Proteomic analysis of human bone marrow mesenchymal stem cells transduced with human telomerase reverse transcriptase gene during proliferation

OBJECTIVES

Previous studies have reported immortalization and tumorigenicity of human mesenchymal stem cells (hMSCs) transduced with exogenous human telomerase reverse transcriptase (hTERT). We also have established a line of hMSCs transduced with hTERT (hTERT-hMSCs) and we have cultured these cells for 290 population doublings (PDs) during which they demonstrated a large proliferation potential but with no tumorigenicity. The aim of this study was to investigate the protein expression profile of hTERT-hMSCs with two-dimensional gel electrophoresis and peptide mass fingerprinting by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, to be able to analyse the effects of exogenous hTERT on protein expression in hMSCs.

MATERIALS AND METHODS

We generated proteome maps of primary hMSCs and hTERT-hMSCs at PD 95 and PD 275.

RESULTS

A total of 1543 +/- 145 protein spots in gels of primary MSCs at PD 12, 1611 +/- 186 protein spots in gels of hTERT-hMSCs at PD 95 and 1451 +/- 126 protein spots in gels of hTERT-hMSCs at 275 PD were detected. One hundred of these were successfully identified, including 20 which were differentially expressed.

CONCLUSIONS

The results suggest that sustaining levels of prohibitin and p53 expression along with differential expression of proteins in hTERT-hMSCs provide an insight into lack of transforming activity of hTERT-hMSCs during cell proliferation.

A Novel Adipocytokine, Visceral Adipose Tissue-derived Serine Protease Inhibitor (Vaspin), and Obesity

Visceral adipose tissue-derived serine protease inhibitor (vaspin) is an interesting novel adipocytokine with insulin-sensitizing effects. Some studies have suggested that vaspin could play an important role in the development of obesity and metabolic disorders. The induction of vaspin mRNA expression could represent a compensatory mechanism associated with obesity, severe insulin resistance and type 2 diabetes mellitus, however it is unclear whether a correlation exists between human vaspin serum levels and markers of insulin sensitivity and glucose or lipid metabolism. Vaspin serum concentrations have been shown to be lower in lean subjects and competitive sportsmen with long-term physical training, but they are increased with weight loss associated with a physical training programme. In conclusion, there is at present no clear proof of a causal link between vaspin and visceral fat accumulation, or insulin resistance. This article reviews the role of vaspin in obesity-associated diseases and its potential as a new biomarker for obesity and impaired insulin sensitivity.

Controlled multipulse loading with a stuffed striker in classical split Hopkinson pressure bar testing

Controlled multipulse loading in classical split Hopkinson pressure bar (SHPB) testing is highly desirable for investigating loading history dependent phenomena but rarely explored. Here, we present a novel technique to achieve controlled multipulse loading in SHPB testing with a stuffed striker. This stuffed striker consists of a striker tube, and a striker bar and a gap enclosed inside the tube; upon impact on the input bar, it can produce two separated loading pulses. The gap controls the delay of the second pulse with respect to the first pulse, and the pulse separation (dwell time) can be continuously tuned from zero to hundreds of microseconds. The combination of the stuffed striker and the Lindholm technique [J. Mech. Phys. Solids 12, 317 (1964)] allows for controlled multipulse loading with triple or more pulses. We have validated the working principle of this technique with experiments, and demonstrated its feasibility and flexibility for acquiring relevant dynamic data with double- and triple-pulse loading on polycrystalline Cu. This precisely controlled multipulse loading technique is readily implementable and can be applied to investigating the dynamic response of a wide range of materials.

Regulation of IKKbeta by miR-199a affects NF-kappaB activity in ovarian cancer cells

Cancer progression is an abnormal form of tissue repair characterized by chronic inflammation. IkappaB kinase-beta (IKKbeta) required for nuclear factor-kappaB (NF-kappaB) activation plays a critical role in this process. Using EOC cells isolated from malignant ovarian cancer ascites and solid tumors, we identified IKKbeta as a major factor promoting a functional TLR-MyD88-NF-kappaB pathway that confers to EOC cell the capacity to constitutively secrete proinflammatory/protumor cytokines and therefore promoting tumor progression and chemoresistance. Furthermore, we describe for the first time the identification of the microRNA hsa-miR-199a as a regulator of IKKbeta expression. Our study describes the property of ovarian cancer cells to enhance the inflammatory microenvironment as a result of the expression of an active IKKbeta pathway. Identification of these markers in patients' tumor samples may facilitate the adequate selection of treatment and open new venues for the development of effective therapy for chemoresistant ovarian cancers.

Cancers take their Toll--the function and regulation of Toll-like receptors in cancer cells

Cancer could be deemed as an abnormal and uncontrolled tissue repair process. Therefore, it would not be surprising that factors that function in the tissue repair process, such as cytokines, chemokines, growth factors and Toll-like receptor (TLR) ligands, as well as growth signals for compensatory proliferation, would also be key factors in regulating and enhancing cancer progression. The TLR pathways, which play a critical role in tissue repair, are also key regulators in cancer progression as well as chemoresistance. TLRs serve as cell surface sensors that can initiate pathways leading to proliferation and chemoresistance; as well as mediators that are able to regulate the infiltrating immune cells to provide further support for cancer progression.

Optimized plan of centralized and decentralized wastewater reuse systems for housing development in the urban area of Xi'an, China

In an arid and water deficient urban area, such as Xi'an in the northwest region of China, gardening and forestation often use large amounts of tap water. Therefore, there is a need for treated wastewater reuse for such purpose to mitigate urban water shortage, especially in the newly developed housing area, where a high green coverage is often required for both commercial value and living condition improvement. Supply of the treated wastewater through a centralized system which has been planned and partially constructed is one measure to meet such need, but it may require an extension of the distribution system for a full coverage of the whole city area. A supplementary measure is to construct decentralized wastewater treatment and reuse (DESAR) systems in areas that are distant from the planned centralized system. In order to optimize the plan of wastewater reuse for housing development in the urban area, the authors analyzed the existing plan of centralized wastewater reuse and the envisaged plan of housing development in Xi'an urban area. A method was proposed for selection of a feasible way of reclaimed water reuse from two options, namely centralized and decentralized ones, by introducing a critical distance L0 which depends on the relationship between the cost for DESAR system installation and that for water delivery pipeline construction. If the distance from the project site to the nearest access point of the centralized system L is shorter than L0 then using reclaim water from the centralized system becomes more feasible, and otherwise DESAR system installation becomes more feasible. A distribution map was thus obtained to show an optimized plan of centralized and decentralized wastewater reuse systems for housing development in Xi'an city. An example was also given to show the advantage of a DESAR system installed.

The angiogenic potential of three-dimensional open porous synthetic matrix materials

Angiogenesis is a complex multistage process involving multiple factors and numerous cells. The use of the Chorioallantoic Membrane (CAM) assay is well documented as a method to investigate angiogenesis. This technique is ideal for screening samples, but requires an objective analysis technique. The angiogenic response of vascular endothelial growth factor (VEGF) was used to confirm that computer-based image analysis was able to quantify angiogenesis. Image analysis was used on samples of increasing porosity of PLLA to determine the effect of pore size on angiogenesis. Another effect also noted was that of an inflammatory response co-incident with angiogenesis. The difference in pore size made a difference to both angiogenesis and inflammation. Real-time polymerase chain reaction (PCR) was used with primers for TNF-alpha to demonstrate and measure the presence of an inflammatory response.

Isolated diaphragmatic tremor: Is there a spectrum in "respiratory myoclonus"?

BACKGROUND

Respiratory myoclonus or diaphragmatic flutter is an unusual movement disorder with abnormal diaphragmatic activity, which may be associated with respiratory symptoms. The effects of distracting maneuvers on diaphragmatic activity have not been investigated.

METHODS

Two patients with nondisabling abdominal movements of suspected diaphragmatic origin were studied with surface and needle electromyography (EMG).

RESULTS

The abdominal movements resulted from isolated, rhythmic diaphragmatic contractions with variable EMG burst duration, suppressibility with breath-holding and distracting maneuvers, and other attributes of volitional control.

CONCLUSION

"Respiratory myoclonus" may be a heterogeneous disorder ranging from synchronous movements of the diaphragm and other respiratory muscles associated with respiratory compromise, to diaphragmatic movements under at least some volitional control with no respiratory or functional disability. The latter group could be designated phenomenologically as "isolated diaphragmatic tremor."

Association of HLA genes with ankylosing spondylitis in Han population of eastern China

Ankylosing spondylitis (AS) is a chronic inflammatory disorder with a multifactorial genetic basis. HLA-B27 was reported with the greatest susceptibility to AS but did not act alone. The aim of this study was to search for other gene(s) associated with AS independently of HLA-B27 using 13 microsatellite markers spanning 1.5 Mb from locus TAP1 to HLA-Cw and a single-nucleotide polymorphism marker within NFkappaBIL1 gene promoter. Genotyping for microsatellites was performed in 175 AS patients of eastern Chinese and 219 ethnically matched healthy controls using polymerase chain reaction with fluorescence-labelled primers, whereas the SNP marker was genotyped by direct DNA sequencing. Allele as well as haplotype frequencies were compared between cases and controls, and a linkage disequilibrium analysis was performed to estimate the LD relationship between the candidate regions. The frequencies of alleles D6S2811*128, STR_MICA*A5.1 and D6S2672*109, as well as haplotypes D6S2811*128-D6S2927*213-D6S2810*340, D6S2927* 221-D6S2810*350-MICA*A5.1, and D6S2810*350-MICA*A5.1-D6S2800* 136 were significantly increased in B27-positive AS patients when compared with B27-positive controls. The results indicated that there may be other gene(s) within the HLA region, especially around locus HLA-B or HLA-Cw, with susceptibility to AS independently of HLA-B27.

Regulation of two key nuclear enzymatic activities by the 7SK small nuclear RNA

7SK is a highly conserved small nuclear RNA (snRNA) in vertebrates. Since its discovery in 1968, little had been known about its function until recently, when 7SK was found to associate with the general transcription elongation factor P-TEFb. Together with the HEXIM1 protein, 7SK sequesters P-TEFb into a kinase-inactive complex, where it mediates HEXIM1's inhibition of P-TEFb. This helps maintain P-TEFb in a functional equilibrium to control transcription, cell growth, and differentiation. Although highly abundant, only a small fraction of 7SK is P-TEFb-bound. Using affinity purification, we have identified APOBEC3C as another 7SK-associated protein. As a member of the APOBEC family that functions in diverse processes through deaminating cytosine in DNA, it is unclear how APOBEC3C's activity is controlled to prevent its mutations of genomic DNA. We show that most of APOBEC3C interact with about half of nuclear 7SK, which suppresses APOBEC3C's deaminase activity and sequesters APOBEC3C in the nucleolus where it could be at a safe distance from most genomic sequences. Because the DNA substrate-binding site in APOBEC3C differs from the region for 7SK binding, 7SK does not act as a substrate competitor in inhibiting APOBEC3C. The demonstration of 7SK's suppression of yet another enzyme besides P-TEFb suggests a general role for this RNA in regulating key nuclear functions.

Pemetrexed (P) in relapsed small cell lung cancer (SCLC): Preliminary results of a phase II trial

7716

Background: Pts with relapsed SCLC have a poor prognosis and few effective treatment options. P is a novel multitargeted antifolate that is active and well-tolerated as a single agent in lung cancer. We undertook a trial to assess the efficacy and safety of single- agent P in both chemosensitive (S) and chemorefractory (R) relapsed SCLC pts. Methods: Eligible pts had limited or extensive- stage SCLC, PS 0 to 2, and only 1 prior chemo regimen. S pts were defined as having had a prior response with disease progression >2 mos from end of 1st-line chemo. R pts were those who progressed while on 1st-line therapy, or had any response but progression <2 mos from end of 1st-line chemo. The initial P dose tested was 500 mg/m2 q 21 d. Planned sample sizes were 36 S pts in a 2-stage sequential fashion with potential early stopping for lack of efficacy or unacceptable toxicity, and 25 R pts in a single-stage design with no stopping rule. The stopping rule was invoked when <3 of 14 qualified S pts responded. The protocol was then amended to evaluate P at 900 mg/m2 in additional cohorts of 40 S and 40 R pts. Pts were to receive folic acid and Vitamin B12 prior to treatment with P. The primary outcome measure was response rate. Results: From 7/04 to 3/06, 121 pts were enrolled, with 116 pts treated. S and R pts were analyzed separately at both dose levels. S pts (n=56): M/F, 29/27; median age 65 (range 43–82); PS 0/1/2, 25/23/8. R pts (n=65): M/F, 31/34; median age 64 (range, 35–85); PS 0/1/2, 16/37/12. *3 S pts treated with P 900 mg/m2 remain with disease control after a minimum of 11 mos of follow-up. Conclusions: Preliminary clinical benefit rates (CR+PR+SD) of 20% and 17.4% achieved respectively in S and R pts treated with P 500 mg/m2 suggest modest activity of single-agent P in relapsed SCLC. P can be given at a dose of 900 mg/m2 without a significant increase in Grades 3–4 toxicities, although this does not appear to increase efficacy.

[Table: see text] [Table: see text]