Targeting lysyl oxidase (LOX) overcomes chemotherapy resistance in triple negative breast cancer

Creative Commons License

Saatci O., Kaymak A., Raza U., Ersan P., Akbulut O., Banister C., ...More

NATURE COMMUNICATIONS, vol.11, no.1, 2020 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 11 Issue: 1
  • Publication Date: 2020
  • Doi Number: 10.1038/s41467-020-16199-4
  • Journal Name: NATURE COMMUNICATIONS
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Agricultural & Environmental Science Database, BIOSIS, CAB Abstracts, Chemical Abstracts Core, EMBASE, Geobase, INSPEC, MEDLINE, Veterinary Science Database, Directory of Open Access Journals
  • Hacettepe University Affiliated: Yes

Abstract

Chemoresistance is a major obstacle in triple negative breast cancer (TNBC), the most aggressive breast cancer subtype. Here we identify hypoxia-induced ECM re-modeler, lysyl oxidase (LOX) as a key inducer of chemoresistance by developing chemoresistant TNBC tumors in vivo and characterizing their transcriptomes by RNA-sequencing. Inhibiting LOX reduces collagen cross-linking and fibronectin assembly, increases drug penetration, and downregulates ITGA5/FN1 expression, resulting in inhibition of FAK/Src signaling, induction of apoptosis and re-sensitization to chemotherapy. Similarly, inhibiting FAK/Src results in chemosensitization. These effects are observed in 3D-cultured cell lines, tumor organoids, chemoresistant xenografts, syngeneic tumors and PDX models. Re-expressing the hypoxia-repressed miR-142-3p, which targets HIF1A, LOX and ITGA5, causes further suppression of the HIF-1 alpha /LOX/ITGA5/FN1 axis. Notably, higher LOX, ITGA5, or FN1, or lower miR-142-3p levels are associated with shorter survival in chemotherapy-treated TNBC patients. These results provide strong pre-clinical rationale for developing and testing LOX inhibitors to overcome chemoresistance in TNBC patients. The development of chemoresistance is a major hurdle in triple negative breast cancer (TNBC). Here, the authors show that lysyl oxidase (LOX) is overexpressed in chemoresistant TNBCs, and when inhibited reduces collagen cross-linking, fibronectin fibril assembly, and downstream integrin signalling, overcoming resistance.