Reactivation of Multidrug-Resistant HSV-1 in a Post-Allogenic Hematopoietic Stem Cell Transplant Patient: Dynamic Detection of the Rare A605V Mutation by Next-Generation Sequencing.

We present an immunocompromised patient with a multiresistant herpes simplex virus-1 reactivation with a rare mutation (A605V) in the viral DNA polymerase gene. Next-generation sequencing suggests the presence of multiple drug-resistant strains before treatment and altered ratios during treatment, affecting the clinical response to aciclovir and foscarnet.

Clofarabine added to intensive treatment in adult patients with newly diagnosed ALL: the HOVON-100 trial.

Clofarabine (CLO) is a nucleoside analog with efficacy in relapsed/refractory acute lymphoblastic leukemia (ALL). This randomized phase 3 study aimed to evaluate whether CLO added to induction and whether consolidation would improve outcome in adults with newly diagnosed ALL. Treatment of younger (18-40 years) patients consisted of a pediatric-inspired protocol, and for older patients (41-70 years), a semi-intensive protocol was used. Three hundred and forty patients were randomized. After a median follow-up of 70 months, 5-year event-free survival (EFS) was 50% and 53% for arm A and B (CLO arm). For patients ≤40 years, EFS was 58% vs 65% in arm A vs B, whereas in patients >40 years, EFS was 43% in both arms. Complete remission (CR) rate was 89% in both arms and similar in younger and older patients. Minimal residual disease (MRD) was assessed in 200 patients (60%). Fifty-four of 76 evaluable patients (71%) were MRD- after consolidation 1 in arm A vs 75/81 (93%) in arm B (P = .001). Seventy (42%) patients proceeded to allogeneic hematopoietic stem cell transplantation in both arms. Five-year overall survival (OS) was similar in both arms: 60% vs 61%. Among patients achieving CR, relapse rates were 28% and 24%, and nonrelapse mortality was 16% vs 17% after CR. CLO-treated patients experienced more serious adverse events, more infections, and more often went off protocol. This was most pronounced in older patients. We conclude that, despite a higher rate of MRD negativity, addition of CLO does not improve outcome in adults with ALL, which might be due to increased toxicity. This trial was registered at www.trialregister.nl as #NTR2004.

Clinical decision rule and D-dimer have lower clinical utility to exclude pulmonary embolism in cancer patients. Explanations and potential ameliorations.

Patients with malignancy frequently present with clinically suspected pulmonary embolism (PE). However, the safe and efficient combination of a clinical decision rule (CDR) and D-dimer test to rule out PE performs less well in patients with malignancy. We examined potential explanations and analysed whether elevating the D-dimer cut-off could improve the clinical utility. We used data on consecutive patients with suspected PE included in a multicenter management study. The performance of the Wells CDR and the D-dimer test was compared between patients with and without malignancy and multivariable analysis was used to compare the weights of the CDR variables. Furthermore, we combined the CDR (cut-off ≤4) with different D-dimer cut-off levels for the exclusion of PE. Of 3,306 patients with suspected PE, 475 (14%) had cancer. The Wells rule variables were less diagnostic in cancer patients. Increasing the D-dimer cut-off level to 700 µg/l for all ages or using an age-dependent cut-off resulted in an increase in the proportion of patients in whom PE could be excluded from 8.4% to 13% and 12%, respectively. The corresponding false-negative rates were 1.6% (95% confidence interval 0.3-8.7%) and 0.0% (0.0-6.3%). The Wells CDR and D-dimer perform less well in patients with suspected PE if they have cancer. Individual variables in the Wells rule are less diagnostic in cancer patients than in non-cancer patients with suspected PE. A CDR combined with an age-dependent D-dimer cut-off shows a modest improvement of the strategy in cancer patients.

A low molecular weight heparin inhibits experimental metastasis in mice independently of the endothelial glycocalyx.

BACKGROUND: Some low molecular weight heparins (LMWHs) prolong survival of cancer patients and inhibit experimental metastasis. The underlying mechanisms are still not clear but it has been suggested that LMWHs (at least in part) limit metastasis by preventing cancer cell-induced destruction of the endothelial glycocalyx. METHODOLOGY/PRINCIPAL FINDINGS: To prove or refute this hypothesis, we determined the net effects of the endothelial glycocalyx in cancer cell extravasation and we assessed the anti-metastatic effect of a clinically used LMWH in the presence and absence of an intact endothelial glycocalyx. We show that both exogenous enzymatic degradation as well as endogenous genetic modification of the endothelial glycocalyx decreased pulmonary tumor formation in a murine experimental metastasis model. Moreover, LMWH administration significantly reduced the number of pulmonary tumor foci and thus experimental metastasis both in the presence or absence of an intact endothelial glycocalyx. CONCLUSIONS: In summary, this paper shows that the net effect of the endothelial glycocalyx enhances experimental metastasis and that a LMWH does not limit experimental metastasis by a process involving the endothelial glycocalyx.

The role of activated protein C in cancer progression.

Activated protein C (APC) is best known as a natural anticoagulant that also has direct cell signaling properties which (among others) enhance vascular barrier function. We recently established the relevance of APC-induced barrier enhancement by showing that endogenous APC limits cancer cell extravasation. In line with this concept, repeated administration of exogenous APC reduced the number of experimental metastasis. It is thus tempting to speculate that exogenous APC administration would be a novel therapeutic avenue to fight cancer metastasis. The current review summarizes recent data on the role of the protein C pathway in cancer metastasis. It discusses the APC pathway as a potential novel target to influence cancer progression, but it also points to several limitations of APC administration in the setting of cancer cell metastasis.

Endogenous activated protein C limits cancer cell extravasation through sphingosine-1-phosphate receptor 1-mediated vascular endothelial barrier enhancement.

Activated protein C (APC) has both anticoagulant activity and direct cell-signaling properties. APC has been reported to promote cancer cell migration/invasion and to inhibit apoptosis and therefore may exacerbate metastasis. Opposing these activities, APC signaling protects the vascular endothelial barrier through sphingosine-1-phosphate receptor-1 (S(1)P(1))activation, which may counteract cancer cell extravasation. Here, we provide evidence that endogenous APC limits cancer cell extravasation, with in vivo use of monoclonal antibodies against APC. The protective effect of endogenous APC depends on its signaling properties. The MAPC1591 antibody that only blocks anticoagulant activity of APC does not affect cancer cell extravasation as opposed to MPC1609 that blocks anticoagulant and signaling properties of APC. Combined administration of anti-APC antibodies and S(1)P(1) agonist (SEW2871) resulted in a similar number of pulmonary foci in mice in presence and absence of APC, indicating that the protective effect of APC depends on the S(1)P(1) pathway. Moreover, endogenous APC prevents cancer cell-induced vascular leakage as assessed by the Evans Blue Dye assay, and SEW2871 treatment reversed MPC1609-dependent vascular leakage. Finally, we show that cancer cells combined with MPC1609 treatment diminished endothelial VE-cadherin expression. In conclusion, endogenous APC limits cancer cell extravasation because of S(1)P(1)-mediated VE-cadherin-dependent vascular barrier enhancement.