Breast cancers that disseminate to bone marrow acquire aggressive phenotypes through CX43-related tumor-stroma tunnels
Saptarshi Sinha, Brennan W. Callow, Alex P. Farfel, Suchismita Roy, Siyi Chen, Maria Masotti, Shrila Rajendran, Johanna M. Buschhaus, Celia R. Espinoza, Kathryn E. Luker, Pradipta Ghosh, Gary D. Luker
Saptarshi Sinha, Brennan W. Callow, Alex P. Farfel, Suchismita Roy, Siyi Chen, Maria Masotti, Shrila Rajendran, Johanna M. Buschhaus, Celia R. Espinoza, Kathryn E. Luker, Pradipta Ghosh, Gary D. Luker
View: Text | PDF
Research Article Oncology

Breast cancers that disseminate to bone marrow acquire aggressive phenotypes through CX43-related tumor-stroma tunnels

Abstract

Estrogen receptor-positive (ER+) breast cancer commonly disseminates to bone marrow, where interactions with mesenchymal stromal cells (MSCs) shape disease trajectory. We modeled these interactions with tumor-MSC co-cultures and used an integrated transcriptome-proteome-network-analyses workflow to identify a comprehensive catalog of contact-induced changes. Conditioned media from MSCs failed to recapitulate genes and proteins, some borrowed and others tumor-intrinsic, induced in cancer cells by direct contact. Protein-protein interaction networks revealed the rich connectome between “borrowed” and “intrinsic” components. Bioinformatics prioritized one of the borrowed components, CCDC88A/GIV, a multi-modular metastasis-related protein that has recently been implicated in driving a hallmark of cancer, growth signaling autonomy. MSCs transferred GIV protein to ER+ breast cancer cells (that lack GIV) through tunnelling nanotubes via connexin (Cx)43-facilitated intercellular transport. Reinstating GIV alone in GIV-negative breast cancer cells reproduced approximately 20% of both the borrowed and the intrinsic gene induction patterns from contact co-cultures; conferred resistance to anti-estrogen drugs; and enhanced tumor dissemination. Findings provide a multiomic insight into MSC→tumor cell intercellular transport and validate how transport of one such candidate, GIV, from the haves (MSCs) to have-nots (ER+ breast cancer) orchestrates aggressive disease states.

Authors

Saptarshi Sinha, Brennan W. Callow, Alex P. Farfel, Suchismita Roy, Siyi Chen, Maria Masotti, Shrila Rajendran, Johanna M. Buschhaus, Celia R. Espinoza, Kathryn E. Luker, Pradipta Ghosh, Gary D. Luker

×

Figure 6

Transfer of GIV from MSCs to ER+ breast cancer cells requires ongoing interactions.

Options: View larger image (or click on image) Download as PowerPoint
Transfer of GIV from MSCs to ER+ breast cancer cells requires ongoing in...
(A) Schematic illustrates key functional domains of GIV. The C-terminus contains multiple short linear motifs that enable diverse tumor-promoting interactions (receptors, signaling molecules within diverse pathways, and components of membrane trafficking). GBD, G protein–binding domain; GEM, guanine nucleotide exchange modulator; SH2, Src-like homology domain. (B) Equal aliquots of lysates of 3 ER+ breast cancer cells (MCF7, T47D, or HCC1428) in monoculture or recovered after co-culture with HS5 cells were analyzed for GIV and actin (as a loading control) by immunoblotting (IB). (C) Equal aliquots of lysates of MCF7 cells prepared either immediately after recovery from co-cultures with HS5 cells (0 hours) or after an additional 24 or 96 hours of culture after removal from HS5 contact were analyzed for GIV and actin (as a loading control) by IB. (D and E) Schematic (D) outlines the key manipulations (i.e., treatment with shRNA for GIV) done to either MCF7 or HS5 cells in contact co-cultures. Equal aliquots of MCF7 cells recovered from the co-cultures (left) or HS5 cells in monocultures were analyzed for GIV and actin (loading control) by IB.