Do Neuroprognostic Studies Account for Self-Fulfilling Prophecy Bias in Their Methodology? The SPIN Protocol for a Systematic Review

Self-fulfilling prophecy bias occurs when a perceived prognosis leads to treatment decisions that inherently modify outcomes of a patient, and thus, overinflate the prediction performance of prognostic methods. The goal of this series of systematic reviews is to characterize the extent to which neuroprognostic studies account for the potential impact of self-fulfilling prophecy bias in their methodology by assessing their adequacy of disclosing factors relevant to this bias.

Methods

Studies evaluating the prediction performance of neuroprognostic tools in cardiac arrest, malignant ischemic stroke, traumatic brain injury, subarachnoid hemorrhage, and spontaneous intracerebral hemorrhage will be identified through PubMed, Cochrane, and Embase database searches. Two reviewers blinded to each other's assessment will perform screening and data extraction of included studies using Distiller SR and following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We will abstract data pertinent to the methodology of the studies relevant to self-fulfilling prophecy bias.

Results

We will conduct a descriptive analysis of the data. We will summarize the reporting of mortality according to timing and mode of death, rates of exposure to withdrawal of life-sustaining therapy, reasoning behind limitations of supportive care, systematic use of standardized neuroprognostication algorithms and whether the tool being investigated is part of such assessments, and blinding of treatment team to results of neuroprognostic test being evaluated.

CONCLUSIONS

We will identify if neuroprognostic studies have been transparent in their methodology to factors that affect the self-fulfilling prophecy bias. Our results will serve as the foundation for standardization of neuroprognostic study methodologies by refining the quality of the data derived from such studies.

Mismatch repair deficiency, chemotherapy and survival for resectable gastric cancer: an observational study from the German staR cohort and a meta-analysis

PURPOSE

In a post hoc analysis of the MAGIC trial, patients with curatively resected gastric cancer (GC) and mismatch repair (MMR) deficiency (MMRd) had better median overall survival (OS) when treated with surgery alone but worse median OS when treated with additional chemotherapy. Further data are required to corroborate these findings.

METHODS

Between April 2013 and December 2018, 458 patients with curatively resected GC, including cancers of the esophagogastric junction Siewert type II and III, were identified in the German centers of the staR consortium. Tumor sections were assessed for expression of MLH1, MSH2, MSH6 and PMS2 by immunohistochemistry. The association between MMR status and survival was assessed. Similar studies published up to January 2021 were then identified in a MEDLINE search for a meta-analysis.

RESULTS

MMR-status and survival data were available for 223 patients (median age 66 years, 62.8% male), 23 patients were MMRd (10.3%). After matching for baseline clinical characteristics, median OS was not reached in any subgroup. Compared to perioperative chemotherapy, patients receiving surgery alone with MMRd and MMRp had a HR of 0.67 (95% CI 0.13-3.37, P = 0.63) and 1.44 (95% CI 0.66-3.13, P = 0.36), respectively. The meta-analysis included pooled data from 385 patients. Compared to perioperative chemotherapy, patients receiving surgery alone with MMRd had an improved OS with a HR of 0.36 (95% CI 0.14-0.91, P = 0.03), whereas those with MMRp had a HR of 1.18 (95% CI 0.89-1.58, P = 0.26).

CONCLUSION

Our data support a positive prognostic effect for MMRd in GC patients treated with surgery only and a differentially negative prognostic effect in patients treated with perioperative chemotherapy. MMR status determined by preoperative biopsies may be used as a predictive biomarker to select patients for perioperative chemotherapy in curatively resectable GC.

Targeting the gut microbiome in the management of sepsis-associated encephalopathy

Brain injury resulting from sepsis, or sepsis-associated encephalopathy (SAE), occurs due to impaired end-organ perfusion, dysregulated inflammation affecting the central nervous system (CNS), blood-brain barrier (BBB) disruption, mitochondrial dysfunction, oxidative stress, accumulation of toxic neuropeptides and impaired toxin clearance secondary to sepsis-induced hepatic and renal dysfunction. The gut microbiome becomes pathologically altered in sepsis, which likely contributes to the pathogenesis of SAE. Herein, we review the literature detailing dysregulation of microbiota-gut-brain axis (MGBA) in SAE and highlight potential therapeutic strategies to modulate the gut microbiome to mitigate sepsis-induced brain injury.

5-Fluorouracil Neurotoxicity in the Absence of Dihydropyrimidine Dehydrogenase Deficiency Case Report

5 fluorouracil (5-FU)-related neurotoxicity is a rare and severe complication of 5-FU administration. Dihydropyrimidine dehydrogenase (DPD) deficiency is associated with an increased risk of serious adverse reactions due to its role in 5-FU metabolism. We report a case of acute reversible neurotoxicity with global areas of diffusion restriction in a patient with colorectal adenocarcinoma being treated with leucovorin calcium, 5-fluorouracil, and oxaliplatin (FOLFOX) without DPD deficiency following uridine triacetate administration.

[Update on collaborative autopsy-based research in German pathology, neuropathology, and forensic medicine]

BACKGROUND

Autopsies are a valuable tool for understanding disease, including COVID-19.

MATERIALS AND METHODS

The German Registry of COVID-19 Autopsies (DeRegCOVID), established in April 2020, serves as the electronic backbone of the National Autopsy Network (NATON), launched in early 2022 following DEFEAT PANDEMIcs.

RESULTS

The NATON consortium's interconnected, collaborative autopsy research is enabled by an unprecedented collaboration of 138 individuals at more than 35 German university and non-university autopsy centers through which pathology, neuropathology, and forensic medicine autopsy data including data on biomaterials are collected in DeRegCOVID and tissue-based research and methods development are conducted. More than 145 publications have now emerged from participating autopsy centers, highlighting various basic science and clinical aspects of COVID-19, such as thromboembolic events, organ tropism, SARS-CoV‑2 detection methods, and infectivity of SARS-CoV-2 at autopsy.

CONCLUSIONS

Participating centers have demonstrated the high value of autopsy and autopsy-derived data and biomaterials to modern medicine. The planned long-term continuation and further development of the registry and network, as well as the open and participatory design, will allow the involvement of all interested partners.

Vitamin B12 and gut-brain homeostasis in the pathophysiology of ischemic stroke

Stroke is a leading cause of morbidity and mortality worldwide. It inflicts immeasurable suffering on patients and their loved ones and carries an immense social cost. Efforts to mitigate the impact of stroke have focused on identifying therapeutic targets for the prevention and treatment. The gut microbiome represents one such potential target given its multifaceted effects on conditions known to cause and worsen the severity of stroke. Vitamin B12 (VB12) serves as a cofactor for two enzymes, methylmalonyl-CoA synthase and methionine synthase, vital for methionine and nucleotide biosynthesis. VB12 deficiency results in a buildup of metabolic substrates, such as homocysteine, that alter immune homeostasis and contribute to atherosclerotic disorders, including ischemic stroke. In addition to its support of cellular function, VB12 serves as a metabolic cofactor for gut microbes. By shaping microbial communities, VB12 further impacts local and peripheral immunity. Growing evidence suggests that gut dysbiosis-related immune dysfunction induced by VB12 deficiency may potentially contributes to stroke pathogenesis, its severity, and patient outcomes. In this review, we discuss the complex interactions of VB12, gut microbes and the associated metabolites, and immune homeostasis throughout the natural history of ischemic stroke.

Deep learning for diagnosis and survival prediction in soft tissue sarcoma

BACKGROUND

Clinical management of soft tissue sarcoma (STS) is particularly challenging. Here, we used digital pathology and deep learning (DL) for diagnosis and prognosis prediction of STS.

PATIENTS AND METHODS

Our retrospective, multicenter study included a total of 506 histopathological slides from 291 patients with STS. The Cancer Genome Atlas cohort (240 patients) served as training and validation set. A second, multicenter cohort (51 patients) served as an additional test set. The use of the DL model (DLM) as a clinical decision support system was evaluated by nine pathologists with different levels of expertise. For prognosis prediction, 139 slides from 85 patients with leiomyosarcoma (LMS) were used. Area under the receiver operating characteristic (AUROC) and accuracy served as main outcome measures.

RESULTS

The DLM achieved a mean AUROC of 0.97 (±0.01) and an accuracy of 79.9% (±6.1%) in diagnosing the five most common STS subtypes. The DLM significantly improved the accuracy of the pathologists from 46.3% (±15.5%) to 87.1% (±11.1%). Furthermore, they were significantly faster and more certain in their diagnosis. In LMS, the mean AUROC in predicting the disease-specific survival status was 0.91 (±0.1) and the accuracy was 88.9% (±9.9%). Cox regression showed the DLM's prediction to be a significant independent prognostic factor (P = 0.008, hazard ratio 5.5, 95% confidence interval 1.56-19.7) in these patients, outperforming other risk factors.

CONCLUSIONS

DL can be used to accurately diagnose frequent subtypes of STS from conventional histopathological slides. It might be used for prognosis prediction in LMS, the most prevalent STS subtype in our cohort. It can also help pathologists to make faster and more accurate diagnoses. This could substantially improve the clinical management of STS patients.

Hematoma expansion is more frequent in deep than lobar intracerebral hemorrhage

OBJECTIVE

To test the hypothesis that patients with deep intracerebral hemorrhage (ICH) would encounter hematoma expansion (HE) more frequently compared to patients with lobar ICH.

METHODS

Patients with ICH with neuroimaging to calculate HE were analyzed from the multicenter Ethnic/Racial Variations of Intracerebral Hemorrhage (ERICH) cohort. Patients with laboratory coagulopathy or preceding anticoagulant use were excluded to assess relationships of ICH location alone (deep vs lobar) with HE, defined as >33% relative growth. Odds ratios (ORs) and 95% confidence intervals (CIs) for these relationships were estimated with logistic regression. Sensitivity and specificity determined HE thresholds best associated with poor 3-month outcomes (modified Rankin score 4-6) stratified by location.

RESULTS

There were 1,049 patients with deep and 408 patients with lobar ICH analyzed. Deep ICH locations were more likely to have HE (adjusted OR 1.57, 95% CI 1.08-2.29) after adjustment for age, sex, race, baseline hematoma size, and intraventricular hemorrhage. However, this difference was nonsignificant (adjusted OR 1.35, 95% CI 0.81-2.24) after controlling for time from symptom onset to admission CT in a subgroup analysis of 729 patients with these data. Yet, the threshold of HE best associated with poor outcomes was smaller in deep (30%) compared to lobar (50%) ICH.

CONCLUSIONS

While HE was more frequent in deep than lobar ICH, this could be due to differences in symptom onset to admission CT times in our cohort. However, patients with deep ICH appear particularly vulnerable to the deleterious effects of small volumes of HE. Further studies should clarify whether ICH location needs to be considered in HE treatment paradigms.

Neuronophagia and microglial nodules in a SARS-CoV-2 patient with cerebellar hemorrhage

We document the neuropathologic findings of a 73-year old man who died from acute cerebellar hemorrhage in the context of relatively mild SARS-CoV2 infection. The patient developed sudden onset of headache, nausea, and vomiting, immediately followed by loss of consciousness on the day of admission. Emergency medical services found him severely hypoxemic at home, and the patient suffered a cardiac arrest during transport to the emergency department. The emergency team achieved return of spontaneous circulation after over 17 min of resuscitation. A chest radiograph revealed hazy bilateral opacities; and real-time-PCR for SARS-CoV-2 on the nasopharyngeal swab was positive. Computed tomography of the head showed a large right cerebellar hemorrhage, with tonsillar herniation and intraventricular hemorrhage. One day after presentation, he was transitioned to comfort care and died shortly after palliative extubation. Autopsy performed 3 h after death showed cerebellar hemorrhage and acute infarcts in the dorsal pons and medulla. Remarkably, there were microglial nodules and neuronophagia bilaterally in the inferior olives and multifocally in the cerebellar dentate nuclei. This constellation of findings has not been reported thus far in the context of SARS-CoV-2 infection.

PARE0007 PATIENT AND PUBLIC INVOLVEMENT IN CLINICAL TRIAL DESIGN

Background:

Patient and public involvement (PPI) is gaining increasing recognition as important in ensuring research is relevant and acceptable to participants. Rheuma Tolerance for Cure (RTCure) is a 5 year international collaboration between academia and industry; focusing on earlier detection and prevention of rheumatoid arthritis (RA) through the use of immune-tolerising treatments.

Objectives:

To bring lived experience and insight into scientific discussions; and to evolve collaboration between lay representatives and academia/industry.

Methods:

9 Patient Research Partners (PRPs) from 5 European countries were recruited via the EULAR PARE Network and institutions within the RTCure Consortium (8 PRPs with RA and 1 ‘at risk’). They were asked to enter into a legal agreement with the Consortium. PRPs participated in teleconferences (TCs) and were invited to attend face-to-face (F2F) meetings at least annually. Requests for input/feedback were sent from researchers to PRPs via the project’s Patient Engagement Expert [SK].

Results:

PRP involvement has given researchers and industry partners a new perspective on patient priorities, and focused thought on the ethics of recruitment for and participation in clinical trials of people ‘at risk’ of developing RA. PRPs have helped define the target populations, given their thoughts on what types of treatments are acceptable to people ‘at risk’ and have aided the development of a survey (sent to EULAR PARE members) regarding the use of animal models in biomedical research. Positive informal feedback has been received from researchers and industry regarding the contribution of PRPs to the ongoing project (formal evaluation of PPI in RTCure will be carried out in 2020 and at the project end in 2022).

Challenges:

Legal agreements- Many PRPs refused to sign the Consortium’s complex PRP Agreement; feeling it unnecessary, incomprehensible and inequitable. After extensive consultation with various parties (including EULAR and the Innovative Medicines Initiative) no similar contract was found. Views for its requirement even varied between legal experts. After 2 years of intense discussion, a simple non-disclosure agreement was agreed upon. Ideally any contract, if required, should be approved prior to project onset.

Meeting logistics- Other improvements identified were to locate the meeting venue and accommodation on the same site to minimise travel, and to make it easier for PRPs to take breaks when required. This also facilitates informal discussions and patient inclusivity. We now have agreed a policy to fund PRPs extra nights before and after meetings, and to bring a carer if needed.

Enabling understanding– Future annual meetings will start with a F2F meeting between PRPs and Work Package Leads. Researchers will be encouraged to start presentations with a summary slide in lay language. Additionally, an RTCure Glossary is in development.

Enabling participation– SK will provide monthly project updates and PRP TCs will be held in the evening (as some PRPs remain employed). PRPs will be invited to all project TCs and F2F meetings. Recruitment is underway to increase the number of ‘at risk’ PRPs as their viewpoint is vital to this study.

Conclusion:

Currently PPI in RTCure is an ongoing mutual learning process. Universal guidance regarding what types of contracts are needed for PPI would be useful. Communication, trust and fruitful discussions have evolved through F2F meetings (both formal and informal) between PRPs, academia and industry. It is important that all parties can be open with each other in order to make PPI more meaningful.

Acknowledgments:

This work has received support from the EU/EFPIA Innovative Medicines Initiative 2 Joint Undertaking RTCure grant number 777357.

Disclosure of Interests:

Savia de Souza: None declared, Ruth Williams: None declared, Eva Johansson: None declared, Codruta Zabalan: None declared, Tom Esterine: None declared, Margôt Bakkers: None declared, Wolfgang Roth: None declared, Neil Mc Carthy: None declared, Meryll Blake: None declared, Susanne Karlfeldt: None declared, Martina Johannesson: None declared, Karim Raza Grant/research support from: KR has received research funding from AbbVie and Pfizer, Consultant of: KR has received honoraria and/or consultancy fees from AbbVie, Sanofi, Lilly, Bristol-Myers Squibb, UCB, Pfizer, Janssen and Roche Chugai, Speakers bureau: KR has received honoraria and/or consultancy fees from AbbVie, Sanofi, Lilly, Bristol-Myers Squibb, UCB, Pfizer, Janssen and Roche Chugai

Long-Term Efficacy and Safety of Superficial Radiation Therapy in Subjects With Nonmelanoma Skin Cancer: A Retrospective Registry Study

Background: Low-dose superficial radiation therapy (SRT) effectively treats nonmelanoma skin cancer (NMSC) without requiring invasive excision. SRT is especially safe and effective among the elderly who comprise most patients with basal cell and squamous cell carcinomas (BCCs and SCCs). Objective: To demonstrate the long-term safety and efficacy of SRT for treating NMSC with a new generation device. Methods: A retrospective chart review was performed at four clinical study sites. The study population included male and female patients (N=516) treated with SRT for NMSC (N=776) including BCCs (n=448) and SCCs (n=328) prior to January 2015 with long-term follow-up records. Results: The overall mean (SD) total treatment dosage was 4652.33 (366.34) cGy (range, 3636.6 to 5455 cGy) administered over a mean of 12.3 (1.85) sessions. The overall Kaplan-Meier survival probability estimate (95% CI) was 0.989 (0.980, 0.998) at 24 months, 0.989 (0.969, 1.000) at 60 months, and 0.989 (0.942, 1.000) at 85 months. There were six recurrences of BCCs (n=4) and SCCs (n=2). The most common adverse event was hypopigmentation. Limitations: Retrospective study design and some incomplete data. Conclusion: It is estimated that 98.9% of nonmelanoma skin cancers will not recur after 85 months following superficial radiation therapy. J Drugs Dermatol. 2020;19(2)163-168. doi:10.36849/JDD.2020.4647

[Liquid biopsy in colorectal cancer : An overview of ctDNA analysis in tumour diagnostics]

In current routine diagnostics, the gold standard to determine the genomic profile of colorectal cancers (CRCs) is using biopsy or surgically resected tissues. However, such a tissue sample cannot represent the entire tumour heterogeneity, because it only shows a local and temporal snapshot. As a complement to tumour tissue genotyping, liquid biopsies enable minimally invasive detection of all potential tumour-specific mutations and their dynamic changes for molecular profiling. Furthermore, they can be repeated in certain intervals for monitoring response to treatment, occurrence of drug resistance and detection of relapse. This review focusses on analyzing circulating cell-free tumour DNA (ctDNA), which is mostly released from apoptotic or necrotic tumour cells into the bloodstream or by active secretion of circulating tumour cells (CTCs). Nevertheless, there are some challenges in analyzing ctDNA. First, ctDNA represents only a small fraction of total circulating DNA, because there is an enormous wild-type background of cell-free DNA (cfDNA) released by healthy cells. Second, ctDNA is highly fragmented and the amount of ctDNA in the blood is very low. In this review, we discuss the potential, fields of application as well as challenges and limitations of liquid biopsy approaches. In more detail, we discuss the possibility of using liquid biopsies as a future application for molecular characterization of CRCs, particularly for monitoring CRC patients during anti-EGFR therapy to detect resistance mutations (e.g. KRAS mutations) or further therapy-relevant mutations. In addition, we investigate whether blood-based molecular profiling is a reliable addition to routine diagnostic approaches of tissue-based molecular characterization.

[Status of the availability and use of next generation sequencing (NGS) in bladder cancer-a questionnaire within the uropathology working group]

BACKGROUND

Technical advancement and availability of high-throughput analysis has advanced molecular subtyping of most cancers. Thus, new possibilities for precision oncology have emerged.

AIM

Therefore, we aimed to collect data regarding availability and use of next generation sequencing (NGS) for urothelial cancer within the uropathology working group of the German Society of Pathology.

METHODS

We collected data by questionnaires and additionally asked for sequencing results of bladder cancers in the participating institutions.

RESULTS

A total of 13 university-affiliated institutes of pathology took part in the survey. All university institutes offer NGS-based molecular panel diagnostics and provide panels covering between 15 and 170 genes. Altogether, only 20 bladder cancers were sequenced in routine diagnostics and for 10 cancers potential targeted treatment options were available.

DISCUSSION

So far, despite availability of NGS diagnostics at university institutes of pathology, only few bladder cancer samples have been sequenced. Based on current data from the molecular subtyping of bladder cancers, we recommend a step-by-step protocol with basic immunohistochemistry analysis and subsequent subtype-dependent analyses, e.g., alterations of the fibroblast growth factor receptors (FGFR) or comprehensive gene panel analyses.

[Prognostic significance of immune cell infiltrates in tumor pathology]

BACKGROUND

The quantity, distribution, activation status, cytokine profile, and spatial distribution of tumor-infiltrating immune cells have prognostic value and may be predictive of response to immunotherapies.

OBJECTIVES

A survey of relevant immune cell populations including their prognostic significance in the most common types of tumors.

METHODS

Nonsystematic assessment and a discussion of studies that were conducted to estimate the prognostic significance of certain immune cell subsets and the methodical approaches used.

RESULTS

For many tumor entities, prognostically favorable and unfavorable immune cell populations can be differentiated. However, nonspecific cell markers that may partly summarize antithetic immune cell subsets can be employed. Differences in sampling procedures and the determination of cut-off levels further limit the comparability of the studies carried out so far.

CONCLUSION

The phenotypic and functional heterogeneity of tumor-infiltrating immune cells requires the use of cell subset-specific antibodies and antibody combinations. Furthermore, harmonized assessment routines, validation studies, and meta-analyses are important prerequisites for potential diagnostic implementation.

Consensus Guidelines on the Use of Superficial Radiation Therapy for Treating Nonmelanoma Skin Cancers and Keloids

Background: The use of superficial radiation therapy (SRT) has experienced a renaissance for treating nonmelanoma skin cancers (NMSCs) and recurrent keloids; however, published treatment guidelines are lacking. Objective: The objective of this work was to provide consensus guidelines on the use of SRT for treating NMSC and recurrent keloids based on a review of the literature and expert opinion. Methods and Materials: A search of the medical literature was performed to obtain published information on the use of SRT for review. A group of qualified dermatologists convened to discuss their views on the use of SRT for the treatment of NMSCs and recurrent keloids. The various guidelines were considered to have consensus based on a supermajority two-thirds vote. The final consensus guidelines are thus based on the medical literature, when available, and expert opinions. Results: Agreement on consensus guidelines was reached for numerous aspects of SRT use, including appropriate tumor types for SRT; anatomical areas suitable for SRT; energy, fractions, and scheduling recommendations for SRT; use of SRT in the presence of comorbidities; safety factors; and treatment recommendations for recurrent keloids, based the literature and on both the opinions of the expert group and a survey of experienced users. Conclusion: Consensus was reached that SRT is a safe and effective treatment for basal cell and squamous cell carcinomas and should be considered as the first-line form of radiation treatment. Postsurgical treatment of keloid excision suture lines with SRT significantly reduces keloid recurrence rates.

Abstract A42: Identifying relationships between high expression levels of the HSPA9 gene, putative HSPA9 alterations, and patient survivability in invasive breast carcinomas

Metastasis is the primary cause for the lethality of breast cancer, and is responsible for approximately 90% of breast cancer-related deaths. Tumor cell resistance to cancer treatment continues to stymie efforts to effectively treat breast cancer, which we know to be primarily mediated by a highly conserved molecular chaperone in the heat shock protein 70 family known as mortalin. Mortalin is encoded by the gene HSPA9B localized on chromosome 5q31.1.1, and is low or undetectable in normal unstressed cells while highly expressed in many carcinomas. Breast cancer cell invasion and metastasis are closely related to adverse clinical outcomes and a worsened prognosis for patients. Previous studies have shown that breast cancer patients with high mortalin expression had decreased DFS and OS rates compared to those with low mortalin expression in early- or late-stage breast cancer. Conversely, low expression of mortalin decreases tumor cell progression and inhibits the epithelial-mesenchymal transition. Gene amplification is one of the major pathways by which proto-oncogenes are activated during tumorigenesis, and missense mutations in the gene of interest could potentially render a nonfunctional mortalin product. We examined three different publicly available datasets from the Genome Data Commons for possible relationships between alterations in the HSPA9 gene and BRCA patient survival rates. On a mutation-specific level, we compared the survival rates of the cases with a high frequency of HSPA9 alterations versus the cases without HSPA9 alterations. Our bioinformatics analysis of the BRCA datasets showed fourteen alterations in the HSPA9 gene that correlated to prognosis and survival rate in patients with breast cancer. Amplifications in the HSPA9 gene lead to lower survivability rates for the patient samples, while missense mutations in HSPA9 led to higher survivability rates. Also of interest, missense mutations were far more numerous than any other HSPA9 alteration type. Different alterations in the HSPA9 gene result in different mortalin protein products, ultimately leading to differences in prognosis for patients with invasive breast carcinomas. Our study supports that much of the clinically observable plasticity and heterogeneity occurs within, rather than across, the major biologic subtypes of breast cancer suggested by the variance in HSPA9 alteration types. Furthermore, the study supports that mortalin expression has a significant effect on breast cancer status and lends credence to mortalin as a survival predictor, particularly in BRCA patients.

Note: This abstract was not presented at the conference.

Citation Format: Kofi K. Khamit-Kush, James W. Lillard, Jr., Vincent C. Bond, Ming Huang, William Roth. Identifying relationships between high expression levels of the HSPA9 gene, putative HSPA9 alterations, and patient survivability in invasive breast carcinomas [abstract]. In: Proceedings of the AACR Special Conference: Advances in Breast Cancer Research; 2017 Oct 7-10; Hollywood, CA. Philadelphia (PA): AACR; Mol Cancer Res 2018;16(8_Suppl):Abstract nr A42.

Therapy susceptible germline-related BRCA 1-mutation in a case of metastasized mixed adeno-neuroendocrine carcinoma (MANEC) of the small bowel

Background

Adenocarcinomas or combined adeno-neuroendocrine carcinomas (MANEC) of small bowel usually have a dismal prognosis with limited systemic therapy options. This is the first description of a patient showing a germline-related BRCA1 mutated MANEC of his ileum. The tumor presented a susceptibility to a combined chemotherapy and the PARP1-inhibitor olaparib.

Case presentation

A 74-year old male patient presented with a metastasized MANEC of his ileum. Due to clinical symptoms his ileum-tumor and the single brain metastasis were removed. We verified the same pathogenic (class 5) BRCA1 mutation in different tumor locations. There was no known personal history of a previous malignant tumor. Nevertheless we identified his BRCA1 mutation as germline-related. A systemic treatment was started including Gemcitabine followed by selective internal radiotherapy (SIRT) to treat liver metastases and in the further course Capecitabine but this treatment finally failed after 9 months and all liver metastases showed progression. The treatment failure was the reason to induce an individualized therapeutic approach using combined chemotherapy of carboplatin, paclitaxel and the Poly (ADP-ribose) polymerase- (PARP)-inhibitor olaparib analogous to the treatment protocol of Oza et al.

All liver metastases demonstrated with significant tumor regression after 3 months and could be removed. In his most current follow up from December 2017 (25 months after his primary diagnosis) the patient is in a very good general condition without evidence for further metastases.

Conclusion

We present first evidence of a therapy susceptible germline-related BRCA1 mutation in small bowel adeno-neuroendocrine carcinoma (MANEC). Our findings offer a personalized treatment option. The germline background was unexpected in a 74-year old man with no previously known tumor burden. We should be aware of the familiar background in tumors of older patients as well.

Early myoclonus following anoxic brain injury

Background

It is unknown whether postanoxic cortical and subcortical myoclonus are distinct entities with different prognoses.

Methods

In this retrospective cohort study of 604 adult survivors of cardiac arrest over 8.5 years, we identified 111 (18%) patients with myoclonus. Basic demographics and clinical characteristics of myoclonus were collected. EEG reports, and, when available, raw video EEG, were reviewed, and all findings adjudicated by 3 authors blinded to outcomes. Myoclonus was classified as cortical if there was a preceding, time-locked electrographic correlate and otherwise as subcortical. Outcome at discharge was determined using Cerebral Performance Category.

Results

Patients with myoclonus had longer arrests with less favorable characteristics compared to patients without myoclonus. Cortical myoclonus occurred twice as often as subcortical myoclonus (59% vs 23%, respectively). Clinical characteristics during hospitalization did not distinguish the two. Rates of electrographic seizures were higher in patients with cortical myoclonus (43%, vs 8% with subcortical). Survival to discharge was worse for patients with myoclonus compared to those without (26% vs 39%, respectively), but did not differ between subcortical and cortical myoclonus (24% and 26%, respectively). Patients with cortical myoclonus were more likely to be discharged in a comatose state than those with subcortical myoclonus (82% vs 33%, respectively). Among survivors, good functional outcome at discharge was equally possible between those with cortical and subcortical myoclonus (12% and 16%, respectively).

Conclusions

Cortical and subcortical myoclonus are seen in every sixth patient with cardiac arrest and cannot be distinguished using clinical criteria. Either condition may have good functional outcomes.

Determinants of Long-Term Neurological Recovery Patterns Relative to Hospital Discharge Among Cardiac Arrest Survivors

OBJECTIVE

To explore factors associated with neurological recovery at 1 year relative to hospital discharge after cardiac arrest.

DESIGN

Observational, retrospective review of a prospectively collected cohort.

SETTING

Medical or surgical ICUs in a single tertiary care center.

PATIENTS

Older than 18 years, resuscitated following either in-hospital or out-of-hospital cardiac arrest and considered for targeted temperature management between 2007 and 2013.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Logistic regressions to determine factors associated with a poor recovery pattern after 1 year, defined as persistent Cerebral Performance Category Score 3-4 or any worsening of Cerebral Performance Category Score relative to discharge status. In total, 30% (117/385) of patients survived to hospital discharge; among those discharged with Cerebral Performance Category Score 1, 2, 3, and 4, good recovery pattern was seen in 54.5%, 48.4%, 39.5%, and 0%, respectively. Significant variables showing trends in associations with a poor recovery pattern (62.5%) in a multivariate model were age more than 70 years (odds ratio, 4; 95% CIs, 1.1-15; p = 0.04), Hispanic ethnicity (odds ratio, 4; CI, 1.2-13; p = 0.02), and discharge disposition (home needing out-patient services (odds ratio, 1), home requiring no additional services (odds ratio, 0.15; CI, 0.03-0.8; p = 0.02), acute rehabilitation (odds ratio, 0.23; CI, 0.06-0.9; p = 0.04).

CONCLUSIONS

Patients discharged with mild or moderate cerebral dysfunction sustained their risk of neurological worsening within 1 year of cardiac arrest. Old age, Hispanic ethnicity, and discharge disposition of home with out-patient services may be associated with a poor 1 year neurological recovery pattern after hospital discharge from cardiac arrest.

Cerebral Ischemic Reperfusion Injury Following Recanalization of Large Vessel Occlusions

Although stroke has recently dropped to become the nation's fifth leading cause of mortality, it remains the top leading cause of morbidity and disability in the US. Recent advances in stroke treatment, including intravenous fibrinolysis and mechanical thromboembolectomy, allow treatment of a greater proportion of stroke patients than ever before. While intra-arterial fibrinolysis with recombinant tissue plasminogen is an effective for treatment of a broad range of acute ischemic strokes, endovascular mechanical thromboembolectomy procedures treat severe strokes due to large artery occlusions, often resistant to intravenous drug. Together, these procedures result in a greater proportion of revascularized stroke patients than ever before, up to 88% in 1 recent trial (EXTEND-IA). Subsequently, there is a growing need for neurointensivists to develop more effective strategies to manage stroke patients following successful reperfusion. Cerebral ischemic reperfusion injury (CIRI) is defined as deterioration of brain tissue suffered from ischemia that concomitantly reverses the benefits of re-establishing cerebral blood flow following mechanical or chemical therapies for acute ischemic stroke. Herein, we examine the pathophysiology of CIRI, imaging modalities, and potential neuroprotective strategies. Additionally, we sought to lay down a potential treatment approach for patients with CIRI following emergent endovascular recanalization for acute ischemic stroke.

Renal tubular epithelial cell-derived BAFF expression mediates kidney damage and correlates with activity of proliferative lupus nephritis in mouse and men

B-cell activating factor of the tumour necrosis factor family (BAFF) is a cytokine, mainly produced by hematopoietic cells (e.g. monocytes/macrophages, dendritic cells), indispensable for B-cell maturation. The BLISS studies have demonstrated that blocking BAFF by the human monoclonal antibody belimumab is a valuable therapeutic approach in patients with clinically and serologically active systemic lupus erythematosus (SLE). However, the defined sources of BAFF, which contributes to SLE, are still unclear. Recent findings show that BAFF expression is not restricted to myeloid cells. Since lupus nephritis is the main cause of morbidity and mortality for SLE patients, the aim of this study was to investigate whether renal tubular epithelial cells (TEC) are an important source of BAFF and thus may contribute to the pathogenesis and progression of SLE. We found BAFF expression both in cultured murine and human TEC. These results could be verified with in situ data from the kidney. Moreover, BAFF expression in the kidneys of lupus-prone MRL- Fas^lpr mice correlated with disease activity, and BAFF expression on TEC in biopsies of patients with diffuse proliferative lupus nephritis showed a correlation with the histopathological activity index. In vitro functional assays revealed an autocrine loop of BAFF with its binding receptors on TEC, resulting in a strong induction of colony stimulating factor-1. Finally, we identified divergent effects of BAFF on TEC depending on the surrounding milieu ('inflammatory versus non-inflammatory'). Taken together, our findings indicate that renal-derived BAFF may play an important role in the pathophysiology of the systemic autoimmune disease SLE.

Immaturity for gestational age of microvasculature and placental barrier in term placentas with high weight

OBJECTIVE

Villous immaturity for gestational age is a multifactorial developmental deviation associated with unexpected placental insufficiency, fetal hypoxia and term fetal death. In our previous work we have shown that immature CD15+/CD31+/CD34+ endothelial cells were an important indicator of placental villous immaturity and chronic insufficiency. The aim of this study was to perform a comparative analysis of CD15-marked immaturity in the vessel walls between normal and pathological term placentas of clinically and structurally heterogenous groups with normal, low and high weight.

STUDY DESIGN

165 clinically normal and pathological placentas of gestational age 39-42 with normal weight (25-75 percentile), low weight (<10 percentile) and high weight (>90 percentile) were structurally and immunohistochemically analyzed. Excluded were placentas with a severe form of placental insufficiency associated with intrauterine fetal death, low APGAR-score, genetic and chromosomal diseases or placental inflammations. The distribution patterns of CD15, CD31 and CD34 were assessed separately in the macrovasculature, microvasculature and placental barrier (PB) - associated capillaries.

RESULTS

All placental groups with normal weight, low weight and high weight include normal, accelerated villous maturation or villous immaturity independent of their weight. However, a significant increase of immature CD15+/CD31+/CD34+ endothelial cells was detected in microvasculature and PB -associated capillaries in high weight-placentas (63.5%/52.2%), compared to those of normal weight (13.8%/8.2%) and low weight (16.1%/17.8%). The distribution of macrovascular immature CD15+/CD31+/CD34+ endothelial cells did not show such marked differences.

CONCLUSION

We have identified the immaturity of microvasculature and PB -associated capillaries with a pathological persistency of immature CD15+/CD31+/CD34+ endothelial cells and a reduction of terminally differentiated CD15-/CD31+/CD34+ endothelial cells in a structurally and clinically heterogeneous group of high weight-placentas. We assume that immaturity of placental vessels are part of prenatal adaptational processes that can be recruited in different emergency situations and may provide potential targets of therapeutic correction of placental growth and chronic insufficiency. We therefore recommend the use of CD15-based immunophenotyping as a method to identify latent unfavorable conditions of fetal development in the intrauterine life and individual risk of disease in the postnatal period.

[Multiparametric MRI and MRI-TRUS fusion biopsy in patients with prior negative prostate biopsy]

BACKGROUND

Multiparametric MRI (mpMRI) plays an increasingly important role in prostate cancer (PCa) diagnostics and is recommended in men with previously negative TRUS biopsy. The optimal biopsy method after mpMRI is under discussion.

OBJECTIVE

Prospective, PIRADS- and START-conform analysis of the relevance of mpMRI and MRI-TRUS fusion biopsy in patients with prior negative TRUS biopsy and comparison of the detection rates of fusion-targeted biopsies (tB) and systematic transperineal saturation biopsies (sB).

MATERIALS AND METHODS

Between 10/2012 and 09/2015, 287 patients with prior negative TRUS biopsy underwent mpMRI and software-assisted, rigid MRI-TRUS fusion biopsy. In addition to and strictly separated from sB (median cores n = 24), tB (median cores per patient n = 4, per lesion n = 3) were performed in case of suspicious MRI lesions (PIRADS ≥ 2). Both biopsy methods were compared by using McNemar's test.

RESULTS

Of the 287 patients, 148 (52 %) had positive biopsies. Of these, 108/287 (38 %) had significant PCa (Gleason Score [GS] = 3 + 3 and PSA ≥ 10 ng/ml or GS ≥ 3 + 4) and again 43/287 (15 %) had a GS ≥ 4 + 3 PCa. sB failed to diagnose 8/148 PCa (5.4 %) and 6/108 significant PCa (5.5 %), whereas tB failed to diagnose 48 (32.4 %) PCa (p < 0.0001) and 22 (20.4 %) significant PCa (p = 0.0046). Of the PCa missed by tB, 11  had a GS ≥ 3 + 4 and 5 of these a GS = 4 + 3. On a per patient basis, MRI failed to detect 5 significant PCa, whereby 17 of the significant PCa were missed by fusion-targeted cores alone.

CONCLUSIONS

In men with unsuspicious MRI (PIRADS < 3), there is a 11 % risk of significant PCa. In case of suspicious MRI lesions, the combination of both biopsy approaches offers maximum tumor detection.

Anchoring Pipeline Flow Diverter Construct in the Treatment of Traumatic Distal Cervical Carotid Artery Injury

Background

Traumatic extracranial internal carotid artery (ICA) dissections are uncommon and can be difficult to treat. Thinning of adventitia and dilatation may occur following arterial dissection, thus resulting in a fusiform pseudoaneurysm, which can subsequently cause bleeding, expanding, or pulsatile hematoma. Currently, medical management with anticoagulation remains the first line of treatment and yields good outcomes in 75% of cases with a mortality rate of 3-4%. Endovascular intervention is indicated with failure of medical therapy, progressive enlargement of a traumatic pseudoaneurysm, acute flow-related infarcts due to vessel occlusion, or when anticoagulation is contraindicated due to risk of pseudoaneurysm rupture and hemorrhage. Recognized interventional treatments include parent artery occlusion with or without revascularization, endovascular coil embolization, and covered stenting.

Summary

A wide variety of endovascular stents are available that are capable of opening a stenosed vessel while obliterating the associated false lumen and providing a scaffold for embolization of the pseudoaneurysm. The use of the Pipeline Embolization Device (PED) in the management of traumatic intracranial pseudoaneurysms has been described. However, there are few reports on the usage of the PED for treating traumatic extracranial ICA dissection and/or pseudoaneurysms. However, a potential complication of the use of PED in the extracranial ICA is a hypothetical tendency to migrate in a mobile vessel. Thus, the risk of migration of the PED has encouraged practitioners to adopt strategies to limit this risk.

Key Messages

We describe different techniques employed to anchor the flow-diverting construct within tortuous, mobile vessels.

Histopathological Differences Between the Anterior and Posterior Brain Arteries as a Function of Aging

BACKGROUND AND PURPOSE

We tested the hypothesis that posterior brain arteries differ pathologically from anterior brain arteries and that this difference varies with age.

METHODS

Brain large arteries from 194 autopsied individuals (mean age 56±17 years, 63% men, 25% nonwhite, 17% with brain infarcts) were analyzed to obtain the areas of arterial layers and lumen as well as the relative content of elastin, collagen, and amyloid. Visual rating was used to determine the prevalence of atheroma, calcification, vasa vasorum, pattern of intima thickening, and internal elastic lamina gaps. We used multilevel models adjusting for age, sex, ethnicity, vascular risk factors, artery type and location, and multiple comparisons.

RESULTS

Of 1362 large artery segments, 5% had vasa vasorum, 5% had calcifications, 15% had concentric intimal thickening, and 11% had atheromas. Posterior brain arteries had thinner walls, less elastin, and more concentric intima thickening than anterior brain arteries. Compared to anterior brain arteries, the basilar artery had higher arterial area encircled by the internal elastic lamina, whereas the vertebral arteries had higher prevalence of elastin loss, concentric intima thickening, and nonatherosclerotic stenosis. In younger individuals, vertebral artery calcifications were more likely than calcification in anterior brain arteries, but this difference attenuated with age.

CONCLUSIONS

Posterior brain arteries differ pathologically from anterior brain arteries in the degree of wall thickening, elastin loss, and concentric intimal thickening.

[Cell death in malignant tumors. Relevance of cell death regulation for metastasis]

Defects in the regulation of cell death are important causes for both the development and therapy resistance of malignant tumors. Several distinct, molecularly defined types of cell death are known, such as apoptosis, anoikis, and necroptosis. Moreover, the specific triggering of cell death plays an important role in the prevention of metastasis. The results of recent studies have shown that various types of cell death are pivotal at different steps of the metastasis cascade, in order to prevent cellular detachment, migration, invasion, intravasation, extravasation and the establishment of micrometastasis and macrometastasis. At the subcellular level, numerous links exist between cell death regulation and metastasis, specifically regarding signaling pathways and individual proteins with dual or multiple functions. As an example, the decoy receptor 3 protein (DcR3) functions both as an anti-apoptotic protein and as a direct promotor of invasion and migration of tumor cells. In summary, the specific triggering of cell death plays a pivotal role for the prevention of metastasis. On the other hand, the stepwise process of metastasis represents a mechanism of selection resulting in established metastases with a multiresistant phenotype which corresponds to the clinical observation that many metastasized cancers are therapy resistant. In the future, innovative diagnostic tests to individually predict the resistance pattern and possibilities to overcome resistance are urgently needed.

Use of Intra-aortic- Balloon Pump Counterpulsation in Patients with Symptomatic Vasospasm Following Subarachnoid Hemorrhage and Neurogenic Stress Cardiomyopathy

INTRODUCTION

Intra-aortic counterpulsation balloon pumps (IABPs) have been widely used to augment hemodynamics in critically ill patients with cardiogenic shock and have recently been proposed as a management strategy for subarachnoid hemorrhage (SAH) patients with neurogenic stress cardiomyopathy (NSC). Prior case series have described the use of IABP as a means to manage cardiogenic shock in this patient population; however, we sought to describe our experience with IABP as a means to wean vasopressor requirement while augmenting hemodynamics and maintaining pressures at goal.

METHODS

Five patients were identified from a single center, prospective, observational cohort study that received an IABP for the management of ischemia related to cerebral vasospasm in the setting of NSC. We evaluated all cases for efficacy of IABP in reducing vasopressor requirement, and complications.

RESULTS

Vasopressor requirements were reduced by a mean of 50% (range 25-65%) following IABPs placement within 24-48 h. There were no significant complications from IABPs. Out of the five patients, the outcome in three cases was favorable (mRS≤1). Two patients suffered delayed cerebral ischemia (DCI), one patient passed away due to severe sepsis, and one patient was left with severe disability. Only one patient required anticoagulation and that was for a preexisting deep venous thrombosis.

CONCLUSION

The use of IABPs may be beneficial as an adjunctive therapy in SAH patients with concomitant symptomatic vasospasm and NSC.

[Intratumoral heterogeneity in renal cell carcinoma. Molecular basis and translational implications]

Advanced clear cell renal cell carcinoma is characterized by extensive intratumoral genomic heterogeneity and branched as well as convergent evolutionary traits with genomically different subclones evolving in parallel in the same tumor. Distinct driver mutations can be found in spatially separated subclones, which may hinder the development of novel targeted therapies. However, truncal mutations of the VHL tumor suppressor gene and chromosome 3p loss were ubiquitously detected and will hence continue to be a focus of future drug development. Nevertheless, genomic instability, enhanced tumor genome plasticity and intratumoral heterogeneity are likely to represent major challenges towards biomarker development and personalized patient care.

The embryo-placental CD15-positive "vasculogenic zones" as a source of propranolol-sensitive pediatric vascular tumors

OBJECTIVE

Propranolol-induced involution is a unique biological feature of some pediatric vascular tumors, for instance infantile hemangioma (IH), cerebral cavernoma or chorioangioma. Currently, the cellular origin of these distinct tumors is unclear. In this study, we tested the hypothesis that propranolol-responsive vascular tumors are derived from common vessel-forming CD15 + progenitor cells which occur in early gestation. The aim of this study was to identify the tumor-relevant CD15 + progenitors at the early stages of embryo-placental development.

MATERIALS AND METHODS

Human embryo-placental units of 4-8 weeks gestation and pediatric vascular tumors were tested for expression of the tumor-relevant markers CD15, CD31 and CD34.

RESULTS

Placental vessel-forming progenitors were characterized by immunostaining for CD15, CD31, and CD34. In embryonic tissue, a discontinuous CD15+/CD31+/CD34 + progenitors was detected in immature vessels of the skin, neural tube, spinal and cerebral meninges. Similarly, vessels in IH and chorioangioma exhibited a co-expression of CD15, CD31, and CD34. In contrast, the majority of embryonic vessels presented a CD31+/CD34+, but CD15-negative immunophenotypic pattern.

DISCUSSION

Our results suggest the existence of a CD15+ "vasculogenic zones" in the embryo-placental unit as well as in IH and chorioangioma. A site-specific correlation between normal embryo-placental and tumoral vessel-forming CD15 + progenitors was demonstrated.

CONCLUSION

Hence, site- and stage-specific CD15 + progenitors of vascular wall could be considered as propronalol-sensitive targets and source of pre- and postnatal vascular tumors. We propose, that the CD15+ "vasculogenic zones" are a site-specific reserve of multi-lineage progenitors that could be recruited in pre- and postnatal emergency situations.

Isolation of Exosomes from the Plasma of HIV-1 Positive Individuals

Exosomes are small vesicles ranging in size from 30 nm to 100 nm that are released both constitutively and upon stimulation from a variety of cell types. They are found in a number of biological fluids and are known to carry a variety of proteins, lipids, and nucleic acid molecules. Originally thought to be little more than reservoirs for cellular debris, the roles of exosomes regulating biological processes and in diseases are increasingly appreciated. Several methods have been described for isolating exosomes from cellular culture media and biological fluids. Due to their small size and low density, differential ultracentrifugation and/or ultrafiltration are the most commonly used techniques for exosome isolation. However, plasma of HIV-1 infected individuals contains both exosomes and HIV viral particles, which are similar in size and density. Thus, efficient separation of exosomes from HIV viral particles in human plasma has been a challenge. To address this limitation, we developed a procedure modified from Cantin et. al., 2008 for purification of exosomes from HIV particles in human plasma. Iodixanol velocity gradients were used to separate exosomes from HIV-1 particles in the plasma of HIV-1 positive individuals. Virus particles were identified by p24 ELISA. Exosomes were identified on the basis of exosome markers acetylcholinesterase (AChE), and the CD9, CD63, and CD45 antigens. Our gradient procedure yielded exosome preparations free of virus particles. The efficient purification of exosomes from human plasma enabled us to examine the content of plasma-derived exosomes and to investigate their immune modulatory potential and other biological functions.

Cooperation of BRAF(F595L) and mutant HRAS in histiocytic sarcoma provides new insights into oncogenic BRAF signaling

Activating BRAF mutations, in particular V600E/K, drive many cancers and are considered mutually exclusive with mutant RAS, whereas inactivating BRAF mutations in the D(594)F(595)G(596) motif cooperate with RAS via paradoxical MEK/ERK activation. Due to the increasing use of comprehensive tumor genomic profiling, many non-V600 BRAF mutations are being detected whose functional consequences and therapeutic actionability are often unknown. We investigated an atypical BRAF mutation, F595L, which was identified along with mutant HRAS in histiocytic sarcoma and also occurs in epithelial cancers, melanoma and neuroblastoma, and determined its interaction with mutant RAS. Unlike other DFG motif mutants, BRAF(F595L) is a gain-of-function variant with intermediate activity that does not act paradoxically, but nevertheless cooperates with mutant RAS to promote oncogenic signaling, which is efficiently blocked by pan-RAF and MEK inhibitors. Mutation data from patients and cell lines show that BRAF(F595L), as well as other intermediate-activity BRAF mutations, frequently coincide with mutant RAS in various cancers. These data define a distinct class of activating BRAF mutations, extend the spectrum of patients with systemic histiocytoses and other malignancies who are candidates for therapeutic blockade of the RAF-MEK-ERK pathway and underscore the value of comprehensive genomic testing for uncovering the vulnerabilities of individual tumors.

Inhibition of Notch1 signaling overcomes resistance to the death ligand Trail by specificity protein 1-dependent upregulation of death receptor 5

The Notch1 signaling pathway contributes to tumorigenesis by influencing differentiation, proliferation and apoptosis. Here, we demonstrate that inhibition of the Notch1 signaling pathway sensitizes glioblastoma cell lines and glioblastoma initiating cells to apoptosis induced by the death ligand TRAIL. This sensitization occurs through transcriptional upregulation of the death receptor 5 (DR5, TRAIL-R2). The increase in DR5 expression is abrogated by concomitant repression of the transcription factor Sp1, which directly binds to the DR5 promoter in the absence of Notch1 as revealed by chromatin immunoprecipitation. Consistent with these findings, Notch1 inhibition resulted in increased DR5 promoter activity, which was impaired by mutation of one out of two Sp1-binding sites within the proximal DR5 promoter. Moreover, we demonstrate that JNK signaling contributes to the regulation of DR5 expression by Notch1. Taken together, our results identify Notch1 as key driver for TRAIL resistance and suggest Notch1 as a promising target for anti-glioblastoma therapy.

Chemie an starren Grenzflächen, 8. [1] Kinetik der Heterogenumsetzung kovalent über Spacer an Aerosil gebundener Aminogruppen (Aminoaerosil) mit homogen gelösten Isothiocyanaten / Chemistry on Rigid Interfaces, 8 . [1] Kinetics of Suspensions of Aminoaerosil (Aerosil Covalently Linked with 3-Aminopropylgroups) with Isothiocyanates in Homogeneous Solution

In aminoaerosil, the products of the reaction of γ-aminopropyltriethoxysilane with aerosil. an intraparticular interaction of the basic amino groups with the acidic silanol groups is observed. This behaviour was established a) by adsorption experiments using n-butylamine on aerosil. resp. aminoaerosil of different support density, and b) by microcalorimetric determination of the adsorption energy of acetonitrile using aerosil and aminoaerosils of different support density as substrates.

Aminoaerosils react with isothiocyanates according to (I) with formation of covalently linked thiourea groups. Fig. 3 and Fig. 5 (with trimethylamino) show the time-turnover curves of aminoaerosils of different support density with phenylisothiocyanate. The influence of the tem­perature on the thiourea formation is demonstrated in Table III. Depending on the polarity and the size of the ligands R. the isothiocyanates react with different reaction rates with aminoaerosil (Fig. 6). Aminoaerosils with different coverage density, but with an equal molarity of amino groups and varying specific surfaces, react non-uniformly with phenylisothiocyanate (Table IV).

The comparison of the reaction of phenylisothiocyanates a) with heterogeneously by suspended aminoaerosil and b) with n-butylamine in homogeneous solution, both with equal molar amounts of NH2, shows characteristic differences (Fig. 8).

The amount of the covalently linked NH2-groups in aminoaerosils can be determined using Sanger’s reagent.

Peptide-based identification of functional motifs and their binding partners

Specific short peptides derived from motifs found in full-length proteins, in our case HIV-1 Nef, not only retain their biological function, but can also competitively inhibit the function of the full-length protein. A set of 20 Nef scanning peptides, 20 amino acids in length with each overlapping 10 amino acids of its neighbor, were used to identify motifs in Nef responsible for its induction of apoptosis. Peptides containing these apoptotic motifs induced apoptosis at levels comparable to the full-length Nef protein. A second peptide, derived from the Secretion Modification Region (SMR) of Nef, retained the ability to interact with cellular proteins involved in Nef's secretion in exosomes (exNef). This SMRwt peptide was used as the "bait" protein in co-immunoprecipitation experiments to isolate cellular proteins that bind specifically to Nef's SMR motif. Protein transfection and antibody inhibition was used to physically disrupt the interaction between Nef and mortalin, one of the isolated SMR-binding proteins, and the effect was measured with a fluorescent-based exNef secretion assay. The SMRwt peptide's ability to outcompete full-length Nef for cellular proteins that bind the SMR motif, make it the first inhibitor of exNef secretion. Thus, by employing the techniques described here, which utilize the unique properties of specific short peptides derived from motifs found in full-length proteins, one may accelerate the identification of functional motifs in proteins and the development of peptide-based inhibitors of pathogenic functions.

Preoperative therapy of esophagogastric cancer: the problem of nonresponding patients

INTRODUCTION

Preoperative treatment is nowadays standard for locally advanced esophagogastric cancer in Europe. Surprisingly, little attention has been paid to nonresponders so far. The aim of our retrospective exploratory study was the comparison of responder, nonresponder, and primary resected patients in respect of outcome considering the tumor entity.

PATIENTS AND METHODS

From 2001-2011, 607 patients with locally advanced esophagogastric carcinoma (adenocarcinoma of the esophagogastric junction (AEG), n = 293; squamous cell cancer (SCC), n = 111; gastric cancer, n = 203) after preoperative treatment (n = 281) or primary resection (n = 326) were included. Histopathological response evaluation (Becker criteria) was available for 263.

RESULTS

A total of 76/263 (28.9 %) were responders (<10 % residual tumor). There was an association of response with increased R0 resections (p < 0.001) but also with a higher complication rate (p = 0.008) compared to nonresponse and primary surgery. Mortality was not influenced. Increased R0 resections after response were confirmed in every tumor entity (AEG, p = 0.010; SCC, p = 0.023; gastric cancer, p = 0.006). Median survival was best for responders with 43.5 months [95 % confidence interval (CI), 27.9-59.1], followed by nonresponders with 24.3 months (95 % CI, 21.6-27.0) and primary resected patients with 20.8 months (95 % CI, 17.7-23.9; p = 0.002). AEG (p = 0.012) and gastric cancer (p = 0.017) revealed identical results, but in the subgroup of SCC, the survival of nonresponders (median, 11.6 months; 95 % CI, 6.9-16.3) was even worse than for primary resected patients (median, 23.8 months; 95 % CI, 1.7-46.0; p = 0.012).

CONCLUSION

The histopathological response rate was low. Generally, nonresponding patients with AEG or gastric cancer seem not to have a disadvantage compared to primary resected patients, but nonresponders with SCC have a worse prognosis, which strengthens the demand for a critical patient selection in surgery for this tumor entity.

[Mechanisms of cell death. Novel insights and implications for tumor pathology]

During tumorigenesis cancer cells acquire certain features allowing for sustained growth and circumvention of programmed cell death. For decades cancer research has been focused on the molecular mechanisms of apoptosis and how to overcome apoptosis resistance in tumor cells. Meanwhile, novel types of programmed cell death have turned out to be important for both physiological and pathological processes. Recent findings imply that induction of alternative forms of programmed cell death, such as necroptosis, might be used as a therapeutic approach to overcome therapy resistance in cancer.

Verrucous carcinoma in epidermolysis bullosa simplex is possibly associated with a novel mutation in the keratin 5 gene

Epidermolysis bullosa simplex (EBS) is mainly caused by mutations in the KRT5 and KRT14 genes. Squamous cell carcinoma (SCC) represents the second most frequent skin neoplasia with complex aetiology. The molecular events disrupting the orchestrated interplay between the cytoskeleton, cell adhesion molecules and signalling proteins are ill understood in SCC. We describe the molecular background and the unusual course of the disease in a patient with EBS Dowling-Meara, severe keratoderma and a massive verrucous carcinoma. Skin and tumour samples from the patient were analysed using light microscopy, immunohistochemistry and immunofluorescence mapping. Mutation analysis of the KRT5 and KRT14 genes identified the novel KRT5 mutation p.E477D. Invasive tumour areas were characterized by downregulation of keratins 5 and 14, reduced and irregular desmocollin-2 expression and increased expression of keratins 6, 16 and 17. Levels of Ki-67 were increased and levels of E-cadherin strongly reduced in the tumour tissue. In this case a novel KRT5 mutation led to increased fragility of keratinocytes. Desmosome and adherens junctions were destabilized, which may trigger keratinocyte-mediated inflammation, possibly via p120-catenin-dependent signalling, suggesting a link between a keratin mutation and SCC, which adds weight to the hypothesis that disturbance of the cytoskeleton represents a major cause in the appearance of the malignant phenotype. Some individuals with EBS may be at risk of developing secondary SCC.