IgH translocation with undefined partners is associated with superior outcome in multiple myeloma patients.

BACKGROUND: In multiple myeloma (MM), impact of specific chromosomal translocations involving IgH (14q21 locus, including t(4;14), t(11;14), and t(14;16)) has been explored extensively. However, over 15% MM patients harboring IgH translocation with undefined partners have long been ignored. METHODS: A prospective non-randomized cohort study with a total of 715 newly-diagnosed MM cases was conducted, 13.6% of whom were t(14;undefined) positive. The whole cohort was divided into four groups: no IgH split (47.7%); t(14;undefined) (13.6%); t(11;14) (17.6%); and t(4;14) or t(14;16) group (21.1%). RESULTS: Median OS for the four groups was 84.2, not reached (NR), 58.7, and 44.2 months, respectively, with P values for t(14;undefined) vs no IgH split, t(11;14), and t(4;14)/t(14;16) groups of 0.197, 0.022, and 0.001, respectively. In bortezomib-based group, the survival advantage gained by t(14;undefined) group was much more significant compared to t(11;14) and t(4;14)/t(14;16) groups. Importantly, t(14;undefined) turned out to be an independent predictive factor for longer OS of MM patients in multivariate analysis, especially in the context of bortezomib treatment. Similar results were also observed in the PUMCH external validation cohort. CONCLUSION: Collectively, our data confirmed and externally validated the favorable prognosis of the t(14;undefined) groups, especially in the era of novel agents.

The ceramide pathway is involved in the survival, apoptosis and exosome functions of human multiple myeloma cells in vitro.

Multiple myeloma (MM) is characterized by the clonal proliferation of malignant plasma cells and refractoriness to traditional therapies. It has been shown that exosomes are involved in modulating the progression and the metastasis of cancers through microRNAs (miRs). Ceramide is a type of sphingolipid; the ceramide pathway of exosomal secretion has been shown to affect the apoptosis of cancer cells. But the role of this pathway in MM cell function, exosome function and miR regulation remains unknown. In this study, we showed that C6 ceramide (an exogenous ceramide supplement, 1.25-40 µmol/L) dose-dependently inhibited the proliferation and promoted the apoptosis in human MM OPM2 cell line, which were associated with elevated caspase 3/9 and PARP cleavage. We also found that C6 ceramide (5-20 µmol/L) dose-dependently stimulated exosome secretion and increased exosomal levels of tumor-suppressive miRs (miR 202, miR 16, miR 29b and miR 15a). Of note, exosomes from C6 ceramide-treated OPM2 cells could influence the proliferation and apoptosis of the recipient OPM2 cells, which correlated with increased tumor-suppressive exosomal miRs. In contrast, GW4869 (a ceramide inhibitor, 5-20 µmol/L) exerted the opposite effects on the regulation of MM function, exosome secretion and miR levels in MM exosomes. However, exosomes from GW4869-treated OPM2 cells had no effect on these miRs and the survival of targeted OPM2 cells. Taken together, our findings reveal that the ceramide pathway modulates MM survival, probably directly via the caspase pathway and indirectly via exosomal miR mechanisms.

[Expression of 11ß-hydroxysteroid dehydrogenase type 2 in lymphoblastic cells and its relationship with glucocorticoid sensitivity].

This study was aimed to explore the expression of 11ß-hydroxysteroid dehydrogenase type 2 (11ß-HSD2) in 3 different lymphoblastic cell lines with relation to their glucocorticoid (GC) sensitivity. The 11ß-HSD2 expressions in acute lymphoblastic leukemia Jurkat cells, lymphoma Daudi and Raji cells, and peripheral blood T cells of a healthy volunteer were analyzed by real time PCR and Western blot. Glucocorticoid (GC)-induced apoptosis in 3 different cell lines was detected by flow cytometry. Cell growth in Jurkat cells treated with cortisol was analyzed by trypan blue dye exclusion. Flow cytometry was performed to observe GC-induced apoptosis in Jurkat cells treated by combination of GC with 11ß-HSD2 inhibition 18ß-glycyrrhetinic acid (18ß-GA). The results demonstrated that 11ß-HSD2 highly expressed in Jurkat cells, but not in Daudi, Raji cells and normal blood T cells. Compared to Daudi and Raji cells, Jurkat cells were more resistant to GC-induced apoptosis. Furthermore, the inhibition of 11ß-HSD2 by 18ß-GA resulted in increased cellular sensitivity to GC as shown by elevated induction of apoptosis. it is concluded that 11ß-HSD2 is at least partly responsible for GC resistance in Jurkat cells. 11ß-HSD2 may be a potential target for reduction of GC-resistance in therapeutic applications.

Gene expression profiling defines a high-risk entity of multiple myeloma.

Multiple myeloma (MM) is the second most common hematological malignancy and remains incurable. The marked variation in survival of patients with symptomatic myeloma ranging from few months to more than 15 years can be explained by differences in tumor mass, proliferative activity and, more recently, by cytogenetic and molecular genetic characteristics of the myeloma clone. Oligonucleotide microarray-based gene expression analysis was applied to CD138-enriched plasma cells from newly diagnosed patients with symptomatic or progressive multiple myeloma treated with melphalan-based high-dose therapy. Here we discuss recent progress made in the development of molecular-based diagnostics and prognostics for MM from Myeloma Institute for Research and Therapy of University Arkansas for Medical Sciences, where we treat more patients with myeloma than anywhere else in the world. Seven distinct entities of myeloma were elucidated by genomic profiling. Expression extremes of 70 genes from a high-risk signature profile,30% of which were derived from chromosome 1, were strongly linked to disease-related survival. CKS1B located on chromosome 1q21, responsible for promoting cell cycle progression by inducing the degradation of p27Kip1, represented a strong candidate gene related to rapid patient death and was studied in detail. The data suggest that CKS1B influences myeloma cell growth and survival through SKP2j and P27(Kip1) -dependent and independent mechanisms and that therapeutic strategies aimed at abolishing CKS1B function may hold promise for the treatment of high-risk disease for which effective therapies are currently lacking.

Analysis and Molecular Cloning of Differentially Expressing Genes in Nasopharyngeal Carcinoma.

In order to further examine expression of cDNA fragments isolated by cDNA representational difference analysis(cDNA RDA) in nasopharyngeal carcinoma(NPC) biopsies and to clone those deregulated genes associated with NPC, RT-PCR and Northern blot were used to identify the differentially expressed cDNA fragments in NPC biopsies and confirm the transcript length of those genes, then a full-length cDNA sequences was cloned and its product was analyzed by bioinformatics. The results showed that AF091521, AF091520, AF152605 and AF091517 cDNA sequences had distinct expression difference between primary cultural normal nasopharyngeal epithelial cell and NPC biopsies, and AF091521, AF091517 genes all had two transcripts whose sizes were 1.5, 2.3 and 1.1, 1.4 kb respectively, while AF091520 and AF152605 gene expressed one transcript only, respectively, whose sizes were 1.6 and 2.2 kb. An AF091517 EST gene, named as NAG11, (GenBank accession number AF170307) was isolated by sequencing one EST clone, which encoded a transmembrane protein of 88 amino acid including three protein ATP-binding regions, two protein kinase C phosphorylation sites and two N-myristoylation sites. So it is further demonstrated that NPC is a disease with multiple gene alterations NAG11 gene is a candidate of putative tumor suppressor genes associated with NPC, whose down-expression may be involved in the development of NPC and NAG11 gene product may play a role in the transmembrane transport of ATP.