Migration and vascular lumen formation of endothelial cells in cancer cell spheroids of various sizes

Abstract

We developed a microfluidic device to culture cellular spheroids of controlled sizes and suitable for live cell imaging by selective plane illumination microscopy (SPIM). We cocultured human umbilical vein endothelial cells (HUVECs) within the spheroids formed by hepatocellular carcinoma cells, and studied the distributions of the HUVECs over time. We observed that the migration of HUVECs depended on the size of spheroids. In the spheroids of $200 lm diameters, HUVECs migrated outwards to the edges within 48 h; while in the spheroids of $250 lm diameters, there was no outward migration of the HUVECs up to 72 h. In addition, we studied the effects of pro-angiogenic factors, namely, vascular endothelial growth factor (VEGF) and fibroblast growth factor (b-FGF), on the migration of HUVECs in the carcinoma cell spheroid. The outward migration of HUVECs in 200 lm spheroids was hindered by the treatment with VEGF and b-FGF. Moreover, some of the HUVECs formed hollow lumen within 72 h under VEGF and b-FGF treatment. The combination of SPIM and microfluidic devices gives high resolution in both spatial and temporal domains. The observation of HUVECs in spheroids provides us insight on tumor vascularization, an ideal disease model for drug screening and fundamental studies.

Three‐dimensional imaging flow cytometry through light‐sheet fluorescence microscopy

“…Reproduced from Ref. ( ) with permission from AIP Publishing LLC. C : Agarose container containing the 3D cell‐collagen mix for the TC‐LSFM set up.…”

Light-sheet microscopy: a tutorial

“…These combined effects offer a technique that allows the user to minimize both photobleaching and phototoxicity [10,[12][13][14], while allowing for long-term imaging studies (up to several days). This is an essential characteristic required for all sorts of developmental biology studies [15][16][17][18], such as organogenesis [19], cell migration [20,21], cardiac development [22][23][24][25], vascular development [26,27], neuro-development [28,29], and generally any kind of in vivo studies. Drosophila melanogaster [2,[30][31][32] and zebrafish [19,26,30,[33][34][35][36] have traditionally been the most widely used samples in this field, but it fits well many others, such as worm embryos [28,37] and other small organisms or plants [38][39][40].…”

“…9(a) and by using Eq. (27), it is possible to calculate the 3D LS intensity distribution and the overall PSF/MTF of the LSFM.…”

“…However, this structure is highly attenuated in the effective PSF of the microscope, as a result of the multiplication operation in the definition of the overall PSF [Eq. (27)]. …”

Preface to Special Topic: Selected Papers from the Advances in Microfluidics and Nanofluidics 2014 Conference in Honor of Professor Hsueh-Chia Chang's 60th Birthday

“…Patra et al reported migration and vascular lumen formation of cancer cell spheroids. 11 This group combined microfluidic devices and selective plane illumination microscopy (SPIM), which gives high resolution in both spatial and temporal domain. The observation of endothelial cells in spheroids provides insight on tumor vascularization, an ideal disease model for drug screening and fundamental studies.…”