Wilms' tumour (WT), the second most common abdominal tumour in young children, is often initially responsive to treatment. However, approximately 15% of cases relapse. The tumour microenvironment (TME), which includes cancer cells, including rare drug-resistant variants, vascular elements, fibroblasts and immune cells, can lead to therapeutic failure. A comprehensive understanding of the TME and its constituent cells is essential for the development of novel therapeutic strategies. The aim of our laboratory is to contribute to the elucidation of the tumour microenvironment of Wilms' tumour by applying various techniques, including image-based spatial transcriptomics, transcriptomics and AI-based methods. The aim is to identify prognostic markers and novel therapeutic targets and to facilitate the adaptation of risk-adjusted therapies. In parallel, we are establishing cell culture and animal models to test our hypotheses.