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Transport Research Centre (CDV) owns a uniquely-constructed trailer in the Czech Republic which serves for road surface noise level measurement using the CPX dynamic method. It is specialised equipment which is in accordance with the ISO 11819-2 standard design used in the Czech Republic. Within the EU, the measurements using the CPX method are conducted by several, primarily research-focused, institutions. In order to determine whether CDV results are eligible for international comparisons, comparison noise level measurement using the CPX method was conducted in the Czech Republic during joint work on the CESTI project (TE01020168 - Centre for Effective and Sustainable Transport Infrastructure) between CDV and Eurovia Services s.r.o. The measurement was conducted by CDV using a specially-constructed trailer. Eurovia used a specially-modified regular road vehicle manufactured in France. Results of comparison measurements at 50 km/h show that the noise level was systematically higher on most surfaces analysed by the Eurovia company. The average difference in 14 measurements was 0.6 dB(A): as far as the measurement uncertainty is concerned, the acquired results are compatible.

Abstract Background Pancreatic cancer is still associated with devastating prognosis. Real progress in treatment options has still not been achieved. Therefore new models are urgently needed to investigate this deadly disease. As a part of this process we have established and characterized a new human pancreatic cancer cell line. Methods The newly established pancreatic cancer cell line PaCa 5061 was characterized for its morphology, growth rate, chromosomal analysis and mutational analysis of the K-ras, EGFR and p53 genes. Gene-amplification and RNA expression profiles were obtained using an Affymetrix microarray, and overexpression was validated by IHC analysis. Tumorigenicity and spontaneous metastasis formation of PaCa 5061 cells were analyzed in pfp-/-/rag2-/- mice. Sensitivity towards chemotherapy was analysed by MTT assay. Results PaCa 5061 cells grew as an adhering monolayer with a doubling time ranging from 30 to 48 hours. M-FISH analyses showed a hypertriploid complex karyotype with multiple numerical and unbalanced structural aberrations. Numerous genes were overexpressed, some of which have previously been implicated in pancreatic adenocarcinoma (GATA6, IGFBP3, IGFBP6), while others were detected for the first time (MEMO1, RIOK3). Specifically highly overexpressed genes (fold change > 10) were identified as EGFR, MUC4, CEACAM1, CEACAM5 and CEACAM6. Subcutaneous transplantation of PaCa 5061 into pfp-/-/rag2-/- mice resulted in formation of primary tumors and spontaneous lung metastasis. Conclusion The established PaCa 5061 cell line and its injection into pfp-/-/rag2-/- mice can be used as a new model for studying various aspects of the biology of human pancreatic cancer and potential treatment approaches for the disease.

Background: More than 95% of cervical cancers and their precancerous lesions are caused by human papillomavirus (HPV). Cell-free (cf) HPV DNA detection in blood samples may serve as a monitoring tool for cervical cancer., Methods: In our methodological study, an HPV panel for simultaneous detection of 24 types using mass spectrometry-based analysis was developed for liquid biopsy approaches and tested on HPV positive cell lines, plasmid controls, and cervical high-grade squamous intraepithelial lesions (HSIL) in positive smear samples (n = 52). It was validated in cfDNA blood samples (n = 40) of cervical cancer patients., Results: The HPV panel showed proficient results in cell lines and viral plasmids with a limit of detection of 1 IU (international units)/µL for HPV16/18 and 10GE/µL for HPV11/31/33/39/45/51/52/58/59 and a specificity of 100% for the tested HPV types. In cervical smear samples, HPV DNA was detected with a sensitivity of 98.14%. The overall agreement between the new HPV panel and clinical records was 97.2% (κ = 0.84). In cervical cancer cfDNA, 26/40 (65.0%) tested positive for any HPV type, with most infections due to hrHPV (24/26). HPV positive samples were found in all FIGO stages, with the highest positivity ratio in FIGO III and IV. Even the lowest stage, FIGO I, had 12/23 (52.2%) patients with a positive HPV plasma status., Conclusions: This proof-of-concept paper shows that the described assay produces reliable results for detecting HPV types in a multiplex mass spectrometry-based assay in cervical smear and cfDNA with high specificity and sensitivity in both cohorts. The assay shows potential for liquid biopsy-based applications in monitoring cervical cancer progression., (© Association for Diagnostics & Laboratory Medicine 2024. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Human papilloma virus (HPV) is an infectious carcinogenic agent. Nearly all cervical cancers are positive for one of the high-risk HPV subtypes. Although the introduction of the HPV vaccines in many countries have shown tremendous positive effects on the incidence of both cervical intraepithelial lesions (CIN) and invasive cancer, the large majority of females worldwide are still not vaccinated. Patients with diagnosed high-grade CIN need a lifelong close monitoring of possible relapse or development of invasive cancer. Different blood-based liquid biopsy approaches have shown great promise as an easily obtainable minimally invasive tool for early detection and monitoring of disease. Among the different liquid biopsy approaches the clinical relevance of cell-free DNA (cfDNA) in cervical cancer has been best investigated. In cervical cancer, the DNA fragments can be of both, human as well as viral origin. Thus, the mutation and methylation status of genes related to carcinogenesis as well as the HPV status can be analysed in plasma from cervical cancer patients. This review describes recent advances in different cfDNA approaches for early detection and monitoring of cervical cancer and its precursor lesions., (© 2022. The Author(s).)

Cervical cancer is the fourth most common cancer in women, which is associated in >95% with a high-risk human papillomavirus (HPV) infection. Methylation of specific genes has been closely associated with the progress of cervical high-grade dysplastic lesions to invasive carcinomas. Therefore, DNA methylation has been proposed as a triage for women infected with high-risk HPV. Methylation analyses of cervical cancer tissue have shown that cell adhesion molecule 1 (CADM1) and myelin and lymphocyte protein (MAL) methylation are present in over 90% of all cervical high-grade neoplasias and invasive cervical cancers. Here, we established a liquid biopsy-based assay to detect MAL and CADM1 methylation in cell free (cf)DNA of cervical cancer. Methylation of the target gene was validated on bisulfite converted smear-DNA from cervical dysplasia patients and afterward applied to cfDNA using quantitative real-time PCR. In 52 smears, a combined analysis of CADM1 and/or MAL (CADM1/MAL) showed methylation in 86.5% of the cases. In cfDNA samples of 24 cervical cancer patients, CADM1/MAL methylation was detected in 83.3% of the cases. CADM1/MAL methylation was detected already in 81.8% of stage I-II patients showing the high sensitivity of this liquid biopsy assay. In combination with a specificity of 95.5% towards healthy donors (HD) and an area under the curve (AUC) of 0.872 in the receiver operating characteristic (ROC) analysis, CADM1/MAL cfDNA methylation detection might represent a novel and promising liquid biopsy marker in cervical cancer.

Monitoring of pollution in the vicinity of roads connected to winter road maintenance is one of the important tools for optimising winter maintenance technology and reducing its environmental impact. The aim of this study was to determine the relationship between winter road maintenance and the increased concentration of sodium ion to characterise the harm caused by the de-icing agents on selected types of individual components grown in the Norway spruce ecosystem. The model area is located in the immediate vicinity of the D1 motorway connecting Prague and Brno (Czech Republic), at 103 km. The area is thus exposed to long-term contamination from automobile transport, and the monitoring was carried out for 3 consecutive years. A clear effect of the de-icing agents on conifers near the road has been demonstrated by the symptoms of salt damage visually observed in close proximity to the road (at a sampling distance of 5 m). The needles of these spruce trees also showed increased sodium concentrations, regardless of the age of the needles. The study also confirms that sodium accumulates in all selected components of the analysed ecosystem (moos, humus, soil). The sodium concentration has been found to decrease with increasing distance from the road for all of the components., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

This study aims to compare the Hamburg Glasgow Classification (HGC) to Union for International Cancer Control (UICC) classification in patients with pancreatic ductal adenocarcinoma (PDAC). As adequate tumor classification is only possible after tumor resection and histological evaluation, only 20% of patients with PDAC receive accurate tumor staging. Thus, an accurate preoperative staging system is still missing but urgently needed. Systemic inflammation and tumor dissemination are important factors regarding the oncological outcome. HGC integrates both into a preoperative staging system, by combining C-reactive protein (CRP), albumin, and disseminated tumor cells (DTC) in the bone marrow. In this prospective study, 109 patients underwent surgical exploration for suspected PDAC. All patients underwent a preoperative bone marrow aspiration for DTC detection. HGC showed significant preoperative risk stratification for overall survival (OS) ( p -value < 0.001) and progression-free survival (PFS) ( p -value < 0.001). These results were comparable to the UICC survival stratification for OS and PFS ( p -value = 0.001 and 0.006). Additionally, in non-metastatic PDAC, HGC III-IV was associated with shorter OS and PFS ( p -value < 0.001, respectively) when compared to HGC I-II. Therefore, the HGC is a promising preoperative prognostic staging classification for accurate and simple outcome stratification in patients with PDAC.

Introduction: Current modalities to predict tumor recurrence and survival in esophageal cancer are insufficient. Even in lymph node-negative patients, a locoregional and distant relapse is common. Hence, more precise staging methods are needed. So far, only the CellSearch system was used to detect circulating tumor cells (CTC) with clinical relevance in esophageal cancer patients. Studies analyzing different CTC detection assays using advanced enrichment techniques to potentially increase the sensitivity are missing., Methods: In this single-center, prospective study, peripheral blood samples from 90 esophageal cancer patients were obtained preoperatively and analyzed for the presence of CTCs by Magnetic Cell Separation (MACS) enrichment (combined anti-cytokeratin and anti-epithelial cell adhesion molecules (EpCAM)), with subsequent immunocytochemical staining. Data were correlated with clinicopathological parameters and patient outcomes., Results: CTCs were detected in 25.6% (23/90) of the patients by combined cytokeratin/EpCAM enrichment (0-150 CTCs/7.5 mL). No significant correlation between histopathological parameters and CTC detection was found. Survival analysis revealed that the presence of more than two CTCs correlated with significantly shorter overall survival (OS) and progression-free survival (PFS)., Conclusion: With the use of cytokeratin as an additional enrichment target, the CTC detection rate in esophageal cancer patients can be elevated and displays the heterogeneity of cytokeratin (CK) and EpCAM expression. The presence of >2CTCs correlated with a shorter relapse-free and overall survival in a univariate analysis, but not in a multivariate setting. Moreover, our results suggest that the CK7/8 + /EpCAM + or CK7/8 + /EpCAM - CTC subtype does not lead to an advanced tumor staging tool in non-metastatic esophageal cancer (EC) patients.

Background: Pathological routine lymph node staging is postulated to be the main oncological prognosticator in esophageal cancer (EC). However, micrometastases in lymph nodes (LNMM) and bone marrow (BNMM) are discussed as the key events in tumor recurrence. We assessed the prognostic significance of the LNMM/BNMM status in initially pN0 staged patients with curative esophagectomy., Methods: From 110 patients bone marrow aspirates and lymph node tissues were analyzed. For LNMM detection immunohistochemistry was performed using the anticytokeratin antibody AE1/AE3. To detect micrometastases in the bone marrow a staining with the pan-keratin antibody A45-B/B3 was done. Results were correlated with clinicopathologic parameters as well as recurrence and death during follow-up time., Results: Thirty-eight (34.5%) patients showed LNMM, whereas in 54 (49.1%) patients BNMM could be detected. LNMM and BNMM positive patients showed a correlation to an increased pT category ( p = 0.017). Univariate and multivariate analyses revealed that the LNMM/BNMM status and especially LNMM skipping the anatomical lymph node chain were significant independent predictors of overall survival and recurrence-free survival., Conclusions: This study indicates that routine pathological staging of EC is insufficient. Micrometastases in lymph nodes and the bone marrow seem to be the main reason for tumor recurrence and they are a strong prognosticator following curative treatment of pN0 EC., Competing Interests: The datasets analyzed in the current study are not publicly available because they contain information that could compromise the investigated patients but are available from the corresponding author on reasonable request.

Background/aim: The clinical significance of circulating tumor cells (CTC) in non-metastatic esophageal cancer (EC) remains controversial and the cellular and molecular characteristics of CTCs are poorly understood. Especially the frequency and oncological impact of HER2 expression in CTCs in patients with EC have not been evaluated until now., Materials and Methods: In this single-center, prospective study, peripheral blood samples were obtained preoperatively from 45 patients who were diagnosed with resectable EC. CTC detection and HER2 expression were performed using the CellSearch System. Data were correlated with clinicopathological parameters and patient outcomes., Results: The study included 13 patients with squamous cell carcinomas (SCC) and 32 patients with adenocarcinomas (AC). HER2 gene amplification in the primary tumor was detected in 9.1% of patients. One or more CTCs were detected in 15.6% (SCC 1/13; AC 6/32) of the patients. None of the detected CTCs showed HER2 expression. Patients with CTCs showed significantly shorter relapse-free (p<0.001) and overall survival (p=0.015) than CTC-negative patients., Conclusion: This is the first study analyzing HER2 expression and the clinical significance of CTCs in patients with non-metastatic EC using an automated immunomagnetic detection system. HER2 expression in CTCs is very rare in patients with non-metastatic EC and seems to have a low clinical and oncological impact., (Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

For better lung cancer diagnosis and therapy, early detection markers of tumor dissemination are urgently needed, as most lung cancers do not show symptoms until extensive metastasis formation has already taken place. Our previous studies showed that in non-small cell lung cancer (NSCLC) early tumor dissemination is associated with a loss of chromosome 4q12-q32 and the presence of disseminated tumor cells (DTC) in the bone marrow. In order to identify the potential target gene in this region, a screen for methylation-dependent expression was performed. Lung cancer cell lines showing a loss of 4q as well as a normal bronchial epithelial cell line as control were treated with 5-aza-2'-deoxycytidine (5-aza-CdR) followed by expression profiling. Seven genes within the 4q target region, which have been associated with a positive DTC status before were found to be regulated by hypermethylation. QRT-PCR in an independent sample set identified HERC5 as a potential target gene. Quantitative methylation analysis of these lung tissue samples revealed that HERC5 promoter hypermethylation was significantly associated with positive DTC status (p = 0.020) and occurrence of brain metastases (p = 0.015). In addition, hypermethylation of the HERC5 promoter in NSCLC was identified as a predictor for poor survival for Stage I adenocarcinoma patients (p = 0.022) and also for poor overall survival in metastatic lung cancer patients (p = 0.028). In conclusion, HERC5 may function as a prognostic marker and is associated with tumor dissemination in lung cancer., (© 2014 UICC.)

This study was performed to assess the prognostic relevance of genomic aberrations at chromosome 4q in NSCLC patients. We have previously identified copy number changes at 4q12-q32 to be significantly associated with the early hematogenous dissemination of non-small cell lung cancer (NSCLC), and now aim to narrow down potential hot-spots within this 107 Mb spanning region. Using eight microsatellite markers at position 4q12-35, allelic imbalance (AI) analyses were performed on a preliminary study cohort (n = 86). Positions indicating clinicopathological and prognostic associations in AI analyses were further validated in a larger study cohort using fluorescence in situ hybridization (FISH) in 209 NSCLC patients. Losses at positions 4q21.23 and 4q22.1 were shown to be associated with advanced clinicopathological characteristics as well as with shortened disease free (DFS) and overall survival (OS) (DFS: P = 0.019; OS: P = 0.002). Multivariate analyses identified the losses of 4q21.23-22.1 to be an independent prognostic marker for both DFS and OS in NSCLC (HR 1.64-2.20, all P<0.04), and especially in squamous cell lung cancer (P<0.05). A case report study of a lung cancer patient further revealed a loss of 4q21.23 in disseminated tumor cells (DTCs). Neither gains at the latter positions, nor genomic aberrations at 4q12, 4q31.2 and 4q35.1, indicated a prognostic relevance. In conclusion, our data indicate that loss at 4q21.23-22.1 in NSCLC is of prognostic relevance in NSCLC patients and thus, includes potential new tumor suppressor genes with clinical relevance.

The expression of the activated leukocyte cell adhesion molecule (ALCAM and CD166) is increased in various types of cancer. We aimed to evaluate its role as a prognostic marker for esophageal cancer (EC). We retrospectively analyzed ALCAM expression in 299 primary lesions, 147 lymph node and 46 distant metastases from EC patients, on a tissue microarray using immunohistochemistry. Bone marrow samples from representative cancer patients (n = 16), taken before primary surgery, were stained by double-immunofluorescence for ALCAM and cytokeratins (CK). Blood serum samples from 236 cancer patients and 127 controls were analyzed for serum ALCAM (s-ALCAM) by ELISA. The immunohistochemical analysis showed increased ALCAM expression in the majority of lesions (primary tumor 71%, lymph node 76% and distant metastases 80%). ALCAM expression was not associated with histopathological parameters except for tumor grading (p = 0.015). ALCAM-positive patients had significantly worse recurrence-free and overall survival (OS; p = 0.002). Disseminated tumor cells (DTC) in bone marrow showed two phenotypes, ALCAM+/CK+ (36%) and ALCAM-/CK+ (64%). Multivariate analysis revealed that ALCAM expression and elevated s-ALCAM serum values are powerful prognostic variables for OS in patients with EC (hazard ratio [HR] 3.987, 95% confidence interval [95%CI] 1.906-8.340, p < 0.001 and HR 1.915, 95%CI 1.021-3.592, p = 0.043). The results of our study provide preliminary evidence for the potential clinical utility of ALCAM as a prognostic biomarker for EC, which might be a basis for future clinical application. In addition, ALCAM expression in a subset of DTC of the bone marrow indicates a potential function in the metastatic cascade of EC., (Copyright © 2011 UICC.)

A functional linkage of the structurally unrelated receptors HER2 and CXCR4 has been suggested for breast cancer but has not been evaluated for esophageal carcinoma. The inhibition of HER2 leads to a reduction of primary tumor growth and metastases in an orthotopic model of esophageal carcinoma. The chemokine receptor CXCR4 has been implicated in metastatic dissemination of various tumors and correlates with poor survival in esophageal carcinoma. The aim of this study was to investigate a correlation between the expression levels of HER2 and CXCR4 and to evaluate the involvement of CXCR4-expression in HER2-positive esophageal carcinoma. The effects of HER2-inhibition with trastuzumab and of CXCR4-inhibition with AMD3100 on primary tumor growth, metastatic homing, and receptor expression were evaluated in vitro and in an orthotopic model of metastatic esophageal carcinoma using MRI for imaging. The clinical relevance of HER2- and CXCR4-expression was examined in esophageal carcinoma patients. A significant correlation of HER2- and CXCR4-expression in primary tumor and metastases exists in the orthotopic model. Trastuzumab and AMD3100 treatment led to a significant reduction of primary tumor growth, metastases and micrometastases. HER2-expression was significantly elevated under AMD3100 treatment in the primary tumor and particularly in the metastases. The positive correlation between HER2- and CXCR4-expression was validated in esophageal cancer patients. The correlation of CXCR4- and HER2-expression and the elevation of HER2-expression and reduction of metastases through CXCR4-inhibition suggest a possible functional linkage and a role in tumor dissemination in HER2-positive esophageal carcinoma.

Background: Chemokines and their receptors are known to play important roles in the tumorigenesis of many malignancies. The aim of this study was to evaluate the prognostic impact of the expression of the chemokine receptors CXCR4 and CXCR7 in patients with pancreatic adenocarcinoma (PAC)., Methods: Expression of CXCR4 and CXCR7 in specimens from 249 patients with PAC was evaluated by immunohistochemistry on a tissue microarray and matched with clinicopathological parameters and overall survival., Results: Expression of CXCR4 was detected in 215 patients (86.4%) and CXCR7 in 47 patients (18.9%). No association between CXCR4 and CXCR7 expression was evident, although all the CXCR7 positive tumors were also CXCR4 positive. pT1/2 tumors showed a higher frequency of CXCR7 expression than pT3/4 tumors (P = 0.018), while more dedifferentiated tumors had elevated CXCR7 expression (P = 0.036). Overall and disease-free survival revealed no association with either CXCR4 or CXCR7 expression., Conclusion: CXCR7 is associated with tumor grade and inversely associated with tumor size and may play a potential role in tumor progression and differentiation. In contrast to previously reported data our results revealed no significant association between CXCR4 expression and clinical or pathological data., (Copyright © 2011 Wiley-Liss, Inc.)

Background: Genetic variations in cancer patients may serve as important prognostic indicators of clinical outcome. The GNAS1 T393C single nucleotide polymorphism (SNP) diversely correlates with the clinical outcome in cancer. The aim of this study was to evaluate the potential prognostic value of T393C-SNP in complete resected only surgically treated esophageal cancer (EC)., Methods: Genomic DNA was extracted from peripheral blood leucocytes of 190 patients who underwent only complete surgical resection for EC. T393C-SNP was correlated with clinic-pathological parameters, tumor cell dissemination in bone marrow (DTC) and clinical outcome., Results: T-allele carriers had more advanced disease due to presence of lymph node metastasis (P < 0.0001) and DTC (P = 0.01) and higher recurrence rate (P = 0.01) compared to CC genotype. The disease-free (P < 0.001) and overall survival (P < 0.001) was better in CC compared to TT and TC patients. In the multivariate Cox regression disease-stage adjusted analysis the T393C-SNP was identified as a strong independent prognostic factor for recurrence (hazard ratio 1.8, P = 0.01) and survival (hazard ratio 2.5, P < 0.001) in EC patients., Conclusion: Determination of T393C-SNP preoperatively will allow allocation of EC patients into different risk profiles which may help to stratify patients eligible for neoadjuvant and or adjuvant therapy.

Spliceosome assembly requires several structural rearrangements to position the components of the catalytic core. Many of these rearrangements involve successive strengthening and weakening of different RNA:RNA and RNA:proteins interactions within the complex. To gain insight into the organization of the catalytic core of the spliceosome arrested between the two steps of splicing chemistry (C complex), we investigated the effects of exposing C complex to low concentrations of urea. We find that in the presence of 3M urea C complex separates into at least three sub-complexes. One sub-complex contains the 5'exon, another contains the intron-lariat intermediate, and U2/U5/U6 snRNAs likely comprise a third sub-complex. We purified the intron-lariat intermediate sub-complex and identified several proteins, including U2 snRNP and PRP19 complex (NTC) components. The data from our study indicate that U2 snRNP proteins in C complex are more stably associated with the lariat-intron intermediate than the U2 snRNA. The results also suggest a set of candidate proteins that hold the lariat-intron intermediate together in C complex. This information is critical for further interpreting the complex architecture of the mammalian spliceosome.

Oxazole-bridged combretastatin A-4 analogues bind to tubulin and exert anti-vascular and anti-angiogenic effects. When linked to Ru(η(6)-arene) complex fragments, conjugates with additional cytotoxic activity result which can ruthenate bionucleophiles such as DNA and proteins. For instance, the Ru(II)(p-cymene)(isonicotinate)Cl(2) complex 6a of the known 4-(3,4,5-trimethoxyphenyl)-5-(3-hydroxy-4-methoxyphenyl)-oxazole 4a was far more active than the latter against cells of the p53-competent wild-type form of HCT-116 colon carcinoma at low 0.01 μM concentrations. A fast reaction of 6a with nucleophilic N-acetyl-L-cysteine was observed in NMR studies. The Ru(arene) complexes 6a-c were also more efficacious against combretastatin-refractory p53(+) cells of human HT-29 colon carcinoma when compared to their parent 4-(3,4-dimethoxy-5-methoxy/halo-phenyl)-5-(3-hydroxy-4-methoxyphenyl)-oxazoles 4a-c. These cells are rich in ABC-transporters which are responsible for their multi-drug resistance and for which conjugates 6 are less good substrates than the phenols 4. Unlike 4a, its complex 6a also diminished the motility of human 518A2 melanoma cells in a wound-healing assay which is indicative of anti-metastatic activity in solid tumors. Overall, the Ru(arene) complex conjugates 6 broaden the anti-tumoral spectrum of the combretastatin A-4 analogues 4 considerably., (Copyright © 2010 Elsevier Masson SAS. All rights reserved.)

New combretastatin A analogues featuring oxazole or N-methylimidazole bridged Z-alkenes and halo- or amino-substituted A-rings were tested against various cancer cell lines and in testicular germ cell tumor xenografts in mice. Imidazoles with 3-halo-4,5-dimethoxy substituted A-rings and 3-amino-4-methoxy substituted B-rings (7b and 8b) were efficacious at nanomolar concentrations against cells of combretastatin A refractory HT-29 colon carcinoma, multidrug-resistant MCF-7/Topo breast carcinoma, and cisplatin-resistant 1411HP testicular germ cell tumor. They induced apoptosis and inhibited tubulin polymerization. While well tolerated by mice at high doses, these imidazoles initiated extensive intratumoral hemorrhage and regressions of highly vascularized 1411HP xenografts.

Three new oxazole-bridged combretastatin A analogues with additional functional groups at the B-ring [-SMe, -OH, p-quinone] were tested for antiproliferative activity and specificity on human HL-60 leukemia, 518A2 melanoma, and colon carcinomas HCT-116 (wt)/(p53(-/-)) and HT-29 cells. While all oxazoles, except quinone 8, were efficacious against HCT-116 cells at submicromolar IC(50) values (48 h incubation), only thioanisole 5 achieved this potency in combretastatin-refractory HT-29 cells by significant upregulation of p21(cip1/waf1) associated with an S/G(2) cell-cycle arrest.

Thymoquinone (TQ; 1) is a weak anticancer constituent of black seed oil. Derivatives bearing terpene-terminated 6-alkyl residues were tested in cells of human HL-60 leukemia, 518A2 melanoma, multidrug-resistant KB-V1/Vbl cervix, and MCF-7/Topo breast carcinomas, as well as in non-malignant human foreskin fibroblasts. Derivatives with a short four-atom spacer between quinone and cyclic monoterpene moieties were more antiproliferative than analogues with longer spacers. 6-(Menthoxybutyryl)thymoquinone (3a) exhibited single-digit micromolar IC(50) (72 h) values in all four cell lines. It was seven times more active than TQ (1) in 518A2 melanoma cells and four times in KB-V1/Vbl cervix carcinoma cells, while only half as toxic in the fibroblasts. Compound 3a was also not a substrate for the P-gp and BCRP drug transporters of the resistant cancer cells. The caryophyllyl and germacryl conjugates 3e and 3f specifically inhibited the growth of the resistant MCF-7 breast carcinoma cells. Conjugation of TQ with the triterpene betulinic acid via the OH group as in 3g led to a loss in activity, while conjugation via the carboxylic acid afforded compound 4 with nanomolar IC(50) (72 h) activity against HL-60 cells. All anticancer-active derivatives of TQ (1) induced apoptosis associated with DNA laddering, a decrease in mitochondrial membrane potential and a slight increase in reactive oxygen species.

Progressive respiratory failure due to Pseudomonas aeruginosa is the leading cause of morbidity and mortality in patients with cystic fibrosis. The pulmonary delivery of antimicrobial agents provides high concentrations of drug directly to the site of infection and attains pharmacokinetic-pharmacodynamic indices exceeding those which can be achieved with systemic dosing. MP-376 is a new formulation of levofloxacin that enables the safe aerosol delivery of high concentrations of drug to pulmonary tissues. In vivo studies were conducted to demonstrate the efficacy of MP-376 in models of mouse pulmonary infection. The superiority of aerosol dosing over systemic dosing was demonstrated in models of both acute and chronic lung infection. In a model of acute lung infection, aerosol treatment with MP-376 once or twice daily reduced the lung bacterial load to a greater extent than aerosol tobramycin or aztreonam did when they were administered at similar or higher doses. The bacterial killing by aerosol MP-376 observed in the lung in the model of acute pulmonary infection translated to improved survival (P < 0.05). In a model of chronic pulmonary infection, aerosol MP-376 had antimicrobial effects superior to those of aztreonam (P < 0.05) and effects similar to those of tobramycin (P > 0.05). In summary, these data show that aerosol MP-376 has in vivo activity when it is used to treat acute and chronic lung infections caused by P. aeruginosa.

The unfavorable therapeutic index of the fungal cytotoxin illudin M was to be improved by covalent attachment of the redox modulator and phenyl isobiostere ferrocene. Esters of illudin M with ferrocenoic and 1,1'-ferrocenedioic acid were prepared, structurally characterised (X-ray), and tested for cytotoxicity [MTT assay, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide], induction of apoptosis (TUNEL assay; western blotting for caspase-9), and tumor specificity in cells of human HL-60 leukemia, human 518A2 melanoma, and in nonmalignant human foreskin fibroblasts. The diester of illudin M with 1,1'-ferrocenedioic acid was distinctly more antiproliferative and apoptosis inducing in the melanoma cells [half maximal inhibitory concentration, IC50(48 h) = 0.4+/-0.1 micromol/l] than in the HL-60 cells [IC50(48 h) = 3.0+/-1.6 micromol/l] and in the nonmalignant fibroblasts [IC50(48 h) = 3.7+/-1.9 micromol/l]. This corresponds to a doubling of the therapeutic index with respect to illudin M. The monoester of illudin M with ferrocenoic acid was nine times less efficacious in the cancer cells, when compared with the diester. In conclusion, the ferrocene diminishes the general toxicity of the illudin M moiety and increases its cell line specificity. The bis(illudinyl M) 1,1'-ferrocenedioate presumably operates by a synergistic, two-pronged attack on its molecular targets.

4-Acylhydrazones and 6-alkyl derivatives of thymoquinone (TQ) were tested for growth inhibition of human HL-60 leukemia, 518A2 melanoma, KB-V1/Vbl cervix, and MCF-7/Topo breast carcinoma cells. Unsaturated side chains conferred greater activities than equally long saturated chains. The number of C==C bonds was less decisive than chain length. The 6-hencosahexaenyl conjugate 3 e was most active in all resistant tumor cells, with IC(50) (72 h) values as low as 30 nM in MCF-7/Topo cells. The conjugates are likely to operate by mechanisms different from that of TQ. For instance, 3 e induced distinct caspase-independent apoptosis in HL-60 and 518A2 cells concomitant with a loss of mitochondrial membrane potential and a subsequent rise in the levels of reactive oxygen species.

Mitochondrial pre-messenger RNAs in kinetoplastid protozoa are substrates of uridylate-specific RNA editing. RNA editing converts non-functional pre-mRNAs into translatable molecules and can generate protein diversity by alternative editing. Although several editing complexes have been described, their structure and relationship is unknown. Here, we report the isolation of functionally active RNA editing complexes by a multistep purification procedure. We show that the endogenous isolates contain two subpopulations of approximately 20S and approximately 35-40S and present the three-dimensional structures of both complexes by electron microscopy. The approximately 35-40S complexes consist of a platform density packed against a semispherical element. The approximately 20S complexes are composed of two subdomains connected by an interface. The two particles are structurally related, and we show that RNA binding is a main determinant for the interconversion of the two complexes. The approximately 20S editosomes contain an RNA-binding site, which binds gRNA, pre-mRNA and gRNA/pre-mRNA hybrid molecules with nanomolar affinity. Variability analysis indicates that subsets of complexes lack or possess additional domains, suggesting binding sites for components. Together, a picture of the RNA editing machinery is provided.

The UDP-glucuronosyltransferase (UGT) 1A genes in humans have been shown to be differentially regulated in a tissue-specific fashion. Transgenic mice carrying the human UGT1 locus (Tg-UGT1) were recently created, demonstrating that expression of the nine UGT1A genes closely resembles the patterns of expression observed in human tissues. In the present study, UGT1A1, UGT1A3, UGT1A4, and UGT1A6 have been identified as targets of the peroxisome proliferator-activated receptor (PPAR) alpha in human hepatocytes and Tg-UGT1 mice. Oral administration of the PPARalpha agonist 4-chloro-6-(2,3-xylidino)-2-pyrimidinylthioacetic acid (pirinixic acid, WY-14643) to Tg-UGT1 mice led to induction of these proteins in either the liver, gastrointestinal tract, or kidney. The levels of induced UGT1A3 gene transcripts in liver and UGT1A4 protein in small intestine correlated with induced lamotrigine glucuronidation activity in these tissues. With UGT1A3 previously identified as the major human enzyme involved in human C24-glucuronidation of lithocholic acid (LCA), the dramatic induction of liver UGT1A3 RNA in Tg-UGT1 mice was consistent with the formation of LCA-24G in plasma. Furthermore, PPAR-responsive elements (PPREs) were identified flanking the UGT1A1, UGT1A3, and UGT1A6 genes by a combination of site-directed mutagenesis, specific binding to PPARalpha and retinoic acid X receptor alpha, and functional response of the concatenated PPREs in HepG2 cells overexpressing PPARalpha. In conclusion, these results suggest that oral fibrate treatment in humans will induce the UGT1A family of proteins in the gastrointestinal tract and liver, influencing bile acid glucuronidation and first-pass metabolism of other drugs that are taken concurrently with hypolipidemic therapy.

Morinda citrifolia (noni) is known to contain genotoxic anthraquinones in the roots. Because of the widespread use of noni juice, the possible genotoxic risk was examined through a battery of short-term tests. Noni juice was also chemically analyzed for the possible presence of anthraquinones. Noni juice extract in the Salmonella microsome assay showed a slight mutagenic effect in strain TA1537, due to the presence of flavonoids. No mutagenicity was observed in the mammalian mutagenicity test with V79 Chinese hamster fibroblasts. Rats treated with a noni juice concentrate did not show DNA repair synthesis (UDS) in primary rat hepatocytes, nor could DNA adducts or DNA strand breaks be observed. HPLC analysis of noni juice for anthraquinones was negative, with a sensitivity of <1 ppm. In summary, chemical analysis and genotoxicity tests reveal that noni juice does not have a genotoxic potential and that genotoxic anthraquinones do not exist in noni juice.

Glucuronidation, an important bile acid detoxification pathway, is catalyzed by enzymes belonging to the UDP-glucuronosyltransferase (UGT) family. Among UGT enzymes, UGT1A3 is considered the major human enzyme for the hepatic C24-glucuronidation of the primary chenodeoxycholic (CDCA) and secondary lithocholic (LCA) bile acids. We identify UGT1A3 as a positively regulated target gene of the oxysterol-activated nuclear receptor liver X-receptor alpha (LXRalpha). In human hepatic cells and human UGT1A transgenic mice, LXRalpha activators induce UGT1A3 mRNA levels and the formation of CDCA-24glucuronide (24G) and LCA-24G. Furthermore, a functional LXR response element (LXRE) was identified in the UGT1A3 promoter by site-directed mutagenesis, electrophoretic mobility shift assays and chromatin immunoprecipitation experiment. In addition, LXRalpha is found to interact with the SRC-1alpha and NCoR cofactors to regulate the UGT1A3 gene, but not with PGC-1beta. In conclusion, these observations establish LXRalpha as a crucial regulator of bile acid glucuronidation in humans and suggest that accumulation of oxysterols in hepatocytes during cholestasis favors bile acid detoxification as glucuronide conjugates. LXR agonists may be useful for stimulating both bile acid detoxification and cholesterol removal in cholestatic or hypercholesterolemic patients, respectively.

The human UDP-glucuronosyltransferase 1 (UGT1) locus spans nearly 200 kb on chromosome 2 and encodes nine UGT1A proteins that play a prominent role in drug and xenobiotic metabolism. Transgenic UGT1 (Tg-UGT1) mice have been created, and it has been demonstrated that tissue-specific and xenobiotic receptor control of the UGT1A genes is influenced through circulating humoral factors. In Tg-UGT1 mice, the UGT1A proteins are differentially expressed in the liver and gastrointestinal tract. Gene expression profiles confirmed that all of the UGT1A genes can be targeted for regulation by the pregnane X receptor activator pregnenolone-16alpha-carbonitrile (PCN) or the Ah receptor ligand 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). In addition, the selective induction of glucuronidation activity toward lamotrigine, ethinyl estradiol, chenodeoxycholic acid, and lithocholic acid by either PCN or TCDD in small intestine from Tg-UGT1 mice corresponded to expression of the locus in this tissue. Induction of UGT1A1 by PCN and TCDD is believed to be highly dependent upon glucocorticoids, because submicromolar concentrations of dexamethasone actively promote PCN and TCDD induction of UGT1A1 in Tg-UGT1 primary hepatocytes. The role of hormonal control of the UGT1 locus was further verified in pregnant and nursing Tg-UGT1 mice. In maternal 14-day post-conception Tg-UGT1mice, liver UGT1A1, UGT1A4, and UGT1A6 were induced, with the levels returning to near normal by birth. However, maternal liver UGT1A4 and UGT1A6 were dramatically elevated and maintained after birth, indicating that these proteins may play a critical role in maternal metabolism during lactation. With expression of the UGT1 locus confirmed in a variety of mouse tissues, these results suggested that the Tg-UGT1 mice will be a useful model to examine the regulatory and functional properties of human glucuronidation.

To establish the influence of prolonged denervation on the recovery of a motor nerve, the rat facial nerve was transected and denervated for 0 to 224 days. Then, the freshly transected hypoglossal nerve was sutured to the predegenerated facial nerve (hypoglossal-facial nerve anastomosis, HFA). Using this nerve cross-anastomosis paradigm we analyzed the nerve regeneration and muscle reinnervation 7 to 112 days post-suture operation (DPSO). After HRP injection into the whiskerpad 931+/-27 hypoglossal neurons were labeled at 112 DPSO after immediate HFA. Following 14 to 112 days denervation the number of labeled neurons increased to 138% (14 days delay), 154% (56 days), and 145% (112 days). In contrast, the reinnervation was poorer after 7 days denervation with the number of neurons increasing to 84%, and after long-term denervation of 224 days the number of neurons increased to 81%. The increase in amplitude of evoked electromyography wave after nerve suture correlated with the number of labeled neurons. After immediate HFA each regenerated motoneuron established on average 5.1 myelinated sprouts at 112 DPSO. The number of sprouts remained constant after delayed suture of 14 to 112 days, whereas the slower reinnervation after 7 or 224 days delay was accompanied by a massive sprouting of 9.1 or 8.1, respectively, sprouts per neuron. The muscles showed recovery after any denervation time. The muscle cross-sectional area continuously decreased with longer denervation time. This decrease was only significant after 224 days denervation (67% of the normal value). We conclude that motor nerve reconstruction achieves better functional results after a definite period of denervation when using a nerve cross-anastomosis paradigm., (Copyright 2000 Academic Press.)