Chondrocytes in mice developing osteoarthritis (OA) exhibit an aberrant response to the secreted cytokine transforming growth factor (TGF)-beta, consisting in a potentiation of intracellular... Show moreChondrocytes in mice developing osteoarthritis (OA) exhibit an aberrant response to the secreted cytokine transforming growth factor (TGF)-beta, consisting in a potentiation of intracellular signaling downstream of the transmembrane type I receptor kinase activin receptor-like kinase (ALK)1 against canonical TGF-beta receptor ALK5-mediated signaling. Unfortunately, the underlying mechanisms remain elusive. In order to identify novel druggable targets for OA, we aimed to investigate novel molecules regulating the ALK1/ALK5 balance in OA chondrocytes. We performed gene expression analysis of TGF-beta signaling modulators in joints from three different mouse models of OA and found an upregulated expression of the TGF-beta co-receptor Cripto (Tdgf1), which was validated in murine and human cartilage OA samples at the protein level. In vitro and ex vivo, elevated expression of Cripto favors the hypertrophic differentiation of chondrocytes, eventually contributing to tissue calcification. Furthermore, we found that Cripto participates in a TGF-beta-ALK1-Cripto receptor complex in the plasma membrane, thereby inducing catabolic SMAD1/5 signaling in chondrocytes. In conclusion, we demonstrate that Cripto is expressed in OA and plays a functional role promoting chondrocyte hypertrophy, thereby becoming a novel potential therapeutic target in OA, for which there is no efficient cure or validated biomarker. (C) 2021 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland. Show less
Ventura, F.; Williams, E.; Ikeya, M.; Bullock, A.N.; Dijke, P. ten; Goumans, M.J.; Sanchez Duffhues, G. 2021
Fibrodysplasia ossificans progressiva (FOP) is an ultrarare congenital disease that progresses through intermittent episodes of bone formation at ectopic sites. FOP patients carry heterozygous gene... Show moreFibrodysplasia ossificans progressiva (FOP) is an ultrarare congenital disease that progresses through intermittent episodes of bone formation at ectopic sites. FOP patients carry heterozygous gene point mutations in activin A receptor type I ACVR1, encoding the bone morphogenetic protein (BMP) type I serine/threonine kinase receptor ALK2, termed activin receptor-like kinase (ALK)2. The mutant ALK2 displays neofunctional responses to activin, a closely related BMP cytokine that normally inhibits regular bone formation. Moreover, the mutant ALK2 becomes hypersensitive to BMPs. Both these activities contribute to enhanced ALK2 signalling and endochondral bone formation in connective tissue. Being a receptor with an extracellular ligand-binding domain and intrinsic intracellular kinase activity, the mutant ALK2 is a druggable target. Although there is no approved cure for FOP yet, a number of clinical trials have been recently initiated, aiming to identify a safe and effective treatment for FOP. Among other targeted approaches, several repurposed drugs have shown promising results. In this review, we describe the molecular mechanisms underlying ALK2 mutation-induced aberrant signalling and ectopic bone formation. In addition, we recapitulate existing in vitro models to screen for novel compounds with a potential application in FOP. We summarize existing therapeutic alternatives and focus on repositioned drugs in FOP, at preclinical and clinical stages. Show less
TGF beta-SMAD3 signaling is a major driving force for cancer metastasis, while BMP-SMAD1/5 signaling can counteract this response. Analysis of gene expression profiles revealed that an increased... Show moreTGF beta-SMAD3 signaling is a major driving force for cancer metastasis, while BMP-SMAD1/5 signaling can counteract this response. Analysis of gene expression profiles revealed that an increased TGF beta-SMAD3 and a reduced BMP-SMAD1/5 targeted gene expression signature correlated with shortened distant metastasis free survival and overall survival of patients. At molecular levels, we discovered that TGF beta abolished BMP-induced SMAD1/5 activation in the highly-invasive breast cancer MDA-MB-231 cells, but to a less extent in the non-invasive cancer and normal breast cells. This suggests an inverse correlation between BMP signaling and invasiveness of tumor cells and TGF beta signaling acts in a double whammy fashion in driving cancer invasion and metastasis. Sustained ERK activation by TGF beta was specifically observed in MDA-MB-231 cells, and MEK inhibitor (MEKi) treatment restored BMP-SMAD1/5 signaling while not affecting SMAD2/3 activation. FK506 potently activated BMP, but not TGF beta signaling in breast cancer cells. MEKi or FK506 alone inhibited MDA-MB-231 extravasation in a zebrafish xenograft cancer model. Importantly, when administrated at suboptimal concentrations MEKi and FK506 strongly synergized in promoting BMP-SMAD1/5 signaling and inhibiting cancer cell extravasation. Furthermore, this combination of suboptimal concentrations treatment in a mouse tumor model resulted in real-time reduction of BMP-SMAD1/5 signaling in live tumors, and consequently potently inhibited tumor self-seeding, liver and bone metastasis, but not lung and brain metastasis. Mechanistically, it is the first time to identify BMP-SMAD1/5 signaling as an underlying molecular driver for organ-specific metastasis. Combining of MEKi and FK506, or their analogues, may be explored for clinical development of breast cancer. Show less
We set out the get a better understanding of the role of Bone Morphogenetic Protein(BMP) signalling in normal intestine and in carcinogenesis. The BMP pathway isknown to be a major player in the... Show moreWe set out the get a better understanding of the role of Bone Morphogenetic Protein(BMP) signalling in normal intestine and in carcinogenesis. The BMP pathway isknown to be a major player in the development of colorectal cancer (CRC). CRC isone of the leading causes of cancer-related deaths in the western world. Althoughsurvival and recurrence of CRC have improved, 5-year survival is low at only 65%(https://seer.cancer.gov – US data). Improving our understanding of the molecularpathways involved in CRC will potentially allow earlier detection, better predictionand personalized therapy. To briefly summarise the research we have done, we startedby investigating the function of BMP in the normal intestine. We then went on tostudy the role of BMP signalling in carcinogenesis, mainly the role of non canonicalBMP signalling in the development of metastasis. We ended with a focus on patientsby explaining how we can improve estimation of prognosis using expression levelsof several BMP components and how targeting the BMP pathway can be used forpersonalized treatment of patients. Show less
Sanchez Duffhues, G.; Williams, E.; Goumans, M.J.; Heldin, C.H.; Dijke, P. ten 2020
Bone morphogenetic proteins (BMPs) are secreted cytokines that control the fate and function of many different cell types. They exert their cellular responses via heteromeric complexes of specific... Show moreBone morphogenetic proteins (BMPs) are secreted cytokines that control the fate and function of many different cell types. They exert their cellular responses via heteromeric complexes of specific BMP type I and type II serine/threonine kinase receptors, e.g. BMPRIA and BMPRII. Three type II and four type I receptors, also termed activin receptor-like kinases (ALKs), have been identified. The constitutively active type II kinase phosphorylates the type I receptor, which upon activation initiates intracellular signaling by phosphorylating SMAD effectors. Auxiliary cell surface receptors without intrinsic enzymatic motifs, such as Endoglin and Repulsive guidance molecules (RGM), can fine-tune signaling by regulating the interaction of the BMP ligands with the BMPRs. The functional annotation of the BMPR encoding genes has helped to understand underlying mechanisms of diseases in which these genes are mutated. Loss of function mutations in BMPRII, Endoglin or RGMc are causally linked to pulmonary arterial hypertension, hereditary hemorrhagic telangiectasia and juvenile hemochromatosis, respectively. In contrast, gain of function mutations in ACVR1, encoding ALK2, are linked to Fibrodysplasia ossificans progressiva and diffuse intrinsic pontine glioma. Here, we discuss BMPR identification, structure and function in health and disease. Moreover, we highlight the therapeutic promise of small chemical compounds that act as selective BMPR kinase inhibitors to normalize overactive BMPR signaling. Show less
This thesis elucidated the possibility of manipulating BMP/TGFβ signaling to achieve inhibition of breast cancer metastasis, including boosting BMP signaling via blockade of the BMP antagonist... Show moreThis thesis elucidated the possibility of manipulating BMP/TGFβ signaling to achieve inhibition of breast cancer metastasis, including boosting BMP signaling via blockade of the BMP antagonist Grem1 extracellularly or via stimulation of small-molecule compounds intracellularly, preventing TGFβ signaling to allow accumulation of pro-oncogenic stimuli. We also highlight the importance of selecting appropriate cancer types when adopting dual inhibition of PD-L1 and TGFβ signaling. I hope my research will aid in more efficient clinical cancer therapies. Show less
The epicardium, the outer layer of the heart, has been of interest in cardiac research due to its vital role in the developing and diseased heart. During development, epicardial cells are active... Show moreThe epicardium, the outer layer of the heart, has been of interest in cardiac research due to its vital role in the developing and diseased heart. During development, epicardial cells are active and supply cells and paracrine cues to the myocardium. In the injured adult heart, the epicardium is re-activated and recapitulates embryonic behavior that is essential for a proper repair response. Two indispensable processes for epicardial contribution to heart tissue formation are epithelial to mesenchymal transition (EMT), and tissue invasion. One of the key groups of cytokines regulating both EMT and invasion is the transforming growth factor beta (TGF beta) family, including TGF beta and Bone Morphogenetic Protein (BMP). Abundant research has been performed to understand the role of TGF beta family signaling in the developing epicardium. However, less is known about signaling in the adult epicardium. This review provides an overview of the current knowledge on the role of TGF beta in epicardial behavior both in the development and in the repair of the heart. We aim to describe the presence of involved ligands and receptors to establish if and when signaling can occur. Finally, we discuss potential targets to improve the epicardial contribution to cardiac repair as a starting point for future investigation. Show less
Hereditary hemorrhagic telangiectasia (HHT) or Rendu-Osler-Weber disease, is a rare genetic disorder, known for its endothelial dysplasia causing vessel malformations, severe nose bleeds and... Show moreHereditary hemorrhagic telangiectasia (HHT) or Rendu-Osler-Weber disease, is a rare genetic disorder, known for its endothelial dysplasia causing vessel malformations, severe nose bleeds and internal bleedings. In the majority of patients mutations are found in genes belonging to the TGFβ superfamily, causing a disbalance in the TGFβ signaling pathway by haploinsufficiency of the remaining functional protein. In this thesis we studied different aims and approaches to influence HHT1-MNC homing and differentiation to restore their contribution to tissue repair. In various experimental methods inducing ischemic and/or direct tissue damage, we aimed to improve tissue repair in the Eng+/- mice. Using DPP4 inhibition, we increased the SDF1-CXCR4 homing mechanism, to restore the impaired homing capacity of the HHT1-MNCs. Furthermore, we focused on correcting the M1/M2 differentiation in Eng+/- mice. Via use of the BMP receptor inhibitor LDN we aimed to restore the skewed BMP/TGFβ signaling; stimulating the TGFβ pathway signaling to induce M2 differentiation. We concluded that DPP4 inhibition can be used to improve the HHT1 immune system and tissue repair, and is best used in concert with other drugs or therapies that stimulate cardiac or tissue repair, like anti-coagulants or cell therapy. Show less
Gomez-Puerto, M.C.; Iyengar, P.V.; Vinuesa, A.G. de; Dijke, P. ten; Sanchez-Duffhues, G. 2019
Cancer and fibrosis are devastating diseases of high mortality rate and with limited curative therapies available. A better understanding of the biological drivers of these diseases is fundamental... Show moreCancer and fibrosis are devastating diseases of high mortality rate and with limited curative therapies available. A better understanding of the biological drivers of these diseases is fundamental in order to develop effective therapeutics. At the molecular level, signaling pathways control cell growth, differentiation or apoptosis during development and adult life of the organism ensuring homeostasis. Paradoxically, the same signals are often implicated or even drive disease progression. One of the signaling pathways with key regulatory functions in homeostasis, tissue fibrosis and cancer in many organs is the TGFβ/BMP pathway. In this thesis we addressed the role and therapeutic potential of TGFβ/BMP pathway inhibition using different drug compounds that are currently towards the clinic or being tested in clinical trials. Three distinct types of inhibitors were used; small molecule inhibitors of the ALK4, 5 and 7 TGFβ receptor kinases, an antisense oligonucleotide interfering with ALK5 mRNA splicing and an ALK1 ligand trap; a peptide that contains the extracellular domain of ALK1 fused to Fc and sequesters BMP9 and BMP10. These inhibitors were used in an ex vivo human fibrosis model and in vivo mouse models of various human diseases (acute liver failure/ liver regeneration, Dupuytren's fibrosis) and cancer (prostate, liver). Show less
The transforming growth factor (TGF)-_ signalling pathway plays a major role in angiogenesis. Aberration of the TGF-_ signalling cascade leads to abnormal remodelling and maturation of the... Show moreThe transforming growth factor (TGF)-_ signalling pathway plays a major role in angiogenesis. Aberration of the TGF-_ signalling cascade leads to abnormal remodelling and maturation of the primitive vascular plexus and decreased vessel wall integrity in adults. Targeted deletion of TGF-_ signalling receptors in mice, such as ALK1, ALK5, T_RII or endoglin, results in embryonic lethality due to impaired vascular development. In humans, mutations in ALK1, ALK5, T_RII or endoglin are associated with human vascular diseases such as HHT and pulmonary hypertension (PAH). Vascular endothelial growth factor (VEGF) is a multifunctional molecule that is involved in vascular growth and remodeling. Perturbation in VEGF signalling also contributes to the pathology of tumor angiogenesis and cardiovascular diseases in humans. This thesis is focused on the characterization of the crosstalk between the TGF-_ and VEGF signalling pathways, on EC function, the effect of bone morphogenetic protein (BMP)9 on EC function and the role of endoglin in VEGF-induced angiogenesis. The results of these studies may give us insights into the impacts/effects of these two angiogenic signalling cascades on EC function. This can be beneficial for the understanding of the etiology of certain vascular diseases and the development of new treatment modalities in the future Show less
Zhang, X.F.; Zhang, J.; Bauer, A.; Zhang, L.; Selinger, D.W.; Lu, C.X.; Dijke, P. ten 2013