Lisha Ai

miR-15a and miR-16 affect the angiogenesis of multiple myeloma by targeting VEGF

Deregulated microRNAs (miRNAs) and their roles in cancer development have attracted much attention. Two miRNAs, miR-15a and miR-16, which act as putative tumor suppressor by targeting the oncogene BCL2, have been implicated in cell cycle, apoptosis and proliferation. In this study, we investigated the possible role of miR-15a/16 in the angiogenesis of multiple myeloma (MM). Using a stem-loop quantitative reverse transcription-PCR, we analyzed miR-15a/16 expressions in bone marrow samples from newly diagnosed MM patients and a panel of MM cell lines. miRNA transfection, western blotting analysis and assay of luciferase activity were used to examine whether vascular endothelial growth factor (VEGF) is the target of miR-15a/16. The functional roles of miR-15a/16 on tumorigenesis and angiogenesis were examined by in vitro angiogenesis models and in vivo tumor xenograft model. We showed that miR-15a and miR-16 were significantly underexpressed in primary MM cells as well as in MM cell lines. The aberrant expression of miR-15a/16 was detected especially in advanced stage MM. In human MM cell lines and normal plasma cells, expression of miR-15a/16 inversely correlated with the expression of VEGF-A. Western blotting combined with the luciferase reporter assay demonstrated that VEGF-A was a direct target of miR-15a/16. Ectopic overexpression of miR-15a/16 led to decreased pro-angiogenic activity of MM cells. Finally, infection of lentivirus-miR-15a or lentivirus-miR-16 resulted in significant inhibition of tumor growth and angiogenesis in nude mice. This study suggest that miR-15a/16 could play a role in the tumorigenesis of MM at least in part by modulation of angiogenesis through targeting VEGF-A.

Brain-derived neurotrophic factor is a potential osteoclast stimulating factor in multiple myeloma.

Multiple myeloma (MM) is characterized by accumulation of monoclonal plasma cells in the bone marrow and progression of lytic bone lesions. The mechanisms of enhanced bone resorption in patients with myeloma are not fully defined. We have previously identified the role of brain‐derived neurotrophic factor (BDNF) in proliferation and migration of MM cells. In our study, we investigated whether BDNF was possibly involved in MM cell‐induced osteolysis. We showed that BDNF was elevated in MM patients and the bone marrow plasma levels of BDNF positively correlated with extent of bone disease. In osteoclast formation assay, bone marrow plasma from patients with MM increased osteoclast formation and the effect was significantly blocked by neutralizing antibody to BDNF, suggesting a critical role for BDNF in osteoclast activation. Furthermore, the direct effects of recombinant BDNF on osteoclast formation and bone resorption support the potential role of BDNF in the MM bone disease. BDNF receptor TrkB was expressed by human osteoclast precursors and a Trk inhibitor K252a markedly inhibited osteoclast formation stimulated with BDNF, demonstrating that BDNF used TrkB for its effects on osteoclast. Finally, bone marrow plasma BDNF level positively correlated with macrophage inflammatory protein‐1α and receptor activator of nuclear factor‐κB ligand, two major osteoclast stimulatory factors in MM. These results support an important role for BDNF in the development of myeloma bone disease.

Inhibition of BDNF in Multiple Myeloma Blocks Osteoclastogenesis via Down-Regulated Stroma-Derived RANKL Expression Both In Vitro and In Vivo

Brain-derived neurotrophic factor (BDNF) was recently identified as a factor produced by multiple myeloma (MM) cells, which may contribute to bone resorption and disease progression in MM, though the molecular mechanism of this process is not well understood. The purpose of this study was to test the effect of BDNF on bone disease and growth of MM cells both in vitro and in vivo. Co- and triple-culture systems were implemented. The in vitro results demonstrate that BDNF augmented receptor activator of nuclear factor kappa B ligand (RANKL) expression in human bone marrow stromal cells, thus contributing to osteoclast formation. To further clarify the effect of BDNF on myeloma bone disease in vivo, ARH-77 cells were stably transfected with an antisense construct to BDNF (AS-ARH) or empty vector (EV-ARH) to test their capacity to induce MM bone disease in SCID–rab mice. Mice treated with AS-ARH cells were preserved, exhibited no radiologically identifiable lytic lesions and, unlike the controls treated with EV-ARH cells, lived longer and showed reduced tumor burden. Consistently, bones harboring AS-ARH cells showed marked reductions of RANKL expression and osteoclast density compared to the controls harboring EV-ARH cells. These results provide further support for the potential osteoclastogenic effects of BDNF, which may mediate stromal–MM cell interactions to upregulate RANKL secretion, in myeloma bone diseases.

Gene silencing of the BDNF/TrkB axis in multiple myeloma blocks bone destruction and tumor burden in vitro and in vivo

Osteolytic bone diseases are a prominent feature of multiple myeloma (MM), resulting from aberrant osteoclastic bone resorption that is uncoupled from osteoblastic bone formation. Myeloma stimulates osteoclastogenesis, which is largely dependent on an increase in receptor activator of NF‐κB ligand (RANKL) and a decrease in osteoprotegerin (OPG) within the bone marrow milieu. Recently, brain‐derived neurotrophic factor (BDNF) was identified as a MM‐derived factor that correlates with increased RANKL levels and contributes to osteolytic bone destruction in myeloma patients. Because tyrosine receptor kinase B (TrkB), the receptor of BDNF, is abundantly expressed in osteoblasts, we sought to evaluate the role of BDNF/TrkB in myeloma–osteoblast interactions and the effect of this pathway on the RANKL/OPG ratio and osteoclastogenesis. Coculture systems constructed with noncontact transwells revealed that, in vitro, MM‐derived BDNF increased RANKL and decreased OPG production in osteoblasts in a time‐ and dose‐dependent manner. These effects were completely abolished by a specific small interfering RNA for TrkB. BDNF regulates RANKL/OPG expression in osteoblasts through the TrkB/ERK pathway. To investigate the biological effects of BDNF on myeloma in vivo, a SCID‐RPMI8226 mice model was constructed using lentiviral short hairpin RNA‐transfected RPMI8226 cells. In this system, stable knockdown of BDNF in MM cells significantly restored the RANKL/OPG homostasis, inhibited osteolytic bone destruction and reduced angiogenesis and tumor burden. Our studies provide further support for the potential osteoclastogenic effects of BDNF, which mediates stroma–myeloma interactions to disrupt the balance of RANKL/OPG expression, ultimately increasing osteoclastogenesis in MM.

Once- versus twice-weekly Bortezomib induction therapy with dexamethasone in newly diagnosed multiple myeloma

SummaryIn this study, we administered a modified schedule of weekly intravenous Bortezomib at 1.6 mg/m2 with dexamethasone (BD) and compared it to the standard 1.3 mg/m2 twice-weekly BD regimen in Chinese patients with newly diagnosed multiple myeloma (MM). We assessed the difference in efficacy, safety profile and survival between the once-weekly and twice-weekly cohorts (13 vs. 24 patients). The over response rate was similar with both arms of the study, being 77% in the once-weekly schedule and 74.9% in the twice-weekly schedule (P=0.690). The median overall survival was not reached in either schedule. Also, the median progression-free survival and duration of response of the once-weekly schedule did not significantly differ from those of the twice-weekly schedule (8 months vs.10 months, P=0.545 and 6 months vs.7 months, P=0.467 respectively). Peripheral sensory neuropathy and grade 3/4 hematologic toxic effects were more frequently reported in the twice-weekly schedule than the once-weekly schedule, but there was no statistically significant difference. This preliminary experience in Chinese patients with newly diagnosed MM indicated that once-weekly infusion of Bortezomib plus dexamethasone may improve safety without affecting outcome.

Prognostic role of neutrophil–lymphocyte ratio in multiple myeloma: a dose–response meta-analysis

Background The neutrophil–lymphocyte ratio (NLR), a biomarker for systematic inflammation, has been recently identified as a prognostic factor for various types of both solid and hematologic malignancies. Our study presented here was the first meta-analysis assessing the prognostic role of NLR in multiple myeloma (MM). Methods We systematically searched PubMed, Embase, and ISI Web of Science for relevant studies. Odds ratios (ORs) or hazards ratios (HRs) with corresponding 95% CIs are pooled to estimate the association between NLR and clinicopathological parameters or survival of MM patients. Results Seven trials with 1,971 MM patients were enrolled in the meta-analysis, and the results indicated that elevated pretreatment NLR was significantly associated with advanced tumor stages (International Staging System [ISS] III vs ISS I–II: OR 2.427, 95% CI: 1.268–4.467; and Durie–Salmon III vs Durie–Salmon I–II: OR 1.738, 95% CI: 1.133–2.665). Moreover, increased NLR also predicted poorer overall survival (HR 2.084, 95% CI: 1.341–3.238) and progression-free survival (HR 1.029, 95% CI: 1.016–1.042). And two-stage dose–response meta-analysis revealed linear association between increased NLR and risk of mortality in MM patients. Conclusion We can conclude that MM patients with higher NLR are more likely to have poorer prognosis than those with lower NLR.

Subcutaneous versus Intravenous Bortezomib Administration for Multiple Myeloma Patients: a Meta-analysis

Bortezomib, the first potent therapeutic proteasome inhibitor, has been suggested as a standard care in patients with newly diagnosed and relapsed multiple myeloma (MM). However, evidence bearing on the efficacy and safety of subcutaneous (SC) versus intravenous (IV) administration of bortezomib for MM patients is controversial. Randomised controlled trials (RCTs) and observational studies were enrolled in our meta-analysis to investigate the efficacy and safety of bortezomib via SC vs. IV administration on MM patients. Sixteen trials with a total of2575 patients with MM (SC, n=1191; IV, n=1384) were included in our meta-analysis. There were no significant differences between these two arms regarding overall response rate (ORR), complete response (CR), or very good partial response (VGPR). The pooled RRs for rate of adverse events (AEs), such as thrombocytopenia and bortezomib-induced peripheral neuropathy (BIPN), were 0.79 (95% CI: 0.68-0.92) and 0.63 (95% CI: 0.51-0.79), respectively. Moreover, there was much more largely decreased incidence of grade 3 and higher thrombocytopenia and BIPN in bortezomib SC administration than IV route. In general, alternative SC administration should be considered instead of IV administration in use of bortezomib for patients with MM. Key words: bortezomib; multiple myeloma; meta-analysis; subcutaneous administrationBortezomib, the first potent therapeutic proteasome inhibitor, has been suggested as a standard care in patients with newly diagnosed and relapsed multiple myeloma (MM). However, evidence bearing on the efficacy and safety of subcutaneous (SC) versus intravenous (IV) administration of bortezomib for MM patients is controversial. Randomised controlled trials (RCTs) and observational studies were enrolled in our meta-analysis to investigate the efficacy and safety of bortezomib via SC vs. IV administration on MM patients. Sixteen trials with a total of2575 patients with MM (SC, n=1191; IV, n=1384) were included in our meta-analysis. There were no significant differences between these two arms regarding overall response rate (ORR), complete response (CR), or very good partial response (VGPR). The pooled RRs for rate of adverse events (AEs), such as thrombocytopenia and bortezomib-induced peripheral neuropathy (BIPN), were 0.79 (95% CI: 0.68-0.92) and 0.63 (95% CI: 0.51-0.79), respectively. Moreover, there was much more largely decreased incidence of grade 3 and higher thrombocytopenia and BIPN in bortezomib SC administration than IV route. In general, alternative SC administration should be considered instead of IV administration in use of bortezomib for patients with MM. Key words: bortezomib; multiple myeloma; meta-analysis; subcutaneous administration

Prognostic role of neutrophil-to-lymphocyte ratio in diffuse large B cell lymphoma patients: an updated dose–response meta-analysis

BackgroundThe neutrophil-to-lymphocyte ratio (NLR), a biomarker for systematic inflammation, has been recently identified as a prognostic factor for various types of both solid and hematologic malignancies. Here we conducted an updated dose–response meta-analysis to investigate whether NLR can be served as a prognostic biomarker in diffuse large B cell lymphoma (DLBCL).MethodsWe systematically searched PubMed, Embase, ISI Web of Science and CNKI for relevant studies. Odds ratios or hazards ratios (HRs) with corresponding 95% confidence intervals (CIs) were pooled to estimate the association between NLR and clinicopathological parameters or survival of cancer patients.ResultsEleven trials with 2515 DLBCL patients were included in the meta-analysis. The results revealed that elevated pretreatment NLR was significantly associated with elder age, advanced Ann Arbor stage, higher incidence rate of B symptoms and bone marrow involvement, and higher lactate dehydrogenase level, etc. Moreover, increased NLR also predicted poorer overall survival (HR 1.826, 95% CI 1.238–2.692) and progression-free survival/event-free survival (PFS/EFS) (HR 1.591, 95% CI 1.124–2.252). And two-stage dose–response meta-analysis revealed non-linear association between increased NLR and risk of mortality in DLBCL patients.ConclusionDLBCL patients with higher NLR are more likely to have poorer prognosis than those with lower NLR.

Prognostic role of RDW in hematological malignancies: a systematic review and meta-analysis

BackgroundRed blood cell distribution width (RDW), a biomarker for discrimination of anemia, has been recently identified as a prognostic factor in various types of cancer. Here we performed a meta-analysis in order to assess the correlation between RDW and the survival outcomes in patients with hematologic malignances.Patients/methodsWe systematically searched PubMed, Embase, and ISI Web of Science for relevant studies, to investigate the prognostic significance of RDW in hematological malignancies. Odds ratios or hazards ratios (HRs) with corresponding 95% confidence intervals (CIs) are pooled to estimate the association between RDW and clinicopathological parameters of patients with hematologic malignances.ResultsSeven trials with 1031 patients suffering from hematological malignancies were included in the meta-analysis, and the results indicated that increased pretreatment RDW predicted poor overall survival (HR = 2.35, 95% CI 1.70–3.24), poor progress-free survival (HR = 2.44, 95% CI 1.70–3.49) and poor event-free survival (EFS) (HR = 3.15, 95% CI 1.59–6.25). Furthermore, the similar results were observed in subgroup analysis stratified by cancer type, such as multiple myeloma, and diffuse large B cell lymphoma, etc.ConclusionsAs for hematologic malignances, patients with higher RDW are more likely to have poorer prognosis than those with lower RDW.