作者感谢Thomas E. & Pamela M. Mischell Family Foundation对S.S.的支持，以及Harold C. Schott基金会对加州大学医学院Harold C. Schott捐赠主席的资助。

离子通道治疗实体瘤的药理学靶向

<ol>
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D.A.P.K. 是 Amlal Pharmaceuticals Inc. 的联合创始人、总裁兼首席执行官，S.S. 是 Amlal Pharmaceuticals Inc. 的联合创始人，也是 Bexion Pharmaceuticals， Inc. 的药物安全监测委员会成员。

离子通道功能的变化会改变细胞内信号级联，从而影响细胞的整体功能。在过去的十年中，越来越清楚的是离子通道对癌细胞的生长和转移很重要。重要的是，许多离子通道是针对各种疾病的已获批疗法的主要靶标24。研究人员已经探索了离子通道是否可能是抗癌靶点，初步结果是有希望的2,16,25。该领域刚刚...

膜转运蛋白对于细胞之间的通讯以及维持细胞稳态至关重要。在膜转运蛋白中，离子通道用于驱动细胞的生长和发育，并在具有挑战性和不断变化的环境中维持细胞的状态。据报道，离子通道还可以驱动和支持实体瘤的发展，包括全身和中枢神经系统（CNS）1,2。例如，KCa3.1通道负责调节膜电位和控制细胞体积，这在细胞周期调节中很重要。据报道，有缺陷的KCa3.1通道有助于肿瘤细胞的异常增殖3。此外，离子通道可能有助于癌症的转移性播散。例如，瞬时受体电位 （TRP） 通道参与 Ca 2+ 和 Mg2+ 内流;这种涌入激活了几种激酶和热休克蛋白，它们的作用是调节肿瘤周围的细胞外基质，这反过来又对启动癌症转移很重要4。
由于离子通道有助于癌症的发展，它们也可能是药物相关癌症治疗的靶标。例如，对治疗方式（包括化疗和新型免疫疗法）的耐药性与离子通道功能失调有关5,6,7。此外，离子通道正在成为阻碍癌症生长和发展的重要药物靶点，正在研究重新利用的小分子（FDA批准）药物以及生物聚合物，包括单克隆抗体1,2,8,9。虽然在这方面取得了很大进展，但离子通道癌症药物的发现仍然不发达。这部分是由于研究癌细胞中离子通道的独特挑战。例如，在为慢效化合物设置电生理学测定方面存在技术限制，并且在通道活化和药物作用方面存在时间差异。此外，化合物的溶解度也会阻碍进展，因为目前常用的大多数自动化电生理系统都使用疏水底物，这可能会导致化合物吸附而导致伪影。此外，使用常规电生理学测定进行筛选大型生物有机分子疗法（如天然产物、肽和单克隆抗体）在技术上具有挑战性10。最后，癌细胞的生物电特性仍然知之甚少11。
同时，离子通道的免疫荧光染色通常具有挑战性。这部分是由于它们的结构和它们在膜中的环境的复杂性，这会影响产生和使用抗体进行显微镜研究的能力。尤其重要的是，对用于染色离子通道的抗体的特异性、亲和力和重现性进行验证。应根据离子通道的商业抗体的验证策略和发表记录来考虑。实验应包括阴性对照，以证明通过敲低或敲除目标蛋白缺乏非特异性结合。或者，基于mRNA或蛋白质测定的靶蛋白不存在或丰度低的细胞系可以作为阴性对照。例如，这项研究显示了（GABA）受体亚基Gabra5在髓母细胞瘤细胞系（D283）中的定位。对具有siRNA敲低的D283细胞和另一种小脑髓母细胞瘤细胞系Daoy细胞进行Gabra5染色，并且没有明显的染色（数据未显示）。
本文介绍了分析和测定离子通道功能以及离子通道调节剂对癌细胞的影响的方法。为（1）离子通道染色细胞，（2）测试线粒体的极化状态，（3）使用电生理学建立离子通道功能以及（4）体外药物验证提供了方案。这些协议强调A型γ-氨基丁酸（GABAA）受体2,12,13,14,15,16，氯化阴离子通道和主要抑制性神经递质受体的研究。然而，这里介绍的方法适用于研究许多其他癌细胞和离子通道。

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>ABS SpectraMax Plate Reader</td>
			<td>Molecular Devices</td>
			<td>ABS</td>
			<td></td>
		</tr>
		<tr>
			<td>Accutase</td>
			<td>Invitrogen</td>
			<td>00-4555-56</td>
			<td></td>
		</tr>
		<tr>
			<td>Alexa Flor 488</td>
			<td>Invitrogen</td>
			<td>A32723</td>
			<td>Goat Anti-Rabbit</td>
		</tr>
		<tr>
			<td>Antibiotic-Antimycotic</td>
			<td>Gibco</td>
			<td>15240-062</td>
			<td>100x</td>
		</tr>
		<tr>
			<td>B27 Supplement</td>
			<td>Gibco</td>
			<td>12587-010</td>
			<td>Lacks vitamin A</td>
		</tr>
		<tr>
			<td>Biosafety Cabinet</td>
			<td>LABCONCO</td>
			<td>302381101</td>
			<td>Class II, Type A2</td>
		</tr>
		<tr>
			<td>Bovine Serum Albumin</td>
			<td>Fisher Scientific</td>
			<td>BP1606-100</td>
			<td></td>
		</tr>
		<tr>
			<td>CO2 Incubator</td>
			<td>Fisher Scientific</td>
			<td>13-998-211</td>
			<td>Heracell VIOS 160i</td>
		</tr>
		<tr>
			<td>Calcium Chloride</td>
			<td>Fisher Scientific</td>
			<td>C7902</td>
			<td>Dihydrate</td>
		</tr>
		<tr>
			<td>Cell Culture Dishes, 150 mm</td>
			<td>Fisher Scientific</td>
			<td>12-600-004</td>
			<td>Cell culture treated</td>
		</tr>
		<tr>
			<td>Cell Culture Flasks, 75 cm2</td>
			<td>Fisher Scientific</td>
			<td>430641U</td>
			<td>Cell culture treated</td>
		</tr>
		<tr>
			<td>Cell Culture Plates, 6 well</td>
			<td>Fisher Scientific</td>
			<td>353046</td>
			<td>Cell culture treated</td>
		</tr>
		<tr>
			<td>Cell Culture Plates, 96 well</td>
			<td>Fisher Scientific</td>
			<td>353072</td>
			<td>Cell culture treated</td>
		</tr>
		<tr>
			<td>Centrifuge</td>
			<td>Eppendorf</td>
			<td>EP-5804R</td>
			<td>Refrigerated</td>
		</tr>
		<tr>
			<td>Corning CoolCell</td>
			<td>Fisher Scientific</td>
			<td>07-210-0006</td>
			<td></td>
		</tr>
		<tr>
			<td>Coverslips, 22 x 22 mm</td>
			<td>Fisher Scientific</td>
			<td>12-553-450</td>
			<td>Corning brand</td>
		</tr>
		<tr>
			<td>D283 Med</td>
			<td>ATCC</td>
			<td>HTB-185</td>
			<td></td>
		</tr>
		<tr>
			<td>DABCO Mounting Media</td>
			<td>EMS</td>
			<td>17989-97</td>
			<td></td>
		</tr>
		<tr>
			<td>D-Glucose</td>
			<td>Sigma Life Sciences</td>
			<td>D9434</td>
			<td></td>
		</tr>
		<tr>
			<td>Dimethyl Sulfoxide</td>
			<td>Sigma Aldrich</td>
			<td>D2650</td>
			<td>Cell culture grade</td>
		</tr>
		<tr>
			<td>DMEM/F12, base media</td>
			<td>Fisher Scientific</td>
			<td>11330-032</td>
			<td>With phenol red</td>
		</tr>
		<tr>
			<td>DMEM/F12, phenol red free</td>
			<td>Fisher Scientific</td>
			<td>21041-025</td>
			<td></td>
		</tr>
		<tr>
			<td>EGTA</td>
			<td>Sigma Aldrich</td>
			<td>E4378</td>
			<td></td>
		</tr>
		<tr>
			<td>Epidermal Growth Factor</td>
			<td>STEMCELL</td>
			<td>78006.1</td>
			<td></td>
		</tr>
		<tr>
			<td>FCCP</td>
			<td>Abcam</td>
			<td>AB120081</td>
			<td></td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum, Qualified</td>
			<td>Gibco</td>
			<td>10437-028</td>
			<td></td>
		</tr>
		<tr>
			<td>Fibroblast Growth Factor, Basic</td>
			<td>Millipore</td>
			<td>GF003</td>
			<td></td>
		</tr>
		<tr>
			<td>GARBA5 Antibody</td>
			<td>Aviva</td>
			<td>ARP30687_P050</td>
			<td>Rabbit Polyclonal</td>
		</tr>
		<tr>
			<td>Glutamax</td>
			<td>Gibco</td>
			<td>35050-061</td>
			<td></td>
		</tr>
		<tr>
			<td>Glycerol Mounting Medium</td>
			<td>EMS</td>
			<td>17989-60</td>
			<td>With DAPI+DABCO</td>
		</tr>
		<tr>
			<td>Hemocytometer</td>
			<td>Millipore Sigma</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Heparin</td>
			<td>STEMCELL</td>
			<td>7980</td>
			<td></td>
		</tr>
		<tr>
			<td>HEPES</td>
			<td>HyClone</td>
			<td>SH3023701</td>
			<td>Solution</td>
		</tr>
		<tr>
			<td>HEPES</td>
			<td>Fisher Scientific</td>
			<td>BP310-500</td>
			<td>Solid</td>
		</tr>
		<tr>
			<td>ImageJ</td>
			<td>Open platform</td>
			<td></td>
			<td>With Fiji plugins</td>
		</tr>
		<tr>
			<td>Immuno Mount DAPI</td>
			<td>EMS</td>
			<td>17989-97</td>
			<td></td>
		</tr>
		<tr>
			<td>KRM-II-08</td>
			<td></td>
			<td></td>
			<td>experimental compounds not available from a commercial source</td>
		</tr>
		<tr>
			<td>Leica Application Suite X</td>
			<td>Leica Microsystems</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Leukemia Inhibitory Factor</td>
			<td>Novus</td>
			<td>N276314100U</td>
			<td></td>
		</tr>
		<tr>
			<td>L-Glutamine</td>
			<td>Gibco</td>
			<td>25030-081</td>
			<td></td>
		</tr>
		<tr>
			<td>Magnesium Chloride</td>
			<td>Sigma Aldrich</td>
			<td>M9272</td>
			<td>Hexahydrate</td>
		</tr>
		<tr>
			<td>Microscope, Confocal</td>
			<td>Leica</td>
			<td>SP8</td>
			<td></td>
		</tr>
		<tr>
			<td>Microscope, Light</td>
			<td>VWR</td>
			<td>76382-982</td>
			<td>DMiL Inverted</td>
		</tr>
		<tr>
			<td>MTS - Promega One Step</td>
			<td>Promega</td>
			<td>G3581</td>
			<td></td>
		</tr>
		<tr>
			<td>Multi-channel pipette, 0.5-10 &#181;L</td>
			<td>Eppendorf</td>
			<td>Z683914</td>
			<td></td>
		</tr>
		<tr>
			<td>Multi-channel pipette, 10-100 &#181;L</td>
			<td>Eppendorf</td>
			<td>Z683930</td>
			<td></td>
		</tr>
		<tr>
			<td>Multi-channel pipette, 30-300 &#181;L</td>
			<td>Eppendorf</td>
			<td>Z683957</td>
			<td></td>
		</tr>
		<tr>
			<td>Nest-O-Patch</td>
			<td>Heka</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Neurobasal-A Medium</td>
			<td>Gibco</td>
			<td>10888022</td>
			<td>Without vitamin A</td>
		</tr>
		<tr>
			<td>Neurobasal-A Medium</td>
			<td>Gibco</td>
			<td>12348-017</td>
			<td>Phenol red free</td>
		</tr>
		<tr>
			<td>Non-Essential Amino Acids</td>
			<td>Gibco</td>
			<td>11140-050</td>
			<td></td>
		</tr>
		<tr>
			<td>NOR-QH-II-66</td>
			<td></td>
			<td></td>
			<td>experimental compounds not available from a commercial source</td>
		</tr>
		<tr>
			<td>Parafilm</td>
			<td>Fisher Scientific</td>
			<td>50-998-944</td>
			<td>4 inch width</td>
		</tr>
		<tr>
			<td>Paraformaldehyde</td>
			<td>EMS</td>
			<td>RT-15710</td>
			<td></td>
		</tr>
		<tr>
			<td>PATHCHMASTER</td>
			<td>Heka</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Penicillin-Streptomycin</td>
			<td>Gibco</td>
			<td>15140-122</td>
			<td></td>
		</tr>
		<tr>
			<td>Perfusion System</td>
			<td>Nanion</td>
			<td>4000120</td>
			<td></td>
		</tr>
		<tr>
			<td>PFA</td>
			<td>EMS</td>
			<td>RT-15710</td>
			<td></td>
		</tr>
		<tr>
			<td>Phosphate Bufered Saline</td>
			<td>Fisher Scientific</td>
			<td>AAJ75889K2</td>
			<td>Reagent grade</td>
		</tr>
		<tr>
			<td>Poly-D-Lysine</td>
			<td>Fisher Scientific</td>
			<td>A3890401</td>
			<td></td>
		</tr>
		<tr>
			<td>Poly-L-Lysine</td>
			<td>Sigma Life Sciences</td>
			<td>P4707</td>
			<td></td>
		</tr>
		<tr>
			<td>Port-a-Patch</td>
			<td>Nanion</td>
			<td>21000072</td>
			<td></td>
		</tr>
		<tr>
			<td>Potassium Chloride</td>
			<td>Sigma Life Sciences</td>
			<td>P5405</td>
			<td></td>
		</tr>
		<tr>
			<td>Primary Antibody</td>
			<td>Invitrogen</td>
			<td>MA5-34653</td>
			<td>Rabbit Monoclonal</td>
		</tr>
		<tr>
			<td>Prism</td>
			<td>GraphPad</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Propofol</td>
			<td>Fisher Scientific</td>
			<td>NC0758676</td>
			<td>1 mL ampule</td>
		</tr>
		<tr>
			<td>QH-II-66</td>
			<td></td>
			<td></td>
			<td>experimental compounds not available from a commercial source</td>
		</tr>
		<tr>
			<td>Reagent Reservoirs</td>
			<td>VWR</td>
			<td>89094-664</td>
			<td>Sterile</td>
		</tr>
		<tr>
			<td>Slides, 75 x 25 mm</td>
			<td>Fisher Scientific</td>
			<td>12-544-7</td>
			<td>Frosted one side</td>
		</tr>
		<tr>
			<td>Sodium Bicarbonate</td>
			<td>Corning</td>
			<td>25-035-Cl</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium Chloride</td>
			<td>Fisher Scientific</td>
			<td>S271-3</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium Pyruvate</td>
			<td>Gibco</td>
			<td>11360-070</td>
			<td></td>
		</tr>
		<tr>
			<td>Synth-a-Freeze Medium</td>
			<td>Gibco</td>
			<td>R00550</td>
			<td>Cryopreservation</td>
		</tr>
		<tr>
			<td>TMRE</td>
			<td>Fisher Scientific</td>
			<td>50-196-4741</td>
			<td>Reagent</td>
		</tr>
		<tr>
			<td>TMRE Kit</td>
			<td>Abcam</td>
			<td>AB113852</td>
			<td>Kit</td>
		</tr>
		<tr>
			<td>Triton X-100</td>
			<td>Sigma Aldrich</td>
			<td>NC0704309</td>
			<td></td>
		</tr>
		<tr>
			<td>Trypan Blue</td>
			<td>Gibco</td>
			<td>15-250-061</td>
			<td>Solution, 0.4%</td>
		</tr>
		<tr>
			<td>Trypsin/EDTA</td>
			<td>Gibco</td>
			<td>25200-072</td>
			<td>Solution, 0.25%</td>
		</tr>
		<tr>
			<td>Vortex Mixer</td>
			<td>VWR</td>
			<td>97043-562</td>
			<td></td>
		</tr>
		<tr>
			<td>Whatman Filter Paper</td>
			<td>Fisher Scientific</td>
			<td>09-927-841</td>
			<td></td>
		</tr>
	</tbody>
</table>

screening ion channels in cancer cells

离子通道对于细胞发育和维持细胞稳态至关重要。离子通道功能的扰动有助于各种疾病或离子通道病的发展。癌细胞利用离子通道来驱动自身的发育，以及作为肿瘤的改善，并在包括各种非癌细胞的微环境中同化。此外，肿瘤微环境中生长因子和激素水平的增加可导致离子通道表达增强，从而有助于癌细胞增殖和存活。因此，离子通道的药理学靶向是治疗实体恶性肿瘤（包括原发性和转移性脑癌）的潜在有前途的方法。本文描述了表征癌细胞中离子通道功能的协议以及分析离子通道调节剂以确定其对癌症活力的影响的方法。这些包括对细胞进行离子通道染色，测试线粒体的极化状态，使用电生理学建立离子通道功能，以及进行活力测定以评估药物效力。

Membrane transport proteins are critical for communication between cells, as well as for maintaining cellular homeostasis. Amongst the membrane transport proteins, ion channels serve to drive the growth and development of cells and to maintain the state of cells in challenging and changing environments. Ion channels have also been reported to drive and support the development of solid tumors, both systemically and in the central nervous system (CNS)1,2. For example, KCa3.1 channels are responsible for regulating membrane potential and controlling cell volume, which is important in cell-cycle regulation. Defective KCa3.1 channels have been reported to contribute to the abnormal proliferation of tumor cells3. Further, ion channels may contribute to the metastatic dissemination of cancers. Transient receptor potential (TRP) channels, for example, are involved in Ca2+ and Mg2+ influx; this influx activates several kinases and heat shock proteins that function to regulate the extracellular matrix surrounding a tumor, which is, in turn, important for initiating cancer metastasis4.
Since ion channels can contribute to the development of cancers, they may also be targets for drug-related cancer treatment. For example, resistance to treatment modalities, including chemotherapy and novel immunotherapy, is related to ion channel function dysregulation5,6,7. In addition, ion channels are emerging as important drug targets to impede the growth and development of cancers, with repurposed small molecule (FDA-approved) drugs being examined, as well as biopolymers, including monoclonal antibodies1,2,8,9. While there has been much progress on this front, ion channel cancer drug discovery remains underdeveloped. This is partly due to the unique challenges of studying ion channels in cancer cells. For example, there are technical limitations in setting up electrophysiology assays for slow-acting compounds and temporal differences in channel activation and drug action. Further, the solubility of compounds can also impede progress, as most of the automated electrophysiology systems commonly in use today utilize hydrophobic substrates, which may contribute to artifacts as a result of compound adsorption. In addition, large bioorganic molecular therapeutics such as natural products, peptides, and monoclonal antibodies are technically challenging to screen using conventional electrophysiology assays10. Finally, the bioelectrical properties of cancer cells remain poorly understood11.
Meanwhile, the immunofluorescence staining of ion channels is often challenging. This is due, in part, to the complexity of their structures and their context in the membrane, which impact the ability to both generate and employ antibodies for microscopy studies. It is especially important that the antibodies used to stain ion channels are validated for specificity, affinity, and reproducibility. Commercial antibodies for ion channels should be considered based on their validation strategy and publication record. Experiments should include negative controls to demonstrate the lack of nonspecific binding by either knockdown or knockout of the target protein. Alternatively, cell lines in which the target protein is absent or in low abundance based on mRNA or protein determinations may serve as negative controls. For example, this study shows the localization of the (GABA) receptor&#160;subunit Gabra5 in a medulloblastoma cell line (D283). D283 cells with an siRNA knockdown and Daoy&#160;cells, another cerebellar medulloblastoma cell line, were stained for Gabra5 and showed no appreciatable staining (data not shown).
Here, methods are presented to analyze and assay ion channel function, as well as the effect of ion channel modulators on cancer cells. Protocols are provided for (1) staining cells for an ion channel, (2) testing the polarized state of mitochondria, (3) establishing ion channel function using electrophysiology, and (4) in vitro drug validation. These protocols emphasize studies of the type A gamma-aminobutyric acid (GABAA) receptor2,12,13,14,15,16, a chloride anion channel and major inhibitory neurotransmitter receptor. However, the methods presented here apply to studying many other cancer cells and ion channels.

作者聚焦：探索离子通道在癌症中的作用：表征和可能的治疗方法 

筛选癌细胞中的离子通道

The function of ion channels is crucial in cell biology and significantly impacts cancer growth. Our team is focused on targeting ion channels to aid cancer treatments. The field has recently gained a greater understanding of the tumor microenvironment and how cancer cells take hold in healthy tissue, highlighting the importance of ion channels in cancer.One of the biggest challenges in current experiment is the availability of immune-competent animal model that can effectively test therapeutic treatments. We have established that GABA A receptor is a therapeutic vulnerability to disparate cancers and identified a new class of GABA A receptor activators that effectively impair cancer cells. Ion channels play a crucial role in regulating cancer cell behavior, and they hold great potential as target for cancer treatment.Our research has highlighted how an established class of drug can be employed to treat cancer effectively.

以上是可用于表征癌细胞中离子通道的选择程序。第一个方案突出显示离子通道的染色。如前所述，在染色离子通道或就此而言，染色细胞外膜中存在的任何蛋白质时存在许多挑战。图1所示是五聚体GABAA受体亚基的染色。第二个协议强调了测试癌细胞中线粒体极化状态的结果。线粒体对细胞活力和增殖以及细胞死亡起着至关重要的作用。在哺乳动物细胞中，线粒体?...

Watch this Scientific Journal Video about Exploring the Role of Ion Channels in Cancer: Characterization and Potential Treatment Approaches at JoVE.com

离子通道的药理学靶向是治疗实体瘤的一种有前途的方法。提供了详细的方案，用于表征癌细胞中的离子通道功能并分析离子通道调节剂对癌症活力的影响。

Ion channels are critical for cell development and maintaining cell homeostasis. The perturbation of ion channel function contributes to the development ...

离子通道的功能在细胞生物学中至关重要，并显着影响癌症的生长。我们的团队专注于靶向离子通道以帮助癌症治疗。该领域最近对肿瘤微环境以及癌细胞如何在健康组织中扎根有了更深入的了解，突出了离子通道在癌症中的重要性。当前实验中最大的挑战之一是免疫能力动物模型的可用性，可以有效地测试治疗。我们已经确定GABA A受体是不同癌症的治疗脆弱性，并确定了一类有效损害癌细胞的新型GABA A受体激活剂。离子通道在调节癌细胞行为中起着至关重要的作用，它们作为癌症治疗的靶标具有巨大的潜力。我们的研究强调了如何利用一类既定的药物来有效治疗癌症。

Research

JoVE Journal

Cancer Research

Screening Ion Channels in Cancer Cells

1.4K 次观看.  University of Cincinnati College of Medicine. 离子通道的功能在细胞生物学中至关重要，并显着影响癌症的生长。我们的团队专注于靶向离子通道以帮助癌症治疗。该领域最近对肿瘤微环境以及癌细胞如何在健康组织中扎根有了更深入的了解，突出了离子通道在癌症中的重要性。当前实验中最大的挑战之一是免疫能力动物模型的可用性，可以有效地测试治疗。我们已经确定GABA A受体是不同癌症的治疗脆弱性，并确?...

视频: 作者聚焦：探索离子通道在癌症中的作用：表征和可能的治疗方法 

Ion channels are critical for cell development and maintaining cell homeostasis. The perturbation of ion channel function contributes to the development of a broad range of disorders or channelopathies. Cancer cells utilize ion channels to drive their own development, as well as to improve as a tumor and to assimilate in a microenvironment that includes various non-cancerous cells. Furthermore, increases in levels of growth factors and hormones within the tumor microenvironment can result in enhanced ion channel expression, which contributes to cancer cell proliferation and survival. Thus, the pharmacological targeting of ion channels is potentially a promising approach to treating solid malignancies, including primary and metastatic brain cancers. Herein, protocols to characterize the function of ion channels in cancerous cells and approaches to analyze modulators of ion channels to determine their impact on cancer viability are described. These include staining a cell(s) for an ion channel(s), testing the polarized state of mitochondria, establishing ion channel function using electrophysiology, and performing viability assays to assess drug potency.

The pharmacological targeting of ion channels is a promising approach to treating solid tumors. Detailed protocols are provided for characterizing ion channel function in cancer cells and assaying the effects of ion channel modulators on cancer viability.

科研

癌症研究

Testing the Polarized State of Mitochondria to Analyze the Ion Channel Function in Cancer Cells 

To begin, maintain cells in a 75-square-centimeter culture flask. Aspirate the culture medium and rinse the cells with PBS without calcium and magnesium. Next, add two milliliters of 0.25%trypsin EDTA to detach adherence cells.Incubate for five minutes at room temperature and resuspend the cells in 10 milliliters of medium. Next, collect the cells from the flask into a 15-milliliter centrifuge tube. Centrifuge at 480 G for five minutes at room temperature and aspirate the medium.Resuspend the cells in 5 to 10 milliliters of medium based on the original confluency of the culture. Remove 100 microliters of cells and add to a 1.5-milliliter tube with 100 microliters of 0.4%trypan blue. Add the cells to the hemocytometer, and count them by observing under the microscope and using the manual tally counter.Dilute the cells to three times 10 to the fourth cells per milliliter in the culture medium without phenol red. Add 2.5 milliliters of the cell suspension to each well of a six-well plate with poly-D-lysine-coated cover slip per the manufacturer's directions. Grow the cells overnight at 37 degrees Celsius and 5%carbon dioxide in a humidified incubator to enable cell attachment to the cover slip.The next day, examine cell attachment under an inverted microscope using a 20X objective. Prepare the treatment stock solutions at the desired concentrations and create a media-only control, a vehicle-only control at a concentration that matches the test compound, and a control with the ionophore FCCP and the test compounds. Working with one cover slip at a time, add 1.8 milliliters of medium for the condition under the study to the cells.Incubate the cells treated with either the control or test compound at 37 degrees Celsius and 5%carbon dioxide in a humidified environment for the desired time. Following the treatment period, add 200 microliters of 10X TMRE to the cells. Incubate for 15 to 30 minutes at 37 degrees Celsius in a 5%carbon dioxide humidified environment.Gently aspirate the medium and rinse the cells two times with PBS to minimize background interference. Then invert the cover slip onto a microscope slide labeled with the treatment conditions. Image the cells live at 549 nanometers excitation and 575 nanometers emission.Utilize a confocal microscope to capture several Z-stack fields with high-speed image capture before the cell integrity is lost. Save and store the image file for later analysis. The cells with active mitochondria retained TMRE staining and showed high fluorescence.Depolarized or inactive mitochondria have reduced membrane potential, fail to retain TMRE, and show a low fluorescence signal.

测试线粒体的极化状态以分析癌细胞中的离子通道功能 

In Vitro Drug Validation to Assay Ion Channel Function in Cancer Cells

To begin, plate the cells in 75 microliters per well of antibiotic-free medium without HEPES buffer to determine the IC50. On the second day, prepare the control solution and the test solutions by performing serial dilutions of high-concentration stock solutions. After adding control and test solutions to the cells, incubate the cells at 37 degrees Celsius and 5%carbon dioxide in a humidified environment for 48 hours.Begin the cell proliferation assay by first vortexing the MTS reagent to fully dissolve any precipitated reagent before usage on day three of the experiment transfer the thawed MTS reagents into a sterile, 25-milliliter reagent reservoir. Pipette 20 microliters of MTS reagent into each well of the 96-well plate containing samples and 100 microliters of culture medium. Incubate the plate at 37 degrees Celsius and 5%carbon dioxide in a humidified environment for one to four hours.Then, centrifuge the plate at room temperature to remove any bubbles that may interfere with the absorbance reading. Measure the absorbance at 490 nanometers with a microplate reader or spectrophotometer. A 96-well plate showing the calorimetric results of an MTS assay with increasing drug concentrations is presented.The dose response curve showed that the test agent impairs the viability of the cancer cells in a dose-dependent manner.