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The 2010 7th International Melanoma Congress sponsored by the Society for Melanoma Research and held in Sydney, Australia, was held together with the International Melanoma and Skin Cancer Centers group and the International Melanoma Pathology Study Group. As a consequence, there were over 900 registrants that included a wide range of clinicians (surgeons, medical oncologists, dermatologists) specialising in the management of melanoma as well as scientists and students carrying out laboratory-based research in melanoma. There was a general consensus that this grouping of clinicians, pathologists and scientists was mutually advantageous and plans are afoot to continue this grouping in future meetings. The meeting was dominated by the advances being made in treatment of melanoma with selective BRAF inhibitors but interest in epithelial mesenchymal transition and phenotypic changes in melanoma was apparent in many of the talks. The authors have attempted to capture many of the new developments in melanoma research but apologize to those speakers and poster presenters who had equally important findings not captured in these summaries. [ABSTRACT FROM AUTHOR]

In the present study, we have examined whether treatment of patients with metastatic melanoma with matured dendritic cell (DC) vaccines with or without low dose IL-2 may improve treatment outcomes. Sixteen patients received DC vaccines (DCs) sensitized with autologous melanoma lysates and 18 patients received DCs sensitized with peptides from gp100, MART-1, tyrosinase, MAGE-3.A2, MAGE-A10 and NA17. IL-2 was given subcutaneously (sc) at 1 MU/m2 on the second day after each injection for 5–14 days in half of each group. DCs were given by intranodal injection. There were 2 partial responses (PR) and 3 with stable disease (SD) in the nine patients receiving DCs + peptides + IL-2, and 1 PR and 1 SD in nine patients treated with DCs + peptides without IL-2. There were only two patients with SD in the group receiving DCs + autologous lysates and no IL-2. Median overall survival for all patients was very good at 18.5 months but this was most probably due to selection of a favourable group of patients for the study. There was no significant difference in survival between the groups by log rank analysis. Treatment was not associated with significant side effects. The quality and yield of the DCs in the preparations were generally good. We conclude that mature DC preparations may be superior to immature DC preparations for presentation of melanoma peptides and that IL-2 may increase clinical responses to the DCs plus peptides. However, in our view the low response rates do not justify the cost and complexity of this treatment approach. [ABSTRACT FROM AUTHOR]

Patients with thick, primary melanoma and regional lymph-node metastases are at moderate to high risk of recurrence and death, despite apparent complete surgical removal. Immune responses can be demonstrated against melanoma and this has prompted the conduct of a number of randomized trials of immunotherapy. Several trials have been completed and show minimal benefit in prolonging survival or recurrence from melanoma. Similarly, a large number of trials has been conducted to test the efficacy of α-2-interferon (IFN-α2) in therapy. Clear benefit in recurrence-free survival was shown in several trials, however there is a lack of convincing evidence of an effect on overall survival. Several trials of vaccine and IFN-α2 therapy are still in progress and their results are awaited with great interest. The use of highdose IFN-α2 therapy remains a contentious subject, however available evidence suggests the standard of care remains good surgical management. (Intern Med J 2003; 33:31 41) [ABSTRACT FROM AUTHOR]

A case of Sjögren's syndrome with the sicca complex is presented which was associated with persistently low or absent C4 levels, high levels of circulating immune complexes and abnormal reticuloendothelial clearance of damaged or IgG antibody sensitized autologous red blood cells (RBCs). Investigation of normal relatives of the patient revealed low C4 levels and abnormal reticuloendothelial clearance of damaged or sensitized RBCs, HLA, A, B, DR typing revealed a high incidence of the HLA B8, DR3 haplotype and of homozygous null alleles at the C4A locus in the family members. These results suggest that the C4 deficiency and the abnormal reticuloendothelial function in the patient was in part genetically determined and may have predisposed to the development of Sjögren's syndrome. These findings serve to emphasize the possible importance of abnormal macrophage function in the pathogenesis of Sjögren's syndrome and suggest that further investigation of these aspects may increase understanding of this disease. [ABSTRACT FROM AUTHOR]

A child with Fanconi's anaemia diagnosed at 7 years of age presented in adult life with lymphopenia, recurrent warts and Bowen's disease. The latter resulted in the development of multiple cutaneous squamous cell carcinomas which metastasized to the skeleton. Investigation of her immune function revealed selective defects in natural killer (NK) cell activity. Humoral immunity and several tests of cell-mediated responses were within normal or became normal after treatment with levamisole or transfer factor. Analysis of the defect in NK activity revealed that low levels could be induced in vitro by fibroblast interferon. Stimulation of blood lymphocytes from the patient with the interferon inducer poly (1)-poly (C) resulted in an increase in NK activity but incubation of her lymphocytes on tumour cells did not result in an increase in NK activity or the release of interferon. This contrasted with the marked increase in NK activity and interferon release observed when lymphocytes from normal controls were incubated on tumour cells. These findings suggested the absence of NK activity in this patient was secondary to a defect in interferon release from lymphocytes on exposure to tumour antigens. It is considered that these defects may have been an important predisposing factor in the development of malignancy in this patient and possibly other patients with Fanconi's anaemia. [ABSTRACT FROM AUTHOR]

The action of levamisole on immunoglobulin production was investigated in pokeweed mitogen-stimulated cultures of B and T cells. Immunoglobulin production was measured by nephelometric methods using specific antisera to IgA, IgG and IgM. Levamisole was shown to have no effect on B lymphocytes but pretreatment of T lymphocytes with levamisole resulted in an increase in immunoglobulin production which was maximal at 10-6 M. The latter increase appeared to be due to an effect on suppressor T cells in that pretreatment of T cells depleted of suppressor cells (by irradiation or removal of T cells with receptors with IgG) did not result in an increase in immunoglobulin production. Similar effects of levamisole were demonstrated against suppressor cells induced by concanavalin A in vitro and against spontaneous suppressor cell activity in vivo. The effect of levamisole and irradiation on suppressor cell activity against particular classes of immunoglobulin varied between individuals. Suppressor cell activity against IgA production alone was demonstrated in six of 17 subjects whereas in the remainder, suppressor cell activity was either not detected or inhibited production of all three immunoglobulin classes. The implications of this action of levamisole for its effects in vivo are unknown, but the results appear consistent with many of the observed effects of the drug. Selection of patients with diseases associated with high suppressor cell activity may lead to more effective use of the drug. [ABSTRACT FROM AUTHOR]

A number of previous studies have described antibodies in normal sera reactive to human leukaemia cells. In the course of studies on humoral immunity to acute myeloid leukaemia (AML) cells it was noticed that sera from normal subjects were cytotoxic in complement lysis and leucocyte dependent antibody (LDA) assays to blood leucocytes from patients with AML in remission. Investigation of these reactions in eleven patients with acute leukaemia in complete or partial remission revealed that reactivity occurred most frequently between sera from normal blood group O or B subjects and leucocytes from patients of blood group A (five patients). Leucocytes from blood group O patients were largely unreactive. Blood leucocytes from five of six patients in relapse did not react with normal sera. Subsequent studies revealed that the antigens were detected only on T lymphocytes. Reactivity could be removed by absorption on red cells of blood group A but not sheep or Ox red blood cells suggesting the antigens concerned were closely related to blood group A antigens. Some reactivity with antisera to the blood group H antigens was also evident in these studies. Gel filtration studies indicated that lymphocyte dependent antibody mediated cytotoxicity was mediated by IgG antibodies while complement dependent lysis was mainly mediated by IgM antibodies. The biological significance of these findings has yet to be determined hut these results suggest that reactivity with blood group antigens needs to he considered in in vitro cytotoxicity. [ABSTRACT FROM AUTHOR]

The underlying basis for hypogammaglobulinaemia in patients with chronic lymphatic leukaemia (CLL) was investigated by measurement of immunoglobulin produced in vitro in cultures of pokeweed mitogen-stimulated B and T lymphocytes. B and T cells were separated by sheep red blood cell rosette techniques and, by culture of these cells from CLL patients in various combinations with B or T cells from normal subjects, it was possible to measure independently the function of B lymphocytes and the helper or suppressor function of T lymphocytes. By these methods it was found that the B lymphocytes of six of eight patients failed to produce immunoglobulins in vitro. B lymphocytes from two patients appeared to produce immunoglobulins in vitro. T lymphocytes from five of the eight patients had low or undetectable helper T cell function and in six patients their T lymphocytes had excessive suppressor activity in comparison to T lymphocyte populations from normal subjects. Whether the primary abnormality in the CLL T cell populations was a deficiency of helper T cells or excess of suppressor T cells was uncertain from these studies. These results suggest that immunoglobulin production by B lymphocytes from most patients with CLL was abnormal but also that T cells from CLL patients may be abnormal in respect to their role in immunoglobulin production at an early stage of the disease. These findings may assist in understanding the pathogenesis of this disease and lead to new approaches in treatment. [ABSTRACT FROM AUTHOR]

The effector cells responsible for cytotoxic activity induced by phytohaemagglutinin, (PHA) pokeweed mitogen (PWM) and target cells complexed with lgG antibody has been investigated using cell separation techniques based on rosette Formation and separation through Hypaque-Ficoll mixtures. It was shown that PHA-induced cytotoxicity is predominantly a function of T cells and that Fc receptor-bearing cells are not involved to any major extent. Antibody-dependent killing is conversely a function of Fc receptor-bearing cells among which two subtypes can be distinguished. One of these has receptors for activated complement while the other bears receptors only and has no detectable receptors for complement. PWM appears to induce cytotoxicity in both T- and non-T-cell populations but the major cell type involved appears to be Fe receptor-bearing cells similar to those mediating antibody-dependent killing. It is concluded that PHA and antibody- dependent killing are the two most useful assays for discriminating between the cytotoxic activity of T and non-T cells in clinical studies. [ABSTRACT FROM AUTHOR]

Antibodies which are to induce the killing of allogeneic myeloblasts by normal lymphoid cells have been found in a high proportion of patients with acute myeloid leukaemia. The cytotoxic mechanism induced by this antibody activity is shown to be highly effective in terms of the number of myeloblasts which can be killed by a given number of lymphoid cells and the antibody concentration needed to induce killing. Reasons for the in vivo failure of this cytotoxic mechanism, assuming that antibodies occur against autologous myeloblasts, are suggested by studies in which the cytotoxic lymphoid population has been monitored serially. Some patients are shown to have almost undetectable levels of cytotoxic effector cell activity. A further reason for the failure of this mechanism related to 'blocking activity' in the serum is being investigated. Preliminary results suggest that assay of this antibody activity against myeloblasts may also be of value in following the response to immunotherapy and in providing early warning of relapse. It is suggested that the demonstration of antibody-dependent lymphocyte activity against acute myeloid leukaemic cells provides an additional insight into this disease which may have important implications in management and therapy of acute myeloid leukaemia. [ABSTRACT FROM AUTHOR]

Rat lymphoma cells sensitized with antibody and incubated with normal macrophages were shown to become resistant to damage from cytotoxic antibody and complement or cytotoxic lymphocytes. Both lymphoma specific antibody and normal macrophages were required to produce protection. The cytotoxic effect of lymphocytes or antibody with complement and the protective effect of antibody with macrophages was assessed by 51Cr release and by loss of capacity of iymphoma cells to transfer the disease to syngeneic rats. No cytotoxic effect could be attributed to macrophages from sensitized allogeneic rats. Inhibition of phagocytosis by Cytochalasin B did not destroy the capacity of macrophages to protect lymphoma cells. Sodium fluoride, however, did block the protective effect. It is envisaged that this protective phenomenon may be of importance in understanding some aspects of growth of tumours in vivo despite the presence of immune cytotoxic mechanisms. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to J. Hoyle and S. Yentis' review of block height assessment before caesarean section and the author's agreement that the lack of a gold standard can lead to confusion.

An abstract of the article "Defining competence for workplace based assessment & x2013; a pragmatic and thorough method," by P. Hersey and D. Laws is presented.

Chemotherapy, biological agents or combinations of both have had little impact on survival of patients with metastatic melanoma. Advances in understanding the genetic changes associated with the development of melanoma resulted in availability of promising new agents that inhibit specific proteins up-regulated in signal cell pathways or inhibit anti-apoptotic proteins. Sorafenib, a multikinase inhibitor of the RAF/RAS/MEK pathway, elesclomol (STA-4783) and oblimersen (G3139), an antisense oligonucleotide targeting anti-apoptotic BCl-2, are in phase III clinical studies in combination with chemotherapy. Agents targeting mutant B-Raf (RAF265 and PLX4032), MEK (PD0325901, AZD6244), heat-shock protein 90 (tanespimycin), mTOR (everolimus, deforolimus, temsirolimus) and VEGFR (axitinib) showed some promise in earlier stages of clinical development. Receptor tyrosine-kinase inhibitors (imatinib, dasatinib, sunitinib) may have a role in treatment of patients with melanoma harbouring c-Kit mutations. Although often studied as single agents with disappointing results, new targeted drugs should be more thoroughly evaluated in combination therapies. The future of rational use of new targeted agents also depends on successful application of analytical techniques enabling molecular profiling of patients and leading to selection of likely therapy responders. [ABSTRACT FROM PUBLISHER]

A response to a letter to the editor about the article "Oxygen wastage," that was published in the previous issue is presented.

A letter to the editor is presented in response to the article "Oxygen wastage from anaesthetic machines," that was published in the previous issue.

Lymphoid sub populations in the blood and rectal mucosa were studied in six patients with ulcerative colitis or Cohn's disease who had been treated for over three year with azathioprine. Serial assays were performed to observe the changes occurring up to 12 weeks after treatment with azathioprine was stooped. While the patients were on the drug tow lymphoid populations showed marked depression. These were the plasma cells of the rectal lamina procris, and blood lymphocytes with cytotoxic activity against antibody-sensitized tared cells ('k' cells). After stopping azathioprine, both population showed a rapid rise to reach near normal levels by 12 weeks, Most of the recovery occurred within 3-5 weeks. There was no significant change in circulating immunogolblin-staining cells which could be attributed to the drug. Nor was azathioprine shown to have any effect on the mitotic response of lymphocytes to phytohaemagglutinin. Three patients, however, gave very low or erratic responses to PHA, which may have been related either to their disease or to steroid therapy, These results are discussed in relation to the mode of action of purine analogues as immunosuppressive agents. [ABSTRACT FROM AUTHOR]

The evaluation of interferons in the treatment of malignant melanoma has been mainly in the treatment of advanced disease using interferons as the sole agent or in combination with other agents. Studies of the value of interferons as adjuvant therapy in high-risk primary melanoma patients are necessary, but no results have been published to date. Human interferon alpha produces low response rates as a sole agent, but in combination with cimetidine, a 30% response rate has been achieved. Recombinant alpha interferons give responses of 15%-20% in advanced melanomas, and combination with cimetidine does not enhance the response rate. Recombinant alpha interferons have been used in combination with other interferons, cimetidine, monoclonal antibodies, and cytotoxics, with either no or small improvement in response rates. DTIC with recombinant interferon alpha-2a has been shown to produce objective response rates of 26%, with low toxicity and maintenance of quality of life. A randomized trial with DTIC as the sole agent, compared with combination treatment, is being conducted to determine the significance of this finding. [ABSTRACT FROM AUTHOR]

Background Pembrolizumab demonstrated robust antitumor activity and safety in the phase Ib KEYNOTE-001 study (NCT01295827) of advanced melanoma. Five-year outcomes in all patients and treatment-naive patients are reported herein. Patients whose disease progressed following initial response and who received a second course of pembrolizumab were also analyzed. Patients and methods Patients aged ≥18 years with previously treated or treatment-naive advanced/metastatic melanoma received pembrolizumab 2 mg/kg every 3 weeks, 10 mg/kg every 3 weeks, or 10 mg/kg every 2 weeks until disease progression, intolerable toxicity, or patient/investigator decision to withdraw. Kaplan–Meier estimates of overall survival (OS) and progression-free survival (PFS) were calculated. Objective response rate and PFS were based on immune-related response criteria by investigator assessment (data cut-off, September 1, 2017). Results KEYNOTE-001 enrolled 655 patients with melanoma; median follow-up was 55 months. Estimated 5-year OS was 34% in all patients and 41% in treatment-naive patients; median OS was 23.8 months (95% CI, 20.2–30.4) and 38.6 months (95% CI, 27.2–not reached), respectively. Estimated 5-year PFS rates were 21% in all patients and 29% in treatment-naive patients; median PFS was 8.3 months (95% CI, 5.8–11.1) and 16.9 months (95% CI, 9.3–35.5), respectively. Median response duration was not reached; 73% of all responses and 82% of treatment-naive responses were ongoing at data cut-off; the longest response was ongoing at 66 months. Four patients [all with prior response of complete response (CR)] whose disease progressed during observation subsequently received second-course pembrolizumab. One patient each achieved CR and partial response (after data cut-off). Treatment-related AEs (TRAEs) occurred in 86% of patients and resulted in study discontinuation in 7.8%; 17% experienced grade 3/4 TRAE. Conclusions This 5-year analysis of KEYNOTE-001 represents the longest follow-up for pembrolizumab to date and confirms the durable antitumor activity and tolerability of pembrolizumab in advanced melanoma. Clinical Trial Registry ClinicalTrials.gov, NCT01295827. [ABSTRACT FROM AUTHOR]

Increased global protein synthesis and selective translation of mRNAs encoding proteins contributing to malignancy is common in cancer cells. This is often associated with elevated expression of eukaryotic translation initiation factor 4 (eIF4E), the rate-limiting factor of cap-dependent translation initiation. We report here that in human melanoma downregulation of miR-768-3p as a result of activation of the mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) pathway has an important role in the upregulation of eIF4E and enhancement in protein synthesis. Melanoma cells displayed increased nascent protein production and elevated eIF4E expression, which was associated with the downregulation of miR-768-3p that was predicted to target the 3′-untranslated region of the eIF4E mRNA. Overexpression of miR-768-3p led to the downregulation of the endogenous eIF4E protein, reduction in nascent protein synthesis and inhibition of cell survival and proliferation. These effects were efficiently reversed when eIF4E was co-overexpressed in melanoma cells. On the other hand, introduction of anti-miR-768-3p into melanocytes upregulated endogenous eIF4E protein expression and increased global protein synthesis. Downregulation of miR-768-3p appeared to be mediated by activation of the MEK/ERK pathway, in that treatment of BRAFV600E melanoma cells with the mutant BRAF inhibitor PLX4720 or exposure of either BRAFV600E or wild-type BRAF melanoma cells to the MEK inhibitor U0126 resulted in the upregulation of miR-768-3p and inhibition of nascent protein synthesis. This inhibition was partially blocked in cells cointroduced with anti-miR-768-3p. Significantly, miR-768-3p was similarly downregulated, which was inversely associated with the expression levels of eIF4E in fresh melanoma isolates. Taken together, these results identify downregulation of miR-768-3p and subsequent upregulation of eIF4E as an important mechanism in addition to phosphorylation of eIF4E responsible for MEK/ERK-mediated enhancement of protein synthesis in melanoma. [ABSTRACT FROM AUTHOR]

Background: Approximately 50% of melanomas harbor activating (V600) mutations in the serine-threonine protein kinase B-RAF (BRAF). The oral BRAF inhibitor vemurafenib (PLX4032) frequently produced tumor regressions in patients with BRAF V600-mutant metastatic melanoma in a phase 1 trial and improved overall survival in a phase 3 trial.Methods: We designed a multicenter phase 2 trial of vemurafenib in patients with previously treated BRAF V600-mutant metastatic melanoma to investigate the efficacy of vemurafenib with respect to overall response rate (percentage of treated patients with a tumor response), duration of response, and overall survival. The primary end point was the overall response rate as ascertained by the independent review committee; overall survival was a secondary end point.Results: A total of 132 patients had a median follow-up of 12.9 months (range, 0.6 to 20.1). The confirmed overall response rate was 53% (95% confidence interval [CI], 44 to 62; 6% with a complete response and 47% with a partial response), the median duration of response was 6.7 months (95% CI, 5.6 to 8.6), and the median progression-free survival was 6.8 months (95% CI, 5.6 to 8.1). Primary progression was observed in only 14% of patients. Some patients had a response after receiving vemurafenib for more than 6 months. The median overall survival was 15.9 months (95% CI, 11.6 to 18.3). The most common adverse events were grade 1 or 2 arthralgia, rash, photosensitivity, fatigue, and alopecia. Cutaneous squamous-cell carcinomas (the majority, keratoacanthoma type) were diagnosed in 26% of patients.Conclusions: Vemurafenib induces clinical responses in more than half of patients with previously treated BRAF V600-mutant metastatic melanoma. In this study with a long follow-up, the median overall survival was approximately 16 months. (Funded by Hoffmann-La Roche; ClinicalTrials.gov number, NCT00949702.). [ABSTRACT FROM AUTHOR]

Past studies have shown that upregulation of the anti-apoptotic Bcl-2 family protein Mcl-1 is a major adaptive mechanism of melanoma cells to endoplasmic reticulum (ER) stress, and has an important role in resistance of the cells to apoptosis. In this study, we show that the increase in transcription of Mcl-1 in melanoma cells triggered by pharmacological ER stress inducers is mediated by the transcription factor Ets-1. By incremental deletion analysis of the Mcl-1 promoter, we identified a DNA fragment containing an Ets-1 binding site that is transcriptionally responsive to ER stress. Mutations in the Ets-1 binding site or knockdown of Ets-1 inhibited the increase in Mcl-1, indicating that Ets-1 has a critical role in transcriptional upregulation of Mcl-1. Similar to Mcl-1, Ets-1 was transcriptionally upregulated by ER stress. This was mediated by the IRE1α/XBP-1 branch of the unfolded protein response, as upregulation of Ets-1 was inhibited in melanoma cell lines deficient in IRE1α or XBP-1 established by short hairpin RNA knockdown. Activation of the PI3k/Akt pathway downstream of XBP-1 was also involved, in that inhibition of the pathway blocked upregulation of Ets-1. Inhibition of Ets-1 enhanced ER stress-induced apoptosis in melanoma cell lines and in fresh melanoma isolates, recapitulating the effect of inhibition of Mcl-1. These results reveal a key mechanism by which Mcl-1 is transcriptionally upregulated in melanoma cells by ER stress, and identify Ets-1 as a potential target for inhibition to sensitize melanoma cells to apoptosis. [ABSTRACT FROM AUTHOR]

Past studies have identified a number of distinct mechanisms that contribute to the resistance of melanoma cells against apoptosis induced by TNF-related apoptosis-inducing ligand (TRAIL). In this report we show that cystatin B is another endogenous inhibitor of TRAIL-induced apoptosis. Cystatin B-deficient melanoma cell lines established by shRNA knockdown displayed increased apoptosis that was associated with enhanced activation of caspase-8 induced by TRAIL. This was not related to the inhibitory effect of cystatin B on the lysosomal cysteine proteases, cathepsin B and L, as they did not have a role in TRAIL-induced apoptosis in most melanoma cell lines even when cystatin B was inhibited. Instead, sensitization of melanoma cells to TRAIL-induced apoptosis by inhibition of cystatin B appeared associated with decreased stability of FLIPL as the levels of FLIPL were reduced because of shortened half-life time in melanoma cells deficient in cystatin B. In contrast, over-expression of cystatin B increased the levels of FLIPL, decreased the amount of the E3 ligase Itch associated with FLIPL, and reduced FLIPL ubiquitination. Inhibition of Itch by siRNA restored the levels of FLIPL and blocked sensitization to TRAIL-induced apoptosis associated with deficiency in cystatin B. Taken together, these results indicate that cystatin B regulates Itch-mediated degradation of FLIPL and thereby TRAIL-induced apoptosis in melanoma cells. [ABSTRACT FROM AUTHOR]

We evaluated the pharmacodynamic effects of the O(6)-methylguanine-DNA methyltransferase (MGMT) inactivator lomeguatrib (LM) on patients with melanoma in two clinical trials. Patients received temozolomide (TMZ) for 5 days either alone or with LM for 5, 10 or 14 days. Peripheral blood mononuclear cells (PBMCs) were isolated before treatment and during cycle 1. Where available, tumour biopsies were obtained after the last drug dose in cycle 1. Samples were assayed for MGMT activity, total MGMT protein, and O(6)-methylguanine (O(6)-meG) and N7-methylguanine levels in DNA. MGMT was completely inactivated in PBMC from patients receiving LM, but detectable in those on TMZ alone. Tumours biopsied on the last day of treatment showed complete inactivation of MGMT but there was recovery of activity in tumours sampled later. Significantly more O(6)-meG was present in the PBMC DNA of LM/TMZ patients than those on TMZ alone. LM/TMZ leads to greater MGMT inactivation, and higher levels of O(6)-meG than TMZ alone. Early recovery of MGMT activity in tumours suggested that more protracted dosing with LM is required. Extended dosing of LM completely inactivated PBMC MGMT, and resulted in persistent levels of O(6)-meG in PBMC DNA during treatment. [ABSTRACT FROM AUTHOR]

Temozolomide (TMZ), a DNA alkylating agent used in the treatment of melanoma, is believed to mediate its effect by addition of a methyl group to the O(6) position of guanine in DNA. Resistance to the agent may be in part due to the activity of O(6)-methylguanine-DNA methyl transferase (MGMT). In the present study, we show that sensitivity of melanoma cells to TMZ was dependent on their p53 status and levels of MGMT. Analysis of the mechanisms underlying reduced viability showed no evidence for induction of apoptosis even though marked levels of apoptosis was seen in TK6 lymphoma cells. Sensitivity of melanoma cells was associated with p53-dependent G2/M cell cycle arrest and induction of senescence. To verify the role of p53, the assays were repeated in presence of pifithrin-alpha, an inhibitor of p53. This resulted in increased viability of melanoma cells with wild-type p53 and reversed G2/M cell cycle arrest. Paradoxically, apoptosis was increased in melanoma but decreased as expected in TK6 lymphoma cells. These results are consistent with the view that TMZ is relatively ineffective against melanoma due to defective apoptotic signalling resulting from activation of p53. The nature of the defects in apoptotic signalling remains to be explored. [ABSTRACT FROM AUTHOR]

Background: Several studies suggest that melanoma may be resistant to treatment because of resistance to apoptosis and that this may be the result of activation of the extracellular signal regulated kinase (ERK1/2) pathway. Aims: To test this hypothesis by examining the expression of ERK1/2 and its activated form in histological sections of melanoma and its relation to known prognostic features of the disease. Materials/Methods: Immunohistochemistry with antibodies to ERK1/2 and phosphorylated ERK (p-ERK) was performed on formalin fixed sections from 42 primary melanomas, 38 metastases, and 20 naevi. Fourteen of the primary melanomas were in the radial and 28 in the vertical growth phase. Results: ERK1/2 was widely expressed (100%) in all the (pigmented) lesions studied. p-ERK1/2 expression was much lower in compound (32.4%) and dysplastic (54.5%) naevi than in primary melanoma (nodular 78.8%, superficial spreading 67%) and subcutaneous metastases (76.3%). p-ERK expression was much lower in lymph node metastases (48.5%), suggesting that the microenvironment may influence the activation of ERK. There was a (non-significant) trend for p-ERK expression to be higher in thick (>1.0 mm) versus thin (⩽ 1.0 mm) melanoma (p = 0.23). There was a trend for overall survival to be related to p-ERK expression in patients with melanoma over 1 mm in thickness. Conclusions: Expression of activated ERK1/2 in melanocytic lesions appears to be related to malignant potential so that activation of ERK1/2 may be important in melanoma progression. These results provide important histological support for the proposal that inhibition of this signalling pathway may be useful in treatment of melanoma. [ABSTRACT FROM AUTHOR]

We have previously shown that tumour cells may release soluble factors which inhibit the division of a variety of cells. These factors had marked immunosuppressive activity in vitro as shown by their ability to Inhibit lymphocyte mitogenic responses to lectins. allogeneic lymphocytes and pokeweed mitogen-induced immunoglobulin production. It was postulated that these factors may play an important role in determining the outcome of tumour host interactions in humans and be the source of immunosuppressive factors in the circulation of patients with cancer. In the present study, characterization of these mitogenic inhibitory factors released into the supernatants of cultured tumour cells was carried out by a number of sequential separation procedures involving affinity chromatography on wheat-germ lectin (WGL). gel filtration on PL-agarose and electrophoresis in polyacrylamide gels in the presence of sodium dodecyl sulphate (PAGE-SDS). The factors were identified throughout the separation procedure using inhibition of phytohaemagglutinin (PHA) stimulation of normal lymphocytes as an index of inhibitory function. By these techniques the inhibitory activity was shown to be associated with glycoproteins containing N-acetyl-β-D-glucosamine (NAcGlu) and having molecular weights (mol. wt) of approximately 140.000 and over 200,000 daltons. A further small mol. wt peak of 70,000 daltons was observed on PAGE-SDS. pi values of the fractions were 7.4 and 4.2. The activity was destroyed by heating, low pH and repeated freeze-thawing but was resistant to proteolytic enzymes, deoxyribonuclease, ribonuclease and neuraminidase. The active fractions were not associated with proteolytic activity and the inhibition of mitogenic responses was irreversible in nature. These results form the basis of studies to detect this factor in biological fluids and further evaluate its role in the tumour host relationship. [ABSTRACT FROM AUTHOR]

A number of previous reports have described the presence of factors which inhibit the response of lymphoid cells to phytohaemagglutinin. The present study describes an inhibitor of cell division synthesized and released directly from cultured tumour cells which appears to have similar immunosuppressive effects in vitro. This factor(s) was detected in a wide variety of cultured tumour cells and some cultures of normal foetal tissue. It inhibited the mitogenic response of lymphocytes to PHA and also the spontaneous cell division of a variety of cultured cells including the cells producing the factor. Pulse cytophotometry showed that cells were inhibited in the G1 phase. Production of the factor increased with time and was related to the number of cells in culture. Its synthesis was inhibited by cycloheximide. DNA and RNA synthesis was not required for its production. The factor appeared to have a high degree of biological activity m terms of the number of cultured cells required for production and in regard to the number of cells inhibited. The biological significance of this factor in vivo is unknown but in vitro it was shown to inhibit immunoglobulin and mitogen-induced responses which suggests it may play an important role in suppression of the immune response against tumour cells in the host. [ABSTRACT FROM AUTHOR]

Blood lymphocytes and rectal plasma cells have been studied in patients with ulcerative colitis taking part in a douhle-blind trial of treatment with azathioprine. Treatment for 1 year resulted in a modest fall in blood lymphocyte count, with little change in neutrophils or platelets. There was no major change in the proportions of circulating T and B lymphocytes, suggesting that the number of such cells per millilitre of blood fell in proportion to the change in lymphocyte count. The number of plasma cells in the rectal lamina propria was reduced to a mean less than half that of the control patient group. Blood K-cell cytotoxic activity fell at least 25-foId after 1 year's treatment. PHA-induced cytotoxicity was also reduced, but less consistently. Reduced K-cell activity is interpreted as reflecting depletion of effector cells from the circulation. The fall in lymphocyte count, K-cell activity and gut plasma cells was slow, indicating continuous inhibition of lymphopoiesis or differentiation throughout the trial period. Thus, azathioprine has some immunosuppressive effects which develop only after prolonged treatment. The clinical results of the trial did not show a major beneficial effect of azathioprine in the treatment of ulcerative colitis, nor were there clear correlations between the results of lymphocyte assays and clinical response in individual patients. [ABSTRACT FROM AUTHOR]

This report investigates functions and number of different lymphocyte types in patients with testicular and ovarian tumours before, during and following therapeutic irradiation. Irradiation causes loss of T cells, B cells and K cells at similar rates. The long term depletion of T cells, which is well recorded, is due to delayed and incomplete repopulation of a substantial proportion of this cell type. B cells and K cells, however, return to levels very close to normal by 6 and 3 months respectively after irradiation. Long-term depletion of T cells occurs even when the thymus is not irradiated. [ABSTRACT FROM AUTHOR]

Background: No studies measure preference-based utilities in advanced melanoma that capture both intended clinical response and unintended toxicities associated with treatment.Methods: Using standard gamble, utilities were elicited from 140 respondents in the United Kingdom and Australia for 13 health states.Results: Preferences decreased with reduced treatment responsiveness and with increasing toxicity.Conclusions: These general population utilities can be incorporated into treatment-specific cost-effectiveness evaluations. [ABSTRACT FROM AUTHOR]

Presents a letter to the editor "Cell Death and Differentiation" journal concerning a study which indicated that the absence of caspase-9 coactivator Apaf-1 or the associated caspase-9 did not affect either apoptosis or drug sensitivity in a lymphoid tumor model or in primary lymphocytes, raising doubts that Apaf-1 is crucial to apoptosis.

Reports on a case of vaccinia necrosis in a 66-year-old man presented with a large erythemathus eruption in his right upper arm. Overview of the development of the complication from smallpox vaccination with vaccinia; Attribution of the complication to chronic lymphocytic leukemia in the patient; Manifestations of the disease and other complications; Patient characteristics and medical history; Treatment.

Background Pembrolizumab is a potent humanised monoclonal antibody against PD-1 that has shown efficacy and safety in patients with advanced solid tumours and haematological malignancies. Methods KEYNOTE-001 (NCT01295827) was a multicohort phase 1 study that included 411 patients with advanced melanoma, including 221 who previously received ipilimumab (IPI-T) and 190 who were ipilimumab naive (IPI-N). Patients received pembrolizumab at 10 mg/kg every 3 weeks (Q3W), 2 mg/kg Q3W, or 10 mg/kg Q2W. Response was assessed every 12 weeks per RECIST v1.1 by independent central review and per immune-related response criteria (irRC) by the investigator. Findings As of the April 18 2014, median follow-up duration for all patients was 18 months (range 12–28). The 360 patients with measurable disease per central review at baseline had objective response/disease control rates per RECIST of 34%/54% (29%/54% in IPI-T patients, 39%/55% in IPI-N patients). By irRC, objective response/disease control rates were 39%/64% (34%/65% in IPI-T patients, 45%/64% in IPI-N patients). 57 patients who had progressive disease by RECIST had non-progressive disease by irRC. Responses were durable, with 81% ongoing at analysis (median response duration not reached; range, 6+ to 98+ weeks). Pembrolizumab showed antitumour benefit at all doses and schedules regardless of ECOG performance status, previous IPI, or LDH levels. Per RECIST, 6-month PFS was 45% (42% for IPI-T, 48% for IPI-N). Median overall survival was 25.9 months, with a 69% 1-year overall survival (65% for IPI-T, 74% for IPI-N). Pembrolizumab was safe and well tolerated, with 14% of all patients experiencing drug-related grade 3/4 adverse events (15% IPI-N, 14% IPI-T) and only 5% discontinuing pembrolizumab because of a drug-related adverse events (6% IPI-N, 5% IPI-T). There were no treatment-related deaths. Interpretation Pembrolizumab provides a favourable benefit-risk profile in both IPI-T and IPI-N patients, suggesting it could be a promising treatment option for all patients with advanced melanoma. [ABSTRACT FROM AUTHOR]

Immunotherapy of metastatic melanoma consists of various approaches leading to specific or non-specific immunomodulation. The use of FDA-approved interleukin (IL)-2 alone, in combination with interferon α, and/or with various chemotherapeutic agents (biochemotherapy) is associated with significant toxicity and poor efficacy that does not improve overall survival of 96% of patients. Many studies with allogeneic and autologous vaccines have demonstrated no clinical benefit, and some randomised trials even showed a detrimental effect in the vaccine arm. The ongoing effort to develop melanoma vaccines based on dendritic cells and peptides is driven by advances in understanding antigen presentation and processing, and by new techniques of vaccine preparation, stabilisation and delivery. Several agents that have shown promising activity in metastatic melanoma including IL-21 and monoclonal antibodies targeting cytotoxic T lymphocyte-associated antigen 4 (anti-CTLA-4) or CD137 are discussed. Recent advances of intratumour gene transfer technologies and adoptive immunotherapy, which represents a promising although technically challenging direction, are also discussed. [ABSTRACT FROM PUBLISHER]

Biomarkers are tumour- or host-related factors that correlate with tumour biological behaviour and patient prognosis. High-throughput analytical techniques—DNA and RNA microarrays—have identified numerous possible biomarkers, but their relevance to melanoma progression, clinical outcome and the selection of optimal treatment strategies still needs to be established. The review discusses a possible molecular basis for predictive tissue biomarkers such as melanoma thickness, ulceration and mitotic activity, and provides a list of promising new biomarkers identified from tissue microarrays that needs confirmation by independent, prospectively collected clinical data sets. In addition, common predictive serum biomarkers—lactate dehydrogenase, S100B and melanoma-inhibiting activity—as well as selected investigational serum biomarkers such as TA90IC and YKL-40 are also reviewed. A more accurate, therapeutically predictive classification of human melanomas and selection of patient populations that would profit from therapeutic interventions are among the major challenges expected to be addressed in the future. [ABSTRACT FROM PUBLISHER]

The lack of effective drugs in stage IV melanoma has impacted the effectiveness of adjuvant therapies in stage II/III disease. To date, chemotherapy, immunostimulants and vaccines have been used with minimal success. Interferon (IFN) has shown an effect on relapse-free survival (RFS) in several clinical trials; however, without a clinically significant effect on overall survival (OS). A recently conducted meta-analysis demonstrated prolongation of disease-free survival (DFS) in 7% and OS benefit in 3% of IFN-treated patients when compared with observation-only patients. There were no clear differences for the dose and duration of treatment observed. Observation is still an appropriate control arm in adjuvant clinical trials. Regional differences exist in Europe in the adjuvant use of IFN. In Northwest Europe, IFN is infrequently prescribed. In Central and Mediterranean Europe, dermatologists commonly prescribe low-dose IFN therapy for AJCC stage II and III disease. High-dose IFN regimens are not commonly used. The population of patients that may benefit from IFN needs to be further characterised, potentially by finding biomarkers that can predict response. Such studies are ongoing. [ABSTRACT FROM PUBLISHER]