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Hayward, M.-K.

Publications and source records attributed to Hayward, M.-K..

4 recordsLinked to original sources

Single molecule Grb2 dynamics reveal spatiomechanical modulation of RTK signaling across length scales

Extracellular matrix (ECM)-mediated cell adhesion and tension regulate development and disease through crosstalk with Receptor Tyrosine Kinases (RTKs). RTKs stimulate proliferation, survival, and metabolic reprogramming via Ras/ERK and PI3K/Akt signaling. Emerging evidence identify the biophysical and biochemical integration of integrin-mediated adhesions with RTK signaling, however, the molecular mechanisms regulating this phenotype remain poorly understood. Here, we demonstrate that ECM stiffness potentiates ligand-mediated epidermal growth factor receptor (EGFR) signaling at scales ranging from the single adaptor protein, Grb2 upward to multicellular spheroids and tissues. We show that ECM stiffness-driven RTK signaling is mediated by integrin adhesions that reshape the membrane to induce the formation of RTK signaling hotspots distributed globally across the cell membrane. A parsimonious computational model and biochemical membrane perturbations causally implicate membrane curvature and topography in tension-dependent integrin-EGFR crosstalk. The results demonstrate how the mechanical properties of the ECM direct molecular recruitment and confinement of signaling molecules to regulate growth factor-dependent RTK signaling. Given that many RTK-driven solid tumors develop a stiff stroma, the findings could explain why many therapeutic tyrosine kinase inhibitors develop clinical resistance. The findings suggest clarifying how tension regulates transmembrane receptor signaling could identify unique force-dependent molecular regulators towards which new antitumor therapies could be applied.

biophysics↗

Tumor Cell Spatial Organization Directs EGFR/RAS/RAF Pathway Primary Therapy Resistance through YAP Signaling

Non-small cell lung cancers (NSCLC) harboring common mutations in EGFR and KRAS characteristically respond transiently to targeted therapies against those mutations, but invariably, tumors recur and progress. Resistance often emerges through mutations in the therapeutic target or activation of alternative signaling pathways. Mechanisms of acute tumor cell resistance to initial EGFR (EGFRi) or KRASG12C (G12Ci) pathway inhibition remain poorly understood. Our study reveals that acute response to EGFR/RAS/RAF-pathway inhibition is spatial and culture context specific. In vivo, EGFR mutant tumor xenografts shrink by > 90% following acute EGFRi therapy, and residual tumor cells are associated with dense stroma and have increased nuclear YAP. Interestingly, in vitro EGFRi induced cell cycle arrest in NSCLC cells grown in monolayer, while 3D spheroids preferentially die upon inhibitor treatment. We find differential YAP nuclear localization and activity, driven by the distinct culture conditions, as a common resistance mechanism for selective EGFR/KRAS/BRAF pathway therapies. Forced expression of the YAPS127A mutant partially protects cells from EGFR-mediated cell death in spheroid culture. These studies identify YAP activation in monolayer culture as a non-genetic mechanism of acute EGFR/KRAS/BRAF therapy resistance, highlighting that monolayer vs spheroid cell culture systems can model distinct stages of patient cancer progression. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=99 SRC="FIGDIR/small/615226v3_ufig1.gif" ALT="Figure 1"> View larger version (38K): org.highwire.dtl.DTLVardef@1b22ef5org.highwire.dtl.DTLVardef@128ed3corg.highwire.dtl.DTLVardef@1ef1e89org.highwire.dtl.DTLVardef@1bdc0a5_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

Myeloid mechano-metabolic programming restricts anti-tumor immunity

Tumor progression is accompanied by fibrosis, which is associated with diminished anti-tumor immune infiltrate. Here, we demonstrate that tumor infiltrating myeloid cells respond to the stiffened fibrotic tumor microenvironment (TME) by initiating a TGF-beta (TGF{beta})-directed, collagen biosynthesis program. A collateral effect of this programming is an untenable metabolic milieu for productive CD8 T cell anti-tumor responses, as collagen-synthesizing macrophages consume environmental arginine, synthesize proline, and secrete ornithine that compromises CD8+ T cell function. Thus, a stiff and fibrotic TME may impede anti-tumor immunity not only by direct physical exclusion of CD8+ T cells, but also via secondary effects of a myeloid mechano-metabolic programming we identified that creates an inhospitable metabolic milieu for CD8+ T cells.

cancer biology↗

Mechanosensitive hormone signaling promotes mammary progenitor expansion and breast cancer progression

Tissue stem-progenitor cell frequency has been implicated in tumor risk and progression. Tissue-specific factors linking stem-progenitor cell frequency to cancer risk and progression remain ill defined. Using a genetically engineered mouse model that promotes integrin mechanosignaling with syngeneic manipulations, spheroid models, and patient-derived xenografts we determined that a stiff extracellular matrix and high integrin mechanosignaling increase stem-progenitor cell frequency to enhance breast tumor risk and progression. Studies revealed that high integrin-mechanosignaling expands breast epithelial stem-progenitor cell number by potentiating progesterone receptor-dependent RANK signaling. Consistently, we observed that the stiff breast tissue from women with high mammographic density, who exhibit an increased lifetime risk for breast cancer, also have elevated RANK signaling and a high frequency of stem-progenitor epithelial cells. The findings link tissue fibrosis and integrin mechanosignaling to stem-progenitor cell frequency and causally implicate hormone signaling in this phenotype. Accordingly, inhibiting RANK signaling could temper the tumor promoting impact of fibrosis on breast cancer and reduce the elevated breast cancer risk exhibited by women with high mammographic density. SummaryElevated mechano-signaling and matrix stiffness promote progesterone and RANK mediated expansion of mammary progenitors and breast cancer risk and progression.

cancer biology↗