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191.
192.
J Szkandera G Absenger B Liegl-Atzwanger M Pichler M Stotz H Samonigg M Glehr M Zacherl T Stojakovic A Gerger A Leithner 《British journal of cancer》2013,108(8):1677-1683
Background:
Recent data indicate that tumour microenvironment, which is influenced by inflammatory cells, has a crucial role in cancer progression and clinical outcome of patients. In the present study, we investigated the prognostic relevance of preoperative neutrophil/lymphocyte (N/L) ratio on time to tumour recurrence (TTR) and overall survival (OS) in soft-tissue sarcoma (STS) patients who underwent curative surgical resection.Methods:
In all, 260 STS patients were included in this retrospective study. Kaplan–Meier curves and multivariate Cox proportional models were calculated for TTR and OS.Results:
In univariate analysis, elevated N/L ratio was significantly associated with decreased TTR (hazard ratio (HR), 2.32; 95% confidence interval (CI), 1.30–4.14; P=0.005) and remained significant in the multivariate analysis (HR, 1.98; 95%CI, 1.05–3.71; P=0.035). Patients with elevated N/L ratio showed a median TTR of 77.9 months. In contrast, patients with low N/L ratio had a median TTR of 99.1 months. Regarding OS, elevated N/L ratio was also significantly associated with decreased survival in univariate analysis (HR, 2.90; 95%CI, 1.82–4.61; P=0.001) and remained significant in multivariate analysis (HR, 1.88; 95%CI, 1.14–3.12; P=0.014).Conclusion:
In conclusion, our findings suggest that an elevated preoperative N/L ratio predicts poor clinical outcome in STS patients and may serve as a cost-effective and broadly available independent prognostic biomarker. 相似文献193.
Jae Hong Im Thomas Tapmeier Lukxmi Balathasan Annamaria Gal Sabira Yameen Sally Hill Sean Smart Olivier Noterdaeme Matthew Kelly Michael Brady Weili Fu Karoline Kruse Eric J. Bernhard Hellmut G. Augustin Ruth J. Muschel 《International journal of cancer. Journal international du cancer》2013,132(2):315-326
Suppression of neo‐angiogenesis is a clinically used anti‐tumor strategy with new targets such as angiopoietin‐2 (Ang2) being proposed. However, the functions of Ang2 in vascular remodeling, inflammation and tumor growth are not consistent. We examined effect of depletion of host Ang2 on liver colony formation using Ang2 deficient (Ang2?/?) mice. Surprisingly, the metastatic colonies formed in Ang2?/? mice were larger than those in the wild type. These colonies had greater vascular density with more pericyte coverage than the vessels in liver colonies in the wild type. Liver VEGF concentration in both genotypes was equivalent, and thus, the differences appeared VEGF independent. However, after colony formation, the serum concentration of granulocyte‐colony stimulating factor (G‐CSF) and CXCL1 in Ang2?/? mice was 12 and 6 times greater than after colony formation in wild type. Increase of these two cytokines was associated with two times greater numbers of neutrophils recruited to the liver. Two times more Tie2+/CD11b+/CD31? cells were present in the tumors in Ang2?/? than in the wild type livers. These results suggest that the depletion of host Ang2 induced compensatory VEGF‐independent angiogenic mechanisms and thus enhanced liver metastatic colony growth and colony vascularity. They further indicate organotypic differences in response to tumor metastasis. In contrast, Ang2 deficiency inhibited tumor growth during metastatic colony formation in the lung, consistent with the reports of decreased pulmonary seeding of tumor cells after pharmacological inhibition of Ang2. Further studies are thus required to assess the effects of pharmacological Ang2 blockade for cancer patients particularly in the liver. 相似文献
194.
195.
Shingo Matsumoto Keita Saito Hironobu Yasui H. Douglas Morris Jeeva P. Munasinghe Martin Lizak Hellmut Merkle Jan Henrik Ardenkjaer‐Larsen Rajani Choudhuri Nallathamby Devasahayam Sankaran Subramanian Alan P. Koretsky James B. Mitchell Murali C. Krishna 《Magnetic resonance in medicine》2013,69(5):1443-1450
The hypoxic nature of tumors results in treatment resistance and poor prognosis. To spare limited oxygen for more crucial pathways, hypoxic cancerous cells suppress mitochondrial oxidative phosphorylation and promote glycolysis for energy production. Thereby, inhibition of glycolysis has the potential to overcome treatment resistance of hypoxic tumors. Here, EPR imaging was used to evaluate oxygen dependent efficacy on hypoxia‐sensitive drug. The small molecule 3‐bromopyruvate blocks glycolysis pathway by inhibiting hypoxia inducible enzymes and enhanced cytotoxicity of 3‐bromopyruvate under hypoxic conditions has been reported in vitro. However, the efficacy of 3‐bromopyruvate was substantially attenuated in hypoxic tumor regions (pO2 < 10 mmHg) in vivo using squamous cell carcinoma (SCCVII)‐bearing mouse model. Metabolic MRI studies using hyperpolarized 13C‐labeled pyruvate showed that monocarboxylate transporter‐1 is the major transporter for pyruvate and the analog 3‐bromopyruvate in SCCVII tumor. The discrepant results between in vitro and in vivo data were attributed to biphasic oxygen dependent expression of monocarboxylate transporter‐1 in vivo. Expression of monocarboxylate transporter‐1 was enhanced in moderately hypoxic (8–15 mmHg) tumor regions but down regulated in severely hypoxic (<5 mmHg) tumor regions. These results emphasize the importance of noninvasive imaging biomarkers to confirm the action of hypoxia‐activated drugs. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
196.
Bauernhofer T Pichler M Wieckowski E Stanson J Aigelsreiter A Griesbacher A Groselj-Strele A Linecker A Samonigg H Langner C Whiteside TL 《British journal of cancer》2011,104(10):1641-1648
Background:
The influence of human prolactin (hPRL) on the development of breast and other types of cancer is well established. Little information, however, exists on the effects of hPRL on squamous cell carcinomas of the head and neck (SCCHNs).Methods:
In this study, we evaluated prolactin receptor (PRLR) expression in SCCHN cell lines and assessed by immunohistochemistry the expression in 89 patients with SCCHNs. The PRLR expression was correlated with clinicopathological characteristics as well as clinical outcome. The effect of hPRL treatment on tumour cell growth was evaluated in vitro.Results:
Immunoreactivity for PRLR was observed in 85 out of 89 (95%) tumours. Multivariate COX regression analysis confirmed high levels of PRLR expression (>25% of tumour cells) to be an independent prognostic factor with respect to overall survival (HR=3.70, 95% CI: 1.14–12.01; P=0.029) and disease-free survival (P=0.017). Growth of PRLR-positive cancer cells increased in response to hPRL treatment.Conclusion:
Our data indicate that hPRL is an important growth factor for SCCHN. Because of PRLR expression in a vast majority of tumour specimens and its negative impact on overall survival, the receptor represents a novel prognosticator and a promising drug target for patients with SCCHNs. 相似文献197.
198.
199.
Felcht M Luck R Schering A Seidel P Srivastava K Hu J Bartol A Kienast Y Vettel C Loos EK Kutschera S Bartels S Appak S Besemfelder E Terhardt D Chavakis E Wieland T Klein C Thomas M Uemura A Goerdt S Augustin HG 《The Journal of clinical investigation》2012,122(6):1991-2005
Angiopoietin-2 (ANG-2) is a key regulator of angiogenesis that exerts context-dependent effects on ECs. ANG-2 binds the endothelial-specific receptor tyrosine kinase 2 (TIE2) and acts as a negative regulator of ANG-1/TIE2 signaling during angiogenesis, thereby controlling the responsiveness of ECs to exogenous cytokines. Recent data from tumors indicate that under certain conditions ANG-2 can also promote angiogenesis. However, the molecular mechanisms of dual ANG-2 functions are poorly understood. Here, we identify a model for the opposing roles of ANG-2 in angiogenesis. We found that angiogenesis-activated endothelium harbored a subpopulation of TIE2-negative ECs (TIE2lo). TIE2 expression was downregulated in angiogenic ECs, which abundantly expressed several integrins. ANG-2 bound to these integrins in TIE2lo ECs, subsequently inducing, in a TIE2-independent manner, phosphorylation of the integrin adaptor protein FAK, resulting in RAC1 activation, migration, and sprouting angiogenesis. Correspondingly, in vivo ANG-2 blockade interfered with integrin signaling and inhibited FAK phosphorylation and sprouting angiogenesis of TIE2lo ECs. These data establish a contextual model whereby differential TIE2 and integrin expression, binding, and activation control the role of ANG-2 in angiogenesis. The results of this study have immediate translational implications for the therapeutic exploitation of angiopoietin signaling. 相似文献
200.
Elise Langenkamp Lei Zhang Agata Zieba Henriikka Salomäki Martin Teichert Hua Huang Per‐Henrik Edqvist Theo Kraus Hellmut G Augustin Tommie Olofsson Erik Larsson Ola Söderberg Grietje Molema Fredrik Pontén Patrik Georgii‐Hemming Irina Alafuzoff Anna Dimberg 《The Journal of pathology》2012,228(3):378-390