Recombinant human endostatin, Endostar, enhances the effects of chemo-radiotherapy in a mouse cervical cancer xenograft model

BACKGROUND

The effects of recombinant human endostatin, Endostar, combined with concurrent chemo-radiotherapy (CCRT) on tumor growth, angiogenesis and lymphangiogenesis in a mouse xenograft model of cervical cancer was investigated.

METHODS

HeLa cells were injected subcutaneously to establish mouse xenograft models and mice were treated with normal saline (control), CCRT with cisplatin (CDDP), Endostar, or a combination of Endostar and CCRT. Growth, metastasis, and angiogenesis of tumors was monitored.

RESULTS

Tumorogenic activity of tumor cells in the CCRT, Endostar and combination Endostar-CCRT treatment groups was markedly decreased compared with the activity in the NS group (p < 0.05). The most significant inhibition of tumor growth was observed in the Endostar with CCRT group. Lymph node metastases in the Endostar with CCRT group (12.5%) and Endostar alone group (25%) were lower compared to the CCRT group (42.8%) and NS group (66.7%; p < 0.05). Endostar was also found to inhibit tumor angiogenesis. Endostar induced apoptosis of HeLa cells in vivo, and inhibited expression of VEGF and HIF-1alpha in vivo and in vitro.

CONCLUSION

Endostar enhanced the anti-cancer effect of CCRT in a mouse xenograft model of cervical cancer. These findings thus provide a new strategy to treat cervical cancer.

The efficacy of chemotherapy in the advanced NSCLC patients who failed with the treatment of EGFR-TKI

e19078

Background: EGFR-TKI such as gefitinib and erlotinib were used as standard 2nd/3rd line therapy in previously treated NSCLC. However, those who benefit from EGFR-TKI will inevitably progress from the disease. We reported the efficacy of chemotherapy(CT) in the advanced NSCLC pts failed with the previously 2nd/3rd line treatment of EGFR-TKIs. Methods: Eligibility criteria included advanced NSCLC pts who got disease control(included CR, PR or SD) initially from TKI therapy and then progressed, PS = 0–2, and normal fatal organ function. Pts received systemic CT (docetaxal, pemetrexed, gemicitabine, novelbine or combined with platinum agent) until disease progression or unacceptable toxicity. Results: 32 pts were enrolled from Oct 15 2007 to Nov 30 2008. Demographics: M 56.3%/F 43.7%; median age 56 y [range 34–72]; stage IV 100%; PS 0/1/2: 3 (9.4%)/22(68.8%)/7(21.8%); adenocarcinoma/non-adenocarcinoma 29(90.6%)/3(9.4%); EGFR-TKI treatment duration >6 m 20(62.5%) /< 6 m 12(37.5%); monotherapy 16 (50%)/ doublets 16 (50%). All pts were evaluable for efficacy; partial response in 5 cases (15.6%), stable disease in 21 cases(37.5%), progressive disease in 15 (46.9%) ( Table ). The response of CT was not related with gender, age, regimens, but these with TKI treatment > 6 m achieved a significantly better response than those < 6 m(p=0.01) and these with PS 0–1 got a marginally significantly better response than PS 2(p=0.095). The toxicity was acceptable. Median progression free survival was 3.4 months and it was not correlated with the gender, age and regimens, but PFS were significant longer in the pts received > 6 m of TKI (median 4.8 vs 1.9, p=0.009) and with PS 0–1 (median 4.7 vs 1.9, p=0.002). Conclusions: Pts benefited from TKI therapy and developed progressive disease could also benefit from CT. The response duration of EGFR-TKI and performance status could be predictive for the better efficacy of CT.

[Table: see text]

No significant financial relationships to disclose.

A tiered approach for aquatic risk assessment of alcohol ethoxylates

An environmental risk assessment approach for alcohol ethoxylate (AE) mixtures was recently published which required the concentrations of the AE homologues in a mixture. The application of this approach can be limited in certain circumstances because AE homologue concentrations would generally not be available without environmental monitoring and would be difficult to estimate by exposure modeling. A tiered assessment approach was proposed in this study which required AE homologue concentrations only in the last tier. A key parameter in the tiered approach was based on Monte Carlo simulation in which simulated AE mixtures were decomposed into plausible combinations of homologues. The value of this parameter was determined so that the probability of false-negative conclusions in the tiered risk assessment approach was minimized. The use of the tiered approach was demonstrated.

Probabilistic risk assessment for zinc in some commercial dishwashing detergents: the anaerobic digestion processes in US POTWs

A US patent was issued to a commercial dishwashing detergent composition in which soluble zinc serves as an anti-corrosion agent. Since the detergents are used in a down-the-drain fashion, some of the detergents are discharged as wastewater and treated in publicly owned treatment works (POTWs). A risk assessment was previously conducted which focused on the nitrification processes in US POTWs. As a conservative pollutant, zinc removed from wastewater during treatment is transferred to sludges and at sufficiently high concentrations may inhibit the sludge treatment processes. In the present assessment, a probabilistic risk assessment was conducted to quantitatively determine the risk of zinc in the detergents to the anaerobic digestion processes in US POTWs. The procedure for POTW local limit development designed by the US Environmental Protection Agency (EPA) was used as a reference when conducting the risk assessment. The assessment took into account the background zinc concentrations in POTW influents and was conducted at different market penetration rates (MPRs) for the US market of detergents based on the patented formula. Several factors were present that contributed to the conservativeness of the assessment. Results indicate that zinc in detergents does not present a significant risk to the anaerobic digestion processes in POTWs at a MPR up to 10%, with a probability of anaerobic digestion inhibition of below 1%.

Cerebral White Matter Lesions and Cognitive Function in a Non-demented Chinese Veteran Cohort

This study examined the association between cerebral white matter lesions (WMLs) and cognitive function in a male, non-demented Chinese veteran cohort. A total of 662 participants underwent CT scan and cognitive function assessments; 51 were excluded from the analysis because they exhibited non-lacunar infarcts or suspected dementia. Subjects were allocated to one of four groups according to WML status and between-group comparisons were made for seven cognitive function tests. Logistic regression was used to assess odds ratios for impaired performance associated with WML status. In all cognitive tests, subjects with severe WMLs differed significantly from those without WMLs or with mild WMLs, and in three tests subjects with severe WMLs differed significantly from those with moderate WMLs. For each cognitive test severe WMLs were strongly associated with increased risk of impaired performance. Severe WMLs were associated with greater diminished cognitive function and there may be a WML threshold after which, in elderly Chinese subjects, an impact on cognitive function occurs.

Severe acute graft-vs-host disease in a patient with acute monocytic leukemia having a recombination event between HLA-A/B loci from a multiple recombinant family

Human leukocyte antigen (HLA) recombination, particularly multiple recombinations can produce novel haplotypes, thereby complicating donor-recipient selection and possibly inducing severe graft-vs-host disease (GVHD) after nonfully matched allogeneic hematopoietic stem cell transplantation. Here, we report for the first time that a 30-year-old female acute monocytic leukemia patient with an HLA-A/B recombinant haplotype, who has three unmatched and one HLA-B/DRB1 recombinant haplotype siblings, presented grade IV acute GVHD (aGVHD) after transplantation from a sibling with a single allele only mismatch at the classical HLA-A locus. Furthermore, using a new three-dimensional structure modeling application, we inferred that the structural differences in peptide-binding and T-cell receptor interaction sites can significantly change the immunogenicity of mismatched HLA molecules, potentially one of the main causes of aGVHD.

Splice variants of the CYP27b1 gene and the regulation of 1,25-dihydroxyvitamin D3 production

The cytochrome P450 25-hydroxyvitamin D3-1alpha-hydroxylase (CYP27b1) plays a pivotal role in vitamin D physiology by catalyzing synthesis of active 1,25-dihydroxyvitamin D3 [1,25(OH)2D3]. In common with other P450s, CYP27b1 is known to exhibit alternative splicing. Here we have cloned and sequenced several novel intron 2-containing, noncoding splice variant mRNAs for CYP27b1 in 1,25(OH)2D3-producing HKC-8 human proximal tubule and THP-1 monocytic cells. Regulation of 1,25(OH)2D3 synthesis in these cell lines by calciotropic and noncalciotropic factors was associated with altered expression of the CYP27b1 splice variants. To assess the functional significance of this, HKC-8 cells were transfected with short hairpin RNA (shRNA) to inhibit mRNAs containing sequences from intron 2. This resulted in a significant increase in the expression of CYP27b1 protein and synthesis of 1,25(OH)2D3 by HKC-8 cells compared with control cells for two different intron 2-containing shRNAs (both P<0.001). shRNA to intron 2 had no significant effect on the levels of wild-type CYP27b1 mRNA, suggesting a posttranscriptional mechanism of action. By contrast, shRNA to wild-type CYP27b1 suppressed transcription and activity of the enzyme by 70 and 31%, respectively (both P<0.01). These data indicate that noncoding splice variants of CYP27b1 are functionally active and may play a significant role in the regulation of 1,25(OH)2D3 synthesis during normal physiology.

Probabilistic risk assessment for zinc in some commercial dishwashing detergents: the nitrification processes in US POTWs

A US patent was issued to a commercial dishwashing detergent composition in which soluble zinc is used to protect glassware from corrosion. Some of the consumed detergents are discharged as wastewater and treated in publicly owned treatment works (POTWs). A probabilistic risk assessment was conducted to quantitatively determine the risk of zinc in the detergents to the nitrification processes in US POTWs. The procedure for POTW local limit development designed by the US Environmental Protection Agency (EPA) was used as a reference when conducting the risk assessment. The assessment took into account the background zinc concentrations in POTW influents and potential shock loading patterns, and was conducted at different market penetration rates (MPRs) for the US market of detergents based on the patented formula. The assessment involved several conservative factors including conservative determination of primary treatment efficiency, bioavailability, inhibition concentration, configuration of the nitrification process, as well as background zinc concentration in wastewater. With the conservative factors in the assessment, it was found that zinc in detergents does not present a significant risk to the nitrification processes in POTWs at a MPR up to 10%. It was noted that additional analyses would be required when the MPR is higher than 10% to adequately account for the effects of the conservative factors on the result of the assessment.

FTY720 suppresses interleukin-1beta-induced secretory phospholipase A2 expression in renal mesangial cells by a transcriptional mechanism

BACKGROUND AND PURPOSE

FTY720 is a potent immunomodulatory prodrug that is converted to its active phosphorylated form by a sphingosine kinase. Here we have studied whether FTY720 mimicked the action of sphingosine-1-phosphate (S1P) and exerted an anti-inflammatory potential in renal mesangial cells.

EXPERIMENTAL APPROACH

Prostaglandin E(2) (PGE(2)) was quantified by an enzyme-linked immunosorbent-assay. Secretory phospholipase A(2) (sPLA(2)) protein was detected by Western blot analyses. mRNA expression was determined by Northern blot analysis and sPLA(2)-promoter activity was measured by a luciferase-reporter-gene assay.

KEY RESULTS

Stimulation of cells for 24 h with interleukin-1beta (IL-1beta) is known to trigger increased PGE(2) formation which coincides with an induction of the mRNA for group-IIA-sPLA(2) and protein expression. FTY720 dose-dependently suppressed IL-1beta-induced IIA-sPLA(2) protein secretion and activity in the supernatant. This effect is due to a suppression of cytokine-induced sPLA(2) mRNA expression which results from a reduced promoter activity. As a consequence of suppressed sPLA(2) activity, PGE(2) formation is also reduced by FTY720. Mechanistically, the FTY720-suppressed sPLA(2) expression results from an activation of the TGFbeta/Smad signalling cascade since inhibition of the TGFbeta receptor type I by a specific kinase inhibitor reverses the FTY720-mediated decrease of sPLA(2) protein expression and sPLA(2) promoter activity.

CONCLUSIONS AND IMPLICATIONS

In summary, our data show that FTY720 was able to mimic the anti-inflammatory activity of TGFbeta and blocked cytokine-triggered sPLA(2) expression and subsequent PGE(2) formation. Thus, FTY720 may exert additional in vivo effects besides the well reported immunomodulation and its anti-inflammatory potential should be considered.

Mitochondrial cholesterol transport: A possible target in the management of hyperlipidemia

Sterol 27-hydroxylase (CYP27A1) may defend cells against accumulation of excess cholesterol, making this enzyme a possible target in the management of hyperlipidemia. The study objective was to analyze cholesterol homeostatic responses to increases in CYP27A1 activity in HepG2 cells and primary human hepatocytes. Increasing CYP27A1 activity by increasing enzyme expression led to significant increases in bile acid synthesis with compensatory increases in HMG-CoA reductase (HMGR) activity/protein, LDL receptor (LDLR) mRNA, and LDLR-mediated cholesterol uptake. Under these conditions, only a small increase in cellular 27-hydroxycholesterol (27OH-Chol) concentration was observed. No changes were detected in mature sterol regulatory element-binding proteins (SREBP) 1 or 2. Increasing CYP27A1 activity by increasing mitochondrial cholesterol transport (i.e., substrate availability) led to greater increases in bile acid synthesis with significant increases in cellular 27OH-Chol concentration. Mature SREBP 2 protein decreased significantly with compensatory decreases in HMGR protein. No change was detected in mature SREBP 1 protein. Despite increasing 27OH-Chol and lowering SREBP 2 protein concentrations, LDLR mRNA increased significantly, suggesting alternative mechanisms of LDLR transcriptional regulation. These findings suggest that regulation of liver mitochondrial cholesterol transport represents a potential therapeutic strategy in the treatment of hyperlipidemia and atherosclerosis.