Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Oncotarget ; 13: 1140-1152, 2022 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-36264073

RESUMO

Platelet-derived growth factor (PDGF) signaling, besides other growth factor-mediated signaling pathways like vascular endothelial growth factor (VEGF) and epidermal growth factor (EGF), seems to play a crucial role in tumor development and progression. We have recently provided evidence for upregulation of PDGF expression in UICC stage I-IV primary colorectal cancer (CRC) and demonstrated PDGF-mediated induction of PI3K/Akt/mTOR signaling in CRC cell lines. The present study sought to follow up on our previous findings and explore the alternative receptor cross-binding potential of PDGF in CRC. Our analysis of primary human colon tumor samples demonstrated upregulation of the PDGFRß, VEGFR1, and VEGFR2 genes in UICC stage I-III tumors. Immunohistological analysis revealed co-expression of PDGF and its putative cross-binding partners, VEGFR2 and EGFR. We then analyzed several CRC cell lines for PDGFRα, PDGFRß, VEGFR1, and VEGFR2 protein expression and found these receptors to be variably expressed amongst the investigated cell lines. Interestingly, whereas Caco-2 and SW480 cells showed expression of all analyzed receptors, HT29 cells expressed only VEGFR1 and VEGFR2. However, stimulation of HT29 cells with PDGF resulted in upregulation of VEGFR1 and VEGFR2 expression despite the absence of PDGFR expression and mimicked the effect of VEGF stimulation. Moreover, PDGF recovered HT29 cell proliferation under simultaneous treatment with a VEGFR or EGFR inhibitor. Our results provide some of the first evidence for PDGF cross-signaling through alternative receptors in colorectal cancer and support anti-PDGF therapy as a combination strategy alongside VEGF and EGF targeting even in tumors lacking PDGFR expression.


Assuntos
Neoplasias Colorretais , Fator de Crescimento Derivado de Plaquetas , Humanos , Fator de Crescimento Derivado de Plaquetas/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Crescimento Epidérmico , Fosfatidilinositol 3-Quinases , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Células CACO-2 , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Serina-Treonina Quinases TOR , Neoplasias Colorretais/patologia , Receptores ErbB , Receptores do Fator de Crescimento Derivado de Plaquetas
2.
Front Immunol ; 11: 684, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32425932

RESUMO

Background: Colorectal cancer (CRC) is frequently associated with dysbiosis of the gut microbiome which, together with a compromised gut barrier, can result in perioperative endotoxin leakage into the circulation. Constant local and systemic inflammatory activity is suggested to facilitate metastases formation. Previous studies have pointed to the capacity of a colostrum preparation to neutralize endotoxins within the gastrointestinal tract which could ameliorate associated inflammatory responses and tumor recurrence in affected patients. This study aimed to examine the effects of the colostrum preparation, KMP01D, on the inflammatory activity of patient-derived immune cells. Methods: The effects of KMP01D on pro-/anti-inflammatory cytokine responses and apoptosis were examined ex vivo using immune cells from CRC patients (stages I-IV, n = 48). The expression of CD14, CD68, Toll-like receptor (TLR)4, and insulin-like growth factor (IGF)-1 was also analyzed. Results: KMP01D increased interleukin (IL)-10 and IL-13 anti-inflammatory cytokine expression in patient-derived peripheral blood mononuclear cells (PBMCs). Interestingly, KMP01D also decreased the secretion of IL-1ß, IL-6, interferon (IFN)-γ, tumor necrosis factor (TNF)-α, IL-12 inflammatory cytokines, and IGF-1 in these cells. Moreover, CD14 and TLR4 expression involved in endotoxin signaling was downregulated in PBMCs and tumor-derived cells. Apoptosis of immune cells and tumor-derived cells was likewise enhanced with KMP01D. Addition of vitamin D3 as a cofactor demonstrated enhanced anti-inflammatory effects. Conclusions: KMP01D demonstrated beneficial ex vivo effects on inflammatory cytokine responses in PBMCs and enhanced apoptosis of immune cells from CRC patients. In line with previous clinical trials, we present new evidence endorsing KMP01D as a treatment strategy to regulate stage-dependent local and systemic inflammation in CRC patients.


Assuntos
Anti-Inflamatórios/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Colostro , Monócitos/efeitos dos fármacos , Idoso , Apoptose , Colecalciferol/farmacologia , Neoplasias Colorretais/imunologia , Citocinas/biossíntese , Microbioma Gastrointestinal/fisiologia , Humanos , Imunoglobulinas Intravenosas/farmacologia , Fator de Crescimento Insulin-Like I/fisiologia , Pessoa de Meia-Idade , Monócitos/imunologia , Estudos Prospectivos
3.
Int J Clin Pharmacol Ther ; 56(2): 53-55, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29319494

RESUMO

There is strong evidence that tumor progression in the postoperative period is attributable to the influx of lipopolysaccharides (LPS) into the blood from the gastrointestinal (GI) lumen. Although several research groups have emphasized the need to neutralize LPS antigens from the GI tract to prevent tumor progression and reduce the inflammatory response, a therapeutic option to achieve this has not been put forward hitherto. Enterally applied immunoglobulins (IgG) in the form of colostrum concentrates are able to neutralize LPS antigens from the GI tract and to reduce the inflammatory response during abdominal surgery. Thus, the perioperative oral application of IgG appears to be an interesting and safe therapeutic option during colon carcinoma resection. A treatment strategy suitable for routine use at low cost in such patients and based on polyvalent immunoglobulins containing IgG is described.
.


Assuntos
Colectomia/efeitos adversos , Neoplasias do Colo/terapia , Microbioma Gastrointestinal/imunologia , Imunoglobulinas/administração & dosagem , Inflamação/prevenção & controle , Administração Oral , Neoplasias do Colo/imunologia , Neoplasias do Colo/microbiologia , Neoplasias do Colo/patologia , Progressão da Doença , Esquema de Medicação , Humanos , Inflamação/imunologia , Inflamação/microbiologia , Lipopolissacarídeos/imunologia , Fatores de Proteção , Medição de Risco , Fatores de Risco , Resultado do Tratamento
4.
Int J Clin Pharmacol Ther ; 56(1): 24-27, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29231165

RESUMO

BACKGROUND: Sjogren's syndrome, involving sicca symptoms with xerostomia, stomatitis, and considerable pain is a difficult-to-treat autoimmune disease where the treatment options are limited and, as in the case of methotrexate, have a low therapeutic index. CASE REPORT: This case report concerns a male patient, aged 75 years and vegetarian, with Sjogren's syndrome subsequently confirmed by salivary gland biopsy. Serum antinuclear antibodies (ANA) were elevated (1 : 320). Low serum vitamin B12 and iron levels could be improved after 20 days using vitamin B12 and iron oral supplements. Despite symptomatic treatment, xerostomia, glossitis, and glossodynia were still present, at times marked, after 12 months when the ANA titer was unchanged. Following treatment with an anti-inflammatory polyvalent immunoglobulin formulation (Lactobin®N, 7 g daily), a bovine colostrum concentrate given orally in combination with oral vitamin D3 (2,000 IU daily), sicca symptoms and xerostomia progressively decreased and at day 750 were confined to occasional and minor glossitis of the upper lip. CONCLUSION: This case report demonstrates the satisfactory control of Sjogren's syndrome using oral polyvalent immunoglobulins with vitamin D3. In contrast to treatment options involving antimalarial drugs and methotrexate, there are no safety issues in patients tolerant to milk products.
.


Assuntos
Colecalciferol/administração & dosagem , Imunoglobulinas/uso terapêutico , Síndrome de Sjogren/tratamento farmacológico , Estomatite/tratamento farmacológico , Vitamina B 12/administração & dosagem , Idoso , Anticorpos Antinucleares/sangue , Humanos , Masculino , Síndrome de Sjogren/imunologia , Estomatite/imunologia , Vegetarianos
6.
Oncotarget ; 7(42): 68749-68767, 2016 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-27626684

RESUMO

Platelet-derived growth factor (PDGF) and signaling via its receptors plays a crucial role in tumor cell proliferation and thus may represent an attractive target besides VEGF/EGFR-based antibody therapies. In this study we analyzed the influence of PDGF in colorectal cancer. PDGF was expressed intensively in early and even more intensively in late stage primary CRCs. Like VEGF, PDGF enhanced human colon cancer proliferation, and increased oxidative glycolytic activity, and activated HIF1α and c-Myc in vitro. PDGF activated the PI3K/Akt/mTOR pathway while leaving MAPK signaling untouched. Further dissection showed that inhibition of Akt strongly impeded cancer cell growth while inhibition of PI3K did not. MAPK analysis suggested an inhibitory crosstalk between both pathways, thus explaining the different effects of the Akt and PI3K inhibitors on cancer cell proliferation. PDGF stimulates colon cancer cell proliferation, and prevents inhibitor induced apoptosis, resulting in tumor growth. Therefore inhibition of PDGF signaling seems to be a promising target in colorectal cancer therapy. However, due to the multifaceted nature of the intracellular PDGF signaling, careful intervention strategies are needed when looking into specific signaling pathways like PI3K/Akt/mTOR and MAPK.


Assuntos
Proliferação de Células/efeitos dos fármacos , Glicólise/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Fator de Crescimento Derivado de Plaquetas/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Células HCT116 , Células HT29 , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fator de Crescimento Derivado de Plaquetas/genética , Transdução de Sinais/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/farmacologia
7.
Ther Apher ; 6(2): 145-53, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11982956

RESUMO

In this study, we compared a standardized solution of human serum protein (HSP) and fresh frozen plasma (FFP) with regard to the antibody specificity against a number of microbial pathogens and some important pathogenicity factors of bacterial pathogens. Due to the clinical use of HSP and FFP for therapeutical plasma exchange, we have chosen a spectrum of microbial pathogens for serological analysis that is critical in clinical settings. With the enzyme-linked immunosorbent assay technique, we could show that HSP contains marked IgG antibody reactivity against antigens of Escherichia coli, Campylobacter jejuni, Enterobacter sakazakii, Proteus mirabilis, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus, S. epidermidis, Streptococcus pneumoniae, Enterococcus faecalis, Chlamydia pneumoniae, and Candida albicans. Although no IgM antibodies against the pathogens tested could be detected in HSP, moderate IgA reactivity was found against 4 of 12 microbial antigens. Immunoblot analysis demonstrated specific IgA and IgG responses against the endoproteinase Glu-C and the superantigens enterotoxin A and B of S. aureus, the IgA-protease of Neisseria gonorrhoeae, and Shiga toxin 2 of enterohemorrhagic E. coli. By using 3 different HSP batches in parallel, we could demonstrate antibody reactivity against important microbial pathogens and toxins. This antibody profile is essentially more homogeneous than that of 3 batches of FFP.


Assuntos
Proteínas Sanguíneas , Patógenos Transmitidos pelo Sangue , Plasma , Toxinas Biológicas/imunologia , Especificidade de Anticorpos , Antígenos de Bactérias/imunologia , Proteínas Fúngicas/imunologia , Humanos , Troca Plasmática , Soluções , Virulência
8.
J Food Prot ; 60(11): 1454-1457, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31207762

RESUMO

A prospective study was carried out in collaboration with two children's hospitals in Würzburg, Germany to assess the incidence and clinical manifestations of infections due to Shiga toxin-producing Escherichia coli (STEC) in children. Between 1991 and 1995, stool samples from 2788 children with enteritis were investigated for the occurrence of STEC. STEC cultures from stools were screened using PCR with primers complementary to Shiga toxin 1(Stx1) and Shiga toxin 2 (Stx2) genes. PCR-positive samples were further subjected to colony blot hybridization and probe positive colonies were serotyped and analyzed for the presence of virulence genes. There was an increase in the incidence of STEC infections from 0.4% in 1991 to 2.8% in 1994. In 1995 the number of infections remained nearly unchanged (2.5%). Infection with STEC was associated with painful nonbloody diarrhea in most patients. Among the 35 patients in this study with stools containing STEC, only 9 (25.7%) had O157 colonies of which 3 (8.6%) were O157:H7 and 6 (17.1%) were sorbitol-fermenting O157:H-. In an additional study in 1994/l995, STEC etiology in 88 patients with HUS from Germany was confirmed in our laboratories by culture of STEC from stools, and in 20 additional HUS cases by serological analysis. Of the strains from stools of HUS patients, 78% belonged to serogroup O157. The most frequently isolated non-O157 serogroups were O26 and O111. These results demonstrate that when analyzing stools of patients with bloody diarrhea, HUS, or painful nonbloody diarrhea, the occurrence of non-O157:H7 strains should be considered when classical microbiological analysis fails to yield a standard enteric pathogen, such as Campylobacter . E. coli O157:H7, Salmonella . Shigella , or Yersinia .

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA