rapidSTRIPE H1N1 test for detection of the pandemic swine origin influenza A (H1N1) virus.

The rapidSTRIPE H1N1 test, based on a nucleic acid lateral-flow assay, has been developed for diagnosis of a swine-origin influenza A (H1N1) virus. This test is simple and cost-effective and allows specific detection of the S-OIV A (H1N1) virus from swab sampling to final detection on a lateral-flow stripe within 2 to 3 h.

Gene signatures of pulmonary metastases of renal cell carcinoma reflect the disease-free interval and the number of metastases per patient.

Our understanding of metastatic spread is limited and molecular mechanisms causing particular characteristics of metastasis are largely unknown. Herein, transcriptome-wide expression profiles of a unique cohort of 20 laser-resected pulmonary metastases (Mets) of 18 patients with clear-cell renal cell carcinoma (RCC) were analyzed to identify expression patterns associated with two important prognostic factors in RCC: the disease-free interval (DFI) after nephrectomy and the number of Mets per patient. Differentially expressed genes were identified by comparing early (DFI < or = 9 months) and late (DFI > or = 5 years) Mets, and Mets derived from patients with few (< or =8) and multiple (> or =16) Mets. Early and late Mets could be separated by the expression of genes involved in metastasis-associated processes, such as angiogenesis, cell migration and adhesion (e.g., PECAM1, KDR). Samples from patients with multiple Mets showed an elevated expression of genes associated with cell division and cell cycle (e.g., PBK, BIRC5, PTTG1) which indicates that a high number of Mets might result from an increased growth potential. Minimal sets of genes for the prediction of the DFI and the number of Mets per patient were identified. Microarray results were confirmed by quantitative PCR by including nine further pulmonary Mets of RCC. In summary, we showed that subgroups of Mets are distinguishable based on their expression profiles, which reflect the DFI and the number of Mets of a patient. To what extent the identified molecular factors contribute to the development of these characteristics of metastatic spread needs to be analyzed in further studies.

Biocompatibility of iron filled carbon nanotubes in vitro.

Due to their particular magnetic properties, nanoparticles of metallic iron are promising candidates for magnetic fluid hyperthermia when compared to the commonly used iron oxides. However, the difficulty of handling these structures in ambient conditions without oxidation hinders its practical application. In this work, iron filled carbon nanotubes non-covalently functionalized by human serum albumin are studied as potential agents for hyperthermia. Here the iron is encapsulated inside of the carbon shells and protected from reactions with its environment. Besides protecting the iron and biological environment against each other, the carbon shells can also work as an interface for conjugation with other biological molecules of interest. In order to assess if such structures could induce any toxic effect in human cell cultures, we have probed its biocompatibility on a dosage and time dependent manner by measuring metabolic activity, cell proliferation, cell cycle distribution and apoptosis. Our results have shown that those nanotubes strongly associate with cells within a short incubation period and do not pose any significant toxic effect. The magnetic properties of iron filled carbon nanotubes in biological environment, i.e., associated to cells, have been studied and a possible rotation as a function of the applied magnetic field is discussed. Our initial findings encourage the further study of these structures as potential hyperthermia agents.

Antisense-mediated inhibition of survivin, hTERT and VEGF in bladder cancer cells in vitro and in vivo.

Since cancer cells are characterised by multiple genetic alterations the single inhibition of one tumour- associated gene might not be sufficient as a therapeutic strategy. We examined the effects of a combined inhibition of survivin, human telomerase reverse transcriptase (hTERT) and vascular endothelial growth factor (VEGF) with antisense oligodeoxynucleotides (AS-ODNs) and small interfering RNAs (siRNAs) in EJ28 and 5637 bladder cancer (BCa) cells. Following verification of the uptake of intraperitoneally applied fluorescence-labelled AS-ODNs and siRNAs in subcutaneous BCa xenografts, the target-directed constructs were tested as single agents in SCID mice bearing subcutaneous EJ28. Simultaneous inhibition of two of the selected transcripts significantly enhanced cell viability reduction compared to the controls consisting of a target directed construct and an appropriate control construct without any homology to the human genome. The uptake of both antisense inhibitor types in the subcutaneous BCa was achieved even without a carrier. In vivo studies with 9 consecutive intraperitoneal injections with 20 mg/kg AS-ODNs or 4.6 mg/kg siRNAs revealed the biocompatibility of both antisense inhibitor types and showed anti-tumoural activity of the AS-ODNs used.

Multitarget siRNA inhibition of antiapoptotic genes (XIAP, BCL2, BCL-X(L)) in bladder cancer cells.

BACKGROUND: The knockdown of XIAP, BCL2 and BCL-X(L) by siRNAs represents a promising treatment option for bladder cancer (BCa) since the overexpression of antiapoptotic genes is often associated with tumor progression and treatment resistance. MATERIALS AND METHODS: EJ28 BCa cells were transfected with siRNAs--separately and combined--followed by analysis of target expression, viability, clonogenic survival, apoptosis and cell cycle. Furthermore, a possible chemosensitization by siRNA pretreatment was investigated. RESULTS: The siRNA-mediated inhibition of these targets--either separately or combined--reduced the targets' expression, reduced cell growth and sensitized cells to a subsequent chemotherapy. CONCLUSION: Since tumor cells may bypass the inhibition of a single gene by changing their expression profile, e.g. switch from BCL2 to BCL-X(L), the combined knockdown of multiple genes of the same pathway might be more effective in killing cancer cells. The siRNAs used represent appropriate tools for this aim since they reduced their targets' expression significantly and long-lastingly.

Telomerase inhibition by synthetic nucleic acids and chemosensitization in human bladder cancer cell lines.

The knockdown of genes that are over-expressed in cancer, and function in tumor onset and/or progression, is an attractive tool to impair the growth of tumor cells. Synthetic nucleic acids such as antisense oligodeoxynucleotides (AS-ODNs) or small-interfering RNAs (siRNAs) were applied against different tumor-associated transcripts, including the human telomerase reverse transcriptase (hTERT), to inhibit the proliferation of tumor cells and to sensitize them against chemotherapeutic (CT) agents. The efficacy of nucleic acid-based inhibitors was evaluated in vitro by determining the extent of down-regulation of the respective target mRNA and protein expression as well as by extensively investigating growth properties (e.g., viability, proliferation, apoptosis, and cell-cycle distribution) of the affected tumor cells. Methods for a successful down-regulation of hTERT and for the quantitative determination of resulting effects on cellular growth were described herein.

Elevated expression of survivin-splice variants predicts a poor outcome for soft-tissue sarcomas patients.

The aim of this study was to investigate the level and the prognostic value of the expression of different survivin transcript variants--survivin, survivin-DeltaEx3 and survivin-2B--in tumours of 76 soft tissue sarcoma (STS) patients. The expression of survivin transcript variants in STS tissue samples and in 12 nonmalignant control tissues was analysed by quantitative RT-PCRs. Expression levels of all survivin transcript variants were strongly elevated in STS compared to normal tissues. A positive correlation between expression of splice variants and tumour stage was found (P=0.02; chi2 test). The multivariate Cox's proportional hazards regression model revealed a 7.3-fold increased risk of tumour-related death for patients with survivin-DeltaEx3 overexpressing tumours (P=0.007). The effect of surivivin (wildtype variant) and survivin-2B was less pronounced but still significant (2.2- and 1.9-fold, resp., P<0.05 each). Our results show for the first time that mRNA expression of survivin-variants is significantly correlated to a poor prognosis for STS patients, and we suggest expression of survivin splice variants together with tumour stage as independent predictor of survival.

Transcript quantification of Dresden G protein-coupled receptor (D-GPCR) in primary prostate cancer tissue pairs.

Recently, we identified the novel protein D-GPCR (Dresden G protein-coupled receptor) which is selectively overexpressed in human prostate cancer (PCa) and belongs to the subfamily of odorant-like orphan GPCRs. Quantification of D-GPCR transcripts in paired malignant and non-malignant prostate tissues of 106 patients with primary PCa by real-time PCR demonstrated a significant up-regulation of this gene in tumor samples. Furthermore, its expression increases with higher tumor stages and grades. The evaluation of D-GPCR expression as a potential molecular tumor marker was performed by receiver-operating characteristic curve (ROC) analysis resulting in an area under the curve (AUC) value of 0.6452. Hence, the evaluation of D-GPCR as possible additive diagnostic tool and putative therapy target appears promising.

Chemosensitization of bladder cancer cells by survivin-directed antisense oligodeoxynucleotides and siRNA.

Survivin is known to be overexpressed in numerous tumor types including human bladder cancer and to cause resistance to radiation and chemotherapy. Therefore, we tested the antisense oligodeoxynucleotide AS-SVV286 and the small interfering RNA si-SVV284 to down-regulate survivin in the BCa cell lines EJ28 and 5637 thereby acting as sensitizers for chemotherapy. Pretreatment with these inhibitors followed by chemotherapy caused an enhanced decrease in cell viability. The observed reduction in cell counts associated with increased rates of apoptosis paralleled the degree of reduction of survivin expression that was achieved more efficiently by the siRNA than by the AS-ODN. Nevertheless, both therapy approaches in combination with all tested chemotherapeutics provoked a remarkable inhibition of viability and may serve as suitable additive tools for chemosensitization of bladder cancer cells.

Tissue factor and tumor: clinical and laboratory aspects.

This review summarizes data demonstrating the role of TF in tumor development, metastasis and angiogenesis. TF is a transmembrane protein that is expressed constitutively in some kinds of extravascular cells and transiently in intravascular cells after stimulation with cytokines and growth factors. Originally TF was considered to have a function in the initiation of coagulation. In the last years it became evident that TF plays a role in physiological and pathological processes outside the hemostasis. Up-regulation of TF expression appears to be characteristic of tumor tissue. In a variety of human tumors it was shown by immunohistochemistry, that TF can be expressed in malignant cells as well as in tumor-infiltrating macrophages or endothelial cells. Such abnormal TF expression contributes to the angiogenic process by a shift in the balance between endogenous proangiogenic and antiangiogenic factors. Observations of a significant correlation between elevated TF expression with increased microvessel density and VEGF expression underline the TF involvement in tumor angiogenesis. Furthermore, TF expression influences also metastasis. The effect of TF on metastasis may result from its angiogenic effect, but also from the production of growth factors or adhesion proteins.

Functional analyses of C13orf19/P38IP in prostate cell lines.

Human C13orf19 was previously identified to be downregulated in prostate cancer (PCa) but its function is unknown to date. In the present study, C13orf19 mRNA expression was inhibited by siRNA transfection. Furthermore, a possible regulation by androgens and the previously postulated interaction with p38 MAP kinase (p38MAPK) was investigated. The siRNA-mediated downregulation of the C13orf19 mRNA expression in the prostate cell lines PC-3 and BPH-1 was examined by quantitative PCR. Cellular viability, apoptosis, cell cycle distribution and clonogenic survival were investigated. In addition, the effects of C13orf19 downregulation in combination with chemotherapy on overall cell survival were studied. The inhibition of C13orf19 mRNA expression to 12% (after 12 h) and 55% (after 96 h) in PC-3 cells attested to a strong and persistent molecular effect provoked by the siRNA-D5 construct. However, no obvious effects on doubling time and cellular morphology were observed. Cell cycle distribution, clonogenic survival, apoptosis and cell viability showed no alterations, even after combining siRNA transfection with chemotherapy. Therefore, it can be concluded that the reduced expression of C13orf19 in PCa is not involved in the malignant transformation of the cells. A possible androgen dependence of C13orf19 mRNA expression was investigated by treating LNCaP cells with the androgen R1881 and in combination with the antiandrogen, bicalutamide. C13orf19 is expressed independently of the androgen. To analyze the putative interaction between C13orf19 and p38MAPK, PC-3 and BPH-1 cells were treated with the p38MAPK inhibitor, SB203580, and C13orf19 mRNA expression was examined. Additionally, the expression and phosphorylation status of p38MAPK after the inhibition of C13orf19 was investigated by Western blotting. No interaction between C13orf19 and p38MAPK was identified. Therefore, the gene should forthwith be named C13orf19 or Fam48A and not P38IP.

Prognostic relevance of uPAR-del4/5 and TIMP-3 mRNA expression levels in breast cancer.

Recently, two components of important protease systems in cancer, i.e., the urokinase plasminogen activator receptor (uPAR) mRNA splice variant uPAR-del4/5 and the tissue inhibitor of matrix metalloproteinase-3 (TIMP-3), were independently reported to be of prognostic value in breast cancer. In the present study, we have evaluated the impact of both these factors on disease-free survival (DFS) in 205 breast cancer patients by assessing mRNA expression in tumour tissue by quantitative PCR. High uPAR-del4/5 mRNA expression was associated with shorter DFS in breast cancer patients (P=0.0363), whereas high TIMP-3 mRNA levels were associated with a good prognosis (P=0.0049). Furthermore, by combining uPAR-del4/5 with TIMP-3 values, we demonstrate that breast cancer patients with high uPAR-del4/5 and low TIMP-3 mRNA levels had a highly significantly shorter DFS in comparison to those patients with low uPAR-del4/5 and high TIMP-3 mRNA expression (P<0.0001). These patients had a more than 6-fold higher risk for disease recurrence or death in multivariate analysis. Therefore, considering the prognostic impact of two proteolytic factors stemming from complementary protease systems may improve the prediction of disease recurrence in breast cancer.

Quantification of C13orf19/P38IP mRNA expression by quantitative real-time PCR in patients with urological malignancies.

Quantitative real-time PCR was performed for C13orf19, a gene located on chromosome 13q and previously described to be down-regulated in prostate carcinoma, on different cancer cell lines, on matched prostate tissues from 61 patients with prostate carcinoma and on matched kidney tissues from 23 patients with renal clear cell carcinoma. All data were normalized to glyceraldehyde-3-phosphate dehydrogenase (GAPDH), porphobilinogen deaminase (PBGD) and hypoxanthine guanine phosphoribosyl transferase (HPRT) mRNA expression. A C13orf19 quantitative PCR (QPCR) showed the mRNA to be down-regulated in matched prostate tissues (P=0.007 and lower, paired Student's t-test). However, an at least 1.5-fold C13orf19 mRNA downregulation was observed in samples from 28 patients (46%) and an at least 1.5-fold upregulation was observed in samples from 17 patients (28%). In contrast, C13orf19 mRNA alterations in expression seemed to be random events in kidney cancers.

Detection of circulating tumor cells from renal carcinoma patients: experiences of a two-center study.

Approximately 30-40% of primary and localized renal cell carcinoma (RCC) will eventually become metastatic disease. Therefore, the detection and molecular characterization of circulating tumor cells (CTC) in RCC may have important prognostic and therapeutic implications. Venous blood samples were obtained from a total of 214 RCC patients before and after nephrectomy or during adjuvant immune chemotherapy in two urological centers. After density gradient centrifugation, the CD45-negative cell population was isolated from peripheral blood samples (BS) by a semi-automated immunomagnetic depletion procedure using the MACS technology. Enriched cell populations potentially containing CTC were stained for cytokeratin and evaluated by a trained pathologist. CTC were found in 105 out of 363 BS (29%) originating from 80 out of 214 patients (37%). The median tumor cell number was five (range 1-51) per BS, i.e. approximately one CTC was detectable per 2-3 ml peripheral blood after tumor cell enrichment. For a subpopulation, follow-up data indicate that 62% of the patients with CTC detection in the blood developed progressive disease with single or multiple distant metastases or died because of RCC within two years. Here we show that the standardized immunomagnetic depletion protocol is a powerful tool for detecting and isolating intact RCC-derived CTC. The occurrence and the quantity of CTC in RCC patients is an early disease event. Furthermore, the occurrence of CTC is correlated with an advanced tumor stage and seems to be associated with a more aggressive tumor phenotype.

Antisense-mediated hTERT inhibition specifically reduces the growth of human bladder cancer cells.

PURPOSE: The expression of human telomerase reverse transcriptase (hTERT) is associated with cellular aging and tumorigenesis. It was found in nearly all cancer types but not in most normal, somatic cells. The aim of this study was to investigate whether hTERT inhibition by antisense oligodeoxynucleotides (AS-ODN) can act as an efficient strategy to specifically impair the growth of bladder cancer (BCa) cells in vitro. EXPERIMENTAL DESIGN: Twenty-three AS-ODNs were designed complementary to five putative single-stranded target sites using a computer-aided secondary structure prediction of hTERT mRNA. The BCa cell lines were transfected once or several times with AS-ODNs, and the influences on cell growth, hTERT mRNA, and hTERT protein levels, as well as on telomerase activity, were examined. RESULTS: An immediate and continuous reduction of cell viability (up to a complete cell loss) was achieved by treatment with 5 of 23 tested AS-ODNs in EJ28 cells. Additionally, significant inhibition of proliferation (doubling time, clonogenic survival), as well as an induction of G(1) arrest were observed. The specificity of the growth-inhibitory action of the five efficient AS-ODNs was confirmed by diminished hTERT transcript amount (< or =88%) and reduced hTERT protein content in EJ28 cells. As a consequence, the telomerase activity was inhibited by anti-hTERT treatment < or =60%. Inhibition of viability was shown for an additional three tested BCa cell lines but not for primary fibroblasts after treatment with the five most effective AS-ODNs supporting an antitumor action of these constructs. CONCLUSION: Specific hTERT inhibition causes remarkable short- and long-term effects on the growth of BCa cells and represents a promising new treatment option of solid tumors. We propose that this alternative treatment could be applied in terms of an instillation therapy.

Elevated expression level of survivin protein in soft-tissue sarcomas is a strong independent predictor of survival.

PURPOSE: Survivin is a member of the inhibitor-of-apoptosis gene family and is known to be overexpressed in a number of tumor types. The aim of this study was to evaluate the prognostic value of survivin protein expression in tumor tissue extracts in a group of well-characterized soft-tissue sarcoma (STS) patients. EXPERIMENTAL DESIGN: In this investigation, malignant tissue samples from 63 STS patients as well as from a panel of tumor cell lines were investigated, with nonmalignant tissues serving as controls. The survivin protein level was quantified by a novel ELISA and by Western blot analysis. Results obtained by both methods were compared with clinicopathological parameters regarding tumor grade and tumor entity, and they were then correlated to survival in a multivariate Cox regression model. RESULTS: High survivin levels were detected by ELISA and Western blot analysis in tumor tissue extracts and in lysates of tumor cell lines. None or only weak expression of survivin protein was found in nonmalignant cells and tissues. When comparing survivin values obtained by ELISA or Western blot, we found a significant correlation between both methods (P = 0.013, Pearson test). Our findings revealed that, in multivariate Cox regression analyses, survivin levels measured by ELISA and Western blot were significantly associated with tumor-related death in STS patients (P = 0.001, RR = 19.8, and P = 0.004, RR = 5.1, respectively). However, in a direct comparison of both survivin protein detection assays, we found a higher sensitivity and a stronger correlation to prognosis in survivin ELISA as compared with the Western blot assays. Furthermore, a higher tumor grade and more aggressive STS entity showed an elevated survivin protein expression level. CONCLUSION: Altogether, an elevated survivin content in tumor tissue extracts has a significant and independent negative predictive value on the survival-rate of STS patients. This finding corresponds well to data obtained for the mRNA level of survivin, as shown previously (M. Kappler et al., Int. J. Cancer, 95: 360-363, 2001).

Knockdown of survivin expression by small interfering RNA reduces the clonogenic survival of human sarcoma cell lines independently of p53.

Survivin, a member of the inhibitors-of-apoptosis gene family, is overexpressed in many tumor types. Survivin is a prognostic marker of soft-tissue sarcomas, but the downregulation of survivin expression and the possible dependency of survivin downregulation on p53 in these tumors have not been investigated. Therefore, we applied small interfering RNA (siRNA) to knock down the expression of survivin in five human sarcoma cell lines with wild-type or mutant p53 alleles. Compared with survivin mRNA expression in the nonsense siRNA-treated sarcoma cell lines, expression after treatment with survivin-specific siRNA was reduced by 73-88%; survivin protein expression was reduced by 52-81%. This finding was coupled with a reduction in clonogenic survival ranging from 65-86%. However, less than 10% of cells treated with survivin-specific siRNA underwent apoptosis. Cell-cycle and morphologic analyses showed that after a dramatic increase in the number of treated cells in the G2/M phase, some of the cells became polyploid; this result indicates that mitosis of a substantial number of treated cells was incomplete. Our findings suggest that survivin-specific siRNA could be a selective treatment to kill sarcoma cells regardless of the presence or absence of wild-type p53 alleles.

Identification of a novel urokinase receptor splice variant and its prognostic relevance in breast cancer.

The cellular receptor for urokinase-type plasminogen activator, uPAR, plays a central role in both cell surface-associated proteolysis and cellular adhesion. In the present study, we systematically searched for splice variants of uPAR mRNA in human cells and tumor tissues by qualitative RT-PCR using specific primers for uPAR exons 1 and 6. Beside the wild-type (wt) uPAR mRNA and the previously described splice variant lacking exon 5 (uPAR-del5), a novel splice variant lacking both exons 4 and 5 (uPAR-del4/5) was found predominantly in various cancer cell lines. To elucidate whether alternatively spliced uPAR mRNA may be translated and post-translationally processed, we generated stably transfected Chinese hamster ovary cells, which harbor expression plasmids of wt uPAR and various uPAR variants including uPAR-del5 and uPAR-del4/5. By ELISA, flow cytofluorometry, and Western blot analysis, we confirmed synthesis and secretion of wt uPAR and the uPAR variants by the use of domain-specific monoclonal antibodies against uPAR. For quantification of uPAR mRNA variants, we established two highly sensitive real-time RT-PCR assays based on LightCycler technology. Study of their expression in a representative set of breast cancer tissues indicated that the novel mRNA variant uPAR-del4/5 was expressed very frequently and independently of uPAR mRNA variants covering exon 4 (uPAR-wt and uPAR-del5). Higher uPAR-del4/5 expression was significantly associated with shorter disease-free survival (p = 0.0004) of breast cancer patients. These results suggest that uPAR-del4/5 mRNA may serve as a novel prognostic marker in breast cancer.

Antisense-mediated VEGF suppression in bladder and breast cancer cells.

Angiogenesis plays a key role in tumor growth and metastasis. Vascular endothelial growth factor (VEGF) is one of the major angiogenic factors. In the study we have evaluated the efficiency of antisense oligodeoxynucleotides (AS-ODN) against VEGF selected from computational prediction of VEGF mRNA structure. Twenty-five different AS-ODN in two different tumor cell lines were investigated. Treatment of cell line EJ28 by VEGF723 resulted in a 83.5% suppression of VEGF protein when compared with control-ODN. Three further AS-ODN reduced VEGF protein more than 45% in comparison to control-ODN. This was caused by an antisense-specific downregulation of the VEGF transcript determined by real-time PCR. Furthermore, antisense-mediated inhibition of VEGF was associated by a reduced cell viability. In MCF-7 cells VEGF protein was inhibited more than 45% by two AS-ODN. In conclusion, we found that computational prediction of potential single strand mRNA motifs is a well suitable method to elect effective AS-ODN.

Tissue specific expression and serum levels of human tissue factor in patients with urological cancer.

Human tissue factor (TF) is involved in tumor angiogenesis and metastasis. However, little is known about the distribution of TF in urological cancer. In this study we investigated the TF expression in tumor tissue and autologous non-malignant tissue as well as in serum of patients with renal cell carcinoma (RCC), bladder cancer, and prostate cancer (PCa). To study the distribution of TF in tumor tissue and in the surrounding non-malignant tissue, we measured TF protein by ELISA in tissue specimens obtained intraoperatively from 18 RCC, seven bladder cancer and six PCa patients. Differences in TF expression were found between tumor tissue and nonmalignant tissue for the three tumor types at the protein level (in the order RCC < bladder cancer < PCa). In all but one of the 18 RCC patients (94 %) higher TF protein level was observed in non-malignant tissue as compared to the tumor tissue. In addition, the relative TF mRNA expression analyzed by a quantitative RT-PCR assay in the same RCC tissue sample pairs was higher in 78% of non-malignant tissues in comparison to the tumor tissue specimens. Moreover, using enzyme linked immunosorbent assay the TF protein content was measured in serum samples of 66 patients with bladder cancer, 75 RCC patients and 157 PCa patients, and was compared with the TF serum level of 92 healthy volunteers. Whereas no differences were detected between normal volunteers and patients with PCa or RCC, patients with bladder cancer showed a significantly increased level of serum TF (P=0.0076). However, no causal association between TF levels in serum and TF content in tissue extracts for all three tumor types of urological tumors was found. Our results suggest that TF in non-malignant renal tissues was expressed at a higher level compared to the supposed de novo TF expression in RCC tissue specimens. This indicates a tumor-associated induction of TF expression in the TF-negative RCC progenitor cells. The increased serum TF levels are alike the reported higher urinary TF levels found in bladder cancer patients. The potential clinical relevance of this finding should be further elucidated.