Carbon monoxide releasing molecule-3 inhibits concurrent tumor necrosis factor-α- and interleukin-1β-induced expression of adhesion molecules on human gingival fibroblasts

BACKGROUND AND OBJECTIVE

Carbon monoxide releasing molecule-3 (CORM-3) is a newly reported compound that has shown anti-inflammatory effects in a number of cells. In this study, we aimed to investigate the influence of CORM-3 on concurrent tumor necrosis factor-α (TNF-α)- and interleukin (IL)-1β-induced expression of adhesion molecules on human gingival fibroblasts (HGF).

MATERIAL AND METHODS

HGF were cultured from the explants of normal gingival tissues. Cells were costimulated with TNF-α and IL-1β in the presence or absence of CORM-3 for different periods of time. The expression of adhesion molecules, nuclear factor-kappaB (NF-κB) and phosphorylated p38 was studied using western blotting. RT-PCR was applied to check the expression of the adhesion molecules at the mRNA level. The activity of NF-κB was analysed using a reporter gene assay.

RESULTS

CORM-3 inhibited the up-regulation of intercellular adhesion molecule 1, vascular cell adhesion molecule 1 and endothelial leukocyte adhesion molecule in HGF after costimulation with TNF-α and IL-1β, which resulted in the decreased adhesion of peripheral blood mononuclear cells to these cells. Sustained activation of the NF-κB pathway by costimulation with TNF-α and IL-1β was suppressed by CORM-3, which was reflected by a reduced NF-κB response element-dependent luciferase activity and decreased nuclear NF-κB-p65 expression. CORM-3 inhibited MAPK p38 phosphorylation in response to stimulation with proinflammatory cytokines.

CONCLUSION

The results of this study bode well for the application of CORM-3 as an anti-inflammatory agent to inhibit NF-κB activity and to suppress the expression of adhesion molecules on HGF, which suggests a promising potential for CORM-3 in the treatment of inflammatory periodontal disease.

Epidermal growth factor receptor regulates MET levels and invasiveness through hypoxia-inducible factor-1alpha in non-small cell lung cancer cells

Recent studies have established that amplification of the MET proto-oncogene can cause resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) in non-small cell lung cancer (NSCLC) cell lines with EGFR-activating mutations. The role of non-amplified MET in EGFR-dependent signaling before TKI resistance, however, is not well understood. Using NSCLC cell lines and transgenic models, we demonstrate here that EGFR activation by either mutation or ligand binding increases MET gene expression and protein levels. Our analysis of 202 NSCLC patient specimens was consistent with these observations: levels of MET were significantly higher in NSCLC with EGFR mutations than in NSCLC with wild-type EGFR. EGFR regulation of MET levels in cell lines occurred through the hypoxia-inducible factor (HIF)-1alpha pathway in a hypoxia-independent manner. This regulation was lost, however, after MET gene amplification or overexpression of a constitutively active form of HIF-1alpha. EGFR- and hypoxia-induced invasiveness of NSCLC cells, but not cell survival, were found to be MET dependent. These findings establish that, absent MET amplification, EGFR signaling can regulate MET levels through HIF-1alpha and that MET is a key downstream mediator of EGFR-induced invasiveness in EGFR-dependent NSCLC cells.

NF-kappaB activation mediates resistance to IFN beta in MLL-rearranged acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL) harboring the t(4;11) translocation is associated with a very poor prognosis; innovative treatment strategies are required to improve the current 5-year survival rate of 30-40%. Interferon beta (IFN beta) has shown promise in the treatment of both solid and hematologic malignancies, although the short half-life and toxicity associated with high doses have limited its clinical utility. To overcome these limitations, we investigated the effect of continuous, gene transfer-mediated delivery of IFN beta using adeno-associated virus (AAV)-mediated expression, on ALL cells with the t(4;11) translocation. We found that this method of IFN beta delivery resulted in complete remission of leukemia in a murine model. However, leukemic cells eventually became resistant to IFN beta and relapse was observed. Activation of NF-kappaB was identified as a mechanism for IFN beta resistance, and inhibition of NF-kappaB activity in resistant cells sensitized cells to IFN beta. IFN beta combined with agents that inhibit NF-kappaB could have therapeutic potential in the treatment of children with mixed lineage leukemia subtype ALL.

The Cell of Breast Cancer Origin Affects Tumor Estrogen Receptor Status

It has been known for some time that breast cancer phenotype is dependent upon the initiating oncogene. However, it has only recently been demonstrated that breast cancer phenotype, including tumor histopathology, gene expression profile, and metastatic potential, may also depend upon the cellular subtype from which a tumor arises. Breast tumor estrogen receptor (ER) status is a common prognostic factor, and approximately 70% of all breast tumors are ER+; that is, they expresse ER in ≥5% of tumor cells. However, it remains unknown which factors determine breast cancer ER status. It is possible that the cell of tumor origin plays a role in determining the ER status of the resulting tumor. Our lab has developed a method to somatically introduce oncogenes into a developmentally normal mouse mammary gland with temporal control using the modified avian retrovirus RCAS. We have generated transgenic mice that express the RCAS receptor TVA under mammary cell selective markers and demonstrated our ability to infect individual cells and induce mammary tumors. In this study we used an RCAS vector encoding polyoma virus middle T antigen (PyMT) to infect transgenic adult MMTV-tva or WAP-tva mice. The MMTV LTR is though to be active in several different mammary cell types including luminal epithelial, progenitor, and stem cells. WAP is primarily active in more highly differentiated mammary epithelial cells. Tumors induced by RCAS-PyMT differ in histopathology between the two lines. Those arising in MMTV-tva mice have a predominately solid morphology, while those arising in WAP-tva mice display a predominately papillary morphology. Interestingly, we found that the majority of tumors arising in MMTV-tva mice are ER+ (61%), while tumors arising in WAP-tva mice are predominately ER- (95%). Our data suggest that tumors induced by the same oncogene from distinct cellular subtypes in the mouse mammary epithelium can significantly vary in histopathology, and that tumor ER status can be dependent upon the cell of tumor origin.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 2163.

Reduced apoptosis of mouse macrophages induced by yscW mutant of Yersinia pestis results from the reduced secretion of YopJ and relates to caspase-3 signal pathway

The virulence of the pathogenic Yersinia species depends on a plasmid-encoded type III secretion system (T3SS) that injects six Yersinia outer protein (Yop) effector proteins into the cytosol of macrophages, leading to disruption of host defence mechanisms. Here, we report that a T3SS structural protein YscW of Yersinia pestis contributed to the induction of apoptosis of murine macrophages. The apoptotic percentage of macrophages, from both mouse peritoneal cavity and spleen, and of RAW264.7 cell line, caused by the yscW mutant strain was significantly lower than that by wild type (WT) Y. pestis and yscW complemented strain. Meanwhile, detection of caspase-3 activity in macrophages, a key apoptosis-inducing protein, showed coincident results with the changes of macrophage apoptosis induced by WT, yscW mutant and complemented strains, indicating that macrophage apoptosis was related to caspase-3 signal pathways. However, ectopic expression of YscW in RAW264.7 cells cannot increase the macrophage apoptosis and death, suggesting that YscW itself could not induce macrophage apoptosis directly. To get insight into the mechanism of this phenomenon, we investigated the secretion of YopJ, which has been thought to be the only Yop effector related to apoptosis, in WT, mutant and complemented strains, respectively. Results showed that in yscW mutant strain, secretion of YopJ was decreased significantly in the supernatant than that in WT or complemented strain. This means although YscW does not induce apoptosis directly, it can indirectly affect apoptosis through reducing the secretion of YopJ.

Ecology-based screen identifies new metabolites from a Cordyceps-colonizing fungus as cancer cell proliferation inhibitors and apoptosis inducers

OBJECTIVES

This study aims to identify new anti-cancer agents from Cordyceps-colonizing fungi, using an ecology-based approach. It also aims to explore their anti-cell proliferative mechanisms, and to evaluate their anti-tumour effects in vivo.

MATERIALS AND METHODS

Extracts from Cordyceps-colonizing fungi were tested on HeLa cells, and active extracts were separated to obtain anti-tumour metabolites; their structures were elucidated by mass and nuclear magnetic resonance spectroscopy. Cell cycle analysis was evaluated using flow cytometry. Tumour formation assays were performed using C57BL/6J mice.

RESULTS

Based on ecological considerations, the selected extracts were subjected to initial anti-tumour screening. Bioassay-guided fractionation of the active extract afforded two new epipolythiodioxopiperazines, named gliocladicillins A (1) and B (2). (A) 1 and B (2) inhibited growth of HeLa, HepG2 and MCF-7 tumour cells. Further study demonstrated that both preparations arrested the cell cycle at G(2)/M phase in a dose-dependent manner, and induced apoptosis through up-regulation of expression of p53, p21, and cyclin B, and activation of caspases-8, -9 and -3. These data imply that gliocladicillins A (1) and B (2) induce tumour cell apoptosis through both extrinsic and intrinsic pathways. In addition, in vivo studies showed that they displayed significant inhibitory effects on cell population growth of melanoma B16 cells implanted into immunodeficient mice.

CONCLUSIONS

Gliocladicillins A (1) and B (2) are effective anti-tumour agents in vitro and in vivo and should be further evaluated for their potential in clinical use.

Curing of four different plasmids in Yersinia pestis using plasmid incompatibility

AIMS

Plasmids are critical for the pathogenicity of Yersinia pestis. In order to carry out a systematic investigation of their role in pathogenesis, we cured plasmids from Y. pestis.

METHODS AND RESULTS

Each plasmid's replicon of Y. pestis was cloned into plasmid pEX18Gm containing a counter-selectable sacB gene, and was then introduced into Y. pestis strain 201 by electroporation. Strains containing recombinant plasmids were cultivated under antibiotic selection. The resultant plasmid-curing colonies, identified by specific polymerase chain reactions, were then cured off pEX18Gm under sucrose pressure. This method was used to successfully cure all four plasmids of Y. pestis, singly or in different combinations.

CONCLUSIONS

Naturally evolving plasmids in Y. pestis are difficult to remove by conventional curing methods. We employed a method based on plasmid incompatibility to cure the plasmids from Y. pestis, which confirmed the efficacy of this method for curing plasmids with different types of replicons from one bacterium.

SIGNIFICANCE AND IMPACT OF THE STUDY

There have been no reports on the curing of multiple plasmids by using replication mechanisms from one bacterium with this technique. In the present study, we were able to successfully apply this methodology to cure four plasmids from Y. pestis, confirming its feasibility.

Randomized, double-blinded trial evaluation of valsartan/hydrochlorothiazide combination therapy in mild to moderate essential hypertension in north-east China

In this randomized, double-blind study, 126 mild to moderate essential hypertensive patients from northern China were studied to determine the efficacy and safety of a combination therapy of valsartan and hydrochlorothiazide. Patients were randomized to the V80/H12.5 (80 mg valsartan/12.5 mg hydrochlorothiazide) group or the V80 (80 mg valsartan) group. Six weeks after treatment, the mean decrease from baseline in mean sitting systolic blood pressure (MSSBP) was significantly higher in the V80/H12.5 group than the V80 group, but there was no difference in the change of mean sitting diastolic blood pressure (MSDBP) in the two groups. Overall, 80.33% and 70.97% had a controlled response (normalized MSDBP), and 85.25% and 77.42% had a diastolic response (normalized MSDBP or > 10 mmHg reduction in MSDBP) in the V80/H12.5 and V80 groups, respectively (not significantly different). The incidence of adverse events was also similar between the two groups. The combination of 80 mg valsartan/12.5 mg hydrochlorothiazide was efficacious and well tolerated in mild and moderate essential hypertensive patients.

Combination of KIR and HLA gene variants augments the risk of developing birdshot chorioretinopathy in HLA-A*29-positive individuals

Birdshot chorioretinopathy (BCR), a chronic ocular inflammatory disease with characteristic choroidal lymphocytic infiltrates, has been strongly associated with human leukocyte antigen (HLA)-A29. Although HLA-A29 occurs frequently in all populations, BCR affects only a small percentage of HLA-A29-positive Caucasians, indicating additional susceptibility factors for BCR. Discovery of HLA class I-specific killer cell immunoglobulin-like receptors (KIR) led to a series of epidemiological studies implicating KIR-HLA gene combinations in disease. Here, we characterized KIR-HLA pairs in BCR patients and controls carrying HLA-A*29 as well as controls lacking HLA-A*29. KIR-HLA pairs implicated for weak inhibition (KIR2DL2/3+HLA-C1 and KIR3DL1+HLA-Bw4(T80)) in combination with activating KIR genes associated with autoimmunity (KIR2DS2, 2DS3 and 2DS4) augment the risk of developing BCR in HLA-A*29-positive individuals. The reciprocal association of strong inhibitory pairs (KIR3DL1+HLA-Bw4(I80) and KIR2DL1+HLA-C2) in combination with those implicated in protection from infection (KIR3DS1+HLA-Bw4(I80) and KIR2DS1+HLA-C2) was observed in HLA-A*29-negative controls. These results suggest that a profound effect of KIR2DS2/S3/S4 in the absence of strong inhibition may enhance the activation of natural killer cells and T-cell subsets against intraocular self-antigens, thereby contributing to pathogenesis of BCR.

The taxane-enhancer STA-4783 induces Hsp70 expression and apoptosis via an oxidative stress mechanism

14107

Background: STA-4783 is an inducer of Hsp70 expression and apoptosis that recently completed a successful Phase II clinical trial in melanoma. In a double-blind, randomized, controlled trial in patients with Stage IV disease, STA-4783 plus paclitaxel doubled progression-free survival compared to paclitaxel alone (Perspectives in Melanoma X and the Third International Melanoma Research Congress, 2006). The mechanism by which STA-4783 synergizes with paclitaxel is not fully understood. To identify the major pathway modulated by STA- 4783 in vitro, a transcriptional profiling analysis of drug-treated melanoma cells was performed. Methods: Transcriptional profiling was performed on Hs294T and MDA-MB-435 melanoma cell lines treated with STA-4783. The induction of Hsp70 RNA and other human genes was monitored by Real Time-PCR (RT-PCR) analysis. Measurement of reactive oxygen species (ROS) was performed in human cells using the Carboxy-H2DCFDA probe. Levels of apoptotic cell death were determined by flow cytometry analysis using an Annexin V specific probe. Results: Transcriptional profiling revealed that STA-4783 induced the expression of numerous gene families known to be regulated by oxidative stress, including heat shock proteins and metallothioneins. STA-4783 induced the generation of ROS in cells resulting in the oxidation and activation of the Carboxy-H2DCFDA fluorescent probe. The antioxidants N-Acetyl Cysteine (NAC) and Tiron potently blocked the induction of Hsp70 RNA and apoptotic cell death. Conclusions: STA-4783 induces oxidative stress in cells resulting in Hsp70 induction and apoptotic cell death. Although STA-4783 initially induced a transient protective response, apoptotic cell death occurred due to sustained oxidative stress. Cancer cells produce more ROS than normal cells and are thus more sensitive to insults that induce oxidative stress. The induction of ROS in melanoma cells by STA-4783 may therefore enhance the efficacy of paclitaxel in vivo. STA-4783 belongs to a novel class of anticancer agents that induce cell death by pushing the cancer cell beyond its oxidative stress breaking point.

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Recognition and capture of breast cancer cells using an antibody-based platform in a microelectromechanical systems device

Cancer is one of the most common diseases afflicting humans. The use of biomarkers specific for tumor cells has facilitated their identification. However, technology has not kept pace with the field of molecular biomarkers, leaving their potential unrealized. Here, we demonstrate the efficacy of recognizing and capturing cancer cells using an antibody-based, on-chip, microfluidic device. A cancer cell capture biochip consisting of microchannels of size 2.0 cm long and 500 microm wide and deep, was etched onto Polydimethylsiloxane. Epithelial membrane antigen (EMA) and Epithelial growth factor receptor (EGFR) were coated on the inner surface of the microchannels. The overall chip measured 2.0 cm x 1.5 cm x 0.5 cm. Normal and tumor breast cells in a phosphate buffered saline (PBS) suspension were flowed through the biochip channels at a rate of 15 microL/min. Breast cancer cells were preferentially captured and identified while most of normal cells passed through. The capture rates for tumor and normal cells were found to be >30% and <5%, respectively. This preliminary cancer cell capture biochip design supports our initial effort of moving a BioMEMS device, from the bench top to the clinic.

A robot-assisted orthopedic telesurgery system

A robot-assisted orthopedic telesurgery system, named HIT-RAOTS, has been developed according to Chinese conventional operation method. Its main function includes obtaining images with information of position and orientation of fracture, providing fracture information for doctors, assisting the doctors to complete the reposition of fracture and locking operation of intramedullary nail. In this system, a 6-dof force-reflecting master device, with a pantographic parallelogram mechanisms driven by harmonic DC servomotors, is used to control the slave manipulator movement and to translate the force from the operating room to the surgeon console; A slave robot system integrated a 6-dof force sensor, with a parallel manipulator actuated by six AC servomotors, is applied for the accurate repositioning; A virtual simulation system and human-machine interface are also developed. PI controller based on local network is used to realize the teleoperation. Only little irradiation is issued during the reposition. It can assist surgeons to perform bone-setting more safely by reducing irradiation damage to both surgeries and patients, more easily by releasing the surgeons from the heavy operation and more perfect by improving accuracy of reposition.

Microfluidic-based diagnostics for cervical cancer cells

The use of biomarkers has facilitated the detection of specific tumor cells. However, the technology to apply these markers in a clinical setting has not kept pace with their increasing availability. In this project, we use an antibody-based microfluidics platform to recognize and capture cervical cancer cells. Because HPV-16 infection of cervical cells and up-regulation of alpha6-integrin cell surface receptors are correlated, we utilized alpha6-integrin as a capture antibody bound to the channel surface. Normal human glandular epithelial cells (HGEC), human cervical stromal cells (HCSC) and cervical cancer cells (HCCC) were suspended in PBS and flowed through the system. Greater than 30% of the cancer cells were captured while the capture of the normal cell types was less than 5%. The technique is sensitive and accurate. It is potentially useful in the detection of cervical cancer at all stages, as well as other of cancers with similar characteristics of cell surface antigen expression.

Antimicrobial activity of essential oils and structurally related synthetic food additives towards selected pathogenic and beneficial gut bacteria

AIMS

To assess the potential of essential oils and structurally related synthetic food additives in reducing bacterial pathogens in swine intestinal tract.

METHODS AND RESULTS

The antimicrobial activity of essential oils/compounds was measured by determining the inhibition of bacterial growth. Among 66 essential oils/compounds that exhibited > or =80% inhibition towards Salmonellatyphimurium DT104 and Escherichia coli O157:H7, nine were further studied. Most of the oils/compounds demonstrated high efficacy against S. typhimurium DT104, E. coli O157:H7, and E. coli with K88 pili with little inhibition towards lactobacilli and bifidobacteria. They were also tolerant to the low pH. When mixed with pig cecal digesta, these oils/compounds retained their efficacy against E. coli O157:H7. In addition, they significantly inhibited E. coli and coliform bacteria in the digesta, but had little effect on the total number of lactobacilli and anaerobic bacteria.

CONCLUSIONS

Some essential oils/compounds demonstrated good potential, including efficacy, tolerance to low pH, and selectivity towards bacterial pathogens, in reducing human and animal bacterial pathogens in swine intestinal tract.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study has identified candidates of essential oils/compounds for in vivo studies to develop antibiotic substitutes for the reduction of human and animal bacterial pathogens in swine intestinal tract.

The phylogeny of Chinese indigenous pig breeds inferred from microsatellite markers

A genetic study of 32 local Chinese, three foreign pig breeds [Duroc (DU), Landrace and Yorkshire], and two types of wild boar (Hainan and Dongbei wild boar) based on 34 microsatellite loci was carried out to clarify the phylogeny of Chinese indigenous pig breeds. The allele frequencies, effective numbers of alleles, and the average heterozygosity within populations were calculated. The results showed that the genetic variability of the Lingao pig was the largest, while the Jiaxing pig was the lowest. The greatest distance between domestic pigs was found between Shanggao and DU pig and the shortest was found between Wuzhishan and Lingao pig, respectively. A neighbour-joining tree constructed from Modified Cavalli-Sforza genetic distances divided Chinese pigs into two clusters; four subclusters were also identified. Our results only partly agree with the traditional types of classification and also provide a new relationship among Chinese local pig breeds. Our data also confirmed that Chinese pig breeds have a different origin from European/American breeds and can be utilized in programmes that aim to maintain Chinese indigenous pig breeds.