Metavert synergises with standard cytotoxics in human PDAC organoids and is associated with transcriptomic signatures of therapeutic response.

BACKGROUND: Despite some recent advances, pancreatic ductal adenocarcinoma (PDAC) remains a growing oncological challenge. New drugs capable of targeting more than one oncogenic pathway may be one way to improve patient outcomes. This study characterizes the effectiveness of Metavert a first-in-class dual inhibitor of GSK3-ß and histone deacetylase in treating PDAC as a single agent or in combination with standard cytotoxics. METHODS: Thirty-six Patient-Derived Organoids (hPDOs) characterised by RNASeq and whole exome sequencing were treated with Metavert alone or in combination with standard cytotoxics. Transcriptomic signatures (TS) representing sensitivity to Metavert alone or sensitivity to Metavert + irinotecan (IR) were evaluated in 47 patient samples, chemo-naïve in 26 and post-chemotherapy in 21 (gemcitabine=5; FOLFIRINOX=14, both=2) with companion multiplexed immunofluorescence and RNASeq data. RESULTS: Metavert combined with gemcitabine, irinotecan, 5FU, oxaliplatin, and paclitaxel was synergistic in the hPDOs. Basal-subtype hPDOs were more sensitive to Metavert alone whereas the Metavert+IR combination exhibited synergy in Classical-subtype hPDOs with increased apoptosis and autophagy. hPDO-derived TS evaluated in PDAC tissues demonstrated that Metavert-TSHi samples were enriched for mRNA splicing and DNA repair processes; they were associated with Basal-like tissues but also with GATA6+ve-chemo-naïve samples and were higher following gemcitabine but not FOLFIRINOX treatment. In contrast, Metavert+IR-TSHI samples were enriched for TP53 pathways; they were associated with Classical-like pretreatment samples and with GATA6+ve/KRT17+ve hybrid cell types following FOLFIRINOX, but not gemcitabine treatment, and were unrelated to transcriptional subtypes. CONCLUSIONS: Metavert as a single agent and in combination with irinotecan offers novel strategies for treating pancreatic cancer.

Who Do We Fail to Rescue after Pancreatoduodenectomy? Outcomes Among >4000 Procedures Expose Windows of Opportunity.

OBJECTIVE: Our investigation on in-hospital mortality after 4474 pancreatoduodenectomies aimed to identify time-dependent risks as well as windows of opportunity to rescue patients from complications. BACKGROUND: Pancreatoduodenectomy is generally considered a safe procedure with a 1-10% perioperative mortality based on complexity and surgical volume. Yet, patients are susceptible for life-threatening complications particularly with extended resections. Recognition of distinct vulnerabilities over time while patients recover is required to permit focused monitoring, sophisticated resource allocation, and greatest surgical safety. METHODS: Patients who deceased in-hospital after pancreatoduodenectomy between 2003-2021 were retrieved from the institutional pancreatectomy registry and analyzed in detail with respect to their postoperative course. RESULTS: Among 4474 pancreatoduodenectomies, 156 patients deceased in-hospital (3.5%). When assessing root causes of mortality, we observed 3 different clusters of complications which were postpancreatectomy-specific (47.4%), visceral vasculature-associated (25.6%), or cardiopulmonary in origin (23.7%). The median times of root cause onset in the 3 categories were postoperative day (POD) 9, POD 4.5 ( P =0.008) and POD 3 ( P <0.001), and medians of in-hospital mortality were POD 31, POD 18 ( P =0.009) and POD 8 ( P <0.001), respectively. Intervals between root cause onset and mortality varied with medians of 23 days, 11 days ( P =0.017), and 1 days ( P <0.001). The 3 categories were similarly distributed between different types of surgical complexity. CONCLUSION: Postpancreatectomy-specific complications prompt almost half of in-hospital mortalities after pancreatoduodenectomy, with rather long intervals for interventions to prevent failure to rescue. In contrast, visceral vasculature-related events and cardiopulmonary complications dominate early in-hospital mortalities with short intervals until mortality, demanding rigorous management of such events or preoperative conditioning. These data externally validate a previous high-volume initiative and highlight distinct windows of opportunity to optimize perioperative safety.

A 5:2 intermittent fasting regimen ameliorates NASH and fibrosis and blunts HCC development via hepatic PPARα and PCK1.

The role and molecular mechanisms of intermittent fasting (IF) in non-alcoholic steatohepatitis (NASH) and its transition to hepatocellular carcinoma (HCC) are unknown. Here, we identified that an IF 5:2 regimen prevents NASH development as well as ameliorates established NASH and fibrosis without affecting total calorie intake. Furthermore, the IF 5:2 regimen blunted NASH-HCC transition when applied therapeutically. The timing, length, and number of fasting cycles as well as the type of NASH diet were critical parameters determining the benefits of fasting. Combined proteome, transcriptome, and metabolome analyses identified that peroxisome-proliferator-activated receptor alpha (PPARα) and glucocorticoid-signaling-induced PCK1 act co-operatively as hepatic executors of the fasting response. In line with this, PPARα targets and PCK1 were reduced in human NASH. Notably, only fasting initiated during the active phase of mice robustly induced glucocorticoid signaling and free-fatty-acid-induced PPARα signaling. However, hepatocyte-specific glucocorticoid receptor deletion only partially abrogated the hepatic fasting response. In contrast, the combined knockdown of Ppara and Pck1 in vivo abolished the beneficial outcomes of fasting against inflammation and fibrosis. Moreover, overexpression of Pck1 alone or together with Ppara in vivo lowered hepatic triglycerides and steatosis. Our data support the notion that the IF 5:2 regimen is a promising intervention against NASH and subsequent liver cancer.

Distal Pancreatectomy: Extent of Resection Determines Surgical Risk Categories.

BACKGROUND: Recently, subclassification of pancreatoduodenectomy in 4 differing types has been reported, because additional major vascular and multivisceral resections have been shown to be associated with an increased risk of postoperative morbidity and mortality. OBJECTIVE: To classify distal pancreatectomy (DP) based on the extent of resection and technical difficulty and to evaluate postoperative outcomes with regards to this classification system. METHODS: All consecutive patients who had undergone DP between 2001 and 2020 in a high-volume pancreatic surgery center were included in this study. DPs were subclassified into 4 distinct categories reflecting the extent of resection and technical difficulty, including standard DP (type 1), DP with venous (type 2), multivisceral (type 3), or arterial resection (type 4). Patient characteristics, perioperative data, and postoperative outcomes were analyzed and compared among the 4 groups. RESULTS: A total of 2135 patients underwent DP. Standard DP was the most frequently performed procedure (64.8%). The overall 90-day mortality rate was 1.6%. Morbidity rates were higher in patients with additional vascular or multivisceral resections, and 90-day mortality gradually increased with the extent of resection from standard DP to DP with arterial resection (type 1: 0.7%; type 2: 1.3%; type 3: 3%; type 4: 8.7%; P <0.0001). Multivariable analysis confirmed the type of DP as an independent risk factor for 90-day mortality. CONCLUSIONS: Postoperative outcomes after DP depend on the extent of resection and correlate with the type of DP. The implementation of the 4-type classification system allows standardized reporting of surgical outcomes after DP improving comparability of future studies.

Impact of circumferential resection margin on survival in ampullary cancer: retrospective analysis.

BACKGROUND: Ampullary carcinoma is a clinically variable entity. This study aimed to evaluate prognostic factors for the outcome of resected ampullary carcinoma patients with particular intent to analyse the influence of surgical radicality. METHODS: Patients undergoing resection between 2002 and 2017 were analysed. Clinicopathological parameters, perioperative outcome and survival were examined. Risk factor analysis for postresection survival was performed. Resection margin status was evaluated according to the revised classification for pancreatic adenocarcinoma. RESULTS: A total of 234 patients were identified, 97.9 per cent (n = 229) underwent formal resection, while 2.1 per cent (n = 5) underwent ampullary resection. Histological subtypes were 46.6 per cent (n = 109) pancreatobiliary, 34.2 per cent (n = 80) intestinal, 11.5 per cent (n = 27) mixed, and 7.7 per cent (n = 18) undetermined. In the pancreatobiliary group, tumours were more advanced with more vascular resections, pT4 stage, G3 differentiation and pN+ status. Five-year overall survival was significantly different for pancreatobiliary compared to intestinal (51.7 per cent versus 72.8 per cent, P = 0.0087). In univariable analysis, age, pT4 stage, pN+, pancreatobiliary subtype and positive resection margin were significantly associated with worse overall survival. Long-term outcome was significantly better after true R0 resection (circumferential resection margin-, tumour clearance >1 mm) compared with circumferential resection margin+ (<1 mm) and R1 resections (5-year overall survival: 69.6 per cent, median overall survival 191 months versus 42.4 per cent and 53 months; P = 0.0017). CONCLUSION: Postresection survival of ampullary carcinoma patients is determined by histological subtype and surgical radicality. Intestinal differentiation is associated with less advanced tumour stages and better differentiation, which is reflected in a significantly better overall survival compared to pancreatobiliary differentiation. Despite this, true R0-resection is a prognostic key determinant in both entities, achieving 5-year survival in two-thirds of patients.

Successful intra-abdominal resection of a 24 kg ovarian granulosa cell tumor in a Warmblood mare.

Background: Granulosa cell tumors (GCTs) are the most common ovarian tumors in mares. The classical presentation of a GCT is a unilaterally enlarged ovary appearing as a multicystic honeycomb mass. In rare cases, GCTs cause hemoperitoneum as a result of the rapid growth of the tumor. The clinical diagnosis of GCT is usually based on history, rectal examination, ultrasonographic examination, and serum hormone analysis, and surgical removal of the affected ovary is the treatment of choice. The different surgical approaches are based on the dimension of the GCT. Case Description: A 7-year-old mare was referred to the department for horses due to suspicion of a large colon impaction. The mare presented with clinical signs of colic, fever, and signs of hypovolemic shock. Rectal and ultrasonographic examination showed hemoperitoneum and a honey-comb mass within the abdomen, and a GCT as the cause of an acute hemoperitoneum was diagnosed based on the serum level of anti-Müllerian hormone. After stabilization of the mare, the GCT was removed through a ventral midline incision. Because of the enormous dimensions of the GCT, intra-abdominal partial resection of the tumor using a tenotomy knife was necessary to exteriorize the ovarian pedicle. At 3 months follow-up, the mare was ridden for her intended use. Conclusion: This report provides an approach to an uncommon case of a very large and heavy GCT.

Exploring the Neandertal legacy of pancreatic ductal adenocarcinoma risk in Eurasians.

BACKGROUND: The genomes of present-day non-Africans are composed of 1-3% of Neandertal-derived DNA as a consequence of admixture events between Neandertals and anatomically modern humans about 50-60 thousand years ago. Neandertal-introgressed single nucleotide polymorphisms (aSNPs) have been associated with modern human disease-related traits, which are risk factors for pancreatic ductal adenocarcinoma (PDAC), such as obesity, type 2 diabetes, and inflammation. In this study, we aimed at investigating the role of aSNPs in PDAC in three Eurasian populations. RESULTS: The high-coverage Vindija Neandertal genome was used to select aSNPs in non-African populations from 1000 Genomes project phase 3 data. Then, the association between aSNPs and PDAC risk was tested independently in Europeans and East Asians, using existing GWAS data on more than 200 000 individuals. We did not find any significant associations between aSNPs and PDAC in samples of European descent, whereas, in East Asians, we observed that the Chr10p12.1-rs117585753-T allele (MAF = 10%) increased the risk to develop PDAC (OR = 1.35, 95%CI 1.19-1.54, P = 3.59 × 10-6), with a P-value close to a threshold that takes into account multiple testing. CONCLUSIONS: Our results show only a minimal contribution of Neandertal SNPs to PDAC risk.

Spatially Resolved Multi-Omics Single-Cell Analyses Inform Mechanisms of Immune Dysfunction in Pancreatic Cancer.

BACKGROUND & AIMS: As pancreatic ductal adenocarcinoma (PDAC) continues to be recalcitrant to therapeutic interventions, including poor response to immunotherapy, albeit effective in other solid malignancies, a more nuanced understanding of the immune microenvironment in PDAC is urgently needed. We aimed to unveil a detailed view of the immune micromilieu in PDAC using a spatially resolved multimodal single-cell approach. METHODS: We applied single-cell RNA sequencing, spatial transcriptomics, multiplex immunohistochemistry, and mass cytometry to profile the immune compartment in treatment-naïve PDAC tumors and matched adjacent normal pancreatic tissue, as well as in the systemic circulation. We determined prognostic associations of immune signatures and performed a meta-analysis of the immune microenvironment in PDAC and lung adenocarcinoma on single-cell level. RESULTS: We provided a spatially resolved fine map of the immune landscape in PDAC. We substantiated the exhausted phenotype of CD8 T cells and immunosuppressive features of myeloid cells, and highlighted immune subsets with potentially underappreciated roles in PDAC that diverged from immune populations within adjacent normal areas, particularly CD4 T cell subsets and natural killer T cells that are terminally exhausted and acquire a regulatory phenotype. Differential analysis of immune phenotypes in PDAC and lung adenocarcinoma revealed the presence of extraordinarily immunosuppressive subtypes in PDAC, along with a distinctive immune checkpoint composition. CONCLUSIONS: Our study sheds light on the multilayered immune dysfunction in PDAC and presents a holistic view of the immune landscape in PDAC and lung adenocarcinoma, providing a comprehensive resource for functional studies and the exploration of therapeutically actionable targets in PDAC.

Surgery for intraductal papillary mucinous neoplasms in young patients: High-risk population.

BACKGROUND: Intraductal papillary mucinous neoplasms of the pancreas are uncommon in young individuals. Management of these patients is challenging because the risk of malignancy and recurrence after surgery remains unclear. The aim of the present study was to assess the long-term risk for intraductal papillary mucinous neoplasm recurrence after surgery for intraductal papillary mucinous neoplasms in patients ≤50 years of age. METHODS: Perioperative and long-term follow-up data of patients who had undergone surgery for intraductal papillary mucinous neoplasms between 2004 and 2020 were extracted from a prospective unicentric database and retrospectively analyzed. RESULTS: Seventy-eight patients underwent surgical treatment for benign intraductal papillary mucinous neoplasms (low-grade n = 22 and intermediate-grade n = 21) and malignant intraductal papillary mucinous neoplasms (high-grade n = 16 and intraductal papillary mucinous neoplasm-associated carcinoma n = 19). Severe postoperative morbidity (Clavien-Dindo ≥III) was found in 14 patients (18%). The median length of hospital stay was 10 days. No perioperative mortality was observed. The median length of follow-up was 72 months. Recurrence of intraductal papillary mucinous neoplasm-associated carcinoma was found in 6 patients (19%) with malignant intraductal papillary mucinous neoplasm and 1 patient (3%) with benign intraductal papillary mucinous neoplasm. CONCLUSION: Surgery for intraductal papillary mucinous neoplasm is safe and can be performed with low morbidity and potentially no mortality in young patients. Given the high rate of malignancy (45%), these patients with intraductal papillary mucinous neoplasms represent a high-risk population, and prophylactic surgical treatment should be considered in these patients with long life expectancies. Regular clinical and radiologic follow-up examinations are important to rule out disease recurrence, which is high, especially in patients with intraductal papillary mucinous neoplasm-associated carcinoma.

Corrigendum: Clinical impact of molecular subtyping of pancreatic cancer.

[This corrects the article DOI: 10.3389/fcell.2021.743908.].

Plasma extracellular vesicle messenger RNA profiling identifies prognostic EV signature for non-invasive risk stratification for survival prediction of patients with pancreatic ductal adenocarcinoma.

BACKGROUND: The prognosis of pancreatic ductal adenocarcinoma (PDAC) is one of the most dismal of all cancers and the median survival of PDAC patients is only 6-8 months after diagnosis. While decades of research effort have been focused on early diagnosis and understanding of molecular mechanisms, few clinically useful markers have been universally applied. To improve the treatment and management of PDAC, it is equally relevant to identify prognostic factors for optimal therapeutic decision-making and patient survival. Compelling evidence have suggested the potential use of extracellular vesicles (EVs) as non-invasive biomarkers for PDAC. The aim of this study was thus to identify non-invasive plasma-based EV biomarkers for the prediction of PDAC patient survival after surgery. METHODS: Plasma EVs were isolated from a total of 258 PDAC patients divided into three independent cohorts (discovery, training and validation). RNA sequencing was first employed to identify differentially-expressed EV mRNA candidates from the discovery cohort (n = 65) by DESeq2 tool. The candidates were tested in a training cohort (n = 91) by digital droplet polymerase chain reaction (ddPCR). Cox regression models and Kaplan-Meier analyses were used to build an EV signature which was subsequently validated on a multicenter cohort (n = 83) by ddPCR. RESULTS: Transcriptomic profiling of plasma EVs revealed differentially-expressed mRNAs between long-term and short-term PDAC survivors, which led to 10 of the top-ranked candidate EV mRNAs being tested on an independent training cohort with ddPCR. The results of ddPCR enabled an establishment of a novel prognostic EV mRNA signature consisting of PPP1R12A, SCN7A and SGCD for risk stratification of PDAC patients. Based on the EV mRNA signature, PDAC patients with high risk displayed reduced overall survival (OS) rates compared to those with low risk in the training cohort (p = 0.014), which was successfully validated on another independent cohort (p = 0.024). Interestingly, the combination of our signature and tumour stage yielded a superior prognostic performance (p = 0.008) over the signature (p = 0.022) or tumour stage (p = 0.016) alone. It is noteworthy that the EV mRNA signature was demonstrated to be an independent unfavourable predictor for PDAC prognosis. CONCLUSION: This study provides a novel and non-invasive prognostic EV mRNA signature for risk stratification and survival prediction of PDAC patients.

Cancer-educated mammary adipose tissue-derived stromal/stem cells in obesity and breast cancer: spatial regulation and function.

BACKGROUND: Breast cancer is the most frequently diagnosed cancer and a common cause of cancer-related death in women. It is well recognized that obesity is associated with an enhanced risk of more aggressive breast cancer as well as reduced patient survival. Breast adipose tissue-derived mesenchymal stromal/stem cells (bASCs) are crucial components of the tumor microenvironment. A key step initially involved in this process might be the de-differentiation of bASCs into tumor supporting phenotypes. METHODS: In the present work, we isolated bASCs from adipose tissues adjacent to the tumor (aT bASCs) from lean- (ln-aT bASCs, BMI ≤ 25) and breast cancer patients with obesity (ob-aT bASCs, BMI ≥ 35), and analyzed their phenotypes with functional assays and RNA sequencing, compared to their counterparts isolated from adipose tissues distant from the tumor (dT bASCs). RESULTS: We show that ln-aT bASCs are susceptible to be transformed into an inflammatory cancer-associated phenotype, whereas ob-aT bASCs are prone to be cancer-educated into a myofibroblastic phenotype. Both ln-aT- and ob-aT bASCs compromise their physiological differentiation capacity, and upregulate metastasis-promoting factors. While ln-aT bASCs stimulate proliferation, motility and chemoresistance by inducing epithelial-mesenchymal transition of low malignant breast cancer cells, ob-aT bASCs trigger more efficiently a cancer stem cell phenotype in highly malignant breast cancer cells. CONCLUSION: Breast cancer-associated bASCs are able to foster malignancy of breast cancer cells by multiple mechanisms, especially, induction of epithelial-mesenchymal transition and activation of stemness-associated genes in breast cancer cells. Blocking the de-differentiation of bASCs in the tumor microenvironment could be a novel strategy to develop an effective intervention for breast cancer patients. SIGNIFICANCE: This study provides mechanistic insights into how obesity affects the phenotype of bASCs in the TME. Moreover, it highlights the molecular changes inside breast cancer cells upon cell-cell interaction with cancer-educated bASCs.

Blood-Based Diagnosis and Risk Stratification of Patients with Pancreatic Intraductal Papillary Mucinous Neoplasm (IPMN).

PURPOSE: Intraductal papillary mucinous neoplasm (IPMN) is a precursor of pancreatic ductal adenocarcinoma. Low-grade dysplasia has a relatively good prognosis, whereas high-grade dysplasia and IPMN invasive carcinoma require surgical intervention. However, diagnostic distinction is difficult. We aimed to identify biomarkers in peripheral blood for accurate discrimination. EXPERIMENTAL DESIGN: Sera were obtained from 302 patients with IPMNs and 88 healthy donors. For protein biomarkers, serum samples were analyzed on microarrays made of 2,977 antibodies. A support vector machine (SVM) algorithm was applied to define classifiers, which were validated on a separate sample set. For microRNA biomarkers, a PCR-based screen was performed for discovery. Biomarker candidates confirmed by quantitative PCR were used to train SVM classifiers, followed by validation in a different sample set. Finally, a combined SVM classifier was established entirely independent of the earlier analyses, again using different samples for training and validation. RESULTS: Panels of 26 proteins or seven microRNAs could distinguish high- and low-risk IPMN with an AUC value of 95% and 94%, respectively. Upon combination, a panel of five proteins and three miRNAs yielded an AUC of 97%. These values were much better than those obtained in the same patient cohort by using the guideline criteria for discrimination. In addition, accurate discrimination was achieved between other patient subgroups. CONCLUSIONS: Protein and microRNA biomarkers in blood allow precise diagnosis and risk stratification of IPMN cases, which should improve patient management and thus the prognosis of IPMN patients. See related commentary by Löhr and Pantel, p. 1387.

Genetically Determined Telomere Length Is Associated with Pancreatic Neuroendocrine Neoplasms Onset.

INTRODUCTION: Telomere length (TL) is a potential indicator of cancer predisposition; however, the multitude of techniques used to measure it causes the results to be heterogeneous and, in some cases, controversial. In the last years, several studies adopted a strategy based on TL-associated genetic variants to generate a polygenic score, often referred as teloscore, used in lieu of direct TL measurement. For pancreatic neuroendocrine neoplasms (PanNEN), this strategy has not been attempted yet. METHODS: A teloscore was generated using 11 SNPs (NAF1-rs7675998, ZNF676-rs409627, TERC-rs10936599, CTC1-rs3027234, PXK-rs6772228, DHX35-rs6028466, OBFC1-rs9420907, ZNF208-rs8105767, ACYP2-rs11125529, TERT-rs2736100, and ZBTB46-rs755017), and 291 PanNEN cases and 1,686 controls collected by the PANcreatic Disease ReseArch (PANDoRA) consortium were genotyped to analyse the association of the teloscore and its individual SNPs with the risk of developing PanNEN. RESULTS: An association between genetically determined long telomeres and the risk of developing PanNEN (OR = 1.99, CI: 1.33-2.98, p = 0.0008) for highest versus median (third) quintile was observed. In addition, two novel SNPs associated with PanNEN risk were identified: ZNF676-rs409627 (ORC/C_vs_G/G = 2.27, CI: 1.58-3.27, p = 8.80 × 10-6) and TERT-rs2736100 (ORC/A_vs_C/C = 2.03, CI: 1.42-2.91, p = 1.06 × 10-4). CONCLUSION: In conclusion, this study provides for the first time a clear indication of the association between long genetically determined telomeres and increased risk of developing PanNEN.

Sca-1 is a marker for cell plasticity in murine pancreatic epithelial cells and induced by IFN-ß in vitro.

BACKGROUND & AIMS: Sca-1 is a surface marker for murine hematopoietic stem cells (HSCs) and type-I interferon is a key regulator for Lin-Sca-1+ HSCs expansion through Ifnar/Stat-1/Sca-1-signaling. In this study we aimed to characterize the role and regulation of Sca-1+ cells in pancreatic regeneration. METHODS: To characterize Sca-1 in vivo, immunohistochemistry and immunofluorescence staining of Sca-1 was conducted in normal pancreas, in cerulein-mediated acute pancreatitis, and in Kras-triggered cancerous lesions. Ifnar/Stat-1/Sca-1-signaling was studied in type-I IFN-treated epithelial explants of adult wildtype, Ifnar-/-, and Stat-1-/- mice. Sca-1 induction was analyzed by gene expression and FACS analysis. After isolation of pancreatic epithelial Lin-Sca-1+cells, pancreatosphere-formation and immunofluorescence-assays were carried out to investigate self-renewal and differentiation capabilities. RESULTS: Sca-1+ cells were located in periacinar and periductal spaces and showed an enrichment during cerulein-induced acute pancreatitis (23.2/100 µm2 ± 4.9 SEM) and in early inflammation-mediated carcinogenic lesions of the pancreas of KrasG12D mice (35.8/100 µm2 ± SEM 1.9) compared to controls (3.6/100 µm2 ± 1.3 SEM). Pancreatic Lin-Sca-1+ cells displayed a small population of 1.46% ± 0.12 SEM in FACS. In IFN-ß treated pancreatic epithelial explants, Sca-1 expression was increased, and Lin-Sca-1+ cells were enriched in vitro (from 1.49% ± 0.36 SEM to 3.85% ± 0.78 SEM). Lin-Sca-1+ cells showed a 12 to 51-fold higher capacity for clonal self-renewal compared to Lin-Sca-1- cells and generated cells express markers of the acinar and ductal compartment. CONCLUSIONS: Pancreatic Sca-1+ cells enriched during parenchymal damage showed a significant capacity for cell renewal and in vitro plasticity, suggesting that corresponding to the type I interferon-dependent regulation of Lin-Sca-1+ hematopoietic stem cells, pancreatic Sca-1+ cells also employ type-I-interferon for regulating progenitor-cell-homeostasis.

Human placental mesenchymal stromal cells are ciliated and their ciliation is compromised in preeclampsia.

BACKGROUND: The development of the human placenta is tightly coordinated by a multitude of placental cell types, including human chorionic villi mesenchymal stromal cells (hCV-MSCs). Defective hCV-MSCs have been reported in preeclampsia (PE), a gestational hypertensive disease characterized by maternal endothelial dysfunction and systemic inflammation. Our goal was to determine whether hCV-MSCs are ciliated and whether altered ciliation is responsible for defective hCV-MSCs in preeclamptic placentas, as the primary cilium is a hub for signal transduction, which is important for various cellular activities. METHODS: In the present work, we collected placental tissues from different gestational stages and we isolated hCV-MSCs from 1st trimester, term control, and preeclamptic placentas. We studied their ciliation, functionality, and impact on trophoblastic cell lines and organoids formed from human trophoblast stem cells (hTSCs) and from the trophoblastic cell line JEG-3 with various cellular and molecular methods, including immunofluorescence staining, gene analysis, spheroid/organoid formation, motility, and cellular network formation assay. The statistical evaluation was performed using a Student's t test (two-tailed and paired or homoscedastic) or an unpaired Mann-Whitney U test (two-tailed). RESULTS: The results show that primary cilia appeared abundantly in normal hCV-MSCs, especially in the early development of the placenta. Compared to control hCV-MSCs, the primary cilia were truncated, and there were fewer ciliated hCV-MSCs derived from preeclamptic placentas with impaired hedgehog signaling. Primary cilia are necessary for hCV-MSCs' proper signal transduction, motility, homing, and differentiation, which are impaired in preeclamptic hCV-MSCs. Moreover, hCV-MSCs derived from preeclamptic placentas are significantly less capable of promoting growth and differentiation of placental organoids, as well as cellular network formation. CONCLUSIONS: These data suggest that the primary cilium is required for the functionality of hCV-MSCs and primary cilia are impaired in hCV-MSCs from preeclamptic placentas.

Mitotic Centromere-Associated Kinesin (MCAK/KIF2C) Regulates Cell Migration and Invasion by Modulating Microtubule Dynamics and Focal Adhesion Turnover.

The microtubule (MT) cytoskeleton is crucial for cell motility and migration by regulating multiple cellular activities such as transport and endocytosis of key components of focal adhesions (FA). The kinesin-13 family is important in the regulation of MT dynamics and the best characterized member of this family is the mitotic centromere-associated kinesin (MCAK/KIF2C). Interestingly, its overexpression has been reported to be related to increased metastasis in various tumor entities. Moreover, MCAK is involved in the migration and invasion behavior of various cell types. However, the precise molecular mechanisms were not completely clarified. To address these issues, we generated CRISPR/dCas9 HeLa and retinal pigment epithelium (RPE) cell lines overexpressing or downregulating MCAK. Both up- or downregulation of MCAK led to reduced cell motility and poor migration in malignant as well as benign cells. Specifically, it's up- or downregulation impaired FA protein composition and phosphorylation status, interfered with a proper spindle and chromosome segregation, disturbed the assembly and disassembly rate of FA, delayed cell adhesion, and compromised the plus-tip dynamics of MTs. In conclusion, our data suggest MCAK act as an important regulator for cell motility and migration by affecting the actin-MT cytoskeleton dynamics and the FA turnover, providing molecular mechanisms by which deregulated MCAK could promote malignant progression and metastasis of tumor cells.

Clinical Impact of Molecular Subtyping of Pancreatic Cancer.

Pancreatic ductal adenocarcinoma is a highly lethal malignancy, which has now become the seventh most common cause of cancer death in the world, with the highest mortality rates in Europe and North America. In the past 30 years, there has been some progress in 5-year survival (rates increasing from 2.5 to 10%), but this is still extremely poor compared to all other common cancer types. Targeted therapies for advanced pancreatic cancer based on actionable mutations have been disappointing, with only 3-5% showing even a short clinical benefit. There is, however, a molecular diversity beyond mutations in genes responsible for producing classical canonical signaling pathways. Pancreatic cancer is almost unique in promoting an excess production of other components of the stroma, resulting in a complex tumor microenvironment that contributes to tumor development, progression, and response to treatment. Various transcriptional subtypes have also been described. Most notably, there is a strong alignment between the Classical/Pancreatic progenitor and Quasi-mesenchymal/Basal-like/Squamous subtype signatures of Moffit, Collinson, Bailey, Puleo, and Chan-Seng-Yue, which have potential clinical impact. Sequencing of epithelial cell populations enriched by laser capture microscopy combined with single-cell RNA sequencing has revealed the potential genomic evolution of pancreatic cancer as being a consequence of a gene expression continuum from mixed Basal-like and Classical cell populations within the same tumor, linked to allelic imbalances in mutant KRAS, with metastatic tumors being more copy number-unstable compared to primary tumors. The Basal-like subtype appears more chemoresistant with reduced survival compared to the Classical subtype. Chemotherapy and/or chemoradiation will also enrich the Basal-like subtype. Squamous/Basal-like programs facilitate immune infiltration compared with the Classical-like programs. The immune infiltrates associated with Basal and Classical type cells are distinct, potentially opening the door to differential strategies. Single-cell and spatial transcriptomics will now allow single cell profiling of tumor and resident immune cell populations that may further advance subtyping. Multiple clinical trials have been launched based on transcriptomic response signatures and molecular subtyping including COMPASS, Precision Promise, ESPAC6/7, PREDICT-PACA, and PASS1. We review several approaches to explore the clinical relevance of molecular profiling to provide optimal bench-to-beside translation with clinical impact.

Association of Genetic Variants Affecting microRNAs and Pancreatic Cancer Risk.

Genetic factors play an important role in the susceptibility to pancreatic cancer (PC). However, established loci explain a small proportion of genetic heritability for PC; therefore, more progress is needed to find the missing ones. We aimed at identifying single nucleotide polymorphisms (SNPs) affecting PC risk through effects on micro-RNA (miRNA) function. We searched in silico the genome for SNPs in miRNA seed sequences or 3 prime untranslated regions (3'UTRs) of miRNA target genes. Genome-wide association data of PC cases and controls from the Pancreatic Cancer Cohort (PanScan) Consortium and the Pancreatic Cancer Case-Control (PanC4) Consortium were re-analyzed for discovery, and genotyping data from two additional consortia (PanGenEU and PANDoRA) were used for replication, for a total of 14,062 cases and 11,261 controls. None of the SNPs reached genome-wide significance in the meta-analysis, but for three of them the associations were in the same direction in all the study populations and showed lower value of p in the meta-analyses than in the discovery phase. Specifically, rs7985480 was consistently associated with PC risk (OR = 1.12, 95% CI 1.07-1.17, p = 3.03 × 10-6 in the meta-analysis). This SNP is in linkage disequilibrium (LD) with rs2274048, which modulates binding of various miRNAs to the 3'UTR of UCHL3, a gene involved in PC progression. In conclusion, our results expand the knowledge of the genetic PC risk through miRNA-related SNPs and show the usefulness of functional prioritization to identify genetic polymorphisms associated with PC risk.