Nectin-4: a new prognostic biomarker for efficient therapeutic targeting of primary and metastatic triple-negative breast cancer

Background

Triple-negative breast cancers (TNBCs) are associated with a poor prognosis. In contrast to other molecular subtypes, they have no identified specific target and chemotherapy remains the only available systemic treatment. The adhesion molecule nectin-4 represents a new potential therapeutic target in different cancer models. Here, we have tested the prognostic value of nectin-4 expression and assessed the therapeutic efficiency of an anti-nectin 4 antibody drug conjugate (ADC) on localised and metastatic TNBC in vitro and in vivo.

Materials and methods

We analysed nectin-4/PVRL4 mRNA expression in 5673 invasive breast cancers and searched for correlations with clinicopathological features including metastasis-free survival (MFS). Immunohistochemistry was carried out in 61 TNBCs and in samples of primary TNBC Patient-Derived Xenografts (PDXs). An anti-nectin-4 antibody eligible for ADC was produced and tested in vitro and in vivo in localised and metastatic TNBC PDXs.

Results

High nectin-4/PVRL4 mRNA expression was associated with poor-prognosis features including the TN and basal subtypes. High PVRL4 mRNA expression showed independent negative prognostic value for MFS in multivariate analysis in TNBCs. Nectin-4 protein expression was not detected in adult healthy tissues including mammary tissue. Membranous protein expression was found in 62% of TNBCs, with strong correlation with mRNA expression. We developed an ADC (N41mab-vcMMAE) comprising a human anti-nectin-4 monoclonal antibody conjugated to monomethyl auristatin-E (MMAE). In vitro, this ADC bound to nectin-4 with high affinity and specificity and induced its internalisation as well as dose-dependent cytotoxicity on nectin-4-expressing breast cancer cell lines. In vivo, this ADC induced rapid, complete and durable responses on nectin-4-positive xenograft TNBC samples including primary tumours, metastatic lesions, and local relapses; efficiency was dependent on both the dose and the nectin-4 tumour expression level.

Conclusion

Nectin-4 is both a new promising prognostic biomarker and specific therapeutic target for ADC in the very limited armamentarium against TNBC.

Morphological evidences following pegylated filler treatment in human skin

In this study, microscopic, histochemical and ultrastructural observations in human skin are presented, 8 months after an injection of a novel PEGylated filler. Morphological features demonstrated an excellent integration of the filler with the connective tissue components and an effective interpenetration with the ground substance. The filler appears uniformly distributed inside the hypodermis. No segregation or encapsulation of cells and other structures was observed nor evidence of immunological adverse reaction. Furthermore, observed ultrastructural modifications of fibroblasts supports a stimulatory effect of molecular components production of the extracellular matrix, contributing to the cutaneous connective tissue renewal.

Epstein-Barr virus lytic infection promotes activation of Toll-like receptor 8 innate immune response in systemic sclerosis monocytes

Background

Monocytes/macrophages are activated in several autoimmune diseases, including systemic sclerosis (scleroderma; SSc), with increased expression of interferon (IFN)-regulatory genes and inflammatory cytokines, suggesting dysregulation of the innate immune response in autoimmunity. In this study, we investigated whether the lytic form of Epstein-Barr virus (EBV) infection (infectious EBV) is present in scleroderma monocytes and contributes to their activation in SSc.

Methods

Monocytes were isolated from peripheral blood mononuclear cells (PBMCs) depleted of the CD19+ cell fraction, using CD14/CD16 negative-depletion. Circulating monocytes from SSc and healthy donors (HDs) were infected with EBV. Gene expression of innate immune mediators were evaluated in EBV-infected monocytes from SSc and HDs. Involvement of Toll-like receptor (TLR)8 in viral-mediated TLR8 response was investigated by comparing the TLR8 expression induced by infectious EBV to the expression stimulated by CL075/TLR8/agonist-ligand in the presence of TLR8 inhibitor in THP-1 cells.

Results

Infectious EBV strongly induced TLR8 expression in infected SSc and HD monocytes in vitro. Markers of activated monocytes, such as IFN-regulated genes and chemokines, were upregulated in SSc- and HD-EBV-infected monocytes. Inhibiting TLR8 expression reduced virally induced TLR8 in THP-1 infected cells, demonstrating that innate immune activation by infectious EBV is partially dependent on TLR8. Viral mRNA and proteins were detected in freshly isolated SSc monocytes. Microarray analysis substantiated the evidence of an increased IFN signature and altered level of TLR8 expression in SSc monocytes carrying infectious EBV compared to HD monocytes.

Conclusion

This study provides the first evidence of infectious EBV in monocytes from patients with SSc and links EBV to the activation of TLR8 and IFN innate immune response in freshly isolated SSc monocytes. This study provides the first evidence of EBV replication activating the TLR8 molecular pathway in primary monocytes. Immunogenicity of infectious EBV suggests a novel mechanism mediating monocyte inflammation in SSc, by which EBV triggers the innate immune response in infected cells.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-017-1237-9) contains supplementary material, which is available to authorized users.

Long-term survival of patients with critical limb ischemia treated with iloprost: response rate and predictive criteria. A retrospective analysis of 102 patients

OBJECTIVE

Critical limb ischemia (CLI) patients have poor long-term prognosis. We showed that iloprost improves outcomes (major amputation and survival) up a 5-year follow-up, but it is not known if in this length of time the survival curves, of clinical responders and non-responders, differ.

PATIENTS AND METHODS

A retrospective study enrolling 102 consecutive patients between 2004-2008, with clinical and instrumental (ultrasound, angiography, transcutaneous tensiometry of oxygen TcpO2 and carbon dioxide TcpCO2 in the affected and contralateral limbs) diagnosis of critical ischemia. All patients received the best medical therapy. Iloprost was administered (0.5-2 ng/kg/min 6 hours/day for 2-4 weeks) in all patients initially considered unsuitable for revascularization, repeating it regularly in time every six-twelve months in the case of positive response. The minimum expected follow-up was 4 years.

RESULTS

71.5% of patients were treated with iloprost and the responder rate was 71.2%. Most of the patients were regularly retreated with repeated cycles. Initial median supine TcpCO2 in symptomatic limb was higher in untreated patients than those treated (58 vs. 49 mmHg; p < 0.05) and in non-responders compared to responders (60 vs. 49 mmHg; p < 0.05). TcpCO2 directly and significantly correlated with the highest risk of mortality and seems to represent a new accurate prognostic criterion of unfavourable short and long-term response to prostanoid. In iloprost group, major amputations were significantly reduced. Revascularization was significantly higher in non-responders (57.1% vs. 11.5%; p < 0.05). There was a significantly higher prevalence of subsequent myocardial infarction in the non-iloprost group (27.6% vs. 9.6%; p < 0.05). The survival rate of non-responders was higher than untreated up until the second year (76.2% vs. 62%; p < 0.05). At 4 years we found higher survival in patients treated with iloprost (64.3% vs. 41% in untreated; p < 0.05) and in responders (75% vs. 38.1% in non-responders; p < 0.05).

CONCLUSIONS

Our results confirm the favourable role of iloprost on the long-term outcome in patients with CLI. In particular, the maximum benefit is obtained in responder patients treated with multiple cycles of infusion.

Fresh Insights into Disease Etiology and the Role of Microbial Pathogens

Pathogens have been implicated in the initiation and/or promotion of systemic sclerosis (scleroderma, SSc); however, no evidence was found to substantiate the direct contribution to this disease in past years. Recently, significant advances have been made in understanding the role of the innate immune system in SSc pathogenesis, supporting the idea that pathogens might interact with host innate immune-regulatory responses in SSc. In light of these findings, we review the studies that identified the presence of pathogens in SSc, along with studies on pathogens implicated in driving the innate immune dysregulation in SSc. The goal of this review is to illustrate how these pathogens, specifically viruses, may play important role both as triggers of the innate immune system, and critical players in the development of SSc disease.

Efficacy, safety and feasibility of intravenous iloprost in the domiciliary treatment of patients with ischemic disease of the lower limbs

OBJECTIVE

Intravenous iloprost is an important option in the treatment of ischemic disease of the lower limbs; however, the administration of therapy is frequently compromised because of the need for long cycles of infusion in a hospital setting. The aim of the study is to evaluate the efficacy, safety, feasibility, and the economic impact of infusion therapy in the outpatient setting.

PATIENTS AND METHODS

Twenty-four consecutive patients were treated with iloprost at their homes where they were administered a slow rate of infusion for 24 hours a day, during 9.9 ± 2.3 days, with a portable syringe pump (Infonde®).

RESULTS

The clinical condition of patients evaluated with the modified SVS/ISCVS scale significantly improved after treatment (+1.29 ± 1.04 points vs. baseline, p<0.001). The drug was well tolerated; neither significant adverse events associated with medication nor problems related to venous access were recorded at home. Ninety-six percent of patients successfully completed the entire treatment cycle, and the evaluation questionnaire showed a high acceptance of the therapy. From the perspective of the hospital authority, lower direct medical costs were estimated for the domiciliary infusion process compared with the inpatient infusion setting.

CONCLUSIONS

Treatment with iloprost in the outpatient setting is effective, safe, feasible, and more acceptable to patients than infusion at the hospital. In addition, it has a favorable economic and organizational impact on the medical ward.

Long-term clinical outcomes in critical limb ischemia--A retrospective study of 181 patients

OBJECTIVE

Critical limb ischemia (CLI) is the most severe manifestation of the peripheral arterial disease. To date, several prognostic factors have been identified but the data of long-term follow-up in real life setting are scarce. The aim of our study is to describe a large group of CLI patients and identify possible prognostic factors, in a long-term follow-up.

PATIENTS AND METHODS

Case-control, retrospective study. 181 consecutive CLI patients with a minimum follow-up of 5 years were included in the study.

RESULTS

Overall mortality was 15%, 24%, and 43% at 1, 2, and 5 years, respectively. Among known risk factors, only arterial hypertension was significantly correlated with survival rate; no differences were found between diabetics and non-diabetics. Patients treated with intravenous iloprost (46%), compared to untreated patients, showed a better (p < 0.0001) long-term outcome in terms of major amputation (6% vs. 21%), subsequent vascular surgery (4% vs. 32%) and survival rates (69% vs. 47%), at 5-year follow-up. Major amputations were significantly correlated with lower median forefoot transcutaneous values of O2 (0/3 mmHg, p < 0.001) and higher median values of CO2 (83/53 mmHg, p < 0.0001) in supine/dependent position, respectively.

CONCLUSIONS

Our results confirm the poor prognosis of CLI patients in a very long-term follow-up and the severe metabolic damage caused by ischemia. A favourable role of iloprost was observed, in agreement with previous evidence in the literature.

The activation of KSHV lytic cycle blocks autophagy in PEL cells

This study confirms that autophagy is activated concomitantly with KSHV lytic cycle induction, and that autophagy inhibition by BECN1 knockdown reduces viral lytic gene expression. In addition, we extend previous observations and show that autophagy is blocked at late steps, during viral replication. This is indicated by the lack of colocalization of autophagosomes and lysosomes and by the LC3-II level that does not increase in the presence of bafilomycin A₁ in primary effusion lymphoma (PEL) cells induced to enter the lytic cycle, either by TPA/sodium butyrate (BC3 and BCBL1) or by doxycycline (TRExBCBL1-Rta). The autophagic block correlates with the downregulation of RAB7, whose silencing with specific siRNA results in an autophagic block in the same cells. Finally, by electron microscopy analysis, we observed viral particles inside autophagic vesicles in the cytoplasm of PEL cells undergoing viral replication, suggesting that they may be involved in viral transport.

PKC theta and p38 MAPK activate the EBV lytic cycle through autophagy induction

PKC activation by combining TPA with sodium butyrate (T/B) represents the most effective and widely used strategy to induce the Epstein-Barr virus (EBV) lytic cycle. The results obtained in this study show that novel PKCθ is involved in such process and that it acts through the activation of p38 MAPK and autophagy induction. Autophagy, a mechanism of cellular defense in stressful conditions, is manipulated by EBV to enhance viral replication. Besides promoting the EBV lytic cycle, the activation of p38 and autophagy resulted in a pro-survival effect, as indicated by p38 or ATG5 knocking down experiments. However, this pro-survival role was counteracted by a pro-death activity of PKCθ, due to the dephosphorylation of AKT. In conclusion, this study reports, for the first time, that T/B activates a PKCθ-p38 MAPK axis in EBV infected B cells, that promotes the viral lytic cycle and cell survival and dephosphorylates AKT, balancing cell life and cell death.

Determination of reference values for optical properties of liquid phantoms based on Intralipid and India ink

A multi-center study has been set up to accurately characterize the optical properties of diffusive liquid phantoms based on Intralipid and India ink at near-infrared (NIR) wavelengths. Nine research laboratories from six countries adopting different measurement techniques, instrumental set-ups, and data analysis methods determined at their best the optical properties and relative uncertainties of diffusive dilutions prepared with common samples of the two compounds. By exploiting a suitable statistical model, comprehensive reference values at three NIR wavelengths for the intrinsic absorption coefficient of India ink and the intrinsic reduced scattering coefficient of Intralipid-20% were determined with an uncertainty of about 2% or better, depending on the wavelength considered, and 1%, respectively. Even if in this study we focused on particular batches of India ink and Intralipid, the reference values determined here represent a solid and useful starting point for preparing diffusive liquid phantoms with accurately defined optical properties. Furthermore, due to the ready availability, low cost, long-term stability and batch-to-batch reproducibility of these compounds, they provide a unique fundamental tool for the calibration and performance assessment of diffuse optical spectroscopy instrumentation intended to be used in laboratory or clinical environment. Finally, the collaborative work presented here demonstrates that the accuracy level attained in this work for optical properties of diffusive phantoms is reliable.

Is retroperitoneoscopic renal ablative surgery easier and safer using a new hemostatic device compared with clips and monopolar coagulation? A comparative study

AIM

The aim of study was to retrospectively analyze our series of total and partial retroperiotoneoscopic nephrectomies performed in the last 5 years.

METHODS

Twenty-two procedures were performed, 20 patients underwent nephrectomy and 2 patients underwent partial nephrectomy. The 20 patients who underwent nephrectomy were divided in 2 groups: group 1 (G1) patients-1-10, for whom we performed the procedure using monopolar coagulation, and group 2 (G2) patients 11-20 for whom we used a new hemostatic device to perform dissection and hemostasis. The results were analyzed using χ2 test. The results of partial nephrectomies were analyzed separately.

RESULTS

No conversion were reported. We analyzed 6 parameters to compare the results: operative time (OT), estimated blood loss (EBL), need for transfusion (NT), complications, time to oral intake (TOI), hospital stay (HS). OT in G1 was in median 85 minutes, in G2 65 minutes (P=0.004); EBL was 15 mL for G1 and 5 mL for G2 (P=0.000.), NT was not necessary in both, in G1 we had 2 complications and 1 complication in G2; TOI was day 1 for both groups; median HS was 3 days for both. As for heminephrectomy, OT was 120 and 140 min, EBL 30 mL in both, NT not necessary, TOI was 1 day and HS 4 and 5 days respectively.

CONCLUSION

Our study shows that the use of a new hemostatic devices reduce significantly OT and EBL in children underwent renal ablative surgery for benign pathologies compared with the use of monopolar coagulation.

Insulin-like growth factor binding proteins 4 and 7 released by senescent cells promote premature senescence in mesenchymal stem cells

Cellular senescence is the permanent arrest of cell cycle, physiologically related to aging and aging-associated diseases. Senescence is also recognized as a mechanism for limiting the regenerative potential of stem cells and to protect cells from cancer development. The senescence program is realized through autocrine/paracrine pathways based on the activation of a peculiar senescence-associated secretory phenotype (SASP). We show here that conditioned media (CM) of senescent mesenchymal stem cells (MSCs) contain a set of secreted factors that are able to induce a full senescence response in young cells. To delineate a hallmark of stem cells SASP, we have characterized the factors secreted by senescent MSC identifying insulin-like growth factor binding proteins 4 and 7 (IGFBP4 and IGFBP7) as key components needed for triggering senescence in young MSC. The pro-senescent effects of IGFBP4 and IGFBP7 are reversed by single or simultaneous immunodepletion of either proteins from senescent-CM. The blocking of IGFBP4/7 also reduces apoptosis and promotes cell growth, suggesting that they may have a pleiotropic effect on MSC biology. Furthermore, the simultaneous addition of rIGFBP4/7 increased senescence and induced apoptosis in young MSC. Collectively, these results suggest the occurrence of novel-secreted factors regulating MSC cellular senescence of potential importance for regenerative medicine and cancer therapy.

Kaposi sarcoma associated herpesvirus (KSHV) induces AKT hyperphosphorylation, bortezomib-resistance and GLUT-1 plasma membrane exposure in THP-1 monocytic cell line

Background

Phosphatidylinositol-3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) signaling pathway regulates multiple cellular processes such as cell proliferation, evasion from apoptosis, migration, glucose metabolism, protein synthesis and proper differentiation in immune cells. Kaposi sarcoma-associated herpesvirus (KSHV), an oncogenic virus associated with several human malignancies, expresses a variety of latent and lytic proteins able to activate PI3K/AKT pathway, promoting the growth of infected cells and a successful viral infection.

Results

We found that KSHV latent infection of THP-1 cells, a human monocytic cell line derived from an acute monocytic leukemia patient, resulted in an increase of AKT phoshorylation, not susceptible to bortezomib-induced dephosphorylation, compared to the mock-infected THP-1. Accordingly, THP-1-infected cells displayed increased resistance to the bortezomib cytotoxic effect in comparison to the uninfected cells, which was counteracted by pre-treatment with AKT-specific inhibitors. Finally, AKT hyperactivation by KSHV infection correlated with plasma membrane exposure of glucose transporter GLUT1, particularly evident during bortezomib treatment. GLUT1 membrane trafficking is a characteristic of malignant cells and underlies a change of glucose metabolism that ensures the survival to highly proliferating cells and render these cells highly dependent on glycolysis. GLUT1 membrane trafficking in KSHV-infected THP-1 cells indeed led to increased sensitivity to cell death induced by the glycolysis inhibitor 2-Deoxy-D-glucose (2DG), further potentiated by its combination with bortezomib.

Conclusions

KSHV confers to the THP-1 infected cells an oncogenic potential by altering the phosphorylation, expression and localization of key molecules that control cell survival and metabolism such as AKT and GLUT1. Such modifications in one hand lead to resistance to cell death induced by some chemotherapeutic drugs such as bortezomib, but on the other hand, offer an Achilles heel, rendering the infected cells more sensitive to other treatments such as AKT or glycolysis inhibitors. These therapeutic strategies can be exploited in the anticancer therapy of KSHV-associated malignancies.

Epstein-Barr virus infection induces aberrant TLR activation pathway and fibroblast-myofibroblast conversion in scleroderma

Scleroderma (SSc) is a complex and heterogeneous connective tissue disease mainly characterized by autoimmunity, vascular damage, and fibrosis that mostly involve the skin and lungs. Epstein–Barr virus (EBV) is a lymphotropic γ-herpesvirus that has co-evolved with human species, infecting >95% of the adult population worldwide, and has been a leading candidate in triggering several autoimmune diseases. Here we show that EBV establishes infection in the majority of fibroblasts and endothelial cells in the skin of SSc patients, characterized by the expression of the EBV noncoding small RNAs (EBERs) and the increased expression of immediate-early lytic and latency mRNAs and proteins. We report that EBV is able to persistently infect human SSc fibroblasts in vitro, inducing an aberrant innate immune response in infected cells. EBV–Toll-like receptor (TLR) aberrant activation induces the expression of selected IFN-regulatory factors (IRFs), IFN-stimulated genes (ISGs), transforming growth factor-β1 (TGFβ1), and several markers of fibroblast activation, such as smooth muscle actin and Endothelin-1, and all of these genes play a key role in determining the profibrotic phenotype in SSc fibroblasts. These findings imply that EBV infection occurring in mesenchymal, endothelial, and immune cells of SSc patients may underlie the main pathological features of SSc including autoimmunity, vasculopathy, and fibrosis, and provide a unified disease mechanism represented by EBV reactivation.

Sonographic evaluation of the lower uterine segment thickness in women with a single previous Cesarean section

AIM

The aim of this paper was to evaluate the lower uterine segment (LUS) thickness through transvaginal sonography in late preterm and full term pregnancies with a single previous Cesarean section, to correlate the obtained LUS measurements with intraoperative observations, and to identify a predictive cut-off value in order to select the best candidates for a vaginal birth after Cesarean delivery (VBAC).

METHODS

Two hundred and fourteen women with a single previous Cesarean section who had an ultrasound measurement of the LUS thickness (stratified in S1, S2 and S3) in pregnancy were enrolled. The outcome of interest was the visual finding of a thin uterine scar at the time of the iterative Cesarean section. Linear regression was used to correlate the LUS thickness with gestational age (GA). A ROC curve has been used to determine the detection rate (DR) and the risk of each actual value of LUS thickness versus a thin uterine scar (outcome of interest).

RESULTS

The LUS thickness was correlated with the gestational age (R2=0.034, P-value =0.005). The DR as estimated by ROC curves to detect a translucent lower uterine segment (S3) was 94.1% at a false positive rate (FPR) of 20%. The correspondent cut-off value was 1.8 mm. Finally a likelihood ratio (LR) of observing S3 was estimated. At the quoted cut-off of 1.8 mm the LR was 3. As demonstrated, for a segment of 1 mm the LR was instead about 13.

CONCLUSION

The obtained values lead us to the conclusion that a thickness less than 1.8 mm can be reasonably considered a valid cut-off value to identify patients with a higher risk of thin uterine scar.

Vaginal delivery rate in post-term pregnancies with one versus more than one dinoprostone gel administrations: an observational study

AIM

The study aims to calculate the probability of a successful vaginal delivery in post-term low-risk women by using a set of predictors (maternal, fetal, and ultrasonographic) according to the number of dinoprostone gel applications.

METHODS

This was an observational study of a cohort of 174 low-risk post-term singleton pregnancies. Parity, cervical status and length, and amniotic fluid volume (AFI) were evaluated immediately before prostaglandin gel induction at the Department of Obstetrics and Gynecology, University of Bologna, Bologna, Italy between January 2010 and October 2011.

RESULTS

A consistent difference in vaginal delivery rates was observed for women who had one gel administration (Group 1) versus those who received either two or three gel administrations (Group 2): 77.5% at 24 hours and 97.4% at 48 hours vs. 27% at 24 hours and 54% at 48 hours (P <0.001 for both the comparisons) respectively. The predictors of a vaginal delivery were cervix dilatation and short cervix for Group 1, lower AFI for Group 2, and parity for both groups.

CONCLUSION

Women who require more than one gel administration have a lower rate of vaginal delivery at 24 and 48 hours. Maternal, fetal, and ultrasonographic parameters can predict a successful vaginal delivery.