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Title: Fibroblast spheroids as a model to study sustained fibroblast quiescence and their crosstalk with tumor cells

Abstract

Stromal fibroblasts have an important role in regulating tumor progression. Normal and quiescent fibroblasts have been shown to restrict and control cancer cell growth, while cancer-associated, i. e. activated fibroblasts have been shown to enhance proliferation and metastasis of cancer cells. In this study we describe generation of quiescent fibroblasts in multicellular spheroids and their effects on squamous cell carcinoma (SCC) growth in soft-agarose and xenograft models. Quiescent phenotype of fibroblasts was determined by global down-regulation of expression of genes related to cell cycle and increased expression of p27. Interestingly, microarray analysis showed that fibroblast quiescence was associated with similar secretory phenotype as seen in senescence and they expressed senescence-associated-β-galactosidase. Quiescent fibroblasts spheroids also restricted the growth of RT3 SCC cells both in soft-agarose and xenograft models unlike proliferating fibroblasts. Restricted tumor growth was associated with marginally increased tumor cell senescence and cellular differentiation, showed with senescence-associated-β-galactosidase and cytokeratin 7 staining. Our results show that the fibroblasts spheroids can be used as a model to study cellular quiescence and their effects on cancer cell progression. - Highlights: • Fibroblasts acquire a sustained quiescence when grown as multicellular spheroids. • This quiescence is associated with drastic change in gene expression. •more » Fibroblasts spheroids secrete various inflammation-linked cytokines and chemokines. • Fibroblasts spheroids reduced growth of RT3 SCC cells in xenograft model.« less

Authors:
 [1];  [2];  [1];  [2];  [1]
  1. Department of Virology, Medicum, Faculty of Medicine, University of Helsinki, P.O. Box 21, FIN-00014 (Finland)
  2. Research Programs Unit, Translational Cancer Biology, and Institute of Biomedicine, University of Helsinki, P.O. Box 63, FIN-00014 (Finland)
Publication Date:
OSTI Identifier:
22648585
Resource Type:
Journal Article
Resource Relation:
Journal Name: Experimental Cell Research; Journal Volume: 345; Journal Issue: 1; Other Information: Copyright (c) 2016 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; CARCINOMAS; CELL CYCLE; FIBROBLASTS; GALACTOSIDASE; GENES; INFLAMMATION; LYMPHOKINES; METASTASES; PHENOTYPE; PHOSPHORUS 27; PLANT GROWTH; PROLIFERATION; SPHEROIDS; STAINS; TUMOR CELLS

Citation Formats

Salmenperä, Pertteli, E-mail: pertteli.salmenpera@helsinki.fi, Karhemo, Piia-Riitta, Räsänen, Kati, Laakkonen, Pirjo, and Vaheri, Antti. Fibroblast spheroids as a model to study sustained fibroblast quiescence and their crosstalk with tumor cells. United States: N. p., 2016. Web. doi:10.1016/J.YEXCR.2016.05.005.
Salmenperä, Pertteli, E-mail: pertteli.salmenpera@helsinki.fi, Karhemo, Piia-Riitta, Räsänen, Kati, Laakkonen, Pirjo, & Vaheri, Antti. Fibroblast spheroids as a model to study sustained fibroblast quiescence and their crosstalk with tumor cells. United States. doi:10.1016/J.YEXCR.2016.05.005.
Salmenperä, Pertteli, E-mail: pertteli.salmenpera@helsinki.fi, Karhemo, Piia-Riitta, Räsänen, Kati, Laakkonen, Pirjo, and Vaheri, Antti. 2016. "Fibroblast spheroids as a model to study sustained fibroblast quiescence and their crosstalk with tumor cells". United States. doi:10.1016/J.YEXCR.2016.05.005.
@article{osti_22648585,
title = {Fibroblast spheroids as a model to study sustained fibroblast quiescence and their crosstalk with tumor cells},
author = {Salmenperä, Pertteli, E-mail: pertteli.salmenpera@helsinki.fi and Karhemo, Piia-Riitta and Räsänen, Kati and Laakkonen, Pirjo and Vaheri, Antti},
abstractNote = {Stromal fibroblasts have an important role in regulating tumor progression. Normal and quiescent fibroblasts have been shown to restrict and control cancer cell growth, while cancer-associated, i. e. activated fibroblasts have been shown to enhance proliferation and metastasis of cancer cells. In this study we describe generation of quiescent fibroblasts in multicellular spheroids and their effects on squamous cell carcinoma (SCC) growth in soft-agarose and xenograft models. Quiescent phenotype of fibroblasts was determined by global down-regulation of expression of genes related to cell cycle and increased expression of p27. Interestingly, microarray analysis showed that fibroblast quiescence was associated with similar secretory phenotype as seen in senescence and they expressed senescence-associated-β-galactosidase. Quiescent fibroblasts spheroids also restricted the growth of RT3 SCC cells both in soft-agarose and xenograft models unlike proliferating fibroblasts. Restricted tumor growth was associated with marginally increased tumor cell senescence and cellular differentiation, showed with senescence-associated-β-galactosidase and cytokeratin 7 staining. Our results show that the fibroblasts spheroids can be used as a model to study cellular quiescence and their effects on cancer cell progression. - Highlights: • Fibroblasts acquire a sustained quiescence when grown as multicellular spheroids. • This quiescence is associated with drastic change in gene expression. • Fibroblasts spheroids secrete various inflammation-linked cytokines and chemokines. • Fibroblasts spheroids reduced growth of RT3 SCC cells in xenograft model.},
doi = {10.1016/J.YEXCR.2016.05.005},
journal = {Experimental Cell Research},
number = 1,
volume = 345,
place = {United States},
year = 2016,
month = 7
}
  • The anti-tumor mechanisms of local LAK cell therapy are difficult to study in vivo. We describe a method to study in vitro the action of LAK cells against three-dimensional tumor tissue. Spherical cell aggregates (spheroids) grown from human glioma cell lines H-2 and U-251 were labeled with 51Cr and then incubated for up to 24 h with LAK cells. After the incubation, most spheroids were still macroscopically identifiable, and the measured reduction of volume did not correlate to the extent of damage. LAK cells infiltrated into spheroid tissue slowly as a frontier which explains why the specific 51Cr release wasmore » clearly slower from spheroids than corresponding single cell suspensions. The infiltrated area was at 1 to 2 h very thin but by 8 to 12 h consisted already of several cell layers. Most H-2 spheroids became totally infiltrated by 16 to 24 h whereas in U-251 spheroids the infiltration usually remained peripheral. In accordance with the different extent of infiltration, H-2 spheroids were clearly more sensitive to LAK cells than U-251 spheroids: at E/T ratio 10:1 the mean specific 51Cr release by 24 h was 63 and 36%, respectively. A single exposure to LAK cells released 51Cr from H-2 spheroids approximately 12 h but over 24 h from U-251 spheroids. The spheroid model can be used to study the infiltrative capacity and cytotoxicity of LAK cells against three-dimensional tumor tissue, and the method may help to find an optimal mode of local LAK cell therapy, i.e., proper combination of lymphokines and LAK cells, and proper timing of their administration.« less
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