TRAIL and targeting cancer cells: between promises and obstacles

Targeting cancer cells is one of the challenges of current treatment strategies. TRAIL represents a promising therapeutic approach and over the past decades there was an increased interest in targeting TRAIL signaling to treat cancer. Indeed, TRAIL can specifically target cancer cells and exhibits very low cytotoxicity towards normal cells. However, rapidly accumulating experimental evidence has started to shed light on multiple factors which induce resistance against TRAIL in cancer cells. This resistance consists of various mechanisms including downregulation of death receptors and caspase-8 and overexpression of decoy receptors as well as antiapoptotic factors such as members of Bcl-2 family. Even if several studies focused on elucidating those resistance mechanisms, there still remain gray areas that need to be fully elucidated. Thus, therapeutic approaches could consist of targeting both resistance signaling pathways and TRAIL signaling to enhance TRAIL therapy efficiency.

HCV viral load at baseline and at week 4 of telaprevir/boceprevir based triple therapies are associated with virological outcome in HIV/hepatitis C co-infected patients

BACKGROUND

As first generation HCV-specific protease inhibitors, boceprevir (BOC) or telaprevir (TVR) can achieve 60% to 70% sustained virological response (SVR) for HCV infected patients with genotype 1 infections, they could remain temporary a therapeutic option in patients living in resources limited countries with limited access to the new anti-HCV direct acting antiviral (DAA) drugs, such as sofosbuvir.

OBJECTIVES AND STUDY DESIGN

Here we evaluated in a routine practice setting, the treatment responses, tolerance and factors associated with SVR of a triple therapy with BOC or TVR, combined with pegylated interferon and ribavirin (PegIFN/RBV) in HIV/HCV co-infected patients, included in a large cohort of HIV/HCV coinfected patients (ANRS CO13-HEPAVIH).

RESULTS

Among the 89 HIV/HCV coinfected patients treated, 65% of whom were previous non-responders to PegIFN/RBV therapy, 65%, 55% and 41% had at baseline genotype 1a, a high baseline HCV-RNA (≥800,000 IU/ml) and a cirrhosis, respectively. The SVR12 rate was 63% overall, 53% for BOC-based regimen and 66% for TVR-based regimen. In multivariate analysis, two factors were significantly associated with HCV SVR: HCV viral load <800,000 IU/mL at treatment initiation versus ≥800,000 IU/mL (OR 4.403, 95% CI 1.29-15.04; p=0.018) and virological response at W4 (HCV-RNA undetectable after 4 weeks of triple therapy) (OR 3.35, 95% CI 1.07-10.48; p=0.038).

CONCLUSIONS

Overall SVR12 was 63% and our results suggest that HIV/HCV coinfected patients with low HCV viral load (<800,000 IU/mL) and undetectable HCV-RNA after 4 weeks of triple therapy with TVR or BOC-based regimen have a higher probability of treatment success.

Mast-cell interleukin-1β, neutrophil interleukin-17 and epidermal antimicrobial proteins in the neutrophilic urticarial dermatosis in Schnitzler's syndrome

BACKGROUND

Schnitzler's syndrome (SchS) is an autoinflammatory disease characterized by a chronic urticarial rash, a monoclonal component and signs of systemic inflammation. Interleukin (IL)-1β is pivotal in the pathophysiology.

OBJECTIVES

Here we investigated the cellular source of proinflammatory mediators in the skin of patients with SchS.

METHODS

Skin biopsies of lesional and nonlesional skin from eight patients with SchS and healthy controls, and patients with cryopyrin-associated periodic syndrome (CAPS), delayed-pressure urticaria (DPU) and cold-contact urticaria (CCU) were studied. We studied in vivoIL-1β, IL-17 and antimicrobial protein (AMP) expression in resident skin cells and infiltrating cells. In addition we investigated the in vitro effect of IL-1β, IL-17 and polyinosinic-polycytidylic acid (poly:IC) stimulation on cultured epidermal keratinocytes.

RESULTS

Remarkably, we found IL-1β-positive dermal mast cells in both lesional and nonlesional skin of patients with SchS, but not in healthy control skin and CCU, and fewer in CAPS. IL-17-positive neutrophils were observed only in lesional SchS and DPU skin. In lesional SchS epidermis, mRNA and protein expression levels of AMPs were strongly increased compared with nonlesional skin and that of healthy controls. When exposed to IL-1β, poly:IC or IL-17, patient and control primary human keratinocytes produced AMPs in similar amounts.

CONCLUSIONS

Dermal mast cells of patients with SchS produce IL-1β. This presumably leads to activation of keratinocytes and neutrophil influx, and further amplification of inflammation by IL-17 (from neutrophils and mast cells) and epidermal AMP production leading to chronic histamine-independent neutrophilic urticarial dermatosis.

National Healthcare Delivery Systems Influence Lung Transplant Outcomes for Cystic Fibrosis

Successful lung transplantation (LTx) depends on multiple components of healthcare delivery and performance. Therefore, we conducted an international registry analysis to compare post-LTx outcomes for cystic fibrosis (CF) patients using the UNOS registry in the United States and the National Health Service (NHS) Transplant Registry in the United Kingdom. Patients with CF who underwent lung or heart-lung transplantation in the United States or United Kingdom between January 1, 2000 and December 31, 2011 were included. The primary outcome was all-cause mortality. Kaplan-Meier analysis and Cox proportional hazards regression evaluated the effect of healthcare system and insurance on mortality after LTx. 2,307 US LTx recipients and 451 individuals in the United Kingdom were included. 894 (38.8%) US LTx recipients had publically funded Medicare/Medicaid insurance. US private insurance and UK patients had improved median predicted survival compared with US Medicare/Medicaid recipients (p < 0.001). In multivariable Cox regression, US Medicare/Medicaid insurance was associated with worse survival after LTx (US private: HR0.78,0.68-0.90,p = 0.001 and UK: HR0.63,0.41-0.97, p = 0.03). This study in CF patients is the largest comparison of LTx in two unique health systems. Both the United States and United Kingdom have similar early survival outcomes, suggesting important dissemination of best practices internationally. However, the performance of US public insurance is significantly worse and may put patients at risk.

Bloodstream infection in paediatric cancer centres--leukaemia and relapsed malignancies are independent risk factors

In a prospective multicentre study of bloodstream infection (BSI) from November 01, 2007 to July 31, 2010, seven paediatric cancer centres (PCC) from Germany and one from Switzerland included 770 paediatric cancer patients (58% males; median age 8.3 years, interquartile range (IQR) 3.8-14.8 years) comprising 153,193 individual days of surveillance (in- and outpatient days during intensive treatment). Broviac catheters were used in 63% of all patients and Ports in 20%. One hundred forty-two patients (18%; 95% CI 16 to 21%) experienced at least one BSI (179 BSIs in total; bacteraemia 70%, bacterial sepsis 27%, candidaemia 2%). In 57%, the BSI occurred in inpatients, in 79% after conventional chemotherapy. Only 56 % of the patients showed neutropenia at BSI onset. Eventually, patients with acute lymphoblastic leukaemia (ALL) or acute myeloblastic leukaemia (AML), relapsed malignancy and patients with a Broviac faced an increased risk of BSI in the multivariate analysis. Relapsed malignancy (16%) was an independent risk factor for all BSI and for Gram-positive BSI.

CONCLUSION

This study confirms relapsed malignancy as an independent risk factor for BSIs in paediatric cancer patients. On a unit level, data on BSIs in this high-risk population derived from prospective surveillance are not only mandatory to decide on empiric antimicrobial treatment but also beneficial in planning and evaluating preventive bundles.

WHAT IS KNOWN

• Paediatric cancer patients face an increased risk of nosocomial bloodstream infections (BSIs). • In most cases, these BSIs are associated with the use of a long-term central venous catheter (Broviac, Port), severe and prolonged immunosuppression (e.g. neutropenia) and other chemotherapy-induced alterations of host defence mechanisms (e.g. mucositis). What is New: • This study is the first multicentre study confirming relapsed malignancy as an independent risk factor for BSIs in paediatric cancer patients. • It describes the epidemiology of nosocomial BSI in paediatric cancer patients mainly outside the stem cell transplantation setting during conventional intensive therapy and argues for prospective surveillance programmes to target and evaluate preventive bundle interventions.

Adrenal enzyme impairment in neonates and adolescents treated with ritonavir and protease inhibitors for HIV exposure or infection

BACKGROUND

Human deficiency virus (HIV) protease inhibitors (PIs) are widely used drugs whose effects are pharmacologically enhanced by ritonavir, a potent cytochrome P450 inhibitor. We reported previously that prophylactic postnatal ritonavir-PI therapy in HIV-exposed neonates was associated with increases in plasma 17-hydroxyprogesterone (17-OHP) and dehydroepiandrosterone sulfate (DHEA-S).

AIMS

To further investigate adrenal function in neonates and adolescents given ritonavir-PI.

METHODS

Adrenal function was assessed prospectively in 3 HIV-exposed neonates given short-term prophylactic treatment and 3 HIV-infected adolescents given long-term treatment. Plasma cortisol, 17-OHP, 17-OH-pregnenolone, DHEA-S, and androstenedione were measured before and after ACTH administration.

RESULTS

None of the patients had clinical signs of adrenal dysfunction. The only neonate exposed to ritonavir-PI in utero had up to 3-fold increases in plasma 17-OHP. Increases in 17-OH-pregnenolone of up to 3.1-fold were noted in 4 of the 6 patients, and all 6 patients had elevations in DHEA-S (up to 20.4-fold increase) and/or DHEA (up to 4.7-fold) and/or androstenedione (up to 5.2-fold). All these parameters improved after treatment completion.

CONCLUSION

Neonates and adolescents given ritonavir-PI exhibit a similar adrenal dysfunction profile consistent with an impact on multiple adrenal enzymes. These abnormalities require evaluation, given the potentially long exposure times.

Novel technique for constraining r-process (n, γ) reaction rates

A novel technique has been developed, which will open exciting new opportunities for studying the very neutron-rich nuclei involved in the r process. As a proof of principle, the γ spectra from the β decay of ^{76}Ga have been measured with the SuN detector at the National Superconducting Cyclotron Laboratory. The nuclear level density and γ-ray strength function are extracted and used as input to Hauser-Feshbach calculations. The present technique is shown to strongly constrain the ^{75}Ge(n,γ)^{76}Ge cross section and reaction rate.

Determining the rp-process flow through 56Ni: resonances in 57Cu(p,γ)58Zn identified with GRETINA

An approach is presented to experimentally constrain previously unreachable (p, γ) reaction rates on nuclei far from stability in the astrophysical rp process. Energies of all critical resonances in the (57)Cu(p,γ)(58)Zn reaction are deduced by populating states in (58)Zn with a (d, n) reaction in inverse kinematics at 75 MeV/u, and detecting γ-ray-recoil coincidences with the state-of-the-art γ-ray tracking array GRETINA and the S800 spectrograph at the National Superconducting Cyclotron Laboratory. The results reduce the uncertainty in the (57)Cu(p,γ) reaction rate by several orders of magnitude. The effective lifetime of (56)Ni, an important waiting point in the rp process in x-ray bursts, can now be determined entirely from experimentally constrained reaction rates.