Analysis of DNA methylation patterns and levels in maize hybrids and their parents

Heterosis is the superior performance of heterozygous individuals and has been widely exploited in plant breeding, although the underlying regulatory mechanisms still remain largely elusive. To understand the molecular basis of heterosis in maize, in this study, roots and leaves at the seedling stage and embryos and endosperm tissues 15 days after fertilization of 2 elite hybrids and their parental lines were used to estimate the levels and patterns of cytosine methylation by the methylation-sensitive amplification polymorphism method. The relative total methylation levels were lower in all the tissues of all hybrids than their corresponding mid-parent values, and the number of demethylation events was higher in the hybrids. These results implied that the decreasing trend and demethylation in hybrids relative to their parents may enable the derepression and possibly expression of many genes that were associated with the phenotypic variation in hybrids. To further analyze the observed methylation pattern changes, a total of 63 differentially displayed DNA fragments were successfully sequenced. Basic Local Alignment Search Tool analysis showed that 11 fragments shared similarity with known functional proteins in maize or other plant species, including metabolism, transposon/retrotransposon, development, stress response, and signal transduction, which indicated that these genes might play a significant role in maize hybrid vigor.

Analysis of DNA methylation patterns and levels in maize hybrids and their parents

Heterosis is the superior performance of heterozygous individuals and has been widely exploited in plant breeding, although the underlying regulatory mechanisms still remain largely elusive. To understand the molecular basis of heterosis in maize, in this study, roots and leaves at the seedling stage and embryos and endosperm tissues 15 days after fertilization of 2 elite hybrids and their parental lines were used to estimate the levels and patterns of cytosine methylation by the methylation-sensitive amplification polymorphism method. The relative total methylation levels were lower in all the tissues of all hybrids than their corresponding mid-parent values, and the number of demethylation events was higher in the hybrids. These results implied that the decreasing trend and demethylation in hybrids relative to their parents may enable the derepression and possibly expression of many genes that were associated with the phenotypic variation in hybrids. To further analyze the observed methylation pattern changes, a total of 63 differentially displayed DNA fragments were successfully sequenced. Basic Local Alignment Search Tool analysis showed that 11 fragments shared similarity with known functional proteins in maize or other plant species, including metabolism, transposon/retrotransposon, development, stress response, and signal transduction, which indicated that these genes might play a significant role in maize hybrid vigor.

Barriers to tuberculosis care for drug users in two provinces of China: a qualitative study

SETTING

Two compulsory drug rehabilitation centres in Yunnan and Sichuan Provinces, Southwest China.

OBJECTIVE

To understand barriers to tuberculosis (TB) care among drug users in China, and to provide policy recommendations to improve TB control in the drug-using population.

DESIGN

A qualitative study was designed using in-depth interviews with 147 drug users with TB and 12 key informants. Drug users were purposively selected from two compulsory drug rehabilitation centres and key informants from national and provincial justice administration, local TB control dispensaries and compulsory drug rehabilitation centres.

RESULTS

Lack of health awareness and knowledge was reported as one barrier to TB care among drug users. The majority of the respondents lacked social support and perceived fear and stigma when seeking TB care. More than half of the respondents who had discontinued their anti-tuberculosis treatment reported that this was due to drug use. Limited provision of TB care in the compulsory drug rehabilitation centres and local TB control dispensaries was also reported as one of the barriers to TB care among drug users.

CONCLUSIONS

These findings suggest that barriers to TB care for drug users are associated not only with the drug users themselves, but also with the providers and societal factors. Health professionals and policy makers should be aware of these barriers in China.

Sequential one-pot enzymatic synthesis of oligo-N-acetyllactosamine and its multi-sialylated extensions

A simple and efficient protocol for the preparative-scale synthesis of various lengths of oligo-N-acetyllactosamine (oligo-LacNAc) and its multi-sialylated extensions.

Abstract P4-01-07: Evaluation of FLT PET-CT as an imaging biomarker of proliferation in primary breast cancer

Background

[18F]flurothymidine (FLT) is proposed as an positron emission tomography (PET) imaging biomarker of proliferation for breast cancer. The aim of this prospective study was to assess the feasibility of FLT PET-CT as a technique for predicting response to neoadjuvant chemotherapy (NAC) in operable breast cancer and to compare baseline FLT to Ki-67.

Methods

20 patients with primary breast cancer were recruited into this study and 19 received NAC with FEC (n = 6) or FEC-T (n = 13). A baseline FLT PET-CT scan was performed and repeated before the second cycle of chemotherapy. Expression of Ki-67 in the diagnostic biopsy was quantified after being stained by Dako Ki67 MIB-1 antibody and% positive cells scored. From the FLT PET-CT scans standardized uptake value maximum (SUVmax) were calculated.

Results

All 20 patients completed the baseline scan and 17 completed the second scan. Baseline Ki-67 results were available for 19 patients. Median age was 52 years (range 32 to 67), 12 patients were ER/ PR +ve, 6 Her-2 +ve and 6 triple negative.

Mean baseline SUVmax was 7.3 (range 2.92 to 13.87) and 4.62 (range 1.79 to 14.15) post 1 cycle of NAC (range 7 to 14 days), representing a drop of 2.68 (36.3%). Mean baseline Ki-67 was 32.23 (range 2.3 to 68.4). Pearsons correlation showed a significant correlation between pre-chemotherapy Ki-67 and SUVmax of 0.604 (p = 0.006).

7 out of 17 (41%) patients achieved near pCR or pCR (pathological responders) after NAC and all of these had a reduction in SUVmax with a mean percentage value of –36.5% (range -0.5% to -62.5%). 10 out of 17 (59%) patients were non-responders and 8 of these had a reduction in SUVmax with a mean percentage value of -36.2% (range 11.3% to -70.7).

Conclusions

Baseline SUVmax measurements of FLT PET-CT were significantly related to Ki-67 suggesting that it is a proliferation biomarker. However, in this series neither the baseline value or the change in SUVmax after one cycle of NAC were able to predict response as most patients had a sizeable SUVmax reduction.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-01-07.

Routine and dynamic MR imaging study of lobular capillary hemangioma of the nasal cavity with comparison to inverting papilloma

BACKGROUND AND PURPOSE

Lobular capillary hemangioma is an uncommon lesion, and its MR imaging appearance has not been fully characterized. The purpose of this study was to determine the MR imaging features of nasal lobular capillary hemangioma and contrast its imaging characteristics to inverting papilloma.

MATERIALS AND METHODS

The MR imaging signals of 32 patients with histopathologically proven nasal lobular capillary hemangiomas and 53 patients with nasal inverted papillomas were retrospectively studied. The findings of dynamic contrast-enhanced MR imaging in 24 lobular capillary hemangiomas and in 53 inverted papillomas were also analyzed. The Monte Carlo exact test was used for comparison of the time-intensity curve patterns of lobular capillary hemangioma and inverted papilloma.

RESULTS

All lobular capillary hemangiomas appeared to be homogeneously isointense to gray matter on T1-weighted images. On T2-weighted images, all lesions showed heterogeneous hyperintensity, and a thin peripheral isointense or hypointense ring was seen in 28 patients. All lesions showed marked enhancement on enhanced images, with the exception of enhancement of the T2 isointense or hypointense ring. Forty-three (81.1%) inverted papillomas had moderate heterogeneous T2 signal intensity, and a characteristic "cerebriform" appearance was detected in 45 (84.91%) of 53 inverted papillomas. The time-intensity curves showed a washout pattern in 18 and a plateau pattern in 6 patients, whereas inverted papillomas showed a washout pattern in 12, a plateau pattern in 35, and a persistent pattern in 6 patients. There was a statistically significant difference as to time-intensity curve pattern between the 2 groups (P < .05).

CONCLUSIONS

Hyperintensity on T2-weighted images, marked enhancement of tumor with a nonenhancing thin peripheral ring, and a washout time-intensity curve pattern are characteristic MR imaging features of nasal lobular capillary hemangiomas.

Complementary laboratory indices for predicting the disease status of patients with hepatitis B virus infection

To identify complementary laboratory indices for determining the disease status of patients with hepatitis B virus. Subjects were divided into six groups: hepatitis B virus carrier, mild chronic hepatitis B, moderate chronic hepatitis B, severe chronic hepatitis B, fulminant hepatitis B and healthy controls. Serum alanine aminotransferase, total bilirubin and direct bilirubin were measured by an automatic analyser. The levels of T-cell immunoglobulin domain and mucin-domain-containing molecule-3, macrophage inflammatory protein 2, neutrophil gelatinase-associated lipocalin and inducible nitric oxide synthase were measured by ELISA. T-cell immunoglobulin domain, mucin-domain-containing molecule-3, macrophage inflammatory protein 2 and inducible nitric oxide synthase levels were significantly higher in patients with severe chronic hepatitis B compared with those in patients with mild and moderate chronic hepatitis B or fulminant hepatitis B (P < 0.05). When normal or abnormal alanine aminotransferase was present, significant differences between macrophage inflammatory protein 2 and T-cell immunoglobulin domain and mucin-domain-containing molecule-3 levels between patients with mild, moderate, severe chronic hepatitis B or fulminant hepatitis B were observed (P < 0.05). Our results suggest that T-cell immunoglobulin domain and mucin-domain-containing molecule-3 and macrophage inflammatory protein 2 could serve as alanine aminotransferase, direct bilirubin or total bilirubin complementary indices for determining the status of patients with hepatitis B.

Degradation of nitenpyram pesticide in aqueous solution by low-temperature plasma

In order to study the new technique of plasma wastewater treatment, the degradation behaviour ofnitenpyram (NTP) pesticide was investigated in a low-temperature plasma formed during a dielectric barrier discharge process. The reactor was a radial flow sedimentation tank centred around the water inlet. We studied the effect of pesticide concentration and input power of the dielectric barrier discharge, together with the effect of external factors on the degradation of nitenpyram pesticide wastewater such as conductivity and the use of various of catalysts, and the reaction products were analyzed by high-performance liquid chromatography mass spectrometry (HPLC-MS). The results showed that NTP could be effectively removed from aqueous solution by low-temperature plasma. Increasing the input power could improve the efficiency of degradation, conforming to a first-order kinetic model. Use of a suitable catalyst clearly improved the degradation process, as also did low conductivity. The pH of NTP was reduced with discharge time.

Abstract P1-06-01: Upregulation of metabolism as a potential resistance mechanism to bevacizumab in primary breast cancer

Background: Recently the FDA has withdrawn the indication for bevacizumab in metastatic breast cancer after several clinical studies failed to demonstrate an overall survival benefit. These studies however did report an increase in response rates to chemotherapy and improvement in progression free survival, suggesting a pattern of response to the drug followed by the development of resistance. We have little knowledge of the molecular mechanisms driving the development of resistance to bevacizumab. To better understand these mechanisms, we have conducted a window of opportunity study using a single cycle of bevacizumab with detailed pharmacodynamic assessments using gene expression arrays and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI).

Methods: After ethical approval, 47 newly diagnosed locally advanced breast cancer patients were prospectively enrolled in this trial. Patients received single dose bevacizumab (15mg/ kg) 2 weeks prior to neoadjuvant chemotherapy and underwent core biopsies for gene expression and immunohistochemistry analysis and DCE-MRI scans before and 2 weeks after bevacizumab. 35 patients who had invasive ductal carcinoma together with good quality MRI scans and core biopsies before and after bevacizumab were included in this analysis. Pharmacokinetic (PK) modelling techniques were used to quantify PK parameters (Ktrans, kep, ve) from the DCE-MRI data. Gene expression profiling was performed using the Affymetrix Human Exon 1.0 ST arrays.

Results: The majority of patients (28/35) showed a significant reduction in vessel permeability and blood flow of at least 30% following bevacizumab, with a mean decrease in the forward transfer constant (P &lt; 0.0001) and the reverse rate constant kep (P &lt; 0.0001). From gene expression and immunohistochemistry analyses, we identified several key metabolism-related genes that are significantly up-regulated after bevacizumab treatment, including pyruvate dehydrogenase kinase isozyme 1 (PDK1) (fig.1) and carbonic anhydrase 9 (CA9). In addition, we found a number of interesting genes that are down-regulated after bevacizumab treatment, including sulfatase-1 (SULF1), and cyclin E1 (CCNE1).

Discussion: This study highlights that the combination of DCE-MRI and gene expression arrays can lead to an improved understanding of the molecular mechanisms governing response and resistance to anti-angiogenic therapy. Heterogeneity of response to bevacizumab was demonstrated, with some tumours showing increases or no change in Ktrans and others marked reductions, which may be of value in early stratification for therapy maintenance. Furthermore, the gene expression analysis showed activation of pathways, which could contribute to the development of resistance. For example, we observed significant up regulation of genes involved in regulating the switch from mitochondrial metabolism to glycolysis, such as PDK1. This suggests that using bevacizumab with the other targeted agents such as Dichloroacetate, a PDK1 inhibitor might be helpful in overcoming the development of resistance and ultimately lead to improved patient survival. Our preclinical studies strongly support this possibility.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P1-06-01.

Raising Harmonic Variation of Arterial Pulse in Dying Rats

Our previous study revealed that the coefficient of variation of harmonic magnitude (HCV) of radial arterial pulse was significantly raised before the death of cancer patients. In this study, we recorded the caudate arterial pulse of 24 Sprague-Dawley rats that had a fatal dose of urethane injected into their abdomens. Twenty rats were dead within 3 hours after the injection and four survived. We defined the last 100 minutes of each rat's life as the dying process. During the dying process, we found that both the systolic blood pressure and diastolic blood pressure dropped steeply during the last 5 minutes. However, all HCVs, except HCV1, climbed steeply before the last 5 minutes. The HCV1 of the dying rats was significantly higher than that of rats that survived, starting from the first minute (P<0.01). The HCV2 of the dying rats was significantly higher than that of the survived rats starting from the 52nd minute (P<0.05). The HCV3 and HCV4 of the dying rats were significantly higher than those of the survived rats until the 70th minute and the 80th minute, respectively (P<0.05). Furthermore, HCV2–HCV4 proceeded with the dying process and increased gradually. We concluded that HCVs, which failed first in the high-frequency components and then in the low-frequency components, could provide physicians with earlier information to prevent the coming failure of circulatory system, and could reflect quantitatively pathological severity and predict patient outcome. The specific Fourier components in the pulse provide more physiological information than systolic and diastolic blood pressures.

P3-14-12: Local Control of Primary Breast Cancer Treated with Radical Radiotherapy Alone after Neoadjuvant Chemotherapy

Introduction: The aim of this retrospective study was to evaluate the local recurrence rates in a cohort of patients who achieved a complete clinical response (cCR) to neoadjuvant chemotherapy and did not have surgery.

Materials and Methods: 148 women who achieved a cCR to neoadjuvant chemotherapy were identified from a prospectively maintained database (1995-2011) of 667 patients. 122 patients went on to have surgery (either wide local excision or mastectomy) followed by radiotherapy. In 26 patients (median age 49, range 35–72 years; T2-T4, N0-N3, M0), no surgery was performed but all received radical radiotherapy. Surgery was avoided due to either physician or patient choice. Recurrence was defined as first relapse of disease, either local (ipsilateral breast and/or axilla) or distant.

Results: All 26 patients who avoided surgery had neoadjuvant chemotherapy with 20 patients (77%) receiving anthracycline-based (FEC, FAC, ECF), 5 (19%) MMM and 1 (4%) CMF chemotherapy. The median number of cycles was 6 (range 4–8). Chemotherapy was followed by radical external beam radiotherapy to the breast +/− supraclavicular fossa and axilla (median dose delivered, 60Gy in 2Gy fractions). All were identified as operable at diagnosis including 3 patients who had supraclavicular lymphadenopathy. All 26 patients achieved a final cCR in the breast to chemotherapy. 21 patients had imaging with mammography and/or ultrasonography to assess radiological response at the end of neoadjuvant chemotherapy, of which 19 had a complete response and 2, a partial response. After a median follow-up of 144 months, 10/26 (38%) patients experienced local disease recurrence (2 also had distant recurrence) and 4/26 (15%) patients with distant metastases only. Patients with local recurrence only, went on to have a mastectomy whilst those with distant disease received systemic therapy. There were 10 deaths, 9 of which were breast cancer related (33%).

Conclusions: Local recurrence rates were high in patients achieving a cCR following neoadjuvant chemotherapy and who avoided surgery. Our practice has subsequently changed to include clip insertion and surgical excision on completion of chemotherapy. With increasing pathologic complete response rates to more active chemotherapy schedules (including taxanes +/− herceptin), it is being proposed that surgery could be avoided in selected patients. Our study shows that caution should be exercised.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-14-12.

Abstract PD07-04: Predicting Outcome with Ki67 in Primary Breast Cancer in the Neoadjuvant Setting

Background: The proliferation antigen Ki67 has been shown to be a reliable predictive marker of treatment efficacy in the neoadjuvant treatment of breast cancer but its prognostic significance remains uncertain. This study assesses Ki67 before and after neoadjuvant chemotherapy (NAC) in relation to long-term outcome. Methods: 117 patients with primary breast cancer due to undergo NAC were studied (median age 48 years, range 25-78; T2-4, N0-3, M0) and information gathered from a prospectively maintained database. Immunohistochemically derived Ki67 expression was obtained from pretreatment core biopsy and surgical specimens. Their relationship to DFS and OS was analyzed along with known prognostic variables (age, ER/PR/HER2 status, clinical and pathologic T and N stage, grade), NAC regimen, response and adjuvant treatment. Survival curves were estimated using the Kaplan-Meier method and a log-rank test used to determine significance using a two-tailed p-value of 0.05. A multivariate Cox proportional hazards regression model performed in a stepwise fashion was used to determine the prognostic value of each signifcant variable. Results: 84 patients with matched biopsy and surgical samples were assessable for pre and post NAC Ki67 levels. The majority (90%) received anthracycline based NAC (median number of cycles 6, range 2-6). On univariate analysis, the only significant pretreatment predictive factor for shorter DFS was higher clinical nodal stage (cN) (P&lt;0.001). Posttreatment variables that predicted for worse DFS were: Ki67 at surgery (HR 1.52, p=0.048), pathologic nodal stage (pN) (p=0.001) and grade (p=0.013). On multivariate analysis, pN was the most powerful predictor for DFS (chi-squared test 19.8, 3 df, P&lt;0.001). Univariate analysis of pretherapy factors for OS revealed that Ki67 at biopsy (HR 2.06, p=0.039), cN (HR 4.44, P&lt;0.001) and PR positivity (HR 0.41, p=0.012) were significant. Significant posttreatment variables for OS were Ki67 at surgery (HR 2.01, p=0.006), pN (p=0.001), and grade (p=0.009). PR status and pN remained important predictors of OS on multivariate analyses. Conclusions: The expression of Ki67 is a widely accepted marker of cellular proliferation in breast cancer. Ki67 levels after NAC were a better predictor for long-term outcome than pretherapy Ki67, although nodal status appears to be the most powerful determinant overall. High Ki67 levels post NAC may identify patients with poorer outcomes who are candidates for further systemic therapy.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr PD07-04.

Abstract P2-02-07: Predicting Response to Bevacizumab Therapy in Primary Breast Cancer Using Dynamic Contrast-Enhanced Magnetic Resonance Imaging

Background: Anti-angiogenic therapy holds much promise for the treatment of breast cancer. In practice however, only a subset of patients who receive these drugs demonstrate a significant response to therapy. A key challenge therefore is to elucidate markers that are predictive of response to anti-angiogenic agents such as bevacizumab, and which would enable the selection of patients who would get the most benefit from these expensive therapies.

Materials and Methods: We used high temporal resolution dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to assess tumor vascularity in 20 patients with primary breast cancer. Patients were imaged both before and two weeks after single dose Bevacizumab therapy (15mg/kg). Pharmacokinetic modelling techniques were used to quantify the volume transfer constant Ktrans, the rate constant kep, and the fractional volume of the extra-vascular extracellular space ve. Specifically, we used Tofts model with a population-based arterial input function (modified Fritz-Hansen) to model the contrast agent concentration time courses on a voxel-wise basis. Non-enhancing voxels were detected automatically with the use of a Bayesian noise model, and the corresponding pharmacokinetic parameter values for these voxels were set to zero. The median pharmacokinetic parameter values over the tumor volumes of interest were then computed both pre-and post Bevacizumab. Results: We found marked variation across patients in the baseline level and percentage change in median Ktrans, kep and ve following Bevacizumab. In particular, median Ktrans at baseline ranged form 0.12 to 0.88. Changes in median Ktrans varied from −97% to +19% across all patients, with an average change of −49%. Notably, we found a highly significant negative correlation (r = −0.92, P = 1e-08) between the absolute change in median Ktrans and the median Ktrans at baseline. In particular, tumors with a high median Ktrans at baseline demonstrated the greatest change in Ktrans following Bevacizumab therapy, whereas tumors with low median Ktrans at baseline demonstrated relatively little change in Ktrans. Discussion: Although Ktrans is a complex function of vessel permeability, surface area, and tumor blood flow, it has previously been demonstrated to be a reliable biomarker of response to anti-angiogenic therapy in a number of different cancers. Our results illustrate that therapy-induced changes in Ktrans can be predicted from the value of Ktrans at baseline, and hence DCE-MRI scans may enable the selection of primary breast cancer patients who show the greatest response to single-dose Bevacizumab therapy. Whether this will translate into longer term benefit and improvements in outcome for patients remains to be shown. The relationship between baseline and pre-/post-therapy change in Ktrans with the corresponding changes in gene expression is currently under study in a larger number of patients. Figure available in online version.

Abstract P4-03-03: Lower Vitamin D Levels Are Highly Prevalent in Women with Breast Cancer

Purpose: The objectives of this study were to determine the prevalence of vitamin D insufficiency or deficiency as measured by serum 25-hydroxyvitamin D (25-OHD) in women with breast cancer and relate this to age, ethnic group, disease stage, and seasonal variation. Methods: Levels of serum 25-OHD were requested on blood samples collected from 129 female patients with histologically-proven breast cancer (median age 61 years; range, 30-88). Vitamin D deficiency was defined as serum 25-OHD less than 12.5 nmol/L, insufficiency as 12.5 to 50 nmol/L, and sufficient levels as greater than 50 nmol/L. The prevalence of inadequate (insufficient or deficient) vitamin D levels and median 25-OHD values were calculated for the cohort as a whole and analysed according to age, ethnicity (Asian (Indian/Pakistani), White and other), disease stage (early versus metastatic), and seasons. Statistical analysis was performed using non-parametric methods and a significance level set at a two-tailed p-value &lt; 0.05.

Results: Overall 52% of women had inadequate levels of 25-OHD (45% deficient, 7% insufficient; median 29 nmol/L). There was no relationship with age. Lower levels were more common in Asian women (n=56) (64%; 16% deficient, 48% insufficient) compared with white women (n=65) (40%; all insufficient) and other (n=8) (62.5%; all insufficient). 25-OHD levels were significantly lower overall in Asian women in comparison with white women (median 36.5 versus 60 nmol/L; p=0.0002). When disease stage was considered, 54% of women with early breast cancer had inadequate 25-OHD levels (n=103) (7% deficient, 47% insufficient) in comparison with 42% of women with metastatic disease (n=26) (8% deficient, 34% insufficient) although overall levels were not significantly different between groups. There was no seasonal variation in 25-OHD levels.

Conclusion: The prevalence of insufficient or deficient vitamin D levels as assessed by 25-OHD in women with breast cancer, especially in the Asian population, is high. Our findings suggest that all patients with breast cancer should have routine testing of vitamin D status and if appropriate, offered adequate vitamin D supplementation.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P4-03-03.

Abstract P2-09-28: Integrated Gene Expression and MRI Analysis To Assess Early Therapeutic Response to Bevacizumab in Primary Breast Cancer

Background: Bevacizumab is an approved drug for advanced breast cancer alongside chemotherapy. To date there is no biomarker proven to be effective in patient stratification. To address this, a window of opportunity study was designed where bevacizumab is administered as a short-term first line treatment with a detailed pharmacodynamic assessment to identify the patients who are most likely to benefit from this therapy. This assessment consisted of Dynamic Contrast-Enhanced Magnetic Resonance Imaging (DCE-MRI) and gene expression analysis.

Method: This is an on going two-centre, Phase II, non-randomised study. 43 locally advanced breast cancer patients aged &gt;18 years, with performance status 0-1 who have adequate bone marrow, renal and liver functions have been enrolled. A single infusion of bevacizumab (15mg/kg) was given prior to commencement of neoadjuvant chemotherapy. DCE-MRI and core biopsies for exon gene array analysis were performed both at baseline and 2 weeks after bevacizumab. Pharmacokinetic modelling of DCE-MRI was used to quantify the volume transfer constant Ktrans, the rate constant kep, and the fractional volume of the extra-vascular extracellular space ve. The median pharmacokinetic parameter values over the tumour volumes of interest were then computed both pre-and post-bevacizumab.

Results: Our initial gene expression analysis from 21 patients showed a high variability in the response. This was true for both single gene analysis and pathway signatures. In particular the expression fold changes of hypoxia and proliferation signatures after bevacizumab ranged from a minimum of 0.6 fold decrease to a maximum of 4.3 fold increase. Interestingly, fold changes in both these signatures were significantly positively correlated (Spearman rho=0.81, P&lt;0.001). Changes in the proliferation signature were significantly inversely correlated with changes in mean and median ve (rho=-0.57, P&lt;0.01 in both cases). Changes in the hypoxia signature were significantly inversely correlated with changes in mean and median kep (rho=-0.48, p=0.03 and rho=-0.58, p=0.007 respectively). Significantly over-represented pathways amongst genes up-regulated after bevacizumab were T-cell activation, inflammation, PDGF and apoptosis signalling. Discussion: Our initial results provide several potentially important avenues for further research, which may be useful in the identification of new therapeutic approaches. For example, the unexpected correlation of induction of hypoxia and proliferation in the same tumours has important implications for combination therapy. Furthermore, patients whose tumours showed the largest reduction in kep, a measure of vascular leakiness, also showed the greatest increase in hypoxia. In addition, patients who experienced the largest reduction in ve showed the highest fold change in proliferation. Although these results are preliminary and will need to be confirmed at study completion, they illustrate how the integrated analysis of DCE-MRI pharmacokinetic parameters and the corresponding gene expression profiles may enable an improved understanding of the mechanisms governing response and resistance to bevacizumab.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P2-09-28.

Rapid method for simultaneous determination of flavonoid, saponins and polyacetylenes in folium ginseng and radix ginseng by pressurized liquid extraction and high-performance liquid chromatography coupled with diode array detection and mass spectrometry

A rapid pressurized liquid extraction (PLE) and high-performance liquid chromatography coupled with diode array detection and mass spectrometry (HPLC-DAD-MS) method for the simultaneous determination of one flavonoid (panasenoside), nine saponins (ginsenoside Rg1, Re, Rf, Rg2, Rb1, Rc, Rb2, Rb3 and Rd) and two polyacetylenes (panaxydol and panaxynol) in folium ginseng and radix ginseng was developed. A Prevail C(18) rocket column (33 mm x 7 mm, 3.0 microm) and gradient elution were used during the analysis. Flavonoid was quantified at 355 nm, and saponins and polyacetylenes were determined at 203 nm. The chromatographic peaks of 12 investigated compounds in samples were unambiguously identified by compared their UV spectra and/or MS data with the related reference compounds. All calibration curves showed good linearity (r>0.999) within the test ranges. The intra- and inter-day variations for 12 analytes were less than 1.17% and 2.17%, respectively. The developed method was successfully applied to determine the investigated compounds in 10 samples of radix ginseng and folium ginseng, respectively. The result showed that PLE combined with rocket column HPLC analysis could provide a rapid method for analysis of compounds in traditional Chinese medicines (TCMs), which is helpful to comprehensive evaluation of quality of radix ginseng and folium ginseng.

In vivo and in vitro ethanol exposure in prenatal rat brain: GABA(B) receptor modulation on dopamine D(1) receptor and protein kinase A

We have investigated the effects of prenatal ethanol exposure on GABA(B) receptors (GABA(B)Rs), protein kinase A (PKA), and DA D(1) receptor (DAD(1)R) expressions. GABA(B1)R and GABA(B2)R showed different age-dependent expressions in in vivo fetal rat forebrain from gestational days (GD) 15.5 to 21.5 upon 10% ethanol treatment to mother, with and without baclofen at a dose of 10 mg/kg body weight/day. The protein level changes could not be attributed to changes in the level of transcription since GABA(B)R mRNA presented different expression patterns upon in vivo ethanol treatment. Using in vitro cultivated cortical neurons from GD 17.5 fetuses, we also explored the modulatory effects of ethanol on PKA and DAD(1)R through GABA(B)Rs, under 50 microM baclofen and 100 microM phaclofen administrations, with or without 100 mM of ethanol treatment in the culture media. The results showed that 20 min ethanol treatment without baclofen or phaclofen had increasing effects on both the GABA(B)Rs. Further, baclofen and phaclofen administration significantly affected PKA and GABA(B)R levels upon 20 min and 1 h ethanol treatment. In contrast, DAD(1)R showed increasing effects upon ethanol treatment, which was modulated by GABA(B)R's agonist baclofen and antagonist phaclofen. Therefore the present study suggested that the GABA(B)R activity could modulate ethanol's cellular effects, which possibly including PKA and DAD(1)R activities, and may be an underlying cause of ethanol's effects.

Spontaneous formation of highly ordered nanostructures: thermal instability and mode selection in surface-capped polymer films

We demonstrate a controllable formation process of wave-like patterns in thermally unstable surface-capped polymer films on a rigid substrate. Self-ordered wave-like structures over a large area can be created by applying a small lateral tension to the film, whereupon it becomes unstable. A clear mode selection process which includes creation, decay and interference between coexisting waves at different annealing conditions has been observed, which makes it possible to restrain the patterns which are formed finally. Our results provide a clear and new evidence of spinodal behaviour in such a film due to thermal instability. Furthermore, we show that the well-controlled patterns generated in such a process can be used to fabricate nanostructures for various applications.

A rapid method for simultaneous determination of 15 flavonoids in Epimedium using pressurized liquid extraction and ultra-performance liquid chromatography

Herba Epimedii (family Berberidaceae), Yinyanghuo in Chinese, is one of commonly used Chinese medicines. Flavonoids are considered as its active components. In this study, a rapid ultra-performance liquid chromatography (UPLC) method was developed for simultaneous determination of 15 flavonoids, including hexandraside E, kaempferol-3-O-rhamnoside, hexandraside F, epimedin A, epimedin B, epimedin C, icariin, epimedoside C, baohuoside II, caohuoside C, baohuoside VII, sagittatoside A, sagittatoside B, 2''-O-rhamnosyl icariside II and baohuoside I in different species of Epimedium. The analysis was performed on Waters Acquity UPLC system with an Acquity UPLC BEH C18 column (50 mm x 2.1mm I.D., 1.7 microm) and gradient elution of 50mM acetic acid aqueous solution and acetonitrile within 12 min. All calibration curves showed good linearity (R2>0.9997) within test ranges. The LOD and LOQ were lower than 0.13 and 0.52 ng on column, respectively. The R.S.D.s for intra- and inter-day of 15 analytes were less than 5.0% at three levels, and the recoveries were 95.0-103.7%. The validated method was successfully applied to quantitatively analyze 15 flavonoids in different species of Epimedium. The results showed there were great variations among the contents of investigated flavonoids. Hierarchical clustering analysis based on characteristics of 15 investigated compounds peaks in UPLC profiles showed that 37 samples were divided into 3 main clusters, which were in accordance with their flavonoids contents. The simulative mean chromatogram of the high content cluster was generated to compare the samples from different species and/or locations of Epimedium. Four flavonoids including epimedin A, B, C and icariin were selected as markers for quality control of the species of Epimedium used as Yinyanghuo.

Ethanol's effect on intracellular signal pathways in prenatal rat cortical neurons is GABAB1 dependent

To confirm the modulation role of GABA(B) on ethanol' effects, we studied the effects of ethanol on the neuronal intracellular signals, protein kinase A (PKA) and cAMP-response element binding protein (CREB), by using a system where GABA(B1) receptors were specifically knocked down in the in vitro cultivated cortical neurons. The results showed that the PKA alpha subunit was increased with ethanol treatment, and could be further increased by administering baclofen and phaclofen. By contrast, baclofen and/or phaclofen could decrease ethanol's up-regulation effects on PKA alpha subunit expression in primary cultured cortical neurons in which the GABA(B1) receptor was specifically knocked down using GABA(B1) receptor RNA interference. Furthermore, these effects could lead to changes of phospho (p)-CREB expression, which showed the same expression pattern as PKA. Finally, we observed changes of GABA(B1), PKA, and p-CREB distribution within the same neuronal cells. These results showed that the GABA(B) receptors are critical to ethanol's cellular effects, which occur via modulating the PKA and CREB transcription pathway, and may be an underlying cause of ethanol's effects.

Simultaneous determination of 15 flavonoids in Epimedium using pressurized liquid extraction and high-performance liquid chromatography

Herba Epimedii (family Berberidaceae), Yinyanghuo in Chinese, is one of the commonly used Chinese medicines. Flavonoids are considered as its active components. In this study, a reliable pressurized liquid extraction (PLE) and HPLC method was developed for simultaneous determination of 15 flavonoids, namely hexandraside E, kaempferol-3-O-rhamnoside, hexandraside F, epimedin A, epimedin B, epimedin C, icariin, epimedoside C, baohuoside II, caohuoside C, baohuoside VII, sagittatoside A, sagittatoside B, 2''-O-rhamnosyl icariside II and baohuoside I in different species of Epimedium. The analysis was performed by using a Zorbax SB-C18 analytical column (250 mm x 4.6 mm I.D., 5 microm) at gradient elution of water and acetonitrile with diode-array detection (270 nm). All calibration curves showed good linearity (r(2)>0.9997) within test ranges. The LOD and LOQ were lower than 1.31 ng and 2.62 ng on column, respectively. The RSD for intra- and inter-day of 15 analytes was less than 3.8% at three levels, and the recoveries were 90.5-106.8%. The validated method was successfully applied for the analysis of 15 flavonoids in different species of Epimedium which had great variation on the contents of investigated flavonoids. Hierarchical clustering analysis based on the characteristics of 15 investigated compound peaks in HPLC profiles showed that 26 samples were divided into three main clusters, which were in accordance with their flavonoid contents. Four flavonoids including epimedin A, B, C and icariin were optimized as markers for quality control of the species of Epimedium used as Yinyanghuo.

Determination of purine and pyrimidine bases in natural and cultured Cordyceps using optimum acid hydrolysis followed by high performance liquid chromatography

A method based on optimum acid hydrolysis followed by high-performance liquid chromatography (HPLC) with diode array detection was developed for quantitative determination of bio-available nucleosides, present as purine and pyrimidine bases including adenine, cytosine, guanine, hypoxanthine, thymine and uracil, in natural and cultured Cordyceps. It was found that the optimum conditions was hydrolyzing Cordyceps sample in eight folds of pure commercial perchloric acid for 1h at 95-100 degrees C. The determination was achieved by using a Zorbax SB-AQ analytical column (250 mm x 4.6 mm i.d., 5 microm) at gradient elution with diode-array detection. All calibration curves showed good linearity (r2>0.999) within test ranges. The developed method showed good repeatability for the quantification of six investigated nucleobases in Cordyceps with intra- and inter-day variations of less than 9.0 and 9.1%, respectively. The validated method was successfully applied to quantify bio-available nucleosides in natural and cultured Cordyceps, which is helpful to control their quality.

Qualitative and quantitative analyses of nucleosides and nucleobases in Ganoderma spp. by HPLC–DAD-MS

A high-performance liquid chromatography-diode array detector-mass spectrometry (HPLC-DAD-MS) analytical method was developed for detection of the nucleosides and nucleobases in two species of Lingzhi, the dried sporophore of Ganoderma lucidum and G. sinense. The method, combining advantages of both DAD and MS, was successfully used to qualitatively identify for six nucleosides namely, adenosine, cytidine, guanosine, inosine, thymidine, uridine and five nucleobases namely, adenine, guanine, hypoxanthine, thymine and uracil in Lingzhi samples. Quantitative analyses showed that uridine was the most abundant nucleoside in these Lingzhi samples and the contents of nine target analytes were found to be different in pileus and stipes of the fruiting bodies and among the different species of G. spp. The established method might apply as an alternative approach for the quality assessment of Lingzhi.

Macrophage biospecific extraction and high performance liquid chromatography for hypothesis of immunological active components in Cordyceps sinensis

A method, namely macrophage biospecific extraction and high performance liquid chromatography for screening potential immunological active components in Cordyceps sinensis, a well-known traditional Chinese medicine, was developed. Two components, which could interact with macrophage, in aqueous extract of C. sinensis (WECS) were found by comparing the HPLC chromatograms of WECS before and after interacted with macrophage. The two compounds were identified as guanosine and adenosine. Their effects on mice macrophage were also investigated in vitro. The results showed that adenosine and guanosine could attenuate NO (p<0.01) but augment interleukin-lbeta (IL-1beta) (p<0.05) release of macrophage during the tested concentrations. In addition, guanosine (0.10 micromol/ml) also increased alpha-tumor necrosis factor (TNF-alpha) release of macrophage. The data suggest that macrophage biospecific extraction and HPLC is a useful method to screen immunological active components from Chinese medicines.