Lung mesenchymal cells function as an inductive microenvironment for human lung cancer propagating cells

• Published in: European journal of cardio-thoracic surgery 2014-12, Vol.46 (6), p.e103-e112
• Main Authors: Ampollini, Luca, Madeddu, Denise, Falco, Angela, Frati, Caterina, Lorusso, Bruno, Graiani, Gallia, Saccani, Francesca, Gervasi, Andrea, Rossetti, Pietro, Bonomini, Sabrina, Gnetti, Letizia, Lagrasta, Costanza Annamaria, Silini, Enrico Maria, Quaini, Eugenio, Petronini, Piergiorgio, Alfieri, Roberta, Rusca, Michele, Carbognani, Paolo, Quaini, Federico
• Format: Article
• Language: English
• Subjects: Adult; Aged; Aged, 80 and over; Animals; Carcinogenesis - pathology; Carcinoma, Non-Small-Cell Lung - pathology; Cell Line, Tumor; Female; Heterografts; Humans; Lung - pathology; Lung Neoplasms - pathology; Male; Mesenchymal Stromal Cells - pathology; Mice; Mice, Inbred BALB C; Mice, Nude; Middle Aged; Neoplasm Transplantation; Neoplastic Stem Cells - pathology; Tumor Microenvironment
• ISSN: 1010-7940; 1873-734X
• DOI: 10.1093/ejcts/ezu359

The aim of the present study was to characterize the biological properties and in vivo tumourigenic potential of mesenchymal cells (MCs) obtained from non-small-cell lung cancer (NSCLC) samples. NSCLC samples (53 adenocarcinomas and 24 squamous-cell carcinomas) surgically removed from 46 males and 31 females were processed to identify mesenchymal cells from human lung cancer (hLc-MCs). hLc-MCs were separated from neoplastic epithelial cells, expanded and extensively characterized in vitro. Subsequently, female BALB/c nude mice were subcutaneously injected with either 10(6) or 2.5 × 10(6) Calu-3 (human adenocarcinoma cell line able to reproducibly induce xenografted tumours) alone or in combination with equal doses of hLc-MCs. Control animals were injected with the two doses of hLc-MCs only. Primary cultures of hLc-MCs were obtained from >80% of NSCLC specimens. The typical MCs immunophenotype was documented by the expression of CD90, CD105, CD73, CD13 and CD44 at fluorescence-activated cell sorting analysis. CD45, CD14, CD34 and epithelial antigens were negative while CD117 (c-kit) and CD133 (prominin) were partially expressed. Interestingly, nuclear transcription factors octamer-binding transcription factor 3/4 and sex determining region Y-box 2 involved in stemness, thyroid transcription factor 1 in bronchoalveolar commitment, and ETS1 in carcinogenesis, were expressed in hLc-MCs isolated from NSCLC. Specific conditioned media and cocultures confirmed the supportive role of hLc-MCs for cancer cells. In vivo experiments showed that at both doses Calu-3 xenografts doubled in size when hLc-MCs were coinjected. Cell tracking in xenografted tumours, by immunofluorescence combined with fluorescence in situ hybridization analysis, documented hX-chromosome-labelled, Calu-3-derived cytokeratin-positive adenocarcinoma structures surrounded by hLc-MCs. Tumour-propagating cells require the inductive interaction of resident mesenchymal cells to foster lung cancer development.