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Malignant Tumor Cells (malignant + tumor_cell)
Selected Abstracts99mTc-MIBI imaging for prediction of therapeutic effects of second-generation MDR1 inhibitors in malignant brain tumorsINTERNATIONAL JOURNAL OF CANCER, Issue 12 2007Toshio Sasajima Abstract The aim of this study was to explore whether 99mTc-methoxyisobutylisonitrile (99mTc-MIBI) is suitable to elucidate multidrug resistance and prediction of potentiation of antitumor agents by second-generation MDR1 inhibitors (PSC833, MS-209) in malignant brain tumors in rat. Malignant tumor cells (RG2 and C6 gliomas, Walker 256 carcinoma) were incubated with low dose vincristine (VCR) to induce multidrug resistance. MTT assay demonstrated a significant increase of surviving fractions in VCR-resistant sublines compared to those of drug-naive cells. Reverse transcriptase polymerase chain reaction revealed higher expression of MDR1 mRNA in VCR-resistant cells than drug-naive cells in each line. Volume distribution (Vd) of 99mTc-MIBI was negatively correlated with MDR1 mRNA expression among drug-naive and VCR-resistant cells. MDR1 inhibitors decreased surviving fractions and increased Vd of 99mTc-MIBI significantly in VCR-resistant sublines, whereas MDR1 mRNA expression was unchanged. These findings indicate that 99mTc-MIBI efflux was functionally suppressed by MDR1 inhibitors. Autoradiographic images of 99mTc-MIBI revealed higher uptake in drug-naive cells at basal ganglia compared with VCR-resistant cells at the opposite basal ganglia of rats. Oral administration of the second-generation MDR1 inhibitors significantly increased 99mTc-MIBI accumulation of both tumors. Therapeutic effects of VCR with or without the MDR1 inhibitors were also evaluated autoradiographically using 14C-methyl- L -methionine (14C-Met) and MIB-5 index. 14C-Met uptake and MIB-5 index of both tumors treated with VCR following the MDR1 inhibitor treatment significantly decreased compared with tumors treated with VCR alone. Analysis of 99mTc-MIBI accumulation is considered informative for detecting MDR1-mediated drug resistance and for monitoring the therapeutic effects of MDR1 inhibitors in malignant brain tumors. © 2007 Wiley-Liss, Inc. [source] High serum levels of YKL-40 in patients with squamous cell carcinoma of the head and neck are associated with short survivalINTERNATIONAL JOURNAL OF CANCER, Issue 4 2008Anne Roslind Abstract YKL-40 is a glycoprotein secreted by macrophages, neutrophils and malignant tumor cells. Elevated serum levels of YKL-40 are associated with poor prognosis in several malignancies. In this study, we examined the prognostic value of serum YKL-40 before treatment and during follow-up in patients with squamous cell carcinoma of the head and neck (HNSCC). YKL-40 was determined by ELISA retrospectively in serum from 173 patients with primary HNSCC before treatment and up to 2 years after treatment. Median follow-up time was 7.9 years. YKL-40 protein expression in tumor biopsies was assessed by immunohistochemistry in 50 patients. Pretreatment serum YKL-40 was elevated in 53%. Patients with high serum YKL-40 had shorter survival than patients with normal serum YKL-40 (33 vs. 84 months; p = 0.008). Multivariate Cox analysis including pretreatment serum YKL-40, age, sex, primary tumor site, TNM classification and treatment demonstrated that TNM classification (HR = 2.61, p = 0.02) and serum YKL-40 (log-transformed continuous variable: HR = 1.55, p < 0.0001) were independent prognostic variables of overall survival (OS). Multivariate Cox analysis demonstrated that TNM classification (HR = 5.77, p = 0.001) and serum YKL-40 (dichotomous variable: HR = 2.75, p = 0.01) were independent predictors of recurrence-free survival. During follow-up after radiotherapy, a high serum YKL-40 (log-transformed continuous variable) in patients with TNM Stage III and IV disease predicted poorer OS within 6 months (HR = 1.95, p < 0.0001). Immunohistochemical analysis showed YKL-40 expression in the malignant tumor cells. In conclusion, serum YKL-40 was demonstrated to be an independent prognostic biomarker of recurrence-free and overall survival in patients with HNSCC. © 2007 Wiley-Liss, Inc. [source] Proteomic profiling for cancer progression: Differential display analysis for the expression of intracellular proteins between regressive and progressive cancer cell linesPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 4 2005Eiko Hayashi Abstract Tumor development and progression consist of a series of complex processes involving multiple changes in gene expression (Paolo et al. Physiol. Rev., 1993, 73, 161,195; Lance et al. Cell., 1991, 64, 327,336). Tumor cells acquire an invasive and metastatic phenotype that is the main cause of death for cancer patients. Therefore, for early diagnosis and effective therapeutic intervention, we need to detect the alterations associated with transition from benign to malignant tumor cells on a molecular basis. To unravel alterations concerned with tumor progression, the proteomic approach has attracted great attention because it can identify qualitative and quantitative changes in protein composition, including post-translational modifications. In this study, we performed proteomic differential display analysis for the expression of intracellular proteins in the regressive cancer cell line QR-32 and the inflammatory cell-promoting progressive cancer cell line QRsP-11 of murine fibrosarcoma by two-dimensional gel electrophoresis and mass spectrometry using an Agilent 1100 LC/MSD Trap XCT. We found 11,protein spots whose expression was different between QR-32 and QRsP-11 cells and identified nine proteins, seven of which, calreticulin precursor, tropomyosin,1 , chain, annexin,A5, heat shock protein (HSP)90-,, HSP90-,, PEBP, and Prx,II, were over-expressed, and two, Anp32e and HDGF, which were down-regulated. The results suggest an important complementary role for proteomics in identification of molecular abnormalities in tumor progression. [source] Up-regulation of pro-inflammatory genes as adaptation to hypoxia in MCF-7 cells and in human mammary invasive carcinoma microenvironmentCANCER SCIENCE, Issue 4 2010Marco Tafani The role of tumor cells in synthesizing pro-inflammatory molecules is still controversial. Here we report that hypoxic treatment of the MCF-7 human mammary adenocarcinoma cell line induced activation of hypoxia-inducible factor 1, (HIF-1,) and nuclear factor-kappa B (NF-,B). Importantly, hypoxia regulated expression of alarmin receptors such as the receptor for advanced glycation end products (RAGE) and the purinoreceptor (P2X7R), and up-regulated inflammatory response (IR) genes such as the inducible enzymes nitric oxide synthase (NOS2), cycloxygenase (COX2), and the acute-phase protein pentraxin-3 (PTX3). Hypoxia also stimulated chemokine (C-X-C motif) receptor 4 (CXCR4) mRNA synthesis. In fact, the CXCR4 ligand stromal-derived factor-1, (SDF-1,) increased invasion and migration of hypoxic MCF-7 cells. Inhibition of HIF-1, by chetomin and NF-,B by parthenolide reduced mRNA and protein expression of the studied molecules and prevented invasion of hypoxic MCF-7 cells. Moreover, solid invasive mammary tumor microenvironment was analyzed after laser-capture microdissection (LCMD) comparing tumor versus host normal tissue. Nuclear translocation of HIF-1, and NF-,B and up-regulation of IR, CXCR4, estrogen receptor , (ER,), and epithelial growth factor receptor (EGFR) was observed in tumor but not in host normal tissue in the absence of a local inflammatory leukocyte infiltrate. We conclude that under hypoxic conditions MCF-7 cells acquire a pro-inflammatory phenotype, and that solid human mammary carcinoma evidenced a similar activation of HIF-1,, NF-,B, and IR genes in malignant tumor cells as compared to the normal host tissues. We suggest a role for IR activation in the malignant progression of transformed cells. (Cancer Sci 2010; 101: 1014,1023) [source] | ||||||||||