Marrow transplantation for children with acute lymphoblastic leukemia in second remission

Fifty-seven children between the ages of 3 and 17 years with acute lymphoblastic leukemia (ALL) in chemotherapy-induced second bone marrow remission were given cyclophosphamide, total body irradiation, and bone marrow transplants from HLA-matched donors. Sixteen died of transplant- related complications. Eighteen relapsed between 56 and 833 days after transplantation, and 16 died of leukemia. Two survive in remission off treatment following chemotherapy. Twenty-three survive in continuous remission from 1.4 to 10.4 years after transplantation and the actuarial analysis shows disease-free survival of 40% with a plateau extending from 2.5 to 10.4 years.     

Effect of recombinant human interleukin-6 (rhIL-6) and rhIL-3 on hematopoietic regeneration as demonstrated in a nonhuman primate chemotherapy model

Using a recently developed hepsulfam-induced pancytopenia model in rhesus macaques, we have studied the effects of recombinant human interleukin-6 (rhIL-6) and rhIL-3 on marrow regeneration. Control animals were given hepsulfam (1.5 g/m2 by a single 30-minute intravenous [i.v.] injection, n = 4), while study animals received hepsulfam followed by rhIL-6, rhIL-3, or a combination of rhIL-6 and rhIL-3 (n = 3 per study group). Each cytokine was administered by once- daily subcutaneous (SC) injection (15 micrograms/kg/d) for 3 weeks beginning the day after chemotherapy (days 2 through 22). Mean platelet counts in control animals were < 100,000/microL on days 15 through 24, with 50% of the counts < 50,000/microL and two of four animals requiring platelet transfusion. In the rhIL-6- and rhIL-6/rhIL-3- treated groups, the nadir mean platelet counts were 164,000 +/- 58,700/microL and 162,300 +/- 23,800/microL, respectively, and occurred on day 15. Platelet counts in the rhIL-3-treated group were similar to those in controls. Mean absolute neutrophil counts (ANCs) < 1,000/microL occurred on days 10 through 29 in control animals, days 8 through 15 in rhIL-6-treated animals, and days 6 through 8 and 13 in rhIL-6/rhIL-3-treated animals. The frequency of ANCs < 500/microL was significantly less in the rhIL-6- and rhIL-6/rhIL-3-treated groups versus control groups (2.7 +/- 0.6 and 2.0 +/- 1.0 vs 7.0 +/- 1.4 occurrences, respectively; P < .05). rhIL-3-treated animals had ANCs similar to those in controls; one animal died with septicemia on day 21. Monkeys receiving rhIL-6 were significantly more anemic during the cytokine administration period; however, the anemia resolved by day 24. Coadministration of rhIL-3 and rhIL-6 partially corrected the anemia. The data indicate that rhIL-6 prevents significant thrombocytopenia and shortens the neutropenic period in this chemotherapy model.     

A TNF receptor 2 agonist ameliorates neuropathology and improves cognition in an Alzheimer’s disease mouse model

Tumor necrosis factor-α (TNF-α) is a pleiotropic, proinflammatory cytokine related to different neurodegenerative diseases, including Alzheimer’s disease (AD). Although the linkage between increased TNF-α levels and AD is widely recognized, TNF-α–neutralizing therapies have failed to treat AD. Previous research has associated this with the antithetic functions of the two TNF receptors, TNF receptor 1, associated with inflammation and apoptosis, and TNF receptor 2 (TNFR2), associated with neuroprotection. In our study, we investigated the effects of specifically stimulating TNFR2 with a TNFR2 agonist (NewStar2) in a transgenic Aβ-overexpressing mouse model of AD by administering NewStar2 in two different ways: centrally, via implantation of osmotic pumps, or systemically by intraperitoneal injections. We found that both centrally and systemically administered NewStar2 resulted in a drastic reduction in amyloid β deposition and β-secretase 1 expression levels. Moreover, activation of TNFR2 increased microglial and astrocytic activation and promoted the uptake and degradation of Aβ. Finally, cognitive functions were also improved after NewStar2 treatment. Our results demonstrate that activation of TNFR2 mitigates Aβ-induced cognitive deficits and neuropathology in an AD mouse model and indicates that TNFR2 stimulation might be a potential treatment for AD.

Tumor necrosis factor-α (TNF-α) is a master proinflammatory cytokine involved in the regulation of innate and adaptive immunity (1). TNF-α plays a crucial role in various autoimmune and neurological disorders, including Alzheimer’s disease (AD) (2, 3). TNF-α–neutralizing therapeutics have been approved for the treatment of different inflammatory and autoimmune diseases, like rheumatoid arthritis or plaque psoriasis (4). However, the treatment of neurological disorders with TNF-α–neutralizing drugs led to inconclusive or even detrimental results (5–8). The latter could be explained, at least partly, by the different functions of the two receptors of TNF: on the one hand, stimulation of cytotoxic and strongly inflammatory pathways by TNF receptor 1 (TNFR1) in response to soluble TNF (sTNF) or membrane TNF (mTNF) or, on the other hand, activation of TNF receptor 2 (TNFR2) by mTNF eliciting pro- and antiinflammatory effects but also neuroprotective functions and tissue regeneration (9, 10).As a consequence, several studies aimed at selective targeting of TNFR1 or TNFR2, instead of completely inhibiting TNF-α. First, targeting TNFR1 by using specific TNFR1 antagonists or sTNF inhibitors resulted in amelioration of inflammation and apoptosis in various in vivo neurodegenerative disease models, such as models of multiple sclerosis (11, 12), Parkinson’s disease (13), and AD (14, 15). Second, targeting TNFR2 by specific TNFR2 agonists exerted an enhancement in neuroregeneration and tissue homeostasis in vitro (16) as well as in in vivo models (17). Therefore, specific targeting of TNFR1 and/or TNFR2 offers a promising new therapeutic avenue.However, clinical and preclinical studies on the effect of specific therapeutic targeting of TNFR2 in AD are lacking. It is acknowledged that during AD, the deposition of Aβ plaques, one of the main hallmarks of AD pathogenesis, occurs as a consequence of an imbalance between Aβ production and clearance (18). The β-secretase 1 (BACE-1) is mainly responsible for the production of toxic Aβ peptides, whereas uptake and degradation of these peptides are achieved by glial cells in the central nervous system (CNS), such as microglia and astrocytes (19, 20). Microglia are the resident macrophages of the CNS and their function is to constantly survey their environment and react to any detected insult, such as tissue damage or pathogen infection (21). Microglia are also involved in tissue repair and maintaining brain homeostasis. Moreover, microglia have been found to be essential for Aβ clearance in AD mouse models (20). It has been reported that in the context of AD, BACE-1 expression is increased, and the presence of Aβ plaques impairs the phagocytic activity of microglia (22, 23). These events could lead to an overproduction of Aβ accompanied by reduced Aβ clearance, which may partly lead to the observed pathogenesis of AD.Previous studies have proven that TNFR2 activation is neuroprotective in different disease models; however, it remains to be established whether TNFR2 stimulation has a protective effect against Aβ-mediated neuropathology and amyloid deposition and if this could improve cognitive functions. Therefore, in this study, we tested the hypothesis that selective stimulation of TNFR2 is able to abrogate Aβ-associated neuropathology and cognitive impairments.     

Genomic profile of pseudomyxoma peritonei analyzed using next‐generation sequencing and immunohistochemistry

Pseudomyxoma peritonei (PMP) is a relatively rare clinical syndrome characterized by neoplastic epithelial cells growing in the peritoneal cavity and secreting mucinous ascites. Our aim was to explore the molecular events behind this fatal but under‐investigated disease. We extracted DNA from 19 appendix‐derived PMP tumors and nine corresponding normal tissues, and analyzed the mutational hotspot areas of 48 cancer‐related genes by amplicon‐based next‐generation sequencing (NGS). Further, we analyzed the protein expression of V600E mutated BRAF, MLH1, MSH2, MSH6 and p53 from a larger set of PMP tumors (n = 74) using immunohistochemistry. With NGS, we detected activating somatic KRAS mutations in all of the tumors studied. GNAS was mutated in 63% of the tumors with no marked difference between low‐grade and high‐grade tumors. Only one (5.3%) tumor showed oncogenic PIK3CA mutation, one showed oncogenic AKT1 mutation, three (15.8%) showed SMAD4 mutations and none showed an APC mutation. P53 protein was aberrantly expressed in higher proportion of high‐grade tumors as compared with low‐grade ones (31.3 vs. 7.1%, respectively; p = 0.012) and aberrant expression was an independent factor for reduced overall survival (p = 0.002). BRAF V600E mutation was only found in one (1.4%) high‐grade tumor by immunohistochemistry (n = 74). All the studied tumors expressed mismatch repair proteins MLH1, MSH2 and MSH6. Our results indicate that KRAS mutations are evident in all and GNAS mutations in most of the PMPs, but BRAF V600E, PIK3CA and APC mutations are rare. Aberrantly expressed p53 is associated with high‐grade histology and reduced survival.     

Biliary lithotripsy: early observations in 106 patients. Work in progress

One hundred six patients underwent extracorporeal shock wave lithotripsy for cholelithiasis. Of these, 28 patients underwent cholangiographically guided lithotripsy for bile duct stones to assist nonoperative stone removal by endoscopic or radiologic intervention. Fragmentation occurred in 20 of 28 cases (71%) with an average of two lithotripsy sessions. Hemobilia was observed in four patients (14%) for a 24-hour period. Seventy-eight of the 106 were outpatients with symptomatic cholecystolithiasis with one to five calculi who underwent cholecystographic or ultrasound-(US) guided shock wave lithotripsy as definitive therapy. US examination showed stone fragmentation in 86% of cases. With an average of 1.6 treatment sessions and 4,750 shocks, fragments were 4 mm or smaller in 46% of patients. Nine percent of patients had no fragments after an average of 10 weeks, but long-term follow-up is not yet available. Two patients developed acute pancreatitis attributable to fragment passage and one patient acute cholecystitis, likely due to cystic duct obstruction by a fragment.