NIH 보조금 P30의 CA051008 및 CA009686 T32 (ATR)에 의해 지원됩니다.

타원체의 1 세대 <ol><li> PBS를 사용하여 70 %의 합류 ~의 부착 암 세포 배양을 분리하여 드롭 문화를 걸려 위해 단일 ​​세포 현탁액을 준비 0.05 % 트립신 EDTA 용액에 노출 된 다음에 씻으십시오. <ol><li> 세포 배양 배지와 트립신 용액을 중화하고 세포 현탁액의 분취 량을 사용하여 세포를 카운트. 주 : 세포주에 달려 특정 세포 배양 배지는 테스트중인. 세포 배양 배지는 일반적으로 DMEM + 10 % FBS이고, ATCC 미디어 권장 사항을 따르십시오. 자세한 내용은 표 재료에서 찾을 수있다. </li><li> 세포 배양 배지를 20 μL 방울 당 500 ~ 1,000 세포 시딩 있도록 희석을 수행한다. </li></ol></li><li> 10cm 접시를 취득하고 아래로 멸균 PBS의 5 mL를 추가 할 수 있습니다. 참고 :이 단계는 교수형이 증발에서 떨어 보호합니다. 저비용 &quot;세균 등급&quot;요리, 세포 배양 등급 요리 대신에 사용될 수있는 바와 같이, 세포를 계속하지 않을 것이다문화 표면 역할을합니다. </li><li> 뚜껑의 내면에 희석 된 세포 현탁액 20 μL 방울을 전송하는 멀티 채널 피펫을 사용한다. <ol><li> 피펫 (40)는 10cm 접시의 뚜껑에 (8 방울의 5 행)을 삭제합니다. </li></ol></li><li> 배양 접시 위에 뚜껑과 장소를 반전. 스페 로이드를 생성하기 위해 72 시간 동안 37 ℃에서 배양 매달려 드롭 부화. <ol><li> 자신감, 아직 통제 된 방식으로 뚜껑을 뒤집습니다. 참고 : 너무 빠르거나 너무 느린 뚜껑을 반전하면 물방울이 이동하는 원인이 될 수 있습니다. 다른 소형 응집체를 생성하기 위해 72 개 이상의 시간을 요구할 수 있지만 어떤 세포주는 48 시간 이내에 구 상체를 형성 할 수있다. </li></ol></li></ol> 3D 매트릭스에 타원체 2. 임베딩 <ol><li> 밤새 스페 로이드를 매립하기 전에 4 ℃에서 성장 인자 - 감소 된 기저막 물질의 분취 량을 해동. <ol><li> 옵션 : 사전에 ECM와 레이어 우물은 조직 cultu 잠재적 회전 타원체의 상호 작용을 방지하기 위해표면 재. <ol><li> 24 웰 플레이트에 웰 당 ECM의 피펫 200 μL. </li><li> ECM은 전체 잘 표면을 커버하도록 판을 기울. </li><li> 조심스럽게 피펫으로 초과 ECM을 제거합니다. </li><li> 3 시간 실온에서 또는 4 박 ° C에서 : 우물이 건조 될 때까지 판을 품어. </li></ol></li></ol></li><li> 조직 배양 접시의 뚜껑을 틸팅 및 미디어를 풀링하여 타원체를 수집한다. 1.5 ml의 microcentrifuge 관에 회전 타원체와 미디어를 전송합니다. </li><li> 타원체가 microcentrifuge 관의 바닥에 정착하는 10 분을 허용합니다. 타원체는 눈으로 볼 수 있어야합니다. </li><li> . 감기 (4 ° C를) 100 ㎕ 내가 별도의 사전 냉각 튜브에 콜라겐 유형의 기저막 재료의 100 μl를 혼합 조기 응고에서 중 젤을 방지하기 위해 4 ° C에서 혼합물을 유지합니다. <ol><li> 작은 볼륨을 전송하는 경우 사전 냉장 피펫 팁을 사용합니다. </li><li> 때주의를 줘I가 기포 형성을 방지하기 기저막 재료 및 콜라겐 형 혼합. 주 :이 겔에 매립 될 경우 기포 프로토콜 뒷부분 이미징을 방해 할 수있다. </li></ol></li><li> microcentrifuge 관의 40 μL 바닥 부분에서 타원체를 대기음, 나는 혼합물을 콜라겐 기저막 재료 / 유형과 결합. 혼합 할 때 기포 형성을 방지하기 위해주의해야합니다. 주 : 용액 100 μL 콜라겐 유형 I 및 타원체 40 μL 4 3D 배양 독립적 충분한 물질을 생성, 100 μL 기저막 재료 함유. 이 스케일 업 또는 다운 할 수 있습니다. </li><li> 피펫 24 웰 플레이트에 웰의 중심에 점성 혼합물의 40 μl를 삭제합니다. 웰의 측면에 실행 혼합을 방지하기 위해 플레이트를 수평으로 유지. 참고 : 24 웰 플레이트에 하나의 열 - 4 웰 - 각 조건 테스트 할 것을 권장합니다. </li><li> 판 INT 배치OA 37 ° C 배양기에서 30 분 동안 그대로 둡니다. 3D 문화는이 기간 동안 중합합니다. </li><li> 서서히 세포 배양 배지 1 ㎖로 3 차원 배양 잠수함. <ol><li> 또한 겔 중합을 촉진하기 위해 우물에 그것을 추가 할 때 미디어가 따뜻한 있는지 확인합니다. </li><li> 중요한 단계 : 부드럽게 3D 문화에 미디어를 추가 할 수 있습니다. 우물에 너무 빨리 미디어를 피펫은 조직 배양 표면에서 3D 문화의 분리로 이어질 수 있습니다. </li></ol></li></ol> 3. 모니터링 및 회전 타원체 침공 분석 <ol><li> 연구자에 의해 결정 시간 지점에서 주변의 3D 매트릭스로 회전 타원체에서 이미지 침공. 20 배 대물 렌즈와 거꾸로 현미경을 사용하여 사진을 획득. 주의 : 이상적 시간 - 포인트는 테스트되는 세포주에 따라 다를 것이다. 더 침습적 세포주는 곧 도금 후 타원체에서 자신의 출구를 시작하고, 따라서, 초기 사진을 취할 것입니다도금 후 몇 시간 이내의. 일반적으로, 사진은 (도금 후) 0 시간, 24 시간, 48 시간에서 가져옵니다. 침략은 일반적으로 도금 후 24 시간 내지 48을 마칩니다. </li><li> 이미지 J. 같은 영상 분석 소프트웨어를 사용하여 침입 능력을 정량 <ol><li> 회전 타원체의 가장자리에서 셀 거리로 침략을 분석합니다. <ol><li> 반경 및 / 또는 최대 침략 거리를 표시하기 위해 직선 그리기 도구를 사용합니다. </li><li> 길이 측정을 표시하는 &quot;측정&quot;을 상단 메뉴의 &quot;분석&quot;을 선택한 후 클릭합니다. </li></ol></li><li> 회전 타원체 외부 총 침략 영역으로 침략을 분석합니다. <ol><li> 회전 타원체 및 / 또는 총 침략 영역의 경계를 추적 자유형 그리기 도구를 사용합니다. </li><li> 지역 측정을 표시하는 &quot;측정&quot;을 상단 메뉴의 &quot;분석&quot;을 선택한 후 클릭합니다. </li></ol></li><li> 이미지의 스택에 대한 측정을 만드는 데 투자 수익 (ROI) 관리자 도구와 같은 플러그인을 사용합니다. </li></ol>
	</li>
</ol>

<ol>
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The authors declare that they have no competing financial interests.

본 연구는 회전 타원체 침윤 분석 (표 1) 암 세포주 패널의 성능을 평가 하였다. 일반적으로, 우리는 회전 타원체 형성 세포 간 접합이 존재 타원체 형상 구조의 형성을 촉진 더 상피 생긴 세포주에서 향상되는 것을 발견한다. MDA-MB-231 세포와 같은 상피 - 간엽 전환을받은 알려진 세포주, 그들의 감소 E-, N- 및 P-cadherin의 발현 16에 가장 가능성이 매달려 드롭 문화 타원체를 형성?...

그것은 암 세포의 운동성이 같은 행동이 순환 시스템 1에 기저막과 항목을 통해 침입을 용이하게 주어진, 전이 가능성의 예측이라고 설정됩니다. 운동성에 가장 연구가 광범위하게 3 차원 매트릭스에서 세포의 이동 것 실제로 방법이 동일 세포보다 대표 인 것으로 인식되고있다하더라도 세포가, 2 차원 (2D) 환경에서 동작하는 방법에 초점을 맞추었다 생체 2에서 작동합니다. 3 차원 배양 시스템은 점차 성장 역학 및 약물 감수성 3, 세포 형태의 범위 셀룰러 동작을 연구하기 위해 사용된다. 3 차원 환경의 컨텍스트 내에서 암 세포 침입을 모니터링하는 욕구는 3 차원 세포 내로 이러한 타원체 매립 하였다 매달려 드롭 배양법 (4)를 통해 3 차원 세포 집합체 (타원체)의 생성을 포함하는 이전에 확립 된 기술을 합성하게되었다 매트릭스 (ECM) 콜라겐과 기저막 재료 (5)으로 구성. 이 방법은 쉽게 실험 다양한 조건 하에서 내습과 비교하기 위해 이용 될 수있는 간소화 된 방법을 제공함으로써 이전에 확립 된 기술을 개선하고자한다. 체외에서 세포 운동성을 평가하는 전통적인 방법은 스크래치 상처 분석 및 트랜스 웰 분석 (6)이다. 전 분석은 2 차원 환경에서 세포 운동성을 도시 한 생체 침입에 중요한 다양한 기능, 예를 들면 프로테아제 활성 7 그러므로 독립적이다. 트랜스 웰 분석은 웰 인서트가 대향 막 표면에 세포의 모양, 즉 ECM 기재하지만, 단 하나의 파라미터를 더 모델 세포 침윤 코팅 할 수있을 때를 측정하고, 세포 침윤의 많은 뉘앙스 따라서 용이하게 관찰 할 수없는된다. 이러한 기술, 암세포 침윤 타원체 분석 (도 1 &lt;대조적/ 강해&gt;) 만 생리 관련이없는 환경에서 세포 침윤의 실시간 모니터링을 허용하지만, 또한 이러한 집단 대 개인 세포 이동 8로서 가시화 될 중요한 세포주 특정 기능을 허용한다. 이 방법은 표준 3 차원 배양 성장 분석보다 이점을 제공한다. 세포는 이러한 제한이 해제 된 후 침입하는 인센티브되도록 매달려 드롭 방법을 통해 세포 응집체의 생성은 처음에 세포의 움직임을 제한한다. 그 제약 조건이 해제되면 또한, 세포 출구는 편리하게 정량 할 수있는 일정한 방향으로 진행됩니다. 암세포 타원체 분석법에 가장 널리 사용되는 재료는 ECM의 Matrigel하고 이러한 구성 요소들의 각각은 전이 거동에 영향을 미치는 중요한 역할과 구별 갖는 경우 타입 I 콜라겐. 마트 리겔은 Engelbreth-Holm이 운집 마우스 육종 세포에 의해 생산 된 단백질의 분비 혼합물이며, baseme에 충실이러한 라미닌, entactin 및 제 4 형 콜라겐 (9)와 같은 NT를 막 단백질. 이 때문에 마트 리겔은 이제부터라고 &quot;기저막 물질.&quot;이 기저막 물질은 세포의 행동 (11) 상에 다양한 효과를 발휘하는 다른 많은 단백질 외에 암세포 침윤 (10) 중 접착 인테그린에 필요한 필수적인 리간드를 제공한다. 비교하면, 일반적으로 힘줄 등 치밀한 콜라겐 구조 (12)의 산으로부터 제조 다이제스트 I 형 콜라겐은, 본체의 결합 조직과 기질지지 조직과 기관의 주요 구조적 요소로서 기능 훨씬 단순 매트릭스 물질이다. 이것은 콜라겐의 물리적 특성은 세포 운동성의 기능의 수를 조절할 수 있음을 입증되었다; 예를 들어, 종양 - 기질 계면에서 콜라겐 섬유의 배향은 기질 (13)에 침입 할 때 그 다음에 피 브릴을 따라 이동하는 암세포를 허용. 여기에 제시된 분석에서는 두 종류의 난 콜라겐과 기저막 재료는 3D 암 세포 - 기질 상호 작용을 연구하는 도구로 사용된다. 세포를 3 차원 매트릭스에 매립 한 후 침입이 모니터링 될 수 제어 경로의 억제 또는 자극의 효과. 세포 매달려 방울 또는 긴 치료가 침공을 조절해야합니다 여부에 따라 3D 문화로 전송시 성장하는 동안 전처리 할 수​​ 있습니다. 짧은 치료를 들어, 약물이 컬렉션 후 타원체 서스펜션뿐만 아니라 셀에 충분한 약물 노출을 용이하게하기 위해, 3 차원 배양을 둘러싸 매체와 혼합하는 것을 추천합니다. 다음에, 정상 또는 종양 - 관련 기질 세포는 종양 세포의 침윤을 변조에서의 역할을 평가하는 방법 또는자가 분비 및 주변 분비 신호의 영향 세포 행동 결정하는 매트릭스 물질과 혼합 될 수있다. 이 아이디어는 연구에 나타내었다 곳 (COL)의 공 배양암 매달려 방울의 내피 세포에 회전 타원체 (14) 내의 혈관 네트워크되었다. 암세포 침윤이 다른 기판 (15)에 의해 영향을 마지막으로, ECM 성분은 또한 변경 될 수있다. 아래에 제시된 방법에 따라서 다양한 조건 하에서 암 세포의 침윤을 평가하기위한 프레임 워크를 제공한다. 일반적으로 모든 세포주가 걸려 방울에 타원체를 생성하고 상피 보이는 세포주는 일반적으로 일반 구를 형성하지 않는 것이 발견되었다.

<table>
	<tbody>
		<tr>
			<td>Matrigel Growth Factor Reduced</td>
			<td>Corning</td>
			<td>CB-40234</td>
			<td></td>
		</tr>
		<tr>
			<td>Collagen Type I, Rat Tail, 100 mg</td>
			<td>Millipore</td>
			<td>08-115</td>
			<td></td>
		</tr>
		<tr>
			<td>DMEM</td>
			<td>Life Technologies</td>
			<td>11995-065</td>
			<td></td>
		</tr>
		<tr>
			<td>RPMI 1640 Medium&#160;</td>
			<td>Life Technologies</td>
			<td>11875-093</td>
			<td></td>
		</tr>
		<tr>
			<td>PBS</td>
			<td>Life Technologies</td>
			<td>10010-023</td>
			<td></td>
		</tr>
		<tr>
			<td>0.05% Trypsin-EDTA</td>
			<td>Life Technologies</td>
			<td>25300-054</td>
			<td></td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum, Heat Inactivated</td>
			<td>Omega Scientific</td>
			<td>FB-12</td>
			<td></td>
		</tr>
		<tr>
			<td>100mm TC-treated Dishes</td>
			<td>Corning Incorporated</td>
			<td>430167</td>
			<td></td>
		</tr>
		<tr>
			<td>24-well TC-treated Plates</td>
			<td>NEST Biotechnlology</td>
			<td>702001</td>
			<td></td>
		</tr>
		<tr>
			<td>Olympus IX-71 Inverted Microscope</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td colspan="4">Cell lines were maintained in DMEM + 10% FBS, with the expection of BT-474 and LNCaP cells, which were mantained in RPMI + 10% FBS.</td>
		</tr>
	</tbody>
</table>

a cancer cell spheroid assay to assess invasion in a 3d setting

The invasive nature of cancer cell lines is thought to correlate with their metastatic potential. Most traditional assays, however, do not examine these invasive features in a three-dimensional environment and the resulting data suffer from reduced biological applicability. Here an approach is presented to visualize the invasive ability of cell lines in a physiologically relevant setting. The cancer cell spheroid invasion assay first utilizes gravity to generate spheroids within drops of media that hang from the lid of a cell culture dish. Next, these spheroids are embedded in a 3D matrix consisting of a mixture of basement membrane materials and type I collagen. Cancer cell egression from the spheroids into the surrounding matrix is then monitored over time. The method described here can be modified to examine invasion after coculture of different cell types, inclusion of drugs/inhibitors, or alterations in extracellular matrix (ECM) constituents.

회전 타원체 침입 분석을 이용하여 (도 1), 암 세포주의 패널뿐만 아니라, 기저막 재료 및 타입 I 콜라겐으로 이루어진 3 차원 매트릭스로 주입 후에 나타나는 셀 출구의 양 구 상체를 형성하는 능력에 대해 시험 하였다 (표 1). 이 결과는 모든 암 세포주가 시험 관내 상피 형태를 갖는 세포주 정규 매끄러운 골재를 생산하는 경향이 잘 형성된 타원체를 생성 함을 입증...

Watch this Scientific Journal Video about A Cancer Cell Spheroid Assay to Assess Invasion in a 3D Setting at JoVE.com

A Cancer Cell Spheroid Assay to Assess Invasion in a 3D Setting

This method evaluates cancer cell invasion from spheroids into a surrounding 3D matrix. Spheroids are generated via the hanging drop culture method and then embedded in a matrix comprised of basement membrane materials and type I collagen. Invasion out of the spheroids is subsequently monitored.

암 세포 회전 타원체 분석은 3D 설정에 침략을 평가하기 위해

The invasive nature of cancer cell lines is thought to correlate with their metastatic potential.  Most traditional assays, however, do not examine these ...

a-cancer-cell-spheroid-assay-to-assess-invasion-in-a-3d-setting

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JoVE Journal

Medicine

32.3K 조회수.  Georgetown University. This method evaluates cancer cell invasion from spheroids into a surrounding 3D matrix. Spheroids are generated via the hanging drop culture method and then embedded in a matrix comprised of basement membrane materials and type I collagen. Invasion out of the spheroids is subsequently monitored. 

비디오: A Cancer Cell Spheroid Assay to Assess Invasion in a 3D Setting

A Real-time Electrical Impedance Based Technique to Measure Invasion of Endothelial Cell Monolayer by Cancer Cells

Metastatic dissemination of malignant cells requires degradation of basement membrane, attachment of tumor cells to vascular endothelium, retraction of endothelial junctions and finally invasion and migration of tumor cells through the endothelial layer to enter the bloodstream as a means of transport to distant sites in the host1-3. Once in the circulatory system, cancer cells adhere to capillary walls and extravasate to the surrounding tissue to form metastatic tumors4,5. The various components of tumor cell-endothelial cell interaction can be replicated in vitro by challenging a monolayer of human umbilical vein endothelial cells (HUVEC) with cancer cells. Studies performed with electron and phase-contrast microscopy suggest that the in vitro sequence of events fairly represent the in vivo metastatic process6. Here, we describe an electrical-impedance based technique that monitors and quantifies in real-time the invasion of endothelial cells by malignant tumor cells.
Giaever and Keese first described a technique for measuring fluctuations in impedance when a population of cells grow on the surface of electrodes7,8. The xCELLigence instrument, manufactured by Roche, utilizes a similar technique to measure changes in electrical impedance as cells attach and spread in a culture dish covered with a gold microelectrode array that covers approximately 80% of the area on the bottom of a well. As cells attach and spread on the electrode surface, it leads to an increase in electrical impedance9-12. The impedance is displayed as a dimensionless parameter termed cell-index, which is directly proportional to the total area of tissue-culture well that is covered by cells. Hence, the cell-index can be used to monitor cell adhesion, spreading, morphology and cell density.
The invasion assay described in this article is based on changes in electrical impedance at the electrode/cell interphase, as a population of malignant cells invade through a HUVEC monolayer (Figure 1). The disruption of endothelial junctions, retraction of endothelial monolayer and replacement by tumor cells lead to large changes in impedance. These changes directly correlate with the invasive capacity of tumor cells, i.e., invasion by highly aggressive cells lead to large changes in cell impedance and vice versa. This technique provides a two-fold advantage over existing methods of measuring invasion, such as boyden chamber and matrigel assays: 1) the endothelial cell-tumor cell interaction more closely mimics the in vivo process, and 2) the data is obtained in real-time and is more easily quantifiable, as opposed to end-point analysis for other methods.

This article describes an in vitro technique for monitoring cancer cells invading through a monolayer of endothelial cells. The data is acquired in real-time as a function of changes in impedance on the surface of electrodes at the well bottom.

암 세포에 의해 내피 세포 단층의 침략을 측정하는 실시간 전기 임피던스 기반 기술

Metastatic dissemination of malignant cells requires degradation of basement membrane, attachment of tumor cells to vascular endothelium, retraction of ...

연구

의학

Multi-photon Imaging of Tumor Cell Invasion in an Orthotopic Mouse Model of Oral Squamous Cell Carcinoma

Loco-regional invasion of head and neck cancer is linked to metastatic risk and presents a difficult challenge in designing and implementing patient management strategies. Orthotopic mouse models of oral cancer have been developed to facilitate the study of factors that impact invasion and serve as model system for evaluating anti-tumor therapeutics. In these systems, visualization of disseminated tumor cells within oral cavity tissues has typically been conducted by either conventional histology or with in vivo bioluminescent methods. A primary drawback of these techniques is the inherent inability to accurately visualize and quantify early tumor cell invasion arising from the primary site in three dimensions. Here we describe a protocol that combines an established model for squamous cell carcinoma of the tongue (SCOT) with two-photon imaging to allow multi-vectorial visualization of lingual tumor spread. The OSC-19 head and neck tumor cell line was stably engineered to express the F-actin binding peptide LifeAct fused to the mCherry fluorescent protein (LifeAct-mCherry). Fox1nu/nu mice injected with these cells reliably form tumors that allow the tongue to be visualized by ex-vivo application of two-photon microscopy. This technique allows for the orthotopic visualization of the tumor mass and locally invading cells in excised tongues without disruption of the regional tumor microenvironment. In addition, this system allows for the quantification of tumor cell invasion by calculating distances that invaded cells move from the primary tumor site. Overall this procedure provides an enhanced model system for analyzing factors that contribute to SCOT invasion and therapeutic treatments tailored to prevent local invasion and distant metastatic spread. This method also has the potential to be ultimately combined with other imaging modalities in an in vivo setting.

A comprehensive overview of the techniques involved in generating a mouse model of oral cancer and quantitative monitoring of tumor invasion within the tongue through multi-photon microscopy of labeled cells is presented. This system can serve as a useful platform for the molecular assessment and drug efficacy of anti-invasive compounds.

구강 편평 세포 암종의 Orthotopic 마우스 모델에서 종양 세포 침략의 다중 광자 이미징

Loco-regional invasion of head and neck cancer is linked to metastatic risk and presents a difficult challenge in designing and implementing patient ...

Spheroid Assay to Measure TGF-&#946;-induced Invasion

TGF-&beta; has opposing roles in breast cancer progression by acting as a tumor suppressor in the initial phase, but stimulating invasion and metastasis at later stage1,2. Moreover, TGF-&beta; is frequently overexpressed in breast cancer and its expression correlates with poor prognosis and metastasis 3,4. The mechanisms by which TGF-&beta; induces invasion are not well understood.
TGF-&beta; elicits its cellular responses via TGF-&beta; type II (T&beta;RII) and type I (T&beta;RI) receptors. Upon TGF-&beta;-induced heteromeric complex formation, T&beta;RII phosphorylates the T&beta;RI. The activated T&beta;RI initiates its intracellular canonical signaling pathway by phosphorylating receptor Smads (R-Smads), i.e. Smad2 and Smad3. These activated R-Smads form heteromeric complexes with Smad4, which accumulate in the nucleus and regulate the transcription of target genes5. In addition to the previously described Smad pathway, receptor activation results in activation of several other non-Smad signaling pathways, for example Mitogen Activated Protein Kinase (MAPK) pathways6.
To study the role of TGF-&beta; in different stages of breast cancer, we made use of the MCF10A cell system. This system consists of spontaneously immortalized MCF10A1 (M1) breast epithelial cells7, the H-RAS transformed M1-derivative MCF10AneoT (M2), which produces premalignant lesions in mice8, and the M2-derivative MCF10CA1a (M4), which was established from M2 xenografts and forms high grade carcinomas with the ability to metastasize to the lung9. This MCF10A series offers the possibility to study the responses of cells with different grades of malignancy that are not biased by a different genetic background.
For the analysis of TGF-&beta;-induced invasion, we generated homotypic MCF10A spheroid cell cultures embedded in a 3D collagen matrix in vitro (Fig 1). Such models closely resemble human tumors in vivo by establishing a gradient of oxygen and nutrients, resulting in active and invasive cells on the outside and quiescent or even necrotic cells in the inside of the spheroid10. Spheroid based assays have also been shown to better recapitulate drug resistance than monolayer cultures11. This MCF10 3D model system allowed us to investigate the impact of TGF-&beta; signaling on the invasive properties of breast cells in different stages of malignancy.

Spheroid Assay to Measure TGF-&amp;#946;-induced Invasion

An assay to quantitatively measure Transforming Growth Factor (TGF)-&#x03B2;-induced invasion in 3-dimensional collagen gels is described. This assay takes advantage of the MCF10A series of cell lines, which represent different stages of breast cancer development. This method can be adopted to be used with other cell lines and might be used to investigate other potential activators or inhibitors of invasion.

TGF - β - 유발 침략을 측정하는 회전 타원체 분석

TGF-&beta; has opposing roles in breast cancer progression by acting as a tumor suppressor in the initial phase, but stimulating invasion and metastasis ...

Modeling and Imaging 3-Dimensional Collective Cell Invasion

A defining characteristic of cancer malignancy is invasion and metastasis 1. In some cancers (e.g. glioma 2), local invasion into surrounding healthy tissue is the root cause of disease and death. For other cancers (e.g. breast, lung, etc.), it is the process of metastasis, in which tumor cells move from a primary tumor mass, colonize distal sites and ultimately contribute to organ failure, that eventually leads to morbidity and mortality 3. It has been estimated that invasion and metastasis are responsible for 90&#37; of cancer deaths 4. As a result, there has been intense interest in identifying the molecular processes and critical protein mediators of invasion and metastasis for the purposes of improving diagnosis and treatment 5.
A challenge for cancer scientists is to develop invasion assays that sufficiently resemble the in vivo situation to enable accurate disease modeling 6. Two-dimensional cell motility assays are only informative about one aspect of invasion and do not take into account extracellular matrix (ECM) protein remodeling which is also a critical element. Recently, research has refined our understanding of tumor cell invasion and revealed that individual cells may move by elongated or rounded modes 7. In addition, there has been greater appreciation of the contribution of collective invasion, in which cells invade in strands, sheets and clusters, particularly in highly differentiated tumors that maintain epithelial characteristics, to the spread of cancer 8.
We present a refined method 9 for examining the contributions of candidate proteins to collective invasion 10. In particular, by engineering separate pools of cells to express different fluorescent proteins, it is possible to molecularly dissect the activities and proteins required in leading cells versus those required in following cells. The use of RNAi provides the molecular tool to experimentally disassemble the processes involved in individual cell invasion as well as in different positions of collective invasion. In this procedure, mixtures of fluorescently-labeled cells are plated on the bottom of a Transwell insert previously filled with Matrigel ECM protein, then allowed to invade "upwards" through the filter and into the Matrigel. Reconstruction of z-series image stacks, obtained by confocal imaging, into three-dimensional representations allows for visualization of collectively invading strands and analysis of the representation of fluorescently-labeled cells in leading versus following positions.

Models of tumor cell invasion into three-dimensional extracellular matrix better reflect the in vivo situation than two-dimensional motility assays. Using matrix invasion assays combined with confocal imaging of fluorescently-labeled cells, detailed information on invasion modes and the distinct contributions of leading versus following cells can be obtained.

모델링 및 3 차원 이미징 단체 셀 침략

A defining characteristic of cancer malignancy is invasion and metastasis 1. In some cancers (e.g. glioma 2), local invasion into surrounding healthy ...

In vitro Mesothelial Clearance Assay that Models the Early Steps of Ovarian Cancer Metastasis

Ovarian cancer is the fifth leading cause of cancer related deaths in the United States1. Despite a positive initial response to therapies, 70 to 90 percent of women with ovarian cancer develop new metastases, and the recurrence is often fatal2. It is, therefore, necessary to understand how secondary metastases arise in order to develop better treatments for intermediate and late stage ovarian cancer. Ovarian cancer metastasis occurs when malignant cells detach from the primary tumor site and disseminate throughout the peritoneal cavity. The disseminated cells can form multicellular clusters, or spheroids, that will either remain unattached, or implant onto organs within the peritoneal cavity3 (Figure 1, Movie 1). 
All of the organs within the peritoneal cavity are lined with a single, continuous, layer of mesothelial cells4-6 (Figure 2). However, mesothelial cells are absent from underneath peritoneal tumor masses, as revealed by electron micrograph studies of excised human tumor tissue sections3,5-7 (Figure 2). This suggests that mesothelial cells are excluded from underneath the tumor mass by an unknown process. 
Previous in vitro experiments demonstrated that primary ovarian cancer cells attach more efficiently to extracellular matrix than to mesothelial cells8, and more recent studies showed that primary peritoneal mesothelial cells actually provide a barrier to ovarian cancer cell adhesion and invasion (as compared to adhesion and invasion on substrates that were not covered with mesothelial cells)9,10. This would suggest that mesothelial cells act as a barrier against ovarian cancer metastasis. The cellular and molecular mechanisms by which ovarian cancer cells breach this barrier, and exclude the mesothelium have, until recently, remained unknown. 
Here we describe the methodology for an in vitro assay that models the interaction between ovarian cancer cell spheroids and mesothelial cells in vivo (Figure 3, Movie 2). Our protocol was adapted from previously described methods for analyzing ovarian tumor cell interactions with mesothelial monolayers8-16, and was first described in a report showing that ovarian tumor cells utilize an integrin &#x2013;dependent activation of myosin and traction force to promote the exclusion of the mesothelial cells from under a tumor spheroid17. This model takes advantage of time-lapse fluorescence microscopy to monitor the two cell populations in real time, providing spatial and temporal information on the interaction. The ovarian cancer cells express red fluorescent protein (RFP) while the mesothelial cells express green fluorescent protein (GFP). RFP-expressing ovarian cancer cell spheroids attach to the GFP-expressing mesothelial monolayer. The spheroids spread, invade, and force the mesothelial cells aside creating a hole in the monolayer. This hole is visualized as the negative space (black) in the GFP image. The area of the hole can then be measured to quantitatively analyze differences in clearance activity between control and experimental populations of ovarian cancer and/ or mesothelial cells. This assay requires only a small number of ovarian cancer cells (100 cells per spheroid X 20-30 spheroids per condition), so it is feasible to perform this assay using precious primary tumor cell samples. Furthermore, this assay can be easily adapted for high throughput screening.

In vitro Mesothelial Clearance Assay that Models the Early Steps of Ovarian Cancer Metastasis

The mesothelial clearance assay described here takes advantage of fluorescently labeled cells and time-lapse video microscopy to visualize and quantitatively measure the interactions of ovarian cancer multicellular spheroids and mesothelial cell monolayers. This assay models the early steps of ovarian cancer metastasis.

체외 Mesothelial 정리 분석에서는 그것이 난소 암 전이의 초기 단계 모델

Ovarian cancer is the fifth leading cause of cancer related deaths in the United States1. Despite a positive initial response to therapies, 70 to 90 ...

Quantification of Breast Cancer Cell Invasiveness Using a Three-dimensional (3D) Model

It is now well known that the cellular and tissue microenvironment are critical regulators influencing tumor initiation and progression. Moreover, the extracellular matrix (ECM) has been demonstrated to be a critical regulator of cell behavior in culture and homeostasis in vivo. The current approach of culturing cells on two-dimensional (2D), plastic surfaces results in the disturbance and loss of complex interactions between cells and their microenvironment. Through the use of three-dimensional (3D) culture assays, the conditions for cell-microenvironment interaction are established resembling the in vivo microenvironment. This article provides a detailed methodology to grow breast cancer cells in a 3D basement membrane protein matrix, exemplifying the potential of 3D culture in the assessment of cell invasion into the surrounding environment. In addition, we discuss how these 3D assays have the potential to examine the loss of signaling molecules that regulate epithelial morphology by immunostaining procedures. These studies aid to identify important mechanistic details into the processes regulating invasion, required for the spread of breast cancer.

Quantification of Breast Cancer Cell Invasiveness Using a Three-dimensional 3D Model

This article provides detailed methodologies for the use of three-dimensional (3D) assays to quantify breast cancer cell invasion. Specifically, we discuss the procedures required to set up such assays, quantification, and data analysis, as well as methods to examine the loss of membrane integrity that occurs when cells invade.

3 차원 (3D) 모델을 사용하여 유방암 세포 침윤의 정량화

It is now well known that the cellular and tissue microenvironment are critical regulators influencing tumor initiation and progression. Moreover, the ...

A Modified In vitro Invasion Assay to Determine the Potential Role of Hormones, Cytokines and/or Growth Factors in Mediating Cancer Cell Invasion

Blood serum serves as a chemoattractant towards which cancer cells migrate and invade, facilitating their intravasation into microvessels. However, the actual molecules towards which the cells migrate remain elusive. This modified invasion assay has been developed to identify targets which drive cell migration and invasion. This technique compares the invasion index under three conditions to determine whether a specific hormone, growth factor, or cytokine plays a role in mediating the invasive potential of a cancer cell. These conditions include i) normal fetal bovine serum (FBS), ii) charcoal-stripped FBS (CS-FBS), which removes hormones, growth factors, and cytokines and iii) CS-FBS + molecule (denoted &#8220;X&#8221;). A significant change in cell invasion with CS-FBS as compared to FBS, indicates the involvement of hormones, cytokines or growth factors in mediating the change. Individual molecules can then be added back to CS-FBS to assay their ability to reverse or rescue the invasion phenotype. Furthermore, two or more factors can be combined to evaluate the additive or synergistic effects of multiple molecules in driving or inhibiting invasion. Overall, this method enables the investigator to determine whether hormones, cytokines, and/or growth factors play a role in cell invasion by serving as chemoattractants or inhibitors of invasion for a particular type of cancer cell or a specific mutant. By identifying specific chemoattractants and inhibitors, this modified invasion assay may help to elucidate signaling pathways that direct cancer cell invasion.

A Modified In vitro Invasion Assay to Determine the Potential Role of Hormones, Cytokines and/or Growth Factors in Mediating Cancer Cell Invasion

This video article describes a modified in vitro method to examine the role of hormones, cytokines and/or growth factors in driving cancer cell invasion.

수정<em&gt; 시험관</em&gt; 침공 분석은 호르몬, 중재 암 세포 침략의 사이토 카인 및 / 또는 성장 인자의 잠재적 인 역할을 확인하는

Blood serum serves as a chemoattractant towards which cancer cells migrate and invade, facilitating their intravasation into microvessels. However, the ...

Assessment of Ovarian Cancer Spheroid Attachment and Invasion of Mesothelial Cells in Real Time

Ovarian cancers metastasize by shedding into the peritoneal fluid and dispersing to distal sites within the peritoneum. Monolayer cultures do not accurately model the behaviors of cancer cells within a nonadherent environment, as cancer cells inherently aggregate into multicellular structures which contribute to the metastatic process by attaching to and invading the peritoneal lining to form secondary tumors. To model this important stage of ovarian cancer metastasis, multicellular aggregates, or spheroids, can be generated from established ovarian cancer cell lines maintained under nonadherent conditions. To mimic the peritoneal microenvironment encountered by tumor cells in vivo, a spheroid-mesothelial co-culture model was established in which preformed spheroids are plated on top of a human mesothelial cell monolayer, formed over an extracellular matrix barrier. Methods were then developed using a real-time cell analyzer to conduct quantitative real time measurements of the invasive capacity of different ovarian cancer cell lines grown as spheroids. This approach allows for the continuous measurement of invasion over long periods of time, which has several advantages over traditional endpoint assays and more laborious real time microscopy image analyses. In short, this method enables a rapid, determination of factors which regulate the interactions between ovarian cancer spheroid cells invading through mesothelial and matrix barriers over time.

Ovarian cancer cell invasion into the mesothelial lining of the peritoneum is a dynamic process over time. Utilizing a real time analyzer, the invasive capacity of ovarian cancer cells in a spheroid-mesothelial cell co-culture model can be quantified over prolonged time periods, providing insights into factors regulating the metastatic process.

실시간으로 중피 세포의 난소 암 회전 타원체의 부착과 침략의 평가

Ovarian cancers metastasize by shedding into the peritoneal fluid and dispersing to distal sites within the peritoneum. Monolayer cultures do not ...

Focus Formation: A Cell-based Assay to Determine the Oncogenic Potential of a Gene

Malignant transformation of cells is typically associated with increased proliferation, loss of contact inhibition, acquisition of anchorage-independent growth potential, and the ability to form tumors in experimental animals1. In NIH 3T3 cells, the Ras signal transduction pathway is known to trigger many of these events, what is known as Ras transformation. The introduction of an overexpressed gene in NIH 3T3 cells may promote morphological transformation and loss of contact inhibition, which can help determine the oncogenic potential of that gene of interest. An assay that provides a straightforward method to assess one aspect of the transforming potential of an oncogene is the Focus Formation Assay (FFA)2. When NIH 3T3 cells divide normally in culture, they do so until they reach a confluent monolayer. However, in the presence of an overexpressed oncogene, these cells can begin to grow in dense, multilayered foci1 that can be visualized and quantified by crystal violet or Hema 3 staining. In this article we describe the FFA protocol with retroviral transduction of the gene of interest into NIH 3T3 cells, and how to quantify the number of foci through staining. Retroviral transduction offers a more efficient method of gene delivery than transfection, and the use of an ecotropic murine retrovirus provides a biosafety control when working with potential human oncogenes.

The Focus Formation Assay provides a straightforward method to assess the transforming potential of a candidate oncogene.

형성 초점 : 세포 기반 분석은 유전자의 발암 성 가능성을 파악하기 위해

Malignant transformation of cells is typically associated with increased proliferation, loss of contact inhibition, acquisition of anchorage-independent ...

Carotid Artery Infusions for Pharmacokinetic and Pharmacodynamic Analysis of Taxanes in Mice

When proposing the use of a drug, drug combination, or drug delivery into a novel system, one must assess the pharmacokinetics of the drug in the study model. As the use of mouse models are often a vital step in preclinical drug discovery and drug development1-8, it is necessary to design a system to introduce drugs into mice in a uniform, reproducible manner. Ideally, the system should permit the collection of blood samples at regular intervals over a set time course. The ability to measure drug concentrations by mass-spectrometry, has allowed investigators to follow the changes in plasma drug levels over time in individual mice1, 9, 10. In this study, paclitaxel was introduced into transgenic mice as a continuous arterial infusion over three hours, while blood samples were simultaneously taken by retro-orbital bleeds at set time points. Carotid artery infusions are a potential alternative to jugular vein infusions, when factors such as mammary tumors or other obstructions make jugular infusions impractical. Using this technique, paclitaxel concentrations in plasma and tissue achieved similar levels as compared to jugular infusion. In this tutorial, we will demonstrate how to successfully catheterize the carotid artery by preparing an optimized catheter for the individual mouse model, then show how to insert and secure the catheter into the mouse carotid artery, thread the end of the catheter out through the back of the mouse&#8217;s neck, and hook the mouse to a pump to deliver a controlled rate of drug influx. Multiple low volume retro-orbital bleeds allow for analysis of plasma drug concentrations over time.

This method was developed with the goal of delivering a steady drug solution via the carotid artery, to assess the pharmacokinetics of novel drugs in mouse models.

When proposing the use of a drug, drug combination, or drug delivery into a novel system, one must assess the pharmacokinetics of the drug in the study ...