Objective: To investigate whether such tissue fragments could be cultured as organotypic multicellular spheroids since access to biopsy tissue is often limited.
Methods: Tissue fragments obtained by ultrasonic aspiration from 10 glioblastomas and tumor biopsy tissue from seven of these tumors were cultured in serum-containing and serum-free medium. Upon culturing, the fragments formed spheroids, which were prepared for histology. Two glioblastoma cell lines from ultrasonic fragments and biopsy tissue were established as well.
Results: Hematoxylin eosin staining showed viable glioma spheroids obtained from both ultrasonic and biopsy tissue in both types of medium. EGFR and PTEN/chromosome 10 status were found to be preserved in most spheroids (7-8 out of 10 tumors) together with the level of GFAP, VWF and Ki-67. The level of stem cell markers CD133, Bmi-1, nestin and Sox2 was preserved as well. The ultrasonic spheroids had higher levels of GFAP and VWF and a lower level of Bmi-1, nestin, Sox2 and Olig2 compared to that found in conventional biopsy spheroids. For both types of spheroids, the stem cell medium seemed to favor expression of stem cell markers. The established cell lines were both capable of spheroid formation at clonal density and tumor formation in vivo.
Conclusion: Viable organotypic and proliferating spheroids were easily obtained from ultrasonic tissue fragments. The preservation of markers and establishment of cell lines with tumor initiating cell properties suggest ultrasonic spheroids as a new tissue resource for glioma research.
From: Glioma Spheroids Obtained Via Ultrasonic Aspiration are Viable and Express Stem Cell Markers: A New Tissue Resource for Glioma Research by Jensen et al.