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A “user-friendly” catalyst system generated in situin the absence of alkyne from MoCO6, p-chlorophenol and a polyether over a bed of molecular sieves, is seen to achieve the metathesis of phenylpropyne at 50 °C with a significant rate enhancement depending on the nature of the ether, with 1,2-diphenoxyethane exhibiting the highest efficiency.

p15 and p14/p16 tumor suppressor genes, have been reported to be frequently inactivated by various mechanisms in haematological malignancies such us MM. Alterations of these cell cycle inhibitors in MM display a close correlation with the cell cycle and clinical outcome. We have evaluated by real time quantitative RT-PCR (RQ-PCR) the expression of the p14/p16 and p15 genes in purified bone marrow plasma cells (PBMPC) from MM patients in order to evaluate the possible clinical, biological and prognostic significance of these cell cycle regulators. RNA extracted from purified BMPC from 53 untreated symptomatic MM and a pool of buffy coat from healthy donors (reference value) was analyzed by RQ-PCR using Assays-on-Demand gene expression mixes specific for p14/p16 and p15 genes in an ABI PRISM 7700 SDS (Applied Biosystems, Foster City, CA, USA). Values were corrected with a control gene (ABL). The relative quantification of gene expression was performed through the cycle threshold (CT) increment method. Patients were classified into different groups depending on gene expression values. Thus, according to p15 expression, 29% of patients (n=14) showed higher levels than the control and this group was characterized by the presence of good prognostic markers such us low Lactato dehidrogenase levels (LDH), low b2-microglobulin (B2M) and C-Reactive Protein (CRP) serum levels and absence of monoclonal proteinuria. Similar results were found for p14/p16 expression. Fifteen patients (28%) displayed a high p14/p16 expression and the group was also characterized by good prognostic features: low CRP, B2M and LDH levels. When p14/p16 and p15 genes were simultaneously analyzed, clinical and biological parameters showed a statistically significant correlation with gene expression. Thus patients with low gene expression had a high B2M (≥3 mg/dl) and high C-reactive protein (≥3 mg/dl). As far as survival was concerned, patients with a high p15 expression had a longer overall survival of 100% vs. 58% at 30 months (p=0,01), with the additional value that no deaths have been observed in any such patients. Similar results were observed for the group of patients displaying a high p14/p16 expression since they displayed a much better OS (100% vs. 63% at 30 months, p=0,02). Again, we should note that no deaths have been presented in this group. All these findings were much more evident when the three genes were simultaneously considered. Thus, within the group of 21 patients with at least one of the two genes overexpressed there have been no deaths vs. 11 among the 27 patients with low levels. This resulted in quite different OS curves for the two groups of patients (Figure 1) of 100% vs. 49% at 30 months (p=0,00). In conclusion, these genes significantly determine patients’ outcome thanks to their ability to classify them into different groups with different clinical, biological and outcome characteristics.

Introduction: Waldenström’s Macroglobulinemia (WM) is an uncommon lymphoproliferative disorder characterized by bone marrow infiltration of the lymphoplasmocytic cells and IgM monoclonal gammopathy. The normal counterpart of the WM malignant cell is believed to be a post germinal-center B cell. However, the low frequency of WM has hampered investigation into Immunoglobulin Heavy Chain (IgH) rearrangements in large series of patients and whether preferential use of specific genetic segments or non-functional rearrangements exits. Aim: Molecular characterization in a large cohort of WM patients analyzing their functional, complete VDJH, and non-functional, incomplete DJH, IgH rearrangements, the pattern of somatic hypermutation (SHM) and gene segment usage. Patients and methods: 47 patients with unequivocal diagnosis of WM were included in the study. Bone Marrow samples (always with more than 10% of tumor cell) were used for amplification of clonal rearrangements employing the Biomed-2 strategy (Leukemia2003; 17; 2257), followed by direct automated sequencing in ABI 377 DNA sequencer using Big-Dye terminators (Applied Biosystems, Foster City, CA). Results: All patients showed a monoclonal amplification of at least one VDJH or DJH rearrangement. VDJH monoclonal rearrangements were detected in 42/47 (89.3%) patients while DJH were observed in 20 (42.5%) patients. VH, DH and JH gene segment usage: VH3 gene segment was the most commonly represented family (76,2%) while the other gene segments were scarcely detectable, and VH5 was totally absent. In the complete VDJH rearrangements, DH6 was the family most commonly represented while DH2 (45%) and DH4 (30%) were the most common in the incomplete DJH rearrangement. Regarding JH elements, JH4 (38%) was the most represented in the complete rearrangements and JH5 (46%) in the incomplete rearrangements. Somatic hypermutation: SHM were observed in all except two of the cases (94%, 34 of 36 cases), in which the study could be performed. (median 9,38; range2.9–16.6). In the remaining clonal cases (6 cases, 14.3%) no amplification of FR1 region was obtained, also suggesting the presence of SHM. Conclusions: In this series of patients, we observed the presence of incomplete rearrangements with an incidence similar (44%) to that described in multiple myeloma. The preferential usage for determined families of genetic segments, in VDJH and in DJH, suggests the presence of positive and negative selection processes. Finally, the majority, (94 %) of the cases, presented SHM, although the presence of two patients lacking in SHM suggests a pre-follicular origin for some WM cases.

p15and p14/p16tumor suppressor genes, have been reported to be frequently inactivated by various mechanisms in haematological malignancies such us MM. Alterations of these cell cycle inhibitors in MM display a close correlation with the cell cycle and clinical outcome. We have evaluated by real time quantitative RT-PCR (RQ-PCR) the expression of the p14/p16and p15genes in purified bone marrow plasma cells (PBMPC) from MM patients in order to evaluate the possible clinical, biological and prognostic significance of these cell cycle regulators.