: Role in cell proliferation
Transient receptor potential melastatin 7-like current in human head and neck carcinoma cells: Role in cell proliferation
复制标题
DOI：
10.1158/0008-5472.can-07-1121
复制
发表时间：
2007-11-15
期刊：
影响因子：
11.2
通讯作者：
Xiong, Zhi-Gang
中科院分区：
文献类型：
--
作者：
Jiang, Jie;Li, Ming-Hua;Xiong, Zhi-Gang
离子通道参与正常的生理过程和各种疾病的病理过程。在本研究中，我们利用膜片钳记录、Western blotting、免疫细胞化学、小干扰RNA （siRNA）、荧光Ca2+成像和细胞计数技术，研究了瞬时受体电位美拉他汀7 （TRPM7）通道在两种常见的人头颈部鳞状细胞系FaDu和SCC25细胞生长和增殖中的存在和潜在功能。虽然在所有细胞中都记录到电压门控的K+电流，但FaDu细胞中没有表达电压门控的Na+或Ca2+电流。灌注NMDA或酸性溶液的细胞没有激活向内电流，表明缺乏NMDA受体和酸感通道。然而，降低细胞外Ca2+诱导了一个大的非脱敏电流，让人想起以前在其他细胞中描述的Ca2+感应阳离子电流或TRPM7电流。这种Ca2+感应电流可以被Gd3+， 2-氨基乙氧基二苯硼酸盐（2-APB）或细胞内Mg2+抑制，与TRPM7电流被激活一致。免疫细胞化学、Western blot和逆转录- pcr检测TRPM7蛋白和mRNA在这些细胞中的表达。用TRPM7 siRNA转染FaDu细胞可显著降低TRPM7 mRNA和蛋白的表达以及Ca2+感应电流的振幅。此外，我们发现Ca2+对FaDu细胞的生长和增殖至关重要。Gd3+和2-APB阻断TRPM7通道或siRNA抑制TRPM7表达可抑制这些细胞的生长和增殖。与FaDu细胞类似，SCC25细胞也表达trpm7样通道。抑制这些通道的功能可抑制SCC25细胞的增殖。
Ion channels are involved in normal physiologic processes and in the pathology of various diseases. In this study, we investigated the presence and potential function of transient receptor potential melastatin 7 (TRPM7) channels in the growth and proliferation of FaDu and SCC25 cells, two common human head and neck squamous carcinoma cell lines, using a combination of patch-clamp recording, Western blotting, immunocytochemistry, small interfering RNA (siRNA), fluorescent Ca2+ imaging, and cell counting techniques. Although voltage-gated K+ currents were recorded in all cells, none of FaDu cells express voltage-gated Na+ or Ca2+ currents. Perfusion of cells with NMDA or acidic solution did not activate inward currents, indicating a lack of NMDA receptor and acid-sensing channels. Lowering extracellular Ca2+, however, induced a large nondesensitizing current reminiscent of Ca2+ -sensing cation current or TRPM7 current previously described in other cells. This Ca2+ -sensing current can be inhibited by Gd3+, 2-aminoethoxydiphenyl borate (2-APB), or intracellular Mg2+, consistent with the TRPM7 current being activated. Immunocytochemistry, Western blot, and reverse transcription-PCR detected the expression of TRPM7 protein and mRNA in these cells. Transfection of FaDu cells with TRPM7 siRNA significantly reduced the expression of TRPM7 mRNA and protein as well as the amplitude of the Ca2+ -sensing current. Furthermore, we found that Ca2+ is critical for the growth and proliferation of FaDu cells. Blockade of TRPM7 channels by Gd3+ and 2-APB or suppression of TRPM7 expression by siRNA inhibited the growth and proliferation of these cells. Similar to FaDu cells, SCC25 cells also express TRPM7-like channels. Suppressing the function of these channels inhibited the proliferation of SCC25 cells.