New ex-ovo colorectal-cancer models from different SdFFF-sorted tumor-initiating cells

Abstract

Despite effective treatments, relapse of colorectal cancer (CRC) is frequent, in part caused by the existence of tumor-initiating cells (TICs). Different subtypes of TICs, quiescent and activated, coexist in tumors, defining the tumor aggressiveness and therapeutic response. These subtypes have been sorted by hyperlayer sedimentation field-flow fractionation (SdFFF) from WiDr and HCT116 cell lines. On the basis of a new strategy, including TIC SdFFF sorting, 3D Matrigel amplification, and grafting of corresponding TIC colonies on the chick chorioallantoic membrane (CAM), specific tumor matrices could be obtained. If tumors had similar architectural structure with vascularization by the host system, they had different proliferative indices in agreement with their initial quiescent or activated state. Protein analysis also revealed that tumors obtained from a population enriched for "activated" TICs lost "stemness" properties and became invasive. In contrast, tumors obtained from a population enriched for "quiescent" TICs kept their stemness properties and seemed to be less proliferative and invasive. Then, it was possible to produce different kinds of tumor which could be used as selective supports to study carcinogenesis and therapy sensitivity.

A Label-Free Cell Sorting Approach to Highlight the Impact of Intratumoral Cellular Heterogeneity and Cancer Stem Cells on Response to Therapies

“…Using a hyperlayer elution mode, cells were eluted according to their biophysical properties mainly their size and density, but also their shape and rigidity. This last parameter is deeply related to the cell differentiation status [ 10 , 12 , 19 ]. According to this elution mode, the beginning of the elution peak was more composed of large and low-density cells, while the end of the peak contains small and high-density cells [ 10 ].…”

“…In previous work, our laboratory used SdFFF as a tool to isolate cell subpopulations independently of surface marker expression from CRC cell lines [ 10 ]. Results showed that one of the cell subpopulations sorted by SdFFF exhibited CSC-like features in two early-stage CRC cell lines [ 10 , 12 ]. However, the ability of this cell subpopulation to initiate tumors in mice, which is the gold standard for defining a CSC, remains to be determined.…”

Dual inhibition of BDNF/TrkB and autophagy: a promising therapeutic approach for colorectal cancer

“…Four micrometre paraffin sections were realized and stained with haematoxylin‐eosin‐safran (HES), to evaluate necrotic areas. For proliferation rate assessement, Ki67 staining was performed as previously described using BenchMark Technology (Ventana Medical Systems; Anatomopathology department from the Limoges’ Hospital). Images were acquired with the Nanozoomer Digital Pathology 2.ORS software.…”

Benefits of functional assays in personalized cancer medicine: more than just a proof-of-concept

“…A surrogate approach investigated the neutralizing effect of bevacizumab on circulating VEGF using a VEGF-dependent cell line subjected to sera of cancer patients treated with bevacizumab suggested potential to predict clinical benefit 164 . Chick chorioallantoic membrane (CAM) assay has also established as an interesting model to study tumorigenesis and antiangiogenic treatment effects 165 , 166 . This approach, easier to implement than PDX, may thus be considered as well for tumour response prediction studies.…”