Blockade of ubiquitin-conjugating enzyme CDC34 enhances anti-myeloma activity of Bortezomib/Proteasome inhibitor PS-341

The ubiquitin-conjugating enzyme CDC34 (UBC3) is linked to cell cycle progression in diverse cell types; however, its role in multiple myeloma (MM) pathogenesis is unclear. Here, we show that CDC34 is highly expressed in patient MM cells and MM cell lines versus normal cells. Blocking CDC34 using a dominant-negative strategy enhances the anti-MM activity of Bortezomib/Proteasome inhibitor PS-341, dexamethasone (Dex) and 2-Methoxyestradiol (2ME2). The expression of wild-type CDC34 reduces Dex-induced cytotoxicity in MM cells. Moreover, inhibition of CDC34 enzymatic activity abrogates interleukin-6-induced protection against Dex-induced apoptosis. Together, these findings provide evidence that (1) CDC34 expression is associated with growth and survival of MM cells and (2) blocking CDC34 activity not only enhances anti-MM activity of Bortezomib and 2ME2 but also overcomes IL-6-triggered Dex-resistance.     

Insulin-like growth factor-1 induces adhesion and migration in human multiple myeloma cells via activation of beta1-integrin and phosphatidylinositol 3'-kinase/AKT signaling

Insulin-like growth factor-1 (IGF-I) is a growth and survival factor in human multiple myeloma (MM) cells. Here we examine the effect of IGF-I on MM cell adhesion and migration, and define the role of beta1 integrin in these processes. IGF-I increases adhesion of MM.1S and OPM6 MM cells to fibronectin (FN) in a time- and dose-dependent manner, as a consequence of IGF-IR activation. Conversely, blocking anti-beta1 integrin monoclonal antibody, RGD peptide, and cytochalasin D inhibit IGF-I-induced cell adhesion to FN. IGF-I rapidly and transiently induces association of IGF-IR and beta1 integrin, with phosphorylation of IGF-IR, IRS-1, and p85(PI3-K). IGF-I also triggers phosphorylation of AKT and ERK significantly. Both IGF-IR and beta1 integrin colocalize to lipid rafts on the plasma membrane after IGF-I stimulation. In addition, IGF-I triggers polymerization of F-actin, induces phosphorylation of p125(FAK) and paxillin, and enhances beta1 integrin interaction with these focal adhesion proteins. Importantly, using pharmacological inhibitors of phosphatidylinositol 3'-kinase (PI3-K) (LY294002 and wortmannin) and extracellular signal-regulated kinase (PD98059), we demonstrate that IGF-I-induced MM cell adhesion to FN is achieved only when PI3-K/AKT is activated. IGF-I induces a 1.7-2.2 (MM.1S) and 2-2.5-fold (OPM6) increase in migration, whereas blocking anti-IGF-I and anti-beta1 integrin monoclonal antibodies, PI3-K inhibitors, as well as cytochalasin D abrogate IGF-I-induced MM cell transmigration. Finally, IGF-I induces adhesion of CD138+ patient MM cells. Therefore, these studies suggest a role for IGF-I in trafficking and localization of MM cells in the bone marrow microenvironment. Moreover, they define the functional association of IGF-IR and beta1 integrin in mediating MM cell homing, providing the preclinical rationale for novel treatment strategies targeting IGF-I/IGF-IR in MM.     

Role for high-dose therapy with autologous hematopoietic stem cell support in Waldenstrom's macroglobulinemia

Despite effectiveness of standard chemotherapy regimens, complete responses are infrequent in Waldenstrom's macroglobulinemia (WM) and there are no cures. Since WM shares certain biological and clinical features with myeloma, including responsiveness to alkylating agents, evaluation of high-dose therapy (HDT) with transplant, which is effective in myeloma, is an obvious next step in an effort to achieve high response rates and improve survival. Due to the indolent nature of the disease and older patients with comorbidities, such evaluations have been infrequent in the past. We have evaluated the safety and efficacy of high-dose melphalan with peripheral blood stem cell (PBSC) support in eight patients between the ages of 45 and 69 years with WM. Adequate numbers of stem cells were collected in six patients; however, two patients with more extensive prior fludarabine therapy failed to collect adequate cells and required a second attempt at stem cell collection. Seven patients were treated with melphalan 200 mg/m(2), including two patients who received tandem transplants; one patient received melphalan 140 mg/m(2) with total body irradiation (TBI). There was no treatment-related mortality and toxicities were manageable. Recovery of bone marrow after transplant was prompt except in one patient with extensive prior use of fludarabine. All the eight patients achieved at least partial response (PR), including one complete response (CR). Five patients are alive and with out relapse (77+ to 6+ months post-transplant). Other investigators have reported similar experience suggesting safety and efficacy of HDT in WM. However, therapy with purine analogues leads to stem cell damage with decreased ability to collect adequate numbers of stem cells. This suggests that the PBSCs should preferably be procured prior to extensive use of purine analogues. Future strategies in WM will include a plan to evaluate the role of HDT along with biological agents, role of purging using rituximab, post-HDT maintenance strategies (including immunotherapy), and evaluation of nonmyeloablative regimens containing fludarabine to achieve higher response rates and improve survival.     

Use of EMLA: is it an injection free alternative?

This study was conducted to evaluate the use of Eutectic Mixture of Local Anesthetics (EMLA) for various clinical procedures such as extraction of the mobile primary teeth, root stumps as well as pulpal therapy procedures in the primary teeth. Thirty children in need of routine dental procedures were selected and procedures were done under a single anesthesia of EMLA. Pain perception and the effectiveness of anesthesia were evaluated with the Eland's color scale and Lickert's scale respectively. Results showed that use of EMLA could to some extent eliminate the use of the needle in the procedures performed especially in pediatric dentistry.     

Acceptability of oesophagogastroduodenoscopy without intravenous sedation: patients' versus endoscopist's perception with special reference to older patients

Objective::This study was undertaken to compare (1) patients'' perception of discomfort with the endoscopist''s perception of patients'' discomfort for the unsedated OGD, (2) tolerability between older (⩾75 years) and younger (<75 years) patients. Design and subjects::A total of 130 consecutive patients attending a day case endoscopy unit were recruited for the study. The patients and endoscopist recorded their assessment using a visual analogue scale (VAS). The results were analysed using non-parametric tests. Thirty patients were excluded from the study based on exclusion criteria. Sixty three (57%) patients were aged ⩾75 years and 37 (43%) were <75 years. Results::A significant difference was noted between patients'' perception of the discomfort and the endoscopist''s assessment of the patient''s discomfort as suggested by the overall higher VAS scores for patients (median 4.9, SD 2.6) than those of the endoscopist (median 2.2, SD 1.2), giving a significant difference in median VAS score of 3.4 (p<0.001). Older and younger patients had similar scores, with median (SD) VAS scores of 4.8 (2.5) for ⩾75 years and 4.9 (2.8) for <75 years. The endoscopist''s median scores for these two groups were 2.2 (1.2) and 2.1 (1.3), respectively. Conclusions::Patients'' discomfort during OGD performed without sedation was greatly underestimated by the endoscopist. There was no significant difference in acceptability between old and the young patients.     

Neuropsychiatric non-motor aspects of Parkinson's disease

Parkinson's disease is often recognised as a motor disease characterised by rest tremor, rigidity, bradykinesia, and postural disturbances. However, there are several non-motor aspects of the disease that are of at least equal importance in the management of patients with Parkinson's disease. They include depression, cognitive impairment, anxiety, and psychosis among others. It is important to recognise them, as they are common and they contribute significantly to patients' morbidity, quality of life, and institutionalisation to long term care homes. In addition to the disease duration and severity, other factors including drugs may contribute to their occurrence. Pathogenesis of these aspects is not fully understood, though there has been a significant increase in the knowledge in recent years. Management of these aspects involves a multidisciplinary approach.     

Increased bone marrow microvessel density in newly diagnosed multiple myeloma carries a poor prognosis.

Solid organ tumors associated with neoangiogenesis, as measured by increased microvessel density (MVD), have poorer prognoses. A similar observation of increased MVD has been made in hematologic malignancies; however, its prognostic significance remains unknown. We investigated changes in MVD in 122 newly diagnosed multiple myeloma patients uniformly treated according to the "Total Therapy" protocol (remission induction followed by tandem autotransplants and interferon maintenance) from a set of 231 patients. MVD was measured as mean of 10 fields (MVD) and the single highest field (SHF) on anti-CD34-stained Zenker-fixed paraffin-embedded bone marrow biopsy sections at 400x magnification. MVD was markedly elevated in this population, with a median of 4.4 vessels/field (range, 0.6 to 55.7), and SHF was 13 vessels/field (range, 2 to 80). When compared to 54 patients with less than 4 MVD, 67 patients with mean MVD of greater than 4 had a significantly inferior median duration of event-free survival (EFS) (2.7 v 4.3 years; P =.03), overall survival (OS) (4.3 v 7.9+ years, P =.006), and median complete response (CR) duration (2.2 v 6.8+ years, P=.003). A similarly significant unfavorable relationship to EFS and OS was present for SHF greater than 13. On multivariate analysis of other previously recognized prognostic factors (beta(2)-microglobulin [beta2M], C-reactive protein [CRP], and Bartl grade; and deletion 13), MVD < or = 4 emerged as a major favorable prognostic variable for OS followed by CRP < or = 4, P=.006. Thus, tumor-associated angiogenesis as reflected by MVD is a biologically relevant and important prognostic feature that can be targeted by antiangiogenesis therapy such as thalidomide, which has remarkable antitumor activity in advanced and refractory multiple myeloma.     

Arsenic trioxide: an emerging therapy for multiple myeloma

Arsenic trioxide can inhibit proliferation and induce apoptosis in multiple myeloma (MM) cells in vitro and in vivo. In addition to affecting tumor growth, arsenic trioxide has been shown to inhibit angiogenesis, suggesting that it may have significant potency in the treatment of MM. Based on these observations, the clinical efficacy of arsenic trioxide was evaluated in patients with advanced refractory MM using a fixed-dose intravenous infusion given daily for a maximum of 60 days. Nine patients were evaluable. All nine had extensive prior therapy; seven had two or more high-dose chemotherapy cycles with autologous stem cell support. All nine patients had cytogenetic abnormalities, and six had chromosome 13 deletions. Of the four patients who completed more than 30 days of arsenic trioxide infusion, two had >50% reduction in myeloma paraprotein, one had stable disease, and one progressed. Of the five patients with <30 days infusion, two had stable disease and three progressed. Thus, on an intent-to-treat basis, two of nine (23%) patients responded (>50% paraprotein reduction). The regimen was well tolerated except for development of cytopenia, which responded to G-CSF, and a grade III pulmonary complication in one patient. In summary, arsenic trioxide has activity in end-stage, high-risk myeloma and deserves further evaluation in earlier-stage disease.