The Yin and Yang of GDF15: a secreted biomarker of eribulin response in breast cancer cells, yet required for survival of drug tolerant persister (DTP) cells

ABSTRACT: Drug tolerant persister (DTP) cells enter into a reversible slow-cycling state after cancer drug treatment. These cells are the living proof of response to a drug, and an interesting experimental subject for biomarker discovery. Here, we performed proteomic characterization of the breast cancer (BC) DTP cell secretome after eribulin treatment. First, we showed that eribulin induces a specific secretome in DTP cells as compared to other microtubule targeting agents. Then, we selected and functionally validated growth differentiation factor 15 (GDF15) as a protein significantly over-secreted upon eribulin treatment. Interestingly, GDF15 expression is low/absent in cells that are sensitive to eribulin, strongly upregulated during the response to the drug, and downregulated when stable resistance is ultimately established. Proteomic results were confirmed in 3D-cell culture models using BC cells lines and PDXs, as well as in a TNBC in vivo model. Unexpectedly, despite its biomarker potential for eribulin response, we found that GDF15 is also paradoxically required for survival of DTP cells, although once full resistance to eribulin is established, GDF15 expression largely disappears. Direct participation of GDF15 and its receptor GFRAL in eribulin-induction of DTPs was established by the enhanced cell killing of DTPs by eribulin seen under GDF15 and GFRAL loss of function conditions. These results pointed to a potential benefit of simultaneous targeting of GDF15/GFRAL and eribulin, and indeed we showed that combination therapy of eribulin plus an anti-GDF15 antibody kills BC-DTP cells. Our results suggest that targeting GDF15 may help eradicate DTP cells and block the onset of acquired eribulin resistance, and possibly other cytotoxic drugs. Overall, the combination of cytotoxic agents with targeted agents aimed specifically at DTP cells could be an effective therapeutic approach for metastatic breast cancer patients.

INSTRUMENT(S): LTQ Orbitrap Velos

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Epithelial Cell, Cell Culture

DISEASE(S): Breast Cancer

SUBMITTER: Francesc Canals  

LAB HEAD: Josep Villanueva

PROVIDER: PXD034037 | Pride | 2023-01-09

REPOSITORIES: Pride