Glioblastoma is the most dangerous brain cancer. One reason for glioblastoma's aggressiveness are glioblastoma stem‐like cells. To target them, a number of markers have been proposed (CD133, CD44, CD15, A2B5, CD36, CXCR4, IL6R, L1CAM, and ITGA6). A comprehensive study of co‐expression patterns of them has, however, not been performed so far. Here, we mapped the multidimensional co‐expression profile of these stemness‐associated molecules. Gliomaspheres – an established model of glioblastoma stem‐like cells – were used. Seven different gliomasphere systems were subjected to multicolor flow cytometry measuring the nine markers CD133, CD44, CD15, A2B5, CD36, CXCR4, IL6R, L1CAM, and ITGA6 all simultaneously based on a novel 9‐marker multicolor panel developed for this study. The viSNE dimensionality reduction algorithm was applied for analysis. All gliomaspheres were found to express at least five different glioblastoma stem‐like cell markers. Multi‐dimensional analysis showed that all studied gliomaspheres consistently harbored a cell population positive for the molecular signature CD44+/CD133+/ITGA6+/CD36+. Glioblastoma patients with an enrichment of this combination had a significantly worse survival outcome when analyzing the two largest available The Cancer Genome Atlas datasets (MIT/Harvard Affymetrix: P = 0.0015, University of North Carolina Agilent: P = 0.0322). In sum, we detected a previously unknown marker combination – demonstrating feasibility, usefulness, and importance of high‐dimensional gliomasphere marker combinatorics.

No abstract

A subset of colorectal cancer (CRC) with a mesenchymal phenotype (CMS4) displays an aggressive disease, with an increased risk of recurrence after surgery, reduced survival, and resistance to standard treatments. It has been shown that the AXL and TGFβ signaling pathways are involved in epithelial-to-mesenchymal transition, migration, metastatic spread, and unresponsiveness to targeted therapies. However, the prognostic role of the combination of these biomarkers and the anti-tumor effect of AXL and TGFβ inhibition in CRC still has to be assessed. To evaluate the role of AXL and TGFβ as negative biomarker in CRC, we conducted an in-depth in silico analysis of CRC samples derived from the Gene Expression Omnibus. We found that AXL and TGFβ receptors are upregulated in CMS4 tumors and are correlated with an increased risk of recurrence after surgery in stage II/III CRC and a reduced overall survival. Moreover, we showed that AXL receptor is differently expressed in human CRC cell lines. Dual treatment with the TGFβ galunisertib and the AXL inhibitor, bemcentinib, significantly reduced colony formation and migration capabilities of tumor cells and displayed a strong anti-tumor activity in 3D spheroid cultures derived from patients with advanced CRC. Our work shows that AXL and TGFβ receptors identify a subgroup of CRC with a mesenchymal phenotype and correlate with poor prognosis. Dual inhibition of AXL and TGFβ could represent a novel therapeutic strategy for patients with this aggressive disease.