Axon guidance cue SEMA3A promotes the aggressive phenotype of basal-like PDAC

OBJECTIVE

The dysregulation of the axon guidance pathway is common in pancreatic ductal adenocarcinoma (PDAC), yet our understanding of its biological relevance is limited. Here, we investigated the functional role of the axon guidance cue SEMA3A in supporting PDAC progression.

DESIGN

We integrated bulk and single-cell transcriptomic datasets of human PDAC with in situ hybridisation analyses of patients' tissues to evaluate SEMA3A expression in molecular subtypes of PDAC. Gain and loss of function experiments in PDAC cell lines and organoids were performed to dissect how SEMA3A contributes to define a biologically aggressive phenotype.

RESULTS

In PDAC tissues, SEMA3A is expressed by stromal elements and selectively enriched in basal-like/squamous epithelial cells. Accordingly, expression of SEMA3A in PDAC cells is induced by both cell-intrinsic and cell-extrinsic determinants of the basal-like phenotype. In vitro, SEMA3A promotes cell migration as well as anoikis resistance. At the molecular level, these phenotypes are associated with increased focal adhesion kinase signalling through canonical SEMA3A-NRP1 axis. SEMA3A provides mouse PDAC cells with greater metastatic competence and favours intratumoural infiltration of tumour-associated macrophages and reduced density of T cells. Mechanistically, SEMA3A functions as chemoattractant for macrophages and skews their polarisation towards an M2-like phenotype. In SEMA3Ahigh tumours, depletion of macrophages results in greater intratumour infiltration by CD8+T cells and better control of the disease from antitumour treatment.

CONCLUSIONS

Here, we show that SEMA3A is a stress-sensitive locus that promotes the malignant phenotype of basal-like PDAC through both cell-intrinsic and cell-extrinsic mechanisms.

Identification of spatially-resolved markers of malignant transformation in Intraductal Papillary Mucinous Neoplasms

The existing Intraductal Papillary Mucinous Neoplasm (IPMN) risk stratification relies on clinical and histological factors, resulting in inaccuracies and leading to suboptimal treatment. This is due to the lack of appropriate molecular markers that can guide patients toward the best therapeutic options. Here, we assess and confirm subtype-specific markers for IPMN across two independent cohorts of patients using two Spatial Transcriptomics (ST) technologies. Specifically, we identify HOXB3 and ZNF117 as markers for Low-Grade Dysplasia, SPDEF and gastric neck cell markers in borderline cases, and NKX6-2 and gastric isthmus cell markers in High-Grade-Dysplasia Gastric IPMN, highlighting the role of TNFα and MYC activation in IPMN progression and the role of NKX6-2 in the specific Gastric IPMN progression. In conclusion, our work provides a step forward in understanding the gene expression landscapes of IPMN and the critical transcriptional networks related to PDAC progression.

An alternative splicing signature defines the basal-like phenotype and predicts worse clinical outcome in pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is characterized by extremely poor prognosis. PDAC presents with molecularly distinct subtypes, with the basal-like one being associated with enhanced chemoresistance. Splicing dysregulation contributes to PDAC; however, its involvement in subtype specification remains elusive. Herein, we uncover a subtype-specific splicing signature associated with prognosis in PDAC and the splicing factor Quaking (QKI) as a determinant of the basal-like signature. Single-cell sequencing analyses highlight QKI as a marker of the basal-like phenotype. QKI represses splicing events associated with the classical subtype while promoting basal-like events associated with shorter survival. QKI favors a plastic, quasi-mesenchymal phenotype that supports migration and chemoresistance in PDAC organoids and cell lines, and its expression is elevated in high-grade primary tumors and metastatic lesions. These studies identify a splicing signature that defines PDAC subtypes and indicate that QKI promotes an undifferentiated, plastic phenotype, which renders PDAC cells chemoresistant and adaptable to environmental changes.

The Role of the Complement in Clear Cell Renal Carcinoma (ccRCC)-What Future Prospects Are There for Its Use in Clinical Practice?

In recent years, the first-line available therapeutic options for metastatic renal cell carcinoma (mRCC) have radically changed with the introduction into clinical practice of new immune checkpoint inhibitor (ICI)-based combinations. Many efforts are focusing on identifying novel prognostic and predictive markers in this setting. The complement system (CS) plays a central role in promoting the growth and progression of mRCC. In particular, mRCC has been defined as an "aggressive complement tumor", which encompasses a group of malignancies with poor prognosie and highly expressed complement components. Several preclinical and retrospective studies have demonstrated the negative prognostic role of the complement in mRCC; however, there is little evidence on its possible role as a predictor of the response to ICIs. The purpose of this review is to explore more deeply the physio-pathological role of the complement in the development of RCC and its possible future use in clinical practice as a prognostic and predictive factor.

Oncolytic Effect of Zika Virus in Neuroendocrine Pancreatic Tumors: New Perspectives for Therapeutic Approaches

Pancreatic cancer (PCa) is the fifth leading cause of cancer mortality. Recently, our group and others have demonstrated the oncolytic activity of the Zika virus (ZIKV) against glioblastoma. The peculiar features of this virus offer the opportunity to use an agent already tested in vivo through natural transmission, with minimal effects on adults, to specifically target a tumor such as glioblastoma. This remarkable specificity prompted us to explore the potential use of ZIKV oncolytic action against other tumor types. In particular, we focused on the subgroup of pancreatic tumors with a neuroendocrine origin known as neuroendocrine tumors (NETs). We found that ZIKV exerts its oncolytic activity by specifically infecting NET cells, leading to growth inhibition and cell death. We also assessed whether the oncolytic action could be extended to pancreatic tumors different from NETs. However, as expected, the viral specificity is limited to NETs and is not applicable to adenocarcinoma tumors, indicating a narrow spectrum of action for this virus. These findings support the potential use of ZIKV in therapeutic approaches not only in glioblastoma, but also against other tumors, such as neuroendocrine pancreatic tumors.

Talniflumate abrogates mucin immune suppressive barrier improving efficacy of gemcitabine and nab-paclitaxel treatment in pancreatic cancer

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is a lethal disease. This is due to its aggressive course, late diagnosis and its intrinsic drugs resistance. The complexity of the tumor, in terms of cell components and heterogeneity, has led to the approval of few therapies with limited efficacy. The study of the early stages of carcinogenesis provides the opportunity for the identification of actionable pathways that underpin therapeutic resistance.

METHODS

We analyzed 43 Intraductal papillary mucinous neoplasms (IPMN) (12 Low-grade and 31 High-grade) by Spatial Transcriptomics. Mouse and human pancreatic cancer organoids and T cells interaction platforms were established to test the role of mucins expression on T cells activity. Syngeneic mouse model of PDAC was used to explore the impact of mucins downregulation on standard therapy efficacy.

RESULTS

Spatial transcriptomics showed that mucin O-glycosylation pathway is increased in the progression from low-grade to high-grade IPMN. We identified GCNT3, a master regulator of mucins expression, as an actionable target of this pathway by talniflumate. We showed that talniflumate impaired mucins expression increasing T cell activation and recognition using both mouse and human organoid interaction platforms. In vivo experiments showed that talniflumate was able to increase the efficacy of the chemotherapy by boosting immune infiltration.

CONCLUSIONS

Finally, we demonstrated that combination of talniflumate, an anti-inflammatory drug, with chemotherapy effectively improves anti-tumor effect in PDAC.

Leptin-mediated meta-inflammation may provide survival benefit in patients receiving maintenance immunotherapy for extensive-stage small cell lung cancer (ES-SCLC)

BACKGROUND

Only few ES-SCLC patients experience long-term survival benefit by maintenance IT. Adipokines-induced metabolic meta-inflammation has been related to enhanced responsiveness to IT in obese patients; however, their prognostic role in SCLC is currently controversial.

METHODS

Pre-treatment CT scan was used for determining distribution of abdominal adiposity, and blood samples were collected at fasting for measuring glycemia, insulin, ghrelin, leptin and adipokines (TNF-α, IFN-γ, IL-6 and MCP-1). Patients with known history of DM type II or metabolic syndrome with HOMA index > 2.5 were considered insulin resistant (IR).

RESULTS

In ES-SCLC pts receiving maintenance IT, increased leptin concentration and higher leptin/visceral adipose tissue (VAT) ratio were significantly associated with prolonged PFS. By applying a hierarchical clustering algorithm, we identified a cluster of patients characterized by higher leptin values and lower pro-inflammatory cytokines (TNF-α, IFN-γ and IL-6) who experienced longer PFS (13.2 vs 8.05 months; HR: 0.42 [0.18-0.93] p = 0.02) and OS (18.04 vs 12.09 mo; HR: 0.53 [0.25-1.29] p = 0.07).

CONCLUSIONS

Adipokines can play a crucial role to determining effectiveness of anti-cancer immunotherapy. The role of metabolic immune dysfunctions needs further pre-clinical validation and is currently investigated in the larger prospective cohort.

Immune checkpoint blockade therapy mitigates systemic inflammation and affects cellular FLIP-expressing monocytic myeloid-derived suppressor cells in non-progressor non-small cell lung cancer patients

Cancer cells favor the generation of myeloid cells with immunosuppressive and inflammatory features, including myeloid-derived suppressor cells (MDSCs), which support tumor progression. The anti-apoptotic molecule, cellular FLICE (FADD-like interleukin-1β-converting enzyme)-inhibitory protein (c-FLIP), which acts as an important modulator of caspase-8, is required for the development and function of monocytic (M)-MDSCs. Here, we assessed the effect of immune checkpoint inhibitor (ICI) therapy on systemic immunological landscape, including FLIP-expressing MDSCs, in non-small cell lung cancer (NSCLC) patients. Longitudinal changes in peripheral immunological parameters were correlated with patients' outcome. In detail, 34 NSCLC patients were enrolled and classified as progressors (P) or non-progressors (NP), according to the RECIST evaluation. We demonstrated a reduction in pro-inflammatory cytokines such as IL-8, IL-6, and IL-1β in only NP patients after ICI treatment. Moreover, using t-distributed stochastic neighbor embedding (t-SNE) and cluster analysis, we characterized in NP patients a significant increase in the amount of lymphocytes and a slight contraction of myeloid cells such as neutrophils and monocytes. Despite this moderate ICI-associated alteration in myeloid cells, we identified a distinctive reduction of c-FLIP expression in M-MDSCs from NP patients concurrently with the first clinical evaluation (T1), even though NP and P patients showed the same level of expression at baseline (T0). In agreement with the c-FLIP expression, monocytes isolated from both P and NP patients displayed similar immunosuppressive functions at T0; however, this pro-tumor activity was negatively influenced at T1 in the NP patient cohort exclusively. Hence, ICI therapy can mitigate systemic inflammation and impair MDSC-dependent immunosuppression.

Mid-term results of endoscopic mitral valve repair and insights in surgical techniques for isolated posterior prolapse

BACKGROUND

The adoption of minimally invasive techniques to perform mitral valve repair surgery is increasing. This is enhanced by the compelling evidence of satisfactory short-term results and lower major morbidity. We analyzed mid-term follow-up results of our experience, and further compared two techniques: isolated leaflet resection and neochord implantation for posterior leaflet prolapse.

METHODS

Data for all consecutive endoscopic mitral valve repairs via video-assisted right anterior mini-thoracotomy were analyzed between December 2012 and September 2021. The early and mid-term follow-up results were ascertained. The main outcome was the incidence of mortality and the recurrence of significant mitral regurgitation during follow-up which were summarized by the Kaplan-Meier estimator and compared between treatment arms using the stratified log-rank test. Secondary outcomes were the early-postoperative results including 30-days mortality and the occurrence of major complications.

RESULTS

A total of 309 patients were included. Along with ring annuloplasty, 136 (44.4%) patients received posterior leaflet resection (122 isolated) whereas 97 (31.1%) underwent posterior leaflet chords implantation (88 isolated). Forty-nine patients had annuloplasty alone. In-hospital mortality was 1.0%. Mean follow-up was 28.8 ± 22.0 months (maximum 8.3 years). Kaplan-Meier survival rate at 5 years was 97.3 ± 1.0%, mitral regurgitation ([Formula: see text]3+) or valve reoperation free-survival at 5 years was estimated as 94.5 ± 2.3%. Subgroup time-to-event analysis for the indexed outcomes showed no statistical significance between the techniques.

CONCLUSIONS

Endoscopic mitral valve repair is safe and associated with excellent short- and mid-term outcomes. No differences were found between leaflet resection and gore-tex chords implantation for posterior leaflet prolapse.

Case Report: Post-gastrectomy reactive hyperinsulinemic hypoglicaemia: glucose trends before and after canagliflozin treatment

The pathogenesis of post-gastrectomy reactive hyperinsulinaemic hypoglycaemia is not yet fully clarified. Recent studies suggest an up-regulation of the intestinal glucose transporter SGLT-1 aimed to prevent carbohydrate malabsorption. The overexpression of SGLT-1 could therefore represents one of the mechanisms underlying the wide glycemic excursions found in patients after gastrectomy, but studies investigating the use of SGLT-1/SGLT-2 inhibitors in patients with post-gastrectomy reactive hyperinsulinemic hypoglycaemia are very scant in the literature. We report the case of a 37-year-old non diabetic man who frequently presented symptoms of hypoglycaemia in the postprandial period. In 2012, he underwent Roux en-Y gastric bypass (RYGB) and after two years, he started to experience typical symptoms of reactive hyperinsulinaemic hypoglycaemia. We suggested healthy modifications of dietary habits and periodic follow-up visits with a dietitian. After three months, the patient still presented symptoms of reactive hypoglycaemia; we provided him with Flash Glucose Monitoring (FGM) to assess trend of glucose levels in interstitial fluid during the day and we decided to introduce canagliflozin 300 mg/day before the main meal. Hypoglycaemic events previously referred by the patient and clearly recorded by FGM completely disappeared taking canagliflozin. We found a reduction of time spent in hypoglycaemia, an improvement of glycemic variability and an increase of time in target range. It was also noted a reduction of time spent in hyperglicemia with consequent improvement of average glucose values and of glucose main indicator. This is the first report with FGM supporting a role of canagliflozin in the management of post-gastrectomy reactive hyperinsulinaemic hypoglycaemia. Our preliminary results are very limited but in line with those of the literature and showed for the first time a reduction of hypoglycaemic events and an improvement of glycemic variability through a flash glucose monitoring system. Further studies are mandatory to confirm this therapeutic opportunity.

Toxoplasma gondii Investigation of Home-Reared Pigs through Real-Time PCR and Digital Droplet PCR: A Very Low Prevalence

Toxoplasma gondii is a widespread protozoon that can infect both animals and humans. The main route of human infection is the consumption of the raw or undercooked meat of several animal species, including pigs. Although T. gondii represents a public health concern, control during slaughter is not mandatory, leading to a lack of information on the impact on human contagion as well as poor data availability in domestic animals intended for human consumption. We studied the presence of T. gondii in home-reared pigs, an unconventional type of farming subjected to stringent breeding conditions dictated by Italian regulation. Thus, the diaphragms, livers and masseter muscles from 480 pigs in Napoli Province (Italy) were analyzed using real-time PCR and digital droplet PCR. The results showed four matrices that tested positive for T. gondii with very low protozoan loads (0.62%), belonging to three different animals. The low density of the animals (the maximum was four animals per farm) and the biosafety farming features decisively contributed to the bioexclusion of this pathogen. Comparing these results to intensive and extensive farm data, lower exposure to the parasite was revealed, suggesting that this farming method might mitigate the risk of human exposure through meat consumption.

KRAS-Dependency in Pancreatic Ductal Adenocarcinoma: Mechanisms of Escaping in Resistance to KRAS Inhibitors and Perspectives of Therapy

Pancreatic ductal adenocarcinoma (PDAC) is still one of the deadliest cancers in oncology because of its increasing incidence and poor survival rate. More than 90% of PDAC patients are KRAS mutated (KRASmu), with KRASG12D and KRASG12V being the most common mutations. Despite this critical role, its characteristics have made direct targeting of the RAS protein extremely difficult. KRAS regulates development, cell growth, epigenetically dysregulated differentiation, and survival in PDAC through activation of key downstream pathways, such as MAPK-ERK and PI3K-AKT-mammalian target of rapamycin (mTOR) signaling, in a KRAS-dependent manner. KRASmu induces the occurrence of acinar-to-ductal metaplasia (ADM) and pancreatic intraepithelial neoplasia (PanIN) and leads to an immunosuppressive tumor microenvironment (TME). In this context, the oncogenic mutation of KRAS induces an epigenetic program that leads to the initiation of PDAC. Several studies have identified multiple direct and indirect inhibitors of KRAS signaling. Therefore, KRAS dependency is so essential in KRASmu PDAC that cancer cells have secured several compensatory escape mechanisms to counteract the efficacy of KRAS inhibitors, such as activation of MEK/ERK signaling or YAP1 upregulation. This review will provide insights into KRAS dependency in PDAC and analyze recent data on inhibitors of KRAS signaling, focusing on how cancer cells establish compensatory escape mechanisms.

CXCR1/2 dual-inhibitor ladarixin reduces tumour burden and promotes immunotherapy response in pancreatic cancer

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignancy with few therapeutic options available. Despite immunotherapy has revolutionised cancer treatment, the results obtained in PDAC are still disappointing. Emerging evidence suggests that chemokines/CXCRs-axis plays a pivotal role in immune tumour microenvironment modulation, which may influence immunotherapy responsiveness. Here, we evaluated the effectiveness of CXCR1/2 inhibitor ladarixin, alone or in combination with anti-PD-1, against immunosuppression in PDAC.

METHODS

A set of preclinical models was obtained by engrafting mouse PDAC-derived cells into syngeneic immune-competent mice, as well as by orthotopically transplanting patient-derived PDAC tumour into human immune-system-reconstituted (HIR) mice (HuCD34-NSG-mice). Tumour-bearing mice were randomly assigned to receive vehicles, ladarixin, anti-PD-1 or drugs combination.

RESULTS

CXCR1/2 inhibition by ladarixin reverted in vitro tumour-mediated M2 macrophages polarisation and migration. Ladarixin as single agent reduced tumour burden in cancer-derived graft (CDG) models with high-immunogenic potential and increased the efficacy of ICI in non-immunogenic CDG-resistant models. In a HIR mouse model bearing the immunogenic subtype of human PDAC, ladarixin showed high efficacy increasing the antitumor effect of anti-PD-1.

CONCLUSION

Ladarixin in combination with anti-PD-1 might represent an extremely effective approach for the treatment of immunotherapy refractory PDAC, allowing pro-tumoral to immune-permissive microenvironment conversion.

Serum Inflammatory Profile in Hereditary Transthyretin Amyloidosis: Mechanisms and Possible Therapeutic Implications

Hereditary transthyretin (ATTRv) amyloidosis is a severe, progressive, and heterogeneous multisystemic condition due to mutations in the TTR gene. Although multiple aspects of its molecular pathophysiological mechanisms have been elucidated over the years, it is possible to hypothesize different pathogenetic pathways. Indeed, we extensively investigated the serum levels of several molecules involved in the immune response, in a cohort of ATTRv patients and healthy controls (HCs). Sixteen ATTRv patients and twenty-five HCs were included in the study. IFN-alpha levels were higher in ATTRv patients than in HCs, as well as IFN-gamma levels. By contrast, IL-7 levels were lower in ATTRv patients than in HCs. No significant difference between groups was found regarding IL-1Ra, IL-6, IL-2, IL-4, and IL-33 levels. Correlation analysis did not reveal any significant correlation between IFN-α, IFN-γ, IL-7, and demographic and clinical data. Larger and longitudinal studies using ultrasensitive methods to perform a full cytokine profiling are needed to better elucidate the role of inflammation in ATTRv pathogenesis and to test the reliability of these molecules as possible biomarkers in monitoring patients' progression.

Unweaving the mitotic spindle: A focus on Aurora kinase inhibitors in lung cancer

Lung cancer is one of the most aggressive malignancies, classified into two major histological subtypes: non-small cell lung cancer (NSCLC), that accounts for about 85% of new diagnosis, and small cell lung cancer (SCLC), the other 15%. In the case of NSCLC, comprehensive genome sequencing has allowed the identification of an increasing number of actionable targets, which have become the cornerstone of treatment in the advanced setting. On the other hand, the concept of oncogene-addiction is lacking in SCLC, and the only innovation of the last 30 years has been the introduction of immune checkpoint inhibitors in extensive stage disease. Dysregulation of cell cycle is a fundamental step in carcinogenesis, and Aurora kinases (AURKs) are a family of serine/threonine kinases that play a crucial role in the correct advance through the steps of the cycle. Hyperexpression of Aurora kinases is a common protumorigenic pathway in many cancer types, including NSCLC and SCLC; in addition, different mechanisms of resistance to anticancer drugs rely on AURK expression. Hence, small molecule inhibitors of AURKs have been developed in recent years and tested in several malignancies, with different results. The aim of this review is to analyze the current evidences of AURK inhibition in lung cancer, starting from preclinical rationale to finish with clinical trials available up to now.

Immunogenic Cell Death: An Emerging Target in Gastrointestinal Cancers

Immunogenic cell death (ICD) is a regulated form of cell death that induces the activation of both innate and adaptive immune responses through the release of damage-associated molecular patterns (DAMPs) and their subsequent recognition by pattern-recognition receptors (PRRs), generating specific CD8+ T lymphocytes. Thus, ICD inducers (such as certain chemotherapeutic agents, targeted therapies, radiation, and oncolytic viruses) could become a potential cancer treatment by providing antitumour immunity and cancer vaccination. Moreover, their combination with immunotherapy, especially with immune checkpoint inhibitors, could overcome the immunosuppressive tumour microenvironment that characterises certain cancers, including gastrointestinal cancers. This review will provide insights into the role of ICD induction in colorectal, gastric, pancreatic, and hepatocellular carcinomas. Specifically, we will discuss the main mechanisms involved in ICD, their potential application in gastrointestinal cancer treatment, and the latest clinical trial updates.

Generation and in vivo validation of an IL-12 fusion protein based on a novel anti-human FAP monoclonal antibody

BACKGROUND

In this study, we describe the generation of a fully human monoclonal antibody (named '7NP2') targeting human fibroblast activation protein (FAP), an antigen expressed in the microenvironment of different types of solid neoplasms.

METHODS

7NP2 was isolated from a synthetic antibody phage display library and was improved by one round of mutagenesis-based affinity maturation. The tumor recognition properties of the antibody were validated by immunofluorescence procedures performed on cancer biopsies from human patients. A fusion protein consisting of the 7NP2 antibody linked to interleukin (IL)-12 was generated and the anticancer activity of the murine surrogate product (named mIL12-7NP2) was evaluated in mouse models. Furthermore, the safety of the fully human product (named IL12-7NP2) was evaluated in Cynomolgus monkeys.

RESULTS

Biodistribution analysis in tumor-bearing mice confirmed the ability of the product to selectively localize to solid tumors while sparing healthy organs. Encouraged by these results, therapy studies were conducted in vivo, showing a potent antitumor activity in immunocompetent and immunodeficient mouse models of cancer, both as single agent and in combination with immune checkpoint inhibitors. The fully human product was tolerated when administered to non-human primates.

CONCLUSIONS

The results obtained in this work provided a rationale for future clinical translation activities using IL12-7NP2.

Targeting hypoxia-inducible factor pathways in sporadic and Von Hippel-Lindau syndrome-related kidney cancers

Hereditary and sporadic renal cell carcinomas (RCCs) are often associated with Von Hippel-Lindau (VHL)-gene inactivation. Patients with VHL disease have an increased risk of RCC, leading to bilateral nephrectomy and dialysis. In patients with advanced RCC, no standard second-lines are available after progression to immune checkpoint inhibitors (ICIs), and new agents are required to manage progression. HIFs have emerged as a promising target for metastatic RCC patients who have progressed to ICI-based combinations, as well as for those with RCC and VHL syndrome where the goal is to delay surgery and/or and preserve kidney function and avoid dialysis. This review describes the available evidence supporting the use of the small-molecule HIF-2 alpha inhibitor, belzutifan (MK-6482), as well as other new anti-HIF molecules that have demonstrated significant efficacy in VHL disease-related RCCs as well as for sporadic RCC that has progressed after the use of ICI-based combinations.

The role of CXCR1/2 dual inhibitor ladarixin on tumor burden and immunotherapy response in pancreatic cancer

e16304

Background: Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignancies for which few effective pharmacological treatments are currently available. Immunotherapy has revolutionized the treatment of several solid tumors, yet the results obtained in PDAC have been disappointing. Although PDAC is generally considered an immune “cold” cancer, different PDAC subtypes have diverse immune tissue microenvironment (TME) components, including tumor-associated macrophages (TAMs), that might differentially influence immunotherapy responsiveness and patient survival. TAM population is plastic, switching rapidly from a pro- to an anti-tumoral behaviour, based on specific cytokines in TME. A role for the chemokines/CXCR axis in inducing M1 polarization has been proposed in several tumors, and, consequently, the potential advantage of combining CXCR inhibitors with immune check-point inhibitors. Here, we evaluated the effectiveness of the CXCR1/2 inhibitor ladarixin, alone or in combination with anti-PD-1, on immune tolerance against PDAC and on tumor growth. Methods: A set of preclinical models were obtained by engrafting mouse PDAC-derived cell lines into the pancreas of recipient syngeneic immune-competent mice, as well as by orthotopically transplanting patient derived PDAC tumor into human immune system reconstituted (HIR) mice (Hu-NSG-CD34+). Tumor bearing mice were randomly assigned to receive vehicles, ladarixin, and anti-PD-1 alone or in combination with ladarixin, to evaluate the effect of treatment on tumor growth and mice survival. This work is supported by AIRC and Italian Ministry of Health grants. Results: CXCR1/2 inhibition by ladarixin reverted in vitro tumor-mediated M2 polarization and migration of Bone Marrow-Derived Macrophages. Ladarixin as a single agent significantly reduced tumor burden in cancer derived graft (CDG) models with high-immunogenic potential and significantly increased the efficacy of ICI in non-immunogenic CDG models that did not respond to anti-PD-1 treatment. In a HIR mouse model bearing the immunogenic subtype of human PDAC, ladarixin showed high efficacy as a single agent and the ability to increase the antitumor effects of anti-PD-1 with a statistically significant reduction of tumor volume compared to control and to single treatments (ctr vs lad, p = 0.0077; ctr vs comb, p = 0.0098; lad vs comb: 0.002; anti-PD-1 vs comb, p = 0.036). Moreover, ladarixin both as monotherapy and in combination setting increased survival (median survival: ctr 49.5 vs lad 74.5 days, p = 0.044; ctr 49.5 vs comb 150 days, p = 0.0108; anti-PD-1 57 vs comb 150 days, p = 0.046; lad 74.5 vs comb 150 days, p = 0.047). Conclusions: Ladarixin in combination with anti-PD-1 might represent an effective approach for the treatment of PDAC, converting a protumoral into an immunopermissive microenvironment in PDAC subtypes usually refractory to immunotherapy.

Understanding Tricky Cellular and Molecular Interactions in Pancreatic Tumor Microenvironment: New Food for Thought

Pancreatic ductal adenocarcinoma (PDAC) represents 90% of all pancreatic cancer cases and shows a high mortality rate among all solid tumors. PDAC is often associated with poor prognosis, due to the late diagnosis that leads to metastasis development, and limited efficacy of available treatments. The tumor microenvironment (TME) represents a reliable source of novel targets for therapy, and even if many of the biological interactions among stromal, immune, and cancer cells that populate the TME have been studied, much more needs to be clarified. The great limitation in the efficacy of current standard chemoterapy is due to both the dense fibrotic inaccessible TME barrier surrounding cancer cells and the immunological evolution from a tumor-suppressor to an immunosuppressive environment. Nevertheless, combinatorial therapies may prove more effective at overcoming resistance mechanisms and achieving tumor cell killing. To achieve this result, a deeper understanding of the pathological mechanisms driving tumor progression and immune escape is required in order to design rationale-based therapeutic strategies. This review aims to summarize the present knowledge about cellular interactions in the TME, with much attention on immunosuppressive functioning and a specific focus on extracellular matrix (ECM) contribution.

SARS-CoV-2 Serological and Biomolecular Analyses among Companion Animals in Campania Region (2020–2021)

The first reports of SARS-CoV-2 among domestic and wild animals, together with the rapid emergence of new variants, have created serious concerns regarding a possible spillback from animal hosts, which could accelerate the evolution of new viral strains. The present study aimed to investigate the prevalence and the transmission of SARS-CoV-2 among both owned and stray pets. A total of 182 dogs and 313 cats were tested for SARS-CoV-2. Specimens collected among owned and stray pets were subjected to RT-PCR and serological examinations. No viral RNA was detected, while anti-N antibodies were observed in six animals (1.3%), one dog (0.8%) and five cats (1.7%). Animals’ background revealed that owned cats, living with owners with COVID-19, showed significantly different prevalence compared to stray ones (p = 0.0067), while no difference was found among dogs. Among the seropositive pets, three owned cats also showed moderate neutralizing antibody titers. Pets and other species are susceptible to SARS-CoV-2 infection because of the spike affinity towards their ACE2 cellular receptor. Nevertheless, the risk of retransmission remains unclear since pet-to-human transmission has never been described. Due to the virus’ high mutation rate, new reservoirs cannot be excluded; thus, it is reasonable to test pets, mostly if living in households affected by COVID-19.

The Renaissance of KRAS Targeting in Advanced Non-Small-Cell Lung Cancer: New Opportunities Following Old Failures

Non-small cell lung cancer (NSCLC) represents the perfect paradigm of ‘precision medicine’ due to its complex intratumoral heterogeneity. It is truly characterized by a range of molecular alterations that can deeply influence the natural history of this disease. Several molecular alterations have been found over time, paving the road to biomarker-driven therapy and radically changing the prognosis of ‘oncogene addicted’ NSCLC patients. Kirsten rat sarcoma (KRAS) mutations are present in up to 30% of NSCLC (especially in adenocarcinoma histotype) and have been identified decades ago. Since its discovery, its molecular characteristics and its marked affinity to a specific substrate have led to define KRAS as an undruggable alteration. Despite that, many attempts have been made to develop drugs capable of targeting KRAS signaling but, until a few years ago, these efforts have been unsuccessful. Comprehensive genomic profiling and wide-spectrum analysis of genetic alterations have only recently allowed to identify different types of KRAS mutations. This tricky step has finally opened new frontiers in the treatment approach of KRAS-mutant patients and might hopefully increase their prognosis and quality of life. In this review, we aim to highlight the most interesting aspects of (epi)genetic KRAS features, hoping to light the way to the state of art of targeting KRAS in NSCLC.

Pancreatic Cancer Patient-Derived Organoid Platforms: A Clinical Tool to Study Cell- and Non-Cell-Autonomous Mechanisms of Treatment Response

For many years, cell lines and animal models have been essential to improve our understanding of the basis of cell metabolism, signaling, and genetics. They also provided an essential boost to cancer drug discovery. Nevertheless, these model systems failed to reproduce the tumor heterogeneity and the complex biological interactions between cancer cells and human hosts, making a high priority search for alternative methods that are able to export results from model systems to humans, which has become a major bottleneck in the drug development. The emergent human in vitro 3D cell culture technologies have attracted widespread attention because they seem to have the potential to overcome these limitations. Organoids are unique 3D culture models with the ability to self-organize in contained structures. Their versatility has offered an exceptional window of opportunity to approach human cancers. Pancreatic cancers (PCs) patient-derived-organoids (PDOs) preserve histological, genomic, and molecular features of neoplasms they originate from and therefore retain their heterogeneity. Patient-derived organoids can be established with a high success rate from minimal tissue core specimens acquired with endoscopic-ultrasound-guided techniques and assembled into platforms, representing tens to hundreds of cancers each conserving specific features, expanding the types of patient samples that can be propagated and analyzed in the laboratory. Because of their nature, PDO platforms are multipurpose systems that can be easily adapted in co-culture settings to perform a wide spectrum of studies, ranging from drug discovery to immune response evaluation to tumor-stroma interaction. This possibility to increase the complexity of organoids creating a hybrid culture with non-epithelial cells increases the interest in organoid-based platforms giving a pragmatic way to deeply study biological interactions in vitro. In this view, implementing organoid models in co-clinical trials to compare drug responses may represent the next step toward even more personalized medicine. In the present review, we discuss how PDO platforms are shaping modern-day oncology aiding to unravel the most complex aspects of PC.

Iatrogenic Acute Aortic Dissection in the Era of Minimally Invasive Cardiac Surgery - Experience of a Center and Review of Literature

Introduction

Iatrogenic acute aortic dissection (IAAD) type A is a rare but potentially fatal complication of cardiac surgery.

Methods

The purpose of this article is to review the literature since the first reports of IAAD in 1978, examining its clinical characteristics and describing operative details and surgical outcomes. Moreover, we reviewed the recent literature to identify current trends and risk factors for IAAD in minimally invasive cardiac surgery procedures, often related to femoral artery cannulation for retrograde perfusion.

Results

We found that IAAD ranges from 0.04 to 0.29% of cardiac patients in overall trials and ranged from 0.12 to 0.16% between 1978-1990, before the minimally invasive surgical era. And we concluded that since the first cases to the recent reports, the incidence of IAAD has not significantly changed. As minimally invasive procedures are on the rise, some authors think that the incidence of IAAD could increase in the future; we think that using all the precaution - such a strict monitoring of perfusion pressure throughout the intervention, avoiding extremely high jet pressures using vasodilators, repositioning of arterial cannula, or splitting perfusion in both femoral arteries -, this complication can be extremely reduced. Finally, we describe a very singular case occurring during mitral valve replacement followed by spontaneous dissection of left anterior descending artery one month later.

Conclusion

The present article adds to the literature a more detailed clinical picture of this entity, including patients' characteristics, the mechanism, timing, and localization of the tear, and mortality details.

Intratumoral injection of TLR9 agonist promotes an immunopermissive microenvironment transition and causes cooperative antitumor activity in combination with anti-PD1 in pancreatic cancer

Background

Complex tumor and immune microenvironment render pancreatic ductal adenocarcinoma (PDAC) resistant to immune checkpoint inhibitors (ICIs). Therefore, a strategy to convert the immune hostile into an immunopermissive tumor is required. Recent studies showed that intratumoral injection of Toll-like receptor 9 agonist IMO-2125 primes the adaptive immune response. Phase I and II trials with intratumoral IMO-2125 demonstrated its safety and antitumoral activity.

Methods

We generated an array of preclinical models by orthotopically engrafting PDAC-derived cell lines in syngeneic mice and categorized them as high, low and no immunogenic potential, based on the ability of tumor to evoke T lymphocyte or NK cell response. To test the antitumor efficacy of IMO-2125 on locally treated and distant sites, we engrafted cancer cells on both flanks of syngeneic mice and treated them with intratumoral IMO-2125 or vehicle, alone or in combination with anti-PD1 ICI. Tumor tissues and systemic immunity were analyzed by transcriptomic, cytofluorimetric and immunohistochemistry analysis.

Results

We demonstrated that intratumoral IMO-2125 as single agent triggers immune system response to kill local and distant tumors in a selected high immunogenic subtype affecting tumor growth and mice survival. Remarkably, intratumoral IMO-2125 in combination with systemic anti-PD1 causes a potent antitumor effect on primary injected and distant sites also in pancreatic cancer models with low immunogenic potential, preceded by a transition toward an immunopermissive microenvironment, with increase in tumor-infiltrating dendritic and T cells in tumor and lymph nodes.

Conclusion

We demonstrated a potent antitumor activity of IMO-2125 and anti-PD1 combination in immunotherapy-resistant PDAC models through the modulation of immune microenvironment, providing the rationale to translate this strategy into a clinical setting.

New insights into vitamin D regulation: is there a role for alkaline phosphatase?

PURPOSE

The diagnosis of vitamin D deficiency is based on the determination of total plasma 25-hydroxyvitamin D (25-OHD) concentrations, but the regulation of vitamin D 25-hydroxylation is not a major consideration and very little information is available on this activity. To check what factors could interfere with the activity of vitamin D-25-hydroxylase and thus alter the 25-OHD concentrations, we looked for potential correlations between 25-OHD and results of liver function tests in healthy adults.

METHODS

This single-centre study was retrospective and consisted of evaluating the correlations between 25-OHD and the activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyl transpeptidase (GGT), alkaline phosphatase (ALP), and bone alkaline phosphatase (BALP) in 349 healthy subjects aged from 18 to 65 years. In particular, in Group 1 (n = 119), we looked for correlations between 25OHD and all liver function tests and in Group 2 (n = 230) the correlation between 25OHD and BALP.

RESULTS

In Group 1, we found no correlation between 25OHD and AST (r =  - 0.03; p = 0.8), ALT (r =  - 0.02; p = 0.91), GGT (r =  - 0.08; p = 0.68), direct bilirubin (r =  - 0.02; p = 0.89), indirect bilirubin (r =  - 0.24; p = 0.21), and total bilirubin (r =  - 0.24; p = 0.21) but one between 25OHD and ALP (r =  - 0.2; p = 0.007); in Group 2, we found a significant negative correlation between 25-OHD and BALP (r =  - 0.2; p = 0.0008).

CONCLUSIONS

The correlations that we found suggest that ALP and BALP might be involved in the regulation of vitamin D-25-hydroxylase activity, but further studies are mandatory to confirm our assumptions.

Translational Research in the Era of Precision Medicine: Where We Are and Where We Will Go

The advent of Precision Medicine has globally revolutionized the approach of translational research suggesting a patient-centric vision with therapeutic choices driven by the identification of specific predictive biomarkers of response to avoid ineffective therapies and reduce adverse effects. The spread of "multi-omics" analysis and the use of sensors, together with the ability to acquire clinical, behavioral, and environmental information on a large scale, will allow the digitization of the state of health or disease of each person, and the creation of a global health management system capable of generating real-time knowledge and new opportunities for prevention and therapy in the individual person (high-definition medicine). Real world data-based translational applications represent a promising alternative to the traditional evidence-based medicine (EBM) approaches that are based on the use of randomized clinical trials to test the selected hypothesis. Multi-modality data integration is necessary for example in precision oncology where an Avatar interface allows several simulations in order to define the best therapeutic scheme for each cancer patient.

Transition from unclassified Ktedonobacterales to Actinobacteria during amorphous silica precipitation in a quartzite cave environment

The orthoquartzite Imawarì Yeuta cave hosts exceptional silica speleothems and represents a unique model system to study the geomicrobiology associated to silica amorphization processes under aphotic and stable physical-chemical conditions. In this study, three consecutive evolution steps in the formation of a peculiar blackish coralloid silica speleothem were studied using a combination of morphological, mineralogical/elemental and microbiological analyses. Microbial communities were characterized using Illumina sequencing of 16S rRNA gene and clone library analysis of carbon monoxide dehydrogenase (coxL) and hydrogenase (hypD) genes involved in atmospheric trace gases utilization. The first stage of the silica amorphization process was dominated by members of a still undescribed microbial lineage belonging to the Ktedonobacterales order, probably involved in the pioneering colonization of quartzitic environments. Actinobacteria of the Pseudonocardiaceae and Acidothermaceae families dominated the intermediate amorphous silica speleothem and the final coralloid silica speleothem, respectively. The atmospheric trace gases oxidizers mostly corresponded to the main bacterial taxa present in each speleothem stage. These results provide novel understanding of the microbial community structure accompanying amorphization processes and of coxL and hypD gene expression possibly driving atmospheric trace gases metabolism in dark oligotrophic caves.

Endoscopic ultrasound-guided therapies for pancreatic solid tumors: An overview

The close proximity of the endoscopic ultrasound (EUS) probe to the pancreas, coupled with the ease with which a needle can be inserted into a pancreatic lesion, have contributed to the development of EUS-guided therapies for both adenocarcinoma and neuroendocrine pancreatic neoplasms. EUS-guided fine needle injection of different types of drugs, implantation of fiducial markers to facilitate stereotactic body radiation therapy or of radioactive seeds to perform brachytherapy, and the use of different thermal and nonthermal ablation devices and techniques have all been tested in preliminary human studies. This manuscript will present the available evidence accumulated thus far in the field of EUS-guided oncological treatment of pancreatic solid tumors, along with a look into possible future applications.

PTEN Loss as a Predictor of Tumor Heterogeneity and Poor Prognosis in Patients With EGFR-mutant Advanced Non-small-cell Lung Cancer Receiving Tyrosine Kinase Inhibitors

BACKGROUND

Rapid disease progression of patients with advanced epidermal growth factor receptor (EGFR)-mutant non-small-cell lung cancer (NSCLC) has been recently associated with tumor heterogeneity, which may be mirrored by coexisting concomitant alterations. The aim of this analysis was to investigate the correlation between loss of function of PTEN and the efficacy of tyrosine kinase inhibitors in this population.

MATERIALS AND METHODS

Archival tumor blocks from patients with EGFR-mutant NSCLC who were administered upfront tyrosine kinase inhibitors were retrospectively collected. The status of 4 genes (PTEN, TP53, c-MET, IGFR) was evaluated by immunohistochemistry, and it was correlated with overall response rate, overall survival (OS), and progression-free survival (PFS).

RESULTS

Fifty-one patients were included. In multivariate analysis, PTEN loss (hazard ratio [HR], 3.46; 95% confidence interval [CI], 1.56-7.66; P = .002), IGFR overexpression (HR, 2.22; 95% CI, 1.03-4.77; P = .04), liver metastases (HR, 3.55; 95% CI, 1.46-8.65; P = .005), and Eastern Cooperative Oncology Group performance status (ECOG PS) ≥ 1 (HR, 2.57; 95% CI, 1.04-6.34; P = .04) were significantly associated with shorter PFS. Patients with PTEN loss had a median PFS of 6 months (2-year PFS, 11.6%), whereas patients without PTEN loss had a median PFS of 18 months (2-year PFS, 43.6%) (log-rank P < .005). In the multivariate analysis, PTEN loss (HR, 5.92; 95% CI, 2.37-14.81; P < .005), liver metastases (HR, 2.63; 95% CI, 1.06-6.51; P = .037), and ECOG PS ≥ 1 (HR, 2.80; 95% CI, 1.15-6.81; P = .024) were significantly associated with shorter OS. Patients with PTEN loss had a median OS of 6 months (2-year OS, 12.2%), whereas in patients without PTEN loss, OS was not reached (2-year OS, 63.9%) (log-rank P < .0005).

CONCLUSIONS

A low-cost and reproducible immunohistochemistry assay for PTEN loss analysis represents a potential tool for identifying tumor heterogeneity in patients with advanced EGFR-mutant NSCLC.

Minimally invasive tricuspid valve surgery without caval occlusion: Short and midterm results

OBJECTIVE

The use of minimally invasive or transcatheter interventions rather than standard full sternotomy operations to treat tricuspid valve (TV) disease is increasing. The debate however is still open regarding venous drainage management during cardiopulmonary bypass (CPB) and wheatear or not superior and inferior vena cava should be occluded during the opening of the right atrium to avoid air entrance in the venous line. The aim of the present study is to report operative outcomes and midterm follow-up results of minimally invasive TV surgery performed without caval occlusion.

METHODS

A retrospective outcome evaluation from institutional records was performed with prospective data entry. Considered were consecutive patients who underwent right mini-thoracotomy TV surgery isolated or combined with mitral valve surgery during the period from June 2013 to February 2020. A telephone and echocardiographic follow-up was performed.

RESULTS

During the study period, 68 consecutive patients underwent minimally invasive TV surgery without occlusion of cava veins. The mean age was 69 ± 14 years and 48 (70%) were female. All operations were performed safely without air-lock during CPB. A perioperative cerebral stroke occurred in one patient. The survival at a 5- and 8-year follow-up was 100% and 79%, respectively. No severe tricuspid regurgitation was evident at echocardiographic follow-up.

CONCLUSION

Our results show that performing tricuspid surgery without caval occlusion is safe. The air was captured by the active vacuum drainage system without causing damage. Midterm follow-up data confirm that a minimally invasive approach does not alter the quality of surgery.

Systemic profile of immune factors in an elderly Italian population affected by chronic strongyloidiasis

Background

Strongyloidiasis caused by Strongyloides stercoralis is a soil-transmitted helminthiasis affecting an estimated 370 million people and considered one of the most neglected tropical diseases. Although mostly distributed in tropical and subtropical areas, autochthonous infections have also been documented in north-eastern Italy, even though the transmission presumably stopped decades ago. Because of its peculiar auto-infective cycle, strongyloidiasis can persist lifelong, but the pathophysiological mechanisms associated with the maintenance of such a chronic infection are yet to be fully deciphered.

Methods

Serum levels of 23 immune factors were retrospectively assessed in a subgroup of participants in a randomised clinical trial for the treatment of strongyloidiasis (Strong Treat). Here we included Italian subjects born between 1931 and 1964 and diagnosed with strongyloidiasis between 2013 and 2017 (Ss⁺, n = 32). Serum samples obtained before (BT) and 6 months (6M AT) after ivermectin treatment, as well as from age- and gender-matched uninfected controls (CTRL, n = 34) were analysed.

Results

The assessed immune factors showed a general reduced concertation in Ss⁺ patients and a lack of association with eosinophilia. In our cohort, we did not observe the classical shift towards a type 2 immune response, since Th1 and Th2 cytokines were mostly unaltered. Instead, we observed chemokines as particularly affected by the presence of the parasite, since IL-8, CCL3, CCL4 and CCL5 were significantly reduced in concentration in Ss⁺ subjects compared to CTRL, suggesting that immune cell recruitment to the infection site might be dampened in these patients. This observation was further sustained by a significant increase of CCL4, CCL5 and CCL11 concentrations 6M AT. A significant raised systemic concentration of three growth factors, bFGF, PDGF-BB and IL-7 (haematopoietic growth factor) was also observed post-treatment, indicating a potential involvement in restoring tissue integrity and homeostasis following parasite elimination.

Conclusions

These preliminary data suggest that, in order to survive for such a long period, S. stercoralis might suppress host responses that could otherwise result in its ejection. Our results offer novel insights in the potential mechanisms of disease tolerance that might take place during this chronic infection, including a potential T-cell hypo-responsiveness and a role for chemokines.

Gut microbiome, big data and machine learning to promote precision medicine for cancer

The gut microbiome has been implicated in cancer in several ways, as specific microbial signatures are known to promote cancer development and influence safety, tolerability and efficacy of therapies. The 'omics' technologies used for microbiome analysis continuously evolve and, although much of the research is still at an early stage, large-scale datasets of ever increasing size and complexity are being produced. However, there are varying levels of difficulty in realizing the full potential of these new tools, which limit our ability to critically analyse much of the available data. In this Perspective, we provide a brief overview on the role of gut microbiome in cancer and focus on the need, role and limitations of a machine learning-driven approach to analyse large amounts of complex health-care information in the era of big data. We also discuss the potential application of microbiome-based big data aimed at promoting precision medicine in cancer.

Small Molecule Inhibitors of Microenvironmental Wnt/β-Catenin Signaling Enhance the Chemosensitivity of Acute Myeloid Leukemia

Wnt/β-catenin signaling has been reported in Acute Myeloid leukemia, but little is known about its significance as a prognostic biomarker and drug target. In this study, we first evaluated the correlation between expression levels of Wnt molecules and clinical outcome. Then, we studied-in vitro and in vivo-the anti-leukemic value of combinatorial treatment between Wnt inhibitors and classic anti-leukemia drugs. Higher levels of β-catenin, Ser675-phospho-β-catenin and GSK-3α (total and Ser 9) were found in AML cells from intermediate or poor risk patients; nevertheless, patients presenting high activity of Wnt/β-catenin displayed shorter progression-free survival (PFS) according to univariate analysis. In vitro, many pharmacological inhibitors of Wnt signalling, i.e., LRP6 (Niclosamide), GSK-3 (LiCl, AR-A014418), and TCF/LEF (PNU-74654) but not Porcupine (IWP-2), significantly reduced proliferation and improved the drug sensitivity of AML cells cultured alone or in the presence of bone marrow stromal cells. In vivo, PNU-74654, Niclosamide and LiCl administration significantly reduced the bone marrow leukemic burden acting synergistically with Ara-C, thus improving mouse survival. Overall, our study demonstrates the antileukemic role of Wnt/β-catenin inhibition that may represent a potential new therapeutics strategy in AML.

Topologization of β-antimonene on Bi2Se3 via proximity effects

Topological surface states usually emerge at the boundary between a topological and a conventional insulator. Their precise physical character and spatial localization depend on the complex interplay between the chemical, structural and electronic properties of the two insulators in contact. Using a lattice-matched heterointerface of single and double bilayers of β-antimonene and bismuth selenide, we perform a comprehensive experimental and theoretical study of the chiral surface states by means of microscopy and spectroscopic measurements complemented by first-principles calculations. We demonstrate that, although β-antimonene is a trivial insulator in its free-standing form, it inherits the unique symmetry-protected spin texture from the substrate via a proximity effect that induces outward migration of the topological state. This "topologization" of β-antimonene is found to be driven by the hybridization of the bands from either side of the interface.

Pathologic angiogenesis in the bone marrow of humanized sickle cell mice is reversed by blood transfusion

Sickle cell disease (SCD) is a monogenic red blood cell (RBC) disorder with high morbidity and mortality. Here, we report, for the first time, the impact of SCD on the bone marrow (BM) vascular niche, which is critical for hematopoiesis. In SCD mice, we find a disorganized and structurally abnormal BM vascular network of increased numbers of highly tortuous arterioles occupying the majority of the BM cavity, as well as fragmented sinusoidal vessels filled with aggregates of erythroid and myeloid cells. By in vivo imaging, sickle and control RBCs have significantly slow intravascular flow speeds in sickle cell BM but not in control BM. In sickle cell BM, we find increased reactive oxygen species production in expanded erythroblast populations and elevated levels of HIF-1α. The SCD BM exudate exhibits increased levels of proangiogenic growth factors and soluble vascular cell adhesion molecule-1. Transplantation of SCD mouse BM cells into wild-type mice recapitulates the SCD vascular phenotype. Our data provide a model of SCD BM, in which slow RBC flow and vaso-occlusions further diminish local oxygen availability in the physiologic hypoxic BM cavity. These events trigger a milieu that is conducive to aberrant vessel growth. The distorted neovascular network is completely reversed by a 6-week blood transfusion regimen targeting hemoglobin S to <30%, highlighting the plasticity of the vascular niche. A better insight into the BM microenvironments in SCD might provide opportunities to optimize approaches toward efficient and long-term hematopoietic engraftment in the context of curative therapies.

Blood serum amyloid A as potential biomarker of pembrolizumab efficacy for patients affected by advanced non-small cell lung cancer (NSCLC) overexpressing PD-L1: Early results of the FoRECATT Study

9598

Background: Identifying the patients who may benefit the most from immune checkpoints inhibitors remains a great challenge for clinicians. The tumor-derived Serum Amyloid A (SAA) inhibits the immune-response in melanoma patients. Here we present the early results of FoRECATT study investigating on blood SAA as biomarker of response to upfront pembrolizumab in patients with advanced non-small-cell lung cancer (NSCLC). Methods: In this prospective study, patients with PD-L1 ≥ 50% receiving upfront pembrolizumab (P cohort) and with PD-L1 0-49% treated with chemotherapy (CT cohort), were evaluated for blood SAA and radiological response at baseline and every 9 weeks. Primary endpoint was response rate (RR) according to Response Evaluation Criteria in Solid Tumors 1.1; secondary endpoints were progression-free (PFS) and overall survival (OS). The most accurate SAA cut-off to predict response was established with ROC-analysis in the P cohort. Results: In the P Cohort (n = 42), the overall RR was 38%. After a median follow-up of 18.5 months (mo), baseline SAA ≤ the ROC-derived cut-off (29.9 mg/L; n = 14/42, 33%) was significantly associated with higher RR (53.6 versus 7.1%; OR 15, 95%CI 1.72-130.7, P= 0.009), longer PFS (17.4 versus 2.1 mo; P< 0.0001) and OS (not reached versus 7.2 mo; P< 0.0001) compared with SAA > 29.9 mg/L. In multivariate analysis, low SAA positively affects PFS ( P= 0.001) and OS ( P= 0.048) irrespective of ECOG PS, number of metastatic sites and pleural effusion. SAA monitoring (n = 40) was also significantly associated with survival endpoints: median PFS 17.4 versus 2.1 mo and median OS not reached versus 7.2 mo when SAA remained low (n = 14) and high (n = 12), respectively. In the CT Cohort (n = 30), RR was not significantly affected by SAA level, while low SAA at baseline (n = 17) was associated with better PFS (HR = 0.42, 95%CI 0.16-1.10, P= 0.02) and OS (HR = 0.16, 95% CI 0.04-0.55, P= 0.0004). Conclusions: Low SAA predicts a higher likelihood of response to upfront pembrolizumab only and good survival outcomes irrespective of treatment in advanced NSCLC patients. Therefore, a simple blood test might be useful to identify patients likely to derive better outcomes from immunotherapy. A further study (FoRECATT-2) is ongoing to confirm the results in a larger validation cohort and to assess the potential effect of SAA on immune response in vitro assays.

Organoid-Transplant Model Systems to Study the Effects of Obesity on the Pancreatic Carcinogenesis in vivo

Pancreatic ductal adenocarcinoma (PDAC) is the third leading cause of cancer-related mortality among adults in developed countries. The discovery of the most common genetic alterations as well as the development of organoid models of pancreatic cancer have provided insight into the fundamental pathways driving tumor progression from a normal cell to non-invasive precursor lesion and finally to widely metastatic disease, offering new opportunities for identifying the key driver of cancer evolution. Obesity is one of the most serious public health challenges of the 21st century. Several epidemiological studies have shown the positive association between obesity and cancer-related morbidity/mortality, as well as poorer prognosis and treatment outcome. Despite strong evidence indicates a link between obesity and cancer incidence, the molecular basis of the initiating events remains largely elusive. This is mainly due to the lack of an accurate and reliable model of pancreatic carcinogenesis that mimics human obesity-associated PDAC, making data interpretation difficult and often confusing. Here we propose a feasible and manageable organoid-based preclinical tool to study the effects of obesity on pancreatic carcinogenesis. Therefore, we tracked the effects of obesity on the natural evolution of PDAC in a genetically defined transplantable model of the syngeneic murine pancreatic preneoplastic lesion (mP) and tumor (mT) derived-organoids that recapitulates the progression of human disease from early preinvasive lesions to metastatic disease. Our results suggest that organoid-derived transplant in obese mice represents a suitable system to study early steps of pancreatic carcinogenesis and supports the hypothesis that inflammation induced by obesity stimulates tumor progression and metastatization during pancreatic carcinogenesis.

Aortic valve endocarditis complicated by proximal false aneurysm

Background

Aortic valve endocarditis remains a life-threatening condition, especially in cases of periannular complications. Aorto-ventricular discontinuity associated with proximal false aneurysm represents a severe picture caused by extensive tissue disruption and is usually associated with prosthetic valve infection. Complex surgical repair is required in these cases and continues to be associated with high mortality and morbidity rates.

Methods

We retrieved information for 32 patients undergoing operation for infective aortic valve/prosthetic valve endocarditis complicated by pseudoaneurysm arising from aorto-ventricular discontinuity. Patients were relatively young, mostly male and most of them had a prior cardiac operation. Aortic root replacement with valve graft conduit was performed in all cases; it was associated with other procedures in seven patients: CABG (n=2), MV surgery (n=3), MV surgery + CABG (n=1) and pulmonary valve replacement (n=1). We reported and analysed patient outcomes at early and mid-term follow-up.

Results

Pre-discharge mortality was 22% (n=7). The postoperative course was complicated in 24 (75%) cases. Eighteen patients (56%) sustained low cardiac output resulting in multiple organ failure syndrome and death in five cases. One patient (3%) experienced a major neurologic deficit with a permanent cerebral stroke. Acute kidney injury complicated the course in 12 cases (37%), continuous renal replacement therapy was necessary in four patients (12%). Overall survival and freedom from endocarditis and reoperation at 5-year was 59% and 89%, respectively.

Conclusions

Patients with complicated aortic valve endocarditis presented generally in a poor preoperative state. Surgical treatment poses a non-negligible risk of postoperative mortality and morbidity but provides an acceptable survival rate and a satisfactory recovery at mid-term.

Immunosuppression by monocytic myeloid-derived suppressor cells in patients with pancreatic ductal carcinoma is orchestrated by STAT3

Background

Pancreatic ductal adenocarcinoma (PDAC) is a highly devastating disease with an overall 5-year survival rate of less than 8%. New evidence indicates that PDAC cells release pro-inflammatory metabolites that induce a marked alteration of normal hematopoiesis, favoring the expansion and accumulation of myeloid-derived suppressor cells (MDSCs). We report here that PDAC patients show increased levels of both circulating and tumor-infiltrating MDSC-like cells.

Methods

The frequency of MDSC subsets in the peripheral blood was determined by flow cytometry in three independent cohorts of PDAC patients (total analyzed patients, n = 117). Frequency of circulating MDSCs was correlated with overall survival of PDAC patients. We also analyzed the frequency of tumor-infiltrating MDSC and the immune landscape in fresh biopsies. Purified myeloid cell subsets were tested in vitro for their T-cell suppressive capacity.

Results

Correlation with clinical data revealed that MDSC frequency was significantly associated with a shorter patients’ overall survival and metastatic disease. However, the immunosuppressive activity of purified MDSCs was detectable only in some patients and mainly limited to the monocytic subset. A transcriptome analysis of the immunosuppressive M-MDSCs highlighted a distinct gene signature in which STAT3 was crucial for monocyte re-programming. Suppressive M-MDSCs can be characterized as circulating STAT3/arginase1-expressing CD14⁺ cells.

Conclusion

MDSC analysis aids in defining the immune landscape of PDAC patients for a more appropriate diagnosis, stratification and treatment.

PTEN in Lung Cancer: Dealing with the Problem, Building on New Knowledge and Turning the Game Around

Lung cancer is the most common malignancy and cause of cancer deaths worldwide, owing to the dismal prognosis for most affected patients. Phosphatase and tensin homolog deleted in chromosome 10 (PTEN) acts as a powerful tumor suppressor gene and even partial reduction of its levels increases cancer susceptibility. While the most validated anti-oncogenic duty of PTEN is the negative regulation of the PI3K/mTOR/Akt oncogenic signaling pathway, further tumor suppressor functions, such as chromosomal integrity and DNA repair have been reported. PTEN protein loss is a frequent event in lung cancer, but genetic alterations are not equally detected. It has been demonstrated that its expression is regulated at multiple genetic and epigenetic levels and deeper delineation of these mechanisms might provide fertile ground for upgrading lung cancer therapeutics. Today, PTEN expression is usually determined by immunohistochemistry and low protein levels have been associated with decreased survival in lung cancer. Moreover, available data involve PTEN mutations and loss of activity with resistance to targeted treatments and immunotherapy. This review discusses the current knowledge about PTEN status in lung cancer, highlighting the prevalence of its alterations in the disease, the regulatory mechanisms and the implications of PTEN on available treatment options.