Surveillance for Pancreatic Cancer in High-Risk Individuals Leads to Improved Outcomes: A Propensity Score-Matched Analysis.

BACKGROUND & AIMS: Recent pancreatic cancer surveillance programs of high-risk individuals have reported improved outcomes. This study assessed to what extent outcomes of pancreatic ductal adenocarcinoma (PDAC) in patients with a CDKN2A/p16 pathogenic variant diagnosed under surveillance are better as compared with patients with PDAC diagnosed outside surveillance. METHODS: In a propensity score matched cohort using data from the Netherlands Cancer Registry, we compared resectability, stage, and survival between patients diagnosed under surveillance with non-surveillance patients with PDAC. Survival analyses were adjusted for potential effects of lead time. RESULTS: Between January 2000 and December 2020, 43,762 patients with PDAC were identified from the Netherlands Cancer Registry. Thirty-one patients with PDAC under surveillance were matched in a 1:5 ratio with 155 non-surveillance patients based on age at diagnosis, sex, year of diagnosis, and tumor location. Outside surveillance, 5.8% of the patients had stage I cancer, as compared with 38.7% of surveillance patients with PDAC (odds ratio [OR], 0.09; 95% confidence interval [CI], 0.04-0.19). In total, 18.7% of non-surveillance patients vs 71.0% of surveillance patients underwent a surgical resection (OR, 10.62; 95% CI, 4.56-26.63). Patients in surveillance had a better prognosis, reflected by a 5-year survival of 32.4% and a median overall survival of 26.8 months vs 4.3% 5-year survival and 5.2 months median overall survival in non-surveillance patients (hazard ratio, 0.31; 95% CI 0.19-0.50). For all adjusted lead times, survival remained significantly longer in surveillance patients than in non-surveillance patients. CONCLUSION: Surveillance for PDAC in carriers of a CDKN2A/p16 pathogenic variant results in earlier detection, increased resectability, and improved survival as compared with non-surveillance patients with PDAC.

Hypoxia-driven immunosuppression by Treg and type-2 conventional dendritic cells in HCC.

BACKGROUND AND AIMS: Hypoxia is one of the central players in shaping the immune context of the tumor microenvironment (TME). However, the complex interplay between immune cell infiltrates within the hypoxic TME of HCC remains to be elucidated. APPROACH AND RESULTS: We analyzed the immune landscapes of hypoxia-low and hypoxia-high tumor regions using cytometry by time of light, immunohistochemistry, and transcriptomic analyses. The mechanisms of immunosuppression in immune subsets of interest were further explored using in vitro hypoxia assays. Regulatory T cells (Tregs) and a number of immunosuppressive myeloid subsets, including M2 macrophages and human leukocyte antigen-DR isotype (HLA-DRlo ) type 2 conventional dendritic cell (cDC2), were found to be significantly enriched in hypoxia-high tumor regions. On the other hand, the abundance of active granzyme Bhi PD-1lo CD8+ T cells in hypoxia-low tumor regions implied a relatively active immune landscape compared with hypoxia-high regions. The up-regulation of cancer-associated genes in the tumor tissues and immunosuppressive genes in the tumor-infiltrating leukocytes supported a highly pro-tumorigenic network in hypoxic HCC. Chemokine genes such as CCL20 (C-C motif chemokine ligand 20) and CXCL5 (C-X-C motif chemokine ligand 5) were associated with recruitment of both Tregs and HLA-DRlo cDC2 to hypoxia-high microenvironments. The interaction between Tregs and cDC2 under a hypoxic TME resulted in a loss of antigen-presenting HLA-DR on cDC2. CONCLUSIONS: We uncovered the unique immunosuppressive landscapes and identified key immune subsets enriched in hypoxic HCC. In particular, we identified a potential Treg-mediated immunosuppression through interaction with a cDC2 subset in HCC that could be exploited for immunotherapies.

Intraoperative Ultrasound During Surgical Exploration in Patients with Pancreatic Cancer and Vascular Involvement (ULTRAPANC): A Prospective Multicenter Study.

BACKGROUND: Determining the resectability of pancreatic cancer with vascular involvement on preoperative computed tomography imaging remains challenging, especially following preoperative chemotherapy and chemoradiotherapy. Intraoperative ultrasound (IOUS) may provide real-time additional information, but prospective multicenter series confirming its value are lacking. PATIENTS AND METHODS: This prospective multicenter study included patients undergoing surgical exploration for pancreatic cancer with vascular involvement. All patients underwent IOUS at the start of explorative laparotomy. Primary outcomes were resectability status as defined by the National Comprehensive Cancer Network and the extent of vascular involvement. RESULTS: Overall, 85 patients were included, of whom 74 (87%) were post preoperative chemotherapy, and mostly following FOLFIRINOX regimen (n = 57; 76%). On the basis of preoperative imaging, 34 (40%) patients were staged as resectable (RPC), 32 (38%) borderline resectable (BRPC), and 19 (22%) locally advanced pancreatic cancer (LAPC). IOUS changed the resectability status in 32/85 (38%) patients (p < 0.001), including 8/19 (42%) patients with LAPC who were downstaged (4 to BRPC, 4 to RPC), and 22/32 (69%) patients with BRPC who were downstaged to RPC. Among patients with presumed superior mesenteric artery (SMA) involvement, 20/28 (71%) had no SMA involvement on IOUS. In 15 of these 20 patients a pancreatic resection was performed, all with R0 SMA margin. CONCLUSION: IOUS during surgical exploration for pancreatic cancer and vascular involvement downstaged the resectability status in over one-third of patients, which could facilitate progress during surgical exploration. This finding should be confirmed by larger studies, including detailed pathology assessment. Trial Registration www.trialregister.nl (NL7621).

Uncoupling immune trajectories of response and adverse events from anti-PD-1 immunotherapy in hepatocellular carcinoma.

BACKGROUND & AIMS: While immune checkpoint blockade (ICB) has shown promise in patients with hepatocellular carcinoma (HCC), it is associated with modest response rates and immune-related adverse events (irAEs) are common. In this study, we aimed to decipher immune trajectories and mechanisms of response and/or irAEs in patients with HCC receiving anti-programmed cell death 1 (anti-PD-1) therapy. METHODS: Pre- and on-treatment peripheral blood samples (n = 60) obtained from 32 patients with HCC (Singapore cohort) were analysed by cytometry by time-of-flight and single-cell RNA sequencing, with flow cytometric validation in an independent Korean cohort (n = 29). Mechanistic validation was conducted by bulk RNA sequencing of 20 pre- and on-treatment tumour biopsies and using a murine HCC model treated with different immunotherapeutic combinations. RESULTS: Single-cell analyses identified CXCR3+CD8+ effector memory T (TEM) cells and CD11c+ antigen-presenting cells (APC) as associated with response (p = 0.0004 and 0.0255, respectively), progression-free survival (p = 0.00079 and 0.0015, respectively), and irAEs (p = 0.0034 and 0.0125, respectively) in anti-PD-1-treated patients with HCC. Type-1 conventional dendritic cells were identified as the specific APC associated with response, while 2 immunosuppressive CD14+ myeloid clusters were linked to reduced irAEs. Further analyses of CXCR3+CD8+ TEM cells showed cell-cell interactions specific to response vs. irAEs, from which the anti-PD-1 and anti-TNFR2 combination was harnessed to uncouple these effects, resulting in enhanced response without increased irAEs in a murine HCC model. CONCLUSIONS: This study identifies early predictors of clinical response to anti-PD-1 ICB in patients with HCC and offers mechanistic insights into the immune trajectories of these immune subsets at the interface between response and toxicity. We also propose a new combination immunotherapy for HCC to enhance response without exacerbating irAEs. CLINICAL TRIAL NUMBER: NCT03695952. LAY SUMMARY: Response rates to immune checkpoint blockade (ICB) treatment in hepatocellular carcinoma (HCC) remain modest and adverse events are common. Herein, we identified early predictors of response and gained an in-depth understanding of the immunological mechanisms behind response and adverse events in patients with HCC treated with ICB. We also proposed a new combination immunotherapy for HCC that enhances response without exacerbating adverse events.

Neoadjuvant Treatment with Angiogenesis-Inhibitor Dovitinib Prior to Local Therapy in Hepatocellular Carcinoma: A Phase II Study.

BACKGROUND: Hepatocellular carcinoma (HCC) recurrence rates following locoregional treatment are high. As multireceptor tyrosine kinase inhibitors targeting vascular endothelial growth factor receptors (VEGFRs) are effective in advanced HCC, we assessed the efficacy and safety of neoadjuvant systemic treatment with dovitinib in early- and intermediate-stage HCC. MATERIALS AND METHODS: Twenty-four patients with modified Child-Pugh class A early- and intermediate-stage HCC received neoadjuvant oral dovitinib 500 mg daily (5 days on/2 days off) for 4 weeks, followed by locoregional therapy. Primary endpoints were objective response rates and intratumoral blood flow changes. Secondary endpoints were safety, pharmacodynamical plasma markers of VEGFR-blockade, time to progression (TTP), and overall survival (OS). RESULTS: Modified RECIST overall response rate was 48%, including 13% complete remission, and despite dose reduction/interruption in 83% of patients, intratumoral perfusion index decreased significantly. Grade 3-4 adverse events, most frequently (on-target) hypertension (54%), fatigue (25%), and thrombocytopenia (21%), occurred in 88% of patients. Plasma VEGF-A, VEGF-D, and placental growth factor increased significantly, whereas sTie-2 decreased, consistent with VEGFR-blockade. Following neoadjuvant dovitinib, all patients could proceed to their original planned locoregional treatment. No delayed toxicity occurred. Seven patients (three early, four intermediate stage) underwent orthotopic liver transplant after median 11.4 months. Censoring at transplantation, median TTP and OS were 16.8 and 34.8 months respectively; median cancer-specific survival was not reached. CONCLUSION: Already after a short 4-week dovitinib treatment period, intratumoral blood flow reduction and modest antitumor responses were observed. Although these results support use of systemic neoadjuvant strategies, the poor tolerability indicates that dovitinib dose adaptations are required in HCC. IMPLICATIONS FOR PRACTICE: Orthotopic liver transplantation may cure early and intermediate-stage hepatocellular carcinoma. Considering the expected waiting time >6 months because of donor liver scarcity, there is an unmet need for effective neoadjuvant downsizing strategies. Angiogenesis inhibition by dovitinib does not negatively affect subsequent invasive procedures, is safe to administer immediately before locoregional therapy, and may provide a novel treatment approach to improve patient outcomes if tolerability in patients with hepatocellular carcinoma can be improved by therapeutic drug monitoring and personalized dosing.

Venous wedge and segment resection during pancreatoduodenectomy for pancreatic cancer: impact on short- and long-term outcomes in a nationwide cohort analysis.

BACKGROUND: Venous resection of the superior mesenteric or portal vein is increasingly performed in pancreatic cancer surgery, whereas results of studies on short- and long-term outcomes are contradictory. The aim of this study was to evaluate the impact of the type of venous resection in pancreatoduodenectomy for pancreatic cancer on postoperative morbidity and overall survival. METHODS: This nationwide retrospective cohort study included all patients who underwent pancreatoduodenectomy for pancreatic cancer in 18 centres (2013-2017). RESULTS: A total of 1311 patients were included, of whom 17 per cent underwent wedge resection and 10 per cent segmental resection. Patients with segmental resection had higher rates of major morbidity (39 versus 20 versus 23 per cent, respectively; P < 0.001) and portal or superior mesenteric vein thrombosis (18 versus 5 versus 1 per cent, respectively; P < 0.001) and worse overall survival (median 12 versus 16 versus 20 months, respectively; P < 0.001), compared to patients with wedge resection and those without venous resection. Multivariable analysis showed patients with segmental resection, but not those who had wedge resection, had higher rates of major morbidity (odds ratio = 1.93, 95 per cent c.i. 1.20 to 3.11) and worse overall survival (hazard ratio = 1.40, 95 per cent c.i. 1.10 to 1.78), compared to patients without venous resection. Among patients who received neoadjuvant therapy, there was no difference in overall survival among patients with segmental and wedge resection and those without venous resection (median 32 versus 25 versus 33 months, respectively; P = 0.470), although there was a difference in major morbidity rates (52 versus 19 versus 21 per cent, respectively; P = 0.012). CONCLUSION: In pancreatic surgery, the short- and long-term outcomes are worse in patients with venous segmental resection, compared to patients with wedge resection and those without venous resection.

Feasibility of Velocity-Selective Arterial Spin Labeling in Breast Cancer Patients for Noncontrast-Enhanced Perfusion Imaging.

BACKGROUND: Dynamic contrast-enhanced (DCE) MRI is the most sensitive method for detection of breast cancer. However, due to high costs and retention of intravenously injected gadolinium-based contrast agent, screening with DCE-MRI is only recommended for patients who are at high risk for developing breast cancer. Thus, a noncontrast-enhanced alternative to DCE is desirable. PURPOSE: To investigate whether velocity selective arterial spin labeling (VS-ASL) can be used to identify increased perfusion and vascularity within breast lesions compared to surrounding tissue. STUDY TYPE: Prospective. POPULATION: Eight breast cancer patients. FIELD STRENGTH/SEQUENCE: A 3 T; VS-ASL with multislice single-shot gradient-echo echo-planar-imaging readout. ASSESSMENT: VS-ASL scans were independently assessed by three radiologists, with 3-25 years of experience in breast radiology. Scans were scored on lesion visibility and artifacts, based on a 3-point Likert scale. A score of 1 corresponded to "lesions being distinguishable from background" (lesion visibility), and "no or few artifacts visible, artifacts can be distinguished from blood signal" (artifact score). A distinction was made between mass and nonmass lesions (based on BI-RADS lexicon), as assessed in the standard clinical exam. STATISTICAL TESTS: Intra-class correlation coefficient (ICC) for interobserver agreement. RESULTS: The ICC was 0.77 for lesion visibility and 0.84 for the artifact score. Overall, mass lesions had a mean score of 1.27 on lesion visibility and 1.53 on the artifact score. Nonmass lesions had a mean score of 2.11 on lesion visibility and 2.11 on the artifact score. DATA CONCLUSION: We have demonstrated the technical feasibility of bilateral whole-breast perfusion imaging using VS-ASL in breast cancer patients. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 1.

Surgical management and pathological assessment of pancreatoduodenectomy with venous resection: an international survey among surgeons and pathologists.

BACKGROUND: The aim of this survey was to gain insights in the current surgical management and pathological assessment of pancreatoduodenectomy with portal-superior mesenteric vein resection (VR). METHODS: A systematic literature search was performed to identify international expert surgeons (N = 150) and pathologists (N = 40) who published relevant studies between 2009 and 2019. These experts and Dutch surgeons (N = 17) and pathologists (N = 20) were approached to complete an online survey. RESULTS: Overall, 76 (46%) surgeons and 37 (62%) pathologists completed the survey. Most surgeons (71%) estimated that preoperative imaging corresponded correctly with intraoperative findings of venous involvement in 50-75% of patients. An increased complication risk following VR was expected by 55% of surgeons, mainly after Type 4 (segmental resection-venous conduit anastomosis). Most surgeons (61%) preferred Type 3 (segmental resection-primary anastomosis). Most surgeons (75%) always perform the VR themselves. Standard postoperative imaging for patency control was performed by 54% of surgeons and 39% adjusted thromboprophylaxis following VR. Most pathologists (76%) always assessed tumor infiltration in the resected vein and only 54% of pathologists always assess the resection margins of the vein itself. Variation in assessment of tumor infiltration depth was observed. CONCLUSION: This international survey showed variation in the surgical management and pathological assessment of pancreatoduodenectomy with venous involvement. This highlights the lack of evidence and emphasizes the need for research on imaging modalities to improve patient selection for VR, surgical techniques, postoperative management and standardization of the pathological assessment.

Multidimensional analyses reveal distinct immune microenvironment in hepatitis B virus-related hepatocellular carcinoma.

BACKGROUND AND AIMS: Chronic inflammation induced by chronic hepatitis B virus (HBV) infection increases the risk of hepatocellular carcinoma (HCC). However, little is known about the immune landscape of HBV-related HCC and its influence on the design of effective cancer immunotherapeutics. METHODS: We interrogated the immune microenvironments of HBV-related HCC and non-viral-related HCC using immunohistochemistry and cytometry by time-of-flight (CyTOF). On identifying unique immune subsets enriched in HBV-related HCC, we further interrogated their phenotypes and functions using next-generation sequencing (NGS) and in vitro T-cell proliferation assays. RESULTS: In-depth interrogation of the immune landscapes showed that regulatory T cells (TREG) and CD8+ resident memory T cells (TRM) were enriched in HBV-related HCC, whereas Tim-3+CD8+ T cells and CD244+ natural killer cells were enriched in non-viral-related HCC. NGS of isolated TREG and TRM from HBV-related HCC and non-viral-related HCC identified distinct functional signatures associated with T-cell receptor signalling, T-cell costimulation, antigen presentation and programmed cell death protein 1 (PD-1) signalling. TREG and TRM from HBV-related HCC expressed more PD-1 and were functionally more suppressive and exhausted than those from non-virus-related HCC. Furthermore, immunosuppression by PD-1+ TREG could be reversed with anti-PD-1 blockade. Using multiplexed tissue immunofluorescence, we further demonstrated that TREG and TRM contributed to overall patient survival: TREG were associated with a poor prognosis and TRM were associated with a good prognosis in HCC. CONCLUSION: We have shown that the HBV-related HCC microenvironment is more immunosuppressive and exhausted than the non-viral-related HCC microenvironment. Such in-depth understanding has important implications in disease management and appropriate application of immunotherapeutics.

Dilatation of the main pancreatic duct as first manifestation of small pancreatic ductal adenocarcinomas detected in a hereditary pancreatic cancer surveillance program.

BACKGROUND: MRI surveillance in a cohort of CDKN2A-p16-Leiden mutation carriers with a 20% lifetime risk of PDAC led to increased resection rates and improved survival. Patients with screen-detected PDAC were evaluated for main pancreatic duct (MPD) abnormalities in this retrospective review. METHODS: Since 2000 annual MRI and optional EUS was performed in mutation carriers. Data of patients with screen-detected PDAC was collected on gender, age at diagnosis, site of tumor, size, outcome of surgery, pathology findings and survival. All MRIs were re-evaluated for MPD abnormalities. RESULTS: 23 PDAC were detected in 22 (10%) of 217 mutation carriers, 10 (45%) males and 12 (55%) females. The mean age at diagnosis was 59.8 years (range 39.2-74.3 years). Revision of the MRI/MRCP revealed a lesion and dilatation of the MPD in 8 of the 22 patients. In 5 of 7 patients with PDAC detected during follow-up, the previous MRI showed MPD dilatation without evidence of tumor. The mean size of PDAC was 12.3 mm (range 5-19 mm). All tumors were resectable. CONCLUSION: MPD dilation is common in patients with screen-detected PDAC. Abnormalities on MRI during surveillance of high-risk individuals requires intense follow-up or prompt treatment, as early treatment results in a better prognosis.

Spatial pattern analysis of nuclear migration in remodelled muscles during Drosophila metamorphosis.

BACKGROUND: Many human muscle wasting diseases are associated with abnormal nuclear localization. During metamorphosis in Drosophila melanogaster, multi-nucleated larval dorsal abdominal muscles either undergo cell death or are remodeled to temporary adult muscles. Muscle remodeling is associated with anti-polar nuclear migration and atrophy during early pupation followed by polar migration and muscle growth during late pupation. Muscle remodeling is a useful model to study genes involved in myonuclear migration. Previously, we showed that loss of Cathepsin-L inhibited anti-polar movements, while knockdown of autophagy-related genes affected nuclear positioning along the medial axis in late metamorphosis. RESULTS: To compare the phenotypic effects of gene perturbations on nuclear migration more objectively, we developed new descriptors of myonuclear distribution. To obtain nuclear pattern features, we designed an algorithm to detect and track nuclear regions inside live muscles. Nuclear tracks were used to distinguish between fast moving nuclei associated with fragments of dead muscles (sarcolytes) and slow-moving nuclei inside remodelled muscles. Nuclear spatial pattern features, such as longitudinal (lonNS) and lateral nuclear spread (latNS), allowed us to compare nuclear migration during muscle remodelling in different genetic backgrounds. Anti-polar migration leads to a lonNS decrease. As expected, lack of myonuclear migration caused by the loss of Cp1 was correlated with a significantly lower lonNS decrease. Unexpectedly, the decrease in lonNS was significantly enhanced by Atg9, Atg5 and Atg18 silencing, indicating that the loss of autophagy promotes the migration and clustering of nuclei. Loss of autophagy also caused a scattering of nuclei along the lateral axis, leading to a two-row as opposed to single row distribution in control muscles. Increased latNS resulting from knockdown of Atg9 and Atg18 was correlated with increased muscle diameter, suggesting that the wider muscle fibre promotes lateral displacement of nuclei from the medial axis during polar migration. CONCLUSIONS: We developed new nuclear features to characterize the dynamics of nuclear distribution in time-lapse images of Drosophila metamorphosis. Image quantification improved our understanding of phenotypic abnormalities in nuclear distribution resulting from gene perturbations. Therefore, in vivo imaging and quantitative image analysis of Drosophila metamorphosis promise to provide novel insights into the relationship between muscle wasting and myonuclear positioning.

Live imaging of muscles in Drosophila metamorphosis: Towards high-throughput gene identification and function analysis.

Time-lapse microscopy in developmental biology is an emerging tool for functional genomics. Phenotypic effects of gene perturbations can be studied non-invasively at multiple time points in chronological order. During metamorphosis of Drosophila melanogaster, time-lapse microscopy using fluorescent reporters allows visualization of alternative fates of larval muscles, which are a model for the study of genes related to muscle wasting. While doomed muscles enter hormone-induced programmed cell death, a smaller population of persistent muscles survives to adulthood and undergoes morphological remodeling that involves atrophy in early, and hypertrophy in late pupation. We developed a method that combines in vivo imaging, targeted gene perturbation and image analysis to identify and characterize genes involved in muscle development. Macrozoom microscopy helps to screen for interesting muscle phenotypes, while confocal microscopy in multiple locations over 4-5 days produces time-lapse images that are used to quantify changes in cell morphology. Performing a similar investigation using fixed pupal tissues would be too time-consuming and therefore impractical. We describe three applications of our pipeline. First, we show how quantitative microscopy can track and measure morphological changes of muscle throughout metamorphosis and analyze genes involved in atrophy. Second, our assay can help to identify genes that either promote or prevent histolysis of abdominal muscles. Third, we apply our approach to test new fluorescent proteins as live markers for muscle development. We describe mKO2 tagged Cysteine proteinase 1 (Cp1) and Troponin-I (TnI) as examples of proteins showing developmental changes in subcellular localization. Finally, we discuss strategies to improve throughput of our pipeline to permit genome-wide screens in the future.

Live imaging of muscle histolysis in Drosophila metamorphosis.

BACKGROUND: The contribution of programmed cell death (PCD) to muscle wasting disorders remains a matter of debate. Drosophila melanogaster metamorphosis offers the opportunity to study muscle cell death in the context of development. Using live cell imaging of the abdomen, two groups of larval muscles can be observed, doomed muscles that undergo histolysis and persistent muscles that are remodelled and survive into adulthood. METHOD: To identify and characterize genes that control the decision between survival and cell death of muscles, we developed a method comprising in vivo imaging, targeted gene perturbation and time-lapse image analysis. Our approach enabled us to study the cytological and temporal aspects of abnormal cell death phenotypes. RESULTS: In a previous genetic screen for genes controlling muscle size and cell death in metamorphosis, we identified gene perturbations that induced cell death of persistent or inhibit histolysis of doomed larval muscles. RNA interference (RNAi) of the genes encoding the helicase Rm62 and the lysosomal Cathepsin-L homolog Cysteine proteinase 1 (Cp1) caused premature cell death of persistent muscle in early and mid-pupation, respectively. Silencing of the transcriptional co-repressor Atrophin inhibited histolysis of doomed muscles. Overexpression of dominant-negative Target of Rapamycin (TOR) delayed the histolysis of a subset of doomed and induced ablation of all persistent muscles. RNAi of AMPKα, which encodes a subunit of the AMPK protein complex that senses AMP and promotes ATP formation, led to loss of attachment and a spherical morphology. None of the perturbations affected the survival of newly formed adult muscles, suggesting that the method is useful to find genes that are crucial for the survival of metabolically challenged muscles, like those undergoing atrophy. The ablation of persistent muscles did not affect eclosion of adult flies. CONCLUSIONS: Live imaging is a versatile approach to uncover gene functions that are required for the survival of muscle undergoing remodelling, yet are dispensable for other adult muscles. Our approach promises to identify molecular mechanisms that can explain the resilience of muscles to PCD.

Allogeneic Bone Marrow-Derived Mesenchymal Stromal Cells Promote Healing of Refractory Perianal Fistulas in Patients With Crohn's Disease.

BACKGROUND & AIMS: Patients with perianal fistulizing Crohn's disease have a poor prognosis because these lesions do not heal well. We evaluated the effects of local administration of bone marrow-derived mesenchymal stromal cells (MSCs) to these patients from healthy donors in a double-blind, placebo-controlled study. METHODS: Twenty-one patients with refractory perianal fistulizing Crohn's disease were randomly assigned to groups given injections of 1 × 10(7) (n = 5, group 1), 3 × 10(7) (n = 5, group 2), or 9 × 10(7) (n = 5, group 3) MSCs, or placebo (solution with no cells, n = 6), into the wall of curettaged fistula, around the trimmed and closed internal opening. The primary outcome, fistula healing, was determined by physical examination 6, 12, and 24 weeks later; healing was defined as absence of discharge and <2 cm of fluid collection-the latter determined by magnetic resonance imaging at week 12. All procedures were performed at Leiden University Medical Center, The Netherlands, from June 2012 through July 2014. RESULTS: No adverse events were associated with local injection of any dose of MSCs. Healing at week 6 was observed in 3 patients in group 1 (60.0%), 4 patients in group 2 (80.0%), and 1 patient in group 3 (20.0%), vs 1 patient in the placebo group (16.7%) (P = .08 for group 2 vs placebo). At week 12, healing was observed in 2 patients in group 1 (40.0%), 4 patients in group 2 (80.0%), and 1 patient in group 3 (20.0%), vs 2 patients in the placebo group (33.3%); these effects were maintained until week 24 and even increased to 4 (80.0%) in group 1. At week six, 4 of 9 individual fistulas had healed in group 1 (44.4%), 6 of 7 had healed in group 2 (85.7%), and 2 of 7 had healed in group 3 (28.6%) vs 2 of 9 (22.2%) in the placebo group (P = .04 for group 2 vs placebo). At week twelve, 3 of 9 individual fistulas had healed in group 1 (33.3%), 6 of 7 had healed in group 2 (85.7%), 2 of 7 had healed in group 3 (28.6%), and 3 of 9 had healed in the placebo group (33.3%). These effects were stable through week 24 and even increased to 6 of 9 (66.7%) in group 1 (P = .06 group 2 vs placebo, weeks 12 and 24). CONCLUSIONS: Local administration of allogeneic MSCs was not associated with severe adverse events in patients with perianal fistulizing Crohn's disease. Injection of 3 × 10(7) MSCs appeared to promote healing of perianal fistulas. ClinicalTrials.gov ID NCT01144962.

Cyclin-dependent kinase 1 (Cdk1) is essential for cell division and suppression of DNA re-replication but not for liver regeneration.

Cyclin-dependent kinase 1 (Cdk1) is an archetypical kinase and a central regulator that drives cells through G2 phase and mitosis. Knockouts of Cdk2, Cdk3, Cdk4, or Cdk6 have resulted in viable mice, but the in vivo functions of Cdk1 have not been fully explored in mammals. Here we have generated a conditional-knockout mouse model to study the functions of Cdk1 in vivo. Ablation of Cdk1 leads to arrest of embryonic development around the blastocyst stage. Interestingly, liver-specific deletion of Cdk1 is well tolerated, and liver regeneration after partial hepatectomy is not impaired, indicating that regeneration can be driven by cell growth without cell division. The loss of Cdk1 does not affect S phase progression but results in DNA re-replication because of an increase in Cdk2/cyclin A2 activity. Unlike other Cdks, loss of Cdk1 in the liver confers complete resistance against tumorigenesis induced by activated Ras and silencing of p53.

FMAj: a tool for high content analysis of muscle dynamics in Drosophila metamorphosis.

BACKGROUND: During metamorphosis in Drosophila melanogaster, larval muscles undergo two different developmental fates; one population is removed by cell death, while the other persistent subset undergoes morphological remodeling and survives to adulthood. Thanks to the ability to perform live imaging of muscle development in transparent pupae and the power of genetics, metamorphosis in Drosophila can be used as a model to study the regulation of skeletal muscle mass. However, time-lapse microscopy generates sizeable image data that require new tools for high throughput image analysis. RESULTS: We performed targeted gene perturbation in muscles and acquired 3D time-series images of muscles in metamorphosis using laser scanning confocal microscopy. To quantify the phenotypic effects of gene perturbations, we designed the Fly Muscle Analysis tool (FMAj) which is based on the ImageJ and MySQL frameworks for image processing and data storage, respectively. The image analysis pipeline of FMAj contains three modules. The first module assists in adding annotations to time-lapse datasets, such as genotypes, experimental parameters and temporal reference points, which are used to compare different datasets. The second module performs segmentation and feature extraction of muscle cells and nuclei. Users can provide annotations to the detected objects, such as muscle identities and anatomical information. The third module performs comparative quantitative analysis of muscle phenotypes. We applied our tool to the phenotypic characterization of two atrophy related genes that were silenced by RNA interference. Reduction of Drosophila Tor (Target of Rapamycin) expression resulted in enhanced atrophy compared to control, while inhibition of the autophagy factor Atg9 caused suppression of atrophy and enlarged muscle fibers of abnormal morphology. FMAj enabled us to monitor the progression of atrophic and hypertrophic phenotypes of individual muscles throughout metamorphosis. CONCLUSIONS: We designed a new tool to visualize and quantify morphological changes of muscles in time-lapse images of Drosophila metamorphosis. Our in vivo imaging experiments revealed that evolutionarily conserved genes involved in Tor signalling and autophagy, perform similar functions in regulating muscle mass in mammals and Drosophila. Extending our approach to a genome-wide scale has the potential to identify new genes involved in muscle size regulation.

Doxycycline for stabilization of abdominal aortic aneurysms: a randomized trial.

BACKGROUND: Doxycycline inhibits formation and progression of abdominal aortic aneurysms (AAAs) in preclinical models of the disease, but it is unclear whether and how this observation translates to humans. OBJECTIVE: To test whether doxycycline inhibits AAA progression in humans. DESIGN: Randomized, placebo-controlled, double-blind trial. (Dutch Trial Registry: NTR 1345) SETTING: 14 Dutch hospitals. PATIENTS: 286 patients with small AAAs between October 2008 and June 2011. INTERVENTION: Daily dose of 100 mg of doxycycline (n = 144) or placebo (n = 142) for 18 months. MEASUREMENTS: The primary outcome measure was aneurysm growth at 18 months, as estimated by repeated single-observer ultrasonography. Secondary outcomes included growth at 6 and 12 months and the need for elective surgery. RESULTS: Mean aneurysm diameter (approximately 43 mm) and other baseline characteristics were similar in both groups. Doxycycline treatment was associated with increased aneurysm growth (4.1 mm in the doxycycline group vs. 3.3 mm in the placebo group at 18 months; difference, 0.8 mm [95% CI, 0.1 to 1.4 mm]; P = 0.016 mm). Twenty-one patients receiving doxycycline and 22 patients receiving placebo had elective surgical repair (Kaplan­Meier estimates were 16.1% for those receiving doxycycline and 16.5% for those receiving placebo; difference, -0.4% [CI, -9.3% to 8.5%]; P = 0.83). Time to repair was similar in the groups (P = 0.92). LIMITATIONS: This study focuses on patients with small AAAs. As such, whether the data can be extrapolated to larger AAAs (>55 mm) is unclear. The high number of elective repairs (n = 43) was unanticipated. Moreover, the study did not follow patients who withdrew because of an adverse effect. CONCLUSION: This trial found that 18 months of doxycycline therapy did not reduce aneurysm growth and did not influence the need for AAA repair or time to repair. PRIMARY FUNDING SOURCE: The Netherlands Organisation for Health Research and Development, and the NutsOhra Fund.

Aspects and outcomes of surveillance for individuals at high-risk of pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) is a leading cause of cancer-related deaths and is associated with a poor prognosis. The majority of these cancers are detected at a late stage, contributing to the bad prognosis. This underscores the need for novel, enhanced early detection strategies to improve the outcomes. While population-based screening is not recommended due to the relatively low incidence of PDAC, surveillance is recommended for individuals at high risk for PDAC due to their increased incidence of the disease. However, the outcomes of pancreatic cancer surveillance in high-risk individuals are not sorted out yet. In this review, we will address the identification of individuals at high risk for PDAC, discuss the objectives and targets of surveillance, outline how surveillance programs are organized, summarize the outcomes of high-risk individuals undergoing pancreatic cancer surveillance, and conclude with a future perspective on pancreatic cancer surveillance and novel developments.