Variable expression of the Fragile X Mental Retardation 1 (FMR1) gene in patients with premature ovarian failure syndrome is not dependent on number of (CGG)n triplets in exon 1

BACKGROUND

Increased expression of the Fragile X Mental Retardation 1 (FMR1) gene in blood cells has been claimed to be associated with variable (CGG)(n) triplet numbers in the 5' untranslated region of this gene. Increased CGG triplet numbers, including that of the so-called premutation range (n= 55-200), were shown to have a risk of <26% to impair ovarian reserve leading to primary ovarian insufficiency and premature ovarian failure (POF).

METHODS

DNA and RNA samples were isolated from 74 patients with idiopathic POF to evaluate quantitatively the expression of FMR1 in leukocytes and CGG triplet number on FMR1 gene alleles. mRNA levels were normalized and compared with those of control women. Expression of the encoded protein (FMRP) was analysed by immunohistochemistry on ovarian biopsy tissue sections.

RESULTS

A large variance of the FMR1 transcript level was found in the leukocyte RNA samples, but only in patients with POF, and this variability did not correlate to variance of CGG triplet numbers found on both FMR1 alleles (19 < n > 90). During normal folliculogenesis, FMRP is predominantly expressed in granulosa cells.

CONCLUSIONS

Our data suggest that FMR1 expression during human folliculogenesis is probably a quantitative trait. Proper function of FMRP in granulosa cells seems to depend on an optimal transcript level. All women with CGG triplet numbers outside the range associated with normal folliculogenesis (26 < n > 34) are therefore expected to have a relaxed FMR1 transcription control. FMR1 transcript levels in leukocytes might therefore be diagnostic for altered FMRP levels in granulosa cells, which will affect the process of folliculogenesis.

Exploring the role of phase modulation on photoluminescence yield

We report an investigation to elucidate the mechanisms of control in phase-sensitive experiments in two molecular systems. A first inspection of optimization procedures yields the same experimental result: increase in the emission efficiency upon excitation by a phase modulated pulse in a two-photon transition. More detailed studies, which include power dependence, spectral response, one and two color pump-probe and pump-pump experiments show that while for one chromophore phase modulation leads to spectral matching between the two-photon cross section and the second order power spectrum for the other it provides a tool to manipulate the wavepacket dynamics in the excited state.

Human papillomavirus is detectable in Barrett's esophagus and esophageal carcinoma but is unlikely to be of any etiologic significance

Barrett's esophagus (BE), a known precursor of esophageal adenocarcinoma has recently been associated with human papillomavirus (HPV). p16(INK4a) expression is a recognized surrogate marker of HPV infection in the cervix.

OBJECTIVES

This study has assessed the possible role of human papillomavirus (HPV) infection in BE and esophageal adenocarcinoma, in the North American population by screening esophageal tissues for HPV by a combination of assays.

STUDY DESIGN

Formalin-fixed, paraffin-embedded blocks from cases of Barrett's esophagus (n=84), esophageal adenocarcinoma (n=36) and normal gastro-esophageal junction (n=29) were examined for HPV by PCR, chromogenic in situ hybridization, and p16(INK4a) immunohistochemistry.

RESULTS

HPV DNA was detected by PCR in 23 of 84 (27.4%) BE cases, 11 of 36 (31%) cases of adenocarcinoma and in 7 of 29 (24%) normal control cases (p=0.82). p16(INK4a) staining was positive in 10 (12%) cases of BE, 15 (42%) cases of adenocarcinoma and 6 (21%) cases of the control group. Positive p16(INK4a) staining was not statistically different between the three groups whether positive or negative for HPV DNA (p=0.91 and p=0.91 respectively). Similarly, negative p16(INK4a) staining did not show a difference between the three groups for whether positive or negative for HPV DNA (p=0.50 and p=0.28, respectively). HPV was not detected by CISH in the adenocarcinomas while in BE and control groups, CISH was non-contributory.

CONCLUSIONS

These data suggest that while HPV is detectable in a subset of esophageal lesions and tumors, the HPV detected is unlikely to be of etiologic significance or a factor accounting for the increase in BE and esophageal adenocarcinoma cases in the United States.

Abstract P6-15-20: Development of PEA-15-Based Therapy in Breast Cancer in a Preclinical Study

Background: PEA-15 (phosphoprotein enriched in astrocytes, 15 kDa) has tumor suppressor properties in both breast and ovarian cancer cells. Overexpression of PEA-15 in MDA-MB-468 triple-negative breast cancer cells using adenoviral vector (Ad.PEA-15) inhibited cell growth by inducing apoptosis. Treatment with Ad.PEA-15 led to significant regression of tumors in mice, indicating that PEA-15 could have therapeutic potential in breast cancer. PEA-15 exerts its antitumor activity by binding to ERK in the cytoplasm and preventing its translocation into the nucleus, thereby inhibiting ERK-dependent transcription and cell proliferation. Because ERK inhibitors have been shown to be toxic, in this study, we developed PEA-15 mimetic peptides as a therapeutic agent in breast cancer. These peptides, which are expected to be less toxic because of their ability to mimic PEA-15, are proposed to inhibit cell proliferation by sequestering ERK in the cytoplasm.

Material and Methods: PEA-15 mimetic peptides were designed and synthesized based on structural analysis of linear segments from the C-terminal end of PEA-15, which is one of the two regions that are presumably critical for ERK binding, using nuclear magnetic resonance spectroscopy. These synthetic peptides were labeled with FAM to enable determination of their subcellular localization. The PULSin reagent was used as a delivery reagent for peptide penetration into cancer cells. The penetration ability of these peptides into HeLa and MDA-MB-468 cells was analyzed by fluorescence microscope and fluorescence-activated cell sorting. Their effect on ERK subcellular localization was examined by cell-fractionation analysis. Their impact on cell survival was determined by trypan blue viability assay and propidium iodide staining. Results: Ten peptides were designed and synthesized based on the C-terminal segments of PEA-15. Three of these FAM-labeled synthetic peptides delivered with the PULSin reagent were able to penetrate HeLa and MDA-MB-468 cells with 80-90% and 30-40% efficiency, respectively. Further, these peptides redirected ERK into the cytoplasm from the nucleus in MDA-MB-468 cells and caused 31% reduction in viability of HeLa cells as compared to the untreated control. Ongoing studies are evaluating PEA-15 peptides for their ability to interact with ERK using ELISA. In the future, we will also test their therapeutic efficacy and safety using a xenograft breast cancer model.

Discussion: Previous studies revealed that PEA-15 has antitumor activity against breast and ovarian cancer cells by sequestering ERK in the cytoplasm. Due to the toxicity of ERK enzymatic inhibitors, we developed PEA-15 mimetic peptides and demonstrated their therapeutic potential for breast cancer, which may provide opportunities for breast cancer patients who currently have limited treatment options.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P6-15-20.

The association between internet addiction and self-injurious behaviour among adolescents

OBJECTIVE

To examine the association between internet addiction and self-injurious behaviour (SIB) in adolescence.

METHODS

Population-based cross-sectional survey of 1618 high school students aged 13-18 years in Guangzhou city, Guangdong Province, PR China. Deliberate SIB was measured using self-reported questionnaire; internet addiction was assessed using the Internet Addiction Test (IAT).

RESULTS

263 (16.3%) participants reported having committed some form of SIB in the past 6 months. 73 (4.5%) had committed SIB 6 times or more, and 157 (9.7%) 1-5 times. The majority of respondents were classified as normal users of the internet (n = 1392, 89.2%), with 158 (10.2%) moderately and 10 (0.6%) severely addicted to the internet. After adjusting for potential confounders, the odds ratio for SIB was 2.0 (95% CI 1.1 to 3.7) for those who were classified as moderately and severely addicted to the internet when compared to the normal group.

CONCLUSIONS

SIB is common in adolescence in the study population in China. Addiction to the internet is detrimental to mental health and increases the risk of self-injury among adolescents. Clinicians need to be aware of potential co-morbidities of other addictions among adolescent self-injured patients.

HPV DNA is associated with a subset of Schneiderian papillomas but does not correlate with p16(INK4a) immunoreactivity

This study investigated the role of human papillomavirus (HPV) in Schneiderian papillomas (SPs) to determine whether HPV is associated with the pathogenesis of particular histologic subtypes and whether p16(INK4a) can be used as a surrogate marker for HPV detection. Twenty-seven papilloma specimens (19 inverted [IPs], 6 exophytic [EPs], 1 oncocytic [OP] and 1 mixed) were collected from 23 patients. Purified SP DNA extracts were tested for HPV by PCR using GP5 +/GP6 + primers; HPV genotyping was performed by dot blot hybridization. PCR positive specimens were screened for HPV by biotinyl-tyramide-based chromogenic in situ hybridization (CISH). Immunohistochemsistry (IHC) for the HPV L1 capsid protein and for p16(INK4a) was performed on all specimens. HPV was detected by PCR in 16/27 (59.3%) SPs; 9/19 (47.4%) IPs; 6/6 (100%) EPs [p = 0.051], and 1/1 (100%) mixed SP. HPV was not detected in the single OP. High risk genotypes were detected in 4/9 IPs (44.4%) and 0/6 EPs (0%) [p = 0.10]. Seven of 16 PCR positive SPs were also CISH positive for HPV: 5/6 EPs (83.3%) and 1/9 IP (11.1%) [p = 0.01]. IHC for the L1 capsid protein was positive in 2 SPs (1 EP and 1 mixed). p16(INK4a) staining was seen in 14/16 (87.5%) PCR positive SPs and in 10/11 (90.9%) PCR negative SPs (p = 1.00). In summary, this study demonstrates a strong association between HPV and EPs, however, its role in IPs remains less well-defined. Further, p16(INK4a) is not a useful surrogate marker for HPV detection across the various SPs.

Identification of brassinosteroid responsive genes in Arabidopsis by cDNA array

We have systematically monitored brassinosteroid (BR) responsive genes in a BR-deficient mutant det2 suspension culture of Arabidopsis by using a cDNA array approach. Among 13000 cDNA clones arrayed on filters, 53 BR responsive clones were identified and designated BRR1-BRR53. Sequence analysis of 43 clones showed that 19 clones are novel genes, 3 clones are genes involved in the control of cell division, 4 clones are genes related to plant stress responses, 4 clones are transcriptional factor or signal transduction component genes, and 3 clones are genes involved in RNA splicing or structure forming. In addition, we also found that BR regulated the transcription of genes related to many physiological processes, such as photoreaction, ion transportation and some metabolic processes. These findings present molecular evidence that BR plays an essential role in plant growth and development.

Computer-aided detection (CAD) and assessment of malignant lesions in the liver and lung using a novel PET/CT software tool: initial results

PURPOSE

To determine the feasibility of a PET/CT software tool (PET computer-aided detection: PET-CAD) for automated detection and assessment of pulmonary and hepatic lesions.

MATERIALS AND METHODS

20 consecutive patients with colorectal liver metastases and 20 consecutive patients suffering from non-small cell lung cancer (NSCLC) were examined with FDG-PET/CT. In a first step the maximum standardized uptake values (SUV (max)) of non-tumorous liver and lung tissues were determined manually. This value was used as a threshold value for software-based lesion detection. The number of lesions detected, their SUV (max), and their sizes in the x, y, and z-planes, as automatically provided by PET-CAD, were compared to visual lesion detection and manual measurements on CT.

RESULTS

The sensitivity for automated detection was 96 % (86 - 99 %) for colorectal liver metastases and 90 % (70 - 99 %) for lung lesions. The positive predictive value was 80 % for liver and 68 % for lung lesions. The mean SUV (max) of all lung lesions was 9.3 and 8.8 for the liver lesions. When assessed by PET-CAD, the mean lesion sizes for liver lesions in the x, y, and z-planes were 4.3 cm, 4.6 cm, and 4.2 cm compared to 3.5 cm, 3.8 cm, and 3.6 cm for manual measurements. The mean lesion sizes of lung lesions were 7.4 cm, 7.7 cm, and 8.4 cm in the x, y, and z-planes when assessed by PET-CAD compared to 5.8 cm, 6.1 cm, and 7.1 cm when measured manually. Using manual assessment, the lesion sizes were significantly smaller in all planes (p < 0.005).

CONCLUSION

Software tools for automated lesion detection and assessment are expected to improve the clinical PET/CT workflow. Before implementation in the clinical routine, further improvements to the measurement accuracy are required.

Preparation and photocatalytic property of TiO2-Fe3O4 core-shell nanoparticles

Titanium dioxide is an attractive photocatalytic material with a wide band gap which can be applied in chemical processes to degrade organic compounds. When TiO2 nanoparticles are dispersed in water solution in suspended state they possess high photocatalytic activity, resulting in effectively degrading the hazardous compounds in wastewater. But when the TiO2 nanoparticles are used in suspension state, it is very difficult to get them back and make them reuse, which would limit their application due to the cost. Here, we report the preparation of reusable TiO2 composite nanoparticles with a core-shell structure, which consist of a nanosized Fe3O4 core and the encapsulated TiO2 shell. The experimental result shows that these nanoparticles can be used in suspended state and exhibit high photocatalytic activity. In addition, the photocatalytic nanoparticles with core-shell structure can be easily withdrawn with a magnetic field.

Biomimetic characterisation of key surface parameters for the development of fouling resistant materials

Material science provides a direct route to developing a new generation of non-toxic, surface effect-based antifouling technologies with applications ranging from biomedical science to marine transport. The surface topography of materials directly affects fouling resistance and fouling removal, the two key mechanisms for antifouling technologies. However, the field is hindered by the lack of quantified surface characteristics to guide the development of new antifouling materials. Using a biomimetic approach, key surface parameters are defined and quantified and correlated with fouling resistance and fouling removal from the shells of marine molluscs. Laser scanning confocal microscopy was used to acquire images for quantitative surface characterisation using three-dimensional surface parameters, and field assays correlated these with fouling resistance and fouling release. Principle component analysis produced a major component (explaining 54% of total variation between shell surfaces) that correlated with fouling resistance. The five surface parameters positively correlated to increased fouling resistance were, in order of importance, low fractal dimension, high skewness of both the roughness and waviness profiles, higher values of isotropy and lower values of mean surface roughness. The second component (accounting for 20% of variation between shells) positively correlated to fouling release, for which higher values of mean waviness almost exclusively dictated this relationship. This study provides quantified surface parameters to guide the development of new materials with surface properties that confer fouling resistance and release.

Combination of CsA, MTX and low-dose, short-course mycophenolate mofetil for GVHD prophylaxis

In an effort to reduce the incidence and severity of acute GVHD (aGVHD), we have developed a new prophylaxis regimen combining cyclosporine and MTX with a short 30-day course of low-dose (500 mg per day) mycophenolate mofetil. This regimen was studied prospectively 100 patients undergoing HLA-matched and 1-antigen-mismatched allogeneic peripheral blood SCT from related donors. The cumulative incidence of aGVHD was 16% (grades II-IV (9.5%) and grades III-IV (1%)). The cumulative incidence of chronic GVHD (cGVHD) was 53% with 28% extensive cGVHD. The cumulative incidence of transplant-related mortality at 100 days and 3 years were 6 and 13%. The estimated probabilities of disease-free survival at 3 years in standard- and high-risk patients were 77 and 30%, respectively (P<0.0001). The estimated probabilities of overall survival at 3 years in standard- and high-risk patients were 77 and 37%, respectively (P<0.0001). These data show a substantial decrease in the risk of developing aGVHD without an increase in relapse or any adverse impact on survival in standard-risk patients.

Dynamic seizure-related changes in extracellular signal-regulated kinase activation in a mouse model of temporal lobe epilepsy

Extracellular signal-regulated kinase (ERK) is highly sensitive to regulation by neuronal activity and is critically involved in several forms of synaptic plasticity. These features suggested that alterations in ERK signaling might occur in epilepsy. Previous studies have described increased ERK phosphorylation immediately after the induction of severe seizures, but patterns of ERK activation in epileptic animals during the chronic period have not been determined. Thus, the localization and abundance of phosphorylated extracellular signal-regulated kinase (pERK) were examined in a pilocarpine model of recurrent seizures in C57BL/6 mice during the seizure-free period and at short intervals after spontaneous seizures. Immunolabeling of pERK in control animals revealed an abundance of distinctly-labeled neurons within the hippocampal formation. However, in pilocarpine-treated mice during the seizure-free period, the numbers of pERK-labeled neurons were substantially decreased throughout much of the hippocampal formation. Double labeling with a general neuronal marker suggested that the decrease in pERK-labeled neurons was not due primarily to cell loss. The decreased ERK phosphorylation in seizure-prone animals was interpreted as a compensatory response to increased neuronal excitability within the network. Nevertheless, striking increases in pERK labeling occurred at the time of spontaneous seizures and were evident in large populations of neurons at very short intervals (as early as 2 min) after detection of a behavioral seizure. These findings suggest that increased pERK labeling could be one of the earliest immunohistochemical indicators of neurons that are activated at the time of a spontaneous seizure.