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1.
Acta Neuropathol Commun ; 10(1): 65, 2022 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-35484633

RESUMO

Glioblastoma (GBM) is characterized by a particularly invasive phenotype, supported by oncogenic signals from the fibroblast growth factor (FGF)/ FGF receptor (FGFR) network. However, a possible role of FGFR4 remained elusive so far. Several transcriptomic glioma datasets were analyzed. An extended panel of primary surgical specimen-derived and immortalized GBM (stem)cell models and original tumor tissues were screened for FGFR4 expression. GBM models engineered for wild-type and dominant-negative FGFR4 overexpression were investigated regarding aggressiveness and xenograft formation. Gene set enrichment analyses of FGFR4-modulated GBM models were compared to patient-derived datasets. Despite widely absent in adult brain, FGFR4 mRNA was distinctly expressed in embryonic neural stem cells and significantly upregulated in glioblastoma. Pronounced FGFR4 overexpression defined a distinct GBM patient subgroup with dismal prognosis. Expression levels of FGFR4 and its specific ligands FGF19/FGF23 correlated both in vitro and in vivo and were progressively upregulated in the vast majority of recurrent tumors. Based on overexpression/blockade experiments in respective GBM models, a central pro-oncogenic function of FGFR4 concerning viability, adhesion, migration, and clonogenicity was identified. Expression of dominant-negative FGFR4 resulted in diminished (subcutaneous) or blocked (orthotopic) GBM xenograft formation in the mouse and reduced invasiveness in zebrafish xenotransplantation models. In vitro and in vivo data consistently revealed distinct FGFR4 and integrin/extracellular matrix interactions. Accordingly, FGFR4 blockade profoundly sensitized FGFR4-overexpressing GBM models towards integrin/focal adhesion kinase inhibitors. Collectively, FGFR4 overexpression contributes to the malignant phenotype of a highly aggressive GBM subgroup and is associated with integrin-related therapeutic vulnerabilities.


Assuntos
Glioblastoma , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos , Animais , Carcinogênese , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Integrinas , Camundongos , Recidiva Local de Neoplasia , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/metabolismo , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra
2.
Molecules ; 25(19)2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-32998226

RESUMO

The tree fern Metaxya rostrata (Kunth) C. Presl is common in the rainforests of Central and South America, where suspensions of the dried rhizome are traditionally used to treat intestinal diseases. Two compounds from this plant, 2-deprenyl-rheediaxanthone B (XB) and 2-deprenyl-7-hydroxy-rheediaxanthone B (OH-XB), have been shown to be biologically highly active against colorectal cancer (CRC) cells in previous studies. The current investigation resulted in the isolation of the previously undescribed methylated xanthones 2-deprenyl-6-O-methyl-7-hydroxy-rheediaxanthone B, 2-deprenyl-5-O-methyl-7-methoxy-rheediaxanthone B, 2-deprenyl-5-O-methyl- 7-hydroxy-rheediaxanthone B and 2-deprenyl-7-methoxy-rheediaxanthone B. All compounds were isolated by column chromatography, structures were elucidated by one- and two-dimensional NMR-experiments and the identities of the compounds were confirmed by LC-HRMS. In logarithmically growing SW480 CRC cell cultures, cytotoxicity by neutral red uptake and MTT assays as well as caspase activation was analyzed. Cellular targets were examined by Western blot, and topoisomerase I (topo I) inhibition potential was tested. Comparing the structure-activity relationship with XB and OH-XB, the monomethylated derivatives showed qualitatively similar effects/mechanisms to their nonmethylated analogues, while dimethylation almost abolished the activity. Inhibition of topo I was dependent on the presence of an unmethylated 7-OH group.


Assuntos
Neoplasias Colorretais/patologia , Gleiquênias/química , Raízes de Plantas/química , Xantonas/farmacologia , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Caspases/metabolismo , Proteínas de Ciclo Celular/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , DNA Topoisomerases Tipo I/metabolismo , Humanos , Metilação , Espectroscopia de Prótons por Ressonância Magnética , Inibidores da Topoisomerase/farmacologia , Xantonas/química
3.
Liver Int ; 40(9): 2279-2290, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32378800

RESUMO

BACKGROUND & AIMS: Recently, overexpression of the fibroblast growth factor receptor 3 (FGFR3) splice variants FGFR3-IIIb and FGFR3-IIIc was found in ~50% of hepatocellular carcinoma (HCC). Here, we aim to identify FGFR3-IIIb/IIIc ligands, which drive the progression of HCC. METHODS: FACS, MTT assay and/or growth curves served to identify the FGFR3-IIIb/IIIc ligand being most effective to induce growth of hepatoma/hepatocarcinoma cell lines, established from human HCC. The most potent FGF was characterized regarding the expression levels in epithelial and stromal cells of liver and HCC and impact on neoangiogenesis, clonogenicity and invasive growth of hepatoma/hepatocarcinoma cells. RESULTS: Among all FGFR3-IIIb/IIIc ligands tested, FGF9 was the most potent growth factor for hepatoma/hepatocarcinoma cells. Replication and/or sprouting of blood/lymphendothelial cells was stimulated as well. FGF9 occurred mainly in stromal cells of unaltered liver but in epithelial cells of HCC. Every fifth HCC exhibited overexpressed FGF9 and frequent co-upregulation of FGFR3-IIIb/IIIc. In hepatoma/hepatocarcinoma cells FGF9 enhanced the capability for clonogenicity and disintegration of the blood and lymphatic endothelium, being most pronounced in cells overexpressing FGFR3-IIIb or FGFR3-IIIc, respectively. Any of the FGF9 effects in hepatoma/hepatocarcinoma cells was blocked completely by applying the FGFR1-3-specific tyrosine kinase inhibitor BGJ398 or siFGFR3, while siFGFR1/2/4 were mostly ineffective. CONCLUSIONS: FGF9 acts via FGFR3-IIIb/IIIc to enhance growth and aggressiveness of HCC cells. Accordingly, blockade of the FGF9-FGFR3-IIIb/IIIc axis may be an efficient therapeutic option for HCC patients.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Células Epiteliais , Fator 9 de Crescimento de Fibroblastos , Humanos , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética , Regulação para Cima
4.
Bioorg Med Chem ; 28(9): 115443, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32201190

RESUMO

A series of new Luotonin A derivatives with substituents at rings A and E was synthesized, together with some E-ring-unsubstituted derivatives. Subsequently, the compound library was examined in silico for their binding into a previously proposed site in the DNA/topoisomerase I binary complex. Whereas no convincing correlation between docking scores and biological data from in vitro assays could be found, one novel 4,9-diamino Luotonin A derivative had strong antiproliferative activity based on massive G2/M phase arrest. As this biological activity clearly differs from the reference compound Camptothecin, this strongly indicates that at least some Luotonin A derivatives may be potent antiproliferative agents, however with a different mode of action.


Assuntos
Antineoplásicos/farmacologia , Simulação de Acoplamento Molecular , Pirróis/farmacologia , Quinonas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Pirróis/síntese química , Pirróis/química , Quinonas/síntese química , Quinonas/química , Estereoisomerismo , Relação Estrutura-Atividade , Células Tumorais Cultivadas
5.
Planta Med ; 86(15): 1073-1079, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32023632

RESUMO

We recently isolated the prenylated xanthones 2-deprenyl-rheediaxanthone B (XB) and 2-deprenyl-7-hydroxy-rheediaxanthone B (OH-XB) from the South American tree fern Metaxya rostrata. This study explores the mechanisms underlying the FoxM1 downregulation induced by both xanthones. Analysis of cell viability and cell-death induction in SW480, HCT116, Caco-2, DLD1 and HT29 exposed to xanthones found cell-loss and activation of caspase in all cell lines except HT29 that do not have high FoxM1 protein levels. To determine the cellular mechanism of xanthone-induced FoxM1 loss, protein stability was analyzed by cycloheximide-chase experiments and showed reduction of FoxM1 stability by XB but not OH-XB. Destabilization was prevented by inhibiting proteasome activity using MG-132 and moderately by the lysosomal inhibitor bafilomycin A1 (baf A1). OH-XB had a stronger impact than XB on FoxM1 mRNA expression by qRT-PCR, and MG-132 positively affected FoxM1 protein level in OH-XB exposed cells even though no decrease in protein abundance had been induced by the xanthone. Additionally, the compound inhibited topoisomerase I causing DNA DSB and early cell cycle arrest. This may reduce FoxM1 gene expression, which may in turn compromise DNA repair and enhance xanthone-induced cell death. With regard to xanthone-induced cell death, MG-132 protected cultures from cell loss induced by both compounds, and baf A1 was active against these XB-induced effects. In summary, both destabilization of FoxM1 protein and topoisomerase I inhibition contribute to both XB and OH-XB cytotoxic activity albeit at different ratios.


Assuntos
DNA Topoisomerases Tipo I , Xantonas , Células CACO-2 , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Gleiquênias/química , Proteína Forkhead Box M1/genética , Humanos , Xantonas/toxicidade
6.
Cells ; 8(10)2019 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-31581712

RESUMO

Fibroblast growth factors (FGFs) are a large family of protein ligands that exert a wide range of biological effects in many organs/tissues by activating receptors (FGFRs) of the tyrosine kinase superfamily [...].


Assuntos
Terapia de Alvo Molecular , Neoplasias/tratamento farmacológico , Receptores de Fatores de Crescimento de Fibroblastos/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , Humanos , Pesquisa Translacional Biomédica
7.
Cancers (Basel) ; 11(10)2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31554208

RESUMO

Secreted protein acidic and rich in cysteine (SPARC) is a matricellular protein modulating cell-matrix interactions and was found up-regulated in tumor stroma. To explore the effect of high stromal SPARC on colorectal cancer (CRC) cell behavior and clinical outcome, this study determined SPARC expression in patients suffering from stage II and III CRC using a publicly available mRNA data set and immunohistochemistry of tissue microarray sections. Moreover, in vitro co-culture models using CRC cell lines together with colon-associated fibroblasts were established to determine the effect of fibroblast-derived SPARC on cancer cells. In 466 patient samples, high SPARC mRNA was associated with a shorter disease-free survival. In 99 patients of the tissue microarray cohort, high stromal SPARC in the primary tumor was an independent predictor of shorter survival in patients with relapse (27 cases; HR = 4574, p = 0.004). In CRC cell lines, SPARC suppressed phosphorylation of focal adhesion kinase and stimulated cell migration. Colon-associated fibroblasts increased migration velocity by 30% and doubled track-length in SPARC-dependent manner. In a 3D co-culture system, fibroblast-derived SPARC enhanced tumor cell invasion. Taken together, stromal SPARC had a pro-metastatic impact in vitro and was a characteristic of aggressive tumors with poor prognosis in CRC patients.

8.
Cells ; 8(9)2019 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-31527546

RESUMO

Even though distinctive advances in the field of esophageal cancer therapy have occurred over the last few years, patients' survival rates remain poor. FGF8, FGF18, and FGFR4 have been identified as promising biomarkers in a number of cancers; however no data exist on expression of FGF8, FGF18, and FGFR4 in adenocarcinomas of the esophago-gastric junction (AEG). A preliminary analysis of the Cancer Genome Atlas (TCGA) database on FGF8, FGF18, and FGFR4 mRNA expression data of patients with AEG was performed. Furthermore, protein levels of FGF8, FGF18, and FGFR4 in diagnostic biopsies and post-operative specimens in neoadjuvantly treated and primarily resected patients using immunohistochemistry were investigated. A total of 242 patients was analyzed in this study: 87 patients were investigated in the TCGA data set analysis and 155 patients in the analysis of protein expression using immunohistochemistry. High protein levels of FGF8, FGF18, and FGFR4 were detected in 94 (60.7%), 49 (31.6%) and 84 (54.2%) patients, respectively. Multivariable Cox proportional hazard regression models revealed that high expression of FGF8 was an independent prognostic factor for diminished overall survival for all patients and for neoadjuvantly treated patients. By contrast, FGF18 overexpression was significantly associated with longer survival rates in neoadjuvantly treated patients. In addition, FGF8 protein level correlated with Mandard regression due to neoadjuvant therapy, indicating potential as a predictive marker. In summary, FGF8 and FGF18 are promising candidates for prognostic factors in adenocarcinomas of the esophago-gastric junction and new potential targets for new anti-cancer therapies.


Assuntos
Adenocarcinoma/metabolismo , Neoplasias Esofágicas/metabolismo , Fator 8 de Crescimento de Fibroblasto/biossíntese , Fatores de Crescimento de Fibroblastos/biossíntese , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/biossíntese , Adenocarcinoma/diagnóstico , Adenocarcinoma/patologia , Idoso , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/patologia , Feminino , Fator 8 de Crescimento de Fibroblasto/genética , Fatores de Crescimento de Fibroblastos/genética , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/genética , Taxa de Sobrevida
10.
Phytomedicine ; 60: 152912, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30979690

RESUMO

BACKGROUND: Metaxya rostrata C.Presl (Metaxyaceae) is a tree fern widespread in Central and South America and the dried rhizome is used in ethnic medicine against intestinal ulcers or tumors. An activity-guided isolation resulted in two structurally related xanthones: 2-deprenyl-rheediaxanthone B (XB) and 2-deprenyl-7-hydroxy-rheediaxanthone B (OH-XB). HYPOTHESIS/PURPOSE: This study analyzed the cytotoxic activity and underlying cellular mechanisms of OH-XB for the first time in comparison to XB. METHODS: We exposed the colorectal cancer cell line SW480 and F331 fibroblasts to XB and OH-XB and determined cell viability by neutral red uptake and nuclear morphology by staining with Hoechst dye. Cell cycle distribution and the mechanism of cell death were analyzed by FACS and western blot. Knockdown of FoxM1 expression was performed with siRNA. RESULTS: OH-XB was at least as cytotoxic as XB in the induction of cell cycle arrest and active cell death. While both compounds strongly inhibited the transcription factor FoxM1, the cellular mechanisms of growth arrest and cell death induction differed widely: OH-XB induced S-phase cell cycle arrest in contrast to a G2-M-phase arrest by XB. It caused morphological modifications typical for classical apoptosis with increased caspase 7 activity and enhanced cleavage of PARP, while XB caused caspase 2 activation and mitotic catastrophe. After knockdown of FoxM1 expression no induction of caspase activity could be observed. CONCLUSION: In summary, our data clearly showed that XB and OH-XB are promising new lead compounds for cancer therapy with distinct cellular mechanisms. Both compounds are candidates for further pre-clinical and clinical investigations.


Assuntos
Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Gleiquênias/química , Proteína Forkhead Box M1/efeitos dos fármacos , Xantonas/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Proteína Forkhead Box M1/metabolismo , Fase G2/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Mitose/efeitos dos fármacos , Prenilação , Rizoma/química , Xantonas/química
11.
Molecules ; 24(4)2019 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-30781470

RESUMO

Following two orthogonal synthetic routes, a series of all four possible A-ring amino derivatives of the natural product Luotonin A (a known Topoisomerase I inhibitor) was synthesized. In both strategies, intramolecular cycloaddition reactions are the key step. The target compounds were obtained in good yields by mild catalytic transfer hydrogenation of the corresponding nitro precursors. In-vitro evaluation of the antiproliferative activity towards human tumor cell lines revealed the 4-amino compound (5b) to be the most effective agent, showing an interesting profile of cytotoxic activity. Among other effects, a significant G2/M cell cycle arrest was observed for this compound, suggesting that either Topoisomerase I is not the only biological target, or that some atypical mechanism is responsible for inhibition of this enzyme.


Assuntos
Alcaloides/síntese química , Alcaloides/farmacologia , Pirróis/síntese química , Pirróis/farmacologia , Quinonas/síntese química , Quinonas/farmacologia , Alcaloides/química , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Química Sintética , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Pirróis/química , Quinonas/química , Espectrometria de Massas por Ionização por Electrospray , Relação Estrutura-Atividade , Inibidores da Topoisomerase I/síntese química , Inibidores da Topoisomerase I/química , Inibidores da Topoisomerase I/farmacologia
12.
J Cancer Res Clin Oncol ; 145(1): 77-86, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30276721

RESUMO

PURPOSE: Therapy response to neoadjuvant radiochemotherapy (nRCT) of locally advanced rectal cancer varies widely so that markers predicting response are urgently needed. Fibroblast growth factor (FGF) and FGF receptor (FGFR) signaling is involved in pro-survival signaling and thereby may result in radiation resistance. METHODS: In a cohort of 43 rectal cancer patients, who received nRCT, we analyzed protein levels of FGF 8 and its downstream target Survivin by immunohistochemistry to assess their impact on nRCT response. In vitro resistance models were created by exposing colorectal cancer cell lines to fractionated irradiation and selecting long-term survivors. RESULTS: Our findings revealed significantly higher FGF8 and Survivin staining scores in pre-treatment biopsies as well as in surgical specimens of non-responsive compared to responsive patients. Functional studies demonstrated dose-dependent induction of FGF8 mRNA expression in mismatch-incompetent DLD1 cells already after one dose of irradiation. Surviving clones after one or two series of radiation were more resistant to an additional radiation fraction than non-irradiated controls and showed a significant increase in expression of the FGF8 receptor FGFR3 and of Survivin on both the RNA and the protein levels. CONCLUSION: The results of this study suggest that FGF8 and Survivin contribute to radiation resistance in rectal cancer and may serve as markers to select patients who may not benefit from neoadjuvant radiotherapy.


Assuntos
Quimiorradioterapia Adjuvante , Fator 8 de Crescimento de Fibroblasto/fisiologia , Tolerância a Radiação/fisiologia , Neoplasias Retais/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose/efeitos da radiação , Linhagem Celular Tumoral , Sobrevivência Celular/fisiologia , Quimiorradioterapia , Resistencia a Medicamentos Antineoplásicos , Feminino , Fator 8 de Crescimento de Fibroblasto/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/metabolismo , Neoplasias Retais/patologia , Neoplasias Retais/cirurgia , Estudos Retrospectivos , Transdução de Sinais/fisiologia , Survivina/metabolismo
13.
Wien Klin Wochenschr ; 130(17-18): 517-529, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30006759

RESUMO

In 2008 the Ludwig Boltzmann Cluster Oncology (LBC ONC) was established on the basis of two previous Ludwig Boltzmann Institutes working in the field of hematology and cancer research. The general aim of the LBC ONC is to improve treatment of hematopoietic neoplasms by eradicating cancer-initiating and disease-propagating cells, also known as leukemic stem cells (LSC) in the context of leukemia. In a first phase, the LBC ONC characterized the phenotype and molecular aberration profiles of LSC in various malignancies. The LSC phenotypes were established in acute and chronic myeloid leukemia, in acute lymphoblastic leukemia and in chronic lymphocytic leukemia. In addition, the concept of preleukemic (premalignant) neoplastic stem cells (pre-L-NSC) was coined by the LBC ONC and was tested in myelodysplastic syndromes and myeloproliferative neoplasms. Phenotypic characterization of LSC provided a solid basis for their purification and for the characterization of specific target expression profiles. In a second phase, molecular markers and targets were validated. This second phase is ongoing and should result in the development of new diagnostics parameters and novel, more effective, LSC-eradicating, treatment strategies; however, many issues still remain to be solved, such as sub-clonal evolution, LSC niche interactions, immunologic control of LSC, and LSC resistance. In the forthcoming years, the LBC ONC will concentrate on developing LSC-eradicating strategies, with special focus on LSC resistance, precision medicine and translation of LSC-eradicating concepts into clinical application.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , Humanos , Células-Tronco Neoplásicas
14.
Carcinogenesis ; 39(4): 534-545, 2018 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-29635378

RESUMO

Malignant pleural mesothelioma (MPM), an aggressive malignancy affecting pleural surfaces, occurs in three main histological subtypes. The epithelioid and sarcomatoid subtypes are characterized by cuboid and fibroblastoid cells, respectively. The biphasic subtype contains a mixture of both. The sarcomatoid subtype expresses markers of epithelial-mesenchymal transition (EMT) and confers the worst prognosis, but the signals and pathways controlling EMT in MPM are not well understood. We demonstrate that treatment with FGF2 or EGF induced a fibroblastoid morphology in several cell lines from biphasic MPM, accompanied by scattering, decreased cell adhesion and increased invasiveness. This depended on the MAP-kinase pathway but was independent of TGFß or PI3-kinase signaling. In addition to changes in known EMT markers, microarray analysis demonstrated differential expression of MMP1, ESM1, ETV4, PDL1 and BDKR2B in response to both growth factors and in epithelioid versus sarcomatoid MPM. Inhibition of MMP1 prevented FGF2-induced scattering and invasiveness. Moreover, in MPM cells with sarcomatoid morphology, inhibition of FGF/MAP-kinase signaling induced a more epithelioid morphology and gene expression pattern. Our findings suggest a critical role of the MAP-kinase axis in the morphological and behavioral plasticity of mesothelioma.


Assuntos
Fator de Crescimento Epidérmico/metabolismo , Transição Epitelial-Mesenquimal/fisiologia , Fator 2 de Crescimento de Fibroblastos/metabolismo , Neoplasias Pulmonares/patologia , Mesotelioma/patologia , Neoplasias Pleurais/patologia , Linhagem Celular Tumoral , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Neoplasias Pulmonares/metabolismo , Metaloproteinase 1 da Matriz/metabolismo , Mesotelioma/metabolismo , Mesotelioma Maligno , Neoplasias Pleurais/metabolismo , Transdução de Sinais/fisiologia
15.
Clin Proteomics ; 14: 33, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29176937

RESUMO

BACKGROUND: Cancer associated fibroblasts are activated in the tumor microenvironment and contribute to tumor progression, angiogenesis, extracellular matrix remodeling, and inflammation. METHODS: To identify proteins characteristic for fibroblasts in colorectal cancer we used liquid chromatography-tandem mass spectrometry to derive protein abundance from whole-tissue homogenates of human colorectal cancer/normal mucosa pairs. Alterations of protein levels were determined by two-sided t test with greater than threefold difference and an FDR of < 0.05. Public available datasets were used to predict proteins of stromal origin and link protein with mRNA regulation. Immunohistochemistry confirmed the localization of selected proteins. RESULTS: We identified a set of 24 proteins associated with inflammation, matrix organization, TGFß receptor signaling and angiogenesis mainly originating from the stroma. Most prominent were increased abundance of SerpinB5 in the parenchyme and latent transforming growth factor ß-binding protein, thrombospondin-B2, and secreted protein acidic-and-cysteine-rich in the stroma. Extracellular matrix remodeling involved collagens type VIII, XII, XIV, and VI as well as lysyl-oxidase-2. In silico analysis of mRNA levels demonstrated altered expression in the tumor and the adjacent normal tissue as compared to mucosa of healthy individuals indicating that inflammatory activation affected the surrounding tissue. Immunohistochemistry of 26 tumor specimen confirmed upregulation of SerpinB5, thrombospondin B2 and secreted protein acidic-and-cysteine-rich. CONCLUSIONS: This study demonstrates the feasibility of detecting tumor- and compartment-specific protein-signatures that are functionally meaningful by proteomic profiling of whole-tissue extracts together with mining of RNA expression datasets. The results provide the basis for further exploration of inflammation-related stromal markers in larger patient cohorts and experimental models.

16.
Oncotarget ; 8(50): 87750-87762, 2017 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-29152117

RESUMO

Although FGF5 mRNA was previously found expressed in some melanoma cell lines in contrast to normal human melanocytes, neither its contribution to melanoma growth nor its expression in melanoma tissue has been investigated. Here we demonstrate that ectopic overexpression of FGF5 in human melanoma cells with low endogenous FGF5 expression increased clonogenicity and invasion but not short-term growth in vitro. Silencing of FGF5 in melanoma cells with high endogenous FGF5 expression had the opposite effect on clonogenicity. FGF overexpression led to increased signaling along the MAPK and NFAT axis but had no effect on STAT3 signaling. In an in vivo experiment in immunocompromised mice, human melanoma xenografts overexpressing FGF5 showed enhanced tumor growth, a higher Ki-67 proliferation index, decreased apoptosis and enhanced angiogenesis. Immunohistochemistry performed on a tissue microarray demonstrated FGF5 protein expression in more than 50% of samples of melanoma and benign nevi. These data suggest that FGF5 has oncogenic potential in melanoma cells and contributes to melanoma growth in a subset of patients. This highlights the importance of further evaluating FGF5 as potential biomarker and therapy target in melanoma.

17.
Molecules ; 22(9)2017 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-28895937

RESUMO

An oxidative ring opening reaction of the central ring C in the alkaloid Luotonin A and two of its derivatives was found to occur upon heating with an excess amine and potassium carbonate in dimethylsulfoxide (DMSO) solution in the presence of air oxygen. The structure of the novel amide-type products was elucidated and a possible mechanism for this reaction is proposed. Four of the new compounds show moderate in vitro anticancer activity towards human colon adenocarcinoma cells.


Assuntos
Oxirredução , Pirróis/química , Quinonas/química , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Pirróis/síntese química , Pirróis/farmacologia , Quinonas/síntese química , Quinonas/farmacologia
18.
Transl Oncol ; 10(3): 332-339, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28340475

RESUMO

BACKGROUND: Irinotecan (IRI) is an integral part of colorectal cancer (CRC) therapy, but response rates are unsatisfactory and resistance mechanisms are still insufficiently understood. As fibroblast growth factor receptor 3 (FGFR3) mediates essential survival signals in CRC, it is a candidate gene for causing intrinsic resistance to IRI. METHODS: We have used cell line models overexpressing FGFR3 to study the receptor's impact on IRI response. For pathway blockade, a dominant-negative receptor mutant and a small molecule kinase inhibitor were employed. RESULTS: IRI exposure induced expression of FGFR3 as well as its ligands FGF8 and FGF18 both in cell cultures and in xenograft tumors. As overexpression of FGFR3 mitigated IRI-induced apoptosis in CRC cell models, this suggests that the drug itself activated a survival response. On the cellular level, the antiapoptotic protein bcl-xl was upregulated and caspase 3 activation was inhibited. Targeting FGFR3 signaling using a dominant-negative receptor mutant sensitized cells for IRI. In addition, the FGFR inhibitor PD173074 acted synergistically with the chemotherapeutic drug and significantly enhanced IRI-induced caspase 3 activity in vitro. In vivo, PD173074 strongly inhibited growth of IRI-treated tumors. CONCLUSION: Together, our results indicate that targeting FGFR3 can be a promising strategy to enhance IRI response in CRC patients.

19.
Cell Mol Life Sci ; 74(10): 1907-1921, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28013338

RESUMO

Retraction of mesenchymal stromal cells supports the invasion of colorectal cancer cells (CRC) into the adjacent compartment. CRC-secreted 12(S)-HETE enhances the retraction of cancer-associated fibroblasts (CAFs) and therefore, 12(S)-HETE may enforce invasivity of CRC. Understanding the mechanisms of metastatic CRC is crucial for successful intervention. Therefore, we studied pro-invasive contributions of stromal cells in physiologically relevant three-dimensional in vitro assays consisting of CRC spheroids, CAFs, extracellular matrix and endothelial cells, as well as in reductionist models. In order to elucidate how CAFs support CRC invasion, tumour spheroid-induced CAF retraction and free intracellular Ca2+ levels were measured and pharmacological- or siRNA-based inhibition of selected signalling cascades was performed. CRC spheroids caused the retraction of CAFs, generating entry gates in the adjacent surrogate stroma. The responsible trigger factor 12(S)-HETE provoked a signal, which was transduced by PLC, IP3, free intracellular Ca2+, Ca2+-calmodulin-kinase-II, RHO/ROCK and MYLK which led to the activation of myosin light chain 2, and subsequent CAF mobility. RHO activity was observed downstream as well as upstream of Ca2+ release. Thus, Ca2+ signalling served as central signal amplifier. Treatment with the FDA-approved drugs carbamazepine, cinnarizine, nifedipine and bepridil HCl, which reportedly interfere with cellular calcium availability, inhibited CAF-retraction. The elucidation of signalling pathways and identification of approved inhibitory drugs warrant development of intervention strategies targeting tumour-stroma interaction.


Assuntos
Ácido 12-Hidroxi-5,8,10,14-Eicosatetraenoico/metabolismo , Fibroblastos Associados a Câncer/patologia , Colo/patologia , Neoplasias Colorretais/patologia , Reto/patologia , Transdução de Sinais , Cálcio/metabolismo , Fibroblastos Associados a Câncer/metabolismo , Miosinas Cardíacas/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Colo/metabolismo , Neoplasias Colorretais/metabolismo , Humanos , Cadeias Leves de Miosina/metabolismo , Invasividade Neoplásica/patologia , Reto/metabolismo , Quinases Associadas a rho/metabolismo
20.
Oncotarget ; 7(45): 73800-73816, 2016 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-27650542

RESUMO

ESRPs are master splice regulators implicated in alternative mRNA splicing programs important for epithelial-mesenchymal transition (EMT) and tumor progression. ESRP1 was identified in some tumors as good or worse predictor of outcome, but in colorectal cancer (CRC) the prognostic value of ESRPs and relation with mesenchymal splice variants is not clear. Here, we studied 68 CRC cases, compared tissue expression of ESRPs with clinical data and with EMT gene splice patterns of conditional CRC cells with deficient ESRP1 expression.Around 72% of patients showed global decreased transcript expression of both ESRPs in tumor as compared to matched non-neoplastic colorectal epithelium. Reduction of ESRP1 in tumor cells was evaluated by immunohistochemistry, associated with microsatellite stability and switch to mesenchymal splice signatures of FGFRs, CD44, ENAH and CTNND1(p120-catenin). Expression of ESRPs was significantly associated with favorable overall survival (log-rank test, P=0.0186 and 0.0408), better than prognostic stratification by tumor staging; and for ESRP1 confirmed with second TCGA cohort (log-rank test, P=0.0435). Prognostic value is independent of the pathological stage and microsatellite instability (ESRP1: HR=0.36, 95%CI 0.15-0.91, P=0.032; ESRP2: HR=0.23, 95%CI 0.08-0.65, P=0.006).Our study supports the role of ESRP1 as tumor suppressor and strongly suggests that ESRPs are candidate markers for early detection, diagnosis, and prognosis of CRC.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/mortalidade , Splicing de RNA , Proteínas de Ligação a RNA/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular Tumoral , Neoplasias Colorretais/diagnóstico , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Instabilidade de Microssatélites , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Proteínas de Ligação a RNA/metabolismo
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