title: Spheroid-plug model as a tool to study tumor development, angiogenesis, and heterogeneity in vivo.
abstract: Subcutaneous injection of the tumor cell suspension is a simple and commonly used tool for studying tumor development in vivo. However, subcutaneous models poorly resemble tumor complexity due to the fast growth not reflecting the natural course. Here, we describe an application of the new spheroid-plug model to combine the simplicity of subcutaneous injection with improved resemblance to natural tumor progression. Spheroid-plug model relies on in vitro formation of tumor spheroids, followed by injection of single tumor spheroid subcutaneously in Matrigel matrix. In spheroid-plug model, tumors grow slower in comparison to tumors formed by injection of cell suspension as assessed by 3D ultrasonography (USG) and in vivo bioluminescence measurements. The slower tumor growth rate in spheroid-plug model is accompanied by reduced necrosis. The spheroid-plug model ensures increased and more stable vascularization of tumor than classical subcutaneous tumor model as demonstrated by 3D USG Power Doppler examination. Flow cytometry analysis showed that tumors formed from spheroids have enhanced infiltration of endothelial cells as well as hematopoietic and progenitor cells with stem cell phenotype (c-Kit(+) and Sca-1(+)). They also contain more tumor cells expressing cancer stem cell marker CXCR4. Here, we show that spheroid-plug model allows investigating efficiency of anticancer drugs. Treatment of spheroid-plug tumors with known antiangiogenic agent axitinib decreased their size and viability. The antiangiogenic activity of axitinib was higher in spheroid-plug model than in classical model. Our results indicate that spheroid-plug model imitates natural tumor growth and can become a valuable tool for cancer research.
authors.affiliation: Department of Medical Biotechnology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland.|Centre for Molecular Biophysics, Cell Recognition and Glycobiology, UPR4301-CNRS, Orleans, France.
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Szade
authors.affiliation: Department of Medical Biotechnology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland.
authors.forename: Monika
authors.initials: M
authors.lastname: Zukowska
authors.affiliation: Department of Medical Biotechnology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland.
authors.forename: Agata
authors.initials: A
authors.lastname: Szade
authors.affiliation: Centre for Molecular Biophysics, Cell Recognition and Glycobiology, UPR4301-CNRS, Orleans, France.|Skaggs School of Pharmacy and Pharmaceutical Sciences, Laboratory of Bioresponsive Materials, University of California, San Diego, CA, USA.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Collet
authors.affiliation: Department of Medical Biotechnology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland.
authors.forename: Damian
authors.initials: D
authors.lastname: Kloska
authors.affiliation: Centre for Molecular Biophysics, Cell Recognition and Glycobiology, UPR4301-CNRS, Orleans, France.|Malopolska Centre of Biotechnology, Krakow, Poland.
authors.forename: Claudine
authors.initials: C
authors.lastname: Kieda
authors.affiliation: Department of Medical Biotechnology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland. alicja.jozkowicz@uj.edu.pl.
authors.forename: Alicja
authors.initials: A
authors.lastname: Jozkowicz
authors.affiliation: Department of Medical Biotechnology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland. jozef.dulak@uj.edu.pl.|Malopolska Centre of Biotechnology, Krakow, Poland. jozef.dulak@uj.edu.pl.
authors.forename: Jozef
authors.initials: J
authors.lastname: Dulak
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology; D000077784:Axitinib; D014408:Biomarkers, Tumor / Q000378:metabolism; D063646:Carcinogenesis / Q000378:metabolism / Q000473:pathology*; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D003094:Collagen / Q000378:metabolism; D004338:Drug Combinations; D042783:Endothelial Cells / Q000378:metabolism / Q000473:pathology; D006412:Hematopoietic Stem Cells / Q000378:metabolism / Q000473:pathology; D007093:Imidazoles / Q000494:pharmacology; D007191:Indazoles / Q000494:pharmacology; D007279:Injections, Subcutaneous / Q000379:methods; D007797:Laminin / Q000378:metabolism; D008546:Melanoma, Experimental / Q000378:metabolism / Q000473:pathology; D051379:Mice; D008810:Mice, Inbred C57BL; D014411:Neoplastic Stem Cells / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D009389:Neovascularization, Pathologic / Q000378:metabolism / Q000473:pathology*; D011509:Proteoglycans / Q000378:metabolism; D019718:Receptors, CXCR4 / Q000378:metabolism; D018874:Spheroids, Cellular / Q000378:metabolism / Q000473:pathology*; D014407:Tumor Cells, Cultured
chemical_list: D000970:Antineoplastic Agents; D014408:Biomarkers, Tumor; C527276:CXCR4 protein, human; D004338:Drug Combinations; D007093:Imidazoles; D007191:Indazoles; D007797:Laminin; D011509:Proteoglycans; D019718:Receptors, CXCR4; C059485:matrigel; D003094:Collagen; D000077784:Axitinib
keywords: B16 melanoma; Cancer stem cells; Lewis lung carcinoma (LLC); Necrosis; Tumor complexity; Tumor infiltration; Tumor vascularization