Journal of Experimental & Clinical Cancer Research - Most viewed articles

Nuclear Receptor Interaction Protein (NRIP) expression assay using human tissue microarray and immunohistochemistry technology confirming nuclear localization

2008-08-02

Background: A novel human nuclear receptor interaction protein (NRIP) has recently been discovered by Chen SL et al, which may play a role in enhancing the transcriptional activity of steroid nuclear receptors in prostate (LNCaP) and cervical (C33A) cancer cell lines. However, knowledge about the biological functions and clinical implications of NRIP, is still incomplete. Our aim was to determine the distribution of NRIP expression and to delineate the cell types that express NRIP in various malignant tumors and healthy non-pathological tissues. This information will significantly affect the exploration of its physiological roles in healthy and tumor cells. Methods: By using tissue microarray (TMA) technology and an anti-NRIP monoclonal antibody immunohistochemical (IHC) survey, NRIP expression was examined in 48 types of tumors and in a control group of 48 matched or unmatched healthy non-neoplastic tissues. Results: Our survey results showed that ten cases were revealed to express the NRIP in six malignancies (esophageal, colon, breast, ovarian, skin, and pancreatic cancers), but not all of these specific tumor types consistently showed positive NRIP expression. Moreover, malignant tumors of the stomach, prostate, liver, lung, kidney, uterine cervix, urinary bladder, lymph node, testis, and tongue revealed no NRIP expression. Among the control group of 48 matched and unmatched non-neoplastic tissues, all of them demonstrated IHC scores less than the cut-off threshold of 3. In addition, ten cores out of thirty-six carcinomatous tissues revealed positive NRIP expression, which indicated that NRIP expression increases significantly in carcinoma tissue cores, comparing to the matched controlled healthy tissues. Conclusion: This is the first study to use a human TMA and IHC to validate the nuclear localization for this newly identified NRIP expression. In considering the use of NRIP as a potential diagnostic tool for human malignancies survey, it is important to note that NRIP expression carries a sensitivity of only 23%, but has a specificity of 100%. There is also a significant difference in positive NRIP expression between primary carcinomatous tissues and matched controlled healthy tissues. Although further large-scale studies will merit to be conducted to evaluate its role as a potential adjunct for cancer diagnosis, data from this study provides valuable references for the future investigation of the biological functions of NRIP in humans.

Increased chemotactic migration and growth in heparanase-overexpressing human U251n glioma cells

2008-07-22

Heparanase is an endoglycosidase that degrades heparan sulfate, the main polysaccharide constituent of the extracellular matrix (ECM) and basement membrane. Expression of the heparanase gene is associated with the invasion and metastatic potential of a variety of tumor-derived cell types. However, the roles of heparanase in the regulation of gene expression and the subsequent cell function changes other than invasion are not clear. In the current study, we overexpressed the human heparanase gene in a human U251n glioma cell line. We found that heparanase-overexpression significantly increased cell invasion, proliferation, anchorage-independent colony formation and chemotactic migration towards fetal bovine serum (FBS)-supplied medium and stromal cell-derived factor-1 (SDF-1). These phenotypic appearances were accompanied by enhanced protein kinase B (AKT) phosphorylation. Focal adhesion kinase (FAK) and extracellular signal-regulated kinase 1 (ERK1) signaling were not altered by heparanase-overexpression. These results indicate that heparanase has pleiotropic effects on tumor cells.

Promoter polymorphisms of DNMT3B and the risk of colorectal cancer in Chinese: a case-control study

Hong Fan, Feng Zhang, Jiabo Hu, Dongsheng Liu and Zhujiang Zhao — 2008-07-28

Background: DNA-methyltransferase-3B (DNMT3B), which plays a role in DNA methylation, is usually aberrant expression involved in carcinogenesis. Polymorphisms of the DNMT3B gene may influence DNMT3B activity on DNA methylation in several cancers, thereby modulating the susceptibility to cancer. Methods: DNMT3B -579G>T genotypes and -149C>T were determined by PCR-RFLP and sequencing in 137 colorectal cancer patients and 308 controls matched for age and sex, who did not receive radiotherapy or chemotherapy for newly diagnosed and histopathologically confirmed colorectal cancer. The association between two SNPs of the DNMT3B promoter and the risk of the development of colorectal cancer was analyzed in a population of Chinese. Results: The allele frequency of -149C >T among patients and controls was 0.73% versus 0.65%, respectively. The allele frequency of -597G>T for patients and controls was 6.57% versus 11.53%, respectively. Individuals with at least one -149C>T allele were no at a significantly increase risk of colorectal cancer compared with those having a -149TT genotype. However, Individuals with at least one 579G>T allele were decreased risk of colorectal cancer compared with those having a -579TT genotype. Conclusion: The relative distribution of -149C>T DNMT3B SNPs among a Chinese population can not be used as a stratification marker to predict an individual's susceptibility to colorectal cancer. However, the DNMT3B -579G>T polymorphism may contribute to the genetic susceptibility to colorectal cancer.

Low-molecular-weight heparins are superior to vitamin K antagonists for the long term treatment of venous thromboembolism in patients with cancer: a cochrane systematic review

2008-07-18

Background: Cancer and its therapies increase the risk of venous thromboembolism. Compared to patients without cancer, patients with cancer anticoagulated for venous thromboembolism are more likely to develop recurrent thrombotic events and major bleeding. Addressing all important outcomes including harm is of great importance to make evidence based health care decisions. The objective of this study was to compare low molecular weight heparin (LMWH) and oral anticoagulants (vitamin K antagonist (VKA) and ximelagatran) for the long term treatment of venous thromboembolism in patients with cancer. Methods: A systematic review of the medical literature. We followed the Cochrane Collaboration methodology for conducting systematic reviews. We assessed methodological quality for each outcome by grading the quality of evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. Results: Eight randomized controlled trials (RCTs) were eligible and reported data for patients with cancer. The quality of evidence was low for death and moderate for recurrent venous thromboembolism. LMWH, compared to VKA provided no statistically significant survival benefit (Hazard ratio (HR) = 0.96; 95% CI 0.81 to 1.14) but a statistically significant reduction in venous thromboembolism (HR = 0.47; 95% (Confidence Interval (CI) = 0.32 to 0.71). There was no statistically significant difference between LMWH and VKA in bleeding outcomes (RR = 0.91; 95% CI = 0.64 to 1.31) or thrombocytopenia (RR = 1.02; 95% CI = 0.60 to 1.74). Conclusion: For the long term treatment of venous thromboembolism in patients with cancer, LMWH compared to VKA reduces venous thromboembolism but not death.

Regulation of vascular endothelial growth factor expression by homeodomain-interacting protein kinase-2

Rosa Puca, Lavinia Nardinocchi and Gabriella D'Orazi — 2008-07-21

Background: Homeodomain-interacting protein kinase-2 (HIPK2) plays an essential role in restraining tumor progression as it may regulate, by itself or within multiprotein complexes, many proteins (mainly transcription factors) involved in cell growth and apoptosis. This study takes advantage of the recent finding that HIPK2 may repress the β-catenin transcription activity. Thus, we investigated whether HIPK2 overexpression may down-regulate vascular endothelial growth factor (VEGF) levels (a β-catenin target gene) and the role of β-catenin in this regulation, in order to consider HIPK2 as a tool for novel anti-tumoral therapeutical approaches. Methods: The regulation of VEGF expression by HIPK2 was evaluated by using luciferase assay with VEGF reporter construct, after overexpression of the β-catenin transcription factor. Relative quantification of VEGF and β-catenin mRNAs were assessed by reverse-transcriptase-PCR (RT-PCR) analyses, following HIPK2 overexpression, while β-catenin protein levels were evaluated by western immunoblotting. Results: HIPK2 overexpression in tumor cells downregulated VEGF mRNA levels and VEGF promoter activity. The VEGF downregulation was partly depending on HIPK2-mediated β-catenin regulation. Thus, HIPK2 could induce β-catenin protein degradation that was prevented by cell treatment with proteasome inhibitor MG132. The β-catenin degradation was dependent on HIPK2 catalytic activity and independent of p53 and glycogen synthase kinase 3β (GSK-3β) activities. Conclusion: These results suggest that VEGF might be a target of HIPK2, at least in part, through regulation of β-catenin activity. These findings support the function of HIPK2 as tumor suppressor and hypothesise a role for HIPK2 as antiangiogenic tool in tumor therapy approaches.

Non-protein coding RNA biomarkers and differential expression in cancers: a review

Massimo Mallardo, Palmiro Poltronieri and Oscar Fernando D'Urso — 2008-07-16

Background: In these years a huge number of human transcripts has been found that do not code for proteins, named non-protein coding RNAs. In most cases, small (miRNAs, snoRNAs) and long RNAs (antisense RNA, dsRNA, and long RNA species) have many roles, functioning as regulators of other mRNAs, at transcriptional and post-transcriptional level, and controlling protein ubiquitination and degradation. Various species of npcRNAs have been found differentially expressed in different types of cancer. This review discusses the published data and new results on the expression of a subset of npcRNAs. Conclusion: These results underscore the complexity of the RNA world and provide further evidence on the involvement of functional RNAs in cancer cell growth control.

The influence of survivin shRNA on the cell cycle and the invasion of SW480 cells of colorectal carcinoma

Liu Zhonghong, Lin Lianjie, Zheng Changqing, He Ying, Jin Yu and Lin Yan — 2008-07-18

Background: The objective was to understand the influence of Survivin plasmid with short hairpin RNA (shRNA) on the cell cycle, invasion, and the silencing effect of Survivin gene in the SW480 cell of colorectal carcinoma. Methods: A eukaryotic expression vector, PGCH1/Survivin shRNA, a segment sequence of Survivin as target, was created and transfected into colorectal carcinoma cell line SW480 by the non-lipid method. The influence on the Survivin protein was analyzed by Western blotting, while the cell cycle, cell apoptosis were analyzed by flow cytometry, and invasion of the cell was analyzed by Transwell's chamber method. Results: After the transfection of PGCH1/Survivin shRNA, the expression of Survivin protein in SW480 cells was dramatically decreased by 60.68%, in which the cells were stopped at G2/M phase, even though no apoptosis was detected. The number of transmembranous cells of the experimental group, negative control group, and blank control group were 14.46 ± 2.11, 25.12 ± 8.37, and 25.86 ± 7.45, respectively (P <0.05). Conclusion: Survivin shRNA could significantly reduce the expression of Survivin protein and invasion of SW480 cells. Changes in cell cycle were observed, but no apoptosis was induced.

Monitoring of people and workers exposure to the electric, magnetic and electromagnetic fields in an Italian national cancer Institute

2008-07-03

Background: The paper reports the electric, magnetic and electromagnetic fields (emf) measurements carried out in the Regina Elena National Cancer Institute (NCI). Several devices, used in diagnostics and in medical cures, can represent sources of emf for the workers and for the public subjected to the treatments. The aim is to evaluate their exposition, in order to assess the compliance with the law. Methods: The investigations have been carried out in the departments of: intensive care, physiotherapy, MR presstherapy and in the surgical rooms. The measurements have been performed using broad band probes in the frequency ranges 5 Hz÷30 kHz and 100 kHz-3 GHz. Results: The variability of the magnetic induction (B(μT)) levels is between 0,05 μT and 80 μT. The statistical distribution shows that most of the measurements are in the range 0,05

Comparison of methods to determine accurate dose calibrator activity measurements

2008-07-01
Background: In nuclear medicine, liquid radiopharmaceuticals for diagnostic or therapeutic purposes are administered to patients by using various types of syringes with different volumes. The activity of each "dose" must be carefully measured and documented prior to administration using an activity calibrator. Methods: Calibrator response is a function of the measurement geometry and, in particular, it depends on the syringe type and filling volume. To minimize the uncertainty associated with the measured activity of the syringe, it is necessary to calculate a calibration curve depending on filling volume for each syringe type. This curve can be obtained by fitting experimentally determined volume correction factors. Results: A theoretical evaluation of volume correction factors for syringes is reported for three different experimental methods. The aim is to determine the most accurate experimental method among those considered, by examining the expression of uncertainty for the correction factor. This theoretical analysis was then tested experimentally. Conclusion: The agreement between the experimental data obtained in the constant activity method and gravimetric method at constant specific activity and the small associated uncertainties show the accuracy of these two procedures; while the volumetric method at constant specific activity could lead to a wrong evaluation of the correction factors.

Dark Aberrant Crypt Foci with activated Wnt pathway are related to tumorigenesis in the colon of AOM-treated rat

Lu Qing, Jiang Bo, Chen Lin and Tao Shan — 2008-08-05
Backgroud : To evaluate the relationship between Aberrant Crypt Foci (ACF) and tumorigenesis, we observed the sequential development from ACF to tumor in the colon of azoxymethane-exposed wistar rats. Methods : Sixty wistar rats were sacrificed at different time points after exposure to azoxymethane and the colons were stained with methylene blue for stereomicroscopic analysis. Results : We found two types of early lesions: classic ACF and dark ACF. Dark ACF were characterized by having dark blue staining, mildly enlarged or small compressed crypts that are not elevated from the surrounding epithelium. Large dark ACF and nascent tumors displayed the same surface morphology. Furthermore, dark ACF grew significantly faster than classic ACF and showed dysplasia without hyperplasia. In contrast, classic ACF showed hyperplasia without dysplasia. Dark ACF has significant higher expression rate of beta-catenin (100%) and MMP-7 (81.82%) compared with the expression of beta-catenin and MMP-7 in classic ACF (4.84% and 7.87%, respectively). Conclusion : our data indicated that dark ACF is closely related to tumorigenesis while classic ACF is not. Furthermore, Wnt signal pathway was activated during the early period of dark ACF.