Name: live imaging to study microtubule dynamic instability in taxane-resistant breast cancers
Uploaded: 2017-02-20T13:00:00
Description: Watch this Scientific Journal Video about Live Imaging to Study Microtubule Dynamic Instability in Taxane-resistant Breast Cancers at JoVE.com

This research is supported by funding from CBCF (to ZW).

1. Preparing the Cells for Live Imaging
<ol>
	<li>Cell culture and seeding
	<ol>
		<li>Use MCF-7 breast cancer cells selected for resistance to docetaxel (MCF-7TXT) and their non-resistant parental cell line (MCF-7CC). The detailed selection process and the characterization of these selected cell lines were described previously24.</li>
		<li>Grow all cells in 10 cm culture dishes at 37 &#176;C in a medium composed 90% of Dulbecco&#39;s modified Eagle&#39;s ...

<ol>
	<li>Kamangar, F., Dores, G. M., Anderson, W. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Patterns+of+cancer+incidence,+mortality,+and+prevalence+across+five+continents:+defining+priorities+to+reduce+cancer+disparities+in+different+geographic+regions+of+the+world.">Patterns of cancer incidence, mortality, and prevalence across five continents: defining priorities to reduce cancer disparities in different geographic regions of the world.</a> J Clin Oncol. 24 (14), 2137-2150 (2006).</li><li>Yardley, D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Drug+resistance+and+the+role+of+combination+chemotherapy+in+improving+patient+outcomes.">Drug resistance and the role of combination chemotherapy in improving patient outcomes.</a> Int J Breast Cancer. 2013, 137414 (2013).</li><li>Jassem, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Doxorubicin+and+paclitaxel+versus+fluorouracil,+doxorubicin,+and+cyclophosphamide+as+first-line+therapy+for+women+with+metastatic+breast+cancer:+final+results+of+a+randomized+phase+III+multicenter+trial.">Doxorubicin and paclitaxel versus fluorouracil, doxorubicin, and cyclophosphamide as first-line therapy for women with metastatic breast cancer: final results of a randomized phase III multicenter trial.</a> J Clin Oncol. 19 (6), 1707-1715 (2001).</li><li>Nabholtz, J. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Docetaxel+and+doxorubicin+compared+with+doxorubicin+and+cyclophosphamide+as+first-line+chemotherapy+for+metastatic+breast+cancer:+results+of+a+randomized,+multicenter,+phase+III+trial.">Docetaxel and doxorubicin compared with doxorubicin and cyclophosphamide as first-line chemotherapy for metastatic breast cancer: results of a randomized, multicenter, phase III trial.</a> J Clin Oncol. 21 (6), 968-975 (2003).</li><li>Zelnak, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Overcoming+taxane+and+anthracycline+resistance.">Overcoming taxane and anthracycline resistance.</a> Breast J. 16 (3), 309-312 (2010).</li><li>Rivera, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Implications+of+anthracycline-resistant+and+taxane-resistant+metastatic+breast+cancer+and+new+therapeutic+options.">Implications of anthracycline-resistant and taxane-resistant metastatic breast cancer and new therapeutic options.</a> Breast J. 16 (3), 252-263 (2010).</li><li>Longley, D. B., Johnston, P. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Molecular+mechanisms+of+drug+resistance.">Molecular mechanisms of drug resistance.</a> J Pathol. 205 (2), 275-292 (2005).</li><li>Downing, K. H., Nogales, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Crystallographic+structure+of+tubulin:+implications+for+dynamics+and+drug+binding.">Crystallographic structure of tubulin: implications for dynamics and drug binding.</a> Cell Struct.Funct. 24 (5), 269-275 (1999).</li><li>McGrogan, B. T., Gilmartin, B., Carney, D. N., McCann, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Taxanes,+microtubules+and+chemoresistant+breast+cancer.">Taxanes, microtubules and chemoresistant breast cancer.</a> Biochim.Biophys.Acta. 1785 (2), 96-132 (2008).</li><li>Kamath, K., Oroudjev, E., Jordan, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determination+of+microtubule+dynamic+instability+in+living+cells.">Determination of microtubule dynamic instability in living cells.</a> Methods Cell Biol. 97, 1-14 (2010).</li><li>Dumontet, C., Jordan, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microtubule-binding+agents:+a+dynamic+field+of+cancer+therapeutics.">Microtubule-binding agents: a dynamic field of cancer therapeutics.</a> Nat Rev Drug Discov. 9 (10), 790-803 (2010).</li><li>Jordan, M. A., Wilson, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microtubules+as+a+target+for+anticancer+drugs.">Microtubules as a target for anticancer drugs.</a> Nat.Rev.Cancer. 4 (4), 253-265 (2004).</li><li>Gascoigne, K. E., Taylor, S. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=How+do+anti-mitotic+drugs+kill+cancer+cells?.">How do anti-mitotic drugs kill cancer cells?.</a> J.Cell Sci. 122 (15), 2579-2585 (2009).</li><li>Kavallaris, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microtubules+and+resistance+to+tubulin-binding+agents.">Microtubules and resistance to tubulin-binding agents.</a> Nat.Rev.Cancer. 10 (3), 194-204 (2010).</li><li>Diaz, J. F., Valpuesta, J. M., Chacon, P., Diakun, G., Andreu, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Changes+in+microtubule+protofilament+number+induced+by+Taxol+binding+to+an+easily+accessible+site.+Internal+microtubule+dynamics.">Changes in microtubule protofilament number induced by Taxol binding to an easily accessible site. Internal microtubule dynamics.</a> J.Biol.Chem. 273 (50), 33803-33810 (1998).</li><li>Abal, M., Andreu, J. M., Barasoain, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Taxanes:+microtubule+and+centrosome+targets,+and+cell+cycle+dependent+mechanisms+of+action.">Taxanes: microtubule and centrosome targets, and cell cycle dependent mechanisms of action.</a> Curr Cancer Drug Targets. 3 (3), 193-203 (2003).</li><li>Wang, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Multiple+mechanisms+underlying+acquired+resistance+to+taxanes+in+selected+docetaxel-resistant+MCF-7+breast+cancer+cells.">Multiple mechanisms underlying acquired resistance to taxanes in selected docetaxel-resistant MCF-7 breast cancer cells.</a> BMC Cancer. 14 (37), (2014).</li><li>Lal, S., Mahajan, A., Chen, W. N., Chowbay, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pharmacogenetics+of+target+genes+across+doxorubicin+disposition+pathway:+a+review.">Pharmacogenetics of target genes across doxorubicin disposition pathway: a review.</a> Curr. Drug Metab. 11 (1), 115-128 (2010).</li><li>Murray, S., Briasoulis, E., Linardou, H., Bafaloukos, D., Papadimitriou, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Taxane+resistance+in+breast+cancer:+mechanisms,+predictive+biomarkers+and+circumvention+strategies.">Taxane resistance in breast cancer: mechanisms, predictive biomarkers and circumvention strategies.</a> Cancer Treat.Rev. 38 (7), 890-903 (2012).</li><li>Kamath, K., Wilson, L., Cabral, F., Jordan, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=BetaIII-tubulin+induces+paclitaxel+resistance+in+association+with+reduced+effects+on+microtubule+dynamic+instability.">BetaIII-tubulin induces paclitaxel resistance in association with reduced effects on microtubule dynamic instability.</a> J.Biol.Chem. 280 (13), 12902-12907 (2005).</li><li>Banerjee, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Increased+levels+of+tyrosinated+alpha-,+beta(III)-,+and+beta(IV)-tubulin+isotypes+in+paclitaxel-resistant+MCF-7+breast+cancer+cells.">Increased levels of tyrosinated alpha-, beta(III)-, and beta(IV)-tubulin isotypes in paclitaxel-resistant MCF-7 breast cancer cells.</a> Biochem.Biophys.Res.Commun. 293 (1), 598-601 (2002).</li><li>Wiesen, K. M., Xia, S., Yang, C. P., Horwitz, S. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Wild-type+class+I+beta-tubulin+sensitizes+Taxol-resistant+breast+adenocarcinoma+cells+harboring+a+beta-tubulin+mutation.">Wild-type class I beta-tubulin sensitizes Taxol-resistant breast adenocarcinoma cells harboring a beta-tubulin mutation.</a> Cancer Lett. 257 (2), 227-235 (2007).</li><li>Iseri, O. D., Kars, M. D., Arpaci, F., Gunduz, U. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gene+expression+analysis+of+drug-resistant+MCF-7+cells:+implications+for+relation+to+extracellular+matrix+proteins.">Gene expression analysis of drug-resistant MCF-7 cells: implications for relation to extracellular matrix proteins.</a> Cancer Chemother.Pharmacol. 65 (3), 447-455 (2010).</li><li>Hembruff, S. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Role+of+drug+transporters+and+drug+accumulation+in+the+temporal+acquisition+of+drug+resistance.">Role of drug transporters and drug accumulation in the temporal acquisition of drug resistance.</a> BMC.Cancer. 8, 318 (2008).</li><li>Yenjerla, M., Lopus, M., Wilson, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Analysis+of+dynamic+instability+of+steady-state+microtubules+in+vitro+by+video-enhanced+differential+interference+contrast+microscopy+with+an+appendix+by+Emin+Oroudjev.">Analysis of dynamic instability of steady-state microtubules in vitro by video-enhanced differential interference contrast microscopy with an appendix by Emin Oroudjev.</a> Methods Cell Biol. 95, 189-206 (2010).</li><li>Sammak, P. J., Gorbsky, G. J., Borisy, G. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microtubule+dynamics+in+vivo:+a+test+of+mechanisms+of+turnover.">Microtubule dynamics in vivo: a test of mechanisms of turnover.</a> J Cell Biol. 104 (3), 395-405 (1987).</li><li>Walker, R. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dynamic+instability+of+individual+microtubules+analyzed+by+video+light+microscopy:+rate+constants+and+transition+frequencies.">Dynamic instability of individual microtubules analyzed by video light microscopy: rate constants and transition frequencies.</a> J Cell Biol. 107 (4), 1437-1448 (1988).</li><li>Desai, A., Mitchison, T. 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There are two major methods to measure microtubule dynamic instability: in vitro and in vivo. In the in vitro method, purified tubulin is used to measure microtubule dynamic instability with computer-enhanced time-lapse differential interference-contrast microscopy. In the in vivo method, microinjected fluorescent tubulin, or expressed GFP-tubulin, is incorporated into microtubules. The dynamics (growth and shortening) of the microtubules is then recorded by time-lapse using a sensitiv...

The leading cause of breast cancer mortality is through metastasis1,2. Taxanes, such as docetaxel and paclitaxel, are currently used as first-line regimens in the treatment of metastatic breast cancer2,3,4,5,6. They are part of a group of microtubule-targeting agents (MTAs) that disrupt microtubule dynamics. However, one of the greatest challenges to using taxanes in curative therapy is the development of taxane resistance in cancer cells, which leads to disease recurrence7. Drug resistance accounts for more than 90% of all deaths among patients with metastatic breast cancer7.
Microtubules are formed by the polymerization of &#945;- and &#946;-tubulin heterodimers8,9. The precise regulation of microtubule dynamics is important for many cellular functions, including cell polarization, cell cycle progression, intracellular transport, and cell signaling. Dysregulation of microtubules and their dynamics will disrupt cell function and result in cell death10,11. Depending on how they cause this dysregulation, MTA drugs can be classified as either microtubule stabilizing agents (i.e., taxanes) or microtubule-destabalizing agents (i.e., vinca alkaloids or colchicine-site binding agents)20. Despite their opposite effects on microtubule mass, at a sufficient dosage, both classes can kill cancer cells through their effects on microtubule dynamics21.
Taxanes function primarily by stabilizing the microtubule spindle12, leading to chromosomal misalignment. The subsequent perpetual activation of the spindle assembly checkpoint (SAC) arrests the cell in mitosis. Prolonged mitotic arrest then causes apoptosis13,14. Taxane interacts with microtubules through the taxane binding site on &#946;-tubulin8,15, which is only present in assembled tubulin16.
Multiple mechanisms for taxane resistance have been proposed9,17. These mechanisms include both general multidrug resistance due to the overexpression of drug-efflux proteins and taxane-specific resistance5,9,18,19. For example, taxane-resistant cancer cells may have altered expression and function of certain &#946;-tubulin isotypes5,9,19,20,21,22,23. By using an in vivo method to measure microtubule dynamic instability, we show that, when compared to non-resistant, parental MCF-7CC cells17, the microtubule dynamics of docetaxel-resistant MCF-7TXT cells are insensitive to docetaxel treatment.
To better understand the function of MTAs and the exact mechanism of taxane-resistance in cancerous cells, it is essential to measure microtubule dynamics. Here, we report an in vivo method of doing so. By using live imaging in combination with the expression of GFP-tagged tubulin in cells, we can measure the microtubule dynamics of MCF-7TXT and MCF-7CC cells with and without docetaxel treatment. The results can help us design more effective drugs that can overcome taxane resistance.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Dulbecco&#39;s Modified Eagle&#39;s Medium (DMEM)</td>
			<td>Sigma-Aldrich</td>
			<td>D5796</td>
			<td></td>
		</tr>
		<tr>
			<td>Non-essential amino acids</td>
			<td>Life Technologies, Invitrogen</td>
			<td>11140-050</td>
			<td></td>
		</tr>
		<tr>
			<td>FBS</td>
			<td>Gibco, Invitrogen</td>
			<td>12483</td>
			<td></td>
		</tr>
		<tr>
			<td>Anti-Anti (100x)</td>
			<td>Life Technologies, Invitrogen</td>
			<td>15240-062</td>
			<td></td>
		</tr>
		<tr>
			<td>docetaxel</td>
			<td>Sigma-Aldrich</td>
			<td>01885-5mg-F</td>
			<td></td>
		</tr>
		<tr>
			<td>DMEM phenol red-free</td>
			<td>Gibco, Invitrogen</td>
			<td>21063</td>
			<td></td>
		</tr>
		<tr>
			<td>CellLight Reagent *BacMam 2.0* GFP-tubulin</td>
			<td>ThermoFisher Scientific</td>
			<td>C10613</td>
			<td>Key reagent for expressing GFP tubulin in cells</td>
		</tr>
		<tr>
			<td>CellLight Reagent *BacMam 2.0* GFP</td>
			<td>ThermoFisher Scientific</td>
			<td>B10383</td>
			<td>Control</td>
		</tr>
		<tr>
			<td>Dimethyl Sulfoxide (DMSO)</td>
			<td>Sigma-Aldrich+B9:AA9</td>
			<td>472301</td>
			<td>for dissoving decetaxel</td>
		</tr>
		<tr>
			<td>22-mm glass coveslip</td>
			<td>Fisher Scientifics</td>
			<td>12-545-101</td>
			<td></td>
		</tr>
		<tr>
			<td>6-well culture plate</td>
			<td>Greiner Bio-One International</td>
			<td>6 Well Celi Culture Plate</td>
			<td></td>
		</tr>
		<tr>
			<td>DeltaVision Microscopy Imaging Systems</td>
			<td>GE Health</td>
			<td></td>
			<td>This system is equipped with weather station for controlling temperature and CO2. It also equipped with Worx Software for deconvolution and time lapse control.</td>
		</tr>
		<tr>
			<td>Trypsin-EDTA (0.25%), phenol red</td>
			<td>ThermoFisher Scientific</td>
			<td>25200056</td>
			<td></td>
		</tr>
		<tr>
			<td>Bright-Line Hemacytometer Set, Hausser Scientific</td>
			<td>Hausser Scientific, Distributed by VWR</td>
			<td>Supplier No.: 1492 VWR No.:15170-172</td>
			<td></td>
		</tr>
	</tbody>
</table>

live imaging to study microtubule dynamic instability in taxane-resistant breast cancers

Taxanes such as docetaxel belong to a group of microtubule-targeting agents (MTAs) that are commonly relied upon to treat cancer. However, taxane resistance in cancerous cells drastically reduces the effectiveness of the drugs' long-term usage. Accumulated evidence suggests that the mechanisms underlying taxane resistance include both general mechanisms, such as the development of multidrug resistance due to the overexpression of drug-efflux proteins, and taxane-specific mechanisms, such as those that involve microtubule dynamics. 
Because taxanes target cell microtubules, measuring microtubule dynamic instability is an important step in determining the mechanisms of taxane resistance and provides insight into how to overcome this resistance. In the experiment, an in vivo method was used to measure microtubule dynamic instability. GFP-tagged &#945;-tubulin was expressed and incorporated into microtubules in MCF-7 cells, allowing for the recording of the microtubule dynamics by time lapse using a sensitive camera. The results showed that, as opposed to the non-resistant parental MCF-7CC cells, the microtubule dynamics of docetaxel-resistant MCF-7TXT cells are insensitive to docetaxel treatment, which causes the resistance to docetaxel-induced mitotic arrest and apoptosis. This paper will outline this in vivo method of measuring microtubule dynamic instability.

Using the protocol presented here, we studied the effects of docetaxel on the microtubule dynamics of normal (MCF-7CC) and docetaxel-resistant (MCF-7TXT) breast cancer cells. Two sets of images show the effects of docetaxel (0.5 &#181;M) on microtubule growth and shortening in MCF-7CC and MCF-7TXT cells (Figure 1A).
We also calculated the rate of microtubule growth or ...

Watch this Scientific Journal Video about Live Imaging to Study Microtubule Dynamic Instability in Taxane-resistant Breast Cancers at JoVE.com

Live Imaging to Study Microtubule Dynamic Instability in Taxane-resistant Breast Cancers

In this paper, we report a protocol describing an in vivo method to measure microtubule dynamic instability in docetaxel-resistant breast cancer cells (MCF-7TXT). In this method, a deconvolution microscopy imaging system is used to detect the expression of GFP-tubulin in target cells.

Taxanes such as docetaxel belong to a group of microtubule-targeting agents (MTAs) that are commonly relied upon to treat cancer. However, taxane ...

The overall goal of this experiment is to measure microtubule dynamic instability in docetaxel resistant breast cancer cells. This method can help answer key questions in the field of cell biology about microtubule dynamic instability under physiological conditions, and following various drug treatments. The main advantages of this technique are that it provides a simple, reliable and physiologically applicable protocol for studying microtubule dynamics in living cells.Before beginning the procedure, grow the breast cancer cells in complete culture medium in 10 centimeter culture dishes at 37 degrees Celsius, and 5%carbon dioxide to the appropriate degree of confluency. The day before the experiment, rinse 24 millimeter poly L-lysine coated glass cover slips with 70%alcohol and expose the slips to UV light overnight. The next morning, place one cover slip into each well of a six well plate.Then wash the cultures with PBS, and detach the cells in each dish with 0.5 milliliters of trypsin EDTA. When the cells have begun to lift from the plate bottom, neutralize the trypsin with five milliliters of fresh culture medium and count the cells. Then add approximately one times 10 the fifth cells to each cover slip, shake the plate gently, and return the cells to the incubator for at least 36 hours.To assay the microtubule dynamics of the cells mix GFP tagged alpha tubulin stock solution several times by inversion to ensure a homogenous solution without vortexing. Then replace the culture medium in each well with two milliliters of fresh medium containing 40 microliters of the tag tubulin. Shake the plate gently to allow complete mixing of the marker with the culture medium and return the plate to the incubator for another 24 hours.The next day, replace the culture medium with fresh medium containing docetaxel and return the plate to the incubator for 30 minutes. While the cells are being inhibited, turn on the inverted fluorescence microscope, and prewarm the sample holder to 37 degrees Celsius. Then select the 60X 1.42 NA oil objective lens and mount the first cover slip onto the sample holder.Cover the sample with one milliliter of fresh 37 degree Celsius docetaxel containing medium and locate a cluster of flat cells exhibiting a high GFP tagged alpha tubulin fluorescence intensity with clearly visible microtubule structures. Focus on the peripheral area of one of the cells in the cluster, and set the appropriate exposure time in the image acquisition frequency. Exactly 50 minutes after adding the first aliquot of docetaxel begin recording the microtubule dynamics for two minutes, obtaining a photo every two seconds.When all of the images have been acquired, image the next cell as just demonstrated, until images for five cells total from all three wells of each docetaxel concentration have been captured. When all of the images have been acquired for each inhibitor concentration open the deconvolution program, within the microscope system and click process. Next, select deconvolve and drag the image file to the input window.Click do to deconvolve the image, and open the deconvolved image file within the microscope software. Click file and save as movie. Set the movie format as AV and the animation style as forward.Set the compression quality to 100%and the frame rate to five per second. Then check the animate through time box and click do it to generate the video. In this representative experiment, normal and docetaxel resistant breast cancer cells were treated with docetaxel and imaged as just demonstrated, but the effects of the treatment on microtubule growth and shortening, most evident in the non docetaxel resistant cells.Indeed, measuring the rate of microtubule growth and shortening under 0.5 micromolar docetaxel treatment conditions reveals a strong inhibition of the tubulin dynamics of parental but not docetaxel resistant cells. Once mastered, the entire process can be completed within 60 hours if the techniques are performed properly. While attempting this procedure, it is important to remember to select flat cells, with a high GFP tubulin fluorescence intensity, and to reduce both the intensity of the excitation fluorescence and the duration of exposure to avoid fading of the GFP fluorescence.Since it's development, this technique has paved the way for researchers in the fields of cell and cancer biology to assess the effects of various microtubule targeting agents on normal and cancerous cells. After watching this video, you should have a good understanding of how to measure microtubule dynamic instability in living cells under a variety of conditions.

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Here we present a methodology for generating uniform and reproducible tumor spheroids that can be subjected to siRNA functional screening. These spheroids display many characteristics that are found in solid tumors that are not present in traditional two-dimension culture. We show that several commonly used breast cancer cell lines are amenable to this protocol. Furthermore, we provide proof-of-principle data utilizing the breast cancer cell line BT474, confirming their dependency on amplification of the epidermal growth factor receptor HER2 and mutation of phosphatidylinositol-4,5-biphosphate 3-kinase (PIK3CA) when grown as tumor spheroids. Finally, we are able to further investigate and confirm the spatial impact of these dependencies using immunohistochemistry.

Identifying novel drug targets that transition from pre-clinical testing to human trials is a scientific priority. To that end, here we describe a functional genomics approach for examining the impact of gene depletion on cancer cell line spheroids, which more appropriately model human cancers in vivo.

The identification of functional driver events in cancer is central to furthering our understanding of cancer biology and indispensable for the discovery ...

A Portal Vein Injection Model to Study Liver Metastasis of Breast Cancer

Breast cancer is the leading cause of cancer-related mortality in women worldwide. Liver metastasis is involved in upwards of 30% of cases with breast cancer metastasis, and results in poor outcomes with median survival rates of only 4.8 - 15 months. Current rodent models of breast cancer metastasis, including primary tumor cell xenograft and spontaneous tumor models, rarely metastasize to the liver. Intracardiac and intrasplenic injection models do result in liver metastases, however these models can be confounded by concomitant secondary-site metastasis, or by compromised immunity due to removal of the spleen to avoid tumor growth at the injection site. To address the need for improved liver metastasis models, a murine portal vein injection method that delivers tumor cells firstly and directly to the liver was developed. This model delivers tumor cells to the liver without complications of concurrent metastases in other organs or removal of the spleen. The optimized portal vein protocol employs small injection volumes of 5 - 10 &#956;l, &#8805; 32 gauge needles, and hemostatic gauze at the injection site to control for blood loss. The portal vein injection approach in Balb/c female mice using three syngeneic mammary tumor lines of varying metastatic potential was tested; high-metastatic 4T1 cells, moderate-metastatic D2A1 cells, and low-metastatic D2.OR cells. Concentrations of &#8804; 10,000 cells/injection results in a latency of ~ 20 - 40 days for development of liver metastases with the higher metastatic 4T1 and D2A1 lines, and &#62; 55 days for the less aggressive D2.OR line. This model represents an important tool to study breast cancer metastasis to the liver, and may be applicable to other cancers that frequently metastasize to the liver including colorectal and pancreatic adenocarcinomas.

A surgical procedure was developed to deliver mammary tumor cells to the murine liver via portal vein injection. This model permits investigation of late stages of liver metastasis in a fully immune competent host, including tumor cell extravasation, seeding, survival, and metastatic outgrowth in the liver.

Breast cancer is the leading cause of cancer-related mortality in women worldwide. Liver metastasis is involved in upwards of 30% of cases with breast ...

Live-imaging of Breast Epithelial Cell Migration After the Transient Depletion of TIP60

The wound-healing assay is efficient and one of the most economical ways to study cell migration in vitro. Conventionally, images are taken at the beginning and end of an experiment using a phase-contrast microscope, and the migration abilities of cells are evaluated by the closure of wounds. However, cell movement is a dynamic phenomenon, and a conventional method does not allow for tracking single-cell movement. To improve current wound-healing assays, we use live-cell imaging techniques to monitor cell migration in real time. This method allows us to determine the cell migration rate based on a cell tracking system and provides a clearer distinction between cell migration and cell proliferation. Here, we demonstrate the use of live-cell imaging in wound-healing assays to study the different migration abilities of breast epithelial cells influenced by the presence of TIP60. As cell motility is highly dynamic, our method provides more insights into the processes of wound healing than a snapshot of wound closure taken with the traditional imaging techniques used for wound-healing assays.

Here, we present the real-time monitoring of cell migration in a wound-healing assay using TIP60-depleted MCF10A breast epithelial cells. The implementation of live-cell imaging techniques in our protocol allows us to analyze and visualize single-cell movement in real time and across time.

The wound-healing assay is efficient and one of the most economical ways to study cell migration in vitro. Conventionally, images are taken at the ...

Radionuclide-fluorescence Reporter Gene Imaging to Track Tumor Progression in Rodent Tumor Models

Metastasis is responsible for most cancer deaths. Despite extensive research, the mechanistic understanding of the complex processes governing metastasis remains incomplete. In vivo models are paramount for metastasis research, but require refinement. Tracking spontaneous metastasis by non-invasive in vivo imaging is now possible, but remains challenging as it requires long-time observation and high sensitivity. We describe a longitudinal combined radionuclide and fluorescence whole-body in vivo imaging approach for tracking tumor progression and spontaneous metastasis. This reporter gene methodology employs the sodium iodide symporter (NIS) fused to a fluorescent protein (FP). Cancer cells are engineered to stably express NIS-FP followed by selection based on fluorescence-activated cell sorting. Corresponding tumor models are established in mice. NIS-FP expressing cancer cells are tracked non-invasively in vivo at the whole-body level by positron emission tomography (PET) using the NIS radiotracer [18F]BF4-. PET is currently the most sensitive in vivo imaging technology available at this scale and enables reliable and absolute quantification. Current methods either rely on large cohorts of animals that are euthanized for metastasis assessment at varying time points, or rely on barely quantifiable 2D imaging. The advantages of the described method are: (i) highly sensitive non-invasive in vivo 3D PET imaging and quantification, (ii) automated PET tracer production, (iii) a significant reduction in required animal numbers due to repeat imaging options, (iv) the acquisition of paired data from subsequent imaging sessions providing better statistical data, and (v) the intrinsic option for ex vivo confirmation of cancer cells in tissues by fluorescence microscopy or cytometry. In this protocol, we describe all steps required for routine NIS-FP-afforded non-invasive in vivo cancer cell tracking using PET/CT and ex vivo confirmation of in vivo results. This protocol has applications beyond cancer research whenever in vivo localization, expansion and long-time monitoring of a cell population is of interest.

We describe a protocol for preclinical in vivo tracking of cancer metastasis. It is based on a radionuclide-fluorescence reporter combining the sodium iodide symporter, detected by non-invasive [18F]tetrafluoroborate-PET, and a fluorescent protein for streamlined ex vivo confirmation. The method is applicable for preclinical in vivo cell tracking beyond tumor biology.

Metastasis is responsible for most cancer deaths. Despite extensive research, the mechanistic understanding of the complex processes governing metastasis ...

Long-term Live-cell Imaging to Assess Cell Fate in Response to Paclitaxel

Live-cell imaging is a powerful technique that can be used to directly visualize biological phenomena in single cells over extended periods of time. Over the past decade, new and innovative technologies have greatly enhanced the practicality of live-cell imaging. Cells can now be kept in focus and continuously imaged over several days while maintained under 37 &#176;C and 5% CO2 cell culture conditions. Moreover, multiple fields of view representing different experimental conditions can be acquired simultaneously, thus providing high-throughput experimental data. Live-cell imaging provides a significant advantage over fixed-cell imaging by allowing for the direct visualization and temporal quantitation of dynamic cellular events. Live-cell imaging can also identify variation in the behavior of single cells that would otherwise have been missed using population-based assays. Here, we describe live-cell imaging protocols to assess cell fate decisions following treatment with the anti-mitotic drug paclitaxel. We demonstrate methods to visualize whether mitotically arrested cells die directly from mitosis or slip back into interphase. We also describe how the fluorescent ubiquitination-based cell cycle indicator (FUCCI) system can be used to assess the fraction of interphase cells born from mitotic slippage that are capable of re-entering the cell cycle. Finally, we describe a live-cell imaging method to identify nuclear envelope rupture events.

Live-cell imaging provides a wealth of information on single cells or whole populations that is unattainable by fixed cell imaging alone. Here, live-cell imaging protocols to assess cell fate decisions following treatment with the anti-mitotic drug paclitaxel are described.

Live-cell imaging is a powerful technique that can be used to directly visualize biological phenomena in single cells over extended periods of time. Over ...

Live-Cell Imaging Assays to Study Glioblastoma Brain Tumor Stem Cell Migration and Invasion

Glioblastoma (GBM) is an aggressive brain tumor that is poorly controlled with the currently available treatment options. Key features of GBMs include rapid proliferation and pervasive invasion into the normal brain. Recurrence is thought to result from the presence of radio- and chemo-resistant brain tumor stem cells (BTSCs) that invade away from the initial cancerous mass and, thus, evade surgical resection. Hence, therapies that target BTSCs and their invasive abilities may improve the otherwise poor prognosis of this disease. Our group and others have successfully established and characterized BTSC cultures from GBM patient samples. These BTSC cultures demonstrate fundamental cancer stem cell properties such as clonogenic self-renewal, multi-lineage differentiation, and tumor initiation in immune-deficient mice. In order to improve on the current therapeutic approaches for GBM, a better understanding of the mechanisms of BTSC migration and invasion is necessary. In GBM, the study of migration and invasion is restricted, in part, due to the limitations of existing techniques which do not fully account for the in vitro growth characteristics of BTSCs grown as neurospheres. Here, we describe rapid and quantitative live-cell imaging assays to study both the migration and invasion properties of BTSCs. The first method described is the BTSC migration assay which measures the migration toward a chemoattractant gradient. The second method described is the BTSC invasion assay which images and quantifies a cellular invasion from neurospheres into a matrix. The assays described here are used for the quantification of BTSC migration and invasion over time and under different treatment conditions.

Here, we describe live-cell imaging techniques to quantitatively measure the migration and invasion of glioblastoma brain tumor stem cells over time and under multiple treatment conditions.

Glioblastoma (GBM) is an aggressive brain tumor that is poorly controlled with the currently available treatment options. Key features of GBMs include ...

Studying Triple Negative Breast Cancer Using Orthotopic Breast Cancer Model

Triple-negative breast cancer (TNBC) is an aggressive breast cancer subtype with limited therapeutic options. When compared to patients with less aggressive breast tumors, the 5-year survival rate of TNBC patients is 77% due to their characteristic drug-resistant phenotype and metastatic burden. Toward this end, murine models have been established aimed at identifying novel therapeutic strategies limiting TNBC tumor growth and metastatic spread. This work describes a practical guide for the TNBC orthotopic model where MDA-MB-231 breast cancer cells suspended in a basement membrane matrix are implanted in the fourth mammary fat pad, which closely mimics the cancer cell behavior in humans. Measurement of tumors by caliper, lung metastasis assessment via in vivo and ex vivo imaging, and molecular detection are discussed. This model provides an excellent platform to study therapeutic efficacy and is especially suitable for the study of the interaction between the primary tumor and distal metastatic sites.

This work presets an advanced protocol to accurately assess tumor loading by detection of green fluorescent protein and bioluminescence signals as well as the integration of quantitative molecular detection technique.

Triple-negative breast cancer (TNBC) is an aggressive breast cancer subtype with limited therapeutic options. When compared to patients with less ...

Using the Chicken Chorioallantoic Membrane In Vivo Model to Study Gynecological and Urological Cancers

Mouse models are the benchmark tests for in vivo cancer studies. However, cost, time, and ethical considerations have led to calls for alternative in vivo cancer models. The chicken chorioallantoic membrane (CAM) model provides an inexpensive, rapid alternative that permits direct visualization of tumor development and is suitable for in vivo imaging. As such, we sought to develop an optimized protocol for engrafting gynecological and urological tumors into this model, which we present here. Approximately 7 days postfertilization, the air cell is moved to the vascularized side of the egg, where an opening is created in the shell. Tumors from murine and human cell lines and primary tissues can then be engrafted. These are typically seeded in a mixture of extracellular matrix and medium to avoid cellular dispersal and provide nutrient support until the cells recruit a vascular supply. Tumors may then grow for up to an additional 14 days prior to the eggs hatching. By implanting cells stably transduced with firefly luciferase, bioluminescence imaging can be used for the sensitive detection of tumor growth on the membrane and cancer cell spread throughout the embryo. This model can potentially be used to study tumorigenicity, invasion, metastasis, and therapeutic effectiveness. The chicken CAM model requires significantly less time and financial resources compared to traditional murine models. Because the eggs are immunocompromised and immune tolerant, tissues from any organism can potentially be implanted without costly transgenic animals (e.g., mice) required for implantation of human tissues. However, many of the advantages of this model could potentially also be limitations, including the short tumor generation time and immunocompromised/immune tolerant status. Additionally, although all tumor types presented here engraft in the chicken chorioallantoic membrane model, they do so with varying degrees of tumor growth.

We present the chicken chorioallantoic membrane model as an alternative, transplantable, in vivo model for the engraftment of gynecological and urological cancer cell lines and patient-derived tumors.

Mouse models are the benchmark tests for in vivo cancer studies. However, cost, time, and ethical considerations have led to calls for alternative in vivo ...

Combined Use of Tail Vein Metastasis Assays and Real-Time In Vivo Imaging to Quantify Breast Cancer Metastatic Colonization and Burden in the Lungs

Metastasis is the main cause of cancer-related deaths and there are limited therapeutic options for patients with metastatic disease. The identification and testing of novel therapeutic targets that will facilitate the development of better treatments for metastatic disease requires preclinical in vivo models. Demonstrated here is a syngeneic mouse model for assaying breast cancer metastatic colonization and subsequent growth. Metastatic cancer cells are stably transduced with viral vectors encoding firefly luciferase and ZsGreen proteins. Candidate genes are then stably manipulated in luciferase/ZsGreen-expressing cancer cells and then the cells are injected into mice via the lateral tail vein to assay metastatic colonization and growth. An in vivo imaging device is then used to measure the bioluminescence or fluorescence of the tumor cells in the living animals to quantify changes in metastatic burden over time. The expression of the fluorescent protein allows the number and size of metastases in the lungs to be quantified at the end of the experiment without the need for sectioning or histological staining. This approach offers a relatively quick and easy way to test the role of candidate genes in metastatic colonization and growth, and provides a great deal more information than traditional tail vein metastasis assays. Using this approach, we show that simultaneous knockdown of Yes associated protein (YAP) and transcriptional co-activator with a PDZ-binding motif (TAZ) in breast cancer cells leads to reduced metastatic burden in the lungs and that this reduced burden is the result of significantly impaired metastatic colonization and reduced growth of metastases.

The described approach combines experimental tail vein metastasis assays with in vivo live animal imaging to allow real-time monitoring of breast cancer metastasis formation and growth in addition to the quantification of metastasis number and size in the lungs.

Metastasis is the main cause of cancer-related deaths and there are limited therapeutic options for patients with metastatic disease. The identification ...

Modeling Breast Cancer in Human Breast Tissue using a Microphysiological System

Breast cancer (BC) remains a leading cause of death for women. Despite more than $700 million invested in BC research annually, 97% of candidate BC drugs fail clinical trials. Therefore, new models are needed to improve our understanding of the disease. The NIH Microphysiological Systems (MPS) program was developed to improve the clinical translation of basic science discoveries and promising new therapeutic strategies. Here we present a method for generating MPS for breast cancers (BC-MPS). This model adapts a previously described approach of culturing primary human white adipose tissue (WAT) by sandwiching WAT between adipose-derived stem cell sheets (ASC)s. Novel aspects of our BC-MPS include seeding BC cells into non-diseased human breast tissue (HBT) containing native extracellular matrix, mature adipocytes, resident fibroblasts, and immune cells; and sandwiching the BC-HBT admixture between HBT-derived ASC sheets. The resulting BC-MPS is stable in culture ex vivo for at least 14 days. This model system contains multiple elements of the microenvironment that influence BC including adipocytes, stromal cells, immune cells, and the extracellular matrix. Thus BC-MPS can be used to study the interactions between BC and its microenvironment. 
We demonstrate the advantages of our BC-MPS by studying two BC behaviors known to influence cancer progression and metastasis: 1) BC motility and 2) BC-HBT metabolic crosstalk. While BC motility has previously been demonstrated using intravital imaging, BC-MPS allows for high-resolution time-lapse imaging using fluorescence microscopy over several days. Furthermore, while metabolic crosstalk was previously demonstrated using BC cells and murine pre-adipocytes differentiated into immature adipocytes, our BC-MPS model is the first system to demonstrate this crosstalk between primary human mammary adipocytes and BC cells in vitro.

This protocol describes the construction of an in vitro microphysiological system for studying breast cancer using primary human breast tissue with off the shelf materials.

Breast cancer (BC) remains a leading cause of death for women. Despite more than $700 million invested in BC research annually, 97% of candidate BC drugs ...