[Long-term follow-up of multiple myeloma after autologous hematopoietic stem cell transplantation: a single center results]

目的

评价诱导治疗联合自体周血造血干细胞移植（ASCT）治疗、移植后巩固维持治疗的整体方案治疗多发性骨髓瘤（MM）患者的有效性和长期随访结果。

方法

回顾性分析2005年1月1日至2016年2月1日接受整体方案治疗的144例MM患者资料，总结其长期随访结果，分析移植前疗效、移植后缓解深度，以及早期移植、晚期移植、不同预后分期系统等因素对患者生存的影响。

结果

144例患者中获得部分缓解（PR）以上治疗反应率为89.4%[完全缓解（CR）率64.1%]。中位随访47（6~121）个月，患者中位总体生存（OS）和无进展生存（PFS）时间分别为120.9和56.9个月；早期和晚期移植组患者的中位OS分别为120.9和50.1个月，中位PFS时间分别为60.2和16.7个月（P值均<0.001）。127例可进行修订的国际分期系统（R-ISS）分期患者中，Ⅰ期（43例）、Ⅱ期（64例）、Ⅲ期（20例）患者的中位OS时间分别为120.9、88.4、35.6个月，组间差异有统计学意义（P=0.000）。对早期和晚期移植组患者进行亚组生存分析，R-ISS Ⅲ期患者中位OS时间差异有统计学意义（35.6个月对15.8个月，P=0.031）；两组患者各期中位PFS时间差异均有统计学意义（Ⅰ期：72.1个月对18.9个月；Ⅱ期：53.4个月对16.7个月；Ⅲ期：28.5对5.9个月，P值分别为0.000、0.012、0.001）。多因素分析结果显示R-ISS Ⅲ期是影响患者OS的危险因素（HR=8.486，95%CI 2.549~28.255，P=0.003），移植后未获得CR是影响患者PFS的危险因素（HR=2.412，95%CI 1.364~4.266，P=0.002）。

结论

以新药为基础的化疗联合ASCT的整体治疗方案对适合移植的MM患者是有效的，可进一步提高缓解率和缓解深度，延长患者的PFS和OS时间。早期较晚期移植可明显延长患者的OS和PFS时间。R-ISS分期和移植前疗效是影响患者生存的预后因素。

[Outcomes of lenalidomide-based treatment for 57 patients of relapsed or refractory multiple myeloma]

目的

探讨来那度胺（商品名瑞复美）为基础的化疗方案在复发或难治性多发性骨髓瘤（MM）患者中的疗效及安全性。

方法

回顾性分析2013年6月至2016年2月收治的57例应用来那度胺为基础的方案治疗的复发或难治性MM患者资料。

结果

①国际分期系统（ISS）Ⅲ期患者比例为60.4%，修改的国际分期系统（R-ISS）Ⅲ期患者比例为37.9%，53.3%的患者存在高危遗传学异常。②患者应用来那度胺中位疗程为6（1~32）个。治疗的总体缓解率（ORR）为58.9%（33/56），其中完全缓解率为8.9%，非常好的部分缓解率为19.8%，部分缓解（PR）率为30.4%。此外有10.7%（6/56）的患者达到微小缓解，临床获益率69.6%。前期接受一线以上治疗、既往沙利度胺耐药及R-ISS Ⅲ期患者ORR较低。③中位随访27个月，患者中位无进展生存（PFS）时间8个月，中位达PR时间2个月，中位缓解持续时间（DOR）8个月，中位总体生存（OS）时间19个月。单因素分析中，染色体核型异常、R-ISS分期Ⅲ期、疗效未达PR及以上是影响患者PFS和OS的不良因素。多因素分析显示，染色体核型异常、R-ISS分期Ⅲ期具有独立预后意义。④安全性分析显示，最常见的3/4级非血液学不良反应为感染（17.5%）、皮疹（1.8%）、血栓（1.8%）。最常见的3/4级血液学不良反应为中性粒细胞减少（7.0%）和血小板减少（3.5%）。共有3例（5.3%）患者因不良反应停药。共观察到第二肿瘤2例（3.5%）。

结论

来那度胺为基础的化疗方案在复发或难治性MM患者中有效率高、耐受性良好。预后因素分析显示，在这一患者群体中染色体核型异常、R-ISS分期Ⅲ期是独立预后不良因素。

Influence of VEGF/BMP-2 on the proliferation and osteogenetic differentiation of rat bone mesenchymal stem cells on PLGA/gelatin composite scaffold

OBJECTIVE

To investigate the influence of VEGF/BMP-2 on the proliferation and osteogenic differentiation of rat bone mesenchymal stem cells BMSCs) on PLGA/gelatin composite scaffold.

MATERIALS AND METHODS

Randomly-oriented nanofibers with different ratios of Poly Lactic-co-Glycolic Acid (PLGA)/gelatin were produced through electrospinning. The mixture of nanofibers and BMSCs was pipetted onto the surface of the scaffolds, and BMSCs/PLGA/gelatin composite was obtained. The surface morphology, chemical structure, hydrophilicity and mechanical property of PLGA/gelatin nanofibers were revealed by scanning electron microscope. In vitro release kinetics of bone morphogenetic protein (BMP-2) and vascular endothelial growth factor (VEGF) were studied using ELISA kits. The cell adhesion, growth and proliferation of BMSCs on scaffolds were observed by scanning electron microscopy. The CCK-8 assay was used to evaluate the effects of VEGF/BMP-2 slow release system on the proliferation of BMSCs on scaffolds. RT-PCR was used to examine the activities of alkaline phosphatase (ALP), runt-related transcription factor 2 (RUNX-2), and osteocalcin (OCN).

RESULTS

In each group of cells in the in-vitro experiment, through electron microscope scanning, fiber scaffolds were interconnected three-dimensional reticular structure, BMSCs firmly attached to the fiber surface and internal stent, cells experienced a long spindle, polygon change, and branch-like protrusions on the cell surface were connected. Under the electron microscope, cell proliferation curve and osteogenesis markers (ALP, RUNX-2, OCN) expression in the dual factor group on cell adhesion, proliferation and differentiation were much better than those of blank control group and single factor groups.

CONCLUSIONS

In the successfully constructed gelatin/PLGA nanofiber scaffold, VEGF and BMP-2 can be sequentially released, during which VEGF and BMP-2 can promote the adhesion, proliferation, and differentiation of BMSCs.

Epigenetic silencing of miR-137 induces drug resistance and chromosomal instability by targeting AURKA in multiple myeloma

Multiple myeloma (MM) is the second most prevalent hematologic malignancy. Aberrant microRNAs (miRNAs) expression has been shown to be involved in the pathogenesis of MM. In this study, we further demonstrated that miR-137 was significantly downregulated in MM and negatively correlated with clinical prognosis. Moreover, we described the epigenetic regulation of miR-137 and its association with progression-free survival in MM patients. Furthermore, overexpression of miR-137 in MM cell line (miR-137 OE) increased its sensitivity to bortezomib and eprirubicin in vitro. Also, some high-risk genetic abnormalities in MM, including deletion of chromosome 1p22.2, 14q or 17p13, and gain of chromosome 1p22.2 were detected in NCI-H929 empty vector (NCI-H929 EV) treated cells but not in the NCI-H929 miR-137 overexpression (NCI-H929 miR-137 OE) cells. Luciferase reporter assays demonstrated that miR-137 targeted AURKA. Ectopic expression of miR-137 strongly reduced the expression of AURKA and p-ATM/Chk2 in MM cells, and increased the expression of p53, and p21. Importantly, miR-137 overexpression together with bortezomib treatment significantly inhibited tumor growth in MM xenograft model. Taken together, this study demonstrates that miR-137 is epigenetically silenced in MM, and overexpression of miR-137 could reduce drug resistance and overcome chromosomal instability of the MM cells via affecting the apoptosis and DNA damage pathways.

Optimization and Control of Agent-Based Models in Biology: A Perspective

Agent-based models (ABMs) have become an increasingly important mode of inquiry for the life sciences. They are particularly valuable for systems that are not understood well enough to build an equation-based model. These advantages, however, are counterbalanced by the difficulty of analyzing and using ABMs, due to the lack of the type of mathematical tools available for more traditional models, which leaves simulation as the primary approach. As models become large, simulation becomes challenging. This paper proposes a novel approach to two mathematical aspects of ABMs, optimization and control, and it presents a few first steps outlining how one might carry out this approach. Rather than viewing the ABM as a model, it is to be viewed as a surrogate for the actual system. For a given optimization or control problem (which may change over time), the surrogate system is modeled instead, using data from the ABM and a modeling framework for which ready-made mathematical tools exist, such as differential equations, or for which control strategies can explored more easily. Once the optimization problem is solved for the model of the surrogate, it is then lifted to the surrogate and tested. The final step is to lift the optimization solution from the surrogate system to the actual system. This program is illustrated with published work, using two relatively simple ABMs as a demonstration, Sugarscape and a consumer-resource ABM. Specific techniques discussed include dimension reduction and approximation of an ABM by difference equations as well systems of PDEs, related to certain specific control objectives. This demonstration illustrates the very challenging mathematical problems that need to be solved before this approach can be realistically applied to complex and large ABMs, current and future. The paper outlines a research program to address them.

The protective effects of bone morphogenetic protein-7 against epithelial injury and matrix metalloproteases upregulation induced by silica in vitro

OBJECTIVE

We investigate the effects of bone morphogenetic protein-7 (BMP-7) on models with silica-induced and macrophage-mediated fibrosis and its possible mechanisms in vitro.

METHODS

Rat alveolar II epithelial (RLE-6TN) cells were incubated with the supernatant of mouse macrophage-like cells (RAW264.7) and treated with 0, 25, 50, and 100 μg/mL silica. Using Western blotting, the epithelial markers (surfactant proteins-C and E-cadherin) and the mesenchymal markers (fibronectin (FN) and viminten (Vim)) were detected. After neutralizing the BMP-7, the progress of fibrosis was assessed by the content of hydroxyproline (Hyp) and collagen I, III protein levels as well as the Smad signaling pathway proteins, including phosphorylated Smad1/5(P-Smad1/5) and phosphorylated Smad2/3(P-Smad2/3). Collagen I was also identified by immunofluorescence and pretreated with SB-431542, LDN-193189, or anti-BMP-7-neutralizing antibody. In addition, the levels of matrix metalloproteinase-2 (MMP-2) and MMP-9 were detected using Western blotting.

RESULTS

The model of RLE-6TN cells was established successfully, the expressions of Vim, FN, MMP-2, and MMP-9 were upregulated, while the concentration of silica is increased. Neutralizing BMP-7 stimulated the decrease of P-Smad1/5 and the increase of P-Smad2/3, as well as the collagen I, collagen III, FN, and Hyp via Smad signaling pathway. Furthermore, pretreated with LDN-193189 or anti-BMP-7-neutralizing antibody, the expression of collagen I was increased, yet it was decreased with SB-431542 intervention.

CONCLUSION

The activated BMP/Smad and suppressed transforming growth factor-β/Smad pathways could suppress silica-induced fibrosis via a MMP-dependent mechanism. BMP-7 is expected to be the optimized strategy of delaying the interstitial changes.

SAR650984 directly induces multiple myeloma cell death via lysosomal-associated and apoptotic pathways, which is further enhanced by pomalidomide

The anti-CD38 monoclonal antibody SAR650984 (SAR) is showing promising clinical activity in treatment of relapsed and refractory multiple myeloma (MM). Besides effector-mediated antibody-dependent cellular cytotoxicity and complement-mediated cytotoxicity, we here define molecular mechanisms of SAR-directed MM cell death and enhanced anti-MM activity triggered by SAR with Pomalidomide (Pom). Without Fc-cross-linking agents or effector cells, SAR specifically induces homotypic aggregation (HA)-associated cell death in MM cells dependent on the level of cell surface CD38 expression, actin cytoskeleton and membrane lipid raft. SAR and its F(ab)'2 fragments trigger caspase 3/7-dependent apoptosis in MM cells highly expressing CD38, even with p53 mutation. Importantly, SAR specifically induces lysosome-dependent cell death (LCD) by enlarging lysosomes and increasing lysosomal membrane permeabilization associated with leakage of cathepsin B and LAMP-1, regardless of the presence of interleukin-6 or bone marrow stromal cells. Conversely, the lysosomal vacuolar H+-ATPase inhibitor blocks SAR-induced LCD. SAR further upregulates reactive oxygen species. Pom enhances SAR-induced direct and indirect killing even in MM cells resistant to Pom/Len. Taken together, SAR is the first therapeutic monoclonal antibody mediating direct cytotoxicity against MM cells via multiple mechanisms of action. Our data show that Pom augments both direct and effector cell-mediated MM cytotoxicity of SAR, providing the framework for combination clinical trials.

Expression of recombinant BMP-7 gene increased ossification activity in the rabbit bone mesenchymal stem cells

OBJECTIVE

The mesenchymal stem cells (MSCs), which were distributed in the bone marrow stroma, become ideal progenitor cells in bone tissue engineering because of their convenient isolation, small injury when obtained, and strong osteogenic capacity. The osteogenic differentiation of MSCs, which is indicated by the increased alkaline phosphatase (ALP) activity and the enhanced accumulation of collagen, could be induced by a strong osteogenic capacity biological factor termed bone morphogenetic protein-7 (BMP-7). Although the chemically synthesized BMP-7 was widely applied to study the osteogenic differentiation of MSCs, transferring and expressing BMP-7 gene in target cells is more desirable, especially for gene therapy, given the advantages and convenience on the stable expression of BMP-7. The aim of this study was to determine whether recombinant BMP-7-expressing MSCs would induce bone formation in vitro.

MATERIALS AND METHODS

BMP-7 gene was cloned from human placental tissue to construct a recombinant eukaryotic expression plasmid carrying BMP-7 gene by conjugating with eukaryotic expression vector pcDNA3.1. MSCs were isolated from rabbit bone marrow and cultured in vitro. Then they were divided into 3 groups: pcDNA3.1-BMP-7-transfected, pcDNA3.1-transfected, and untransfected. Human healthy fresh placental tissue was provided by the Department of Gynaecology and Obstetrics, Second Affiliated Hospital of Harbin Medical University. Written informed consent was obtained from the women. One healthy male New Zealand rabbit was provided by the Laboratory Animal Center, Harbin Medical University.

RESULTS

A significant increase of ALP activity was detected in the supernatant of pcDNA3.1-BMP-7 transfected MSCs, and the enhanced collagen accumulation, which was inferred by the increased hydroxyproline content and RT-PCR.

CONCLUSIONS

These results implied that BMP-7 gene was expressed in MSCs sufficiently and was involved in inducing differentiation of MSCs into osteoblast.

The accuracy of circulating microRNA-21 in the diagnosis of colorectal cancer: a systematic review and meta-analysis

AIM

The accuracy and clinical value of circulating microRNA-21 (miR-21) were assessed as a novel diagnostic biomarker of colorectal cancer (CRC).

METHOD

Medline/PubMed, EMBASE, the Cochrane Library databases and grey literature (Google scholar; British Library) were searched up to 29 September 2014 for eligible studies of the association between blood-based miR-21 and a diagnosis of CRC. Quality Assessment of Diagnostic Accuracy Studies (QUADAS) was employed to assess the quality of the included studies by two investigators. Stata12.0 and Meta-DiSc1.4 software were applied to test the heterogeneity using Cochran's Q test and I(2) statistics and to perform the meta-analysis.

RESULTS

Seven studies with 676 CRC patients and 417 controls were included in the meta-analysis. All were of high quality (QUADAS scores 12 or 13). For miR-21, the pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and diagnostic odds ratio to predict CRC were 75% [95% confidence interval (CI) 63-83%], 84% (95% CI 79-87%), 4.61 (95% CI 3.38-6.29), 0.30 (95% CI 0.20-0.46) and 16.89 (95% CI 7.56-37.73) after using a random-effects model analysis. The area under the summary receiver operating characteristic curve was 0.86 (95% CI 0.83-0.89).

CONCLUSION

The results suggest that circulating miR-21 is a biomarker with moderate sensitivity and specificity for CRC.

Three novel single nucleotide polymorphisms of the 3-hydroxy-3-methylglutaryl coenzyme A reductase gene associated with egg-production in chicken

Different single-strand conformation polymorphism (SSCP) patterns of the 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR) gene amplified by six pairs of primers were sequenced. Comparisons among the six nucleotide sequences of three genotypes revealed three base substitutions (G-789-A, C-937-G, and A-2316-C) in the HMGCR gene. The genotypes of single nucleotide polymorphism 1 (SNP1) and SNP3 were significantly associated with the number of eggs (P < 0.01), and the different genotypes of SNP2 did not significantly influence the number of eggs. The genotypes of all three SNPs were not related to the hatching rate of fertilized eggs (P > 0.05). Of the three SNPs of the HMGCR gene, those genotypes with lower plasma very low-density lipoprotein (VLDL) concentrations had higher egg production. The 300-day egg production of the six studied haplotypes showed three levels (P < 0.01). The ADE and ACE haplotypes showed lower egg production than the other haplotypes. The ADE haplotype had the highest plasma VLDL concentration, and the ACE haplotype had the lowest plasma VLDL concentration. We concluded that specific variants of the HMGCR gene are associated with chicken egg production, and haplotypes with higher and lower plasma VLDL concentrations showed lower egg production than other haplotypes.

Population pharmacokinetics of rifampin in the treatment of Mycobacterium tuberculosis in Asian elephants

The objective of this study was to develop a population pharmacokinetic model for rifampin in elephants. Rifampin concentration data from three sources were pooled to provide a total of 233 oral concentrations from 37 Asian elephants. The population pharmacokinetic models were created using Monolix (version 4.2). Simulations were conducted using ModelRisk. We examined the influence of age, food, sex, and weight as model covariates. We further optimized the dosing of rifampin based upon simulations using the population pharmacokinetic model. Rifampin pharmacokinetics were best described by a one-compartment open model including first-order absorption with a lag time and first-order elimination. Body weight was a significant covariate for volume of distribution, and food intake was a significant covariate for lag time. The median Cmax of 6.07 μg/mL was below the target range of 8-24 μg/mL. Monte Carlo simulations predicted the highest treatable MIC of 0.25 μg/mL with the current initial dosing recommendation of 10 mg/kg, based upon a previously published target AUC0-24/MIC > 271 (fAUC > 41). Simulations from the population model indicate that the current dose of 10 mg/kg may be adequate for MICs up to 0.25 μg/mL. While the targeted AUC/MIC may be adequate for most MICs, the median Cmax for all elephants is below the human and elephant targeted ranges.

Expressing osteogenic growth peptide in the rabbit bone mesenchymal stem cells increased alkaline phosphatase activity and enhanced the collagen accumulation

OBJECTIVES

The multipotent mesenchymal stem cells (MSCs) were distributed in the bone marrow stroma, and could generate all of the different skeletal cell lineages. The osteogenic differentiation of MSCs, which is indicated by the increased alkaline phosphatase (ALP) activity and the enhanced accumulation of collagen, could be induced by a tetradecapeptide termed osteogenic growth peptide (OGP). It has been hypothesized that the OGP induces the osteogenic differentiation of MSCs probably through regulating the fibroblast growth factor signaling pathways. Although the chemically synthesized OGP was widely applied to study the osteogenic differentiation of MSCs, transferring and expressing OGP gene in target cells is more desirable, especially for gene therapy, given the advantages and convenience on the stable expression of OGP.

MATERIALS AND METHODS

In this study, we attempt to test the effect of OGP gene transfection; we constructed a eukaryotic expression vector, pcDNA3.1-OGP, which contained the OGP-coding DNA fragment. Subsequently, the vector was transfected into the rabbit MSCs.

RESULTS

A significant increase of ALP activity was detected in the supernatant of pcDNA3.1-OGP transfected MSCs, and the enhanced collagen accumulation, which was inferred by the increased hydroxyproline content and RT-PCR.

CONCLUSIONS

These results implied that transfecting the OGP-expressing vectors into MSCs might induce the osteogenic differentiation of MSCs.

Abstract P5-10-02: Investigating the response and adaptation of estrogen receptor (ER)+ tumors in response to decreased estrogen availability using an agent-based model of the mammary epithelium

Introduction: Breast tumors consist of heterogenous cell populations with dominant features that can change over time. The development of resistance to previously effective therapies is an example of tumor evolution in response to selective pressure, where the differential composition of cells within a tumor may predispose to identifiable patterns of tumor growth and progression. We employ a previously developed computational model of ductal epithelial dynamics (the Duct Epithelial Agent Based Model or DEABM), able to reproduce known rates of tumorigenesis in both wild-type and BRCA1 populations, to investigate the putative population dynamics of ER+ tumors in response to decreased estrogen availability (DEA).

Methods: The DEABM is composed of computational agents representing individual cells (luminal and myoepithelial cells, their progenitor cells and fibroblasts) behaving based on rules established from published cellular and molecular mechanisms. Cells implement DNA damage/repair, cell division in response to estrogen/local growth factors, and apoptosis. Unrepaired DNA damage impacts genomic integrity, including eight representative oncogenes and tumor suppressors affecting critical pathways previously implicated in breast cancer (BRCA1, P53, E-cadherin, RUNX3, Myc, TGF-beta, MMP-3 and Telomerase). ER+ tumors were generated in 40 year simulations of wild-type and BRCA1 populations and subjected to DEA (90% reduction in estrogen effect targeted to ER+ cells, which could generally represent endocrine therapy for breast cancer.) Cell populations were characterized by mutation profiles, ER status, and response to estrogen suppression. Simulations were continued until development of DEA resistance, identified by reversal of growth suppression, and the mutations present at that point were analyzed for change.

Results: 3500 DEABM simulations over 40 years generated 69 wild-type ER+ tumors and 119 BRCA ER+ tumors. Of these 25% of wild-type ER+ tumors were sensitive to DEA vs. 35% of BRCA1 tumors, consistent with previously reported response rates. The percentage of ER+ cells was higher in initially sensitive tumors than in initially resistant tumors (84% vs. 66%, p = .001). Tumors initially resistant to DEA were more likely to carry mutations in the genes p53, E-cadherin and Myc (p = .001). Sensitive tumors acquired a significant increase in mutations during the interval between responsiveness to DEA and development of resistance (p = .001). Lastly, sensitive BRCA1 carriers were more likely to convert from ER+ to ER- status (p = .001).

Discussion: The DEABM generated simulated breast tumors with intra-tumoral heterogeneity that demonstrate varied responsiveness to DEA, similar to what is observed clinically. These results suggest there may be definable patterns of tumor evolution in response to DEA that could potentially guide the development or sequencing of therapeutic regimens. Computational models such as the DEABM can aid in visualizing molecular data in a dynamic form and allow researchers to carry out “thought experiments” concerning tumor behavior and intervention effect.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-10-02.