Comparative Benefit-Risk Assessment for Lidocaine 700 mg Medicated Plaster and Pregabalin in Peripheral Neuropathic Pain Following a Structured Framework Approach.

INTRODUCTION: Peripheral neuropathic pain (PNP) is difficult to treat. Several oral drugs are recommended as first-line treatments. Nevertheless, many patients cannot obtain sufficient pain relief or do not tolerate systemically active treatments. Topical treatments, with a lower risk of systemic side effects such as lidocaine 700 mg medicated plaster, are also recommended in treatment guidelines. This analysis compares the benefit-risk balance of topical 700 mg lidocaine medicated plaster with the benefit-risk balance of oral pregabalin administration for the treatment of PNP following current recommendations on benefit-risk assessment (BRA) methodology. METHODS: The Benefit-Risk Action Team (BRAT) framework was used as structured approach. Selection of key benefits and risks was supported by a patient survey. Published randomized controlled clinical trials were the main source to identify data related to key benefits and risks. The outcome of randomized clinical trials was compared with real-world evidence (RWE) data for consistency. RESULTS: Identified key benefits were pain reduction and improvement in quality of life. Key risks identified were application site reactions, dizziness, confusion, weight gain, peripheral edema, and blurred vision. Overall, there was similarity in key benefits between the comparators; however, a clear advantage regarding key risks in favor of lidocaine 700 mg medicated plaster was observed. This observation was consistent across data from a direct comparison trial, randomized placebo-controlled trials, as well as data from RWE studies. The low number of randomized controlled trials for lidocaine 700 mg medicated plaster was the main limitation. CONCLUSION: Guided by the opinion of patients regarding key benefits and risks deemed important for treatments of peripheral neuropathic pain, our analysis showed that lidocaine 700 mg medicated plaster has a more favorable benefit-risk balance compared to pregabalin (300 and 600 mg daily).

High prevalence of Y-box protein-1/p18 fragment in plasma of patients with malignancies of different origin.

BACKGROUND: Expression of the cold shock protein Y-box protein 1 (YB-1) is associated with deleterious outcome in various malignant diseases. Our group recently showed that the detection of an 18 kDa YB-1 fragment (YB-1/p18) in human plasma identifies patients with malignant diseases. We now tested the prevalence, clinical, and diagnostic value of YB-1/p18 detection in common tumors. METHODS: A newly established monoclonal YB-1 antibody was used to detect YB-1/p18 by immunoblotting in plasma samples from 151 unselected tumor patients, alongside established tumor markers and various diagnostic measures, during evaluation for a cancerous disease and in follow-up studies after therapeutic interventions. RESULTS: Circulating YB-1/p18 was detected in 78% of patients having a tumor disease. YB-1/p18 positivity was highly prevalent in all examined malignancies, including lung cancer (32/37; 87%), breast cancer (7/10; 70%), cancer of unknown primary (CUP; 5/5, 100%) or hematological malignancies (42/62; 68%). Positivity for YB-1/p18 was independent of other routine laboratory parameters, tumor stage, or histology. In comparison to 13 established tumor markers (cancer antigens 15-3, 19-9, 72-4, and 125; carcinoembryonic antigen; cytokeratin fragments 21-1; neuron-specific enolase; alpha-fetoprotein; beta-2-microglobulin; squamous cell carcinoma antigen; thymidine kinase; tissue polypeptide antigen; pro-gastrin-releasing peptide), YB-1/p18 detection within serum samples was the most sensitive general parameter identifying malignant disorders. YB-1/p18 concentrations altered during therapeutic interventions, but did not predict prognosis. CONCLUSIONS: Plasma YB-1/p18 detection has a high specific prevalence in malignancies, thereby providing a novel tool for cancer screening independent of the tumor origin.

Epigenetic dysregulation of secreted frizzled-related proteins in myeloproliferative neoplasms complements the JAK2V617F-mutation.

BACKGROUND: Secreted frizzled-related proteins (SFRPs) are antagonists of the Wnt signaling pathway, which plays a central role in stem cell maintenance and differentiation of stem cells and hematopoietic progenitors. Epigenetic downregulation of SFRPs by promoter hypermethylation has been described to be involved in the pathogenesis of hematopoietic malignancies. There is an association between aberrant Wnt signaling and the established cancer stem cell concept. In contrast to BCR-ABL1-positive chronic myeloid leukemia CML, BCR-ABL1-negative myeloproliferative neoplasms (Ph-MPN) are characterized by the frequent occurrence of an autoactivating mutation in the JAK2 tyrosine kinase (JAK2V617F) or other mutations in the JAK-STAT pathway. However, pathogenetic mechanisms of JAK2 mutated or unmutated Ph-MPN remain not completely understood. We determined the promoter methylation status of SFRP-1, -2, -4, and -5 in 57 MPN patient samples by methylation-specific polymerase chain reaction (PCR) (MSP). JAK2V617F was assessed by allele-specific PCR. RESULTS: Aberrant methylation among primary MPN samples was 4% for SFRP-1, 25% for SFRP-2, 2% for SFRP-4, and 0% for SFRP-5. Hypermethylation of SFRP-2, which was the most frequently hypermethylated gene in our study, could not be correlated to any specific MPN subtype. However, we detected a significant correlation between SFRP-2 methylation and presence of a JAK2V617F mutation (P = 0.008). None of the 10 CML samples showed any SFRP-methylation. CONCLUSIONS: Our data indicate that epigenetic dysregulation of the Wnt signaling pathway is a common event in MPN with aberrant methylation of at least one SFRP being detected in 25% of the primary patient samples and in 30% if only accounting for Ph-MPN. A significant correlation between SFRP-2 methylation and presence of JAK2V617F in our data supports the hypothesis that epigenetic dysregulation may be a complementary mechanism to genetic aberrations. Aberrant methylation of crucial stem cell maintenance genes seems to contribute to disease pathogenesis in Ph-MPN.

A systematic comparison of quantitative high-resolution DNA methylation analysis and methylation-specific PCR.

Assessment of DNA methylation has become a critical factor for the identification, development and application of methylation based biomarkers. Here we describe a systematic comparison of a quantitative high-resolution mass spectrometry-based approach (MassARRAY), pyrosequencing and the broadly used methylation-specific PCR (MSP) technique analyzing clinically relevant epigenetically silenced genes in acute myeloid leukemia (AML). By MassARRAY and pyrosequencing, we identified significant DNA methylation differences at the ID4 gene promoter and in the 5' region of members of the SFRP gene family in 62 AML patients compared with healthy controls. We found a good correlation between data obtained by MassARRAY and pyrosequencing (correlation coefficient R(2) = 0.88). MSP-based assessment of the identical samples showed less pronounced differences between AML patients and controls. By direct comparison of MSP-derived and MassARRAY-based methylation data as well as pyrosequencing, we could determine overestimation of DNA methylation data by MSP. We found sequence-context dependent highly variable cut-off values of quantitative DNA methylation values serving as discriminator for the two MSP methylation categories. Moreover, good agreements between quantitative methods and MSP could not be achieved for all investigated loci. Significant correlation of the quantitative assessment but not of MSP-derived methylation data with clinically important characteristics in our patient cohort demonstrated clinical relevance of quantitative DNA methylation assessment. Taken together, while MSP is still the most commonly applied technique for DNA methylation assessment, our data highlight advantages of quantitative approaches for precise characterization and reliable biomarker use of aberrant DNA methylation in primary patient samples, particularly.

Differential role of gp130-dependent STAT and Ras signalling for haematopoiesis following bone-marrow transplantation.

INTRODUCTION: Bone marrow transplantation (BMT) is a complex process regulated by different cytokines and growth factors. The pleiotropic cytokine IL-6 (Interleukin-6) and related cytokines of the same family acting on the common signal transducer gp130 are known to play a key role in bone marrow (BM) engraftment. In contrast, the exact signalling events that control IL-6/gp130-driven haematopoietic stem cell development during BMT remain unresolved. METHODS: Conditional gp130 knockout and knockin mice were used to delete gp130 expression (gp130(ΔMx)), or to selectively disrupt gp130-dependent Ras (gp130(ΔMxRas)) or STAT signalling (gp130(ΔMxSTAT)) in BM cells. BM derived from the respective strains was transplanted into irradiated wildtype hosts and repopulation of various haematopoietic lineages was monitored by flow cytometry. RESULTS: BM derived from gp130 deficient donor mice (gp130(ΔMx)) displayed a delayed engraftment, as evidenced by reduced total white blood cells (WBC), marked thrombocytopenia and anaemia in the early phase after BMT. Lineage analysis unravelled a restricted development of CD4(+) and CD8(+) T-cells, CD19(+) B-cells and CD11b(+) myeloid cells after transplantation of gp130-deficient BM grafts. To further delineate the two major gp130-induced signalling cascades, Ras-MAPK and STAT1/3-signalling respectively, we used gp130(ΔMxRas) and gp130(ΔMxSTAT) donor BM. BMT of gp130(ΔMxSTAT) cells significantly impaired engraftment of CD4(+), CD8(+), CD19(+) and CD11b(+) cells, whereas gp130(ΔMxRas) BM displayed a selective impairment in early thrombopoiesis. Importantly, gp130-STAT1/3 signalling deficiency in BM grafts severely impaired survival of transplanted mice, thus demonstrating a pivotal role for this pathway in BM graft survival and function. CONCLUSION: Our data unravel a vital function of IL-6/gp130-STAT1/3 signals for BM engraftment and haematopoiesis, as well as for host survival after transplantation. STAT1/3 and ras-dependent pathways thereby exert distinct functions on individual bone-marrow-lineages.

A DNA methylation fingerprint of 1628 human samples.

Most of the studies characterizing DNA methylation patterns have been restricted to particular genomic loci in a limited number of human samples and pathological conditions. Herein, we present a compromise between an extremely comprehensive study of a human sample population with an intermediate level of resolution of CpGs at the genomic level. We obtained a DNA methylation fingerprint of 1628 human samples in which we interrogated 1505 CpG sites. The DNA methylation patterns revealed show this epigenetic mark to be critical in tissue-type definition and stemness, particularly around transcription start sites that are not within a CpG island. For disease, the generated DNA methylation fingerprints show that, during tumorigenesis, human cancer cells underwent a progressive gain of promoter CpG-island hypermethylation and a loss of CpG methylation in non-CpG-island promoters. Although transformed cells are those in which DNA methylation disruption is more obvious, we observed that other common human diseases, such as neurological and autoimmune disorders, had their own distinct DNA methylation profiles. Most importantly, we provide proof of principle that the DNA methylation fingerprints obtained might be useful for translational purposes by showing that we are able to identify the tumor type origin of cancers of unknown primary origin (CUPs). Thus, the DNA methylation patterns identified across the largest spectrum of samples, tissues, and diseases reported to date constitute a baseline for developing higher-resolution DNA methylation maps and provide important clues concerning the contribution of CpG methylation to tissue identity and its changes in the most prevalent human diseases.

Quantitative analyses of DAPK1 methylation in AML and MDS.

Aberrant DNA methylation and concomitant transcriptional silencing of death-associated protein kinase 1 (DAPK1) have been demonstrated to be key pathogenic events in chronic lymphocytic leukemia (CLL). In acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS), however, the presence of elevated DNA methylation levels has been a matter of continued controversy. Several studies demonstrated highly variable frequencies of DAPK1 promoter methylation by the use of methylation-specific PCR (MSP). By quantitative high-resolution assessment, we demonstrate that aberrant DNA methylation is an extremely rare event in this region. We observed elevated levels just in one out of 246 (0.4%) AML patients, all 42 MDS patients were unmethylated. In conclusion, we present a refined DAPK1 methylation analysis in a large representative patient cohort of AML and MDS patients proofing almost complete absence of elevated DNA methylation. Our results highlight the importance of quantitative measurements for translational research questions on primary patient specimens, particularly.

A multicenter phase II trial of decitabine as first-line treatment for older patients with acute myeloid leukemia judged unfit for induction chemotherapy.

BACKGROUND: The treatment of acute myeloid leukemia of older, medically non-fit patients still poses a highly unmet clinical need, and only few large, prospective studies have been performed in this setting. Given the established activity of hypomethylating agents such as 5-aza-2'-deoxycytidine (decitabine) in myelodysplastic syndromes and acute myeloid leukemia with 20-30% bone marrow blasts, we investigated whether this drug is also active in patients with more than 30% blasts. DESIGN AND METHODS: To evaluate the efficacy and toxicity of decitabine in patients over 60 years old with untreated acute myeloid leukemia ineligible for induction chemotherapy, 227 patients (median age, 72 years), many with comorbidities, adverse cytogenetics and/or preceding myelodysplastic syndrome were treated with this hypomethylating agent. During the initial decitabine treatment (135 mg/m(2) total dose infused intravenously over 72 hours every 6 weeks), a median of two cycles was administered (range, 1-4). All-trans retinoic acid was administered to 100 patients during course 2. Fifty-two patients who completed four cycles of treatment subsequently received a median of five maintenance courses (range, 1-19) with a lower dose of decitabine (20 mg/m(2)) infused over 1 hour on 3 consecutive days every 4-6 weeks. RESULTS: The complete and partial remission rate was 26%, 95% CI (20%, 32%), and an antileukemic effect was noted in 26% of patients. Response rates did not differ between patients with or without adverse cytogenetics; patients with monosomal karyotypes also responded. The median overall survival from the start of decitabine treatment was 5.5 months (range, 0-57.5+) and the 1-year survival rate was 28%, 95%CI (22%,34%). Toxicities were predominantly hematologic. CONCLUSIONS: Decitabine is well tolerated by older, medically non-fit patients with acute myeloid leukemia; myelosuppression is the major toxicity. The response rate and overall survival were not adversely influenced by poor-risk cytogenetics or myelodysplastic syndrome. Because of these encouraging results, randomized studies evaluating single-agent decitabine versus conventional treatment are warranted. The study is registered with the German Clinical Trials Registry, number DRKS00000069.

Methylation-associated dysregulation of the suppressor of cytokine signaling-3 gene in multiple myeloma.

The family of suppressor of cytokine signaling (SOCS) proteins negatively regulates cytokine signaling in different cellular pathways including interleukin-6 (IL-6). Since IL-6 plays an essential role in regulating growth and survival of multiple myeloma (MM) cells, methylation-associated dysregulation of SOCS3 may contribute to the malignant phenotype of MM cells. We used methylation-specific PCR (MSP) to assess the methylation status of the SOCS3 CpG island in five MM cell lines and 70 patient samples. Additional bisulfite sequencing and RNA expression analysis using reverse transcriptase polymerase chain reaction was performed in two cell lines. We identified aberrant SOCS3 methylation in 3/5 MM cell lines. Methylation of SOCS3 in cell lines was associated with transcriptional downregulation. Treatment of OPM-2 cells, which carry a methylated SOCS3 gene, with the demethylating agent 5-aza-2'-deoxycytidine restored SOCS3 expression in association with partial demethylation. In patient samples with malignant plasma cell disorders, SOCS3 was methylated in 5/70 (7.1 %) cases, while there was no aberrant SOCS3 methylation in normal peripheral blood and non-malignant bone marrow cells. We found an association of SOCS3 methylation with extramedullary manifestations (p = 0.03), plasma cell leukemia (p = 0.003), elevated LDH (p = 0.001), increased creatinine ( p = 0.01) and remarkably shortened survival (6.9 vs. 56.1 months, HR 5.9, p = 0.0007). Our findings reveal a novel epigenetic event possibly implicated in the pathogenesis of MM and representing a potential prognostic biomarker. Epigenetic dysregulation of the SOCS3 gene may interfere with the cellular response to the complex cytokine network thus supporting survival and expansion of MM cells.

Array-based DNA methylation profiling in acute myeloid leukaemia.

Methylation in the promoter region of many genes is involved in regulating gene expression patterns. Using the Illumina GoldenGate© methylation assay, we examined the methylation status of 1505 CpG-sites from 807 genes in 32 samples from patients with acute myeloid leukaemia (AML) at diagnosis, nine at relapse and 15 normal controls and performed additional pyrosequencing and semiquantitative methylation specific polymerase chain reaction (MSP) of the GNMT promoter in 113 diagnostic AML samples. We found a gain of overall methylation in AML samples with a further increase at relapse. Regional hypermethylation as assessed by array analysis could be confirmed by both MSP and pyrosequencing. Additionally, large-scale methylation analysis identified interesting candidate genes. Cluster analysis indicated that cytogenetic subgroups seemed to be characterized by additional distinct epigenetic modifications and that basic DNA methylation patterns remain at relapse. Therefore, promoter hypermethylation is a frequent event in AML and is accentuated at relapse. Array-based methylation analysis determined distinct methylation profiles for non-malignant controls and AML samples with specific chromosomal aberrations and can identify target genes for further evaluation.

Serum after autologous transplantation stimulates proliferation and expansion of human hematopoietic progenitor cells.

Regeneration after hematopoietic stem cell transplantation (HSCT) depends on enormous activation of the stem cell pool. So far, it is hardly understood how these cells are recruited into proliferation and self-renewal. In this study, we have addressed the question if systemically released factors are involved in activation of hematopoietic stem and progenitor cells (HPC) after autologous HSCT. Serum was taken from patients before chemotherapy, during neutropenia and after hematopoietic recovery. Subsequently, it was used as supplement for in vitro culture of CD34(+) cord blood HPC. Serum taken under hematopoietic stress (4 to 11 days after HSCT) significantly enhanced proliferation, maintained primitive immunophenotype (CD34(+), CD133(+), CD45(-)) for more cell divisions and increased colony forming units (CFU) as well as the number of cobblestone area-forming cells (CAFC). The stimulatory effect decays to normal levels after hematopoietic recovery (more than 2 weeks after HSCT). Chemokine profiling revealed a decline of several growth-factors during neutropenia, including platelet-derived growth factors PDGF-AA, PDGF-AB and PDGF-BB, whereas expression of monocyte chemotactic protein-1 (MCP-1) increased. These results demonstrate that systemically released factors play an important role for stimulation of hematopoietic regeneration after autologous HSCT. This feedback mechanism opens new perspectives for in vivo stimulation of the stem cell pool.

Aberrant DNA hypermethylation of the ITIH5 tumor suppressor gene in acute myeloid leukemia.

Epigenetic mechanisms such as DNA hypermethylation and modifications of histone amino acids are known to play an important role in the control of gene expression both in normal human development and tumorigenesis. Hypermethylation of CpG islands within promoter regions of tumor suppressor genes is associated with transcriptional inactivation and represents, in addition to genetic aberrations, an important mechanism of gene silencing in the pathogenesis of human cancer. Inter-α-trypsine inhibitors (ITIs) are a family of serine protease inhibitors consisting of one light chain (bikunin) and two heavy chains (ITI heavy chains, ITIHs). ITIHs stabilize the extracellular matrix (ECM) by interacting with hyaluronic acid, which is a major ECM component. Hypermethylation in the upstream region of the promoter-associated CpG island of ITIH5, the most recently described member of the ITIH family, has been previously detected in breast cancer and was associated with an adverse outcome. In this study, we determined the DNA methylation status of the promoter region near the transcription start site of the ITIH5 tumor suppressor gene in leukemia cell lines and primary samples from patients with acute myeloid leukemia (AML) as well as the potential use of demethylating agents to restore a demethylated state of the promoter. Aberrant ITIH5 promoter hypermethylation occurred in 15 of 104 (14.4%) diagnostic AML samples. There were no statistically significant correlations between the ITIH5 methylation status and clinical prognostic parameters. Our results indicate that aberrant ITIH5 promoter hypermethylation is a novel epigenetic event in AML.

Sequence of administration and methylation of SOCS3 may govern response to gemtuzumab ozogamicin in combination with conventional chemotherapy in patients with refractory or relapsed acute myelogenous leukemia (AML).

In older patients suffering from acute myelogenous leukemia (AML), aggressive chemotherapy is accompanied with high treatment-related morbidity and mortality. Gemtuzumab ozogamicin (GO), a humanized monoclonal anti-CD33 antibody, represents a well tolerated treatment option, but optimal treatment schedules are still unknown. Additionally, Suppressor of cytokine signaling 3 (SOCS3) inhibits the CD33-induced block on cytokine-induced proliferation. Consequently, a variable response of AML cells to anti-CD33-targeted therapy may be caused by modulation of SOCS3 expression. Twenty-four patients with refractory or relapsed CD33-positive AML received GO as a single agent before or after conventional chemotherapy. The methylation status of the SOCS3 CpG island was assessed by methylation-specific polymerase chain reaction. Response (RR) and overall survival (OS) were significantly higher in 16 patients receiving chemotherapy before GO (RR 81%, OS 14.8 months) compared to three patients who received GO single agent therapy (RR 33%, OS 7.2 months) or 16 with GO before chemotherapy (RR 0% OS 2.2 months, P = 0.01 for RR and P < 0.001 for OS). Methylation of the SOCS3 CpG island was found in 8/24 patients. There was a trend towards a higher RR and longer OS in patients with SOCS3 hypermethylation (RR 86%, OS 25.1 months) compared to unmethylated SOCS3 (RR 56%, OS 10.3 months, P = 0.09). Administration of GO a few days after chemotherapy seems to provide better response and survival compared to administration of GO directly before chemotherapy. The potential role of SOCS3 hypermethylation as a biomarker should be further investigated in patients undergoing GO containing therapies.

[Anemia and severe thrombocytopenia in celiac disease]. / Anämie und schwere Thrombozytopenie bei Sprue.

BACKGROUND: The frequency of diagnosis of celiac disease has increased since the introduction of serologic testing. The number of patients in whom extraintestinal symptoms reflect the initial manifestation is rising. Common symptoms are changes in blood counts, which can arise from changes in all cell lineages. Among these, iron deficiency anemia is very common, but also thrombocytosis and thrombocytopenia have been reported to manifest themselves within the framework of celiac disease. CASE REPORT: The authors report on a patient with malnutrition, macrocytic anemia, and pronounced thrombocytopenia. Based on changes of peripheral blood smear and endoscopic result, celiac disease was suspected that could be confirmed by histology of duodenal biopsies. The thrombocytopenia was reversible after initiation of gluten-free diet and folic acid substitution. In addition, clinical symptoms resolved and hematologic reconstitution could be observed. CONCLUSION: Similar deficiencies have almost exclusively been observed in patients with increased folic acid requirements during pregnancy or intensive care. Celiac disease must be taken into consideration, if changes in blood counts occur associated with gastrointestinal symptoms.

Successful treatment of hepatic encephalopathy in a patient with acute lymphoblastic leukemia.

Infiltration of the liver with consecutive severe dysfunction is rarely seen in adult acute lymphoblastic leukemia (ALL). We describe a case of a 32-year-old woman with severe icterus, thrombocytopenia, neutropenia and hepatosplenomegaly. ALL was diagnosed. One day after admission, she developed hepatic encephalopathy with ammonia concentrations in plasma >100 micromol/l. Hepatic infiltration was presumed and chemotherapy was initiated immediately which led to resolution of hepatic encephalopathy and complete hematological remission. Clinicians should be aware of unusual presentations of ALL and difficulties for the application of chemotherapy in patients with liver failure.

Progressive chromatin repression and promoter methylation of CTNNA1 associated with advanced myeloid malignancies.

Complete loss or deletion of the long arm of chromosome 5 is frequent in myelodysplastic syndrome (MDS) and acute myelogenous leukemia (AML). The putative gene(s) deleted and responsible for the pathogenesis of these poor prognosis hematologic disorders remain controversial. This study is a comprehensive analysis of previously implicated and novel genes for epigenetic inactivation in AML and MDS. In 146 AML cases, methylation of CTNNA1 was frequent, and more common in AML patients with 5q deletion (31%) than those without 5q deletion (14%), whereas no methylation of other 5q genes was observed. In 31 MDS cases, CTNNA1 methylation was only found in high-risk MDS (>or=RAEB2), but not in low-risk MDS (

Targeted restoration of down-regulated DAPK2 tumor suppressor activity induces apoptosis in Hodgkin lymphoma cells.

Death-associated protein kinase 2 (DAPK2) is a calcium/calmodulin-regulated proapoptotic serine/threonine kinase that acts as a tumor suppressor. Here we show that DAPK2 is down-regulated in Hodgkin lymphoma-derived tumor cell lines and that promoter-region hypermethylation is one mechanism for DAPK2 inactivation. To determine whether selective reconstitution of DAPK2 catalytic activity in these cells could induce apoptosis, we created a fusion protein comprising a human CD30 ligand conjugated to a human DAPK2 calmodulin-deletion mutant. Thus, recombinant immunokinase DAPK2'-CD30L has a constitutive kinase activity with enhanced proapoptotic function. We show that this immunokinase fusion protein inhibits cell proliferation and induces apoptotic cell death specifically in CD30/DAPK2-negative tumor cell lines. This proof-of-concept study provides the first demonstration of therapeutic strategies based on the restoration of a defective, tumor-suppressing kinase activity by a novel class of recombinant immunotherapeutics.

Inhibitor of differentiation 4 (Id4) is a potential tumor suppressor in prostate cancer.

BACKGROUND: Inhibitor of differentiation 4 (Id4), a member of the Id gene family is also a dominant negative regulator of basic helix loop helix (bHLH) transcription factors. Some of the functions of Id4 appear to be unique as compared to its other family members Id1, Id2 and Id3. Loss of Id4 gene expression in many cancers in association with promoter hypermethylation has led to the proposal that Id4 may act as a tumor suppressor. In this study we provide functional evidence that Id4 indeed acts as a tumor suppressor and is part of a cancer associated epigenetic re-programming. METHODS: Data mining was used to demonstrate Id4 expression in prostate cancer. Methylation specific polymerase chain reaction (MSP) analysis was performed to understand molecular mechanisms associated with Id4 expression in prostate cancer cell lines. The effect of ectopic Id4 expression in DU145 cells was determined by cell cycle analysis (3H thymidine incorporation and FACS), expression of androgen receptor, p53 and cyclin dependent kinase inhibitors p27 and p21 by a combination of RT-PCR, real time-PCR, western blot and immuno-cytochemical analysis. RESULTS: Id4 expression was down-regulated in prostate cancer. Id4 expression was also down-regulated in prostate cancer line DU145 due to promoter hyper-methylation. Ectopic Id4 expression in DU145 prostate cancer cell line led to increased apoptosis and decreased cell proliferation due in part by an S-phase arrest. In addition to S-phase arrest, ectopic Id4 expression in PC3 cells also resulted in prolonged G2/M phase. At the molecular level these changes were associated with increased androgen receptor (AR), p21, p27 and p53 expression in DU145 cells. CONCLUSION: The results suggest that Id4 acts directly as a tumor suppressor by influencing a hierarchy of cellular processes at multiple levels that leads to a decreased cell proliferation and change in morphology that is possibly mediated through induction of previously silenced tumor suppressors.

Cisplatin as single-agent chemotherapy in patients with liver dysfunction due to metastases.

BACKGROUND: Chemotherapeutic options are often limited for patients with hepatic dysfunction induced by advanced metastases. The toxicity and efficacy of cytotoxic drugs are often unpredictable due to altered drug activation or inactivation and excretion. Therefore, numerous chemotherapeutic agents should not be administered to patients with liver failure. PATIENTS AND METHODS: We retrospectively analysed 14 patients with solid tumours presenting with liver dysfunction induced by metastasis who were treated with cisplatin single-agent chemotherapy. RESULTS: Tolerance of therapy was acceptable with 1 grade I and 1 grade II renal toxicity. 6 patients experienced grade III haematological toxicity. Partial remission of the disease was observed in 6 cases, and 6 patients could receive combination chemotherapy after improvement of liver function. The median overall survival of the patient cohort was 4.8 months. CONCLUSION: Cisplatin monotherapy may thus be considered as a treatment option for patients with liver dysfunction induced by different solid tumours.