Fig. 4

The proposed mechanism for activating the microenvironmental tumor component, fibroblast activation, to enrich stemness in cancer cells: A normal healthy pancreas (denoted blue color) cells surrounded by a normal fibroblast (denoted green color) provided the mechanical and physiological functional support to the pancreas; however, transition into pancreatic tumor cells (denoted sky blue) released cues (TGF-β, IL-6 etc.) and other external factors (ROS) surrounding the tumors made quiescent fibroblasts converted into activated fibroblasts (denoted red color). This vital activation mechanism is considered a crucial event in the enrichment of stemness in tumors (For interpretation of color references in this figure, the reader may suggest referring to the web version of this article). Abbreviations: TGF-β-Transforming growth factor-β; SHH- Sonic hedgehog; BMP4- Bone morphogenetic protein 4; IL6-Interleukin 6; TNF-α-Tumor necrosis factor-α; ROS-reactive oxygen species