LIF and neoplasm: In PDAC, silencing circFARP1 in CAFs inhibits the ability of CAFs to induce tumor cell stemness and gemcitabine resistance by regulating the secretion of leukemia inhibitory factor (LIF) and downstream STAT3 signaling pathway, which is modulated by the circFARP1/miR‐660‐3p/LIF axis and direct interaction between circFARP1 and CAV1.350