Triple-negative breast cancers (TNBCs) are hard-to-treat breast tumors with poor prognosis, which need to be treated by chemotherapy. Signal transducer and activator of transcription 3 (STAT3) is a transcription factor involved in proliferation, metastasis, and invasion of cancer cells. Therefore, research on searching for promising compounds with metabolism that suppress phosphorylation or transcription of STAT3 in TNBC cells is important. Farfarae Flos is well known as a traditional medicine for treating inflammation. However, few studies have shown that sesquiterpenoids from Farfarae Flos have an anticancer effect. In this study, efficient separation methods and an MTT assay were conducted to isolate an anticancer compound from Farfarae Flos against TNBC MDA-MB-231 cells. Here, 7β-(3-Ethyl-cis-crotonoyloxy)-1α-(2-methylbutyryloxy)-3,14-dehydro-Z-notonipetranone (ECN), a compound isolated from Farfarae Flos showed a potent cytotoxic effect on MDA-MB-231 cells. ECN inhibited JAK–STAT3 signaling and suppressed the expression of STAT3 target genes. In addition, ECN induced apoptosis through both extrinsic and intrinsic pathways. Furthermore, we investigated that ECN inhibited the growth of tumors by intraperitoneal administration in mice injected with MDA-MB-231 cells. Therefore, ECN can be an effective chemotherapeutic agent for breast cancer treatment.

Dysfunctional resolution of intestinal inflammation and altered mucosal healing are essential features in the pathogenesis of inflammatory bowel disease (IBD). Intestinal macrophages are vital in the process of resolution of inflammation but the mechanisms underlying their mucosal healing capacity remains elusive. Here, we describe a subset of E prostanoid receptor 4 (EP4) expressing intestinal macrophages with mucosal healing properties both in human and mice. Notably, Csf1r-iCre EP4-fl/fl mice showed defective mucosal healing and intestinal epithelial barrier regeneration in a dextran sodium sulfate-induced colitis model. Mechanistically, an increased mucosal level of prostaglandin E2 (PGE2) triggers the secretion of chemokine (C-X-C motif) ligand 1 (CXCL1) in monocyte-derived EP4 ⁺ macrophages via MAPKs. Subsequently, CXCL1 drives epithelial cell differentiation and proliferation from regenerating crypts during the resolution phase of colitis. Thus, EP4 ⁺ intestinal macrophages are essential for the support of the intestinal stem cell niche and for the regeneration of the injured epithelium. One Sentence Summary: Prostaglandin E2 licenses E-type prostanoid receptor 4 intestinal macrophage regenerative capacity promoting mucosal healing via the secretion of CXCL1