NIH funding through National Cancer Institute, grant # CA228582. Shun Ishiyama is currently receiving a grant from Toray Medical Co., Ltd.

All the procedures and experiments involving rats were performed according to protocols approved by Johns Hopkins Animal Care and Use Committee.
1. The SD rat OS cell line UMR-106 cell culture protocol
<ol>
	<li>Grow cells in DMEM, supplemented with 10% (v/v) FBS, penicillin (10 U/mL)-streptomycin (10 U/mL) at 37 &#176;C in humidified 5% CO2 atmosphere. Perform experiments using cells with passages of 2-812.</li>
</ol>
2. Intratibial i...

<ol>
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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=Prognostic+factors+in+high-grade+osteosarcoma+of+the+extremities+or+trunk:+an+analysis+of+1,702+patients+treated+on+neoadjuvant+cooperative+osteosarcoma+study+group+protocols.">Prognostic factors in high-grade osteosarcoma of the extremities or trunk: an analysis of 1,702 patients treated on neoadjuvant cooperative osteosarcoma study group protocols.</a> Journal of Clinical Oncology. 20 (3), 776-790 (2002).</li><li>Botter, S. M., Neri, D., Fuchs, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recent+advances+in+osteosarcoma.">Recent advances in osteosarcoma.</a> Current Opinion in Pharmacology. 16, 15-23 (2014).</li><li>Ek, E. T. H., Dass, C. R., Choong, P. F. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Commonly+used+mouse+models+of+osteosarcoma.">Commonly used mouse models of osteosarcoma.</a> Critical Reviews in Oncology Hematology. 60 (1), 1-8 (2006).</li><li>Guijarro, M. V., Ghivizzani, S. C., Gibbs, C. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Animal+models+in+osteosarcoma.">Animal models in osteosarcoma.</a> Frontiers Oncology. 4, 189 (2014).</li><li>Janeway, K. A., Walkley, C. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Modeling+human+osteosarcoma+in+the+mouse:+From+bedside+to+bench.">Modeling human osteosarcoma in the mouse: From bedside to bench.</a> Bone. 47 (5), 859-865 (2010).</li><li>Mohseny, A. B., Hogendoorn, P. C., Cleton-Jansen, A. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Osteosarcoma+models:+from+cell+lines+to+zebrafish.">Osteosarcoma models: from cell lines to zebrafish.</a> Sarcoma. 2012, 417271 (2012).</li><li>Khanna, C., 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=An+orthotopic+model+of+murine+osteosarcoma+with+clonally+related+variants+differing+in+pulmonary+metastatic+potential.">An orthotopic model of murine osteosarcoma with clonally related variants differing in pulmonary metastatic potential.</a> Clinical &amp; Experimental Metastasis. 18 (3), 261-271 (2000).</li><li>Martin, T. 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=Parathyroid+hormone-responsive+adenylate+cyclase+in+induced+transplantable+osteogenic+rat+sarcoma.">Parathyroid hormone-responsive adenylate cyclase in induced transplantable osteogenic rat sarcoma.</a> Nature. 260 (5550), 436-438 (1976).</li><li>Fisher, J. L., Mackie, P. S., Howard, M. L., Zhou, H., Choong, P. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+expression+of+the+urokinase+plasminogen+activator+system+in+metastatic+murine+osteosarcoma:+an+in+vivo+mouse+model.">The expression of the urokinase plasminogen activator system in metastatic murine osteosarcoma: an in vivo mouse model.</a> Clinical Cancer Research. 7 (6), 1654-1660 (2001).</li><li>Yu, Z., 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=Establishment+of+reproducible+osteosarcoma+rat+model+using+orthotopic+implantation+technique.">Establishment of reproducible osteosarcoma rat model using orthotopic implantation technique.</a> Oncology Reports. 21 (5), 1175-1180 (2009).</li><li>Zhang, P., 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=Homologous+mesenchymal+stem+cells+promote+the+emergence+and+growth+of+pulmonary+metastases+of+the+rat+osteosarcoma+cell+line+UMR-106.">Homologous mesenchymal stem cells promote the emergence and growth of pulmonary metastases of the rat osteosarcoma cell line UMR-106.</a> Oncology Letters. 8 (1), 127-132 (2014).</li><li>Gabrielson, K., 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=Heat+shock+protein+90+and+ErbB2+in+the+cardiac+response+to+doxorubicin+injury.">Heat shock protein 90 and ErbB2 in the cardiac response to doxorubicin injury.</a> Cancer Research. 67 (4), 1436-1441 (2007).</li><li>Sysa-Shah, P., 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=Bidirectional+cross-regulation+between+ErbB2+and+&#946;-adrenergic+signalling+pathways.">Bidirectional cross-regulation between ErbB2 and &#946;-adrenergic signalling pathways.</a> Cardiovascular Research. 109 (3), 358-373 (2016).</li><li>Wachtman, L. M., Browning, M. D., Bedja, D., Pin, S., Gabrielson, K. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Validation+of+the+use+of+long-term+indwelling+jugular+catheters+in+a+rat+model+of+cardiotoxicity.">Validation of the use of long-term indwelling jugular catheters in a rat model of cardiotoxicity.</a> Journal of American Association Laboratory Animal Science. 45, 55-64 (2006).</li><li>Abdou, A. G., 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=The+Prognostic+role+of+Ezrin+and+HER2/neu+expression+in+osteosarcoma.">The Prognostic role of Ezrin and HER2/neu expression in osteosarcoma.</a> Applied Immunohistochemistry &amp; Molecular Morphology. 24 (5), 355-363 (2016).</li><li>Hughes, D. P., Thomas, D. G., Giordano, T. J., McDonagh, K. T., Baker, L. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Essential+erbB+family+phosphorylation+in+osteosarcoma+as+a+target+for+CI-1033+inhibition.">Essential erbB family phosphorylation in osteosarcoma as a target for CI-1033 inhibition.</a> Pediatric Blood &amp; Cancer. 46 (5), 614-623 (2006).</li><li>Wen, Y. 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=Epidermal+growth+factor+receptor+in+osteosarcoma:+expression+and+mutational+analysis.">Epidermal growth factor receptor in osteosarcoma: expression and mutational analysis.</a> Human Pathology. 38 (8), 1184-1191 (2007).</li><li>Khanna, C., 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=Toward+a+drug+development+path+that+targets+metastatic+progression+in+osteosarcoma.">Toward a drug development path that targets metastatic progression in osteosarcoma.</a> Clinical Cancer Research. 20 (16), 4200-4209 (2014).</li></ol>

Rats with OS tibial implants develop measurable tumors by 3 weeks post-implantation. If limbs with tumors are amputated 3 weeks post-implantation, the incidence of lung metastasis is reduced significantly. OSs are both osteolytic and osteoblastic. Rats without amputation develop lung metastases that are multiple and variably sized, observed by radiography or at necropsy by 7 weeks post-implantation.EGFR, ErbB2, and ErbB4 are expressed in rat UMR106 OS, similar to human OS16,<sup class="...

Osteosarcoma (OS) is the most common primary bone tumor in children, adolescents, and young adults. The most recent advance in the treatment of OS occurred in the 1980s when multi-agent chemotherapy was shown to improve overall survival compared to surgery alone1. OS develops during rapid bone growth, typically occurring in long tubular bones such as femur, tibia, and humerus. They are characterized by an osteolytic, osteoblastic, or mixed appearance with notable periosteal reaction2. Chemotherapy and surgical resection can improve the outcome for patients with a 5-year survival for 65% of patients2,3. Unfortunately, high grade OS patients with metastatic disease have 20% survival. OS invades regionally and metastasizes primarily to the lungs or other bones and is more prevalent in males. The most compelling need for these young patients is a novel therapy that prevents and eliminates viability of distant metastases.
OS pre-clinical models have been reviewed4,5,6,7 and few available immunocompetent models using amputation of orthotopic OS have been developed. In 2000, an important model was developed using BALB/c mice with orthotopic syngeneic OS and amputation8. Compared to this mouse model, the rat model is based on genetically outbred and 10 times larger animals leading to some advantages. The rat UMR106 model was developed from a 32P induced OS in a Sprague Dawley (SD) rat, which was derived into a cell line9. In 2001, orthotopic implantation of UMR106-01 was first described in implanted tibias of athymic mice with rapid, consistent primary tumor development and radiological, histologic features in common with OS in humans. Pulmonary metastases developed and were dependent on orthotopic placement of UMR106 into the bone microenvironment10. In 2009, Yu et al.11 established a reproducible orthotopic femur OS rat model using UMR106 cells in larger male SD rats. The successful tumor implantations and lung metastasis rate in rats without amputation were similar to the data presented here. In this study, an added amputation to the model using young rats was performed, which suggested that the timing of primary tumor removal is crucial in modeling OS, especially related to metastatic progression. With this refinement, amputation and in vivo imaging improve this model for pre-clinical studies for novel drug assessment for OS.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>AKT</td>
			<td>Cell Signaling TECHNOLOGY</td>
			<td>4685S</td>
			<td></td>
		</tr>
		<tr>
			<td>absorbable suture</td>
			<td>Ethicon</td>
			<td>J214H</td>
			<td></td>
		</tr>
		<tr>
			<td>&#946;-actin</td>
			<td>SANTA CRUZ BIOTECHNOLOGY</td>
			<td>sc-47778</td>
			<td></td>
		</tr>
		<tr>
			<td>&#946;2-AR antibody</td>
			<td>SANTA CRUZ BIOTECHNOLOGY</td>
			<td>sc-569</td>
			<td>replaced by &#946;2-AR (E-3): sc-271322</td>
		</tr>
		<tr>
			<td>Bis&#8211;Tris gels</td>
			<td>Thermo Fisher</td>
			<td>NP0321PK2</td>
			<td></td>
		</tr>
		<tr>
			<td>Buprenorphine SR Lab</td>
			<td>ZooPharm</td>
			<td>IZ-70000-201908</td>
			<td></td>
		</tr>
		<tr>
			<td>CD3 antibody</td>
			<td>Dako</td>
			<td>#A0452</td>
			<td></td>
		</tr>
		<tr>
			<td>CD68 antibody</td>
			<td>eBioscience</td>
			<td>#14-0688-82</td>
			<td></td>
		</tr>
		<tr>
			<td>Chemiluminescent substrate</td>
			<td>cytiva</td>
			<td>RPN2232</td>
			<td></td>
		</tr>
		<tr>
			<td>CL-Xposure film</td>
			<td>Thermo Fisher</td>
			<td>34089</td>
			<td></td>
		</tr>
		<tr>
			<td>Complete Anesthesia System</td>
			<td>EVETEQUIP</td>
			<td>922120</td>
			<td></td>
		</tr>
		<tr>
			<td>diaminobenzidine</td>
			<td>VECTOR LABORATORIES</td>
			<td>SK-4100</td>
			<td></td>
		</tr>
		<tr>
			<td>Doxorubicin</td>
			<td>Actavis</td>
			<td>NDC 45963-733-60</td>
			<td></td>
		</tr>
		<tr>
			<td>EGFR antibody</td>
			<td>SANTA CRUZ BIOTECHNOLOGY</td>
			<td>sc-03</td>
			<td>replaced by EGFR (A-10): sc-373746</td>
		</tr>
		<tr>
			<td>ERBB2 antibody</td>
			<td>SANTA CRUZ BIOTECHNOLOGY</td>
			<td>sc-284</td>
			<td>replaced by Neu (3B5): sc-33684</td>
		</tr>
		<tr>
			<td>ERBB4 antibody</td>
			<td>SANTA CRUZ BIOTECHNOLOGY</td>
			<td>sc-283</td>
			<td>replaced by ErbB4 (C-7): sc-8050</td>
		</tr>
		<tr>
			<td>ERK antibody</td>
			<td>SANTA CRUZ BIOTECHNOLOGY</td>
			<td>sc-514302</td>
			<td></td>
		</tr>
		<tr>
			<td>eye lubricant</td>
			<td>PHARMADERM</td>
			<td>NDC 0462-0211-38</td>
			<td></td>
		</tr>
		<tr>
			<td>Hamilton syringe (100 &#181;L)</td>
			<td>Hamilton</td>
			<td>Model 1710 SN SYR</td>
			<td></td>
		</tr>
		<tr>
			<td>horseradish peroxidase-linked secondary antibody</td>
			<td>cytiva</td>
			<td>NA934</td>
			<td></td>
		</tr>
		<tr>
			<td>HRP polymer detection kit</td>
			<td>VECTOR LABORATORIES</td>
			<td>MP-7401</td>
			<td></td>
		</tr>
		<tr>
			<td>HRP polymer detection kit</td>
			<td>VECTOR LABORATORIES</td>
			<td>MP-7402</td>
			<td></td>
		</tr>
		<tr>
			<td>isoflurane</td>
			<td>BUTLER SCHEIN</td>
			<td>NDC 11695-6776-2</td>
			<td></td>
		</tr>
		<tr>
			<td>isoflurane vaporizer</td>
			<td>EVETEQUIP</td>
			<td>911103</td>
			<td></td>
		</tr>
		<tr>
			<td>UMR-106 cell</td>
			<td>ATCC</td>
			<td>CRL-1661</td>
			<td></td>
		</tr>
		<tr>
			<td>X-ray</td>
			<td>Faxitron</td>
			<td>UltraFocus</td>
			<td></td>
		</tr>
		<tr>
			<td>X-ray processor</td>
			<td>Hope X-Ray Peoducts Inc</td>
			<td>MicroMax X-ray Processor</td>
			<td>Hope Processors are not available in USA anymore</td>
		</tr>
		<tr>
			<td>wound clips</td>
			<td>BECTON DICKINSON</td>
			<td>427631</td>
			<td></td>
		</tr>
	</tbody>
</table>

a syngeneic orthotopic osteosarcoma sprague dawley rat model with amputation to control metastasis rate

The most recent advance in the treatment of osteosarcoma (OS) occurred in the 1980s when multi-agent chemotherapy was shown to improve overall survival compared to surgery alone. To address this problem, the aim of the study is to refine a lesser-known model of OS in rats with a comprehensive histologic, imaging, biologic, implantation, and amputation surgical approach that prolongs survival. We used an immunocompetent, outbred Sprague-Dawley (SD), syngeneic rat model with implanted UMR106 OS cell line (originating from a SD rat) with orthotopic tibial tumor implants into 3-week-old male and female rats to model pediatric OS. We found that rats develop reproducible primary and metastatic pulmonary tumors, and that limb amputations at 3 weeks post implantation significantly reduce the incidence of pulmonary metastasis and prevent unexpected deaths. Histologically, the primary and metastatic OSs in rats were very similar to human OS. Using immunohistochemistry methods, the study shows that rat OS are infiltrated with macrophages and T cells. A protein expression survey of OS cells reveals that these tumors express ErbB family kinases. Since these kinases are also highly expressed in most human OSs, this rat model could be used to test ErbB pathway inhibitors for therapy.

Immunocompetent SD outbred rats are used for these OS studies, which offers an animal model with an intact immune system. We have used the UMR106 cell line from ATCC, developed from cells that were initially isolated from an OS from a SD rat. We implanted the cells into SD rats, thus providing a syngeneic model for OS. UMR106 cells are implanted into the tibia of 3-week-old male and female SD rats, simulating a pediatric OS model. Moreover, the orthotopic implantation of UMR106 cells directly into the tibia metaphysis/di...

Watch this Scientific Journal Video about A Syngeneic Orthotopic Osteosarcoma Sprague Dawley Rat Model with Amputation to Control Metastasis Rate at JoVE.com

A Syngeneic Orthotopic Osteosarcoma Sprague Dawley Rat Model with Amputation to Control Metastasis Rate

Here, a syngeneic orthotopic implantation followed by an amputation procedure of the osteosarcoma with spontaneous pulmonary metastasis that can be used for preclinical investigation of metastasis biology and development of novel therapeutics is described.

The most recent advance in the treatment of osteosarcoma (OS) occurred in the 1980s when multi-agent chemotherapy was shown to improve overall survival ...

Implanting osteosarcoma cells inside the tibia microenvironment promotes lung metastasis. This model can also be useful for studying the mechanisms of pulmonary metastasis or novel cancer therapies that require an intact immune system. Once the tumor has been established, amputation is necessary to control the rate of metastasis in long-term survival studies.We use the jugular injections to allow the visualization of intravenous drug delivery. Jugular vein injection is useful for many other disease models for which a precise drug delivery is required. We have used this method to deliver nanoparticles and radiolabeled ligans for in-vivo imaging.We advise new users to practice removing a limb from five to 10 euthanized rats before attempting an experiment to master the mechanics of limb amputation without blood loss. After confirming a lack of response to penile reflex, secure the anesthetized rat in a nosecone on a low-heat setting heat pad in the supine position. Remove the hair on the right leg, up to the ventral and dorsal lower abdomen.Use gauze or spray to disinfect the surgical area with 70%ethanol and an appropriate diluted antiseptic and apply ointment to the animal's eyes. Using a drill-like motion to make an opening, insert a 22-gauge needle marked 10 millimeters from the tip 10 millimeters into the diaphysis of the tibia in the middle of the tibial plateau, extending the needle through the metaphysis into the diaphysis. After removing the needle, gently mix the tumor cell suspension of interest to obtain a homogenous cell suspension, and load 7.5 x 10 to the fourth of the cells in 20 microliters of PBS into a Hamilton syringe.Mark the Hamilton syringe with cells 10 millimeters from the needle tip and insert the needle to the 10 millimeter mark into the hole made by the 22-gauge needle. Then gently discharge the entire volume of cells into the marrow cavity, and place the rat into a cage on a heating pad with monitoring until full recumbency. For intravenous doxorubicin administration, after anesthesia confirmation, use careful dissection to visualize the right or left jugular vein, and insert the needle into the overlying muscle tissue.Direct the needle toward the head into the jugular vein lumen, as it is visualized in the jugular vein anterior to the pectoralis muscle, and draw a small volume of blood into the needle tip to confirm an accurate insertion. When the needle is in place, slowly inject 100 to 150 microliters of two milligram per kilogram doxorubicin over one minute. The solution should be visible within the vein during the delivery.When all of the solution has been delivered, use sterile gauze to apply gentle pressure to the vein, and use three to four wound clips to close the incision. After confirming sedation, remove the hair on the right leg, up to the ventral and the dorsal lower abdomen, and place the rat in the supine position on a heating pad. Scrub the skin from the middle of the calf to just above the hip joint of the right lower abdomen as demonstrated and apply ointment to the animal's eyes.Using sterile gloves and instruments, pull the leg through the vent of the sterile surgical drape and make a circumferential cutaneous incision just proximal to the stifle. Deglove the hind limb to expose the femoral artery and vein on the ventral-medial surface of the hind limb, and use 4-0 absorbable sutures to litigate the vessels at the level of the mid-femur and transect distally. Clamp the vein distally to reduce leakage during muscle dissection and use blunt dissection to abduct the hip joint with lateral outward rotation.Locate and disarticulate the head of the femur from the acetabulum, and remove any remaining tissue, keeping the leg attached to the body. Administer a splash block to the acetabulum and sciatic nerve with approximately six milligrams per kilogram of ropivacaine, and use a simple interrupted 4-0 absorbable suture to close the musculature over the acetabulum. Then use wound clips placed five to 10 millimeters to close the edges of the skin.X-ray imaging for tumor surveillance allows the confirmation of bone tumor invasion and can be performed on recently-amputated or formalin-fixed limbs. X-ray imaging also permits evaluation of the radiographic morphology of the lungs with and without metastases, providing a quick and easy method for determining the need for euthanasia to prevent unnecessary spontaneous deaths. In the rat osteosarcoma, both osteolytic and osteoblastic tumor morphology can be confirmed by histopathology of the amputated limb.Note that the cortical bone is absent in this example and that the adjacent bone has been replaced with or fortified by new woven bone that is oriented perpendicular to the existing shaft of the cortex. Islands of immature osteoids can also be identified within the tumor. In these images, the microscopic morphology of representative lung metastases, some with mineralized bone and tumor vascular emboli can be observed.Immunostaining of primary osteosarcoma tumors can reveal infiltration of the tumors by immune cell populations, such as CD68-positive macrophages or CD3-positive T-cells. Western blotting of tumor cell protein lysates can be used to determine the expression of protein kinases, protein kinase receptors, and other proteins that interact with these pathways. For tibial implantation, once the first tibial hole has been made, continue to hold the leg in your non-dominant hand at the same angle to keep the skin and the bone holes lined up to make the Hamilton needle insertion easier.For jugular injection, insert the needle into the muscle, but do not angle the needle too much to avoid missing the vein. For the amputation, practice the disarticulation on euthanized rats first.

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3.4K 조회수.  The Johns Hopkins University School of Medicine. 경골 미세 환경 내부에 골육종 세포를 이식하는 것은 폐 전이를 촉진합니다. 이 모형은 또한 그대로 면역 계통을 요구하는 폐 전이 또는 새로운 암 치료의 기계장치를 공부하기 위하여 유용할 수 있습니다. 일단 종양이 설치되면, 절단은 장기 생존 연구에서 전이의 비율을 통제하기 위하여 필요합니다.우리는 정맥 약물 전달의 시각화를 허용하기 위해 경정맥 주사를 사?...