In vivo interaction screening reveals liver-derived constraints to metastasis.

It is estimated that only 0.02% of disseminated tumour cells are able to seed overt metastases1. While this suggests the presence of environmental constraints to metastatic seeding, the landscape of host factors controlling this process remains largely unclear. Here, combining transposon technology2 and fluorescence niche labelling3, we developed an in vivo CRISPR activation screen to systematically investigate the interactions between hepatocytes and metastatic cells. We identify plexin B2 as a critical host-derived regulator of liver colonization in colorectal and pancreatic cancer and melanoma syngeneic mouse models. We dissect a mechanism through which plexin B2 interacts with class IV semaphorins on tumour cells, leading to KLF4 upregulation and thereby promoting the acquisition of epithelial traits. Our results highlight the essential role of signals from the liver parenchyma for the seeding of disseminated tumour cells before the establishment of a growth-promoting niche. Our findings further suggest that epithelialization is required for the adaptation of CRC metastases to their new tissue environment. Blocking the plexin-B2-semaphorin axis abolishes metastatic colonization of the liver and therefore represents a therapeutic strategy for the prevention of hepatic metastases. Finally, our screening approach, which evaluates host-derived extrinsic signals rather than tumour-intrinsic factors for their ability to promote metastatic seeding, is broadly applicable and lays a framework for the screening of environmental constraints to metastasis in other organs and cancer types.

High throughput spatial immune mapping reveals an innate immune scar in post-COVID-19 brains.

The underlying pathogenesis of neurological sequelae in post-COVID-19 patients remains unclear. Here, we used multidimensional spatial immune phenotyping and machine learning methods on brains from initial COVID-19 survivors to identify the biological correlate associated with previous SARS-CoV-2 challenge. Compared to healthy controls, individuals with post-COVID-19 revealed a high percentage of TMEM119+P2RY12+CD68+Iba1+HLA-DR+CD11c+SCAMP2+ microglia assembled in prototypical cellular nodules. In contrast to acute SARS-CoV-2 cases, the frequency of CD8+ parenchymal T cells was reduced, suggesting an immune shift toward innate immune activation that may contribute to neurological alterations in post-COVID-19 patients.

Assessing bolus peak position in CT perfusion: High variance persisting despite age-dependency in a large cohort.

PURPOSE: CT perfusion (CTP) is a valuable tool in suspected acute ischemic stroke. A substantial variability of the delay between contrast injection and bolus arrival in the brain is conceivable. We investigated the distribution of the peak positions of the concentration time curves measured in an artery (arterial input function, AIF) and - in cases with ischemia - also measured in the penumbra. METHODS: We report on 2624 perfusion scans (52 % female, mean age 72.2 ± 14.4 years) with stroke present in 1636 cases. From the attenuation time curves of the AIF and the penumbra, we calculated the respective bolus peak positions and investigated the distribution of the peak positions. Further, we analyzed the bolus peak positions for associations with age. RESULTS: The bolus peaked significantly later in older patients, both in the AIF and in the penumbra (all p < 0.001). In the whole cohort, we found a significant association of age with the bolus peak position of the AIF (ρ = 0.334; p < 0.001). In patients with stroke, age was also associated to the peak position of the AIF (ρ = 0.305; p < 0.001), and the penumbra (ρ = 0.246, p < 0.001). However, a substantial range of peak positions of the AIF and penumbra was noted across all age ranges. CONCLUSIONS: This study revealed a strong age-dependency of the contrast bolus arrival in both healthy and ischemic tissue. This variability makes non-uniform sampling schemes, which have been suggested to reduce radiation dose, problematic, as they might not always optimally capture the bolus in all cases.

Impact of Mastectomy Flap Necrosis on Patient-Reported Quality-of-Life Measures After Nipple-Sparing Mastectomy: A Preliminary Analysis.

BACKGROUND: Mastectomy skin flap necrosis (SFN) is common following nipple-sparing mastectomy (NSM), but studies on its quality-of-life (QOL) impact are limited. We examined patient-reported QOL and satisfaction after NSM with/without SFN utilizing the BREAST-Q patient-reported outcome measure (PROM) survey. PATIENTS AND METHODS: Patients undergoing NSM between April 2018 and July 2021 at our institution were examined; the BREAST-Q PROM was administered preoperatively, and at 6 months and 1 year postoperatively. SFN extent/severity was documented at 2-3 weeks postoperatively; QOL and satisfaction domains were compared between patients with/without SFN. RESULTS: A total of 573 NSMs in 333 patients were included, and 135 breasts in 82 patients developed SFN (24% superficial, 56% partial thickness, 16% full thickness). Patients with SFN reported significantly lower scores in the satisfaction with breasts (p = 0.032) and psychosocial QOL domains (p = 0.009) at 6 months versus those without SFN, with scores returning to baseline at 1 year in both domains. In the "physical well-being-of-the-chest" domain, there was an overall decline in scores among all patients; however, there were no significant differences at any time point between patients with or without SFN. Sexual well-being scores declined for patients with SFN compared with those without at 6 months and also at 1 year, but this did not reach significance (p = 0.13, p = 0.2, respectively). CONCLUSIONS: Patients undergoing NSM who developed SFN reported significantly lower satisfaction and psychosocial well-being scores at 6 months, which returned to baseline by 1 year. Physical well-being of the chest significantly declines after NSM regardless of SFN. Future studies with larger sample sizes and longer follow-up are needed to determine SFN's impact on long-term QOL.

In vivo single-cell CRISPR uncovers distinct TNF programmes in tumour evolution.

The tumour evolution model posits that malignant transformation is preceded by randomly distributed driver mutations in cancer genes, which cause clonal expansions in phenotypically normal tissues. Although clonal expansions can remodel entire tissues1-3, the mechanisms that result in only a small number of clones transforming into malignant tumours remain unknown. Here we develop an in vivo single-cell CRISPR strategy to systematically investigate tissue-wide clonal dynamics of the 150 most frequently mutated squamous cell carcinoma genes. We couple ultrasound-guided in utero lentiviral microinjections, single-cell RNA sequencing and guide capture to longitudinally monitor clonal expansions and document their underlying gene programmes at single-cell transcriptomic resolution. We uncover a tumour necrosis factor (TNF) signalling module, which is dependent on TNF receptor 1 and involving macrophages, that acts as a generalizable driver of clonal expansions in epithelial tissues. Conversely, during tumorigenesis, the TNF signalling module is downregulated. Instead, we identify a subpopulation of invasive cancer cells that switch to an autocrine TNF gene programme associated with epithelial-mesenchymal transition. Finally, we provide in vivo evidence that the autocrine TNF gene programme is sufficient to mediate invasive properties and show that the TNF signature correlates with shorter overall survival of patients with squamous cell carcinoma. Collectively, our study demonstrates the power of applying in vivo single-cell CRISPR screening to mammalian tissues, unveils distinct TNF programmes in tumour evolution and highlights the importance of understanding the relationship between clonal expansions in epithelia and tumorigenesis.

Real-world effectiveness of first-line azacitidine or decitabine with or without venetoclax in acute myeloid leukemia patients unfit for intensive therapy.

BACKGROUND: First-line treatment in patients with acute myeloid leukemia (AML) unfit for intensive therapy is the combination of a hypomethylating agent (HMA) with venetoclax (VEN). However, retrospective data confirming the benefits of this regimen outside of clinical trials have shown conflicting results. METHODS: We performed a multicenter retrospective analysis of outcomes with first-line HMA-VEN versus HMA in AML patients unfit for intensive chemotherapy. RESULTS: A total of 213 patients were included from three German hospitals (125 HMA-VEN, 88 HMA). Median overall survival in the HMA-VEN cohort was 7.9 months (95% confidence interval [CI], 5.1-14.7) versus 4.9 months (3.1-7.1) with HMA. After 1 year, 42% (95% CI, 33-54) and 19% (12-30) of patients were alive, respectively (hazard ratio [HR] for death, 0.64; 95% CI, 0.46-0.88). After adjusting for clinical and molecular baseline characteristics, treatment with HMA-VEN remained significantly associated with both prolonged survival (HR, 0.48; 95% CI, 0.29-0.77) and time to next treatment (HR, 0.63; 95% CI, 0.47-0.85). Patients who achieved recovery of peripheral blood counts had a favorable prognosis (HR for death, 0.52; 95% CI, 0.33-0.84). DISCUSSION: These data align with findings from the pivotal VIALE-A trial and support the use of HMA-VEN in patients unfit for intensive therapy.

Osseous Maxillary Reconstruction with Immediate Dental Implant Placement: An Optimized Workflow for the Oncologic Patient.

INTRODUCTION: Maxillary reconstruction is a complex undertaking characterized by a 3-dimensional surgical site with deficiencies in multiple tissue types. Prior to virtual surgical planning(VSP), bony reconstruction was inaccurate and inefficient, thus reconstructions defaulted to soft tissue flaps or obturators. The current study describes an efficient and accurate approach to bony maxillary reconstruction with immediate dental implant placement(IDIP). METHODS: A reconstructive workflow was developed for osseous reconstruction to improve functional and aesthetic outcomes. Critical aspects include VSP, 3-D printed plates and IDIP. Review of a prospectively maintained database identified patients who underwent osseous maxillary reconstruction with a fibula flap and immediate dental implants from 2017-2022, with a focus on oncologic characteristics and reconstructive outcomes. RESULTS: During the study, 20 patients underwent maxillary reconstruction with VSP and IDIP. One dental implant out of 55 failed to osseointegrate and no flaps were lost. Three patients suffered partial loss of the fibula skin island; one required palatal closure with a radial forearm flap, and two were managed with outpatient debridement. Fifteen patients achieved either an interim or final retained dental prosthesis. All prostheses achieved acceptable aesthetic results without the instability associated with non-bone borne devices(e.g.dentures/obturators). No patients experienced delays in oncologic treatment. CONCLUSIONS: VSP technology has enabled surgeons to replace like with like to achieve better outcomes with acceptable morbidity for maxillary defects. IDIP provides all patients an opportunity for a fixed prosthesis even though not all complete the process. This maxillary reconstruction workflow can be safely accomplished in oncologic patients with promising and effective early results.

Optimizing accrual to a large-scale, clinically integrated randomized trial in anesthesiology: A 2-year analysis of recruitment.

BACKGROUND: Performing large randomized trials in anesthesiology is often challenging and costly. The clinically integrated randomized trial is characterized by simplified logistics embedded into routine clinical practice, enabling ease and efficiency of recruitment, offering an opportunity for clinicians to conduct large, high-quality randomized trials under low cost. Our aims were to (1) demonstrate the feasibility of the clinically integrated trial design in a high-volume anesthesiology practice and (2) assess whether trial quality improvement interventions led to more balanced accrual among study arms and improved trial compliance over time. METHODS: This is an interim analysis of recruitment to a cluster-randomized trial investigating three nerve block approaches for mastectomy with immediate implant-based reconstruction: paravertebral block (arm 1), paravertebral plus interpectoral plane blocks (arm 2), and serratus anterior plane plus interpectoral plane blocks (arm 3). We monitored accrual and consent rates, clinician compliance with the randomized treatment, and availability of outcome data. Assessment after the initial year of implementation showed a slight imbalance in study arms suggesting areas for improvement in trial compliance. Specific improvement interventions included increasing the frequency of communication with the consenting staff and providing direct feedback to clinician investigators about their individual recruitment patterns. We assessed overall accrual rates and tested for differences in accrual, consent, and compliance rates pre- and post-improvement interventions. RESULTS: Overall recruitment was extremely high, accruing close to 90% of the eligible population. In the pre-intervention period, there was evidence of bias in the proportion of patients being accrued and receiving the monthly block, with higher rates in arm 3 (90%) compared to arms 1 (81%) and 2 (79%, p = 0.021). In contrast, in the post-intervention period, there was no statistically significant difference between groups (p = 0.8). Eligible for randomization rate increased from 89% in the pre-intervention period to 95% in the post-intervention period (difference 5.7%; 95% confidence interval = 2.2%-9.4%, p = 0.002). Consent rate increased from 95% to 98% (difference of 3.7%; 95% confidence interval = 1.1%-6.3%; p = 0.004). Compliance with the randomized nerve block approach was maintained at close to 100% and availability of primary outcome data was 100%. CONCLUSION: The clinically integrated randomized trial design enables rapid trial accrual with a high participant compliance rate in a high-volume anesthesiology practice. Continuous monitoring of accrual, consent, and compliance rates is necessary to maintain and improve trial conduct and reduce potential biases. This trial methodology serves as a template for the implementation of other large, low-cost randomized trials in anesthesiology.

Satisfaction with Breasts Following Autologous Reconstruction: Assessing Associated Factors and the Impact of Revisions.

BACKGROUND: Autologous breast reconstruction (ABR) may confer higher patient reported outcomes than implant breast reconstruction, but an in-depth examination of factors associated with satisfaction after ABR is lacking. We aimed to determine independent predictors of 1-year Satisfaction with Breasts after ABR and assess the importance of elective procedures on satisfaction. METHODS: A retrospective analysis of patients who underwent abdominal-based ABR between 2010 and 2021 and completed the BREAST-Q Satisfaction with Breasts module at 1-year was performed. Elective procedures comprised of breast revision and nipple areolar complex (NAC) reconstruction. RESULTS: 959 patients were included. Satisfaction with Breasts score improved from 53 (IQR: 44 to 64) preoperatively to 64 (53 to 78) at 1-year postoperatively (p<0.001). Factors significantly associated with decreased postoperative score included lower preoperative scores (ß=0.19 [95% CI: 0.08, 0.31], p=0.001), older age (ß=-0.17 [-0.34, -0.01], p=0.042), Asian race (versus White, ß=-6.7 [-12, -1.7], p=0.008), and a history of psychiatric diagnoses (ß=-3.4 [-6.2, -0.66], p=0.015). Patients who received radiation (ß=-5.6 [-9.0, -2.3], p=0.001) or had mastectomy skin flap/nipple necrosis (ß=-3.8 [-7.6, -0.06], p=0.046) also had significantly decreased scores. Satisfaction with Breasts significantly improved after breast revision procedures (54 [42 to 65] to 65 [54 to 78], p<0.001) and NAC reconstruction (58 [47 to 71] to 67 [57 to 82], p<0.001). CONCLUSION: Multiple independent patient and treatment level factors are associated with lower 1-year Satisfaction with Breasts following ABR. Elective procedures have the potential to improve satisfaction. Understanding these findings is imperative for optimizing clinical decision making and managing expectations.

A Multi-institutional Analysis of a Textbook Outcome Among Patients Undergoing Microvascular Breast Reconstruction.

BACKGROUND: Individual outcomes may not accurately reflect the quality of perioperative care. Textbook outcomes (TOs) are composite metrics that provide a comprehensive evaluation of hospital performance and surgical quality. This study aimed to investigate the prevalence and predictors of TOs in a multi-institutional cohort of patients who underwent breast reconstruction with deep inferior epigastric artery perforator flaps. METHODS: For autologous reconstruction, a TO was previously defined as a procedure without intraoperative complications, reoperation, infection requiring intravenous antibiotics, readmission, mortality, systemic complications, operative duration ≤12 hours for bilateral and ≤10 hours for unilateral/stacked reconstruction, and length of stay (LOS) ≤5 days. We investigated associations between patient-level factors and achieving a TO using multivariable regression analysis. RESULTS: Of 1000 patients, most (73.2%) met a TO. The most common reasons for deviation from a TO were reoperation (9.6%), prolonged operative time (9.5%), and prolonged LOS (9.2%). On univariate analysis, tobacco use, obesity, widowed/divorced marital status, and contralateral prophylactic mastectomy or bilateral reconstruction were associated with a lower likelihood of TOs (P < 0.05). After adjustment, bilateral prophylactic mastectomy (odds ratio [OR], 5.71; P = 0.029) and hormonal therapy (OR, 1.53; P = 0.050) were associated with a higher likelihood of TOs; higher body mass index (OR, 0.91; P = <0.001) was associated with a lower likelihood. CONCLUSION: Approximately 30% of patients did not achieve a TO, and the likelihood of achieving a TO was influenced by patient and procedural factors. Future studies should investigate how this metric may be used to evaluate patient and hospital-level performance to improve the quality of care in reconstructive surgery.

Inflammation-Triggered Enlargement of Choroid Plexus in Subacute COVID-19 Patients with Neurological Symptoms.

OBJECTIVE: To investigate whether choroid plexus volumes in subacute coronavirus disease 2019 (COVID-19) patients with neurological symptoms could indicate inflammatory activation or barrier dysfunction and assess their association with clinical data. METHODS: Choroid plexus volumes were measured in 28 subacute COVID-19 patients via cerebral magnetic resonance imaging (MRI), compared with those in infection-triggered non-COVID-19 encephalopathy patients (n = 25), asymptomatic individuals after COVID-19 (n = 21), and healthy controls (n = 21). Associations with inflammatory serum markers (peak counts of leukocytes, C-reactive protein [CRP], interleukin 6), an MRI-based marker of barrier dysfunction (CSF volume fraction [V-CSF]), and clinical parameters like olfactory performance and cognitive scores (Montreal Cognitive Assessment) were investigated. RESULTS: COVID-19 patients showed significantly larger choroid plexus volumes than control groups (p < 0.001, η2 = 0.172). These volumes correlated significantly with peak leukocyte levels (p = 0.001, Pearson's r = 0.621) and V-CSF (p = 0.009, Spearman's rho = 0.534), but neither with CRP nor interleukin 6. No significant correlations were found with clinical parameters. INTERPRETATION: In patients with subacute COVID-19, choroid plexus volume is a marker of central nervous system inflammation and barrier dysfunction in the presence of neurologic symptoms. The absence of plexus enlargement in infection-triggered non-COVID-19 encephalopathy suggests a specific severe acute respiratory syndrome coronavirus 2 effect. This study also documents an increase in choroid plexus volume for the first time as a parainfectious event. ANN NEUROL 2024.

AXIN1 mutations in nonsyndromic craniosynostosis.

OBJECTIVE: Occurring once in every 2000 live births, craniosynostosis (CS) is the most frequent cranial birth defect. Although the genetic etiologies of syndromic CS cases are well defined, the genetic cause of most nonsyndromic cases remains unknown. METHODS: The authors analyzed exome or RNA sequencing data from 876 children with nonsyndromic CS, including 291 case-parent trios and 585 additional probands. The authors also utilized the GeneMatcher platform and the Gabriella Miller Kids First genome sequencing project to identify additional CS patients with AXIN1 mutations. RESULTS: The authors describe 11 patients with nonsyndromic CS harboring rare, damaging mutations in AXIN1, an inhibitor of Wnt signaling. AXIN1 regulates signaling upstream of key mediators of osteoblast differentiation. Three of the 6 mutations identified in trios occurred de novo in the proband, while 3 were transmitted from unaffected parents. Patients with nonsyndromic CS were highly enriched for mutations in AXIN1 compared to both expectation (p = 0.0008) and exome sequencing data from > 76,000 healthy controls (p = 2.3 × 10-6), surpassing the thresholds for genome-wide significance. CONCLUSIONS: These findings describe the first phenotype associated with mutations in AXIN1, with mutations identified in approximately 1% of nonsyndromic CS cases. The results strengthen the existing link between Wnt signaling and maintenance of cranial suture patency and have implications for genetic testing in families with CS.

Catabolism and interactions of syntrophic propionate- and acetate oxidizing microorganisms under mesophilic, high-ammonia conditions.

Microbial inhibition by high ammonia concentrations is a recurring problem that significantly restricts methane formation from intermediate acids, i.e., propionate and acetate, during anaerobic digestion of protein-rich waste material. Studying the syntrophic communities that perform acid conversion is challenging, due to their relatively low abundance within the microbial communities typically found in biogas processes and disruption of their cooperative behavior in pure cultures. To overcome these limitations, this study examined growth parameters and microbial community dynamics of highly enriched mesophilic and ammonia-tolerant syntrophic propionate and acetate-oxidizing communities and analyzed their metabolic activity and cooperative behavior using metagenomic and metatranscriptomic approaches. Cultivation in batch set-up demonstrated biphasic utilization of propionate, wherein acetate accumulated and underwent oxidation before complete degradation of propionate. Three key species for syntrophic acid degradation were inferred from genomic sequence information and gene expression: a syntrophic propionate-oxidizing bacterium (SPOB) "Candidatus Syntrophopropionicum ammoniitolerans", a syntrophic acetate-oxidizing bacterium (SAOB) Syntrophaceticus schinkii and a novel hydrogenotrophic methanogen, for which we propose the provisional name "Candidatus Methanoculleus ammoniitolerans". The results revealed consistent transcriptional profiles of the SAOB and the methanogen both during propionate and acetate oxidation, regardless of the presence of an active propionate oxidizer. Gene expression indicated versatile capabilities of the two syntrophic bacteria, utilizing both molecular hydrogen and formate as an outlet for reducing equivalents formed during acid oxidation, while conserving energy through build-up of sodium/proton motive force. The methanogen used hydrogen and formate as electron sources. Furthermore, results of the present study provided a framework for future research into ammonia tolerance, mobility, aggregate formation and interspecies cooperation.

Association Between Vegetation Size and Outcome in the Partial Oral Antibiotic Endocarditis Treatment Trial.

Step-down oral antibiotic therapy is associated with a non-inferior long-term outcome compared with continued intravenous antibiotic therapy in the treatment of left-sided infective endocarditis. We aimed to analyze whether step-down oral therapy compared with continued intravenous antibiotic therapy is also associated with a non-inferior outcome in patients with large vegetations (vegetation length ≥ 10 mm) or among patients who underwent surgery before step-down oral therapy. We included patients without presence of aortic root abscess at diagnosis from the POET (Partial Oral Antibiotic Endocarditis Treatment) study. Multivariable Cox regression analyses were used to find associations between large vegetation, cardiac surgery, step-down oral therapy, and the primary end point (composite of all-cause mortality, unplanned cardiac surgery, embolic event, or relapse of positive blood cultures during follow-up). A total of 368 patients (age 68 ± 12, 77% men) were included. Patients with large vegetations (n = 124) were more likely to undergo surgery compared with patients with small vegetations (n = 244) (65% vs 20%, p <0.001). During a median 1,406 days of follow-up, 146 patients reached the primary end point. Large vegetations were not associated with the primary end point (hazard ratio 0.74, 95% confidence interval 0.47 to 1.18, p = 0.21). Step-down oral therapy was non-inferior to continued intravenous antibiotic in all subgroups when stratified by the presence of a large vegetation at baseline and early cardiac surgery. Step-down oral therapy is safe in the presence of a large vegetation at diagnosis and among patients who underwent early cardiac surgery.