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Background The antimyeloma agent bortezomib functions as an inhibitor of nuclear factor (NF)–κB. Although NF-κB inhibition is predicted to affect osteoclast function, preclinical and clinical studies have primarily reported an effect on osteoblasts. Patients and Methods We examined parameters of bone turnover prospectively in patients with multiple myeloma treated with bortezomib before and after autologous transplantation. Thirty-nine patients received 2 cycles of bortezomib on days 1, 4, 8, and 11 of a 21-day cycle. After high-dose melphalan with autologous stem cell transplantation, bortezomib 1.3 mg/m 2 on days 1, 8, 15, and 22 of a 5-week cycle was administered as maintenance therapy. Results During posttransplantation bortezomib, decreases in the urinary excretion of collagen N-telopeptide indicated that bortezomib suppresses osteoclast function. Conclusion The effects on osteoclasts occurred in the absence of bisphosphonate treatment and independently of changes in monoclonal protein levels. Further studies exploring the role of bortezomib as a bone protective agent could be warranted.

We present evidence that the 5-hydroxytryptamine(1A) (5-HT(1A)) receptor antagonist, N-{2-[4-(2-methoxyphenyl)-1-piperazinyl]-ethyl}-N-(2-pyridinyl)cyclohexanecarboxamide (WAY-100635), can induce receptor internalization in a human (h)5-HT(1A) receptor Chinese hamster ovary (CHO-K1) cell system. Exposure of h5-HT(1A) CHO cells to WAY-100635 decreased the cell-surface h5-HT(1A) receptor density in a way that was both time (24-72 h) and concentration (1-100 nm) dependent.[(3)H]WAY-100635 and [(3)H]8-hydroxy-dipropylaminotetralin ([(3)H]8-OH-DPAT) saturation analyses demonstrated a significant reduction (50-60%) in total h5-HT(1A) receptor number in the WAY-100635-treated (100 nm; 72 h) compared with control cells. In WAY-100635-treated cells, the 8-OH-DPAT-mediated inhibition of forskolin (FSK)-stimulated cAMP accumulation was right-shifted and the maximal inhibitory response of 8-OH-DPAT was impaired compared with control cells. Similar results were obtained for 8-OH-DPAT-mediated Ca(2+) mobilization after WAY-100635 treatment. h5-HT(1A) receptors labeled with [(3)H]WAY-100635, as well as [(3)H]4-(2'-Methoxy)-phenyl-1-[2'-(N-2''-pyridinyl)-p-fluorobenzamido]ethyl-piperazine (MPPF), exhibited a time-dependent rate of cellular internalization that was blocked by endocytotic suppressors and was pertussis-toxin insensitive. In contrast, quantitative autoradiographic studies demonstrated that chronic treatment of rats with WAY-100635 for two weeks produced a region-specific increase in the 5-HT(1A) receptor density. In conclusion, prolonged exposure of an h5-HT(1A) cell-based system to the 5-HT(1A) antagonist, WAY-100635, induced a paradoxical internalization of cell surface receptor resulting in depressed functional activity. This suggests that an antagonist can influence 5-HT(1A) receptor recycling in vitro differently to in vivo regulatory conditions.

WAY-161503 ((4a R )-8,9-dichloro-2,3,4,4a-tetrahydro-1 H -pyrazino[1,2-a]quinoxalin-5(6 H )-one), a 5-HT 2B/C receptor agonist, was characterized in vitro using stable Chinese hamster ovary cell lines expressing each of the human 5-HT 2 receptors and in vivo in animal models of obesity. WAY-161503 displaced both agonist ([ 125 I]2,5-dimethoxy-4-iodoamphetamine (DOI)) and antagonist ([ 3 H]mesulergine) radioligand binding to the human 5-HT 2C receptor with derived Ki values of 3.3 ± 0.9 and 32 ± 6 nM, respectively. Relative to 5-HT 2C receptor binding, WAY-161503 was approximately 6-fold less potent at human 5-HT 2A receptors ([ 125 I]DOI) with a derived Ki value of 18 nM and 20-fold less potent at human 5-HT 2B receptors ([ 3 H]5-HT) with a derived Ki value of 60 nM. In functional studies, WAY-161503 was a full agonist in stimulating 5-HT 2C -receptor-coupled [ 3 H]inositol phosphate (IP) formation and calcium mobilization with EC 50 values of 8.5 nM and 0.8 nM, respectively. WAY-161503 was also a 5-HT 2B agonist (EC 50 s of 6.9 and 1.8 nM for IP and calcium, respectively). In IP studies, WAY-161503 was a weak 5-HT 2A partial agonist (EC 50 , 802 nM) yet potently stimulated calcium mobilization (EC 50 , 7 nM) in 5-HT 2A receptor-expressing cells. Functionally, WAY-161503 also stimulated the phospholipase A 2 -coupled arachidonic acid release in 5-HT 2C receptor expressing cells albeit with lower potency (EC 50 , 38 nM) and efficacy (Emax, 77%) compared with activation of the PLC pathway. In vivo, WAY-161503 produced dose-dependent decreases in 2-h food intake in 24 h fasted normal Sprague–Dawley rats, diet-induced obese mice, and obese Zuker rats with ED 50 values of 1.9 mg/kg, 6.8 mg/kg, and 0.73 mg/kg, respectively. The reduction in food intake in normal Sprague–Dawley rats was reversed by administration of the 5-HT 2C receptor antagonist SB-242084. Following chronic administration (10 days) in growing Sprague–Dawley rats, WAY-161503 decreased food intake and attenuated body weight gain. Finally, following chronic administration (15 days) of WAY-161503 to obese Zuker rats, the rats maintained a 30% decrease in food intake over the 15-day period combined with a 25 g decrease in body weight relative to vehicle-treated controls demonstrating a lack of tolerance to its anorectic effects.

The pancreatic adenocarcinoma genome harbors multiple amplifications and deletions, pointing to the existence of numerous oncogenes and tumor suppressor genes driving the genesis and progression of this lethal cancer. Here, array comparative genomic hybridization on a cDNA microarray platform and informatics tools have been used to define the copy number alterations in a panel of 24 pancreatic adenocarcinoma cell lines and 13 primary tumor specimens. This high-resolution genomic analysis has identified all known regional gains and losses as well as many previously uncharacterized highly recurrent copy number alterations. A systematic prioritization scheme has selected 64 focal minimal common regions (MCRs) of recurrent copy number change. These MCRs possess a median size of 2.7 megabases (Mb), with 21 (33%) MCRs spanning 1 Mb or less (median of 0.33 Mb) and possessing an average of 15 annotated genes. Furthermore, complementary expression profile analysis of a significant fraction of the genes residing within these 64 prioritized MCRs has enabled the identification of a subset of candidates with statistically significant association between gene dosage and mRNA expression. Thus, the integration of DNA and RNA profiles provides a highly productive entry point for the discovery of genes involved in the pathogenesis of pancreatic adenocarcinoma.

Gene expression of osteopontin (OPN) has been investigated in mice by application of laser capture microdissection (LCM) and reverse transcriptase-polymerase chain reaction (RT-PCR) analysis. LCM permits individual cells to be isolated ("captured") from tissue sections for molecular analyses. In this study, chondrocytes were captured from growth plate zones in frozen sections of tibiae from 1-11-day-old postnatal mice. RNA was extracted from cells, DNAse-treated, and reverse-transcribed. cDNA was amplified by PCR and OPN mRNA was revealed on agarose gels. Whole cartilage and brain (a positive control) from the same animals also were examined. Reactions containing no RT were negative controls, and 18S rRNA standardized expressed message from captured cells. RT-PCR analysis of laser-captured whole cartilage showed a general qualitative loss of OPN mRNA as animal age increased. Youngest mice gave equivalent OPN expression over all laser-microdissected cartilage zones. For 7-11 day-old mice, OPN expression was qualitatively greatest in resting and lowest in hypertrophic regions of cartilage. Expression of OPN correlated with mineral in the tissue suggests that OPN functionally may inhibit normal vertebrate growth plate mineralization, and its loss with increasing tissue maturation appears permissive to mineral development.

Growth of InAs epitaxial layers on GaAs (001 ) by migration-enhanced epitaxy (MEE) and molecular beam epitaxy (MBE) has been studied. Reflection high-energy-electron diffraction (RHEED) patterns were studied, and persistent RHEED intensity oscillations were observed during MEE growth of InAs. The dependence of RHEED oscillation on MEE growth parameters is discussed. InAs layers grown by MEE at low substrate temperature exhibit comparable quality as MBE layers grown at higher substrate temperature.

Multiple Myeloma (MM) is characterized by a clonal proliferation of abnormal plasma cells in the bone marrow and is among the most frequent and lethal hematological diseases. In spite of significant effort towards the identification of the molecular events leading to this malignancy, the genetic alterations responsible for the pathogenesis of this disease remain poorly understood. Regional copy number alterations (CNAs) in cancer genomes have been among the most informative structural changes in cancer and have led to the discovery of many oncogenes and tumor supressor genes. Using array comparative genomic hybridization (array-CGH) and expression microarray technologies we have analyzed a large collection of cell lines and clinically annotated primary tumors. This high-resolution genomic analysis has identified all previously reported regional gains and losses as well as many novel highly recurrent genetic loci with potential biological and clinical relevance. In particular, we have identified an amplification at chromosome 1q21 as one of the most recurrent genetic changes in cell lines and in a subgroup of primary tumors. This chromosomal change has been previously implicated with disease progression. Analysis across several cell lines has allowed the identification of a Minimal Common Region (MCRs) of amplification at 1q21. Correlation between DNA copy number changes and expression profiling data has identified a limited set of candidate genes within this MCR that are amplified and overexpressed. Using shRNAi technology we have identified BCL-9 as a candidate gene residing at the 1q21 MCR. In vitro and in vivo functional data about the role of BL-9 will be presented. These data will provide critical understanding on the diverse pathways leading to Multiple Myeloma progression.