STAT3 and cancer: Furthermore, mesothelial cells contribute to the creation of a tumor‐promoting niche by transitioning to cancer‐associated fibroblasts via mesothelial‐to‐mesenchymal transition (Sandoval et al, 2013) and secreting factors including PAI‐1, which activates the oncogenic transcription factor STAT3 on cancer cells (Hendrikson et al, 2022).