Name: a genetically engineered mouse model of sporadic colorectal cancer
Uploaded: 2017-07-06T12:30:00
Description: Watch this Scientific Journal Video about A Genetically Engineered Mouse Model of Sporadic Colorectal Cancer at JoVE.com

Detta arbete är tillägnad minnet av professor Moritz Koch.

De djurförsök som presenteras här utvärderades oberoende av och godkändes av en institutionell och en statlig djurvårds- och användningskommitté och genomfördes enligt riktlinjerna för FELASA (Federation of Laboratory Animal Science Associations). Alla möjliga åtgärder vidtogs för att minimera lidande inklusive anestesi och analgesi eller vid behov prematur eutanasi. 1. Lokal tumörinduktion via kirurgisk adeno-cre-infektion <ol><li> Framställning av djur f?...

<ol>
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D., Jemal, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cancer+statistics,+2016.">Cancer statistics, 2016.</a> CA Cancer J Clin. 66 (1), 7-30 (2016).</li><li>Weitz, 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=Colorectal+cancer.">Colorectal cancer.</a> Lancet. 365 (9454), 153-165 (2005).</li><li>Bork, U., 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=Prognostic+relevance+of+minimal+residual+disease+in+colorectal+cancer.">Prognostic relevance of minimal residual disease in colorectal cancer.</a> World J Gastroenterol. 20 (30), 10296-10304 (2014).</li><li>Steinert, G., Sch&#246;lch, S., Koch, M., Weitz, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biology+and+significance+of+circulating+and+disseminated+tumour+cells+in+colorectal+cancer.">Biology and significance of circulating and disseminated tumour cells in colorectal cancer.</a> Langenbecks Arch Surg. 397 (4), 535-542 (2012).</li><li>Garc&#237;a, S. 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=LDB1+overexpression+is+a+negative+prognostic+factor+in+colorectal+cancer.">LDB1 overexpression is a negative prognostic factor in colorectal cancer.</a> Oncotarget. 7 (51), 84258-84270 (2016).</li><li>van Noort, V., 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=Novel+Drug+Candidates+for+the+Treatment+of+Metastatic+Colorectal+Cancer+through+Global+Inverse+Gene-Expression+Profiling.">Novel Drug Candidates for the Treatment of Metastatic Colorectal Cancer through Global Inverse Gene-Expression Profiling.</a> Cancer Res. 74 (20), 5690-5699 (2014).</li><li>Nanduri, L. K., Garc&#237;a, S., Weitz, J., Sch&#246;lch, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mouse+Models+of+Colorectal+Cancer-Derived+Circulating+Tumor+Cells.">Mouse Models of Colorectal Cancer-Derived Circulating Tumor Cells.</a> Med Chem (Los Angeles). 6 (7), 497-499 (2016).</li><li>Taketo, M. M., Edelmann, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mouse+models+of+colon+cancer.">Mouse models of colon cancer.</a> Gastroenterology. 136 (3), 780-798 (2009).</li><li>Sch&#246;lch, S., 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=Circulating+tumor+cells+exhibit+stem+cell+characteristics+in+an+orthotopic+mouse+model+of+colorectal+cancer.">Circulating tumor cells exhibit stem cell characteristics in an orthotopic mouse model of colorectal cancer.</a> Oncotarget. 7 (19), 27232-27242 (2016).</li><li>Sch&#246;lch, S., 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=Radiotherapy+combined+with+TLR7/8+activation+induces+strong+immune+responses+against+gastrointestinal+tumors.">Radiotherapy combined with TLR7/8 activation induces strong immune responses against gastrointestinal tumors.</a> Oncotarget. 6 (7), 4663-4676 (2015).</li><li>Corbett, T. 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E., 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=Development+of+a+mouse+model+for+sporadic+and+metastatic+colon+tumors+and+its+use+in+assessing+drug+treatment.">Development of a mouse model for sporadic and metastatic colon tumors and its use in assessing drug treatment.</a> Proc Natl Acad Sci USA. 107 (4), 1565-1570 (2010).</li><li>Sharpless, N. E., Depinho, R. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+mighty+mouse:+genetically+engineered+mouse+models+in+cancer+drug+development.">The mighty mouse: genetically engineered mouse models in cancer drug development.</a> Nat Rev Drug Discov. 5 (9), 741-754 (2006).</li><li>Shibata, 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=Rapid+colorectal+adenoma+formation+initiated+by+conditional+targeting+of+the+Apc+gene.">Rapid colorectal adenoma formation initiated by conditional targeting of the Apc gene.</a> Science. 278 (5335), 120-123 (1997).</li><li>Kuraguchi, 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=Adenomatous+polyposis+coli+(APC)+is+required+for+normal+development+of+skin+and+thymus.">Adenomatous polyposis coli (APC) is required for normal development of skin and thymus.</a> PLoS Genet. 2 (9), e146 (2006).</li><li>Jackson, E. 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=Analysis+of+lung+tumor+initiation+and+progression+using+conditional+expression+of+oncogenic+K-ras.">Analysis of lung tumor initiation and progression using conditional expression of oncogenic K-ras.</a> Genes Dev. 15 (24), 3243-3248 (2001).</li><li>Olive, K. 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F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High+resolution+colonoscopy+in+live+mice.">High resolution colonoscopy in live mice.</a> Nat Protoc. 1 (6), 2900-2904 (2006).</li><li>Moser, A. R., Pitot, H. C., Dove, W. 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Medan de generellt är lätta att generera och underhålla, är klassiska CRC-musmodeller baserade på cellinjektion artificiella och kan inte fullständigt rekapitulera den mänskliga sjukdomen. Som en konsekvens har GEMMs utvecklats. Den första CRC GEMM var Apc Min- musen, som har en heterozygot null-mutation i Apc-genen, och efterliknar därför den mänskliga ärftliga sjukdomen familial adenomatous polyposis (FAP). 21 Apc Min- möss utvecklar emellertid oundvikligen fl...

Colorectal cancer (CRC) fortsätter att vara en av de främsta orsakerna till cancerrelaterad död i västra länder. 1 Även om prognosen hos patienter med tidig sjukdom är bra, diagnostiseras många tumörer vid senare skeden, där prognosen är begränsad trots många behandlingsalternativ. 2 , 3 , 4 , 5 Majoriteten av nuvarande musmodeller av CRC är baserade på implantering av tumörceller härledda från cellinjer eller patienttumörer till immundeficenta möss. 6 , 7 , 8 Detta leder till lokala och, beroende på injektionsstället och de tumörceller som används för injektion, ibland metastatiska tumörer. 9 , 10 De resulterande xenograftmodellerna har emellertid majoR begränsningar. De måste etableras i immunbristande möss, vilket eliminerar den komplexa interaktionen mellan tumören och värdimmunsystemet. Eftersom tumörstromen härleds från värdceller är dessutom interaktionen mellan humant tumörparenkym och murin stroma defekt och därför inte representativ för sjukdomen. Dessa brister kan undvikas genom användning av murincellinjer för injektion. Emellertid är endast få murina CRC-cellinjer tillgängliga och, liknande de flesta tillgängliga humana CRC-cellinjer, är monoklonala och mycket anaplastiska. 11 Sammanfattningsvis är de flesta tillgängliga CRC-musmodellerna mycket artificiella och inte fullständigt representativa för den mänskliga sjukdomen. Genetiskt manipulerade musmodeller (GEMM) hos CRC kan undvika dessa nackdelar, eftersom de uppvisar äkta mustumörer som skapas via induktion av nyckelmutationer av CRC i kolon. 12 , 13 ,14 Detta kan åstadkommas genom aktivering av betingade (floxed) kimlinjemutationer genom cre rekombinas inom kolorektal slemhinna. Medan i GEMM från många andra tumörenheter används germline (inducerbart) cre-uttryck som drivs av vävnadsspecifika promotorer, kan germline cre inte användas i tjocktarmen, eftersom detta leder till ett stort antal adenomer i hela tjocktarmen som orsakar död genom godartad tumörbelastning vid En mycket ung ålder. Därför används i den här beskrivna modellen en adenoviral vektoruttryckande cre för att infektera ett kort tjocktarmsegment. Detta leder till induktion av tumörgenesen inom detta segment av slemhinnan vid en tidpunkt som definierats av undersökaren, vilket resulterar i adenomer som i slutändan utvecklas till invasivt och metastatiskt karcinom. Tumörerna är äkta mustumörer, växer i en intakt mikromiljö och kan därför simulera helheten av kolorektal onkogenes inklusive tumör-värd-interaktion och metastatisk kaskad. Denna modell ärDärför en attraktiv plattform för studier av cancerbiologi och prekliniska terapeutiska studier. En stor nackdel med genetiskt modifierade musmodeller av CRC är deras tekniska komplexitet. Lokal cre-leverans med användning av rektala adeno-cre-enemas i möss som bär floxade Apc-alleler har beskrivits tidigare; Emellertid kan incidensen, multipliciteten och placeringen av tarmtumörerna vara mycket variabel med denna teknik. 15 Därför har tekniken att begränsa adeno-cre-infektionen genom kirurgisk klämning av segmentet som skall induceras utvecklats. 13 Vi har ändrat denna procedur för att förbättra djurs välbefinnande, samt minska dödligheten och antalet resulterande tumörer. Med detta protokoll bör alla laboratorier med erfarenhet av liten gnagareoperation kunna reproducera modellen och producera tumörer som är mycket reproducerbara och lättillgängliga för koloskopi. Beroende på den villkorliga mUtationer som används för tumörigenes, hela spektret av adenom, invasivt karcinom och metastaser kan observeras. Eftersom tumörerna ligger i distal kolon, är seriell endoskopisk bedömning lätt möjlig i denna modell.

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	<tbody>
		<tr>
			<td>Reagents / consumables</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Dulbecco&#39;s Phosphate Buffered Saline</td>
			<td>Life Technologies GmbH</td>
			<td>14190169</td>
			<td></td>
		</tr>
		<tr>
			<td>Trypsin-EDTA (0.25%, Phenol-Red)</td>
			<td>Life Technologies GmbH</td>
			<td>25200072</td>
			<td></td>
		</tr>
		<tr>
			<td>Normal saline 0.9% (E154)</td>
			<td>Serumwerk Bernburg AG</td>
			<td>10013</td>
			<td></td>
		</tr>
		<tr>
			<td>Aqua ad injectabilia</td>
			<td>B. Braun Melsungen AG</td>
			<td>235144</td>
			<td></td>
		</tr>
		<tr>
			<td>Ad5CMV-Cre (adenovirus, c = 2E+11 PFU/mL)</td>
			<td>Gene Transfer Vector Core 
			University of Iowa</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>15 mL, 50 mL centrifuge tubes</td>
			<td>Greiner Bio-One GmbH</td>
			<td>188271/227270</td>
			<td></td>
		</tr>
		<tr>
			<td>Eppendorf tubes 1.5 mL/ 2 mL</td>
			<td>Sarstedt AG &#38; Co.</td>
			<td>72,695,400</td>
			<td></td>
		</tr>
		<tr>
			<td>Petri dish PS 100/15 mm (sterile, Nuclon)</td>
			<td>Fisher Scientific GmbH</td>
			<td>10508921/ NUNC150350</td>
			<td></td>
		</tr>
		<tr>
			<td>1 mL Syringe (without dead volume) - Injekt-F SOLO</td>
			<td>Braun/neoLab</td>
			<td>194291661</td>
			<td></td>
		</tr>
		<tr>
			<td>30G injection needle</td>
			<td>BECTON DICKINSON</td>
			<td>304000</td>
			<td></td>
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		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
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		<tr>
			<td>Analgesia / anesthesia</td>
			<td></td>
			<td></td>
			<td></td>
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		<tr>
			<td>Sevoflurane (Sevoflurane AbbVie)</td>
			<td>AbbVie Germany GmbH &#38; Co. KG</td>
			<td>-</td>
			<td></td>
		</tr>
		<tr>
			<td>Medical oxygen</td>
			<td>Air Liquide Medical GmbH</td>
			<td>-</td>
			<td></td>
		</tr>
		<tr>
			<td>Buprenorphine (Temgesic)</td>
			<td>Indivior Eu Ltd.</td>
			<td>-</td>
			<td></td>
		</tr>
		<tr>
			<td>Bepanthen - ophthalmic ointment</td>
			<td>Bayer Vital GmbH</td>
			<td>10047757</td>
			<td></td>
		</tr>
		<tr>
			<td>Table Top Research Anesthesia Machine x/O2 Flush w/ Sevoflurane Vaporizer</td>
			<td>Parkland Scientific</td>
			<td>V3000PS/PK</td>
			<td></td>
		</tr>
		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
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			<td>Surgical Equipment</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Cellulose swabs</td>
			<td>Lohmann &#38; Rauscher Deutschland</td>
			<td>13356</td>
			<td></td>
		</tr>
		<tr>
			<td>Insulin syringe EMG 1 mL (with 30G cannula)</td>
			<td>B. Braun Melsungen AG</td>
			<td>9161627S</td>
			<td></td>
		</tr>
		<tr>
			<td>Fine Bore Tubing (bore: 0.28 mm/ diameter: 0.61mm)</td>
			<td>Smiths Medical Deutschland</td>
			<td>800/100/100</td>
			<td></td>
		</tr>
		<tr>
			<td>Micro-Adson Forceps</td>
			<td>Fine Science Tools</td>
			<td>11018-12</td>
			<td></td>
		</tr>
		<tr>
			<td>Iris Scissor - ToughCut</td>
			<td>Fine Science Tools</td>
			<td>14058-11</td>
			<td></td>
		</tr>
		<tr>
			<td>Olsen-Hegar Needle Holder</td>
			<td>Fine Science Tools</td>
			<td>12002-12</td>
			<td></td>
		</tr>
		<tr>
			<td>AutoClip Kit</td>
			<td>Fine Science Tools</td>
			<td>12020-00</td>
			<td></td>
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		<tr>
			<td>PDS Z1012H 6/0 C1 (surgical suture)</td>
			<td>Johnson &#38; Johnson Medical GmbH</td>
			<td>Z1012H</td>
			<td></td>
		</tr>
		<tr>
			<td>Curved Micro Serrefine Vascular Clamp</td>
			<td>Fine Science Tools</td>
			<td>18055-05</td>
			<td></td>
		</tr>
		<tr>
			<td>Fogarty Spring Clips</td>
			<td>Edwards</td>
			<td>CDSAFE 6</td>
			<td></td>
		</tr>
		<tr>
			<td>Hot Plate 062</td>
			<td>Labotect</td>
			<td>13854</td>
			<td></td>
		</tr>
		<tr>
			<td>Isis - Hair shaver</td>
			<td>Aesculap - Braun</td>
			<td>-</td>
			<td></td>
		</tr>
		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
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		<tr>
			<td>Colonoscopy</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Cold Light Fountain XENON 175 SCB</td>
			<td>Karl Storz</td>
			<td>20132101-1</td>
			<td>Karl Storz Coloview System Mainz</td>
		</tr>
		<tr>
			<td>Fiber Optic Light Cable</td>
			<td>Karl Storz</td>
			<td>69495NL</td>
			<td>Karl Storz Coloview System Mainz</td>
		</tr>
		<tr>
			<td>TRICAM Three-Chip Camera Head</td>
			<td>Karl Storz</td>
			<td>20221030</td>
			<td>Karl Storz Coloview System Mainz</td>
		</tr>
		<tr>
			<td>TRICAM SLII Camera Control Unit</td>
			<td>Karl Storz</td>
			<td>20223011-1</td>
			<td>Karl Storz Coloview System Mainz</td>
		</tr>
		<tr>
			<td>15&#34; Flat Screen Monitor EndoVue</td>
			<td>Karl Storz</td>
			<td>9415NN</td>
			<td>Karl Storz Coloview System Mainz</td>
		</tr>
		<tr>
			<td>HOPKINS Straight Forward Telescope 
			diameter 1.9 mm; length 10 cm 
			autoclavable 
			fiber optic light transmission incorporated</td>
			<td>Karl Storz</td>
			<td>64301AA</td>
			<td></td>
		</tr>
		<tr>
			<td>Protection and Examination Sheath</td>
			<td>Karl Storz</td>
			<td>61029C</td>
			<td></td>
		</tr>
	</tbody>
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a genetically engineered mouse model of sporadic colorectal cancer

Trots fördelarna med enkel användbarhet och kostnadseffektivitet har muskelmodeller med kolorektal cancer baserat på tumörcellinsprutning svåra begränsningar och simulerar inte noggrant tumörbiologi och tumörcellspridning. Genetiskt konstruerade musmodeller har införts för att övervinna dessa begränsningar; Emellertid är sådana modeller tekniskt krävande, speciellt i stora organ, såsom kolon, i vilket endast en enda tumör önskas. Som ett resultat av detta utvecklades en immunokompetent, genetiskt konstruerad musmodell av kolorektal cancer som utvecklar starkt likformiga tumörer och kan användas för tumörbiologiska studier såväl som terapeutiska försök. Tumörutveckling initieras genom kirurgisk, segmentinfektion i distal kolon med adeno-cre-virus i kompositionen villkorligt mutanta möss. Tumörerna kan lätt detekteras och övervakas via koloskopi. Här beskrivs kirurgisk teknik för segmentad adeno-cre-infektion avKolon, övervakning av tumören via kolonoskopi med hög upplösning och uppvisande de resulterande kolorektala tumörerna.

Om adekvat utförs, utvecklar&gt; 85% av djuren tumörer. Dödligheten för det här presenterade kirurgiska förfarandet är &lt;5%, dödligheten i koloskopi är praktiskt taget obefintlig. I de flesta möss detekteras en enda skada; I ca 30% kan 2-3 små adenom detekteras som normalt smälter till en enda tumör inom 2-3 veckor efter tumörinduktion. Fenotypen och biologiskt beteende hos de resulterande tumörerna är starkt...

Watch this Scientific Journal Video about A Genetically Engineered Mouse Model of Sporadic Colorectal Cancer at JoVE.com

A Genetically Engineered Mouse Model of Sporadic Colorectal Cancer

En genetiskt konstruerad musmodell av sporadisk kolorektal cancer

Ett protokoll för upprättandet av en genmodifierad musmodell av kolorektal cancer genom segmentad adeno-cre-infektion och dess övervakning via kolonoskopi med hög upplösning presenteras.

Despite the advantages of easy applicability and cost-effectiveness, colorectal cancer mouse models based on tumor cell injection have severe limitations ...

The overall goal of this procedure is to achieve segmental adeno-cre infection of the colon in a genetically engineered mouse model. This method can help answer key questions in the field of colorectal cancer, or CRC, as it provides an excellent model for studying the biology and treatment of CRC. The main advantage of this technique is that any lab with small rodent surgery experience can use this model to produce highly reproducible and easily accessible colon-localized tumors.Begin by placing an anesthetized mouse in the supine position and apply ointment to the animal's eyes. Tape the mouse in a secure position and then confirm the appropriate level of sedation by toe pinch. Make an approximately 15-millimeter midline incision in the skin of the lower abdomen.Then, use forceps to grasp the abdominal wall musculature and carefully incise the muscle with scissors to open the abdominal cavity. After identifying the distal colon, carefully clinch the tissue with a delicate clamp approximately 15 millimeters proximal to the anus. Next, insert a flexible Teflon tube transanally carefully advancing the tube until it reaches the luminal occlusion.Encannulate the tube with a 30-gauge cannula. Connect a standard one-milliliter syringe to the cannula and flush the colon with several milliliters of normal saline until all of the fecal matter has been evacuated. Once the distal colon is empty, replace the saline tube with a new Teflon tube and use a second clamp to occlude the colon approximately three millimeters distal to the first clamp.Using a second one-milliliter syringe equipped with a 30-gauge cannula, carefully inject 50 to 80 microliters of 0.25%trypsin-EDTA into the clamped colon segment. The colon should inflate enough to break up the mucosal barrier without perforating the clamped tissue segment. After 10 minutes, remove the distal clamp.Then, remove the trypsin tube and flush the distal colon with 500 microliters of normal saline. After inserting a new Teflon tube, clamp the colon again and inflate the tissue with 50 to 80 microliters of the adenoviral solution. After 30 minutes, remove the clamps and the tube and close the abdominal wall with 6-0 rapidly absorbable running sutures.Close the skin with surgical wound clips and monitor the animal on a heating pad until it is fully recovered. To monitor tumor growth via colonoscopy, place the anesthetized tumor-bearing animal in the supine position on a heating pad and transanally insert the endoscope into the intestinal tract. Gently insufflate air under visual control to distend the colon.Then, carefully push the scope forward until a mucosal lesion can be identified in the distal colon saving each endoscopic image as it is acquired for later evaluation. When all of the images have been obtained, slowly remove the endoscope and place the mouse on a 38-degree-Celsius heating pad until fully recovered. The tumors can be easily and repeatedly monitored via colonoscopy without major stress for the animals.The disease manifestations are very similar to the human colorectal cancer with the animals first developing adenomas followed ultimately by adenocarcinoma development in the distal colon. Depending on the conditional genotype of the animals, the tumors also metastasize to the peritoneum and the liver. If a fluorescent cre-reporter allele is used, the tumor manifestations can be easily identified by fluorescent protein expression which depending on the reporter allele, may be bright enough to be visualized in daylight.Histologically, 95%of the developing tumors are adenocarcinomas closely resembling human colorectal cancer and feature the entire spectrum of tumor development from non-invasive adenoma to adenocarcinoma invading the surrounding structures. Once mastered, this technique can be completed in 50 minutes if it's performed properly. While attempting this procedure, it is important to remember to give special attention to the vulnerability of the colon at all times.Perforation inevitably leads to peritonitis and sepsis and requires a termination of the enema. Don't forget that working with adenovirus requires biosafety level two safety measures as the virus can be hazardous.

Research

JoVE Journal

Cancer Research

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