Construction of a New Fusion Anti-caries DNA Vaccine

Mutans streptococci (MS) are generally considered to be the principal etiological agent of dental caries. MS have two important virulence factors: cell- surface protein PAc and glucosyltransferases (GTFs). GTFs have two functional domains: an N-terminal catalytic sucrose-binding domain (CAT) and a C-terminal glucan-binding domain (GLU). A fusion anti-caries DNA vaccine, pGJA-P/VAX, encoding two important antigenic domains, PAc and GLU, of S. mutans, was successful in reducing the levels of dental caries caused by S. mutans in gnotobiotic animals. However, its protective effect against S. sobrinus infection proved to be weak. Does the DNA vaccine need an antigen of S. sobrinus to enhance its ability to inhibit infection? To answer this question, in this study, we cloned the catalytic ( cat) fragment of S. sobrinus gtf-I, which demonstrated its ability to inhibit water-insoluble glucan synthesis by S. sobrinus, into pGJA-P/VAX to produce a new anti-caries DNA vaccine.

Phase I dose-escalation study of thoracic radiotherapy in combination with gefitinib in patients with IIIB/IV non-small cell lung cancer (NCT00497250)

e14581

Background: Cinical studies have confirmed that gefitinib, an EGFR-TKI, is effective for some advanced NSCLC patients. Patients with Asian ethnicity are reported to have a higher response rate with gefitinib monotherapy. However, a higher incidence of interstitial lung disease, sometimes lethal, is also found. The combination of gefitinib and radiotherapy has been observed to have a synergistic, anti-proliferative effect against NSCLC in vitro. This phase I study assessed the safety, clinical feasibility and optimally tolerated regimen (OTR) of this combination in patients with pretreated locally advanced or metastatic (IIIB/IV) NSCLC. Methods: Patients with stage IIIB or selected stage IV, failure of platinum-based chemotherapy regimen NSCLC were eligible. Four Cohorts of eight patients each were planned to be treated with escalating doses from 54 to 60 Gy of conformal or intensity- modulated radiotherapy (2Gy/Fx) administered in combination with gefitinib 250mg daily during RT and 60 days after the completion of RT to determine the OTR. Results: Since June 2007, 2 cohorts, a total of 16 patients, were enrolled and treated: 8 stage IIIB and 8 stage IV; 2 squamous-cell carcinoma and 14 adenocarcinoma; 8 smokers and 8 nonsmokers. Prior-chemotherapy regimen was consisted of NP, GP and TP for a median of 3.5 cycles (range, 1–5). Median follow-up time was seven months. Mean progression-free survival time was 5.2 months (median, 3.9; range, 1.7–12.3). Overall, adverse events were mild to moderate in severity. The most frequent grade 2 events included pneumonitis (31%) and dysphagia (19%). There were one treatment-related grade 3 event, which was nausea, and no grade 4 events. Most of the failure patterns were out-of-field (11/13) and the most common distant metastasis organ was the lungs. Three patients are progression-free to date. Conclusions: Thoracic radiotherapy up to 56 Gy concurrent with gefitinib 250 mg daily was well tolerated and clinically active in this group of pretreated Chinese NSCLC patients, including nonsmokers with adenocarcinoma. Accrual is continuing. Sponsorship: This work was partly supported by Program for New Century Excellent Talents in University (NCET), Ministry of Education.

No significant financial relationships to disclose.

Involved-field radiotherapy for patients with limited small cell lung cancer: Patterns of local-regional failure and feasibility

7554

Background: To investigate the feasibility of the involved-field radiotherapy in patients with limited-stage small cell lung cancer (LSCLC) according to the patterns of local failure, focused on the first local-regional failure. Methods: Two clinical phase II studies for patients with LSCLC treated at our institute between 1997 and 2007 were reviewed. All patients received combined chemotherapy (CHT) with cisplatin and etoposide, and thoracic RT (TRT) was generally delivered sequentially following one to three cycles of CHT and consisted of either 56 Gy in 40 fractions for 4 weeks or 55 Gy in 22 fractions for 4–5 weeks. TRT fields encompassed primary tumor volume (post-CHT) and the involved nodal areas (pre- and post-CHT) without elective node irradiation. The local-regional failure was defined as failure within thoracic cavity and supraclavicular fossa except for pleural effusion, which was then divided into two subtypes: in-field and out-field failure according to the first occurred site in the planning target volume or not. Results: There were 89 patients completed the planed regimen and eligible for evaluating patterns of failure, 54 patients (57%) in 56 Gy cohort and 35 patients(43%) in 55 Gy cohort. The media cycles of CHT were 6 (4–8). The overall survival and local progression-free survival rates for 89 patients at 2 years were 56% and 71%, respectively, with a median survival of 25.6 months. 56 patients (63%) developed distant metastases and 21 patients (24%) developed local-regional failures: 12 in-field and 9 out-field. 8 out of 9 out-field failures occurred in the ipsilateral supraclavicular fossa, and the media duration to the end of TRT was 6 mouths (5–14). Comparing the 56 Gy and 55 Gy cohorts, the rates of any thoracic, in-field and out-field failures were no difference significantly. Conclusions: Thoracic radiotherapy using involved-field technique in patients with LSCLC resulted in a high failure rate of the supraclavicular fossa. Whether improving accuracy for the initial evaluation of clinical stage could reduce out-field failure in supraclavicular fossa need to be investigated.

No significant financial relationships to disclose.

The association between cigarette smoking and carotid intima-media thickness is influenced by the -930A/G CYBA gene polymorphism: the Cardiovascular Risk in Young Finns Study

BACKGROUND

Smoking-induced damage to the cardiovascular system has been shown in many studies; however, the degree of damage varies from individual to individual. We hypothesized that the -930A/G CYBA gene polymorphism in the NADPH oxidase influences the association between cigarette smoking and carotid intima-media thickness (IMT) in young healthy adults.

METHODS

Cross-sectional data obtained in 2001 for the Cardiovascular Risk in Young Finns Study were used. IMT was measured with ultrasound. The genotyping was performed using a 5'-nuclease assay. A linear regression model was used to test whether the interaction between smoking and the genotypes was associated with IMT. The magnitude of the interaction effect was further examined by performing a stratified analysis according to smoking habits.

RESULTS

In the entire population, the mean and maxima IMT were higher in smokers than nonsmokers (P = 0.005 and 0.008, respectively). The differences were most significant in subjects with the GG genotype, borderline significant for the GA genotype, and nonsignificant for the AA genotype. The interaction of genotypes with smoking was associated with mean and maximal IMT (P = 0.042 and 0.022). Among smokers, subjects with the GG genotype had a higher mean and maximal IMT compared with carriers of the A allele (P = 0.021 and 0.012). In contrast, the mean and maximal IMT were lower for G allele carriers than subjects with the AA genotype among nonsmokers (P = 0.022 and 0.026). All results had been adjusted for potential risk factors related to IMT.

CONCLUSION

The -930A/G polymorphism modifies the association between cigarette smoking and IMT in young healthy adults.

A 24-month subgroup analysis of the effect of denosumab on bone mineral density in women with breast cancer undergoing aromatase inhibitor therapy

Abstract #2106

Background: Accelerated bone loss and fracture risk are expected consequences of adjuvant aromatase inhibitor (AI) therapy. We previously showed that denosumab, a fully human monoclonal antibody that inhibits RANK ligand (RANKL), significantly increased bone mineral density (BMD) at the lumbar spine and at all measured skeletal sites at 12 months compared with placebo in women with breast cancer undergoing adjuvant AI therapy (Ellis et al, 2007 SABCS). In this analysis, we assessed covariates that may influence treatment effects on BMD at the lumbar spine, total hip, femoral neck, and 1/3 radius at 24 months.
 Methods: Adult patients (pts) with hormone receptor-positive breast cancer, who had evidence of low bone mass and were receiving adjuvant AI therapy, were enrolled in this randomized, double-blind, placebo-controlled, phase 3 study. Pts were stratified according to length of previous AI therapy (≤ 6 vs > 6 months) and randomly assigned to receive, together with calcium and vitamin D, placebo (n=125) or denosumab 60 mg (n=127) subcutaneously every 6 months for 4 doses. Subgroup analysis was conducted using analysis of covariance and adjusted for treatment, stratification factor, baseline BMD value, densitometer type, and baseline BMD value-by-densitometer-type interaction.
 Results: At 24 months, greater increases in BMD were seen at all measured skeletal sites (both trabecular and cortical bone) for denosumab compared with placebo, regardless of the subgroup (table). Adverse events (AEs) occurred at a similar rate in both groups (91% denosumab, 90% placebo).
 Conclusion: In pts with breast cancer undergoing adjuvant AI therapy, twice-yearly denosumab treatment showed consistent increases in BMD across the skeleton at 24 months compared with placebo, regardless of subgroups.
 


Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2106.

Notch1 induces cell cycle arrest and apoptosis in human cervical cancer cells: involvement of nuclear factor kappa B inhibition

Notch signaling can serve as a tumor suppressor or tumor promoter in the same kind of cancer, such as human papillomavirus-positive cervical cancer cells. However, the exact mechanisms remain poorly characterized. Our studies demonstrated that constitutively overexpressed active Notch1 via stable transfection with exogenous intracellular domain of Notch1 (ICN) resulted in growth inhibition of the human cervical cancer cell line HeLa by inducing G(2)-M arrest and apoptosis. Moreover, the growth inhibition was correlated with inhibition of nuclear factor kappa B (NF-kappaB) p50 activation, accompanied by a decrease in the nuclear expression of NF-kappaB p50 and an increase in the cytosolic expression of IkappaBalpha. Consistent with these results, downregulation of cyclin D1 and Bcl-2, which are both the downstream genes of NF-kappaB, were observed in ICN-overexpressed cells. Overall, our results suggest that NF-kappaB inhibition may contribute partially to cell cycle arrest and apoptosis induced by Notch1 activation in human cervical cancer cells.

Randomized, active-controlled study of denosumab (AMG 162) in breast cancer patients with bone metastases not previously treated with intravenous (IV) bisphosphonates (BP)

512

Background: Receptor activator of NF-κB ligand (RANKL) is a key mediator of osteoclast formation, function, and survival. Denosumab, a fully human monoclonal antibody, binds and inhibits RANKL, thus suppressing excess osteoclastic activity associated with bone metastases. We report interim efficacy and safety results of an ongoing, phase 2 study of denosumab in IV BP treatment-naïve women with advanced breast cancer and bone metastases (BM). Methods: Eligible patients (pts; age ≥ 18 yrs with breast cancer; confirmed BM; naive to IV BP therapy) were stratified by chemo- or hormonal therapy and randomized to 1 of 6 cohorts (5 denosumab [double blind]; 1 IV BP [open label]; see table ). The primary endpoint was the % change from baseline (BL) to week 13 in the resorption marker, urinary N-telopeptide (uNTx), corrected for creatinine. Also evaluated were % of pts with ≥ 65% decrease in uNTX from BL, time to a 65% reduction in uNTx, % of pts with ≥ 1 skeletal-related event (SRE), and safety. Results: In total, 255 pts (∼40/cohort) were enrolled. Mean age was 57 to 59 yrs (denosumab cohorts) vs 52 yrs (BP). Most pts had > 2 sites of BM (denosumab, 74%; BP, 81%); 51% and 49% received concurrent chemo- or hormonal therapy, respectively. As shown in the efficacy table , the 120 mg Q4W dose resulted in the greatest % decrease from BL in uNTx. At data cutoff, the % of all denosumab pts with ≥ 1 SRE was 9% (20/212) vs 16% (7/43) of BP pts. Commonly reported adverse events (AE) among all pts included nausea, vomiting, asthenia, diarrhea, and bone pain. Of 198 denosumab pts tested, none developed anti-denosumab antibodies. Conclusion: In this interim analysis, denosumab resulted in rapid and sustained suppression of bone turnover and was at least as effective as IV BP at reducing the risk of SREs, with a safety profile similar to that seen in advanced breast cancer pts receiving cancer treatment.

[Table: see text]

[Table: see text]

A randomized trial of denosumab (AMG 162) versus intravenous (IV) bisphosphonates (BP) in cancer patients (pts) with bone metastases (BM) on established IV BP and evidence of elevated bone resorption

8562

Background: Pts on established (≥ 8 weeks) IV BP who have elevated bone resorption markers, especially urinary N-telopeptide (uNTx), are at increased risk for skeletal related events (Coleman, J Clin Oncol 2005). Denosumab, a fully human monoclonal antibody, inhibits osteoclastic bone resorption by binding and neutralizing RANK ligand, a key mediator of osteoclast differentiation and function. Denosumab efficacy and safety were evaluated in a phase 2, randomized, open label, active-controlled study in advanced cancer pts with BM and elevated levels of uNTX despite established IV BP therapy. We report preliminary results from an interim analysis of 49 pts at week 13. Methods: Eligible pts (≥18 yrs old with solid tumor [except lung] or multiple myeloma [MM]; confirmed BM; screening uNTx > 50 nM BCE/mM creatinine [Cr]; on IV BP for ≥ 8 weeks before randomization) are stratified by baseline uNTx (50–100, >100) and tumor type. Pts are randomized to 1 of 3 arms: IV BP every 4 weeks (Q4W) or 180 mg denosumab given subcutaneously Q4W or Q12W. The primary endpoint is the proportion (%) of pts with uNTx < 50 nM BCE/mM Cr at week 13. Enrollment is ongoing (planned N = 135). Results: The mean (range) age of all pts in the analysis (33 denosumab; 16 BP) was 62.5 (39, 81) yrs; 96% had > 2 BM. The median time on prior IV BP (mostly zoledronic acid) was 5.1 months. Tumors included prostate (n = 24), breast (n = 20), other/MM (n = 5). The % of pts with uNTx < 50 nM BCE/mM Cr at week 13 was greater with denosumab (pooled arms) than IV BP: 76% (95% CI: 60.3, 91.2) vs 38% (95% CI: 18.5, 61.4; P = .015 Cochran-Mantel-Haenzel), respectively. No treatment-related serious adverse events (SAEs) were reported. Commonly reported AEs in the denosumab arms included nausea, peripheral edema, anemia, bone pain, and constipation. At data cutoff, 10 deaths (6/33 denosumab, 4/16 BP) had occurred on-study. Conclusions: These interim data suggest that denosumab normalizes uNTx more frequently than IV BP in pts with elevated uNTx despite 8 weeks of IV BP, across all tumor types. The AE profile of denosumab appeared similar to that of cancer pts undergoing treatment.

[Table: see text]

Adsorption of arsenic(V) by activated carbon prepared from oat hulls

The efficiency of self-manufactured activated carbon (AC) produced from oat hulls in adsorbing arsenic(V) was tested in a batch reactor. The results indicated that the adsorptive capacity of AC was affected by initial pH value, with adsorption capacity decreasing from 3.09 to 1.57 mg As g(-1) AC when the initial pH values increased from 5 to 8. A modified linear driving force model conjugated with a Langmuir isotherm was created to describe the study's kinetics. The test results show that rapid adsorption and slow adsorption exist simultaneously when AC is used to remove arsenic(V).

Molecular monitoring and evaluation of the application of the insect-pathogenic fungus Beauveria bassiana in southeast China

AIMS

To monitor the fate of inundatively applied strains of Beauveria bassiana against Masson's pine caterpillar, Dendrolimus punctatus, in Magushan Forest, southeast China, and evaluate the potential environmental risks of biocontrol introduction.

METHODS AND RESULTS

Filed samplings of mycosed cadavers were carried out continuously for more than one year after the inundative applications of two exotic B. bassiana strains. By employing four complementary molecular markers, the purified cultures from collections were characterized and the two released strains Bb17 and Bb13 were recovered with respective frequencies of 9.1 and 5.2%. The released strains were isolated from nontarget hosts. The genetic diversity of the population of B. bassiana in the trial plot changed dynamically over time and no single genotype strain dominated throughout the sampling period or at different seasons. The indigenous strains were observed to be predominant in the local environment. Co-infection and/or genetic recombination might occur between strains under natural conditions.

CONCLUSION

Field applications of the biocontrol agent B. bassiana appear to pose no major risk to the environment. There was no evidence of displacement of indigenous strains of B. bassiana.

SIGNIFICANCE AND IMPACT OF THE STUDY

The results indicate that the introduction of exotic B. bassiana strains can persist in local environment and infect nontarget insect hosts, highlighting the importance of safety assessment of the large-scale application of fungal biocontrol agents.

Steam activation of chars produced from oat hulls and corn stover

Oat hulls and corn stover were used to produce chars at approximately 500 degrees C. The carbon concentrations of oat hull char and corn stover chars produced were 72.3 and 68.0 wt.%, respectively. Both activation burn-off and Brunauer-Emmett-Teller (BET) surface area appear to exhibit a linear relationship with respect to activation time of oat hulls. As to corn stover activated carbons, there is no linear relationship between activation time and BET surface area. However, activation burn-off of and activation time appear to relate in a linear manner for the activated carbons produced from corn stover chars. Oat hull is better than corn stover as a raw material for the production of activated carbon.

Radiation-induced pulmonary toxicity: a dose-volume histogram analysis in 201 patients with lung cancer

PURPOSE

To relate lung dose-volume histogram-based factors to symptomatic radiation pneumonitis (RP) in patients with lung cancer undergoing 3-dimensional (3D) radiotherapy planning.

METHODS AND MATERIALS

Between 1991 and 1999, 318 patients with lung cancer received external beam radiotherapy (RT) with 3D planning tools at Duke University Medical Center. One hundred seventeen patients were not evaluated for RP because of <6 months of follow-up, development of progressive intrathoracic disease making scoring of pulmonary symptoms difficult, or unretrievable 3D dosimetry data. Thus, 201 patients were analyzed for RP. Univariate and multivariate analyses were performed to test the association between RP and dosimetric factors (i.e., mean lung dose, volume of lung receiving >or=30 Gy, and normal tissue complication probability derived from the Lyman and Kutcher models) and clinical factors, including tobacco use, age, sex, chemotherapy exposure, tumor site, pre-RT forced expiratory volume in 1 s, weight loss, and performance status.

RESULTS

Thirty-nine patients (19%) developed RP. In the univariate analysis, all dosimetric factors (i.e., mean lung dose, volume of lung receiving >or=30 Gy, and normal tissue complication probability) were associated with RP (p range 0.006-0.003). Of the clinical factors, ongoing tobacco use at the time of referral for RT was associated with fewer cases of RP (p = 0.05). These factors were also independently associated with RP according to the multivariate analysis (p = 0.001). Models predictive for RP based on dosimetric factors only, or on a combination with the influence of tobacco use, had a concordance of 64% and 68%, respectively.

CONCLUSIONS

Dosimetric factors were the best predictors of symptomatic RP after external beam RT for lung cancer. Multivariate models that also include clinical variables were slightly more predictive.

Analysis of gene expression following sciatic nerve crush and spinal cord hemisection in the mouse by microarray expression profiling

1. The responses of periphery (PNS) and central nervous systems (CNS) towards nerve injury are different: while injured mammalian periphery nerons can successfully undergo regeneration, axons in the central nervous system are usually not able to regenerate. 2. In the present study, the genes which were differentially expressed in the PNS and CNS following nerve injury were identified and compared by microarray profiling techniques. 3. Sciatic nerve crush and hemisection of the spinal cord of adult mice were used as the models for nerve injury in PNS and CNS respectivey. 4. It was found that of all the genes examined, 14% (80/588) showed changes in expression following either PNS or CNS injury, and only 3% (18/588) showed changes in both types of injuries. 5. Among all the differentially expressed genes, only 8% (6/80) exhibited similar changes in gene expression (either up- or down-regulation) following injury in both PNS and CNS nerve injuries. 6. Our results indicated that microarray expression profiling is an efficient and useful method to identify genes that are involved in the regeneration process following nerve injuries, and several genes which are differentially expressed in the PNS and/or CNS following nerve injuries were identified in the present study.