OGDH and Bcl-xL loss causes synthetic lethality in glioblastoma

Glioblastoma (GBM) remains an incurable disease, requiring more effective therapies. Through interrogation of publicly available CRISPR and RNAi library screens, we identified the α-ketoglutarate dehydrogenase (OGDH) gene, which encodes an enzyme that is part of the tricarboxylic acid (TCA) cycle, as essential for GBM growth. Moreover, by combining transcriptome and metabolite screening analyses, we discovered that loss of function of OGDH by the clinically validated drug compound CPI-613 was synthetically lethal with Bcl-xL inhibition (genetically and through the clinically validated BH3 mimetic, ABT263) in patient-derived xenografts as well neurosphere GBM cultures. CPI-613-mediated energy deprivation drove an integrated stress response with an upregulation of the BH3-only domain protein, Noxa, in an ATF4-dependent manner, as demonstrated by genetic loss-of-function experiments. Consistently, silencing of Noxa attenuated cell death induced by CPI-613 in model systems of GBM. In patient-derived xenograft models of GBM in mice, the combination treatment of ABT263 and CPI-613 suppressed tumor growth and extended animal survival more potently than each compound on its own. Therefore, combined inhibition of Bcl-xL along with disruption of the TCA cycle might be a treatment strategy for GBM.

Art engagement and psychological well-being among community-dwelling older adults in Japan: an observational cross-sectional study

OBJECTIVES

Art engagement, which includes individual art activities and museum and gallery visits, potentially contributes to improving psychological well-being. However, there is insufficient evidence of its effects on the older population, and few reports are from Asia, including Japan. This study examined the association between art engagement and psychological well-being among older adults in Japan.

STUDY DESIGN

An observational cross-sectional study design was used.

METHODS

Community-dwelling older adults aged ≥60 years were recruited from the visitors to public facilities (including community centres, sports centres and cultural centres) in Aichi, Japan, in 2022, and completed questionnaires. The psychological well-being assessment included five domains according to Seligman's PERMA framework: Positive emotion, Engagement, Relationship, Meaning and Accomplishment. Regarding art engagement, the frequencies of active art engagement (e.g. activities by individuals and participation in groups, such as music and painting) and receptive art engagement (e.g. visiting museums, galleries and the theatres) were assessed.

RESULTS

A total of 522 participants were included in the analysis (mean age = 74.1 years; 78.0% females). Results from the multivariable linear regression analysis, which adjusted for demographic and socio-economic factors, revealed that higher frequencies of active art engagement were significantly associated with higher scores in all five PERMA domain scores. Higher frequencies of receptive art engagement were significantly associated with higher levels of Positive emotion, Engagement and Meaning domain scores, but were only marginally associated with the Accomplishment domain and were not associated with the Relationships domain.

CONCLUSIONS

This study indicates that art engagement has the potential to enhance psychological well-being among older adults. National and local government strategies to increase accessibility to art and cultural activities for older adults are recommended.

Targeting cellular respiration as a therapeutic strategy in glioblastoma

While glycolysis is abundant in malignancies, mitochondrial metabolism is significant as well. Mitochondria harbor the enzymes relevant for cellular respiration, which is a critical pathway for both regeneration of reduction equivalents and energy production in the form of ATP. The oxidation of NADH₂ and FADH₂ are fundamental since NAD and FAD are the key components of the TCA-cycle that is critical to entertain biosynthesis in cancer cells. The TCA-cycle itself is predominantly fueled through carbons from glucose, glutamine, fatty acids and lactate. Targeting mitochondrial energy metabolism appears feasible through several drug compounds that activate the CLPP protein or interfere with NADH-dehydrogenase, pyruvate-dehydrogenase, enzymes of the TCA-cycle and mitochondrial matrix chaperones. While these compounds have demonstrated anti-cancer effects in vivo, recent research suggests which patients most likely benefit from such treatments. Here, we provide a brief overview of the status quo of targeting mitochondrial energy metabolism in glioblastoma and highlight a novel combination therapy.

Prevalence and genotype distribution of human papillomavirus infections in Beijing, China between 2016 and 2020

BACKGROUND

Certain types of human papillomavirus (HPV) induce long-lasting infections that cause cervical cancer. This study evaluated the prevalence of HPV infections and the distribution of their genotypes among clinic patients and healthy women in Beijing, China.

METHODS

Cervical specimens were collected from 12,100 patients and 1176 subjects who underwent physical examinations at Dongzhimen Hospital, Beijing University of Chinese Medicine, between March 2016 and September 2020. HPV genotyping was performed using commercial kits designed to detect 15 high-risk and 2 low-risk HPV genotypes.

RESULTS

There was a higher overall prevalence of HPV among the clinic patients (21.0%) than among the healthy women (11.9%). The most common HPV genotypes among the patients were: HPV-52 (5.4%), HPV-16 (3.4%), HPV-58 (3.2%), HPV-51 (2.6%), HPV-39 (2.0%), HPV-56 (2.0%), and HPV-66 (2.0%). Among the healthy women: HPV-52 (3.0%), HPV-51 (1.8%), HPV-58 (1.6%), HPV-66 (1.5%), HPV-16 (1.2%), HPV-56 (1.2%), and HPV-18 (1.1%). Multiple HPVs were detected in 29.1% of the gynecological outpatients and in 23.6% of the women receiving physical examinations. The most common pairs of HPV types detected were HPV-52 and HPV-16 in the clinic patients, and HPV-52 and HPV-56 in the healthy women. Age-specific HPV positivity and peak prevalence were observed among the individuals in both groups for women aged less than 25 years and those between 61 and 65 years of age.

CONCLUSIONS

Our results provide current estimates of HPV prevalence and genotypes in the Beijing region. The epidemiological characteristics observed also provide a reference for the development of cervical cancer screening strategies and selection of HPV vaccine antigen targets for this region. A comparison of these HPV prevalence data with those from other regions suggests that regional vaccines may be an important direction for future research.

TMET-38. LOSS OF FUNCTION OF CDK7 IS SYNTHETICALLY LETHAL WITH FATTY ACID OXIDATION INHIBITION IN GLIOBLASTOMA

CDK7 has been identified as a potential drug target for glioblastoma (GBM), a highly lethal primary brain tumor. However, resistance to therapy develops quickly, which may be facilitated by drug-induced reprogramming of metabolism. By combination of a transcriptome and metabolite screening analyses followed by carbon tracing (U-13C-Glucose, U-13C-Glutamine and U-13C-Palmitic acid) and extracellular flux analysis we demonstrated that both genetic and pharmacological (YKL-5-124 and THZ1) CDK7 inhibition elicited substantial metabolic reprogramming. Specifically, CDK7i elicited an increase of oxygen consumption rate fueled by enhanced fatty acid oxidation (FAO) manifested by enhanced labeling of citric acid cycle intermediates from palmitic acid. Consistently, the combination treatment of CDK7i inhibitors with blockers of FAO (etomoxir) or cellular respiration (gamitrinib) exerted substantial synergistic growth inhibition in patient derived xenograft as well as neurosphere GBM cultures, which was mainly driven by a collapse of oxidative energy metabolism. In turn, exogenous administration of adenosine triphosphate partially rescued from the cell death induced by the combination treatment. Moreover, the combination treatment activated intrinsic apoptosis through a reduction of both Mcl-1 and Bcl-xL as demonstrated by rescue experiments. Finally, the combined administration of YKL-5-124 and etomoxir extended overall in an orthotopic patient-derived xenograft model of GBM. In summary, these data support that simultaneous targeting of CDK7 and FAO might be a potential novel therapy against GBM.

TMET-39. INHIBITION OF THE TCA-CYCLE IS SYNTHETICALLY LETHAL WITH LOSS OF FUNCTION OF BCL-XL IN GLIOBLASTOMA

Glioblastoma (GBM) remains an incurable disease, requiring more effective therapies. Through CRISPR and RNAi library screening interrogation we identified several TCA-cycle enzymes as essential for GBM growth. By combining a transcriptome and metabolite screening analyses we discovered that inhibition of the TCA-cycle by the clinically validated drug compound, CPI-613, is synthetically lethal with Bcl-xL loss of function (genetically and through the clinically validated BH3-mimetic, ABT263) in patient-derived xenograft as well neurosphere GBM cultures. Carbon tracing experiments (U-13 C-glucose and U-13 C-glutamine) and extracellular flux analysis showed that CPI-613 interferes with mitochondrial respiration. In turn, CPI-613 mediated energy deprivation drives an integrated stress response with an up-regulation of the BH3-only domain protein, Noxa in an ATF4 dependent manner as demonstrated by genetic loss of function experiments. Consistently, silencing of Noxa rescued from cell death induced by CPI-613 as well as by the combination treatment of ABT263 and CPI-613 in model systems of GBM. In patient-derived xenograft models of GBM in mice, the combination treatment of ABT263 and CPI613 suppressed tumor growth more potently than each compound on its own. Therefore, combined inhibition of Bcl-xL along with interference of the TCA-cycle might be a novel treatment strategy for GBM.

Induction of Synthetic Lethality by Activation of Mitochondrial ClpP and Inhibition of HDAC1/2 in Glioblastoma

PURPOSE

Novel therapeutic targets are critical to unravel for the most common primary brain tumor in adults, glioblastoma (GBM). We have identified a novel synthetic lethal interaction between ClpP activation and HDAC1/2 inhibition that converges on GBM energy metabolism.

EXPERIMENTAL DESIGN

Transcriptome, metabolite, and U-13C-glucose tracing analyses were utilized in patient-derived xenograft (PDX) models of GBM. Orthotopic GBM models were used for in vivo studies.

RESULTS

We showed that activation of the mitochondrial ClpP protease by mutant ClpP (Y118A) or through utilization of second-generation imipridone compounds (ONC206 and ONC212) in combination with genetic interference of HDAC1 and HDAC2 as well as with global (panobinostat) or selective (romidepsin) HDAC inhibitors caused synergistic reduction of viability in GBM model systems, which was mediated by interference with tricarboxylic acid cycle activity and GBM cell respiration. This effect was partially mediated by activation of apoptosis along with activation of caspases regulated chiefly by Bcl-xL and Mcl-1. Knockdown of the ClpP protease or ectopic expression of a ClpP D190A mutant substantially rescued from the inhibition of oxidative energy metabolism as well as from the reduction of cellular viability by ClpP activators and the combination treatment, respectively. Finally, utilizing GBM PDX models, we demonstrated that the combination treatment of HDAC inhibitors and imipridones prolonged host survival more potently than single treatments or vehicle in vivo.

CONCLUSIONS

Collectively, these observations suggest that the efficacy of HDAC inhibitors might be significantly enhanced through ClpP activators in model systems of human GBM.

Methodological Approaches for Assessing Metabolomic Changes in Glioblastomas

Glioblastoma (GBM), a highly malignant primary brain tumor, inevitably leads to death. In the last decade, a variety of novel molecular characteristics of GBMs were unraveled. The identification of the mutation in the IDH1 and less commonly IDH2 gene was surprising and ever since has nurtured research in the field of GBM metabolism. While initially thought that mutated IDH1 were to act as a loss of function mutation it became clear that it conferred the production of an oncometabolite that in turn substantially reprograms GBM metabolism. While mutated IDH1 represents truly the tip of the iceberg, there are numerous other related observations in GBM that are of significant interest to the field, including the notion that oxidative metabolism appears to play a more critical role than believed earlier. Metabolic zoning is another important hallmark of GBM since it was found that the infiltrative margin that drives GBM progression reveals enrichment of fatty acid derivatives. Consistently, fatty acid metabolism appears to be a novel therapeutic target for GBM. How metabolism in GBM intersects is another pivotal issue that appears to be important for its progression and response and resistance to therapies. In this review, we will summarize some of the most relevant findings related to GBM metabolism and cell death and how these observations are influencing the field. We will provide current approaches that are applied in the field to measure metabolomic changes in GBM models, including the detection of unlabeled and labeled metabolites as well as extracellular flux analysis.

TAMI-17. INDUCTION OF SYNTHETIC LETHALITY BY ACTIVATION OF MITOCHONDRIAL CLPP AND INHIBITION OF HDAC1/2 IN GLIOBLASTOMA

Activation of the mitochondrial ClpP protease is an innovative therapeutic concept and the identification of synthetic lethal interactions may foster the development of novel therapies for glioblastoma (GBM). By integration of a transcriptome, metabolite and U-13C-glucose tracing analyses, we showed that activation of the mitochondrial ClpP protease through constitutively active ClpP (Y118A) or utilization of second-generation imipridone compounds (ONC206 and ONC212) in combination with genetic interference of HDAC1 and HDAC2 as well as with global (Panobinostat) and selective (Romidepsin) HDAC inhibitors caused synergistic reduction of viability in established, neuro-sphere and patient-derived xenograft (PDX) cultures of human GBM, which was mediated by interference with tricarboxylic acid cycle activity and GBM cell respiration. Notably, human astrocytes were significantly less susceptible to the combination treatment of HDAC-inhibitors and ClpP activators. The reduction of GBM viability occurred independent of TP53 status and was accompanied by activation of cell death with apoptotic features along with cleavage of caspases regulated chiefly by Bcl-xL and Mcl-1. Importantly, knockdown of the ClpP protease or ectopic expression of a ClpP D190A mutant almost completely rescued from the inhibition of oxidative energy metabolism as well as from the reduction of cellular viability by ClpP activators and the combination treatment, suggesting critical involvement of this protein. Finally, utilizing GBM PDX models, we demonstrated that the combination treatment of HDAC-inhibitors and imipridones reduced tumor growth and prolonged host survival more potently than single treatments or vehicle in vivo. Collectively, these observations suggest that the efficacy of HDAC inhibitors might be significantly enhanced through ClpP activators in model systems of human GBM.

TP7.2.9 Natural orifice surgery in early rectal cancer; is it the way forward?

Aims

Transanal-endoscopic microsurgery (TEMS) for early rectal cancer is an attractive alternative to radical surgery. With proper patient selection, it is possible to achieve acceptable oncological outcomes with fewer complications. We aim to study the outcomes following TEMS for suspicious or proven rectal cancers performed in our unit.

Method

We performed a retrospective analysis of prospectively collected data between May-17 and Oct-20. The patients’ details, tumour specific data, short term outcomes, and recurrences were recorded.

Results

A total of 45 patients with early rectal cancer (M = 29, F = 15) were included in this study. With1 exclusion due to intraoperative rectal perforation, 44 were available for further analysis. Eleven had a diagnosis of cancer at the time of surgery, an additional 11 patients were confirmed on final histology, and 22 were benign. Final histology showed: T1=14, T2=4, T3=3 &Tx=1. The majority (68%) had clear resection margins (R1=3, R2=1, Rx = 3). Twelve patients went on to have further treatment. Seven had resectional surgery (AR = 5, APR=2) for unfavorable histology (2), residual disease (3), or recurrence (2). The other 5(23%) received chemotherapy+/-radiotherapy (unfit/patients’ choice) for unfavorable. Histology (3) or residual disease (2).

Conclusion

With judicious patient selection, it is possible to offer a less invasive option with acceptable oncological and patient related outcomes for suspicious and proven malignant rectal lesions. The majority of patients (84%) were able to avoid radical surgery or stoma, thereby reducing the associated morbidity. Whilst this is a single institution study, we believe with available expertise this could be widely replicated.

SP4.2.6 Colorectal cancer services during COVID-19; an experience of a tertiary centre

Aims

COVID19 has placed unprecedented constraints on healthcare services. Colorectal cancer (CRC) care was one of the many areas predicted to suffer due to these additional pressures. We believe that despite the challenges posed by COVID19, we have continued to deliver a standard of care for elective and emergency CRC resection that compares favorably with the national average.

Method

We conducted an analysis of the elective and emergency CRC resections carried out at a tertiary center over a 10-month period (Feb-Dec 2020). Data was collated from patient, operative, and theatre records and compared to the national average as defined by the 2020 National Bowel Cancer Audit (NBOCA).

Results

A total of 227 patients underwent surgery (189 elective and 38 emergencies), with a median age of 69. Of these, 153 were laparoscopic (67%), 57 open (27%), and 17 robotic (7%). The median length of stay was less than the national average; 5 days for elective surgery (NBOCA: 6) and 8 days for emergencies (NBOCA: 10). Within 30 days, overall unplanned readmissions rate was 6.5% (NBOCA: 11.6%) and return to theatre was 3.2% (NBOCA: 8.4%). Elective surgery had a 90-day mortality of 1% (NBOCA: 3%) compared to 7.8% for emergencies (NBOCA: 10.5%).

Conclusion

Despite the added constraints of the COVID19 pandemic, CRC resection in our unit remains safe with better outcomes than the national standard. We have demonstrated that with adequate precaution and a concerted team effort, delivery of safe care with reasonable outcome is achievable.

ETMM-04. AURKA INHIBITION REPROGRAMS METABOLISM AND IS SYNTHETICALLY LETHAL WITH FATTY ACID OXIDATION INHIBITION IN GLIOBLASTOMA MODEL SYSTEMS

Aurora kinase A (AURKA) has emerged as a viable drug target for glioblastoma (GBM), the most common malignant primary brain tumor in adults with a life expectancy of 12–15 months. However, resistance to therapy remains a critical issue, which partially may be driven by reprogramming of metabolism. By integration of transcriptome, chromatin immunoprecipitation with sequencing (CHIP-seq.), assay for transposase-accessible chromatin with sequencing (ATAC-seq.), proteomic and metabolite screening followed by carbon tracing (U-¹³C-Glucose, U-¹³C-Glutamine and U-¹³C-Palmitic acid) and extracellular flux analysis we provided evidence that genetic (shRNA and CRISPR/Cas9) and pharmacological (Alisertib) AURKA inhibition elicited substantial metabolic reprogramming supported in part by inhibition of MYC targets and concomitant activation of PPARA signaling. While glycolysis was suppressed by AURKA inhibition, we noted a compensatory increase in oxygen consumption rate fueled by enhanced fatty acid oxidation (FAO). Whereas interference with AURKA elicited a suppression of c-Myc, we detected an upregulation of PGC1A, a master regulator of oxidative metabolism. Silencing of PGC1A reversed AURKAi mediated metabolic reprogramming and sensitized GBM cells to AURKAi driven reduction of cellular viability. Chromatin immunoprecipitation experiments showed binding of c-Myc to the promoter region of PGC1A, which is abrogated by AURKA inhibition and in turn unleashed PGC1A expression. Consistently, ATAC-seq. confirmed higher accessibility of a MYC binding region within the PGC1A promoter, suggesting that MYC acts as a repressor of PGC1A. Combining alisertib with inhibitors of FAO or the electron transport chain exerted substantial synergistic growth inhibition in PDX lines in vitro and extension of overall survival in orthotopic GBM PDX models without induction of toxicity in normal tissue. In summary, these findings support that simultaneous targeting of oxidative energy metabolism and AURKAi might be a potential novel therapy against GBM.

TAMI-33. AURKA INHIBITION REPROGRAMS METABOLISM AND IS SYNTHETICALLY LETHAL WITH FATTY ACID OXIDATION INHIBITION IN GLIOBLASTOMA

Aurora kinase A (AURKA) has emerged as a viable drug target for glioblastoma (GBM), the most common malignant primary brain tumor in adults with a life expectancy of 12-15 months. However, resistance to therapy remains a critical issue, which partially may be driven by reprogramming of metabolism. By integration of transcriptome, chromatin immunoprecipitation with sequencing (CHIP-seq.), assay for transposase-accessible chromatin with sequencing (ATAC-seq.), proteomic and metabolite screening followed by carbon tracing (U-13C-Glucose, U-13C-Glutamine and U-13C-Palmitic acid) and extracellular flux analysis we provided evidence that genetic (shRNA and CRISPR/Cas9) and pharmacological (Alisertib) AURKA inhibition elicited substantial metabolic reprogramming mediated in part by inhibition of MYC targets and concomitant activation of PPARA (e.g. PGC1A) signaling. While glycolysis was suppressed by AURKA inhibition, we noted a compensatory increase in oxygen consumption rate (OCR) fueled by fatty acid oxidation (FAO). Whereas interference with AURKA elicited a suppression of c-Myc, we detected an upregulation of PGC1A, a master regulator of oxidative metabolism, upon AURKA inhibition. Silencing of PGC1A reversed the increase in OCR and sensitized GBM cells to AURKA inhibition mediated reduction in cellular viability. CHIP experiments confirmed binding of c-Myc to the promoter region of PGC1A, which is abrogated by AURKA inhibition and in turn unleashed PGC1A expression. ATAC-seq. confirmed higher accessibility of the MYC binding region within the PGC1A promoter. Forced expression of c-Myc blocked AURKA inhibition mediated increase of PGC1A, suggesting that c-Myc acted as a repressor. To interfere with this oxidative metabolic reprogramming, we combined AURKA inhibitors with blockers of FAO (etomoxir), which elicited substantial synergistic growth inhibition and extension of overall survival in orthotopic patient derived xenografts of GBM in mice without induction of toxicity in normal tissue. Taken together, these data support that simultaneous targeting of oxidative metabolism and AURKA inhibition might be a potential novel therapy against GBM.

Luteolin Induces Cytotoxicity in Mix Cellularity Classical Hodgkin's Lymphoma via Caspase Activated-cell Death

BACKGROUND/AIM

We investigated the effects of luteolin (LUT) on classical Hodgkin's lymphoma (cHL), since such studies in malignant lymphomas are lacking.

MATERIALS AND METHODS

Effect of LUT on cell growth was assessed with water-soluble tetrazolium 1 (WST-1) cell proliferation assay and automated hemocytometry on trypan blue-exclusion assay. Cell death was investigated with acridine orange/ethidium bromide live-dead assay, propidium iodide (PI) flow cytometry, and Annexin-V-PI microscopy. Caspase activation was studied using CellEvent Caspase-3/7 Green detection reagent. High resolution immunofluorescence microscopy was used to detect cleaved-PARP-1.

RESULTS

LUT induced a dose-dependent decrease in the growth of KMH2 and L428 cells, cellular models of mix-cellularity (MC) and nodular sclerosis (NS) cHL, respectively. However, LUT induced cell death only in KMH2, at a higher concentration, and this was associated with caspase activation and cleaved PARP-1.

CONCLUSION

LUT induces cytotoxicity in the MC-cHL cellular model KMH2 via caspase activation.

Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

HDAC inhibitors elicit metabolic reprogramming by targeting super-enhancers in glioblastoma models

The Warburg effect is a tumor-related phenomenon that could potentially be targeted therapeutically. Here, we showed that glioblastoma (GBM) cultures and patients' tumors harbored super-enhancers in several genes related to the Warburg effect. By conducting a transcriptome analysis followed by ChIP-Seq coupled with a comprehensive metabolite analysis in GBM models, we found that FDA-approved global (panobinostat, vorinostat) and selective (romidepsin) histone deacetylase (HDAC) inhibitors elicited metabolic reprogramming in concert with disruption of several Warburg effect-related super-enhancers. Extracellular flux and carbon-tracing analyses revealed that HDAC inhibitors blunted glycolysis in a c-Myc-dependent manner and lowered ATP levels. This resulted in the engagement of oxidative phosphorylation (OXPHOS) driven by elevated fatty acid oxidation (FAO), rendering GBM cells dependent on these pathways. Mechanistically, interference with HDAC1/-2 elicited a suppression of c-Myc protein levels and a concomitant increase in 2 transcriptional drivers of oxidative metabolism, PGC1α and PPARD, suggesting an inverse relationship. Rescue and ChIP experiments indicated that c-Myc bound to the promoter regions of PGC1α and PPARD to counteract their upregulation driven by HDAC1/-2 inhibition. Finally, we demonstrated that combination treatment with HDAC and FAO inhibitors extended animal survival in patient-derived xenograft model systems in vivo more potently than single treatments in the absence of toxicity.

Cyclin A2 is essential for mouse gonocyte maturation

In mammals, male gonocytes are derived from primordial germ cells during embryogenesis, enter a period of mitotic proliferation, and then become quiescent until birth. After birth, the gonocytes proliferate and migrate from the center of testicular cord toward the basement membrane to form the pool of spermatogonial stem cells (SSCs) and establish the SSC niche architecture. However, the molecular mechanisms underlying gonocyte proliferation, migration and differentiation are largely unknown. Cyclin A2 is a key component of the cell cycle and required for cell proliferation. Here, we show that cyclin A2 is required in mouse male gonocyte development and the establishment of spermatogenesis in the neonatal testis. Loss of cyclin A2 function in embryonic gonocytes by targeted gene disruption affected the regulation of the male gonocytes to SSC transition, resulting in the disruption of SSC pool formation, imbalance between SSC self-renewal and differentiation, and severely abnormal spermatogenesis in the adult testis.

Metabolic Reprogramming by c-MET Inhibition as a Targetable Vulnerability in Glioblastoma

The elucidation of better treatments for solid tumors and especially malignant glial tumors is a priority. Better understanding of the molecular underpinnings of treatment response and resistance are critical determinants in the success for this endeavor. Recently, a battery of novel tools have surfaced that allow to interrogate tumor cell metabolism to more precise extent than this was possible in the earlier days. At the forefront of these developments are the extracellular flux and carbon tracing analyses. Through utilization of these techniques our group made the recent observation that acute and chronic c-MET inhibition drives fatty acid oxidation that in turn can be therapeutically targeted for drug combination therapies. Herein, we summarize and comment on some of our key findings related to this study.

Novel IDH1-Targeted Glioma Therapies

Mutations in the isocitrate dehydrogenase (IDH) 1 gene are commonly found in human glioma, with the majority of low-grade gliomas harboring a recurrent point mutation (IDH1 R132H). Mutant IDH reveals an altered enzymatic activity leading to the synthesis of 2-hydroxyglutarate, which has been implicated in epigenetic mechanisms of oncogenesis. Nevertheless, it is unclear exactly how IDH mutations drive glioma initiation and progression, and it is also not clear why tumors with this mutation generally have a better prognosis than IDH wild-type tumors. Recognition of the high frequency of IDH mutations in glioma [and also in other malignancies, including acute myeloid leukemia (AML) and cholangiocarcinoma] have led to the development of a number of targeted agents that can inhibit these enzymes. Enasidenib and ivosidenib have both gained regulatory approval for IDH mutant AML. Both agents are still in early clinical phases for glioma therapy, as are a number of additional candidates (including AG-881, BAY1436032, and DS1001). A marked clinical problem in the development of these agents is overcoming the blood-brain barrier. An alternative approach to target the IDH1 mutation is by the induction of synthetic lethality with compounds that target poly (ADP-ribose) polymerase (PARP), glutamine metabolism, and the Bcl-2 family of proteins. We conclude that within the last decade, several approaches have been devised to therapeutically target the IDH1 mutation, and that, potentially, both IDH1 inhibitors and synthetic lethal approaches might be relevant for future therapies.

CBMT-15. MET INHIBITION DRIVES PGC1A DEPENDENT METABOLIC REPROGRAMMING AND ELICITS UNIQUE METABOLIC VULNERABILITIES IN GLIOBLASTOMA

The receptor kinase, c-MET, has emerged as a target for glioblastoma therapy. However, treatment resistance evolves inevitably. By performing a global metabolite screen with metabolite set enrichment coupled with transcriptome and gene set enrichment analysis and proteomic screening, we have identified substantial reprogramming of tumor metabolism, involving oxidative phosphorylation and fatty acid oxidation (FAO) with a substantial accumulation of acyl-carnitines accompanied by an increase of PGC1a in response to genetic (shRNA and CRISPR/Cas9) and pharmacological (crizotinib) inhibition of c-MET. Extracellular flux and carbon tracing analyses (U-13C-Glucose and U-13C-Glutamine) demonstrated enhanced oxidative metabolism, which was driven by FAO and supported by increased anaplerosis of glucose carbons. These findings were observed in concert with increased number and fusion of mitochondria and production of reactive oxygen species (ROS). Genetic interference with PGC1a rescued this oxidative phenotype driven by c-MET inhibition. Silencing and chromatin immunoprecipitation experiments demonstrated that CREB regulates the expression of PGC1a in the context of c-MET inhibition. Interference with both oxidative phosphorylation (metformin, oligomycin) and beta-oxidation of fatty acids (etomoxir) enhanced the anti-tumor efficacy of c-MET inhibition. Moreover, based on a high-throughput drug screen, we show that gamitrinib along with c-MET inhibition results in synergistic cell death. Finally, utilizing patient-derived xenograft models, we provide evidence that the combination treatments (crizotinib+etomoxir and crizotinib+gamitrinib) were significantly more efficacious than single treatment without induction of toxicity. Collectively, we have unraveled the mechanistic underpinnings of c-MET inhibitor treatment and identified novel combination therapies that may enhance the therapeutic efficacy of c-MET inhibition.

MET Inhibition Elicits PGC1α-Dependent Metabolic Reprogramming in Glioblastoma

The receptor kinase c-MET has emerged as a target for glioblastoma therapy. However, treatment resistance emerges inevitably. Here, we performed global metabolite screening with metabolite set enrichment coupled with transcriptome and gene set enrichment analysis and proteomic screening, and identified substantial reprogramming of tumor metabolism involving oxidative phosphorylation and fatty acid oxidation (FAO) with substantial accumulation of acyl-carnitines accompanied by an increase of PGC1α in response to genetic (shRNA and CRISPR/Cas9) and pharmacologic (crizotinib) inhibition of c-MET. Extracellular flux and carbon tracing analyses (U-¹³C-glucose, U-¹³C-glutamine, and U-¹³C-palmitic acid) demonstrated enhanced oxidative metabolism, which was driven by FAO and supported by increased anaplerosis of glucose carbons. These findings were observed in concert with increased number and fusion of mitochondria and production of reactive oxygen species. Genetic interference with PGC1α rescued this oxidative phenotype driven by c-MET inhibition. Silencing and chromatin immunoprecipitation experiments demonstrated that cAMP response elements binding protein regulates the expression of PGC1α in the context of c-MET inhibition. Interference with both oxidative phosphorylation (metformin, oligomycin) and β-oxidation of fatty acids (etomoxir) enhanced the antitumor efficacy of c-MET inhibition. Synergistic cell death was observed with c-MET inhibition and gamitrinib treatment. In patient-derived xenograft models, combination treatments of crizotinib and etomoxir, and crizotinib and gamitrinib were significantly more efficacious than single treatments and did not induce toxicity. Collectively, we have unraveled the mechanistic underpinnings of c-MET inhibition and identified novel combination therapies that may enhance its therapeutic efficacy. SIGNIFICANCE: c-MET inhibition causes profound metabolic reprogramming that can be targeted by drug combination therapies.

Activation of LXRβ inhibits tumor respiration and is synthetically lethal with Bcl-xL inhibition

Liver-X-receptor (LXR) agonists are known to bear anti-tumor activity. However, their efficacy is limited and additional insights regarding the underlying mechanism are necessary. By performing transcriptome analysis coupled with global polar metabolite screening, we show that LXR agonists, LXR623 and GW3965, enhance synergistically the anti-proliferative effect of BH3 mimetics in solid tumor malignancies, which is predominantly mediated by cell death with features of apoptosis and is rescued by exogenous cholesterol. Extracellular flux analysis and carbon tracing experiments (U-13 C-glucose and U-13 C-glutamine) reveal that within 5 h, activation of LXRβ results in reprogramming of tumor cell metabolism, leading to suppression of mitochondrial respiration, a phenomenon not observed in normal human astrocytes. LXR activation elicits a suppression of respiratory complexes at the protein level by reducing their stability. In turn, energy starvation drives an integrated stress response (ISR) that up-regulates pro-apoptotic Noxa in an ATF4-dependent manner. Cholesterol and nucleotides rescue from the ISR elicited by LXR agonists and from cell death induced by LXR agonists and BH3 mimetics. In conventional and patient-derived xenograft models of colon carcinoma, melanoma, and glioblastoma, the combination treatment of ABT263 and LXR agonists reduces tumor sizes significantly stronger than single treatments. Therefore, the combination treatment of LXR agonists and BH3 mimetics might be a viable efficacious treatment approach for solid malignancies.

Activation of LXR Receptors and Inhibition of TRAP1 Causes Synthetic Lethality in Solid Tumors

Cholesterol is a pivotal factor for cancer cells to entertain their relentless growth. In this case, we provide a novel strategy to inhibit tumor growth by simultaneous activation of liver-X-receptors and interference with Tumor Necrosis Factor Receptor-associated Protein 1 (TRAP1). Informed by a transcriptomic and subsequent gene set enrichment analysis, we demonstrate that inhibition of TRAP1 results in suppression of the cholesterol synthesis pathway in stem-like and established glioblastoma (GBM) cells by destabilizing the transcription factor SREBP2. Notably, TRAP1 inhibition induced cell death, which was rescued by cholesterol and mevalonate. Activation of liver X receptor (LXR) by a clinically validated LXR agonist, LXR623, along with the TRAP1 inhibitor, gamitrinib (GTPP), results in synergistic reduction of tumor growth and cell death induction in a broad range of solid tumors, which is rescued by exogenous cholesterol. The LXR agonist and TRAP1 inhibitor mediated cell death is regulated at the level of Bcl-2 family proteins with an elevation of pro-apoptotic Noxa. Silencing of Noxa and its effector BAK attenuates cell death mediated by the combination treatment of LXR agonists and TRAP1 inhibition. Combined inhibition of TRAP1 and LXR agonists elicits a synergistic activation of the integrated stress response with an increase in activating transcription factor 4 (ATF4) driven by protein kinase RNA-like endoplasmic reticulum kinase (PERK). Silencing of ATF4 attenuates the increase of Noxa by using the combination treatment. Lastly, we demonstrate in patient-derived xenografts that the combination treatment of LXR623 and gamitrinib reduces tumor growth more potent than each compound. Taken together, these results suggest that TRAP1 inhibition and simultaneous activation of LXR might be a potent novel treatment strategy for solid malignancies.

Dual Inhibition of Bcl-2/Bcl-xL and XPO1 is synthetically lethal in glioblastoma model systems

XPO1 has recently emerged as a viable treatment target for solid malignancies, including glioblastoma (GBM), the most common primary malignant brain tumor in adults. However, given that tumors become commonly resistant to single treatments, the identification of combination therapies is critical. Therefore, we tested the hypothesis that inhibition of anti-apoptotic Bcl-2 family members and XPO1 are synthetically lethal. To this purpose, two clinically validated drug compounds, the BH3-mimetic, ABT263, and the XPO1 inhibitor, Selinexor, were used in preclinical GBM model systems. Our results show that inhibition of XPO1 reduces cellular viability in glioblastoma cell cultures. Moreover, addition of ABT263 significantly enhances the efficacy of XPO1 inhibition on the reduction of cellular viability, which occurs in a synergistic manner. While selinexor inhibits the proliferation of glioblastoma cells, the combination treatment of ABT263 and selinexor results in substantial induction of cell death, which is accompanied by activation of effector- initiator caspases and cleavage of PARP. Mechanistically we find that XPO1 inhibition results in down-regulation of anti-apoptotic Mcl-1 and attenuates ABT263 driven Mcl-1 up-regulation. Consistently, siRNA mediated silencing of Mcl-1 sensitizes for ABT263 mediated cell death and partially for the combination treatment. By using a human patient-derived xenograft model of glioblastoma in mice, we demonstrate that the combination treatment of ABT263 and Selinexor reduces tumor growth significantly more than each compound alone. Collectively, these results suggest that inhibition of XPO1 and Bcl-2/Bcl-xL might be a potential strategy for the treatment of malignant glial tumors.

Sex-specific behavioral traits in the Brd2 mouse model of juvenile myoclonic epilepsy

Idiopathic generalized epilepsy represents about 30-35% of all epilepsies in humans. The bromodomain BRD2 gene has been repeatedly associated with the subsyndrome of juvenile myoclonic epilepsy (JME). Our previous work determined that mice haploinsufficient in Brd2 (Brd2+/-) have increased susceptibility to provoked seizures, develop spontaneous seizures and have significantly decreased gamma-aminobutyric acid (GABA) markers in the direct basal ganglia pathway as well as in the neocortex and superior colliculus. Here, we tested male and female Brd2+/- and wild-type littermate mice in a battery of behavioral tests (open field, tube dominance test, elevated plus maze, Morris water maze and Barnes maze) to identify whether Brd2 haploinsufficiency is associated with the human behavioral patterns, the so-called JME personality. Brd2+/- females but not males consistently displayed decreased anxiety. Furthermore, we found a highly significant dominance trait (aggression) in the Brd2+/- mice compared with the wild type, more pronounced in females. Brd2+/- mice of either sex did not differ from wild-type mice in spatial learning and memory tests. Compared with wild-type littermates, we found decreased numbers of GABA neurons in the basolateral amygdala, which is consistent with the increase in aggressive behavior. Our results indicate that Brd2+/- haploinsufficient mice show no cognitive impairment but have behavioral traits similar to those found in patients with JME (recklessness, aggression). This suggests that either the BRD2 gene is directly responsible for influencing many traits of JME or it controls upstream regulators of individual phenotypes.

Sexual abuse in bariatric surgery candidates: impact on weight loss after surgery: a systematic review

Bariatric surgery is becoming more and more influential as efficient weight loss therapy for the morbidly obese. As many studies propose a relationship between sexual abuse and obesity in general, but especially with regard to weight regain after successful weight loss, sexual abuse might also have a crucial impact on the outcome of the surgical procedures. This review examines the literature comparing weight loss after bariatric surgery in sexually abused and non-abused individuals. We conducted a systematic electronic literature search covering PubMed/Medline, ScienceDirect, PsychInfo and Web of Science. While 13 studies examined prevalence rates of sexual abuse among bariatric patients, eight studies explicitly investigated the effect of sexual abuse on surgery outcome. We hypothesized that individuals with a history of sexual abuse lose less weight compared to individuals with no such abuse history. At first glance, only three out of eight studies demonstrated significantly reduced weight loss in the sexually abused patients. However, a closer investigation of all studies revealed that patients with abuse experiences may indeed tend to lose less weight initially. Still, this sub-population apparently benefits from the surgical procedure, as revealed by increased weight loss over time. Reasons for these mixed results are discussed, as well as the clinical implications that can be drawn from these studies.

The bromodomain-containing gene BRD2 is regulated at transcription, splicing, and translation levels

The human BRD2 gene has been linked and associated with a form of common epilepsy and electroencephalographic abnormalities. Disruption of Brd2 in the mouse revealed that it is essential for embryonic neural development and that viable Brd2(+/-) heterozygotes show both decreased GABAergic neuron counts and increased susceptibility to seizures. To understand the molecular mechanisms by which mis-expression of BRD2 might contribute to epilepsy, we examined its regulation at multiple levels. We discovered that BRD2 expresses distinct tissue-specific transcripts that originate from different promoters and have strikingly different lengths of 5' untranslated regions (5'UTR). We also experimentally confirmed the presence of a highly conserved, alternatively spliced exon, inclusion of which would result in a premature termination of translation. Downstream of this alternative exon is a polymorphic microsatellite (GT-repeats). Manipulation of the number of the GT-repeats revealed that the length of the GT-repeats affects the ratio of the two alternative splicing products. In vitro translation and expression in cultured cells revealed that among the four different mRNAs (long and short 5'UTR combined with regular and alternative splicing), only the regularly spliced mRNA with the short 5'UTR yields full-length protein. In situ hybridization and immunohistochemical studies showed that although Brd2 mRNA is expressed in both the hippocampus and cerebellum, Brd2 protein only can be detected in the cerebellar Purkinje cells and not in hippocampal cells. These multiple levels of regulation would likely affect the production of functional BRD2 protein during neural development and hence, its role in the etiology of seizure susceptibility.

[Open abdomen 2009. A national survey of open abdomen treatment in Germany]

BACKGROUND

Open abdomen (OA) treatment has been established worldwide. This survey examines the current status of OA treatment in Germany.

MATERIAL AND METHODS

A national survey was conducted between October 2008 and September 2009 by questionnaires sent to 1,219 surgical departments. Data were evaluated descriptively.

RESULTS

The response rate was 38% overall and 69% for university departments. Open abdomen treatment is used by 94% of all respondents. Most commonly used are staged abdominal lavage (87%), a commercial abdominal dressing system (82%), planned ventral hernia (69%), and other intra-abdominal dressings (e.g. vacuum pack 15%, Bogotá bag 5%). Nearly half of the respondents (46%) indicated a modification of their strategy towards vacuum techniques during the last 5 years.

CONCLUSIONS

Open abdomen procedures are widely used in German surgical departments. This survey indicates a shift of treatment strategies towards vacuum techniques but even though predominant, the effectiveness and safety of these techniques must still be confirmed by prospective controlled trials. This survey helps to identify relevant clinical questions and enables focused trial networking.

GABAergic neuron deficit as an idiopathic generalized epilepsy mechanism: the role of BRD2 haploinsufficiency in juvenile myoclonic epilepsy

Idiopathic generalized epilepsy (IGE) syndromes represent about 30% of all epilepsies. They have strong, but elusive, genetic components and sex-specific seizure expression. Multiple linkage and population association studies have connected the bromodomain-containing gene BRD2 to forms of IGE. In mice, a null mutation at the homologous Brd2 locus results in embryonic lethality while heterozygous Brd2+/− mice are viable and overtly normal. However, using the flurothyl model, we now show, that compared to the Brd2+/+ littermates, Brd2+/− males have a decreased clonic, and females a decreased tonic-clonic, seizure threshold. Additionally, long-term EEG/video recordings captured spontaneous seizures in three out of five recorded Brd2+/− female mice. Anatomical analysis of specific regions of the brain further revealed significant differences in Brd2+/− vs +/+ mice. Specifically, there were decreases in the numbers of GABAergic (parvalbumin- or GAD67-immunopositive) neurons along the basal ganglia pathway, i.e., in the neocortex and striatum of Brd2+/− mice, compared to Brd2+/+ mice. There were also fewer GABAergic neurons in the substantia nigra reticulata (SNR), yet there was a minor, possibly compensatory increase in the GABA producing enzyme GAD67 in these SNR cells. Further, GAD67 expression in the superior colliculus and ventral medial thalamic nucleus, the main SNR outputs, was significantly decreased in Brd2+/− mice, further supporting GABA downregulation. Our data show that the non-channel-encoding, developmentally critical Brd2 gene is associated with i) sex-specific increases in seizure susceptibility, ii) the development of spontaneous seizures, and iii) seizure-related anatomical changes in the GABA system, supporting BRD2's involvement in human IGE.

Early supplementation of parenteral nutrition is capable of improving quality of life, chemotherapy-related toxicity and body composition in patients with advanced colorectal carcinoma undergoing palliative treatment: results from a prospective, randomized clinical trial

AIM

Patients suffering from advanced colorectal cancer can experience unintended weight loss and/or treatment-induced gastrointestinal toxicity. Based on current evidence, the routine use of parenteral nutrition (PN) for patients with colorectal cancer is not recommended. This study evaluates the effect of PN supplementation on body composition, quality of life (QoL), chemotherapy-associated side effects and survival in patients with advanced colorectal cancer.

METHOD

Eighty-two patients with advanced colorectal cancer receiving a palliative chemotherapy were prospectively randomized to either oral enteral nutrition supplement (PN-) or oral enteral nutrition supplement plus supplemental PN (PN+). Every 6 weeks body weight, body mass index (BMI), chemotherapy-associated side effects and caloric intake were assessed, haemoglobin and serum albumin were measured. Body composition was assessed by body impedance analysis, and QoL was evaluated by European Organization for Research and Treatment of Cancer (EORTC) QLQC30 questionnaire.

RESULTS

No differences were evident at baseline between the groups for age, sex, diagnosis, weight, BMI or QoL. A difference in BMI was observed by week 36, whereas differences of the mean body cell mass could be observed from week 6, albumin dropped significantly in the PN- group in week 36 and QoL showed significant differences from week 18. Chemotherapy-associated side effects were higher in PN-. The survival rate was significantly greater in the PN+ group.

CONCLUSION

A supplementation with PN slows weight loss, stabilizes body-composition and improves QoL in patients with advanced colorectal cancer. Furthermore, it can reduce chemotherapy-related side effects.

Non-surgical oncology - Guidelines on Parenteral Nutrition, Chapter 19

Reduced nutritional state is associated with unfavourable outcomes and a lower quality of life in patients with malignancies. Patients with active tumour disease frequently have insufficient food intake. The resting energy expenditure in cancer patients can be increased, decreased, or remain unchanged compared to predicted values. Tumours may result in varying degrees of systemic pro-inflammatory processes with secondary effects on all significant metabolic pathways. Therapeutic objectives are to stabilise nutritional state with oral/enteral nutrition and parenteral nutrition (PN) and thus to prevent or reduce progressive weight loss. The maintenance or improvement of quality of life, and the increase in the effectiveness and a reduction in the side-effects of antitumor therapy are further objectives. Indications for PN in tumour patients are essentially identical to those in patients with benign illnesses, with preference given to oral or enteral nutrition when feasible. A combined nutritional concept is preferred if oral or enteral nutrition are possible but not sufficient. There are generally no accepted standards for ideal energy and nutrient intakes in oncological patients, particularly when exclusive artificial nutrition is administered. The use of PN as a general accompaniment to radiotherapy or chemotherapy is not indicated, but PN is indicated in chronic severe radiogenic enteritis or after allogenic transplantation with pronounced mucositis or GvH-related gastrointestinal damage for prolonged periods, with particular attention to increased risk of bleeding and infection. No PN is necessary in the terminal phase.

Double bromodomain-containing gene Brd2 is essential for embryonic development in mouse

The BET subfamily of bromodomain-containing genes is characterized by the presence of two bromodomains and a unique ET domain at their carboxyl termini. Here, we show that the founding member of this subfamily, Brd2, is an essential gene by generating a mutant mouse line lacking Brd2 function. Homozygous Brd2 mutants are embryonic lethal, with most Brd2(-/-) embryos dying by embryonic day 11.5. Before death, the homozygous embryos were notably smaller and exhibited abnormalities in the neural tube where the gene is highly expressed. Brd2-deficient embryonic fibroblast cells were observed to proliferate more slowly than controls. Experiments to explore whether placental insufficiency could be a cause of the embryonic lethality showed that injecting diploid mutant embryonic stem cells into tetraploid wild-type blastocysts did not rescue the lethality; that is Brd2-deficient embryos could not be rescued by wild-type extraembryonic tissues. Furthermore, there were enhanced levels of cell death in Brd2-deficient embryos.

Evidence of thromboembolism prophylaxis in bariatric surgery-results of a quality assurance trial in bariatric surgery in Germany from 2005 to 2007 and review of the literature

BACKGROUND

Since January 1st, 2005, the current situation for bariatric surgery has been examined by means of a voluntary quality assurance study in Germany with a multicenter design in which 38 hospitals and surgical departments participated. The data are registered in cooperation with the Institute of Quality Assurance in Surgery at the Otto-von-Guericke University of Magdeburg (Germany).

METHODS

Data describing peri-interventional characteristics were prospectively documented in an internet online data registry. All primary bariatric procedures performed since January 1st, 2005, were registered. In addition, reoperations in patients who had previously undergone primary surgical intervention were included. As a representative excerpt from the overall prospective multicenter observational study on obesity surgery, data on the type, regimen, and time course of deep venous thrombosis (DVT) prophylaxis were documented. From the number and spectrum of complications, the incidences of clinically manifest DVT or pulmonary embolism (PE) were derived during the in-hospital course and follow-up in conjunction with the type of surgical procedure and body mass index (BMI).

RESULTS

Overall, 3,122 bariatric procedures were performed at 38 German hospitals between January 2005 and December 2007. These procedures were subdivided into 2,869 primary operations and 253 revisions (sex ratio, male to female = 25.6:74.4%). The average BMI of all patients was 48.5 kg/m(2) in 2005, 48.4 kg/m(2) in 2006, and 48.0 kg/m(2) in 2007. In 2005 and 2006, gastric banding (GB) was the most commonly performed operation, followed by Roux-en-Y gastric bypass (RYGBP). In 2007, RYGBP was carried out in 42.1% of all bariatric procedures. Interestingly, the incidence of deep venous thrombosis (DVT) was only 0.06%, whereas PE occurred in 0.06% of patients only after hospital discharge. The DVT prophylaxis protocol used has been changed for the last 2 years: the majority of patients with a BMI above 50 kg/m(2) received low-molecular-weight heparin twice a day.

CONCLUSION

In Germany, a trend from GB to sleeve gastrectomy (SG) and malabsorptive approach has been evaluated. This trend is associated with differences of the DVT prophylaxis regimen in the profile of bariatric surgical patients depending on BMI and the type of bariatric procedure. Despite the low incidence of DVT and pulmonary embolism (PE) detected, there is a lack of evidence on a reasonable regimen for sufficient DVT prophylaxis in bariatric surgery; instead, there are only recommendations from the guidelines and statements of a specific medical society. Therefore, prospective studies are necessary to determine the optimal DVT prophylaxis for bariatric surgical patients as well as obese patients undergoing surgery.

'Fast-track' colonic surgery in Austria and Germany--results from the survey on patterns in current perioperative practice

OBJECTIVE

'Fast-track' rehabilitation has been shown to accelerate recovery, reduce general morbidity and decrease hospital stay after elective colonic surgery. Despite this evidence, there is no information on the acceptance and utilization of these concepts among the entirety of Austrian and German surgeons.

METHOD

In 2006, a questionnaire concerning perioperative routines in elective, open colonic resection was sent to the chief surgeons of 1270 German and 120 Austrian surgical centres.

RESULTS

The response rate was 63% in Austria (76 centres) and 30% in Germany (385 centres). Mechanical bowel preparation is used by the majority (Austria, 91%; Germany, 94%); the vertical incision is the standard method of approach to the abdomen in Austria (79%) and Germany (83%), nasogastric decompression tubes are rarely used, one-third of the questioned surgeons in both countries use intra-abdominal drains. Half of the surgical centres allow the intake of clear fluids on the day of surgery and one-fifth offer solid food on that day. Epidural analgesia is used in three-fourths of the institutions.

CONCLUSION

Although there is an evident benefit of fast-track management, the survey shows that they are not yet widely used as a routine in Austria and Germany.

A nationwide survey on bariatric surgery in Germany--results 2005-2007

BACKGROUND

Most studies on bariatric surgery outcomes are performed as clinical trials or reflect the clinical experience in single centers. The status of bariatric surgery in Germany has been examined since January 1st, 2005 with the cooperation of clinics and hospitals at the Institute of Quality Assurance in Surgery at the Otto-von-Guericke University of Magdeburg (Germany).

METHODS

In this prospective multicenter observational study, the data obtained for all primary bariatric procedures, including all repeated operations, performed on consecutive patients with morbid obesity at participating hospitals from 2005 to 2007 were prospectively collected using an Internet online data registry. In particular, perioperative characteristics, such as the spectrum of diagnostic measurements, type of surgical procedures, and short- and long-term outcomes, were investigated.

RESULTS

During the study period, 629 surgical procedures were performed at 21 hospitals in 2005, 828 procedures at 32 hospitals in 2006, and 1,666 procedures at 35 hospitals in 2007. In 2005 and 2006, gastric banding was the most frequently performed operation, followed by the Roux-en-Y gastric bypass (RYGBP). In 2007, a RYGBP was carried out in 42.1% of all bariatric procedures. Among all patients, 74.4% were female. The mean body mass index (BMI) was 48.5 kg/m(2) in 2005, 48.4 kg/m(2) in 2006, and 48.0 kg/m(2) in 2007. Follow-up data after 12 months were available for 63.8% of the patients in 2005 and 2006; these data showed greater reduction of BMI after malabsorptive rather than restrictive bariatric procedures. The mortality was 0.1% (30 days) and 0.16% (overall).

CONCLUSION

As indicated by the worldwide trend, there is an ongoing change from restrictive bariatric procedures to malabsorptive procedures and sleeve gastrectomy. Although the BMIs of German patients undergoing bariatric surgery appear to be substantially higher than those of patients from most other countries, there were no differences in intraoperative and short-term complications or in overall outcomes during follow-up when compared with published studies.

[A survey of perioperative therapy for elective colon resection in Germany, 2006]

BACKGROUND

Despite the evidence that fast-track concepts in colon surgery lead to an enhanced recovery rate, there is no information on the prevalence and utilization of such programs in Germany.

METHODS

Based on a conventional sigmoid resection, we asked 1,270 surgical departments in Germany to describe their standard surgical procedures in a questionnaire.

RESULTS

The response rate was 385 (30.31%). A total of 96% use a bowel preparation, 83% a vertical incision, 10% use a nasogastric decompression for longer then 1 day, 34% avoid intra-abdominal drains, 51% allow clear fluids on the day of surgery, 13% offer solid food on the first day after surgery, 75% use epidural analgesia and 47% discharge the patients by the seventh day after surgery.

CONCLUSION

Although there is an evident benefit using fast-track concepts, they are not yet in wide use as a standard procedure. Further efforts have to be made to ensure that the majority of patients will benefit from these concepts.

Elektive Kolonresektionen in Deutschland

BACKGROUND

Fast-track rehabilitation after elective colon resection is an interdisciplinary multimodal procedure, which combines surgical and anesthesiological aspects. This leads to an improved and accelerated recovery and avoids perioperative complications. This survey focuses on the extent and use of such concepts in Germany.

METHODS

In January 2006, a questionnaire was sent to 1270 anesthesiology departments in Germany in which they were asked to describe the standard anesthesia procedures based on a conventional sigmoid resection.

RESULTS

The response rate was 385 out of 1270 (30.3%). Preoperative fasting of solid food 12 h before the operation was practiced in 52% and for 6 h in 44% of the clinics. For fluid intake the fasting time was 6 h in 47% and 2 h in 41%. Prophylactic measures for postoperative nausea and vomiting (PONV) were administered in 33% of clinics. Propofol (68%) was the leading narcotic, fentanyl (56%) and sufentanil (48%) were the most commonly used intraoperative analgesics and 75% of clinics used epidural analgesia.

CONCLUSION

In Germany the anesthesiological treatment after elective colon surgery adheres broadly to the evidence-based recommendations for fast-track concepts.

The first bromodomain of Brdt, a testis-specific member of the BET sub-family of double-bromodomain-containing proteins, is essential for male germ cell differentiation

Brdt is a testis-specific member of the distinctive BET sub-family of bromodomain motif-containing proteins, a motif that binds acetylated lysines and is implicated in chromatin remodeling. Its expression is restricted to the germ line, specifically to pachytene and diplotene spermatocytes and early spermatids. Targeted mutagenesis was used to generate mice carrying a mutant allele of Brdt, Brdt(Delta)(BD1), which lacks only the first of the two bromodomains that uniquely characterize BET proteins. Homozygous Brdt(Delta)(BD1/)(Delta)(BD1) mice were viable but males were sterile, producing fewer and morphologically abnormal sperm. Aberrant morphogenesis was first detected in step 9 elongating spermatids, and those elongated spermatids that were formed lacked the distinctive foci of heterochromatin at the peri-nuclear envelope. Quantitative reverse transcription (RT)-PCR showed threefold increased levels of histone H1t (Hist1h1t) in Brdt(Delta)(BD1/)(Delta)(BD1) testes and chromatin immunoprecipitation revealed that Brdt protein, but not Brdt(DeltaBD1) protein, was associated with the promoter of H1t. Intracytoplasmic sperm injection suggested that the DNA in the Brdt(Delta)(BD1) mutant sperm could support early embryonic development and yield functional embryonic stem cells. This is the first demonstration that deletion of just one of the two bromodomains in members of the BET sub-family of bromodomain-containing proteins has profound effects on in vivo differentiation.

An European survey of structure and organisation of nutrition support teams in Germany, Austria and Switzerland

BACKGROUND & AIMS

Nutritional support teams (NST) have been demonstrated to be an excellent mechanism for identifying patients in need of nutrition support, improving the efficacy of nutrition support in a variety of hospital environments. Focus of this study was the investigation of function, structure and organisation of NST in Germany (D), Austria (A) and Switzerland (CH).

METHODS

Prospective investigation of the function, structure and organisation of NST in D, A and CH, using standardised questionnaires.

RESULTS

From a total of 3071 hospitals in D, A and CH, NST have been established at 98 hospitals (3.2%). Their main activities were creating nutritional regimes (100%), education (87%) and monitoring nutrition therapy (92%). In general, the NST are not independently operating units but are affiliated to a special discipline. Seventy-one per cent of the physicians, 40% of the nurses and 69% of the dieticians in the NST held a nutrition-specific additional qualification. A total of 12% of the physicians, 37% of the nurses and 46% of the dieticians are exclusively responsible for the NST. A reduction of complications (88%) and cost saving (98%) were indicated since their establishment. The NST received in 32% funding support.

CONCLUSION

In D, A, CH neither a uniform nor comprehensive patient care by NST existed in 2004. Standards of practice, development of guidelines in clinical nutrition and better documentation in NSTs are necessary. Special efforts should be aimed at education of NST members and financing of teams.

Identification of unique, differentiation stage-specific patterns of expression of the bromodomain-containing genes Brd2, Brd3, Brd4, and Brdt in the mouse testis

The bromodomain, an evolutionarily conserved motif that binds acetyl-lysine on histones, is found in many chromatin-associated proteins, transcription factors, and in nearly all known histone acetyltransferases. The BET subclass of bromodomain-containing proteins contains two bromodomains and one ET domain and consists of at least four members in mouse and human, Brd2, Brd3, Brd4, and Brdt. We isolated mouse cDNAs for these genes and studied their expression patterns with particular focus on the testis. Northern hybridization revealed that Brd3 is most abundant in testis, ovary, placenta, uterus, and brain; that Brd4 is rather ubiquitously expressed but is most abundant in mid-gestation embryo, testis, ovary, and brain; and that Brdt is specifically expressed in testis. In situ hybridization and immunostaining on histological sections of mouse testes revealed a strikingly specific and dynamic change of cellular specificity in the germ line during the progression of spermatogenesis. Brd4 is expressed in spermatogonia, Brdt is only expressed in mid- to late-spermatocytes, Brd2 is expressed in diplotene spermatocytes and round spermatids and at low levels in spermatogonia, and Brd3 is expressed in round spermatids. This unique expression pattern suggests that genes in this subclass are not simply redundant. Rather, their expression is tightly regulated in the male germ cell lineage, suggesting that they likely have specific roles in different developmental stages and/or cell types.

Structure and organisation of 47 nutrition support teams in Germany: a prospective investigation in 2000 German hospitals in 1999

OBJECTIVE

Evaluation. Contrary to the Anglo-American region, very little is known in Germany on the structure and organisation of nutrition support teams (NST).

DESIGN

Prospective investigation of the structure and organisation of German NST, using standardised interview questionnaires.

SETTINGS

Hospitals with more than 250 beds in Germany.

SUBJECTS

German NST (n=47).

INTERVENTIONS

Face-to-face interview in 1999, using a standardised questionnaire.

RESULTS

From a total of 2000 German hospitals, NST have been established at 47 hospitals (2.3%). Most NST are affiliated to a large university hospital or an academic teaching hospital. In general, the NST are not independently operating units but are affiliated to a special discipline, and were in operation for an average of 8 y. The NST cared for a median of 65 outpatients annually. At the university hospitals in average, 477 in-patients were treated per year, at the teaching hospitals 400 and at all other hospitals 179. The work of the NST centred on enteral nutrition. A total of 47% of the physicians, 19% of the nurses and 19% of the dietitians in the NST held a nutrition-specific additional qualification. A total of 2% of the physicians, 68% of the nurses and 77% of the dietitians are exclusively responsible for the NST. More than 70% of the financing of the personnel was secured through third-party funds.

CONCLUSION

In Germany, neither uniform nor comprehensive patient care by NST existed in 1999. More than 50% of all NST members do not hold a nutrition-specific additional qualification. Frequently, besides their tasks in the team, the NST staff also carries out other clinical functions. Contrary to the American NST, the German NST are not interdisciplinary operating units but are primarily financed through third-party funds of the industry.

Targeted disruption of the mouse cis-retinol dehydrogenase gene: visual and nonvisual functions

It has been proposed that cis-retinol dehydrogenase (cRDH) acts within the body to catalyze the oxidation of 9-cis-retinol, an oxidative step needed for 9-cis-retinoic acid synthesis, the oxidation of 11-cis-retinol [an oxidative step needed for 11-cis-retinal (visual chromophore) synthesis], and 3 alpha-hydroxysteroid transformations. To assess in vivo the physiological importance of each of these proposed actions of cRDH, we generated cRDH-deficient (cRDH-/-) mice. The cRDH-/- mice reproduce normally and appear to be normal. However, the mutant mice do have a mild visual phenotype of impaired dark adaptation. This phenotype is evidenced by electroretinagram analysis of the mice and by biochemical measures of eye levels of retinoid intermediates during recovery from an intense photobleach. Although it is thought that cRDH is expressed in the eye almost solely in retinal pigment epithelial cells, we detected cRDH expression in other retinal cells, including ganglion cells, amacrine cells, horizontal cells, and the inner segments of the rod photoreceptor cells. Aside from the eye, there are no marked differences in retinoid levels in other tissues throughout the body for cRDH-/- compared with cRDH+/+ mice. Moreover, we did not detect any non-visual phenotypic changes for cRDH-/- mice, suggesting that these mice do not have problems in metabolizing 3 alpha-hydroxysteroids.Thus, cRDH may act essentially in the visual cycle but is redundant for catalyzing 9-cis-retinoic acid formation and 3 alpha-hydroxysteroid metabolism.

[Requirement for the structure and function of a nutritional support team]

Procedures in clinical nutrition have gained both invasiveness as well as the complexity. Thus improved education of professionals and their alliance in hospital based nutritional support teams (NST) is demanding. Two forms of collaboration, the "interdisciplinary nutritional committee" and the "department for nutritional therapy", are discussed. It is the goal of this contribution to present structure and tasks of an independently working department for nutritional support therapy. The pertinent areas of activity are composed as followed: clinical nutritional therapy, home nutrition, education, research, and quality management. The team members include the physician, the dietitian, the nurse, the nutritionist, and the pharmacist. The individual tasks as well as the areas of responsibility are presented. We discuss, whether nutritional support teams might be suitable to achieve cost reduction, provided adequate working conditions are available. Issues like "performance related reimbursement" and "NST certification" by health care organizations are discussed. We also elude to the option to merge services with other health care providers in order to built up an inter-disciplinary organization system. We conclude that nutritional support teams have to be prepared to meet hospital needs. Costs/benefit balances have to be assessable and must be documented. Although the effectiveness of selected nutritional support teams was clearly shown, it is the challenge of each individual team to produce proof of effectiveness for itself. Acceptable working conditions, however, should be provided as they have to be considered indispensable to achieve high quality performance.