The fibroblast growth factor receptor family members, FGFR1-4, are frequently overexpressed in various solid tumors, including breast cancer and sarcomas. This overexpression highlights the potential of the family of FGFRs as promising targets for cancer therapy. However, conventional FGFR kinase inhibitors often encounter challenges such as limited efficacy or drug resistance. In this study, we pursue an alternative strategy by designing a conjugate of the FGFR ligand FGF1 with the radioisotope 161Tb, for targeted therapy in FGFR-overexpressing cancer cells. FGF1 was engineered (eFGF1) to incorporate a single cysteine at the C terminus for site-specific labeling with a DOTA chelator. eFGF1-DOTA was mixed with the radioisotope 161Tb under mild conditions, resulting in a labeling efficiency above 90%. The nonradioactive ligands were characterized by mass spectrometry, while radioligands were characterized by thin-layer chromatography. The targeting function of the radioligands was assessed through confocal microscopy, flow cytometry, and Western blot analysis, focusing on binding to cancer cells and the activation of downstream signaling pathways related to FGFR. When compared to MCF-7 and RD cell lines with low FGFR expression, eFGF1-DOTA-Tb[161Tb] radioligands demonstrated significantly higher accumulation in FGFR-overexpressing cell lines (MCF-7 FGFR1 and RMS559), leading to enhanced cytotoxicity. Besides radionuclides, eFGF1 can also deliver doxorubicin (DOX) into cancer cells. Considering these characteristics, eFGF1-DOTA-Tb[161Tb] and eFGF1-DOX emerge as promising candidates for FGFR-targeted cancer therapy, and further evaluation in vivo is warranted.

• Publikační typ
• časopisecké články MeSH

Receptor tyrosine kinases (RTKs) are membrane receptors that regulate many fundamental cellular processes. A tight regulation of RTK signaling is fundamental for development and survival, and an altered signaling by RTKs can cause cancer. RTKs are localized at the plasma membrane (PM) and the major regulatory mechanism of signaling of RTKs is their endocytosis and degradation. In fact, RTKs at the cell surface bind ligands with their extracellular domain, become active, and are rapidly internalized where the temporal extent of signaling, attenuation, and downregulation are modulated. However, other mechanisms of signal attenuation and termination are known. Indeed, inhibition of RTKs' activity may occur through the modulation of the phosphorylation state of RTKs and the interaction with specific proteins, whereas antagonist ligands can inhibit the biological responses mediated by the receptor. Another mechanism concerns the expression of endogenous inactive receptor variants that are deficient in RTK activity and take part to inactive heterodimers or hetero-oligomers. The downregulation of RTK signals is fundamental for several cellular functions and the homeostasis of the cell. Here, we will review the mechanisms of signal attenuation and termination of RTKs, focusing on FGFRs.

• Klíčová slova
• FGFRs, PTPs, RTKs, degradation, kinases, termination of signaling, ubiquitination,
• MeSH
• down regulace MeSH
• lidé MeSH
• lyzozomy metabolismus   MeSH
• mutace genetika   MeSH
• signální transdukce * MeSH
• tyrosinkinasové receptory antagonisté a inhibitory   genetika   metabolismus   MeSH
• ubikvitinace MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• tyrosinkinasové receptory MeSH

OBJECTIVE: Statins are widely used drugs for cholesterol lowering, which were recently found to counteract the effects of aberrant fibroblast growth factor receptor (FGFR3) signaling in cell and animal models of FGFR3-related chondrodysplasia. This opened an intriguing therapeutic possibility for human dwarfing conditions caused by gain-of-function mutations in FGFR3, although the mechanism of statin action on FGFR3 remains unclear. Here, we determine the effect of statins on FGFR signaling in chondrocytes. DESIGN: Cultured chondrocyte cell lines, mouse embryonic tibia cultures and limb bud micromasses were treated with FGF2 to activate FGFR signaling. The effects of atorvastatin, fluvastatin, lovastatin and pravastatin on FGFR3 protein stability and on FGFR-mediated chondrocyte growth-arrest, loss of extracellular matrix (ECM), induction of premature senescence and hypertrophic differentiation were evaluated. RESULTS: Statins did not alter the level of FGFR3 protein expression nor produce any effect on FGFR-mediated inhibition of chondrocyte proliferation and hypertrophic differentiation in cultured chondrocyte cell lines, mouse tibia cultures or limb bud micromasses. CONCLUSION: We conclude that statins do not inhibit the FGFR signaling in chondrocytes. Therefore the statin-mediated rescue of FGFR3-related chondrodysplasia, described before, is likely not intrinsic to the growth plate cartilage.

• Klíčová slova
• Achondroplasia, Chondrocytes, FGF signaling, Statins,
• MeSH
• buněčná diferenciace účinky léků   MeSH
• buněčné linie MeSH
• chondrocyty účinky léků   metabolismus   MeSH
• chondrogeneze účinky léků   MeSH
• končetinové pupeny účinky léků   metabolismus   MeSH
• krysa rodu Rattus MeSH
• kultivované buňky MeSH
• lidé MeSH
• myši MeSH
• receptor fibroblastových růstových faktorů, typ 3 antagonisté a inhibitory   metabolismus   MeSH
• signální transdukce účinky léků   MeSH
• statiny farmakologie   MeSH
• techniky tkáňových kultur MeSH
• tibie účinky léků   embryologie   růst a vývoj   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• receptor fibroblastových růstových faktorů, typ 3 MeSH
• statiny MeSH

Fibroblast growth factor (FGF) signalling appears essential for the regulation of limb development, but a full complexity of this regulation remains unclear. Here, we addressed the effect of three different chemical inhibitors of FGF receptor tyrosine kinases (FGFR) on growth and patterning of the chicken wings. The inhibitor PD173074 caused shorter and thinner wing when using lower concentration. Microinjection of higher PD173074 concentrations (25 and 50 mmol/L) into the wing bud at stage 20 resulted in the development of small wing rudiment or the total absence of the wing. Skeletal analysis revealed the absence of the radius but not ulna, deformation of metacarpal bones and/or a reduction of digits. Treatment with PD161570 resembled the effects of PD173074. NF449 induced shortening and deformation of the developing wing with reduced autopodium. These malformed embryos mostly died at the stage HH25-29. PD173074 reduced chondrogenesis also in the limb micromass cultures together with early inhibition of cartilaginous nodule formation, evidenced by lack of sulphated proteoglycan and peanut agglutinin expression. The effect of FGFR inhibition on limb development observed here was unlikely mediated by excessive cell death as none of the inhibitors caused massive apoptosis at low concentrations. More probably, FGFR inhibition decreased both the proliferation and adhesion of mesenchymal chondroprogenitors. We conclude that FGFR signalling contributes to the regulation of the anterior-posterior patterning of zeugopod during chicken limb development.

• Klíčová slova
• chondrogenesis, fibroblast growth factor receptor, mesenchymal condensation, zeugopod,
• MeSH
• benzensulfonáty aplikace a dávkování   farmakologie   MeSH
• inhibitory proteinkinas aplikace a dávkování   farmakologie   MeSH
• křídla zvířecí účinky léků   embryologie   MeSH
• kuřecí embryo MeSH
• pyrimidiny aplikace a dávkování   farmakologie   MeSH
• receptory fibroblastových růstových faktorů antagonisté a inhibitory   metabolismus   MeSH
• signální transdukce účinky léků   MeSH
• zvířata MeSH
• Check Tag
• kuřecí embryo MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• 4,4,',4'',4'''-(carbonylbis(imino-5,1,3-benzenetriylbis(carbonylimino)))tetrakis(benzene-1,3-disulfonate) MeSH Prohlížeč
• benzensulfonáty MeSH
• inhibitory proteinkinas MeSH
• PD 173074 MeSH Prohlížeč
• pyrimidiny MeSH
• receptory fibroblastových růstových faktorů MeSH

A single primary cilium projects from most vertebrate cells to guide cell fate decisions. A growing list of signaling molecules is found to function through cilia and control ciliogenesis, including the fibroblast growth factor receptors (FGFR). Aberrant FGFR activity produces abnormal cilia with deregulated signaling, which contributes to pathogenesis of the FGFR-mediated genetic disorders. FGFR lesions are also found in cancer, raising a possibility of cilia involvement in the neoplastic transformation and tumor progression. Here, we focus on FGFR gene fusions, and discuss the possible mechanisms by which they function as oncogenic drivers. We show that a substantial portion of the FGFR fusion partners are proteins associated with the centrosome cycle, including organization of the mitotic spindle and ciliogenesis. The functions of centrosome proteins are often lost with the gene fusion, leading to haploinsufficiency that induces cilia loss and deregulated cell division. We speculate that this complements the ectopic FGFR activity and drives the FGFR fusion cancers.

• Klíčová slova
• FGFR, FGFR fusion, cancer, centrosome, centrosome cycle, cilia, fibroblast growth factor receptor, neoplastic transformation, oncogenic driver, primary cilia,
• MeSH
• centrozom metabolismus   MeSH
• cilie * metabolismus   patologie   MeSH
• lidé MeSH
• nádorová transformace buněk patologie   MeSH
• nádory * metabolismus   patologie   MeSH
• onkogenní fúze MeSH
• receptory fibroblastových růstových faktorů metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• receptory fibroblastových růstových faktorů MeSH

Activating mutations in the fibroblast growth factor receptor 3 (FGFR3) cause the most common genetic form of human dwarfism, achondroplasia (ACH). Small chemical inhibitors of FGFR tyrosine kinase activity are considered to be viable option for treating ACH, but little experimental evidence supports this claim. We evaluated five FGFR tyrosine kinase inhibitors (TKIs) (SU5402, PD173074, AZD1480, AZD4547 and BGJ398) for their activity against FGFR signaling in chondrocytes. All five TKIs strongly inhibited FGFR activation in cultured chondrocytes and limb rudiment cultures, completely relieving FGFR-mediated inhibition of chondrocyte proliferation and maturation. In contrast, TKI treatment of newborn mice did not improve skeletal growth and had lethal toxic effects on the liver, lungs and kidneys. In cell-free kinase assays as well as in vitro and in vivo cell assays, none of the tested TKIs demonstrated selectivity for FGFR3 over three other FGFR tyrosine kinases. In addition, the TKIs exhibited significant off-target activity when screened against a panel of 14 unrelated tyrosine kinases. This was most extensive in SU5402 and AZD1480, which inhibited DDR2, IGF1R, FLT3, TRKA, FLT4, ABL and JAK3 with efficiencies similar to or greater than those for FGFR. Low target specificity and toxicity of FGFR TKIs thus compromise their use for treatment of ACH. Conceptually, different avenues of therapeutic FGFR3 targeting should be investigated.

• MeSH
• achondroplazie farmakoterapie   MeSH
• benzamidy farmakologie   MeSH
• chondrocyty metabolismus   MeSH
• chrupavka účinky léků   metabolismus   MeSH
• fenylmočovinové sloučeniny farmakologie   MeSH
• katalýza účinky léků   MeSH
• kultivované buňky MeSH
• kuřecí embryo MeSH
• lidé MeSH
• myši MeSH
• piperaziny farmakologie   MeSH
• pyrazoly farmakologie   MeSH
• pyrimidiny farmakologie   MeSH
• pyrroly farmakologie   MeSH
• receptory fibroblastových růstových faktorů antagonisté a inhibitory   MeSH
• signální transdukce účinky léků   MeSH
• syndrom MeSH
• tyrosinkinasové receptory antagonisté a inhibitory   MeSH
• zvířata MeSH
• Check Tag
• kuřecí embryo MeSH
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• AZD 1480 MeSH Prohlížeč
• AZD4547 MeSH Prohlížeč
• benzamidy MeSH
• fenylmočovinové sloučeniny MeSH
• infigratinib MeSH Prohlížeč
• PD 173074 MeSH Prohlížeč
• piperaziny MeSH
• pyrazoly MeSH
• pyrimidiny MeSH
• pyrroly MeSH
• receptory fibroblastových růstových faktorů MeSH
• SU 5402 MeSH Prohlížeč
• tyrosinkinasové receptory MeSH

The onset of routine use of the next generation sequencing (NGS) leads to discovery of new mutations in non-small cell lung cancer (NSCLC). In addition, comprehension of therapeutic potential of these genetic alterations in clinical practice is needed and required. Both, rare mutations and the therapeutic considerations they prompt, are dealt with in our case report describing a new fusion mutation of the fibroblast growth factor receptor (FGFR). Our case report describes a 45-year Caucasian female, non-smoker, with the tyrosine-protein kinase Met (cMET) skip 14 mutation and a newly described fibroblast growth factor receptor-cholinergic receptor, nicotinic, alpha 6 (FGFR-CHNRA6) fusion. The tumor in this patient showed aggressive growth and was resistant to all treatment modalities administered (including combination chemotherapy with bevacizumab, pemetrexed and nintedanib), with the exception of very short efficacy of crizotinib. The patient died 5 months after diagnosis. According to the published literature, a theoretical future solution could be to administer multidimensional targeted therapy simultaneously.

• Klíčová slova
• Fibroblast growth factor receptor (FGFR), cMET, case report, crizotinib, nintedanib,
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH

Fibroblast growth factor 2 (FGF2) plays important roles in tissue development and repair. Using heparan sulfates (HS)/heparin as a cofactor, FGF2 binds to FGF receptor (FGFR) and induces downstream signaling pathways, such as ERK pathway, that regulate cellular behavior. In most cell lines, FGF2 signaling displays biphasic dose-response profile, reaching maximal response to intermediate concentrations, but weak response to high levels of FGF2. Recent reports demonstrated that the biphasic cellular response results from competition between binding of FGF2 to HS and FGFR that impinge upon ERK signaling dynamics. However, the role of HS/heparin in FGF signaling has been controversial. Several studies suggested that heparin is not required for FGF-FGFR complex formation and that the main role of heparin is to protect FGF from degradation. In this study, we investigated the relationship between FGF2 stability, heparin dependence and ERK signaling dynamics using FGF2 variants with increased thermal stability (FGF2-STABs). FGF2-STABs showed higher efficiency in induction of FGFR-mediated proliferation, lower affinity to heparin and were less dependent on heparin than wild-type FGF2 (FGF2-wt) for induction of FGFR-mediated mitogenic response. Interestingly, in primary mammary fibroblasts, FGF2-wt displayed a sigmoidal dose-response profile, while FGF2-STABs showed a biphasic response. Moreover, at low concentrations, FGF2-STABs induced ERK signaling more potently and displayed a faster dynamics of full ERK activation and higher amplitudes of ERK signaling than FGF2-wt. Our results suggest that FGF2 stability and heparin dependence are important factors in FGF-FGFR signaling complex assembly and ERK signaling dynamics.

• Klíčová slova
• extracellular-signal-regulated kinase (ERK), fibroblast growth factor, fibroblast growth factor receptor, fibroblasts, heparin, primary fibroblasts, signaling,
• Publikační typ
• časopisecké články MeSH

Tyrosine kinase inhibitors are being developed for therapy of malignancies caused by oncogenic FGFR signaling but little is known about their effect in congenital chondrodysplasias or craniosynostoses that associate with activating FGFR mutations. Here, we investigated the effects of novel FGFR inhibitor, ARQ 087, in experimental models of aberrant FGFR3 signaling in cartilage. In cultured chondrocytes, ARQ 087 efficiently rescued all major effects of pathological FGFR3 activation, i.e. inhibition of chondrocyte proliferation, loss of extracellular matrix and induction of premature senescence. In ex vivo tibia organ cultures, ARQ 087 restored normal growth plate architecture and eliminated the suppressing FGFR3 effect on chondrocyte hypertrophic differentiation, suggesting that it targets the FGFR3 pathway specifically, i.e. without interference with other pro-growth pathways. Moreover, ARQ 087 inhibited activity of FGFR1 and FGFR2 mutants associated with Pfeiffer, Apert and Beare-Stevenson craniosynostoses, and rescued FGFR-driven excessive osteogenic differentiation in mouse mesenchymal micromass cultures or in ex vivo calvarial organ cultures. Our data warrant further development of ARQ 087 for clinical use in skeletal disorders caused by activating FGFR mutations.

• Klíčová slova
• ARQ 087, Achondroplasia, Craniosynostosis, FGFR, Fibroblast growth factor receptor, Inhibitor, Skeletal dysplasia,
• MeSH
• aniliny farmakologie   terapeutické užití   MeSH
• bezbuněčný systém MeSH
• buněčná diferenciace * účinky léků   MeSH
• buněčné kultury MeSH
• chinazoliny farmakologie   terapeutické užití   MeSH
• chondrocyty účinky léků   metabolismus   patologie   MeSH
• extracelulární matrix účinky léků   metabolismus   MeSH
• fibroblastový růstový faktor 2 farmakologie   MeSH
• končetinové pupeny patologie   MeSH
• kraniosynostózy farmakoterapie   genetika   patologie   MeSH
• krysa rodu Rattus MeSH
• kur domácí MeSH
• lebka patologie   MeSH
• mutace genetika   MeSH
• myši MeSH
• orgánové kultury - kultivační techniky MeSH
• proliferace buněk účinky léků   MeSH
• receptory fibroblastových růstových faktorů genetika   MeSH
• signální transdukce * MeSH
• stárnutí buněk účinky léků   MeSH
• tibie účinky léků   patologie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• aniliny MeSH
• chinazoliny MeSH
• derazantinib MeSH Prohlížeč
• fibroblastový růstový faktor 2 MeSH
• receptory fibroblastových růstových faktorů MeSH

Sustained activation of extracellular signal-regulated kinase (ERK) drives pathologies caused by mutations in fibroblast growth factor receptors (FGFRs). We previously identified the inositol phosphatase SHIP2 (also known as INPPL1) as an FGFR-interacting protein and a target of the tyrosine kinase activities of FGFR1, FGFR3, and FGFR4. We report that loss of SHIP2 converted FGF-mediated sustained ERK activation into a transient signal and rescued cell phenotypes triggered by pathologic FGFR-ERK signaling. Mutant forms of SHIP2 lacking phosphoinositide phosphatase activity still associated with FGFRs and did not prevent FGF-induced sustained ERK activation, demonstrating that the adaptor rather than the catalytic activity of SHIP2 was required. SHIP2 recruited Src family kinases to the FGFRs, which promoted FGFR-mediated phosphorylation and assembly of protein complexes that relayed signaling to ERK. SHIP2 interacted with FGFRs, was phosphorylated by active FGFRs, and promoted FGFR-ERK signaling at the level of phosphorylation of the adaptor FRS2 and recruitment of the tyrosine phosphatase PTPN11. Thus, SHIP2 is an essential component of canonical FGF-FGFR signal transduction and a potential therapeutic target in FGFR-related disorders.

• MeSH
• adaptorové proteiny signální transdukční genetika   metabolismus   MeSH
• aktivace enzymů MeSH
• extracelulárním signálem regulované MAP kinasy genetika   metabolismus   MeSH
• fosfatidylinositol-3,4,5-trisfosfát-5-fosfatasy genetika   metabolismus   MeSH
• fosforylace MeSH
• HEK293 buňky MeSH
• lidé MeSH
• MAP kinasový signální systém * MeSH
• membránové proteiny genetika   metabolismus   MeSH
• nádorové buněčné linie MeSH
• receptory fibroblastových růstových faktorů genetika   metabolismus   MeSH
• skupina kinas odvozených od src-genu genetika   metabolismus   MeSH
• tyrosinfosfatasa nereceptorového typu 11 genetika   metabolismus   MeSH
• vazba proteinů MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• adaptorové proteiny signální transdukční MeSH
• extracelulárním signálem regulované MAP kinasy MeSH
• fosfatidylinositol-3,4,5-trisfosfát-5-fosfatasy MeSH
• FRS2 protein, human MeSH Prohlížeč
• INPPL1 protein, human MeSH Prohlížeč
• membránové proteiny MeSH
• PTPN11 protein, human MeSH Prohlížeč
• receptory fibroblastových růstových faktorů MeSH
• skupina kinas odvozených od src-genu MeSH
• tyrosinfosfatasa nereceptorového typu 11 MeSH