Preserved levels of uninvolved immunoglobulins are independently associated with favorable outcome in patients with symptomatic multiple myeloma.

Suppression of uninvolved immunoglobulins is common in multiple myeloma (MM) but the prognostic significance of this phenomenon has not been assessed. We evaluated the prognostic significance of the preservation of uninvolved immunoglobulins in 1755 consecutive, unselected, patients with newly diagnosed, symptomatic MM with pre-therapy immunoglobulin levels measured by nephelometry. Suppression of at least one uninvolved immunoglobulin was observed in 87% of patients and was more common in patients with immunoglobulin A myeloma, those aged over 65 years, in patients with advanced-International Staging System (ISS) stage, extensive-bone marrow infiltration, anemia, low platelet counts, high levels of serum M-monoclonal protein or renal dysfunction. Patients with preserved immunoglobulins had a better survival than patients with suppressed immunoglobulins (median survival 55 vs 41.5 months, P<0.001). In multivariate analysis, preservation of uninvolved immunoglobulins was independently associated with better survival (hazard ratio: 0.781, 95% confidence interval: 0.618-0.987, P=0.039); irrespective of the treatment. In a subset of 500 patients, which were strictly followed for disease progression, preservation of uninvolved immunoglobulins was associated with a significantly longer progression-free survival (60 vs 25 months, P<0.001), independently of other common prognostic factors. In conclusion, preservation of uninvolved immunoglobulins in newly diagnosed patients with symptomatic MM was independently associated with long term disease control and improved survival.

Epigenetic status of argininosuccinate synthetase and argininosuccinate lyase modulates autophagy and cell death in glioblastoma.

Arginine deprivation, either by nutritional starvation or exposure to ADI-PEG20, induces adaptive transcriptional upregulation of ASS1 and ASL in glioblastoma multiforme ex vivo cultures and cell lines. This adaptive transcriptional upregulation is blocked by neoplasia-specific CpG island methylation in either gene, causing arginine auxotrophy and cell death. In cells with methylated ASS1 or ASL CpG islands, ADI-PEG20 initially induces a protective autophagic response, but abrogation of this by chloroquine accelerates and potentiates cytotoxicity. Concomitant methylation in the CpG islands of both ASS1 and ASL, observed in a subset of cases, confers hypersensitivity to ADI-PEG20. Cancer stem cells positive for CD133 and methylation in the ASL CpG island retain sensitivity to ADI-PEG20. Our results show for the first time that epigenetic changes occur in both of the two key genes of arginine biosynthesis in human cancer and confer sensitivity to therapeutic arginine deprivation. We demonstrate that methylation status of the CpG islands, rather than expression levels per se of the genes, predicts sensitivity to arginine deprivation. Our results suggest a novel therapeutic strategy for this invariably fatal central nervous system neoplasm for which we have identified robust biomarkers and which overcomes the limitations to conventional chemotherapy imposed by the blood/brain barrier.

Clinical trial design in biosimilar drug development.

In contrast to most drugs which are chemically synthesized and have a known structure, biological drugs are derived from living organisms or their products. Biologicals are structurally more complex and unique from chemically synthesized small drug molecules because of their larger size and intricate manufacturing process. Secondary to their protein structure, they are also more prone to acute and chronic immune responses. Biosimilars are intended to offer comparable safety and efficacy relative to reference brand biologicals, yet they are not generic alternatives to the original compounds and so are currently not considered interchangeable. Given their structural complexity, multifaceted manufacturing processes and risk for immunogenicity, biosimilars require class-specific regulatory approval pathways. Here we seek to provide a general overview of clinical trial design in the era of biosimilar drug development. This will include a review of the regulatory requirements for clinical trials in Europe and the United States, followed by a review of two biosimilars that have recently reported results of randomized trials against branded biologicals.

The collagen prolyl hydroxylases are novel transcriptionally silenced genes in lymphoma.

BACKGROUND: Prolyl hydroxylation is a post-translational modification that affects the structure, stability and function of proteins including collagen by catalysing hydroxylation of proline to hydroxyproline through action of collagen prolyl hydroxylases3 (C-P3H) and 4 (C-P4H). Three C-P3Hs (nomenclature was amended according to approval by the HGNC symbols and names at http://www.genenames.org/ and Entrez database at http://www.ncbi.nlm.nih.gov/gene) leucineproline-enriched proteoglycan (leprecan) 1 (Lepre1), leprecan-like 1 (Leprel1), leprecan-like 2 (Leprel2) and two paralogs Cartilage-Related Protein (CRTAP) and leprecan-like 4 (Leprel4) are found in humans. The C-P4Hs are tetrameric proteins comprising a variable α subunit, encoded by the P4HA1, P4HA2 and P4HA3 genes and a constant ß subunit encoded by P4HB. METHODS: We used RT-PCR, qPCR, pyrosequencing, methylation-specific PCR, western blotting and immunohistochemistry to investigate expression and regulation of the C-P3H and C-P4H genes in B lymphomas and normal bone marrow. RESULTS: C-P3H and C-P4H are downregulated in lymphoma. Down-regulation is associated with methylation in the CpG islands and is detected in almost all common types of B-cell lymphoma, but the CpG islands are unmethylated or methylated at lower levels in DNA isolated from normal bone marrow and lymphoblastoid cell lines. Methylation of multiple C-P3H and C-P4H genes is present in some lymphomas, particularly Burkitt's lymphoma. CONCLUSIONS: Methylation of C-P3H and C-P4H is common in B lymphomas and may have utility in differentiating disease subtypes.

Promoter methylation of argininosuccinate synthetase-1 sensitises lymphomas to arginine deiminase treatment, autophagy and caspase-dependent apoptosis.

Tumours lacking argininosuccinate synthetase-1 (ASS1) are auxotrophic for arginine and sensitive to amino-acid deprivation. Here, we investigated the role of ASS1 as a biomarker of response to the arginine-lowering agent, pegylated arginine deiminase (ADI-PEG20), in lymphoid malignancies. Although ASS1 protein was largely undetectable in normal and malignant lymphoid tissues, frequent hypermethylation of the ASS1 promoter was observed specifically in the latter. A good correlation was observed between ASS1 methylation, low ASS1 mRNA, absence of ASS1 protein expression and sensitivity to ADI-PEG20 in malignant lymphoid cell lines. We confirmed that the demethylating agent 5-Aza-dC reactivated ASS1 expression and rescued lymphoma cell lines from ADI-PEG20 cytotoxicity. ASS1-methylated cell lines exhibited autophagy and caspase-dependent apoptosis following treatment with ADI-PEG20. In addition, the autophagy inhibitor chloroquine triggered an accumulation of light chain 3-II protein and potentiated the apoptotic effect of ADI-PEG20 in malignant lymphoid cells and patient-derived tumour cells. Finally, a patient with an ASS1-methylated cutaneous T-cell lymphoma responded to compassionate-use ADI-PEG20. In summary, ASS1 promoter methylation contributes to arginine auxotrophy and represents a novel biomarker for evaluating the efficacy of arginine deprivation in patients with lymphoma.

NT5E CpG island methylation is a favourable breast cancer biomarker.

BACKGROUND: Relapse risk assessment and individual treatment recommendations remain suboptimal for breast cancer patients. In the light of existing preclinical and clinical data, we studied NT5E (5'-nucleotidase, ecto) expression and NT5E CpG island methylation in breast cancer. METHODS: We used RT-PCR, qPCR, methylation-specific PCR and pyrosequencing to analyse NT5E in breast carcinoma cell lines and primary and breast carcinomas. RESULTS: NT5E CpG island methylation was inversely associated with NT5E expression in breast carcinoma cell lines. In clinical series, patients whose primary tumours had NT5E CpG island methylation were less likely to develop metastasis (P=0.003, OR=0.34, 95% CI: 0.17-0.69). In 3/4 paired samples, NT5E was methylated in primary tumours and demethylated in CNS metastases. Patients progressing to non-visceral as compared with visceral metastases were more likely to have NT5E CpG island methylation in primary tumours (P=0.01, OR=11.8). Patients with tumours lacking detectable methylation had shorter disease-free survival (DFS) (P=0.001, HR=2.7) and overall survival (OS) (P=0.001, HR=3). The favourable prognostic value of NT5E methylation was confirmed in oestrogen receptor negative (P=0.011, HR=3.27, 95% CI: 1.31-8.12) and in triple negative cases (P=0.004; HR=6.2, 95% CI: 1.9-20). Moreover, we observed a more favourable outcome to adjuvant chemotherapy in patients whose tumours were positive for NT5E CpG island methylation: DFS (P=0.0016, HR=5.1, 95% CI: 1.8-14.37) and OS (P=0.0005, HR=7.4, 95% CI: 2.416-23.08). CONCLUSION: NT5E CpG island methylation is a promising breast cancer biomarker.

NT5E (CD73) is epigenetically regulated in malignant melanoma and associated with metastatic site specificity.

BACKGROUND: Novel prognostic biomarkers and therapeutic strategies are urgently required for malignant melanoma. Ecto-5-prime-nucleotidase (NT5E; CD73) overexpression has been reported in several human cancers. The mechanism(s) underlying deregulated expression and the clinical consequences of changes in expression are not known. METHODS: We used RT-PCR, qPCR, methylation-specific PCR and pyrosequencing to analyse expression and regulation of NT5E in malignant melanoma cell lines and primary and metastatic melanomas. RESULTS: NT5E is subject to epigenetic regulation in melanoma. NT5E mRNA is downregulated by methylation-dependent transcriptional silencing in the melanoma cell lines SKMel2, SKMel23, WM35, Mel501, Mel505 and C81-61 and expression is reactivated by azacytidine. In contrast, the CpG island is unmethylated and the gene expressed in cultured normal melanocytes. In clinical cases of melanoma, methylation in the NT5E CpG island occurs in both primary and metastatic melanomas and correlates with transcriptional downregulation of NT5E mRNA. Relapse with metastatic disease, particularly to the visceral sites and brain, is more common in primary melanomas lacking NT5E methylation. Primary melanomas with methylation in NT5E show limited metastatic potential or more commonly metastasise predominantly to nodal sites rather than viscera and brain (P=0.01). CONCLUSION: Deregulation of NT5E expression in melanoma occurs via epigenetic changes in the NT5E CpG island. Confirmation of our results in larger clinical series would support the candidacy of NT5E as a clinical biomarker in melanoma, which could be applied in both primary and relapsed disease. Inhibition of NT5E may have therapeutic potential in melanoma, particularly in patients with more aggressive disease metastatic to viscera or the brain.

DUSP16 is an epigenetically regulated determinant of JNK signalling in Burkitt's lymphoma.

BACKGROUND: The mitogen-activated protein kinase (MAPK) phosphatases or dual specificity phosphatases (DUSPs) are a family of proteins that catalyse the inactivation of MAPK in eukaryotic cells. Little is known of the expression, regulation or function of the DUSPs in human neoplasia. METHODS: We used RT-PCR and quantitative PCR (qPCR) to examine the expression of DUSP16 mRNA. The methylation in the DUSP16 CpG island was analysed using bisulphite sequencing and methylation-specific PCR. The activation of MAPK was determined using western blotting with phospho-specific antibodies for extra-cellular signal-related kinase (ERK), p38 and c-Jun N-terminal kinase (JNK). The proliferation of cell lines was assessed using the CellTiter 96 Aqueous One assay. RESULTS: The expression of DUSP16, which inactivates MAPK, is subject to methylation-dependent transcriptional silencing in Burkitt's Lymphoma (BL) cell lines and in primary BL. The silencing is associated with aberrant methylation in the CpG island in the 5' regulatory sequences of the gene blocking its constitutive expression. In contrast to BL, the CpG island of DUSP16 is unmethylated in other non-Hodgkin's lymphomas (NHLs) and epithelial malignancies. In BL cell lines, neither constitutive nor inducible ERK or p38 activity varied significantly with DUSP16 status. However, activation of JNK was increased in lines with DUSP16 methylation. Furthermore, methylation in the DUSP16 CpG island blocked transcriptional induction of DUSP16, thereby abrogating a normal physiological negative feedback loop that limits JNK activity, and conferred increased cellular sensitivity to agents, such as sorbitol and anthracycline chemotherapeutic agents that activate JNK. CONCLUSION: DUSP16 is a new epigenetically regulated determinant of JNK activation in BL.

The role of immune suppression and HHV-8 in the increasing incidence of HIV-associated multicentric Castleman's disease.

BACKGROUND: In HIV cohorts with access to highly active antiretroviral therapy (HAART), the incidence of Kaposi's sarcoma (KS) is falling; however, the incidence of multicentric Castleman's disease (MCD) in HIV has not previously been described. METHODS: The incidence of HIV-associated MCD was calculated from a prospective HIV database with 56 202 patient-years of follow-up and compared with KS. Univariate and multivariate analyses were carried out to identify factors associated with MCD. Plasma human herpesvirus (HHV)-8 DNA levels were measured in HIV-seropositive individuals with newly diagnosed MCD (n = 24), KS (n = 72), HIV-associated lymphoma (n = 74) and HIV-positive controls (n = 53). RESULTS: From 24 cases of HIV-associated MCD, the incidence measured 4.3/10,000 patient-years [95% confidence interval (CI) 2.7-6.4]. The incidence in the pre-HAART (1983-1996), early-HAART (1997-2001) and later HAART (2002-2007) eras were 2.3 (95% CI 0.02-4.2), 2.8 (95% CI 0.9-6.5) and 8.3 (95% CI 4.6-12.6), respectively, representing a statistically significant increase over time (P < 0.05). In contrast, from 1180 cases of KS, the incidence in this cohort decreased with time. Multivariate analysis demonstrated that a nadir CD4 count >200/mm(3), increased age, no previous HAART exposure and non-Caucasian ethnicity were all associated with an increased risk of MCD. Plasma HHV-8 DNA levels were higher in patients with newly diagnosed MCD than with KS, lymphomas or HIV-positive controls (Mann-Whitney U-test, P < 0.0001). CONCLUSIONS: The incidence of HIV-associated MCD is increasing. It appears to occur more frequently in older HIV-positive individuals with well-preserved immune function.

Spontaneous splenic haematoma in a multiple myeloma patient receiving pegfilgrastim support.

Growth factors are a significant advance in the supportive care of patients with cancer with a wide range of indications. Frequent side effects of G-CSF include bone pain, headache, fatigue and nausea. We report a case of subcapsular splenic haematoma following pegfilgrastim administration in a 65-year old patient with multiple myeloma. Proposed mechanisms accounting for splenic enlargement include extramedullary haemopoiesis, intrasplenic infiltration by mature and immature myeloid cells and intrasplenic stem cell homing and proliferation. The risk of spontaneous splenic rupture is difficult to quantify. Physicians should be aware of this life-threatening condition and early diagnosis can be difficult since anemia and splenomegaly are common findings in haematologic patients.

The presentation and survival of patients with non-cutaneous AIDS-associated Kaposi's sarcoma.

BACKGROUND: Acquired immune deficiency syndrome related Kaposi's sarcoma (AIDS-KS) remains a significant cause of morbidity and mortality. We describe for the first time a proportion of patients with AIDS-KS who presented with no evidence of cutaneous disease. PATIENTS AND METHODS: From our cohort of 5932 individuals infected with the human immunodeficiency virus (HIV-1) treated in the HAART era, 319 were identified with KS. Of these, 11 patients (5.4%) were diagnosed with KS without the presence of any cutaneous disease. We compared their survival, clinical, immunological and virological characteristics to other individuals with KS. RESULTS: There were no statistically significant differences in survival, CD4 count or HIV viral load at KS presentation. We observed that tumour-associated oedema (P = 0.046) and non-oral gastrointestinal KS (P = 0.042) were significantly more common in patients with non-cutaneous KS. Only one case of non-cutaneous KS was observed prior to the era of highly active anti-retroviral therapy (HAART). CONCLUSIONS: Non-cutaneous KS is a recognisable condition; patients should be treated with the standard of care as their prognosis is not inferior. This is likely to reflect a strong immune response, in the era of HAART.

Recombinant human erythropoietin therapy in a transfusion-dependent beta-thalassemia major patient.

We report on a 28-year-old patient with transfusion-dependent beta-thalassemia major, who was treated effectively with recombinant human erythropoietin (rHuEpo). rHuEpo promotes the differentiation and proliferation of erythroid cells, induces the production of fetal hemoglobin (HbF), and could be useful in the treatment of some selected transfusion-dependent thalassemia patients. Prior to rHuEpo treatment, the patient was on a regular blood transfusion regimen. Splenectomy did not decrease the transfusion requirements. Additionally, red cell alloimmunization had developed; therefore, we decided to start rHuEpo treatment (Eprex, Jansen Cilag, Greece) in an attempt to improve his anemia and the quality of life. Our patient responded well to rHuEpo treatment and was able to extend the intervals between transfusions from 10-14 to 55-65 days and to sustain a pretransfusion hemoglobin level above 7 g/dl. HbF levels were slightly increased from 55% to 60-65%. Indicators of vascular endothelial activation [serum endothelin-3, intracellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin] were decreased during treatment. rHuEpo was well tolerated without complications. rHuEpo treatment seemed to have had a beneficial effect and to have improved the quality of life in beta-thalassemia major, although it did have a slight effect on HbF levels, suggesting other possible mechanisms of rHuEpo action.

Treatment of plasma cell leukemia with vincristine, liposomal doxorubicin and dexamethasone.

Primary plasma cell (PCL) leukemia is a rare lymphoproliferative disorder characterized by a malignant proliferation of plasma cells in the bone marrow and peripheral blood. Survival with standard therapy using melphalan is very poor. Doxorubicin encapsulated with liposomes has less cardiotoxicity, is at least as efficient and has fewer side effects than conventional doxorubicin. Two female patients (69 and 54 yr old) with primary PCL are described in this study. They both received a modified form of VAD (vincristine, doxorubicin and dexamethasone), a regimen which includes liposomal doxorubicin (40 mg/m2 for 1 d), vincristine (2 mg for 1 d) and dexamethasone 40 mg per os on days 1-4, 9-12 and 17-20. A disease evaluation of the first patient after six courses of the modified \VAD regimen showed no plasma cells in the peripheral blood, a decrease in the serum M protein level and a plasma cell infiltration in the bone marrow of less than 5%. The patient died from a cardiac episode 24 months post-diagnosis, while she was in complete hematological remission. The second patient also exhibited good tolerance to liposomal doxorubicin with no side effects, achieved complete haematological remission and remains in good condition 7 months after the last VAD administration. These results suggest that this modified form of VAD regimen also seems to work in PCL and is well tolerated with no side effects.

Serum levels of IL-6 and its soluble receptor (sIL-6R) in Waldenström's macroglobulinemia.

BACKGROUND: Interleukin-6 (IL-6) is a multifunctional cytokine that plays roles in the immune response, inflammation and hematopoiesis. Serum IL-6 levels have reported to reflect disease severity and high tumor burden in multiple myeloma (MM) patients and to correlate with several other laboratory parameters. Serum-soluble IL-6 receptor (sIL-6R) plays an agonist role in IL-6 signaling, enhancing its biological activity tenfold. PURPOSE-METHODS: We measured IL-6 and sIL-6R levels in 11 patients (7 male, 4 female, mean age 66.9 yr) with Waldenström's macrobulinemia (WM) using a commercially available enzyme-linked immunoassay in order to investigate their biological role and to find any possible relationship with disease severity, tumor burden or response to treatment. RESULTS: Serum IL-6 and sIL-6R concentrations at diagnosis were significantly higher than in healthy controls (Mann Whitney U-test, p < 0.001 and p < 0.01, respectively). Patients who were effectively treated had a significant reduction in IL-6 levels (p = 0.017). With regard to sIL-6R levels, no specific tendency was observed. In some of the responsive patients the levels increased whereas in others they decreased. No correlation was found between IL-6 and sIL-6R levels at diagnosis (p = 0.9, r = 0.036) or after treatment (p = 0.083, r = 0.3). CONCLUSIONS: Our results suggest that IL-6 may be a marker reflecting tumor burden, disease severity and response to treatment in WM. With regard to sIL-6R, we believe that it does not seem to be of much value, and its role remains to be clarified. However, future studies are needed to confirm and further extend the present results.

Investigation for the presence of anti-erythropoietin antibodies in patients with myelodysplastic syndromes.

OBJECTIVES: Recombinant human erythropoietin (rHuEpo) improves anemia in 25% of patients with myelodysplastic syndromes (MDS). The variable and sometimes low response rate to rHuEpo treatment raises the question whether the existence of autoantibodies against erythropoietin (epo) is partially responsible. In the present study we investigated the presence of anti-epo autoantibodies in MDS patients. METHODS: Forty-three patients with MDS were studied. Sixteen patients had refractory anemia (RA), 13 had RA with ringed sideroblasts, 3 had RA with excess of blasts (RAEB), 9 had RAEB in transformation and 2 patients had chronic myelomonocytic leukemia. They were divided in 3 groups according to rHuEpo treatment. Group A consisted of 10 patients who did not receive rHuEpo treatment. Group B included 13 patients who were on rHuEpo treatment (150 IU/kg subcutaneously, 3 times weekly) showing an increase of hemoglobin (Hb) values or reduction of transfusion requirements and Group C consisted of 20 patients who did not respond or stopped responding to rHuEpo treatment. Laboratory studies consisted of a complete blood cell count, measurement of serum epo and determination of anti-epo antibodies using ELISA. RESULTS: There were no significant differences with regard to age and sex among the three groups. No autoantibodies against epo were found in the examined sera, apart from a female patient from group A who showed a low positive titer. CONCLUSION: We suggest that anti-epo autoantibodies do not contribute to the development of MDS-related anemia and are not responsible for the modest response to rHuEpo treatment. Further investigation is needed to identify possible reasons for the low response rate to rHuEpo treatment.

The role of cytokines in sickle cell disease.

Sickle cell disease (SCD) is characterized by chronic hemolysis, frequent infections, and recurrent occlusions of microcirculation, which cause painful crises and result in chronic organ damage and failure. Occlusions of the microcirculation and infections are important factors that stimulate the production of cytokines and acute-phase proteins. Cytokines seem to be involved with several possible mechanisms in the pathogenesis of vasoocclusive phenomena in SCD: vascular endothelial activation, induction of red-cell adhesiveness to vascular endothelium, induction of neutrophil adhesiveness to endothelium, development of vascular intimal hyperplasia, platelet activation, endothelin-1 production, and dysregulation of endothelial apoptosis. Cytokines are also thought to be involved in the regulation of hemopoiesis, the inhibition of immune functions, and the development of growth deficits. Investigation of cytokines in SCD patients will elucidate the pathogenesis of the disease and its complications and may help in assessing disease severity and prognosis.

Alpha-2-macroglobulin and interleukin-6 levels in steady-state sickle cell disease patients.

Endothelial activation and subclinical microvascular occlusions are an ongoing process during steady-state sickle cell disease, leading to interleukin production and an acute-phase response. Alpha-2-macroglobulin (alpha2M) is an acute-phase protein mainly regulated by interleukin-6 (IL-6). On the other hand, alpha2M acts as a carrier protein for IL-6 during inflammatory stress. The purpose of this study is to further assess the interactions between IL-6 and alpha2M as potent modulators of inflammatory reactions during the steady state of sickle cell disease. We measured alpha2M and IL-6 levels in 21 patients (12 male, 9 female; age range 12-44 years) in the steady state of sickle cell disease. Four patients had homozygous sickle cell anaemia and 17 had double heterozygous sickle cell/beta-thalassaemia. Diagnostic quantification of alpha2M was performed by rate nephelometry. Commercial enzyme immunoassay test kits were used for the quantitative measurement of IL-6. The alpha2M and IL-6 levels were compared to the values obtained from healthy volunteers. Mean values (+/- SD) of alpha2M and IL-6 were found to be significantly increased (p < 0.0005) in the patients (alpha2M: 337.2 +/- 104 mg/dl; IL-6: 4 +/- 2.1 pg/ml) compared to the healthy controls (alpha2M: 204.2 +/- 45.8 mg/dl; IL-6: 1.15 +/- 2.5 pg/ml). IL-6 values were positively correlated with alpha2M levels (r = 0.61, p < 0.01). We observed increased alpha2M and IL-6 levels in steady-state sickle cell disease and a positive correlation between these two inflammatory mediators. We suggest that alpha2M is a potent modulator of the inflammatory reaction and tissue repair mechanism during steady-state microvascular occlusions. Elucidating the role of alpha2M in sickle cell disease could lead to the development of novel strategies and therapies for preventing the harmful systemic or local effects of excess cytokine production.