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Background: Radical cystectomy with pelvic lymph node dissection is the recommended treatment in non-metastatic muscle-invasive bladder cancer (MIBC). In randomised trials, robot-assisted radical cystectomy (RARC) showed non-inferior short-term oncological outcomes compared with open radical cystectomy (ORC). Data on intermediate and long-term oncological outcomes of RARC are limited. Objective: To assess the intermediate-term overall survival (OS) and recurrence-free survival (RFS) of patients with MIBC and high-risk non-MIBC (NMIBC) who underwent ORC versus RARC in clinical practice. Methods and materials: A nationwide retrospective study in 19 Dutch hospitals including patients with MIBC and high-risk NMIBC treated by ORC (n = 1086) or RARC (n = 386) between January 1, 2012 and December 31, 2015. Primary and secondary outcome measures were median OS and RFS, respectively. Survival outcomes were estimated using Kaplan-Meier curves. A multivariable Cox regression model was developed to adjust for possible confounders and to assess prognostic factors for survival including clinical variables, clinical and pathological disease stage, neoadjuvant therapy and surgical margin status. Results: The median follow-up was 5.1 years (95% confidence interval ([95%CI] 5.0–5.2). The median OS after ORC was 5.0 years (95%CI 4.3–5.6) versus 5.8 years after RARC (95%CI 5.1–6.5). The median RFS was 3.8 years (95%CI 3.1–4.5) after ORC versus 5.0 years after RARC (95%CI 3.9–6.0). After multivariable adjustment, the hazard ratio for OS was 1.00 (95%CI 0.84–1.20) and for RFS 1.08 (95%CI 0.91–1.27) of ORC versus RARC. Patients who underwent ORC were older, had higher preoperative serum creatinine levels and more advanced clinical and pathological disease stage. Conclusion: ORC and RARC resulted in similar intermediate-term OS and RFS in a cohort of almost 1500 MIBC and high-risk NMIBC.

Acute megakaryoblastic leukemia (AMKL) is a subtype of acute myeloid leukemia (AML) in which cells morphologically resemble abnormal megakaryoblasts. While rare in adults, AMKL accounts for 4-15% of newly diagnosed childhood AML cases. AMKL in individuals without Down syndrome (non-DS-AMKL) is frequently associated with poor clinical outcomes. Previous efforts have identified chimeric oncogenes in a substantial number of non-DS-AMKL cases, including RBM15-MKL1, CBFA2T3-GLIS2, KMT2A gene rearrangements, and NUP98-KDM5A. However, the etiology of 30-40% of cases remains unknown. To better understand the genomic landscape of non-DS-AMKL, we performed RNA and exome sequencing on specimens from 99 patients (75 pediatric and 24 adult). We demonstrate that pediatric non-DS-AMKL is a heterogeneous malignancy that can be divided into seven subgroups with varying outcomes. These subgroups are characterized by chimeric oncogenes with cooperating mutations in epigenetic and kinase signaling genes. Overall, these data shed light on the etiology of AMKL and provide useful information for the tailoring of treatment.

Genetic abnormalities and early treatment response are the main prognostic factors in acute myeloid leukemia (AML). Acute megakaryoblastic leukemia (AMKL) is a rare subtype of AML. Deep sequencing has identified CBFA2T3/GLIS2 and NUP98/KDM5A as recurrent aberrations, occurring in similar frequencies as RBM15/MKL1 and KMT2A-rearrangements. We studied whether these cytogenetic aberrations can be used for risk group stratification. To assess frequencies and outcome parameters of recurrent cytogenetic aberrations in AMKL, samples and clinical data of patients treated by the Associazione Italiana Ematologia Oncologia Pediatrica, Berlin-Frankfurt-Munster Study Group, Children's Oncology Group, Dutch Childhood Oncology Group, and the Saint Louis Hôpital were collected, enabling us to screen 153 newly diagnosed pediatric AMKL cases for the aforementioned aberrations and to study their clinical characteristics and outcome. CBFA2T3/GLIS2 was identified in 16% of the cases; RBM15/MKL1, in 12%; NUP98/KDM5A and KMT2A rearrangements, in 9% each; and monosomy 7, in 6%. These aberrations were mutually exclusive. RBM15/MKL1-rearranged patients were significantly younger. No significant differences in sex and white blood cell count were found. NUP98/KDM5A, CBFA2T3/GLIS2, KMT2A-rearranged lesions and monosomy 7 (NCK-7) independently predicted a poor outcome, compared with RBM15/MKL1-rearranged patients and those with AMKL not carrying these molecular lesions. NCK-7-patients (n = 61) showed a 4-year probability of overall survival of 35 ± 6% vs 70 ± 5% in the RBM15/MKL1-other groups (n = 92, P < .0001) and 4-year probability of event-free survival of 33 ± 6% vs 62 ± 5% (P = .0013), the 4-year cumulative incidence of relapse being 42 ± 7% and 19 ± 4% (P = .003), respectively. We conclude that these genetic aberrations may be used for risk group stratification of pediatric AMKL and for treatment tailoring.

In multicellular organisms control over organ size and shape is of utter importance. However, the regulation of control is rather complex. An involved signalling route is the Hippo pathway. In this review, the core cascade and downstream target of the Hippo pathway will be discussed. The first components of the pathway, Warts, Salvador, Hippo and Mats, were discovered in a search for tumour suppressors in the fruitfly (Drosophila melanogaster). The downstream target is the transcription co-activator Yorkie (YKI), which targets many genes implicated in proliferation and apoptosis. These processes are involved in growth control. Deregulation can, therefore, result in severe effects, such as tumourigenesis. Furthermore, the upstream regulators of the Hippo pathway will be disclosed. Various factors are shown to regulate the Hippo pathway core kinases and/or Yorkie. The vastness of the upstream regulators is required for tissue, timing and organism specificity. In order for the Hippo pathway to affect the overall tissue, communication between cells is necessary. Therefore, cell-cell interactions are required to tightly control and modulate Hippo activity between neighbouring cells. Cross talk between the Hippo pathway and other mechanisms is necessary to coordinate the complex development and homeostasis of tissue size, shape and patterning. Taken together, the Hippo pathway is important for processes, such as proliferation and apoptosis. Even though, the regulation of the pathway is understood more and more, research is required to elucidate the signalling route even further. Since deregulation of the pathway can result in tumour formations, better understanding of the pathway could help better understand tumour development and progression. Moreover, insights in the signalling route might help develop therapeutic targets for cancer and other diseases.

Mechanical forces are increasingly recognized as central factors in the regulation of tissue morphogenesis and homeostasis. Central to the transduction of mechanical information into biochemical signaling is the contractile actomyosin cytoskeleton. Fluctuations in actomyosin contraction are sensed by tension sensitive systems at the interface between actomyosin and cell adhesion complexes. We review the current knowledge about the mechanical coupling of cell-cell junctions to the cytoskeleton and highlight the central role of alpha-catenin in this linkage. We assemble current knowledge about alpha-catenin's regulation by tension and about its interactions with a diversity of proteins. We present a model in which alpha-catenin is a force-regulated platform for a machinery of proteins that orchestrates local cortical remodeling in response to force. Finally, we highlight recently described fundamental processes in tissue morphogenesis and argue where and how this alpha-catenin-dependent cadherin mechanotransduction may be involved., Mechanical forces are increasingly recognized as central factors in the regulation of tissue morphogenesis and homeostasis. Central to the transduction of mechanical information into biochemical signaling is the contractile actomyosin cytoskeleton. Fluctuations in actomyosin contraction are sensed by tension sensitive systems at the interface between actomyosin and cell adhesion complexes. We review the current knowledge about the mechanical coupling of cell-cell junctions to the cytoskeleton and highlight the central role of alpha-catenin in this linkage. We assemble current knowledge about alpha-catenin's regulation by tension and about its interactions with a diversity of proteins. We present a model in which alpha-catenin is a force-regulated platform for a machinery of proteins that orchestrates local cortical remodeling in response to force. Finally, we highlight recently described fundamental processes in tissue morphogenesis and argue where and how this alpha-catenin-dependent cadherin mechanotransduction may be involved.

Cells integrate biochemical and mechanical information to function within multicellular tissue. Within developing and remodeling tissues, mechanical forces contain instructive information that governs important cellular processes that include stem cell maintenance, differentiation and growth. Although the principles of signal transduction (protein phosphorylation, allosteric regulation of enzymatic activity and binding sites) are the same for biochemical and mechanical-induced signaling, the first step of mechanosensing, in which protein complexes under tension transduce changes in physical force into cellular signaling, is very different, and the molecular mechanisms are only beginning to be elucidated. In this Commentary, we focus on mechanotransduction at cell-cell junctions, aiming to comprehend the molecular mechanisms involved. We describe how different junction structures are associated with the actomyosin cytoskeleton and how this relates to the magnitude and direction of forces at cell-cell junctions. We discuss which cell-cell adhesion receptors have been shown to take part in mechanotransduction. Then we outline the force-induced molecular events that might occur within a key mechanosensitive system at cell-cell junctions; the cadherin-F-actin interface, at which alpha-catenin and vinculin form a central module. Mechanotransduction at cell-cell junctions emerges as an important signaling mechanism, and we present examples of its potential relevance for tissue development and disease., Cells integrate biochemical and mechanical information to function within multicellular tissue. Within developing and remodeling tissues, mechanical forces contain instructive information that governs important cellular processes that include stem cell maintenance, differentiation and growth. Although the principles of signal transduction (protein phosphorylation, allosteric regulation of enzymatic activity and binding sites) are the same for biochemical and mechanical-induced signaling, the first step of mechanosensing, in which protein complexes under tension transduce changes in physical force into cellular signaling, is very different, and the molecular mechanisms are only beginning to be elucidated. In this Commentary, we focus on mechanotransduction at cell-cell junctions, aiming to comprehend the molecular mechanisms involved. We describe how different junction structures are associated with the actomyosin cytoskeleton and how this relates to the magnitude and direction of forces at cell-cell junctions. We discuss which cell-cell adhesion receptors have been shown to take part in mechanotransduction. Then we outline the force-induced molecular events that might occur within a key mechanosensitive system at cell-cell junctions; the cadherin-F-actin interface, at which alpha-catenin and vinculin form a central module. Mechanotransduction at cell-cell junctions emerges as an important signaling mechanism, and we present examples of its potential relevance for tissue development and disease.

By beautiful imaging and state-of-the-art experiments, vinculin is established to be a central switch in mechanotransduction at integrin-based focal adhesions. Cycles of tension-regulated vinculin switching control focal adhesion dynamics and signaling to enable polarized cell migration and alignment., By beautiful imaging and state-of-the-art experiments, vinculin is established to be a central switch in mechanotransduction at integrin-based focal adhesions. Cycles of tension-regulated vinculin switching control focal adhesion dynamics and signaling to enable polarized cell migration and alignment.

To remodel endothelial cell-cell adhesion, inflammatory cytokine- and angiogenic growth factor-induced signals impinge on the vascular endothelial cadherin (VE-cadherin) complex, the central component of endothelial adherens junctions. This study demonstrates that junction remodeling takes place at a molecularly and phenotypically distinct subset of VE-cadherin adhesions, defined here as focal adherens junctions (FAJs). FAJs are attached to radial F-actin bundles and marked by the mechanosensory protein Vinculin. We show that endothelial hormones vascular endothelial growth factor, tumor necrosis factor alpha, and most prominently thrombin induced the transformation of stable junctions into FAJs. The actin cytoskeleton generated pulling forces specifically on FAJs, and inhibition of Rho-Rock-actomyosin contractility prevented the formation of FAJs and junction remodeling. FAJs formed normally in cells expressing a Vinculin binding-deficient mutant of alpha-catenin, showing that Vinculin recruitment is not required for adherens junction formation. Comparing Vinculin-devoid FAJs to wild-type FAJs revealed that Vinculin protects VE-cadherin junctions from opening during their force-dependent remodeling. These findings implicate Vinculin-dependent cadherin mechanosensing in endothelial processes such as leukocyte extravasation and angiogenesis.

We developed new image analysis tools to analyse quantitatively the extracellular-matrix-dependent cell spreading process imaged by live-cell epifluorescence microscopy. Using these tools, we investigated cell spreading induced by activation of the small GTPase, Rap1. After replating and initial adhesion, unstimulated cells exhibited extensive protrusion and retraction as their spread area increased, and displayed an angular shape that was remodelled over time. In contrast, activation of endogenous Rap1, via 007-mediated stimulation of Epac1, induced protrusion along the entire cell periphery, resulting in a rounder spread surface, an accelerated spreading rate and an increased spread area compared to control cells. Whereas basal, anisotropic, spreading was completely dependent on Src activity, Rap1-induced spreading was refractory to Src inhibition. Under Src inhibited conditions, the characteristic Src-induced tyrosine phosphorylations of FAK and paxillin did not occur, but Rap1 could induce the formation of actomyosin-connected adhesions, which contained vinculin at levels comparable to that found in unperturbed focal adhesions. From these results, we conclude that Rap1 can induce cell adhesion and stimulate an accelerated rate of cell spreading through mechanisms that bypass the canonical FAK-Src-Paxillin signalling cascade., We developed new image analysis tools to analyse quantitatively the extracellular-matrix-dependent cell spreading process imaged by live-cell epifluorescence microscopy. Using these tools, we investigated cell spreading induced by activation of the small GTPase, Rap1. After replating and initial adhesion, unstimulated cells exhibited extensive protrusion and retraction as their spread area increased, and displayed an angular shape that was remodelled over time. In contrast, activation of endogenous Rap1, via 007-mediated stimulation of Epac1, induced protrusion along the entire cell periphery, resulting in a rounder spread surface, an accelerated spreading rate and an increased spread area compared to control cells. Whereas basal, anisotropic, spreading was completely dependent on Src activity, Rap1-induced spreading was refractory to Src inhibition. Under Src inhibited conditions, the characteristic Src-induced tyrosine phosphorylations of FAK and paxillin did not occur, but Rap1 could induce the formation of actomyosin-connected adhesions, which contained vinculin at levels comparable to that found in unperturbed focal adhesions. From these results, we conclude that Rap1 can induce cell adhesion and stimulate an accelerated rate of cell spreading through mechanisms that bypass the canonical FAK-Src-Paxillin signalling cascade.