Abstract

Arteannuin B (Art B), a sesquiterpene lactone from Artemisia annua , combats non‐small cell lung cancer (NSCLC) chemoresistance by activating a novel miR‐194‐3p/CLDN2 axis, as identified here through integrated transcriptomic and functional analyses. Here, we combined transcriptomic profiling with functional validation to identify claudin‐2 (CLDN2) as a critical mediator of Art B's anticancer effects in NSCLC. CLDN2 , significantly upregulated in NSCLC tissues versus paired normal tissues, promoted tumor cell proliferation and cisplatin resistance by upregulating multidrug resistance‐associated protein 2 (MRP2). Mechanistically, miR‐194‐3p directly binds to two conserved sites (nt 358–365 and 1232–1238) within the CLDN2 3′ UTR, suppressing its expression via mRNA degradation and translational inhibition, thereby attenuating proliferation and resensitizing cells to cisplatin. Importantly, Art B exerted antitumor effects by upregulating miR‐194‐3p , which subsequently inhibited CLDN2 . This study not only elucidates a previously unrecognized mechanism for overcoming chemoresistance but also nominates CLDN2 as a prognostic biomarker, offering a promising therapeutic strategy that could benefit NSCLC patients facing treatment failure. Arteannuin B (Art B), a sesquiterpene lactone from  Artemisia annua , upregulates  miR‐194‐3p , which directly targets two conserved sites (nt 358–365 and 1232–1238) in the CLDN2 3′ UTR. This triggers mRNA decay and blocks translation, suppressing CLDN2 expression. Downregulation of CLDN2 inhibits MRP2‐mediated cisplatin (DDP) resistance in non‐small cell lung cancer (NSCLC). The right panel illustrates the oncogenic role of CLDN2 in promoting MRP2 expression and chemoresistance.