miRNA-34a suppresses cell proliferation and metastasis by targeting CD44 in human renal carcinoma cells

PURPOSE

We investigated the potential functions of miR-34a in CD44 transcriptional complexes in renal cell carcinoma.

MATERIALS AND METHODS

We detected miR-34a expression by quantitative real-time polymerase chain reaction. Oligonucleotides were used to over express miR-34a. Cell proliferation and xenograft assays, colony formation and flow cytometry were done to examine effects on cancer cell proliferation in vitro and in vivo. Luciferase assay was performed to verify the precise target of miR-34a.

RESULTS

Promoter methylation contributed to miR-34a loss in the ACHN, 786-O and SN12PM6 renal carcinoma cell lines. Ectopic over expression of miR-34a restrained cell growth, tube formation and migration/invasion, and significantly suppressed the growth of renal carcinoma xenografts and metastasis in nude mice. Dual luciferase assay revealed that CD44 was a direct target of miR-34a in renal cancer cells and CD44 knockdown by RNAi in renal cancer cells suppressed tumor progression. In contrast, CD44 ectopic expression partially reversed the antitumor effects of miR-34a in renal cancer cells.

CONCLUSIONS

Our findings indicate that miR-34a targets CD44 in renal cancer cells and suppresses renal cancer cell growth, tube formation and metastasis in vitro and in vivo. Thus, miR-34a may be a potential molecular target for novel therapeutic strategies for clear cell renal carcinoma.

Similar survival, but better quality of life after myeloablative transplantation using unrelated cord blood vs matched sibling donors in adults with hematologic malignancies

This study included data from 185 consecutively treated patients, 16 years of age or older, who underwent myeloablative transplantation using unrelated umbilical cord blood (UCB) (UCB transplantation (UCBT), n=70) or HLA-identical sibling donor peripheral blood stem cells alone or combined with bone marrow (BMT/PBSCT, n=115) from October 2001 to December 2012. All patients received myeloablative regimens, cyclosporin A plus mycophenolate mofetil as prophylaxis for GVHD, and similar supportive care. Although hematopoietic recovery was significantly delayed after UCBT, the rate of neutrophil engraftment was comparable. The median follow-up was 53 months (range, 15-136 months) for BMT/peripheral blood SCT (PBSCT) recipients and 35 months (range, 10-123 months) for UCBT recipients. There were no significant differences in the cumulative incidence of grades III to IV acute GVHD, relapse rate, or 3-year probabilities of disease-free survival between patients receiving UCBT and those receiving BMT/PBSCT. However, the cumulative incidence of chronic and extensive chronic GVHD was lower in UCBT recipients. The rates of long-term survivors returning to school or work and off immunosuppressive therapy were significantly higher after UCBT, which indicated that long-term survivors who underwent UCBT had a higher quality of life.

Profilin1 sensitizes pancreatic cancer cells to irradiation by inducing apoptosis and reducing autophagy

Pancreatic cancer has an extremely poor prognosis mainly due to lack of effective treatment options. Radiotherapy is mostly applied to locally advanced cases, although tumor radioresistance limits the effectiveness. Profilin1, a novel tumor suppressor gene, was reported to be down-regulated in various cancers and associated with tumor progression. The objective of this study was to demonstrate how profilin1 affected pancreatic cancer radiosensitivity. We showed profilin1 was down-regulated in pancreatic cancer cells after exposure to radiation, and re-expression of profilin1 suppressed tumor cell viability and increased DNA damage following irradiation. Further studies revealed that up-regulation of profilin1 facilitated apoptosis and repressed autophagy induced by irradiation, which might sensitize pancreatic cancer cells to radiation treatment. Our findings may provide a novel therapeutic strategy for sensitizing pancreatic cancer to radiotherapy.

Analysis of hepatitis B virus intrahepatic covalently closed circular DNA and serum viral markers in treatment-naive patients with acute and chronic HBV infection

Background

This study aimed to investigate the relationships of intrahepatic cccDNA with serum HBsAg and with HBV DNA in treatment-naive patients throughout acute and chronic HBV infection.

Methods

A total of 120 patients who had a liver biopsy were enrolled, including 19 with acute hepatitis B (AHB), and 101 patients with chronic HBV infection (CHB) of whom were 10 in immune-tolerant (IT) phase, 59 in immune-clearance (IC) phase, 8 in low-replicative (LR) phase, and 24 in HBeAg-negative hepatitis (ENH) phase. Intrahepatic cccDNA, serum HBsAg and serum HBV DNA levels were comparatively analyzed.

Results

The median intrahepatic cccDNA levels were 0.18 4.80, 3.81, 0.22 and 0.97 copies/cell for patients with AHB, CHB-IT, CHB-IC, CHB-LR, and CHB-ENH, respectively. In AHB patients, intrahepatic cccDNA was positively correlated with serum HBsAg (r = 0.665, P = 0.003), as well as serum HBV DNA (r = 0.536, P = 0.022). In CHB patients, intrahepatic cccDNA was positively correlated with serum HBsAg in the IC phase (r = 0.392, P = 0.005), and with serum HBV DNA in the IC phase (r = 0.301, P = 0.036) and ENH phase (r = 0.588, P = 0.013). HBV replicative efficiency, defined as the ratio of serum HBV DNA to intrahepatic cccDNA, was obviously lower in AHB and CHB-LR patients than in CHB-IT, CHB-IC and CHB-ENH patients (0.70 and 0.53 vs. 1.12, 1.09 and 0.99, P<0.001, values were logarithmic transformed for analysis). In CHB-IC patients, HBV replicative efficiency was positively correlated with histological activity index of liver inflammation (r = 0.308, P = 0.009).

Conclusion

Serum HBsAg and HBV DNA levels may reflect the amount of active intrahepatic cccDNA in treatment-naive AHB and CHB-IC patients. Reduced intrahepatic cccDNA and HBV replicative efficiency may imply effective immune control of HBV infection.

MicroRNA-191 correlates with poor prognosis of colorectal carcinoma and plays multiple roles by targeting tissue inhibitor of metalloprotease 3

MicroRNA-191 (miR-191) is reported to be overexpressed in colorectal carcinoma (CRC), but the role of miR-191 in CRC progress remained unclear. This study demonstrated that High miR-191 expression was associated with clinical stage, lymph node metastasis, liver metastasis and depth of tumor invasion. Kaplan-Meier analysis indicated that patients with high miR-191 expression had a poor overall survival. Moreover, multivariate analysis showed that miR-191 was an independent prognostic factor in patients with CRC. Furthermore, we found that tissue inhibitor of metalloprotease 3 (TIMP3) was a direct target of miR-191 in colorectal cancer SW620 cells. TIMP3 downregulation mediated by miR-191 activated matrix metalloproteinases (MMPs) and thus promoted invasiveness of cancer cells. Anti-miR-191 could attenuate the invasiveness, suppress proliferation and induce apoptosis by restoring TIMP3 expression. Our results suggested that miR-191 might be a potential diagnostic and therapeutic target in patients with colorectal cancer.

Meta-analysis of long-term vitamin D supplementation on overall mortality

Introduction

It has been suggested that vitamin D is effective to prevent mortality. However, there is no consistent conclusion that the effects of vitamin D supplementation on all-cause mortality are associated with duration of treatment. We conducted a meta-analysis regarding this issue in an effort to provide a more robust answer.

Methods

A comprehensive search in a number of databases, including MEDLINE, Embase and The Cochrane Central Register of Controlled Trials, was conducted for collecting randomized controlled trials (RCTs) on vitamin D supplementation preventing mortality. Two investigators independently screened the literature according to the inclusive and exclusive criteria and the relative data were extracted. Data analysis was performed by using Review Manager 5.0 software.

Results

Data from forty-two RCT s were included. Vitamin D therapy significantly decreased all-cause mortality with a duration of follow-up longer than 3 years with a RR (95% CI) of 0.94 (0.90–0.98). No benefit was seen in a shorter follow-up periods with a RR (95% CI) of 1.04 (0.97–1.12). Results remain robust after sensitivity analysis. The following subgroups of long-term follow-up had significantly fewer deaths: female only, participants with a mean age younger than 80, daily dose of 800 IU or less, participants with vitamin D insufficiency (baseline 25-hydroxyvitamin D level less than 50 nmol/L) and cholecalciferol therapy. In addition, the combination of vitamin D and calcium significantly reduced mortality and vitamin D alone also had a trend to decrease mortality in a longer time follow up.

Conclusions

The data suggest that supplementation of vitamin D is effective in preventing overall mortality in a long-term treatment, whereas it is not significantly effective in a treatment duration shorter than 3 years. Future studies are needed to identify the efficacy of vitamin D on specific mortality, such as cancer and cardiovascular disease mortality in a long-term treatment duration.

Antidepressant drug, desipramine, alleviates allergic rhinitis by regulating Treg and Th17 cells

Allergic rhinitis (AR) is characterized by IgE-mediated immediate hypersensitivity and usually progresses to chronic nasal inflammation, with depression as one of its comorbidities. The importance of treating the depression in AR patients has been increasingly recognized. Desipramine is a representative of tricyclic-antidepressant agents. In the present study we investigate whether desipramine has therapeutic effects on AR inflammation. BALB/C mice were sensitized by intraperitoneal injection of ovalbumin (OVA), followed by repeated challenge with OVA intranasally. Desipramine was administered orally to treat the mice. The nasal symptoms (sneezing, nasal scratching etc.) of AR were evaluated to determine the severity of AR. Cytokines in the nasal lavage fluid (NALF), including interferon-gamma (IFN-gamma), interleukin 4 (IL-4) and serum OVA-specific immunoglobulin E (IgE) antibody were measured by ELISA. The regulatory T cells (Treg) and T helper cells 17 (Th17) were quantified by flow cytometric analysis. As a result, the repeated oral administration of desipramine attenuated the nasal symptoms (sneezing and nasal rubbing) in AR mice. Desipramine also suppressed the serum OVA-specific IgE and IL-4 levels, but had no effect on IFN-gamma level. Moreover, desipramine treatment up regulated CD4+CD25+Foxp3+ Treg cells, which were found down-regulated in established AR mice. Meanwhile, desipramine administration attenuated CD4+IL-17+ Th17 cells, which were significantly increased in AR mice. These results suggest that the antidepressant drug, desipramine, also has anti-allergic action, which was possibly achieved by reducing allergen-specific IgE and Th2 cytokine production and maintaining a balance between Treg and Th17 cells. Thus, this study provide the first evidence that desipramine may be utilized to treat allergic diseases, especially for those allergic patients with depression or depression patients with allergy.

Gene profile identifies zinc transporters differentially expressed in normal human organs and human pancreatic cancer

Deregulated expression of zinc transporters was linked to several cancers. However, the detailed expression profile of all human zinc transporters in normal human organs and in human cancer, especially in pancreatic cancer is not available. The objectives of this study are to investigate the complete expression patterns of 14 ZIP and 10 ZnT transporters in a large number of normal human organs and in human pancreatic cancer tissues and cell lines. We examined the expression patterns of ZIP and ZnT transporters in 22 different human organs and tissues, 11 pairs of clinical human pancreatic cancer specimens and surrounding normal/benign tissues, as well as 10 established human pancreatic cancer cell lines plus normal human pancreatic ductal epithelium (HPDE) cells, using real time RT-PCR and immunohistochemistry. The results indicate that human zinc transporters have tissue specific expression patterns, and may play different roles in different organs or tissues. Almost all the ZIPs except for ZIP4, and most ZnTs were down-regulated in human pancreatic cancer tissues compared to the surrounding benign tissues. The expression patterns of individual ZIPs and ZnTs are similar among different pancreatic cancer lines. Those results and our previous studies suggest that ZIP4 is the only zinc transporter that is significantly up-regulated in human pancreatic cancer and might be the major zinc transporter that plays an important role in pancreatic cancer growth. ZIP4 might serve as a novel molecular target for pancreatic cancer diagnosis and therapy.

MicroRNA-34b inhibits pancreatic cancer metastasis through repressing Smad3

Pancreatic cancer is characterized by extremely poor prognosis because of early recurrence and metastasis, and increasing evidence supports the critical role of microRNA in cancer progression. Here we identified that microRNA-34b functioned as a tumor-suppressing microRNA by targeting oncogenic Smad3 in pancreatic cancer. As a hypovascular tumor with a potential endoplasmic reticulum stress microenvironment, miR-34b was silenced after ER stress inducer thapsigargin (Tg) treatment and negatively regulated by ER stress chaperone glucose regulated protein 78 (GRP78) in pancreatic cancer cells. In human specimens, we found that miR-34b was down-regulated in pancreatic cancer tissues and low level of miR-34b expression was positively correlated with tumor-node-metastasis (TNM) stage, lymph-node metastasis and overall survival. Functional assays showed that over-expression of miR-34b inhibited pancreatic cancer progression in vitro and in vivo. In addition, Smad3 was demonstrated as a direct target of miR-34b and negatively regulated by miR- 34b at mRNA and protein levels. Luciferase assays confirmed that miR-34b could directly bind to the 3'untranslated region of Smad3. An inverse correlation between miR-34b and Smad3 was observed in 64 pancreatic cancer tissues. Our findings indicate that miR-34b acts as a tumor metastasis suppressor through negatively modulating Smad3, which may provide a potential therapeutic strategy for pancreatic cancer.

Profilin 1 potentiates apoptosis induced by staurosporine in cancer cells

The correlation between the loss of Profilin 1 (Pfn1) with tumor progression indicated that Pfn1 is a tumor suppressor in human carcinoma. The molecular mechanisms underlying Pfn1 tumor suppression has yet to be elucidated. In this study, we showed that Pfn1 overexpression sensitizes cancer cells to apoptosis through the typical intrinsic apoptotic pathway. Mechanistically, the increased Pfn1 expression mediated the upregulation of p53R273H, one of the most common tumor-associated hotspot mutations of p53, with transactivation deletion in tumorigenesis and increased localization of p53R273H in cytoplasm. Further studies showed that mutant p53R273H was involved in apoptosis induced by Staurosporine (STS) via transcription-independent mitochondrial functions. We observed (i) the increased cytosolic localization of p53R273H, (ii) the activation of phosphorylation at Ser15, (iii) its mitochondrial localization; Pfn1 acted as a positive regulator of these processes. We also found that Pfn1 interacted with p53R273H and thus facilitated its exertion over the transcription-independent activity in the cytoplasm during drug action. Our results define a new function and mechanism of Pfn1 demonstrating that the combined effect with apoptotic agents led to a synergistic increase in apoptosis. In addition, p53R273H abrogating DNA binding was found to play a major role in the Pfn1- sensitized apoptosis through a transactivation-independent and cytosolic activity.

Up-regulation of MBD1 promotes pancreatic cancer cell epithelial-mesenchymal transition and invasion by epigenetic down-regulation of E-cadherin

Methyl-CpG binding domain protein 1 (MBD1) has been implicated in transcriptional regulation, heterochromatin formation, genomic stability, cell-cycle progression and development. It is also predicted that MBD1 might be involved in tumor development and progression. However, whether and how MBD1 is involved in tumorigenesis, especially in pancreatic cancer (PC), is currently unknown. We found that MBD1 was significantly up-regulated in PC tissues compared with the surrounding normal tissues according to RT-PCR data. Tissue microarray (TMA) based immunohistochemical study from 58 surgically resected PC specimens indicated that higher MBD1 expression correlated with lymph node metastasis and poor survival in PC patients. Gain- and loss-of-function studies in vitro validated MBD1 as a potent oncogene promoting PC cell invasion as well as epithelial-mesenchymal transition (EMT). Mechanistically, MBD1 is associated with Twist and NAD-dependent deacetylase sirtuin-1 (SIRT1), thereby forming the Twist-MBD1-SIRT1 complex on the CDH1 promoter, which resulted in reduced E-cadherin transcription activity and increased cell EMT ability. Significantly, targeting MBD1 reversed the EMT phenotype of PC and restored sensitivity to chemotherapy. Taken together, the results of our study revealed a novel function of MBD1 in PC invasion and metastasis by providing a molecular mechanism underlying MBD1-promoted EMT. Thus MBD1 may serve as a potential therapeutic target for PC.

LncRNAs expression signatures of renal clear cell carcinoma revealed by microarray

Background

Long noncoding RNAs (lncRNAs) are an important class of pervasive genes involved in a variety of biological functions. They are aberrantly expressed in many types of cancers. In this study, we described lncRNAs profiles in 6 pairs of human renal clear cell carcinoma (RCCC) and the corresponding adjacent nontumorous tissues (NT) by microarray.

Methodology/Principal Findings

With abundant and varied probes accounting 33,045 LncRNAs in our microarray, the number of lncRNAs that expressed at a certain level could be detected is 17157. From the data we found there were thousands of lncRNAs that differentially expressed (≥2 fold-change) in RCCC tissues compared with NT and 916 lncRNAs differentially expressed in five or more of six RCCC samples. Compared with NT, many lncRNAs were significantly up-regulated or down-regulated in RCCC. Our data showed that down-regulated lncRNAs were more common than up-regulated ones. ENST00000456816, X91348, BC029135, NR_024418 were evaluated by qPCR in sixty-three pairs of RCCC and NT samples. The four lncRNAs were aberrantly expressed in RCCC compared with matched histologically normal renal tissues.

Conclusions/Significance

Our study is the first one to determine genome-wide lncRNAs expression patterns in RCCC by microarray. The results displayed that clusters of lncRNAs were aberrantly expressed in RCCC compared with NT samples, which revealed that lncRNAs differentially expressed in tumor tissues and normal tissues may exert a partial or key role in tumor development. Taken together, this study may provide potential targets for future treatment of RCCC and novel insights into cancer biology.

Comparative fasting bioavailability and pharmacokinetic properties of 2 formulations of glucosamine hydrochloride in healthy Chinese adult male volunteers

Glucosamine (CAS 66-84-2) hydrochloride is an amino monosaccharide indicated for the treatment of arthrosis, especially osteoarthritis of the knee joint. This study was conducted to assess and compare the pharmacokinetic (PK) properties, bioavailability of a newly developed dispersible tablet formulation (test) of glucosamine hydrochloride with those of an established branded capsule formulation (reference) in healthy Chinese adult male volunteers.This single-dose, randomized, open-label, 2-period crossover study was conducted in 18 healthy Chinese adult male volunteers under fasting condition. Plasma samples were collected at pre-specified times over a 12-h period following administration in each period and analyzed the plasma glucosamine concentrations by Liquid Chromatography coupled with Tandem Mass Spectrometry (LC/MS/MS) method. The mean (SD) PK parameters of Cmax, Tmax, AUC0-12, and AUC0-∞ after administration of the test and reference formulations were, respectively, as follows: Cmax, 907.01 (444.22) vs. 944.40 (429.89) ng/mL, Tmax, 3.03 (0.95) vs. 3.30 (0.99) hours, AUC0-12, 2891.41 (1352.30) vs. 2889.69 (925.48) ng/mL/h, and AUC0-∞, 3029.90 (1321.36) vs. 3091.87 (870.36) ng/mL/h. The mean (SD) t1/2 was 1.10 (0.52) hours for the test formulation and 1.50 (1.17) hours for the reference formulation. On ANOVA, neither period nor sequence effects were observed for any PK properties. The relative bioavailability of the test formulation was 98.3% assessed by AUC0-12. The 90% CIs of glucosamine for the log-transformed ratios of Cmax, AUC0-12, and AUC0-∞ were 78.4-113.9%, 80.8-108.5% and 80.8-105.8%, respectively, meeting the predetermined criteria for bioequivalence of SFDA.

SU-E-J-205: Modeling Fiducial Marker Movement in Prostate

PURPOSE

To understand fiducial marker movement in prostate and to improve prostate patient positioning with fiducial markers.

METHODS

Patient planning CT and positioning CBCT were retrospectively analyzed. CBCT images were automatically registered to the corresponding CT ones based on their bony structures in Eclipse. The coordinates of the markers in the CT and CBCT were recorded. The status of bladder and rectum fillings, and gas in rectum were indexed into four levels and recorded. An algorithm was developed to optimally register the (three) fiducial markers in CBCT with those in the CT so that only the information on prostate deformation and marker migration remained. A mathematical model was built to estimate the marker migration and the relative contribution to the deformation from the status change of bladder and rectum.

RESULTS

The registration error from our optimal registration algorithm indicates the minimal patient setup error by using fiducial markers. The results from our analyzed 3 patients were average(standard deviation) = 1.10(0.40), 1.27(0.67) and 0.62(0.38) mm, but there were some fractions when the registration errors were over 2 mm. From our mathematical model, it was found that the marker migration could be as large as 2.9 mm. If 2 mm tolerance is required in such as SBRT, then soft tissue based registration may be more appreciated when the optimal registration error is greater than 2 mm or from the date when the migration is greater than 2 mm because the migrated marker may not change the location thereafter. In addition, for one investigated patient, the relative contribution to the deformation from the bladder, rectum filling and gas in the rectum is 0.43:0.31:0.26. More patient data are in analysis, and other interesting results will be reported.

CONCLUSIONS

Fiducial marker migration can be over 2 mm. The migration will Result in a conclusion that small registration error does not mean good patient positioning.

Changes in cortical bone response to high-fat diet from adolescence to adulthood in mice

Diabetic obesity is associated with increased fracture risk in adults and adolescents. We find in both adolescent and adult mice dramatically inferior mechanical properties and structural quality of cortical bone, in agreement with the human fracture data, although some aspects of the response to obesity appear to differ by age.

INTRODUCTION

The association of obesity with bone is complex and varies with age. Diabetic obese adolescents and adult humans have increased fracture risk. Prior studies have shown reduced mechanical properties as a result of high-fat diet (HFD) but do not fully address size-independent mechanical properties or structural quality, which are important to understand material behavior.

METHODS

Cortical bone from femurs and tibiae from two age groups of C57BL/6 mice fed either HFD or low-fat diet (LFD) were evaluated for structural and bone turnover changes (SEM and histomorphometry) and tested for bending strength, bending stiffness, and fracture toughness. Leptin, IGF-I, and non-enzymatic glycation measurements were also collected.

RESULTS

In both young and adult mice fed on HFD, femoral strength, stiffness, and toughness are all dramatically lower than controls. Inferior lamellar and osteocyte alignment also point to reduced structural quality in both age groups. Bone size was largely unaffected by HFD, although there was a shift from increasing bone size in obese adolescents to decreasing in adults. IGF-I levels were lower in young obese mice only.

CONCLUSIONS

While the response to obesity of murine cortical bone mass, bone formation, and hormonal changes appear to differ by age, the bone mechanical properties for young and adult groups are similar. In agreement with human fracture trends, adult mice may be similarly susceptible to bone fracture to the young group, although cortical bone in the two age groups responds to diabetic obesity differently.

Encoding a superantigen by Staphylococcus aureus does not affect clinical characteristics of infected atopic dermatitis lesions

BACKGROUND

Bacterial infection with Staphylococcus aureus is a known trigger for the worsening of atopic dermatitis (AD). Staphylococcal superantigens have been theorized to make a potential contribution to this worsening of AD seen with infection.

OBJECTIVES

We sought to assess whether encoding a superantigen by S. aureus affects the inflammatory characteristics of impetiginized AD skin lesions.

METHODS

Fifty-two children with clinically impetiginized lesions of AD which were positive for S. aureus were enrolled in this study. A lesion was graded clinically using the Eczema Area and Severity Index (EASI), and then wash fluid was obtained from the lesion for quantitative bacterial culture, and measurement of bacterial products lipoteichoic acid and staphylococcal protein A and cytokines. The staphylococcal isolate was tested for antibiotic susceptibilities and the presence of a superantigen.

RESULTS

Fifty-four per cent (28 of 52) of the staphylococcal isolates encoded a superantigen. The presence of a superantigen had no significant effect on EASI score, amounts of bacterial products or inflammatory cytokines in the AD lesion.

CONCLUSIONS

These studies suggest that the expression of a superantigen by S. aureus alone does not play an important role in the increased skin inflammation associated with staphylococcal infection in childhood AD.

Two HTS options for a 600 MHz insert of a 1.3 GHz LTS/HTS NMR magnet: YBCO and BSCCO

In 2008, the Phase 3 program to complete a 1.3 GHz (30.5 T) NMR magnet started at the Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology. It comprises two sub-phases, 3A and 3B. In Phase 3A, a 600 MHz high temperature superconductor (HTS) insert magnet (H600) will be designed, constructed, and operated in the bore of a 500 MHz low temperature superconductor (LTS) background magnet. This will be followed by Phase 3B, in which the H600 will be combined with a 700 MHz LTS background magnet to complete a 1.3 GHz NMR LTS/HTS magnet. This paper presents and discusses design issues for two conductor options for H600: BiSCCO-2223 (Bi2223) and coated-YBCO or its variants, here designated as YBCO. For each conductor option, we focused on the following issues: 1) elastic and thermal properties; 2) critical current vs. field performance; 3) splice and index heat dissipations; 4) mechanical and thermal stresses; and 5) protection.

An Inhibitor of ADAMs (a Distintegrin and Metalloproteinase) Overcomes HER3-Mediated Resistance to Trastuzumab and Lapatinib

Background: Inhibitors of HER-2/neu and EGF receptors such as trastuzumab, lapatinib, and erlotinib have demonstrated clinical efficacy but not all HER-2/neu or EGFR positive tumors respond and many that initially respond develop resistance. Ligand mediated HER-3 signaling results in tumor growth and survival and is a proposed mechanism of resistance to trastuzumab and lapatinib. Proteolytic cleavage of both ErbB ligands and receptors has been shown to be a critical event that results in ErbB pathway activation. Cleavage is necessary for the generation of soluble, functionally active forms of ErbB ligands and in the case of HER-2/neu, cleavage results in a shed extracellular domain (ECD) and a membrane bound fragment (p95) that contains a kinase domain with significant constitutive activity. In addition, it has been shown that the preferential association between HER3 and p95 can further activate the pathway. Both ErbB ligand and HER-2/neu cleavage are mediated by the ADAM family of proteases. Further, we have previously shown that the ADAM protease inhibitor, INCB7839, provides synergistic inhibition of HER2+ breast cancer cell line growth when combined with either trastuzumab or lapatinib. Materials and Methods: The HER-2 overexpressing BT-474 human breast cancer cell line was treated with either lapatinib or trastuzumab in the presence or absence of the HER-3 ligand, heregulin, and the effects on cell growth measured. The effects of the ADAM protease inhibitor INCB7839 in this system were also examined. Results: The addition of heregulin overcame the anti-proliferative effects of both lapatinib and trastuzumab on the growth of the BT-474 cell line in vitro. Addition of INCB7839 synergized with lapatinib or trastuzumab and importantly, restored the anti-proliferative effects of these agents in the presence of heregulin. Further, pretreatment of BT-474 cells with INCB7839 for 6 days, which we have previously shown completely eliminates the presence of the p95 form of HER2, amplified these effects, presumably by eliminating p95 before stimulating the cells with heregulin. Discussion: Together, these results confirm that heregulin can overcome the anti-proliferative effects of both trastuzumab and lapatinib as previously reported. Prevention of p95 formation by ADAM protease inhibitors appears to restore the anti-proliferative effects of both trastuzumab and lapatinib when heregulin/HER3 signaling occurs, negating a proposed mechanism of resistance to these agents in the clinic. These results suggest that combining an ADAM inhibitor with targeted inhibitors of the ErbB family can overcome HER-3-mediated resistance and enhance the clinical efficacy of approved HER2-targeted agents in the clinical setting. INCB7839 is currently under clinical investigation in combination with trastuzumab for women with metastatic breast cancer.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3138.

COPD in Chinese nonsmokers

Little is known about chronic obstructive pulmonary disease (COPD) in Chinese nonsmokers. The present study aimed to investigate the profiles of COPD among nonsmokers based on the Chinese Epidemiological Survey of COPD (CESCOPD). In the CESCOPD, 20,245 subjects aged 40 yrs or older were interviewed with questionnaires and spirometry tests. Subjects with a post-bronchodilator forced expiratory volume in one second (FEV(1))/forced vital capacity (FVC) ratio of <0.70 were identified as having COPD. Data of 12,471 nonsmokers and 1,024 smoking COPD patients were analysed in the current study. The overall prevalence of COPD among nonsmokers was 5.2% (95% confidence interval 4.8-5.6). Being male, of advanced age, lower body mass index (BMI) and lower educational level, having exposure to environmental tobacco smoke, coal and/or biomass smoke, poor ventilation in the kitchen, a family history of respiratory disease and recurrent childhood cough were all independently associated with a higher risk of having COPD among nonsmokers. Nonsmokers with respiratory symptoms without airflow limitation showed a somewhat different pattern of risk factors. Nonsmokers with COPD were less likely to present with chronic productive coughs and lower BMI, while more likely to have received a physician diagnosis of asthma and respiratory diseases in childhood, than smokers with COPD. Chronic obstructive pulmonary disease is prevalent among Chinese nonsmokers, and nonsmoking chronic obstructive pulmonary disease may have different profiles from smoking chronic obstructive pulmonary disease.

Meta- and pooled analyses of the effect of glutathione S-transferase M1 and T1 deficiency on chronic obstructive pulmonary disease

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a complex polygenic disease in which gene-environment interactions are very important. A number of studies have investigated the genotypes of glutathione S-transferase M1 and T1 (GSTM1 and GSTT1) in relation to COPD susceptibility in different populations. However, the results of individual studies have been inconsistent.

METHODS

To address the inconsistent findings in studies of the association of the polymorphism of the GSTM1 and GSTT1 genes with susceptibility to COPD, we performed a meta-analysis of the published data. We searched the Medline database for case-control studies published from 1966 to July 2008. Data were extracted and pooled, and ORs were calculated with their 95%CIs.

RESULTS

Twelve eligible studies comprising 1697 patients with COPD and 1867 controls were included in the meta-analysis. The pooled result showed that the GSTM1 deficiency was associated with risk of COPD (OR 1.46, 95%CI 1.16-1.83). Subgroup analysis supported the results in smoking and non-Asian populations, but not in Asian populations. The GSTT1 deficiency was not associated with risk of COPD.

CONCLUSIONS

The GSTM1 gene is a genetic contributor to overall COPD susceptibility in non-Asian populations, and the GSTT1 gene is not associated with COPD.

Measurement of the toughness of bone: a tutorial with special reference to small animal studies

Quantitative assessment of the strength and toughness of bone has become an integral part of many biological and bioengineering studies on the structural properties of bone and their degradation due to aging, disease and therapeutic treatment. Whereas the biomechanical techniques for characterizing bone strength are well documented, few studies have focused on the theory, methodology, and various experimental procedures for evaluating the fracture toughness of bone, i.e., its resistance to fracture, with particular reference to whole bone testing in small animal studies. In this tutorial, we consider the many techniques for evaluating toughness and assess their specific relevance and application to the mechanical testing of small animal bones. Parallel experimental studies on wild-type rat and mouse femurs are used to evaluate the utility of these techniques and specifically to determine the coefficient of variation of the measured toughness values.

Change in serum measurements of cartilage oligomeric matrix protein and association with the development and worsening of radiographic hip osteoarthritis

OBJECTIVE

To determine the association between changes in serum levels of cartilage oligomeric matrix protein (COMP) and serum N-telopeptide crosslinks (NTX) over a 6-year interval with the development and progression of radiographically apparent hip osteoarthritis (RHOA) in a community sample of elderly women over 8.3 years of follow-up.

METHODS

Pelvic radiographs were obtained a mean of 8.3 years apart in Caucasian women > or =65 years of age enrolled in the Study of Osteoporotic Fractures. From a cohort of 5928 subjects, we randomly sampled study subjects ( approximately 170 per group) to perform two nested case-control studies, one of RHOA incidence and the other of RHOA progression. Baseline and year 6 serum COMP and serum NTX levels were measured by enzyme linked immunosorbent assay in duplicate and percentage change in serum levels was calculated. Odds ratios (ORs) and 95% confidence intervals (CIs) for 1 standard deviation (SD) change in the serum COMP and NTX level differences were calculated using logistic regression analysis and used to predict the development or progression of RHOA, adjusting for potential covariates.

RESULTS

The percentage change in the level of serum COMP from baseline to year 6 was found to be a risk factor for the development of incident RHOA [adjusted OR of 1.58 per 1 SD increase (95% CI: 1.19-2.09)], and reduction of progression of RHOA [adjusted OR of 0.74 per 1 SD increase (95% CI: 0.58-0.96)]. Quartile analysis of serum COMP changes revealed that the three highest quartiles of change in serum COMP were associated with (1) a five-fold greater risk of developing incident RHOA [adjusted OR=5.42 (95% CI: 2.80-10.60)], and (2) a 50% decreased risk of developing progression of RHOA [adjusted OR=0.48 (95% CI: 0.30-0.80)]. No significant association was found between changes in serum NTX levels from baseline to year 6 with either incident RHOA or the progression of existing RHOA.

CONCLUSION

Measurement of serum COMP at two distinct timepoints may be a method of identifying patients at risk for developing incident RHOA and those with baseline RHOA that will not rapidly progress.