NES and cancer: Nestin is an intermediate filament protein originally detected in neuronal stem cells during development.55 Nestin has been detected in various types of solid tumours, including mesenchymal tumours and cancers (e.g., breast, lung, ovarian and gastrointestinal).56 Nestin has been suggested as a stem-cell marker indicating an undifferentiated and thus more invasive phenotype of transformed cells.57 Immunohistochemical staining showed that nestin protein expression was confined to the TME of OAC (Fig. 5b).