Absence of gene mutation in TRAIL receptor 1 (TRAIL-R1) and TRAIL receptor 2 (TRAIL-R2) in chronic myelogenous leukemia and myelodysplastic syndrome, and analysis of mRNA Expressions of TRAIL and TRAIL-related genes in chronic myelogenous leukemia

On the cytokines produced by human neutrophils in tumors

Although traditionally viewed as short-lived innate immunity cells, only playing a crucial role in host defense toward infections, neutrophils have recently become subject of a new wave of research in diverse areas including in tumors. Indeed, increasing experimental evidence indicate that neutrophils may directly or indirectly influence the tumor fate through the release of a wide array of molecules able to exert either pro-tumor or anti-tumor functions depending on the microenvironment milieu, including cytokines. This review therefore attempts to uncover the role that neutrophils play during the different steps of tumor development (from promotion to progression), as well as in anti-tumor responses, via cytokine production.

Haplotypes covering the TNFSF10 gene are associated with bronchial asthma

Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) is elevated in the airways of subjects with asthma and has been linked to the development of allergic airway disease by promoting STAT6-dependent T helper 2 cell (T(H) 2) effector functions. To determine whether single nucleotide polymorphisms (SNPs) in the TNFSF10 gene are associated with bronchial asthma we genotyped 498 Caucasian subjects living in Southern Germany for eight SNPs in the TNFSF10 by restriction fragment length polymorphism analysis. In contrast to single SNPs, haplotypes constructed from eight SNPs were robustly associated with asthma (p=0.00012). A small haplotype approach returned four alleles consisting of two (rs3136586/ rs3136598), three (rs12488654/rs3136586/rs3136598 and rs3136586/rs3136598/rs3136604), and four SNPs (rs12488654/ rs3136586/ rs3136598/ rs3136604) that were highly associated with asthma (p=0.00005, p=0.00008, p=0.00017 and p=0.00038). Combinations of SNPs in the TNFSF10 allele were strongly associated with asthma supporting the concept that TRAIL is important in the development of hallmark features of this disease.

Establishment and characterization of a novel imatinib-sensitive chronic myeloid leukemia cell line MYL, and an imatinib-resistant subline MYL-R showing overexpression of Lyn

In chronic myeloid leukemia (CML), resistance to imatinib is diverse. In addition to BCR-ABL-dependent mechanisms, BCR-ABL-independent mechanisms have been proposed. Here we established and characterized novel CML cell lines, an imatinib-sensitive cell line, MYL, and an imatinib-resistant subline, MYL-R. Treatment with imatinib inhibited phosphorylation of BCR-ABL and CrkL in both MYL and MYL-R, even though imatinib-induced apoptosis was preferentially observed in MYL than MYL-R, indicating that the resistance is based on a BCR-ABL-independent mechanism. MYL-R showed elevated expressions of Lyn mRNA, Lyn protein, phosphorylated Lyn, and phosphorylated STAT5. Silencing of Lyn by short-interfering RNA (siRNA) in MYL-R, but not in MYL, induced significant growth-inhibition, increased caspase-3 activity, and induced partial recovery from imatinib-resistance. Expression of Bcl-2, previously reported to be associated with Lyn-mediated resistance, was not elevated in MYL-R. Expression of Bim, which plays an important role in imatinib-induced cell-killing, was not suppressed in MYL-R. These results imply that diverse mechanisms of resistance exist among cell types. Treatment of MYL-R cells with various reagents known to have anti-leukemic activity revealed that zoledronic acid and the farnesyl transferase inhibitor (SCH 66336) showed strong synergism with imatinib; interferon alpha, PP2, CGP76030, and FK228 (depsipeptide) showed synergism; whereas soluble TRAIL and As2O3 showed additivity or antagonism, and 17-AAG and radicicol showed antagonism. Treatment with either PP2 or zoledronic acid induced greater growth-reduction in MYL-R than MYL. Taken together, Lyn may play an important role in imatinib-resistance in MYL-R. Some novel reagents, including siRNA targeting Lyn, may have good potential to overcome this resistance.

Treatment with IFNalpha in vivo up-regulates serum-soluble TNF-related apoptosis inducing ligand (sTRAIL) levels and TRAIL mRNA expressions in neutrophils in chronic myelogenous leukemia patients

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is an interferon alpha (IFNalpha)-induced, apoptosis-inducing molecule. TRAIL could be one of the reagents for therapeutic use in combination with imatinib in chronic myeloid leukemia (CML). Here we examined serum-soluble TRAIL (sTRAIL) levels in CML patients either before or during therapies with IFNalpha or imatinib. In untreated CML patients, serum sTRAIL was detectable and the levels were substantially comparable with those in healthy donors. sTRAIL levels significantly increased in patients during IFNalpha therapy, but not at all in patients during imatinib therapy. TRAIL mRNA expressions in neutrophils in CML patients undergoing IFNalpha therapy was significantly elevated when compared with those in patients prior to therapy. TRAIL mRNA expressions were also detectable in CD34-positive cells in bone marrow, and the levels increased in patients during IFNalpha therapy. In vitro IFNalpha stimulation of CML neutrophils increased intracellular TRAIL rather than cell-surface TRAIL, and the secretion of sTRAIL in the culture supernatant was observed. This sTRAIL secretion was augmented with lipopolysaccharide (LPS) stimulation only in IFNalpha-primed neutrophils, whereas LPS alone had no effect. Taken together, in vivo IFNalpha treatment provokes the release of sTRAIL when administered systematically in CML patients. The main source of the IFNalpha-induced serum sTRAIL may be neutrophils in CML, and sTRAIL may be one of the mechanisms of the anti-proliferative action of IFNalpha on CML. These findings give another rationale for the use of IFNalpha or recombinant sTRAIL in CML, and also implicate the potential importance of neutrophils in tumor immunosurveillance.

Centennial review of corneal transplantation

Abstract One hundred years ago, on 7 December 1905, Dr Eduard Zirm performed the world's first successful human corneal transplant. This significant milestone was achieved only after many decades of unsuccessful trial and error; however, it did not lead to relatively 'routine' keratoplasty success for several more decades. The idea of replacing an opaque cornea had been suggested for centuries, and had stimulated theoretical approaches to the problem by many esteemed physicians throughout history. However, little practical progress was made in the ultimate realization of the dream until the 19th century when pioneering surgeons pursued extensive studies in relation to both animal and human 'keratoplasty'. Clinical progress and scientific insight developed slowly, and it was ultimately due to parallel advances in medicine such as anaesthesia and antisepsis that Zirm's success was finally achieved. Key concepts were enshrined such as the use of fresh tissue from the same species, careful placement and handling of tissue, and the development of specialized instrumentation such as the circular trephine. In the latter half of the 20th century, many 'masters' of corneal surgery evolved significant refinements in technique and instrumentation with the development of corticosteroids, antibiotics, surgical microscopes, improved trephines, viscoelastics and suture materials, that enable this delicate procedure to be routinely performed with the prospect of success. There are still limitations to corneal transplantation, and corneal allograft rejection still poses the greatest challenge to the modern corneal surgeon. In the foreseeable future it may be in the laboratory, rather than the theatre, that further milestones will be achieved. This review aims to highlight the significant milestones in the rich history of corneal transplantation, and to pay tribute to the many inspired and dedicated individuals involved in the development of keratoplasty to a point where the procedure is now a standard tool in the repertoire of ophthalmic surgery and more than a million people have enjoyed restoration of useful sight.

Interferon-activated neutrophils store a TNF-related apoptosis-inducing ligand (TRAIL/Apo-2 ligand) intracellular pool that is readily mobilizable following exposure to proinflammatory mediators

Neutrophils are versatile cells, which play a role, not only in inflammatory processes but also in immune and antitumoral responses. Recently, we have reported that interferon (IFN)-activated neutrophils are able to release biologically active tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL/APO2 ligand), a molecule exerting selective, apoptotic activities toward tumor and virus-infected cells, as well as immunoregulatory functions on activated T lymphocytes. Herein, we show that only a minor fraction of the total TRAIL, newly synthesized by IFN-activated neutrophils within 24 h, is released outside, the rest being retained intracellularly, mainly in secretory vesicles and light membrane fractions. We demonstrate that the intracellular pool of TRAIL present in IFN-pretreated neutrophils is rapidly mobilizable to the cell surface and can be secreted following exposure to proinflammatory mediators such as TNF-alpha, lipopolysaccharide, formyl-methionyl-leucyl-phenylalanine, CXC chemokine ligand 8/interleukin-8, insoluble immunocomplexes, and heat shock protein Gp96. These various proinflammatory agonists functioned as effective secretagogue molecules only, in that they failed to augment TRAIL mRNA expression or TRAIL de novo synthesis in freshly isolated neutrophils or cultured with or without IFN. In addition, supernatants from IFN-treated neutrophils stimulated with proinflammatory mediators induced the apoptosis of target cells more effectively than supernatants from neutrophils activated with IFNs alone. Collectively, our results uncover a novel mechanism, whereby the release of soluble TRAIL by neutrophils can be greatly amplified and further reinforce the notion that neutrophils are important cells in tumor surveillance and immunomodulation.