종양 기질 상호 작용에 대한 세 가지 차원의 공동 문화 모델

Summary

Here we present a protocol to co-culture in three-dimensions, which is useful for investigating multicellular interactions and extracellular matrix-dependent modulation of cancer cell behavior. In this experimental model, cancer cells are cultured on collagen gels embedded with human cancer-associated fibroblasts.

Abstract

Cancer progression (initiation, growth, invasion and metastasis) occurs through interactions between malignant cells and the surrounding tumor stromal cells. The tumor microenvironment is comprised of a variety of cell types, such as fibroblasts, immune cells, vascular endothelial cells, pericytes and bone-marrow-derived cells, embedded in the extracellular matrix (ECM). Cancer-associated fibroblasts (CAFs) have a pro-tumorigenic role through the secretion of soluble factors, angiogenesis and ECM remodeling. The experimental models for cancer cell survival, proliferation, migration, and invasion have mostly relied on two-dimensional monocellular and monolayer tissue cultures or Boyden chamber assays. However, these experiments do not precisely reflect the physiological or pathological conditions in a diseased organ. To gain a better understanding of tumor stromal or tumor matrix interactions, multicellular and three-dimensional cultures provide more powerful tools for investigating intercellular communication and ECM-dependent modulation of cancer cell behavior. As a platform for this type of study, we present an experimental model in which cancer cells are cultured on collagen gels embedded with primary cultures of CAFs.

Introduction

Cancer tissue can be perceived as a type of organ, which evolves through close interactions between the cancer and the tumor stromal microenvironment, composed of cancer-associated fibroblasts (CAFs), immune cells, tumor vessels and the extracellular matrix (ECM). CAFs are the major source of soluble factors (cytokines, growth factors and chemokines) that exert mitogenic, pro-migratory and pro-invasive effects on cancer cells. They also stimulate tumor vessel formation and recruit precursor cells, such as bone marrow-derived cells (BMDC). Activated CAFs are involved in the production and remodeling of the ECM, thereby promoting the growth and spread of cancer cells¹. CAFs also provide a niche that facilitates tumor cell colonization and metastasis and are capable of conferring stem cell phenotypes onto neighboring cancer cells. Pathological observations suggest that stromal reactions or fibrotic changes in cancer tissues are indicative of a poor prognosis. Recent studies have also demonstrated that tumor stromal features, such as the gene signature, can predict patient prognosis. Furthermore, CAF-derived factors can modulate sensitivity to chemotherapy, highlighting the role of CAFs in determining drug sensitivity and resistance².

As CAFs play a multifaceted role in the promotion of tumor progression through signaling pathways that mediate interactions between CAFs and different cell types within the tumor microenvironment, they have attracted increasing attention as novel targets for cancer therapies. The heterogeneity of the cell populations within the cancer microenvironment presents an obstacle for targeting CAFs. Several markers for CAFs have been proposed, such as α-smooth muscle actin (α-SMA), fibroblast activation protein (FAP), and fibroblast specific proten-1 (FSP-1: also called S100A4); however, these molecular markers are not specific for distinguishing CAFs from other cells present in non-cancerous tissues³. Therefore, further studies are needed to obtain more knowledge about the specific properties of CAFs. To this end, it is informative to characterize primary cultured CAFs compared with patient-matched normal fibroblasts.

Recently, analyses on patient-derived CAFs have been reported in several cancer types, revealing unique gene expression patterns and cell behaviors compared with fibroblasts derived from non-cancerous tissues. Using isolated CAFs from human lung cancer tissues, we developed a three-dimensional co-culture method, enabling us to evaluate the properties of lung CAFs. In this model, we investigated the effects of the CAFs on lung cancer cell invasion, proliferation and collagen gel contraction, which experimentally recapitulated the tumor-promoting roles of lung CAFs⁴.

Protocol

참고 :이 연구는 적절한 윤리위원회에 의해 승인되었다. 인간의 폐 섬유 아 세포의 1 차 문화 폐 조직의 컬렉션 : 직접 수술 수술실에서 인간의 폐 조직 샘플을 얻습니다. 최대한 멀리 종양에서 수집 비 암성 샘플, 암성 및 비 암성 폐 조직으로부터 약 1cm 3 블록 모아서. 둘 베코 변형 이글 배지 100 단위 / ㎖ 페니실린, 100 ㎍ / ml의 스트렙토 마이신 …

Representative Results

이 공동 배양법, 종양 미세 환경을 흉내 낸 콜라겐 젤에 포함 된 암 세포와 섬유 아세포와의 상호 작용을 연구하기위한 유용한 도구이다. 콜라겐 겔 수축, 암세포의 침윤 및 형태 변화 : 이전의 연구에서, 세 개의 파라미터가이 실험 모델에서 평가 하였다. 암 세포의 증식은 또한 면역 염색 Ki67 4를 이용하여 추정 하였다. 폐 조직 샘플을 절제 폐 로브 (도 1A)의 암 및 암이 아닌 ?…

Discussion

CAFS 암세포 주변 ECM의 주요 구성 요소를 형성하고, 종양 만 골격을 제공 할뿐만 아니라 적극적으로 종양 발생에 관여하지 ^7. 축적 된 증거 CAF 매개 종양 진행 ^(8)의 중요한 역할을 강조 최종 예후에 CAFS 또는 관련 분자의 영향을 풀어 낸다.

이전 연구에서는 폐 CAFS ^(4)를 분리하는 가지 방법을 사용. 이 실험에서는, 접시 표면에 조직 절편 밀착성의 유지가…

Materials

Name	Company	Catalog Number
DMEM	Sigma-Aldrich	D5796
FBS	GIBCO	10437
Collagen type IA	Nitta gelatin Inc.	CELL-1A
Reconstitution buffer	Nitta gelatin Inc.
Cover slip	NUNC	174934
Silicone grease	Dow Corning Toray	High vacuum grease
Dispase I	WAKO	386-02271
6-well plate	BD Falcon	353046
Cell strainer (70 μm)	BD Falcon	352350