Hepatocyte Growth Factor-mediated satellite cells niche perturbation promotes development of distinct sarcoma subtypes

Pathological roles of c-Met in bladder cancer: Association with cyclooxygenase-2, heme oxygenase-1, vascular endothelial growth factor-A and programmed death ligand 1

c-Met is a receptor tyrosine kinase that binds a specific ligand, namely hepatocyte growth factor (HGF). The HGF/c-Met system is important for malignant aggressiveness in various types of cancer, including bladder cancer (BC). However, although phosphorylation is the essential step required for biological activation of c-Met, pathological roles of phosphorylated c-Met at the clinical and molecular levels in patients with BC are not fully understood. In the present study, the expression levels of c-Met and the phosphorylation of two of its tyrosine residues (pY1234/pY1235 and pY1349) were immunohistochemically examined in 185 BC tissues. The associations between these expression levels and cancer cell invasion, metastasis, and cyclooxygenase-2 (COX-2), heme oxygenase-1 (HO-1), VEGF-A and programmed death ligand 1 (PD-L1) levels were investigated. c-Met was associated with muscle invasion (P=0.021), as well as the expression levels of HO-1 (P=0.028) and PD-L1 (P<0.001), whereas pY1349 c-Met was associated with muscle invasion (P=0.003), metastasis (P=0.025), and COX-2 (P=0.017), HO-1 (P=0.031) and PD-L1 (P=0.001) expression. By contrast, pY1234/1235 c-Met was associated with muscle invasion and metastasis (P=0.006 and P=0.012, respectively), but not with the panel of cancer-associated molecules. Furthermore, COX-2 and PD-L1 expression were associated with muscle invasion and metastasis, respectively (P=0.045 and P=0.036, respectively). Hence, c-Met serves important roles in muscle invasion by regulating HO-1 and PD-L1, whereas its phosphorylation at Y1349 is associated with muscle invasion and metastasis via the regulation of COX-2, HO-1 and PD-L1 in patients with BC. Furthermore, phosphorylation at Y1234/1235 may lead to muscle invasion and metastasis via alternate mechanisms associated with c-Met and pY1349 c-Met.

Near-Infrared Light-Activated DNA-Agonist Nanodevice for Nongenetically and Remotely Controlled Cellular Signaling and Behaviors in Live Animals

Optogenetics provides promising tools for the precise control of receptor-mediated cell behaviors in a spatiotemporal manner. Yet, most photoreceptors require extensive genetic manipulation and respond only to ultraviolet or visible light, which are suboptimal for in vivo applications because they do not penetrate thick tissues. Here we report a novel near-infrared light-activated DNA agonist (NIR-DA) nanodevice for nongenetic manipulation of cell signaling and phenotype in deep tissues. This nanodevice is prepared by conjugating a preinactivated DNA agonist onto the gold nanorods (AuNRs). Upon NIR light treatment, the DNA agonist is released through the localized surface plasmon resonance (LSPR)-based photothermal effect of AuNRs and becomes active. The active DNA agonist dimerizes the DNA-modified chimeric or native receptor tyrosine kinase (RTK) on cell surfaces and activates downstream signal transduction in live cells. Such NIR-DA activation of RTK signaling enables the control of cytoskeletal remodeling, cell polarization, and directional migration. Furthermore, we demonstrate that the NIR-DA system can be used in vivo to mediate RTK signaling and skeletal muscle satellite cell migration and myogenesis, which are critical cellular behaviors in the process of skeletal muscle regeneration. Thus, the NIR-DA system offers a powerful and versatile platform for exogenous modulation of deep tissues for purposes such as regenerative medicine.