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Background: Brain tumours are recognised as one of the most difficult cancers to diagnose because presenting symptoms, such as headache, cognitive symptoms, and seizures, may be more commonly attributable to other, more benign conditions. Interventions to reduce the time to diagnosis of brain tumours include national awareness initiatives, expedited pathways, and protocols to diagnose brain tumours, based on a person's presenting symptoms and signs; and interventions to reduce waiting times for brain imaging pathways. If such interventions reduce the time to diagnosis, it may make it less likely that people experience clinical deterioration, and different treatment options may be available., Objectives: To systematically evaluate evidence on the effectiveness of interventions that may influence: symptomatic participants to present early (shortening the patient interval), thresholds for primary care referral (shortening the primary care interval), and time to imaging diagnosis (shortening the secondary care interval and diagnostic interval). To produce a brief economic commentary, summarising the economic evaluations relevant to these interventions., Search Methods: For evidence on effectiveness, we searched CENTRAL, MEDLINE, and Embase from January 2000 to January 2020; Clinicaltrials.gov to May 2020, and conference proceedings from 2014 to 2018. For economic evidence, we searched the UK National Health Services Economic Evaluation Database from 2000 to December 2014., Selection Criteria: We planned to include studies evaluating any active intervention that may influence the diagnostic pathway, e.g. clinical guidelines, direct access imaging, public health campaigns, educational initiatives, and other interventions that might lead to early identification of primary brain tumours. We planned to include randomised and non-randomised comparative studies. Included studies would include people of any age, with a presentation that might suggest a brain tumour., Data Collection and Analysis: Two review authors independently assessed titles identified by the search strategy, and the full texts of potentially eligible studies. We resolved discrepancies through discussion or, if required, by consulting another review author., Main Results: We did not identify any studies for inclusion in this review. We excluded 115 studies. The main reason for exclusion of potentially eligible intervention studies was their study design, due to a lack of control groups. We found no economic evidence to inform a brief economic commentary on this topic., Authors' Conclusions: In this version of the review, we did not identify any studies that met the review inclusion criteria for either effectiveness or cost-effectiveness. Therefore, there is no evidence from good quality studies on the best strategies to reduce the time to diagnosis of brain tumours, despite the prioritisation of research on early diagnosis by the James Lind Alliance in 2015. This review highlights the need for research in this area., (Copyright © 2020 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.)

Olumacostat glasaretil (OG) is a small molecule inhibitor of acetyl coenzyme A (CoA) carboxylase (ACC), the enzyme that controls the first rate-limiting step in fatty acid biosynthesis. Inhibition of ACC activity in the sebaceous glands is designed to substantially affect sebum production, because over 80% of human sebum components contain fatty acids. OG inhibits de novo lipid synthesis in primary and transformed human sebocytes. TrueMass Sebum Panel analyses showed a reduction in saturated and monounsaturated fatty acyl chains across lipid species, including di- and triacylglycerols, phospholipids, cholesteryl esters, and wax esters in OG-treated sebocytes. There was no shift to shorter acyl chain lengths observed, suggesting that the fatty acid chain elongation process was not affected. OG is a pro-drug of the ACC inhibitor 5-(tetradecyloxy)-2-furoic acid and was designed to enhance delivery in vivo. Topical application of OG but not 5-(tetradecyloxy)-2-furoic acid significantly reduced hamster ear sebaceous gland size, indicating that this pro-drug approach was critical to obtain the desired activity in vivo. High-performance liquid chromatography analyses of hamster ear extracts showed that OG treatment increased ACC levels and the ratio of acetyl-CoA to free CoA in these animals, indicating increased fatty acid oxidation. These changes are consistent with ACC inhibition. Matrix-assisted laser desorption/ionization imaging showed that OG applied onto Yorkshire pig ears accumulated in sebaceous glands relative to the surrounding dermis. Sebaceous gland ACC represents an attractive therapeutic target given its central role in formation of sebum, a key factor in acne pathogenesis., (Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.)

Coxsackievirus B3, a cytopathic virus in the family Picornaviridae, induces degenerative changes in host cell morphology. Here we demonstrate cytochrome c release and caspases-2, -3, -6, -7, -8, and -9 processing. Enforced Bcl-2 and Bcl-xL expression markedly reduced release of cytochrome c, presentation of the mitochondrial epitope 7A6, and depressed caspase activation following infection. In comparison, cell death using TRAIL ligand caused caspase-8 processing prior to cytochrome c release and executioner caspases and cell death was only partially rescued by Bcl-2 and Bcl-xL overexpression. Disruption of the mitochondrial inner membrane potential following CVB3 infection was not inhibited by zVAD.fmk treatment. Bcl-2 or Bcl-xL overexpression or zVAD.fmk treatment delayed the loss of host cell viability and decreased progeny virus release following infection. Our data suggest that mitochondrial release of cytochrome c may be an important early event in caspase activation in CVB3 infection, and, as such, may contribute to the loss of host-cell viability and progeny virus release.

Pyropheophorbide-a methylester (PPME) is a second generation of photosensitizers used in photodynamic therapy (PDT). We demonstrated that PPME photosensitization triggered apoptosis of colon cancer cells as measured by using several classical parameters such as DNA laddering, PARP cleavage, caspase activation and mitochondrial release of cytochrome c. Preincubation of cells with N-acetyl cysteine (NAC) or pyrolidine dithiocarbamate (PDTC) protected against apoptosis mediated by PPME photosensitization showing that reactive oxygen species (ROS) are involved as second messengers. On the other hand, photosensitization carried out in the presence of deuterium oxide (D2O) which enhances singlet oxygen (1O2) lifetime only increases necrosis without affecting apoptosis. Since PPME was localized in the endoplasmic reticulum (ER)/Golgi system and lysosomes, other messengers than ROS were tested such as calcium, Bid, Bap31, phosphorylated Bcl-2 and caspase-12 but none was clearly identified as being involved in triggering cytochrome c release from mitochondria. On the other hand, we demonstrated that the transduction pathways leading to NF-kappaB activation and apoptosis were clearly independent although NF-kappaB was shown to counteract apoptosis mediated by PPME photosensitization.

Photodynamic therapy (PDT) is under investigation for the treatment of intimal hyperplastia in conditions such as atherosclerosis and restenosis. Although smooth muscle cells (SMCs) may be a key target for treatment, the effects of PDT on these cells are poorly characterized. In the present study, apoptosis was induced in primary human aortic SMCs by the combination of the photosensitizer verteporfin and visible light. After PDT, an increase in mitochondrial cytochrome c (cyt c) and apoptosis-inducing factor (AIF) levels were detected in the cytosol immediately and their levels increased steadily up to 2 hours. Cytosolic levels of the pro-apoptotic Bcl-2 family member Bax decreased reciprocally throughout this period, but this change did not occur before cyt c release. Confocal microscopy revealed a diffuse staining pattern of cyt c within apoptotic cells as compared to a distinct mitochondrial staining in normal cells. AIF translocated from mitochondria to the nucleus during the progression of apoptosis. After cyt c release, caspase-9 and caspase-3 processing was visible by 1 hour and caspase-6, -7, and -8 processing was apparent by 2 hours after PDT. In summary, these results demonstrate for the first time the cellular redistribution of mitochondrial AIF during SMC apoptosis, as well as the early release of cyt c and the subsequent activation of multiple caspases during PDT-induced SMC apoptosis.

The nuclear factor-kappa B (NF-kappaB) gene transactivator serves in the formation of immune, inflammatory, and stress responses. In quiescent cells, NF-kappaB principally resides within the cytoplasm in association with inhibitory kappa (IkappaB) proteins. The status of IkappaB and NF-kappaB proteins was evaluated for promyelocytic leukemia HL-60 cells treated at different intensities of photodynamic therapy (PDT). The action of the potent photosensitizer, benzoporphyrin derivative monoacid ring A (verteporfin), and visible light irradiation were assessed. At a verteporfin concentration that produced the death of a high proportion of cells after light irradiation, evidence of caspase-3 and caspase-9 processing and of poly(ADP-ribose) polymerase cleavage was present within whole cell lysates. The general caspase inhibitor Z-Val-Ala-Asp-fluoromethylketone (ZVAD.fmk) effectively blocked these apoptosis-related changes. Recent studies indicate that IkappaB proteins may be caspase substrates during apoptosis. However, the level of IkappaBbeta was unchanged for HL-60 cells undergoing PDT-induced apoptosis. IkappaBalpha levels decreased during PDT-induced apoptosis, though ZVAD.fmk did not affect this change. At a less intensive level of photosensitization, cellular IkappaBalpha levels were transiently depressed after PDT. At these times, p50 and RelA NF-kappaB species were increased within nuclear extracts, as revealed by electrophoretic mobility supershift assays. HL-60 cells transiently transfected with a kappaB-luciferase reporter construct exhibited elevated luciferase activity after PDT or treatment with tumor necrosis factor-alpha, a well-characterized NF-kappaB activator. Productive NF-kappaB activation and associated gene transcription may influence the phenotype and behavior of cells exposed to less intensive PDT regimens. However, IkappaBalpha is not subject to caspase-mediated degradation as a component of PDT-induced apoptosis. (Blood. 2000;95:256-262)

Although the executioner phase of apoptosis has been well defined in many cell types, the subcellular events leading to apoptosis in endothelial cells remain undefined. In the current study, apoptosis was induced in primary human umbilical venous endothelial cells by the photosensitizer verteporfin and light. Release of mitochondrial cytochrome c into the cytosol was detectable immediately and accumulated over 2 hours after treatment while cytosolic levels of the proapoptotic Bcl-2 family member, Bax, decreased reciprocally over the same time period. Cleavage of another proapoptotic Bcl-2 family member, Bid, was observed by 2 hours after treatment. Although Bid cleavage has been shown to occur as an upstream event responsible for inducing cytochrome c release, we demonstrate that Bid cleavage can also occur after cytochrome c release. Activation of caspases 2, 3, 6, 7, 8, and 9 occurred following the release of cytochrome c, and cleavage of downstream substrates was observed. In summary, endothelial cell death involves the cellular redistribution of Bax and cytochrome c, followed by the activation of multiple caspases which manifest the apoptotic phenotype.

Treatment with the photosensitizer benzoporphyrin derivative monoacid ring A (BPD-MA, verteporfin) followed by irradiation with visible light induces apoptosis in human acute myelogenous leukaemia HL-60 cells. Photoactivation of BPD-MA induces procaspase 3 (CPP32/Yama/apopain) and procaspase 6 (Mch2) cleavage into their proteolytically active subunits in these cells. The Bcl-2 proto-oncogene product has been shown to protect cells from a number of proapoptotic stimuli. In the present study, the influence of Bcl-2 overexpression on cellular resistance to photoactivation of BPD-MA was studied. Overexpression of Bcl-2 in HL-60 cells prevented apoptosis-related events including caspase 3 and 6 activation, poly(ADP-ribose) polymerase cleavage and the formation of hypodiploid DNA produced by BPD-MA (0-200 ng ml(-1)) and light. However, Bcl-2 overexpression was less effective at preventing cell death that occurred after photoactivation at high levels (50-100 ng ml(-1)) compared with lower doses (10-25 ng ml(-1)) of BPD-MA. These results indicate that caspase 3 and 6 activation and their regulation by Bcl-2 may play important roles in photodynamic therapy (PDT)-induced cell killing.

Photodynamic therapy (PDT) is a clinical approach that utilizes light-activated drugs for the treatment of a variety of pathologic conditions. The initiating events of PDT-induced apoptosis are poorly defined. It has been shown for other proapoptotic stimuli that the integral endoplasmic reticulum protein Bap31 is cleaved by caspases 1 and 8, but not by caspase-3. Further, a 20 kDa Bap31 cleavage fragment is generated which can induce apoptosis. In the current report, we sought to determine whether Bap31 cleavage and generation of p20 is an early event in PDT-induced apoptosis. The mitochondrial release of cytochrome c, involvement of caspases 1, 2, 3, 4, 6, 7, 8, and 10 and the status of several known caspase substrates, including Bap31, were evaluated in PDT-treated HeLa cells. Cytochrome c appeared in the cytosol immediately following light activation of the photosensitizer benzoporphyrin derivative monoacid ring A. Activation of caspases 3, 6, 7, and 8 was evident within 1-2 h post PDT. Processing of caspases 1, 2, 4, and 10 was not observed. Cleavage of Bap31 was observed at 2-3 h post PDT. The caspase-3 inhibitor DEVD-fmk blocked caspase-8 and Bap31 cleavage suggesting that caspase-8 and Bap31 processing occur downstream of caspase-3 activation in PDT-induced apoptosis. These results demonstrate that release of mitochondrial cytochrome c into the cytoplasm is a primary event following PDT, preceding caspase activation and cleavage of Bap31. To our knowledge, this is the first example of a chemotherapeutic agent inducing caspase-8 activation and demonstrates that caspase-8 activation can occur after cytochrome c release.

Coxsackievirus B3 (CVB3), an enterovirus in the family Picornaviridae, induces cytopathic changes in cell culture systems and directly injures multiple susceptible organs and tissues in vivo, including the myocardium, early after infection. Biochemical analysis of the cell death pathway in CVB3-infected HeLa cells demonstrated that the 32-kDa proform of caspase 3 is cleaved subsequent to the degenerative morphological changes seen in infected HeLa cells. Caspase activation assays confirm that the cleaved caspase 3 is proteolytically active. The caspase 3 substrates poly(ADP-ribose) polymerase, a DNA repair enzyme, and DNA fragmentation factor, a cytoplasmic inhibitor of an endonuclease responsible for DNA fragmentation, were degraded at 9 h following infection, yielding their characteristic cleavage fragments. Inhibition of caspase activation by benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (ZVAD.fmk) did not inhibit the virus-induced cytopathic effect, while inhibition of caspase activation by ZVAD.fmk in control apoptotic cells induced by treatment with the porphyrin photosensitizer benzoporphyrin derivative monoacid ring A and visible light inhibited the apoptotic phenotype. Caspase activation and cleavage of substrates may not be responsible for the characteristic cytopathic effect produced by picornavirus infection yet may be related to late-stage alterations of cellular homeostatic processes and structural integrity.

In recent years, intense research has been directed towards understanding molecular mechanisms involved in viral pathogenesis. It is now known that many viruses manipulate host defense mechanisms to prevent apoptosis in order to maximize viral replication. Towards the end of their replication cycle, certain viruses direct the synthesis of proteins that induce apoptosis or cell lysis thereby facilitating viral release from the cell. The present review summarizes the current understanding of interactions between viral proteins and the host cell death machinery.

Photodynamic therapy (PDT) is a clinically effective cancer treatment. For human promyelocytic leukemia HL-60 cells, cleavage of pro-caspase-3 (CPP32/Yama/apopain) into its proteolytically active subunits rapidly follows the photodynamic treatment of these cells with cytotoxic levels of the photosensitizer benzoporphyrin derivative monoacid ring A and visible light. Cleavage of a recently identified cytosolic 45 kDa protein, DNA fragmentation factor (DFF), is required for endonuclease activation leading to DNA fragmentation. In the present study, DFF was rapidly processed following PDT. Overexpression of the anti-apoptotic Bcl-X(L) gene in HL-60 cells prevented PDT-induced caspase activation, DFF cleavage and DNA fragmentation. These results demonstrate for the first time an example of chemotherapeutic drug-induced activation of DFF and its regulation by Bcl-X(L).

Caspases have been shown to play a crucial role in apoptosis induced by various deleterious and physiologic stimuli. In this study, we show for the first time that photodynamic therapy (PDT), using benzoporphyrin derivative monoacid ring A (BPD-MA, verteporfin) as the photosensitizer, induces the complete cleavage and subsequent activation of caspase-3 (CPP32/Yama/Apopain) but not caspase-1 (ICE) in human promyelocytic leukemia HL-60 cells. Poly(ADP-ribose) polymerase (PARP) and the catalytic subunit of DNA dependent protein kinase (DNA PK(CS)) were cleaved within 60 min of light activation of BPD-MA. The general caspase inhibitor Z-Asp-2,6 dichlorobenzoyloxymethylketone (Z-Asp-DCB) blocked PARP cleavage while the serine protease inhibitors 3,4-dichloroisocoumarin (DCI) and N-tosyl-lysyl chloromethyl ketone (TLCK) blocked the cleavage of caspase-3 suggesting that they act upstream of caspase-3 activation. All three inhibitors were able to block DNA fragmentation that was induced by treatment with BPD-MA followed by light application. These studies demonstrate that protease activity, particularly that of caspase-3, is triggered in HL-60 cells treated with lethal levels of BPD-MA and visible light.

A proposed definition of juvenile psoriatic arthritis (JPsA) was used to identify definite or probable JPsA in 35 children. Definite JPsA (24 patients) was defined as arthritis associated, but not necessarily coincident, with a typical psoriatic rash, or arthritis plus at least 3 of 4 minor criteria: dactylitis, nail pitting, psoriasis-like rash, or family history of psoriasis. Probable JPsA (11 patients) was defined as arthritis plus 2 of the minor criteria. In 33 of 35 patients, the onset of arthritis was pauciarticular, but the disease followed a polyarticular course in 23 of 35. Chronic anterior uveitis (6 of 35), antinuclear antibodies (22 of 35), anticollagen antibodies (10 of 35), HLA-DR4 (2 of 28), and HLA-DR8 (5 of 28) occurred with frequencies similar to those seen in patients with juvenile rheumatoid arthritis. JPsA may have more in common with juvenile rheumatoid arthritis than with the seronegative spondylarthropathies with which it is traditionally associated.

Studies of immunity to bovine soluble retinal antigen (antigen S) were carried out using serum and peripheral blood lymphocytes from children with juvenile rheumatoid arthritis and chronic anterior uveitis (JRA-uveitis), children with JRA alone, children with nonrheumatic diseases, and controls who had no ocular or rheumatic disease. Enzyme-linked immunosorbent assay and the lymphocyte transformation assay were used to determine immunity. Antibody to antigen S was present significantly more frequently in children with JRA-uveitis than in children with JRA alone, children with nonrheumatic disorders, or controls. These latter groups did not differ in positivity for this antibody. Lymphocyte transformation occurred more frequently in children with JRA-uveitis than in children with JRA alone or controls. Children with JRA alone and controls had similar frequencies of lymphocyte transformation positivity. Enzyme-linked immunosorbent assay positivity and lymphocyte transformation positivity tended to occur in different children. Children with JRA-uveitis who had HLA-B35 had the highest frequency of antibody to antigen S. Immunity to antigen S may be the result of ocular damage by mechanisms other than a pathogenic mechanism per se.