Paxillin is a well-known multidomain scaffold protein that is involved in the regulation of cell-matrix adhesiondynamics, a process required for the tumor cell migration and invasion.... Show morePaxillin is a well-known multidomain scaffold protein that is involved in the regulation of cell-matrix adhesiondynamics, a process required for the tumor cell migration and invasion. Phosphorylation of the serine residue 178requires c-Jun NH2-terminal kinase (JNK) activation, which occurs downstream of epidermal growth factor receptor (EGFR)-mediated signaling and drives cell migration. In this study, we investigated the significance of paxillin Ser178 phosphorylation in breast cancer progression.We employed the rat mammary carcinoma MTLn3 cell line with which we established stabile variants of both wild type and mutant GFP-paxillin constructs. With those, we next performed several in vitro assays including cell proliferation, migration and focal adhesion dynamics. Finally, we monitored the metastatic spread of both cell line variants in an othrotopic mouse model for breast cancer.Here we show that expression of the phospho-defective mutant paxillinS178A in the metastatic mammary adenocarcinoma MTLn3 cell-line significantly decreased EGF-induced cell migration, which was correlated with impaired focal adhesion dynamics. Moreover, paxillinS178A attenuated lung metastasis formation in an orthotopic in vivo mammary gland tumor/metastasis model, demonstrating the importance of JNK-mediated paxillin phosphorylation in breast cancer progression. Expression of paxillinS178A caused a decrease in EGFR expression while re-expression of EGFR in MTLn3-paxillinS178A cells fully restored EGF-driven cell motility and focal adhesion dynamics. Furthermore, re-expression of EGFR in MTLn3-paxillinS178A rescued spontaneous metastasis from breast to lung.Overall our data show an important role for JNK-mediated paxillin Ser178 phosphorylation in the regulation of EGFR expression and thereby, in EGF-driven cell migration and metastasis formation. Show less
Smolle, M.A.; Praag, V.M. van; Posch, F.; Bergovec, M.; Leitner, L.; Friesenbichler, J.; ... ; Leithner, A. 2019
This thesis describes i) the function of an alternatively spliced coagulation factor in hemostasis, ii) the contribution of coagulation factors on cancer progression, and iii) expands our view... Show moreThis thesis describes i) the function of an alternatively spliced coagulation factor in hemostasis, ii) the contribution of coagulation factors on cancer progression, and iii) expands our view on cancer-associated thrombosis. Inhibition of Tissue Factor (TF) signaling with the antibody (Mab-10H10) resulted in decreased tumor initiating capacity and metastasis in a triple negative breast cancer (TNBC) cell line. Since this is a tumor type that is difficult to treat, and has high relapse-rates, it would be of interest to target TF signaling. Dual treatment of TNBC with conventional chemotherapy and Mab-10H10 could result in a positive treatment strategy as both highly proliferative and cancer stem cells are targeted. Furthermore, we provided a proof-of-principle study to search for novel biomarkers in patients with cancer-associated thrombosis in an unbiased manner. Up till now it is challenging to accurately predict those cancer patients with elevated risk of thrombosis. Furthermore, patients with cancer-associated thrombosis have poorer survival. Expansion of this study to validation cohorts and other tumor types will give insights in the underlying molecular mechanism of cancer-associated thrombosis. Eventually, this will aid a better prediction model to select those cancer patients with high risk of thrombosis and those who might benefit from thromboprophylaxis. Show less
Cells receive mechanical cues from the surrounding extracellular matrix (ECM). This has a strong impact on physiology and pathology in a wide range of biological settings. Integrin receptors couple... Show moreCells receive mechanical cues from the surrounding extracellular matrix (ECM). This has a strong impact on physiology and pathology in a wide range of biological settings. Integrin receptors couple the ECM to the intracellular cytoskeleton across the cell membrane through a dynamic multiprotein adhesion complex and mediate bidirectional force transmission. In this research the mechanism of cellular mechanotransduction and its role in aspects of cancer progression are studied, focusing on integrins and other integrin associated proteins. We find that the integrin expression profile of cells regulates the orientation and dynamics of force transmission at cell-matrix adhesions. Additionally, using a novel method to quantify the abundance of a molecule in a cellular complex, we show that substrate rigidity modulates the association between traction forces and molecular composition of cell-matrix adhesions. Using cell microprinting in 3D ECM scaffolds, we determine the relation between tumor-induced remote ECM network orientation and angiogenesis. Lastly, genes that regulate cancer cell migration, force application, and adhesion dynamics are identified. Overall, the work described in this thesis unravels the role of cellular mechanotransduction in different aspects of cancer progression and reveals how the molecular composition of cell-matrix adhesions relates to traction force generation. Show less
Introduction Metastatic spinal cancer is a common condition that may lead to spinal instability, pain and paralysis. In the 1980s, surgery was discouraged because results showed worse neurological... Show moreIntroduction Metastatic spinal cancer is a common condition that may lead to spinal instability, pain and paralysis. In the 1980s, surgery was discouraged because results showed worse neurological outcomes and pain compared with radiotherapy alone. However, with the advent of modern imaging and spinal stabilisation techniques, the role of surgery has regained centre stage, though few studies have assessed quality of life and functional outcomes after surgery. Objective We investigated whether surgery provides sustained improvement in quality of life and pain relief for patients with symptomatic spinal metastases by analysing the largest reported surgical series of patients with epidural spinal metastases. Methods A prospective cohort study of 922 consecutive patients with spinal metastases who underwent surgery, from the Global Spine Tumour Study Group database. Pre- and post-operative EQ-5D quality of life, visual analogue pain score, Karnofsky physical functioning score, complication rates and survival were recorded. Results Quality of life (EQ-5D), VAS pain score and Karnofsky physical functioning score improved rapidly after surgery and these improvements were sustained in those patients who survived up to 2 years after surgery. In specialised spine centres, the technical intra-operative complication rate of surgery was low, however almost a quarter of patients experienced post-operative systemic adverse events. Conclusion Surgical treatment for spinal metastases produces rapid pain relief, maintains ambulation and improves good quality of life. However, as a group, patients with cancer are vulnerable to post-operative systemic complications, hence the importance of appropriate patient selection. Show less
Ewing sarcoma (ES) is a special type of bone cancer, first described by Dr. James Ewing in his paper __Diffusive endothelioma of bone__. Today Ewing sarcoma represents the second most common bone... Show moreEwing sarcoma (ES) is a special type of bone cancer, first described by Dr. James Ewing in his paper __Diffusive endothelioma of bone__. Today Ewing sarcoma represents the second most common bone cancer among adolescents and young adults. Contrary to the positive achievement in treatment of localized tumors, the long-term (5-years) survival for Ewing sarcoma patients with metastasis, however, remain below the 30% mark. In this thesis a report on experimental work aiming for a better understanding of the mechanisms underlying Ewing sarcoma metastasis is presented. Two distinct mechanisms are investigated: (1) a biochemical approach in which the initial steps in the CXCR4 signaling cascade are followed, and (2) a biophysical approach in which the guidance of Ewing sarcoma metastasis by the stiffness of their microenvironment is demonstrated. The results presented in this thesis provide deeper insights into the mechanisms controlling signaling of the chemokine receptor CXCR4 and into the role of the micro-environment in Ewing sarcoma cells behavior.Through various experimental approaches it was shown that both biochemical and biophysical guidance control how Ewing sarcoma develops into its distinct metastatic phenotype. Show less
We have developed novel fluorescence bio-imaging based automated models to screen for novel candidate targets involved in prostate cancer metastasis. Utilizing these models and adopting a... Show moreWe have developed novel fluorescence bio-imaging based automated models to screen for novel candidate targets involved in prostate cancer metastasis. Utilizing these models and adopting a functional genomics based approach; we identified SYK as a novel regulator of prostate cancer progression. We also identified functional involvement of MST1R in regulating the progression of prostate cancer. For both of these targets, there is supporting human clinical data to validate our results in prostate cancer. Show less
Mohseny, A.B.; Cai, Y.P.; Kuijjer, M.; Xiao, W.; Akker, B. van den; Andrea, C.E. de; ... ; Cleton-Jansen, A.M. 2012
Despite extensive studies to unravel molecular mechanisms underlying breast cancer metastasis, still 3500 women die of the results of this disease in the Netherlands each year. Improving our... Show moreDespite extensive studies to unravel molecular mechanisms underlying breast cancer metastasis, still 3500 women die of the results of this disease in the Netherlands each year. Improving our understanding of metastasis formation remains a challenge for further drug development. The scope of this thesis is the identification of novel candidate metastasis genes, with a main focus on candidate genes affecting tumor cell migration. For that purpose, a live cell imaging-based random cell migration assay that is suitable for screening has been developed. In addition, a mouse breast cancer model that allows to study tumor cell autonomous processes of metastasis formation is described. A RNA-interference tumor cell migration screen has been done and resulted in the identification of novel regulators of tumor cell migration that show clinical relevance in a breast cancer patient cohort. In addition, focused research has been conducted on two previously identified candidate metastasis genes to determine their role in breast cancer metastasis. Show less
