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Nanobodies are emerging as critical tools for drug design. Several have been recently created to serve as inhibitors of severe acute respiratory syndrome coronavirus s (SARS-CoV-2) entry in the host cell by targeting surface-exposed spike protein. Here we have established a pipeline that instead targets highly conserved viral proteins made only after viral entry into the host cell when the SARS-CoV-2 RNA-based genome is translated. As proof of principle, we designed nanobodies against the SARS-CoV-2 non-structural protein (Nsp)9, which is required for viral genome replication. One of these anti-Nsp9 nanobodies, 2NSP23, previously characterized using immunoassays and nuclear magnetic resonance spectroscopy for epitope mapping, was expressed and found to block SARS-CoV-2 replication specifically. We next encapsulated 2NSP23 nanobody into lipid nanoparticles (LNPs) as mRNA. We show that this nanobody, hereby referred to as LNP-mRNA-2NSP23, is internalized and translated in cells and suppresses multiple SARS-CoV-2 variants, as seen by qPCR and RNA deep sequencing. These results are corroborated in three-dimensional reconstituted human epithelium kept at air-liquid interface to mimic the outer surface of lung tissue. These observations indicate that LNP-mRNA-2NSP23 is internalized and, after translation, it inhibits viral replication by targeting Nsp9 in living cells. We speculate that LNP-mRNA-2NSP23 may be translated into an innovative strategy to generate novel antiviral drugs highly efficient across coronaviruses., Competing Interests: P.P., G.E., H.T.H., and S.C.D. are part of a US patent filed by New York University in Abu Dhabi jointly with ISAR Biosciences., (© 2024 The Author(s).)

The CRISPR/Cas9 system has emerged as a promising platform for gene editing; however, the lack of an efficient and safe delivery system to introduce it into cells continues to hinder clinical translation. Here, we report a rationally designed gene-editing nanoparticle (NP) formulation for brain applications: an sgRNA:Cas9 ribonucleoprotein complex is immobilized on the NP surface by oligonucleotides that are complementary to the sgRNA. Irradiation of the formulation with a near-infrared (NIR) laser generates heat in the NP, leading to the release of the ribonucleoprotein complex. The gene-editing potential of the formulation was demonstrated in vitro at the single-cell level. The safety and gene editing of the formulation were also demonstrated in the brains of reporter mice, specifically in the subventricular zone after intracerebral administration and in the olfactory bulb after intranasal administration. The formulation presented here offers a new strategy for the spatially controlled delivery of the CRISPR system to the brain., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The development of neurodegenerative diseases is associated with cerebral inflammation, which activates resident immune cells of the central nervous system (CNS), namely microglial cells that show an up-regulation of the cannabinoid subtype 2 receptor (CB 2 R) expression. Therefore our work aimed to design and synthesize a radiotracer for the detection of CB 2 R expression by positron emission tomography (PET) allowing an early diagnosis of neurodegenerative diseases. For the development of such a PET tracer, N-alkyl-substituted indole-3-yl-tetramethylcyclopropylketones served as lead structures due to their high CB 2 R potency and selectivity, allowing radiolabeling on the N-alkyl chain. To this end, eight novel fluorinated N-alkyl-indole-3-yl-tetramethylcyclopropylketones were synthesized, investigated in radioligand binding studies, and structure-activity relationships were evaluated. The most promising candidate was (1-(4-fluoropropyl)-1H-indole-3-yl)(2,2,3,3-tetramethyl-cyclopropyl)methanone (K i : 7.88 nM at the CB 2 R, 3430 nM at cannabinoid subtype 1 receptor (CB 1 R)). A precursor was synthesized, radiofluorinated with no-carrier-added [ 18 F]F - by nucleophilic substitution of a tosyl group, and the resulting PET ligand was purified, all being performed on a fully automated synthesis module. The tracer was produced in 34 ± 6% radiochemical yield within 2 h and with molar activities of up to 1500 GBq/μmol. A first preclinical evaluation was carried out including determination of logP, metabolic stability by liver microsomes, and autoradiography. The novel PET tracer for imaging CB 2 R showed promising results warranting subsequent clinical evaluation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier Masson SAS.)

Despite major treatment advances in recent years, patients with multiple myeloma inevitably relapse. The RNA polymerase II complex has been identified as a promising therapeutic target in both proliferating and dormant cancer cells. Alpha-amanitin, a toxin so far without clinical application due to high liver toxicity, specifically inhibits this complex. Here, we describe the development of HDP-101, an anti-B-cell maturation antigen (BCMA) antibody conjugated with an amanitin derivative. HDP-101 displayed high efficacy against both proliferating and resting myeloma cells in vitro , sparing BCMA-negative cells. In subcutaneous and disseminated murine xenograft models, HDP-101 induced tumor regression at low doses, including durable complete remissions after a single intravenous dose. In cynomolgus monkeys, HDP-101 was well tolerated with a promising therapeutic index. In conclusion, HDP-101 safely and selectively delivers amanitin to myeloma cells and provides a novel therapeutic approach to overcome drug resistance in this disease., (©2020 American Association for Cancer Research.)

A non-internalizing αvβ3 integrin ligand was conjugated to the anticancer drug MMAE through a β-glucuronidase-responsive linker. In the presence of β-glucuronidase, only the conjugate bearing a PEG4 spacer inhibited the proliferation of integrin-expressing cancer cells at low nanomolar concentrations, indicating important structural requirements for the efficacy of these therapeutics.

Breast cancer is the most common cancer in women worldwide. The tumor microenvironment contributes to tumor progression by inducing cell dissemination from the primary tumor and metastasis. TGFβ signaling is involved in breast cancer progression and is specifically elevated during metastatic transformation in aggressive breast cancer. In this study, we performed genomewide correlation analysis of TGFBR2 expression in a panel of 51 breast cancer cell lines and identified that MET is coregulated with TGFBR2. This correlation was confirmed at the protein level in breast cancer cell lines and human tumor tissues. Flow cytometric analysis of luminal and basal-like breast cancer cell lines and examination of 801 tumor specimens from a prospective cohort of breast cancer patients using reverse phase protein arrays revealed that expression of TGFBR2 and MET is increased in basal-like breast cancer cell lines, as well as in triple-negative breast cancer tumor tissues, compared to other subtypes. Using real-time cell analysis technology, we demonstrated that TGFβ1 triggered hepatocyte growth factor (HGF)-induced and MET-dependent migration in vitro. Bioinformatic analysis predicted that TGFβ1 induces expression of C-ets-1 as a candidate transcription factor regulating MET expression. Indeed, TGFβ1-induced expression of ETS1 and breast cancer cell migration was blocked by knockdown of ETS1. Further, we identified that MET is a direct target of miR-128-3p and that this miRNA is negatively regulated by TGFβ1. Overexpression of miR-128-3p reduced MET expression and abrogated HGF-induced cell migration of invasive breast cancer cells. In conclusion, we have identified that TGFβ1 regulates HGF-induced and MET-mediated cell migration, through positive regulation of C-ets-1 and negative regulation of miR-128-3p expression in basal-like breast cancer cell lines and in triple-negative breast cancer tissue., (© 2018 The Authors. Published by FEBS Press and John Wiley & Sons Ltd.)

Aggressive breast cancer is associated with poor patient outcome and characterized by the development of tumor cell variants that are able to escape from control of the immune system or are resistant to targeted therapies. The complex molecular mechanisms leading to immune escape and therapy resistance are incompletely understood. We have previously shown that high miR-519a-3p levels are associated with poor survival in breast cancer. Here, we demonstrate that miR-519a-3p confers resistance to apoptosis induced by TRAIL, FasL and granzyme B/perforin by interfering with apoptosis signaling in breast cancer cells. MiR-519a-3p diminished the expression of its direct target genes for TRAIL-R2 (TNFRSF10B) and for caspase-8 (CASP8) and its indirect target gene for caspase-7 (CASP7), resulting in reduced sensitivity and tumor cell apoptosis in response to apoptotic stimuli. Furthermore, miR-519a-3p impaired tumor cell killing by natural killer (NK) cells via downregulation of the NKG2D ligands ULBP2 and MICA on the surface of tumor cells that are crucial for the recognition of these tumor cells by NK cells. We determined that miR-519a-3p was overexpressed in more aggressive mutant TP53 breast cancer that was associated with poor survival. Furthermore, low levels of TRAIL-R2, caspase-7 and caspase-8 correlated with poor survival, suggesting that the inhibitory effect of miR-519a-3p on TRAIL-R2 and caspases may have direct clinical relevance in lowering patient's prognosis. In conclusion, we demonstrate that miR-519a-3p is a critical factor in mediating resistance toward cancer cell apoptosis and impairing tumor cell recognition by NK cells. This joint regulation of apoptosis and immune cell recognition through miR-519a-3p supports the hypothesis that miRNAs are key regulators of cancer cell fate, facilitating cancer progression and evasion from immunosurveillance at multiple and interconnected levels.

The tumor microenvironment (TME) has an impact on breast cancer progression by creating a pro-inflammatory milieu within the tumor. However, little is known about the roles of miRNAs in cells of the TME during this process. We identified six putative oncomiRs in a breast cancer dataset, all strongly correlating with poor overall patient survival. Out of the six candidates, miR-1246 was upregulated in aggressive breast cancer subtypes and expressed at highest levels in mesenchymal stem/stroma cells (MSCs). Functionally, miR-1246 led to a p65-dependent increase in transcription and release of pro-inflammatory mediators IL-6, CCL2 and CCL5 in MSCs, and increased NF-κB activity. The pro-inflammatory phenotype of miR-1246 in MSCs was independent of TNFα stimulations and mediated by direct targeting of the tumor-suppressors PRKAR1A and PPP2CB. In vitro recapitulation of the TME revealed increased Stat3 phosphorylation in breast epithelial (MCF10A) and cancer cells (SK-BR-3, MCF7, T47D) upon incubation with conditioned medium (CM) of MSCs overexpressing miR-1246. Additionally, this stimulation enhanced proliferation of MCF10A cells, increased migration of MDA-MB-231 cells and induced attraction of THP-1 monocytic cells. Our data shows that miR-1246 acts as both key-enhancer of pro-inflammatory responses in MSCs and putative oncomiR in breast cancer, suggesting its influence on cancer-related inflammation and breast cancer progression.

Objective: After horizontal supraglottic partial laryngectomy, patients have an increased risk of dysphagia as they are not able to close the laryngeal entrance during swallowing, especially if the surgical defect of the tongue base has increased. There is no investigation that studies risk factors for impaired swallow function, or that predicts postoperative swallow outcomes based on radiologically determined tumor dimensions. The present study investigated the impact of the tongue base tumor extension (determined by CT scan in patients undergoing partial laryngectomy) on the recovery rate of swallow function., Methods: The retrospective study in a tertiary hospital between 2000 and 2015 included all patients who underwent open horizontal supraglottic partial laryngectomy due to oropharyngeal cancer of the tongue base, or supraglottic laryngeal cancer with tongue base infiltration. All clinicopathological data were collected. The dimension of tongue base infiltration was measured using CT scan. Swallow function was recorded by Fiberoptic Endoscopic Evaluation of Swallowing and determined by evaluating both the duration until nasogastric tube removal and changing of the cuffed tracheostomy tube for an uncuffed speech cannula., Results: The study included 26 patients (44-76 years, median 59 years). The clinical tumor (cT) classification included cT2 and cT3, while the pathologic tumor (pT) classification included pT2 and pT3 in 90% and pT1 and pT4 in 10% respectively. The duration until using the speech cannula was not associated with clinicopathological data, including the investigated radiologic tumor dimensions (biggest tumor diameter, tongue base infiltration depth, width, height, area and volume). The duration until nasogastric tube removal was significantly associated with the tongue base infiltration width (p=0.012), height (p=0.026) and area (p<0.0001). The patients were divided into two groups according to the median tongue base infiltration area estimated as 6.20cm(2). In patients <6.20cm(2), 50% of the nasogastric tubes were removed after 4 days (95% CI 0-8.6 days) and in patients ≥6.20cm(2), 50% were removed after 22 days (95% CI 6.8-37.2 days; p<0.0001)., Conclusion: The postoperative swallow function after open horizontal supraglottic partial laryngectomy depends on the tumor extension of the tongue base. The tongue base infiltration area is a useful tool for surgical planning as it can be used to predict postoperative swallow function. In foreseeably permanent dysphagia, as well as permanent and necessary tracheotomy tube cuffs after organ-preserving surgery, alternative therapy methods should be particularly preferred as the primary chemoradiation., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Background: The bacterial CRISPR system is fast becoming the most popular genetic and epigenetic engineering tool due to its universal applicability and adaptability. The desire to deploy CRISPR-based methods in a large variety of species and contexts has created an urgent need for the development of easy, time- and cost-effective methods enabling large-scale screening approaches., Results: Here we describe CORALINA (comprehensive gRNA library generation through controlled nuclease activity), a method for the generation of comprehensive gRNA libraries for CRISPR-based screens. CORALINA gRNA libraries can be derived from any source of DNA without the need of complex oligonucleotide synthesis. We show the utility of CORALINA for human and mouse genomic DNA, its reproducibility in covering the most relevant genomic features including regulatory, coding and non-coding sequences and confirm the functionality of CORALINA generated gRNAs., Conclusions: The simplicity and cost-effectiveness make CORALINA suitable for any experimental system. The unprecedented sequence complexities obtainable with CORALINA libraries are a necessary pre-requisite for less biased large scale genomic and epigenomic screens.

Background: In Germany, testicular cancer accounts for about 1-2% of all malignant tumours. Although, therefore, this is a rare tumour, it assumes an exceptional position among malignant tumours in several respects. In male patients aged 20-35 years it is the most common tumour, which directly affects the family and life planning of young men, a matter of prime importance at this age. Another aspect of testicular cancer is its excellent prognosis since the introduction of platinum-based chemotherapy into the armamentarium of testicular cancer therapy. Therefore, therapeutic innovations increasingly focus on reducing the radicality of treatment, even more so since this therapy, in addition to acute toxicity, can cause severe long-term consequences up to and including secondary malignancies., Objectives: This article gives an overview of the present therapeutic standard of stage I testicular cancer treatment., Material and Methods: Selective PubMed research Results and Discussion: Besides potential implications for organ-sparing surgery, the article elucidates the benefits of a risk-adapted therapeutic approach and indications for a surveillance strategy for patients with localised testicular cancer., (© Georg Thieme Verlag KG Stuttgart · New York.)

Nuclear Factor kappa B (NF-κB) signaling is frequently deregulated in a variety of cancers and is constitutively active in estrogen receptor negative (ER-) breast cancer subtypes. These molecular subtypes of breast cancer are associated with poor overall survival. We focused on mechanisms of NF-κB regulation by microRNAs (miRNAs), which regulate eukaryotic gene expression at the post-transcriptional level. In a previous genome-wide miRNA screen, we had identified miR-30c-2-3p as one of the strongest negative regulators of NF-κB signaling. Here we have uncovered the underlying molecular mechanisms and its consequences in breast cancer. In vitro results show that miR-30c-2-3p directly targets both TNFRSF1A-associated via death domain (TRADD), an adaptor protein of the TNFR/NF-κB signaling pathway, and the cell cycle protein Cyclin E1 (CCNE1). Ectopic expression of miR-30c-2-3p downregulated essential cytokines IL8, IL6, CXCL1, and reduced cell proliferation as well as invasion in MDA-MB-231 breast cancer cells. RNA interference (RNAi) induced silencing of TRADD phenocopied the effects on invasion and cytokine expression caused by miR-30c-2-3p, while inhibition of CCNE1 phenocopied the effects on cell proliferation. We further confirmed the tumor suppressive role of this miRNA using a dataset of 781 breast tumors, where higher expression was associated with better survival in breast cancer patients. In summary we have elucidated the mechanism by which miR-30c-2-3p negatively regulates NF-κB signaling and cell cycle progression in breast cancer., (Copyright © 2015 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.)

Central skull base osteomyelitis (SBO) is a life-threatening disease originating from ear and from sinonasal infections. The intention of this study was to evaluate contemporary trends in etiology, diagnosis, management, and outcome of SBO and to draw the clinician's attention on this probably underestimated disease. Over a 6-year period we performed this systematic study in an academic quaternary medical care and skull base center including 20 patients (mean age 63.7 years) with central SBO, which is one of the largest series from a single center. In contrast to previous studies we explicitly excluded infections limited to malignant external otitis only but did not restrict central SBO to conditions unrelated to aural pathology. Fifteen patients had otogenic and five sinugenic SBO; four patients had fungal or mixed fungal infections. Pre-existing illnesses altering bone vascularization were detected in 70 % of the patients and had a negative effect on the improvement of cranial nerve palsies that were found in 14 patients. In relation, patients with otogenic SBO more often had local and systemic predisposing factors. Contrary to previous studies 16 patients (80 %) underwent surgical therapy and none of our patients died. A meta-analysis of five recent studies was done and compared with our own data and two previous meta-analyses. The present study highlights several important aspects with major implications for diagnosis and treatment of SBO that have not been adequately addressed as yet. In contrast to the restrictive attitude towards surgery in literature we recommend early and radical operative treatment to reduce its mortality.

Introduction: In 2006, the American Academy of Pediatrics published a policy statement recommending routine developmental screening for all children. Most clinicians at that time were using informal methods to monitor child development., Methods: Outreach to Wisconsin primary care clinicians designed to promote use of validated developmental screening tools began in 2006. A survey of 157 Wisconsin primary care clinicians was conducted in late 2012 to assess routine use of developmental and autism-specific tools., Results: As compared with a similar survey conducted in 2007, where only 25% of clinicians reported use of a validated developmental screening tool, over 55% of clinicians in this survey reported routine use of validated developmental and autism-specific screening tools within well-child care., Conclusion: Outreach to clinicians and their care teams, in conjunction with policy statements from national professional organizations and supporting evidence, can contribute to quality improvement in well-child care delivery.

Expression of L1 cell adhesion molecule (L1CAM) occurs frequently in human cancers and is associated with poor prognosis in cancers such as ovarian, endometrial, breast, renal cell carcinoma and pancreatic ductal adenocarcinoma. L1CAM promotes cell motility, invasion, chemoresistance and metastasis formation. Elucidating genetic processes involved in the expression of L1CAM in cancers is of considerable importance. Transcription factors such as SLUG, β-catenin/TCF-LEF, PAX8 and VHL have been implicated in the re-activation of L1CAM in various types of cancers. There is increasing evidence that micro-RNAs can also have strong effects on gene expression. Here we have identified miR-21-3p as a positive regulator of L1CAM expression. Over-expression of miR-21-3p (miR-21*) but not the complementary sequence miR-21-5p (miR-21) could strongly augment L1CAM expression in renal, endometrial and ovarian carcinoma derived cell lines by an unknown mechanism involving transcriptional activation of the L1CAM gene. In patient cohorts from renal, endometrial and ovarian cancers we observed a strong positive correlation of L1CAM and miR-21-3p expressions. Although L1CAM alone was a reliable marker for overall and disease free survival, the combination of L1CAM and miR-21-3p expressions strongly enhanced the predictive power. Our findings shed new light on the complex regulation of L1CAM in cancers and advocate the use of L1CAM/miR-21-3p for diagnostic application., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Purpose: Small molecule inhibitors of the mitogen-activated protein kinase (MAPK) pathway, such as sorafenib, represent novel treatment options for advanced hepatocellular carcinoma. The aim of our study was to identify downstream targets as biomarker candidates that are directly linked to the oncogenic MAPK pathway in hepatocellular carcinoma and correlate with inhibition of this pathway by multikinase inhibitors., Experimental Design: Hepatocellular carcinoma cell lines and fresh tumor and tumor-free liver tissues from patients with hepatocellular carcinoma were incubated with different BRaf or MEK inhibitors and analyzed for kinase phosphorylation, proliferation, induction of apoptosis, and chemokine secretion., Results: Hepatocellular carcinoma cell lines responded differentially to these inhibitors in a dose-dependent manner, even those targeting the same kinase. Sorafenib inhibited both MEK1 and ERK1/2 phosphorylation at high but increased signaling at low concentrations. Similarly, PLX4720 increased MEK/ERK signaling independently from mutations in BRaf or NRas. MEK inhibitors decreased ERK1/2 phosphorylation in a dose-dependent manner. These signaling characteristics correlated with inhibition of proliferation, induction of apoptosis, and chemokine secretion. Fresh tissues derived from patients diagnosed with primary hepatocellular carcinoma responded to these inhibitors with changes in their microenvironment following the patterns observed in hepatocellular carcinoma cells., Conclusions: Oncogenic signaling of the MAPK pathway influences hepatocellular carcinoma sensitivity to treatment with BRaf and MEK inhibitors about cell fate independently from mutations in BRaf and NRas. MAPK inhibitors have a strong impact on chemokine secretion as a consequence of interference with oncogenic signaling. Therefore, novel biomarker candidates associated with the hepatocellular carcinoma microenvironment may be developed for prediction and monitoring of treatment response to small molecule inhibitors., (©2014 AACR.)

L1CAM promotes cell motility, invasion and metastasis formation in various human cancers and can be considered as a driver of tumor progression. Knowledge about genetic processes leading to the presence of L1CAM in cancers is of considerable importance. Experimentally, L1CAM expression can be achieved by various means. Over-expression of the transcription factor SLUG or treatment of cells with TGF-β1 can induce or augment L1CAM levels in cancer cells. Likewise, hypomethylation of the L1CAM promoter on the X chromosome correlates with L1CAM expression. However, presently no mechanisms that might control transcriptional activity are known. Here we have identified miR-34a as a suppressor of L1CAM. We observed that L1CAM positive endometrial carcinoma (EC) cell lines HEC1B and SPAC1L lost L1CAM protein and mRNA by treatment with demethylating agents or knock-down of the DNA-methyltransferase-1 (DNMT1). Concomitantly, several miRNAs were up-regulated. Using miRNA profiling, luciferase reporter assays and mutagenesis, we identified miR-34a as a putative binder to the L1CAM-3'UTR. Over-expression of miR-34a in HEC1B cells blocked L1CAM expression and inhibited cell migration. In ECC1 cells (wildtype p53) the activation of p53 caused miR-34a up-regulation and loss of L1CAM expression that was miR-34a dependent. We observed an inverse correlation between L1CAM and miR-34a levels in EC cell lines. In primary tumor sections areas expressing high amounts of L1CAM had less miR-34a expression than those with low L1CAM levels. Our data suggest that miR-34a can regulate L1CAM expression by targeting L1CAM mRNA for degradation. These findings shed new light on the complex regulation of L1CAM in human tumors.

Context: Self-management is important in ensuring good clinical results in kidney transplant recipients. It was unclear whether the current education program at a single kidney transplant center sufficiently prepares recent transplant recipients for the many complex self-management tasks required., Objective: To evaluate the completeness of and the satisfaction with the current inpatient kidney transplant education program and to determine recipients' needs for information in the first months after discharge., Methods: We used a concurrent mixed-methods design, including 31 kidney transplant recipients who were assessed via a semistructured interview (qualitative part) and a questionnaire specifically designed for this study, consisting of 30 Likert-type and open-ended questions (quantitative part)., Results: Kidney transplant patients reported having received extensive information about medication use after transplant surgery (antirejection medication, 93.5%). Information about healthy lifestyle (physical activity and rehabilitation, 54.8%), return to work (54.8%), and emotional coping (25.8%) was considered suboptimal, although most patients expressed a need for such information. Patients indicated a need for more concrete and practical information, not only during their hospital stay, but also in the long term after transplant., Conclusions: This is the first mixed-models approach showing that our education program immediately after transplant focuses on the transfer of factual knowledge, which seems to insufficiently train patients in developing self-management skills. Updates of our program are warranted to overcome the gaps in the information provided, to provide more practical tips, and to repeat education in the long-term after the transplant surgery, tailored to the patients' needs.

Purpose: To evaluate image quality of dose-reduced CT of the paranasal-sinus using an iterative reconstruction technique., Methods: In this study 80 patients (mean age: 46.9±18 years) underwent CT of the paranasalsinus (Siemens Definition, Forchheim, Germany), with either standard settings (A: 120 kV, 60 mAs) reconstructed with conventional filtered back projection (FBP) or with tube current-time product lowering of 20%, 40% and 60% (B: 48 mAs, C: 36 mAs and D: 24 mAs) using iterative reconstruction (n=20 each). Subjective image quality was independently assessed by four blinded observers using a semiquantitative five-point grading scale (1=poor, 5=excellent). Effective dose was calculated from the dose-length product. Mann-Whitney-U-test was used for statistical analysis., Results: Mean effective dose was 0.28±0.03 mSv(A), 0.23±0.02 mSv(B), 0.17±0.02 mSv(C) and 0.11±0.01 mSv(D) resulting in a maximum dose reduction of 60% with iterative reconstruction technique as compared to the standard low-dose CT. Best image quality was observed at 48 mAs (mean 4.8; p<0.05), whereas standard low-dose CT (A) and maximum dose reduced scans (D) showed no significant difference in subjective image quality (mean 4.37 (A) and 4.31 (B); p=0.72). Interobserver agreement was excellent (κ values 0.79-0.93)., Conclusion: As compared to filtered back projection, the iterative reconstruction technique allows for significant dose reduction of up to 60% for paranasal-sinus CT without impairing the diagnostic image quality., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Purpose: To date, no valid imaging modality exists for early response prediction to neoadjuvant radiochemotherapy in carcinoembryonic-antigen-(CEA)-expressing rectal cancers (UICC stages II and III). It is hypothesized that the uptake of an anti-CEA antibody is directly related to the number of viable tumor cells and may be quantified by immuno-positron emission tomography (immuno-PET). Therefore, we evaluated a novel pretargeting system using TF2, a humanized bispecific trivalent monoclonal antibody (mAb), directed against CEA and the IMP-288-peptide, a hapten for binding radiometals for imaging. Uptake and kinetics of the pretargeting system were investigated in vitro prior to and after irradiation., Methods: TF2 was labeled with ¹³¹I and IMP-288 with ¹¹¹InCl₃. The colorectal cancer cell lines HT29, SW480, and T84 with known varying CEA expression were incubated (≤ 72 hours) with ¹³¹I-TF2 or the TF2-¹¹¹In-IMP-288 pretargeting system. Parallel cultures were irradiated with 2-10 Gy high-energy photons. Tracer uptake, proliferation, apoptosis, and CEA-RNA expression of cancer cells were investigated., Results: The uptake of tracers was dependent on CEA expression and cell count of the cell lines (uptake/10⁶ cells: 0.3% in HT29, 1.5% in SW480, and 14% in T84, p < 0.001). The TF2-¹¹¹In-IMP-288 pretargeting system showed a higher uptake after 4 and 72 hours compared to (131)I-TF2 in parallel cultures. Only in one cell line (SW480) an increased apoptosis after irradiation could be detected. Irradiation increased dose dependently both the specific uptake of ¹³¹I-TF2 and of the TF2-¹¹¹In-IMP-288 system (4-fold in HT29 and T84 after 10 Gy (72 hours), p < 0.001). These results were CEA-mRNA independent., Conclusion: This novel pretargeting system allows the quantitative analysis of CEA-expressing colorectal cancer cells and represents a promising tool for evaluation of tumor cell viability after irradiation.