Noninvasive detection of graft rejection by in vivo (19) F MRI in the early stage

Diagnosis of transplant rejection requires tissue biopsy and entails risks. Here, we describe a new (19) F MRI approach for noninvasive visualization of organ rejection via the macrophage host response. For this, we employed biochemically inert emulsified perfluorocarbons (PFCs), known to be preferentially phagocytized by monocytes and macrophages. Isografts from C57BL/6 or allografts from C57B10.A mice were heterotopically transplanted into C57BL/6 recipients. PFCs were applied intravenously followed by (1) H/(19) F MRI at 9.4 T 24 h after injection. (1) H images showed a similar position and anatomy of the graft in the abdomen for both cases. However, corresponding (19) F signals were only observed in allogenic tissue. (1) H/(19) F MRI enabled us to detect the initial immune response not later than 3 days after surgery, when conventional parameters did not reveal any signs of rejection. In allografts, the observed (19) F signal strongly increased with time and correlated with the extent of rejection. In separate experiments, rapamycin was used to demonstrate the ability of (19) F MRI to monitor immunosuppressive therapy. Thus, PFCs can serve as positive contrast agent for the early detection of transplant rejection by (19) F MRI with high spatial resolution and an excellent degree of specificity due to lack of any (19) F background.

Using high-resolution MR imaging at 7T to evaluate the anatomy of the midbrain dopaminergic system

BACKGROUND AND PURPOSE

Dysfunction of DA neurotransmission from the SN and VTA has been implicated in neuropsychiatric diseases, including Parkinson disease and schizophrenia. Unfortunately, these midbrain DA structures are difficult to define on clinical MR imaging. To more precisely evaluate the anatomic architecture of the DA midbrain, we scanned healthy participants with a 7T MR imaging system. Here we contrast the performance of high-resolution T2- and T2*-weighted GRASE and FFE MR imaging scans at 7T.

MATERIALS AND METHODS

Ten healthy participants were scanned by using GRASE and FFE sequences. CNRs were calculated among the SN, VTA, and RN, and their volumes were estimated by using a segmentation algorithm.

RESULTS

Both GRASE and FFE scans revealed visible contrast between midbrain DA regions. The GRASE scan showed higher CNRs compared with the FFE scan. The T2* contrast of the FFE scan further delineated substructures and microvasculature within the midbrain SN and RN. Segmentation and volume estimation of the midbrain SN, RN, and VTA showed individual differences in the size and volume of these structures across participants.

CONCLUSIONS

Both GRASE and FFE provide sufficient CNR to evaluate the anatomy of the midbrain DA system. The FFE in particular reveals vascular details and substructure information within the midbrain regions that could be useful for examining structural changes in midbrain pathologies.

Abstract P3-08-02: Pharmacogenomic Predictors of Patient Response to Chemotherapy Derived from Breast Cancer Cell Lines Combining Knowledge-Based and Data-Driven Methods

Background: Responses of breast cancer patients to chemotherapy treatments vary considerably, and population treatment response rates remain low. To improve patient outcomes, genomic profiles have been used to identify patients who would benefit from specific treatments. Several studies have used cancer cell lines to develop pharmacogenomic predictors by identifying genes associated with drug response. However, pharmacogenomic predictors derived by this data-driven approach may not readily elucidate the underlying mechanisms associated with drug responses, because the identified predictors by computational methods may not directly associate with drug responses considering the complex genetic regulatory network. To overcome this issue, we proposed a strategy to integrate data-driven methods with biological knowledge-based approaches to identify genomic predictors. We then applied this approach to breast cancer cell lines to identify genomic predictors of paclitaxel-5-fluorouracil-doxorubicin-cyclophosphamide (TFAC), the identified predictors are then evaluated by their ability to predict the clinical outcome of the breast cancer patients who are treated by TFAC. Material: Thirty immortalized breast cancer cell lines were exposed to various concentrations of TFAC using a chemosensitivity assay. Area under the dose-response curves was calculated to measure chemoresponses. Gene expression profiles of the 30 cell lines, the expression profiles as well as the pathologic complete response (pCR) information of 133 breast cancer patients treated by TFAC were publicly available. Methods: We performed pathway enrichment analysis in breast cancer cell lines to assess the association between drug response and curated gene sets predefined by molecular signature database. Pathways with p-value less than 0.01 were considered enriched. The genes from the enriched pathways whose expression values were highly correlated with drug sensitivity were selected as the pharmacogenomic predictors. To validate these predictors, the performances of their prediction for patients’ pCR were evaluated using principle component regression method.

Results: Using pathway enrichment analysis, 17 pathways were identified to be related to TFAC drug response. These pathways are related to different biological functions, including breast cancer ER status and BRCA type, immune response, differentiation, and drug response. Using supervised principal component regression, 59 genes involved in at least one of these 17 pathways were selected as genomic predictors. The prediction accuracy of patient pCR was 0.70, sensitivity was 0.71, and specificity was 0.70. Conclusion: By combining knowledge-based and data-driven methods, we have identified 59 genes from breast cancer cell lines as pharmacogenomic predictors of drug response to TFAC. These results support the viability of using breast cancer cell lines to predict breast cancer patient response to chemotherapy. Further functional study of these pharmacogenomic predictors will extend our understanding of individual drug response and facilitate personalized treatment.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P3-08-02.

Abstract P2-09-10: Feasibility Assessment of Pharmacogenomic Predictors Developed from Breast Cancer Cell Lines To Predict Breast Cancer Patient Pathological Response in Neoadjuvant Chemotherapy

Background: Studies of developing pharmacogenomic predictors from cancer cell lines to predict cancer patient clinical response and outcome to chemotherapy have yielded both positive and negative results. The variability in these results may arise from the noise inherent of microarray technology as well as the small sample size of in cell line studies. Therefore, it is greatly needed to evaluate the feasibility of using cell lines to develop pharmacogenomic predictors of patient pathological response. Material and Methods: Thirty breast cancer cell lines were exposed to 10 concentrations of paclitaxel-5-fluorouracil-doxorubicin-cyclophosphamide (TFAC) to measure in vitro chemosensitivity. Two independent and publicly available microarray datasets (Hoeflich and Neve) on these breast cancer cell lines together with the chemosensitivity results were used to identify pharmacogenomic predictors from each dataset. Two independent clinical trials (Hess and Popovici) with publically available data, having 130 and 100 patients respectively, were used as test sets to validate the accuracy of the pharmacogenomic predictors. All patients received TFAC as neoadjuvant therapy and the gene expression profiles of patients were assessed before receiving chemotherapy treatment. The patient's pathological complete response (pCR) was determined after treatment to evaluate the chemotherapy efficacy.

The pharmacogenomic predictors developed from each of the cell line studies were evaluated for their ability to predict patient pCR in each of the clinical trials using the supervised principle component regression method.

Results: The pharmacogenomic predictors identified from the Hoeflich and Neve cell line data (training sets) predicted pCR of the patients in the two clinical trials (test sets) with 64%-68% accuracy, 70%-87% sensitivity, and 60%-67% specificity when 100 genes were selected as pharmacogenomic predictors (Table 1).

Conclusions: The four independent prediction results generated in this study demonstrate the feasibility of using breast cancer cell lines to identify pharmacogenomic predictors of response to chemotherapy treatment for breast cancer patients. Future studies will examine the use of drug responses from primary cultures of patient tumors to develop pharmacogenomic predictors of breast cancer patient responses to chemotherapy treatment.

Table 1. Prediction of breast cancer patients’ pCR by pharmacogenomic predictors derived from breast cancer cell lines.

Genetics and vaccine efficacy: host genetic variation affecting Marek's disease vaccine efficacy in White Leghorn chickens

Marek's disease (MD) is a T-cell lymphoma disease of domestic chickens induced by MD virus (MDV), a naturally oncogenic and highly contagious cell-associated α-herpesvirus. Earlier reports have shown that the MHC haplotype as well as non-MHC genes are responsible for genetic resistance to MD. The MHC was also shown to affect efficiency of vaccine response. Using specific-pathogen-free chickens from a series of 19 recombinant congenic strains and their 2 progenitor lines (lines 6(3) and 7(2)), vaccine challenge experiments were conducted to examine the effect of host genetic variation on vaccine efficacy. The 21 inbred lines of White Leghorns share the same B*2 MHC haplotype and the genome of each recombinant congenic strain differs by a random 1/8 sample of the susceptible donor line (7(2)) genome. Chickens from each of the lines were divided into 2 groups. One was vaccinated with turkey herpesvirus strain FC126 at the day of hatch and the other was treated as a nonvaccinated control. Chickens of both groups were inoculated with a very virulent plus strain of MDV on the fifth day posthatch. Analyses of the MD data showed that the genetic line significantly influenced MD incidence and days of survival post-MDV infection after vaccination of chickens (P<0.01). The protective indices against MD varied greatly among the lines with a range of 0 up to 84%. This is the first evidence that non-MHC host genetic variation significantly affects MD vaccine efficacy in chickens in a designed prospective study.

Research of thoracolumbar spine lateral vascular anatomy and imaging

This study introduces an anatomical basis for surgeries such as thoracoscope-assisted thoracolumbar spinal anterior interbody fusion in terms of image observing and corpse specimen anatomising. The observation of the 3-dimensional computed tomography (CT) image indicates that segmental arteries are visible and run in the central supersulcus of the corresponding vertebral body's side, while the branches are invisible. The distances between adjacent segmental arteries in T(10/11), T(11/12), T₁₂/L₁, L(1/2), and L(2/3) are 23.35 ± 1.48, 25.61 ± 2.08, 29.12 ± 2.30, 32.53 ± 2.18, and 33.73 ± 2.29 (mm), respectively. And the observation by the thoracolumbar spine side of the adult corpse specimens shows that segmental arteries and veins constantly exist and run in the central supersulcus of the corresponding vertebral body's side; each segmental artery has some small branches; the zone between the upper and lower segmental arteries form a relatively non-vascular nerve safe zone, where the intervertebral space (disc) locates. The distances between adjacent segmental arteries in T(10/11), T(11/12), T₁₂/L₁, L(1/2), L(2/3) are 23.34 ± 0.78, 25.54 ± 0.85, 29.11 ± 1.01, 32.82 ± ± 1.28, and 33.71 ± 1.42 (mm), respectively. The safe zone, with the intervertebral disc as the reference mark, can provide enough operation space for surgeries like thoracoscope-assisted anterior interbody fusion and reducing damage to blood vessels as well as surgical complications. Additionally, the arrangement and distribution of segmental arteries can be clearly displayed on the 3-dimensional CT image and the result is basically consistent with that of corpse specimens. Therefore, the 3-dimensional CT image can be regarded as the reference for video-assisted thoracoscopic surgery plans.

Lentivirus-mediated expression of MxA in chicken spermatogonial stem cells

The aim of this study was to construct a lentivirus vector that carries the human myxovirus-resistant A (MxA) anti-virus gene for efficiently infecting rooster spermatogonial stem cells (SSCs). A lentiviral vector carrying the enhanced green fluorescent protein (EGFP) and MxA fusion gene (EGFP-MxA) was constructed using TOPO technology in this study. Enhanced green fluorescent protein-MxA was inserted in the right orientation as determined by restriction enzyme digest. No gene recombination in the vector occurred. After infecting 293FT cells, EGFP-MxA fusion protein was expressed as granular green fluorescence characteristic of EGFP-MxA expression, suggesting that the TOPO expression vector was properly constructed and the fusion protein expressed correctly. The EGFP-MxA recombinant lentivirus was packaged by cotransfecting 293FT cells with EGFP-MxA and the packaging plasmids. We also purified SSCs from testicle tissues from 25-day-old roosters for infection with the EGFP-MxA recombinant virus. After infecting rooster SSCs with the recombinant virus for 72 h, EGFP-MxA expression was detected by EGFP expression. Enhanced green fluorescent protein-MxA expression in SSCs was further confirmed at the transcription level by RT-PCR and at the protein level by immunocytochemistry. Staining with Hoechst 33342 showed that infected SSCs differed from the sertoli cells. Similar to stem cells, SSCs were positive for alkaline phosphoric acid enzyme and for stage-specific embryonic antigen-1 stem cell factor. The results demonstrated that the recombinant virus made in our study can infect rooster SSCs efficiently to express the anti-virus protein MxA, establishing the basis of transferring MxA into SSCs to obtain virus-resistant, genetically-modified roosters.

Sonographic value in diagnosis of hemorrhagic ovarian cysts

PURPOSE

To investigate the sonographic characteristics of hemorrhagic ovarian cysts (HOC) and to avoid unnecessary surgery.

METHODS

113 cases of suspected HOC underwent sonographic and clinical follow-up for three months.

RESULTS

104 cases were clinically diagnosed with HOC as the masses disappeared naturally. The mean length of the greatest diameter was 5.12 +/- 1.33 cm, and the mean period of disappearance was 3.5 +/- 2.4 weeks. There were four patterns of the image: 21 cases (20.2%) showed a diffused dense echo pattern, 25 cases (24.0%) displayed a mixed pattern, 30 cases (28.8%) expressed a sponge-like pattern and 28 cases (27.0%) exhibited a cystic pattern. Ring blood flow with high velocity and low resistance was detected in 41 cases (40%) and there was no internal blood flow.

CONCLUSION

HOC showed characteristic features on sonography, which provided useful information to differentiate HOC from ovarian tumors.

Use of Ligasure™ Bipolar Diathermy System in vaginal hysterectomy

The use of Ligasure, a computer-controlled bipolar diathermy system is proven beneficial in a wide range of surgical procedures. This study was to evaluate its application to vaginal hysterectomy. Over forty patients underwent vaginal hysterectomy with (n = 32) or without (n = 12) Ligasure using standard surgical techniques. The main diagnoses, the age of patients, time for surgery, hospital stay and estimated blood loss during operation were compared. The average operating time was shorter in the Ligasure vaginal hysterectomy group (30 mins (24-48) P < 0.05), the estimated blood loss was less in the Ligasure hysterectomy group (39 mins (25-60) P < 0.05), and the hospital stay was shorter in the Ligasure hysterectomy group (1.2 days (1-2) vs 3 days (3-5) P < 0.05). There were no postoperative complications or re-admissions in either group. Vaginal hysterectomy using Ligasure reduced operating time and blood loss, and therefore shortened hospital stay.

Immune modulation by adjuvants combined with diphtheria toxoid administered topically in BALB/c mice after microneedle array pretreatment

Purpose

In this study, modulation of the immune response against diphtheria toxoid (DT) by various adjuvants in transcutaneous immunization (TCI) with microneedle array pretreatment was investigated.

Methods

TCI was performed on BALB/c mice with or without microneedle array pretreatment using DT as a model antigen co-administrated with lipopolysaccharide (LPS), Quil A, CpG oligo deoxynucleotide (CpG) or cholera toxin (CT) as adjuvant. The immunogenicity was evaluated by measuring serum IgG subtype titers and neutralizing antibody titers.

Results

TCI with microneedle array pretreatment resulted in a 1,000-fold increase of DT-specific serum IgG levels as compared to TCI. The immune response was further improved by co-administration of adjuvants, showing a progressive increase in serum IgG titers when adjuvanted with LPS, Quil A, CpG and CT. IgG titers of the CT-adjuvanted group reached levels comparable to those obtained after DT-alum subcutaneous injection. The IgG1/IgG2a ratio of DT-specific antibodies decreased in the following sequence: plain DT, Quil A, CT and CpG, suggesting that the immune response was skewed towards the Th1 direction.

Conclusions

The potency and the quality of the immune response against DT administered by microneedle array mediated TCI can be modulated by co-administration of adjuvants.

Glial fibrillary acidic protein promoter targets pancreatic stellate cells

BACKGROUND

Pancreatic fibrosis is one of the clinical manifestations of chronic pancreatitis and pancreatic cancer. Pancreatic stellate cells (PSCs) have been recognised as principal effector cells in the development of pancreatic fibrosis. The ability to specifically address PSCs might offer a potential for developing a targeted therapy for pancreatic fibrosis.

AIM

Characterisation of the 2.2kb hGFAP (human glial fibrillary acidic protein) promoter for its usefulness to express reporter genes specifically in PSCs in vitro and in vivo.

METHODS

2.2kb hGFAP-LacZ reporter expressions were examined in four immortalised PSC lines and two non-PSCs, meanwhile, GFAP-LacZ transgenic mice were used to detect LacZ reporter in pancreas tissue. Several kinase inhibitors, vitamin A and its metabolites were applied to study the regulation of 2.2kb hGFAP promoter in PSCs.

RESULTS

Our results showed that the 2.2kb hGFAP promoter is capable of regulating the expression of reporter genes exclusively in immortalised and primary PSCs, as well as in PSCs of transgenic GFAP-LacZ mice. When a PSC cell line transfected with the LacZ reporter (SAM-K/LacZ/C1) was treated with different anti-fibrotic agents and kinase inhibitors, the transgenic beta-galactosidase activity was found to be regulated by multiple signalling pathways known to be involved in the PSC activation.

CONCLUSIONS

This study provides the proof of concept for using the 2.2kb hGFAP promoter to specifically manipulate PSCs for the development of targeted gene and/or drug therapy in pancreatic fibrosis, and for the screening of anti-fibrotic agents.

Pten and p53 converge on c-Myc to control differentiation, self-renewal, and transformation of normal and neoplastic stem cells in glioblastoma

Glioblastoma (GBM) is a highly lethal primary brain cancer with hallmark features of diffuse invasion, intense apoptosis resistance and florid necrosis, robust angiogenesis, and an immature profile with developmental plasticity. In the course of assessing the developmental consequences of central nervous system (CNS)-specific deletion of p53 and Pten, we observed a penetrant acute-onset malignant glioma phenotype with striking clinical, pathological, and molecular resemblance to primary GBM in humans. This primary, as opposed to secondary, GBM presentation in the mouse prompted genetic analysis of human primary GBM samples that revealed combined p53 and Pten mutations as the most common tumor suppressor defects in primary GBM. On the mechanistic level, the "multiforme" histopathological presentation and immature differentiation marker profile of the murine tumors motivated transcriptomic promoter-binding element and functional studies of neural stem cells (NSCs), which revealed that dual, but not singular, inactivation of p53 and Pten promotes cellular c-Myc activation. This increased c-Myc activity is associated not only with impaired differentiation, enhanced self-renewal capacity of NSCs, and tumor-initiating cells (TICs), but also with maintenance of TIC tumorigenic potential. Together, these murine studies have provided a highly faithful model of primary GBM, revealed a common tumor suppressor mutational pattern in human disease, and established c-Myc as a key component of p53 and Pten cooperative actions in the regulation of normal and malignant stem/progenitor cell differentiation, self-renewal, and tumorigenic potential.

Expression of tubulin, p53, ki67, receptors for estrogen, and progesterone in endometrial cancer

OBJECTIVE

We aimed at investigating by immunohistochemistry the relationship between tubulin and histological features of tumors, estrogen receptors (ER), progesterone receptors (PR), expression of p53, and Ki67 in a series of 84 primary untreated endometrial cancer patients.

METHODS

Immunohistochemistry was performed on paraffin-embedded sections by using rabbit polyclonal antiserum against human class III beta-tubulin, anti-ER, anti-PR, anti Ki67 and p53 monoclonal antibodies.

RESULTS

Expression of class III beta-tubulin in proliferative phase endometrium was significantly higher than that in the secretory phase (X2 = 5.49, p value = 0.029). There was no difference in the distribution of tubulin positive cases between normal endometrium and endometrial carcinoma (X2 = 0.46, p value > 0.05). The immunostaining pattern of tubulin did not correlate with age, clinical stage, histological grade, depth of invasion, or expression of p53, Ki67, ER, and PR. Expression of ER and PR correlated with histological grade. Expression of p53 and Ki67 correlated with clinical stage and histological grade.

CONCLUSIONS

We suggest that class III beta-tubulin plays an important role during the normal biological processes of endometrium. It seems that tubulin has no prognostic value in endometrial carcinoma.

Functional electrical stimulation cycling improves body composition, metabolic and neural factors in persons with spinal cord injury

Persons with spinal cord injury (SCI) are at a heightened risk of developing type II diabetes and cardiovascular disease. The purpose of this investigation was to conduct an analysis of metabolic, body composition, and neurological factors before and after 10 weeks of functional electrical stimulation (FES) cycling in persons with SCI. Eighteen individuals with SCI received FES cycling 2-3 times per week for 10 weeks. Body composition was analyzed by dual X-ray absorptiometry. The American Spinal Injury Association (ASIA) neurological classification of SCI test battery was used to assess motor and sensory function. An oral glucose tolerance (OGTT) and insulin-response test was performed to assess blood glucose control. Additional metabolic variables including plasma cholesterol (total-C, HDL-C, LDL-C), triglyceride, and inflammatory markers (IL-6, TNF-alpha, and CRP) were also measured. Total FES cycling power and work done increased with training. Lean muscle mass also increased, whereas, bone and adipose mass did not change. The ASIA motor and sensory scores for the lower extremity significantly increased with training. Blood glucose and insulin levels were lower following the OGTT after 10 weeks of training. Triglyceride levels did not change following training. However, levels of IL-6, TNF-alpha, and CRP were all significantly reduced.

Two rare cases of methotrexate-induced pneumonitis and pleurisy in patients with gestational trophoblastic neoplasms

BACKGROUND

Pneumonitis is a serious and unpredictable side-effect of treatment with methotrexate (MTX) that may result in a life-threatening outcome. Pulmonary toxicity of methotrexate in patients with a gestational trophoblastic neoplasm (GTN) has rarely been reported before.

CASE REPORTS

For the first time two cases of methotrexate-induced pneumonitis and pleurisy in GTN patients of Chinese ethnicity are presented. Two patients were both categorized as the low-risk group, and underwent a single regimen therapy of methotrexate. Their symptoms, such as fever, chest pain, acute nonproductive cough, dyspnea and hypoxemia did not respond to antibiotics immediately. Treatment with corticosteroids may be helpful.

CONCLUSION

Awareness of pneumonitis and pleurisy, potentially life-threatening complications of MTX, is very necessary and important to early recognition and treatment.

Experimental study on genistein prevention and treatment of transplant arteriosclerosis in aortic transplants of rat

OBJECTIVE

Our objective was to study the effects of genistein, a soy isoflavone, on transplant arteriosclerosis, in addition to its immunosuppressive and antioxidant properties.

MATERIALS AND METHODS

We performed male Brown-Norway to male Lewis aortic transplantation. The recipients were randomly assigned to 3 groups: no treatment controls, dimethyl sulfoxide (DMSO; 5 mL/kg) solvent controls, and experimental group that received genistein (20 mg/kg/d) by daily intraperitoneal injection. On postoperative day 60, the graft was harvested and blood obtained. The transplanted aorta was analyzed by histology and immunohistochemistry. The serum was analyzed by an enzyme-linked immunosorbent assay (ELISA).

RESULTS

Compared with the 2 controls, leukocyte recruitment to the graft was significantly inhibited by genistein, with a profound reduction in the number of CD69 macrophages infiltrating the adventitia of the transplanted aortas. Moreover, genistein significantly inhibited the expression of VEGF and IFN-gamma production (P < .01).

CONCLUSION

These results suggested that the protein tyrosine kinase inhibitor genistein inhibited graft arteriosclerosis.

Administration-route and gender-independent long-term therapeutic correction of phenylketonuria (PKU) in a mouse model by recombinant adeno-associated virus 8 pseudotyped vector-mediated gene transfer

Phenylketonuria (PKU) is an inborn error of metabolism caused by deficiency of the hepatic enzyme phenylalanine hydroxylase (PAH) which leads to high blood phenylalanine (Phe) levels and consequent damage of the developing brain with severe mental retardation if left untreated in early infancy. The current dietary Phe restriction treatment has certain clinical limitations. To explore a long-term nondietary restriction treatment, a somatic gene transfer approach in a PKU mouse model (C57Bl/6-Pahenu2) was employed to examine its preclinical feasibility. A recombinant adeno-associated virus (rAAV) vector containing the murine Pah-cDNA was generated, pseudotyped with capsids from AAV serotype 8, and delivered into the liver of PKU mice via single intraportal or tail vein injections. The blood Phe concentrations decreased to normal levels (< or =100 microM or 1.7 mg/dl) 2 weeks after vector application, independent of the sex of the PKU animals and the route of application. In particular, the therapeutic long-term correction in females was also dramatic, which had previously been shown to be difficult to achieve. Therapeutic ranges of Phe were accompanied by the phenotypic reversion from brown to black hair. In treated mice, PAH enzyme activity in whole liver extracts reversed to normal and neither hepatic toxicity nor immunogenicity was observed. In contrast, a lentiviral vector expressing the murine Pah-cDNA, delivered via intraportal vein injection into PKU mice, did not result in therapeutic levels of blood Phe. This study demonstrates the complete correction of hyperphenylalaninemia in both males and females with a rAAV serotype 8 vector. More importantly, the feasibility of a single intravenous injection may pave the way to develop a clinical gene therapy procedure for PKU patients.

Haploinsufficiency of the mSds3 chromatin regulator promotes chromosomal instability and cancer only upon complete neutralization of p53

The mSin3 corepressor complex has been linked to diverse cancer signaling pathways through its capacity to regulate target gene expression via chromatin modification. mSds3, a cell essential gene, is a key component of the mSin3 complex serving to maintain its inherent histone deacetylase activity. mSds3 also serves an essential role in the establishment of pericentric heterochromatin, and genetic ablation of mSds3 results in chromosome missegregation. In contrast, mSin3A nullizygous cells show normal chromosome dynamics and cytogenetic profiles. The integral role of mSds3 in controlling chromosome segregation and mSin3-regulated transcriptional networks prompted efforts to determine the neoplastic impact of loss of one copy of mSds3 or mSin3A. In particular, we assessed whether loss of one copy of mSds3, alone or in combination with p53 mutation, results in aneuploidy and promotes a cancer-prone condition in the mouse. We observe that, in a p53 null background, loss of one mSds3 allele results in accelerated tumor onset and increased tumor burden. Notably, these mSds3(+/-) p53(-/-) tumors exhibit a more complex cytogenetic profile characterized by marked aneuploidy and centromeric associations. The presence of even one copy of p53 is sufficient to suppress the accelerated tumorigenesis in mSds3(+/-) mice, consistent with a key role for p53 in monitoring mitotic fidelity. These observations with Sds3 mutant mice contrast with mSin3A(+/-) p53(-/-) mice, which do not show an accelerated or increased tumor incidence relative to mSin3A(+/+)p53(-/-) controls, correlating with the absence of aneuploidy detected upon mSin3A genetic inactivation. This genetic study establishes that the capacity of mSds3 to cooperate with p53 deficiency in cancer predisposition relates to its specific role in chromosome segregation, rather than its central role in maintaining a functional mSin3A complex.

Morphological study of the interaction between M21 melanoma and lymphatic endothelium

In order to study the interaction between melanoma and lymphatic endothelial cells (LECs) and to investigate the mechanism of lymphatic metastasis, M21 melanoma cells were seeded on the confluent LECs monolayer and the alterations of both cells were observed. The results showed that tumor cells could both adhere by pseudopodia to LECs at the site near the intercellular junction and on the apical surface. The adhesion of the melanoma cells induced the endothelial junction dissolution and endothelial retraction, which allowed the passage of the tumor cells through the opened gap and attached to the subendothelial matrix, then the tumor cells invaded and migrated under the LECs monolayer. These findings suggest that tumor cells could metastasize through the lymphatic vessel by destroying intercellular junctions or the LECs directly.

Overexpression of sorcin enhances cardiac contractility in vivo and in vitro

Sorcin (SOR), an EF-hand Ca(2+)-binding protein, interacts with the sarcolemmal proteins Annexin VII and L-type Ca(2+)-channel and with the sarcoplasmic reticulum (SR) Ca(2+)-release channel (ryanodine-receptor, RYR), and has been implicated to influence the intracellular Ca(2+)-homeostasis. The present study aimed at investigating the effects of increased SOR expression on force development and relaxation in virus transfected rat hearts and isolated cardiomyocytes. We generated an adenovirus encoding the SOR coding DNA with a separate cassette for green fluorescent protein (GFP) both driven by the CMV-promoter to induce SOR-overexpression (Ad.SOR.GFP). As control served an adenovirus carrying an empty cassette with a separate cassette for GFP also driven by CMV-promoters (Ad.GFP). Cardiomyocytes of healthy male rats were isolated, transfected and cultured for 48 h with Ad.SOR.GFP as well as Ad.GFP as control. In addition, Ad.SOR.GFP was injected into coronary arteries via a catheter-based technique and rat hearts were transfected in vivo for 12 days. Echocardiography was performed to assess cardiac function at 7 and 12 days before the animals were sacrificed. A 1.7-fold increase of the SOR protein amount in cultured myocytes treated with Ad.SOR.GFP compared to Ad.GFP-transfected cells indicated a successful overexpression of SOR. Cell-contracting experiments using infected cardiomyocytes (transfection: 48 h; frequency: 0.5 Hz) exhibited a significantly higher peak force of contraction (FOC) in the SOR-overexpression group (n = 64) vs. control (n = 21) (6.8% +/- 0.2% vs. 4.3% +/- 0.1%). Beta-adrenergic stimulation with forskolin resulted in similar increases in FOC. Echocardiography of in vivo transfected rat hearts exhibited enhanced fractional shortening (65.9 +/- 5.5% vs. 79.3 +/- 2.5%) and decreased end-systolic diameters indicating enhanced cardiac contractility. Gross morphology was similar in both groups after 14 days of transfection. These results strengthen the notion that overexpression of SOR improves cardiac contractility independent of beta-adrenergic stimulation and may prove beneficial in the treatment of decreased cardiac output such as heart failure.

VEGF165 and angiopoietin-1 decreased myocardium infarct size through phosphatidylinositol-3 kinase and Bcl-2 pathways

Angiogenic growth factors, vascular endothelial growth factor (VEGF) and angiopoietin-1 (Ang1) could decrease myocardial infarct size, which was assumed to be related with newly formed capillaries. We doubted that these capillaries could do this solely and the potential protective mechanisms of VEGF and Ang1 on myocardium need to be evaluated. Three types of adenoviruses encoding human VEGF(165) (Ad-VEGF(165)), human angiopoietin-1 (Ad-Ang1) and green fluorescent protein (Ad-GFP, as a parallel control) were constructed. Experiments were taken both in vitro and in vivo. As in vitro, the antiapoptosis effect of VEGF(165), Ang1 and VEGF(165)+Ang1 on cardiac myoblasts was observed, which seemed to be related with the activation of phosphatidylinositol-3 kinase and Bcl-2 pathways. As in vivo, adenoviruses were intramyocardially injected immediately after the ligation of the left anterior descending coronay arteries in rats. The results showed positive effect of VEGF(165), Ang1 and VEGF(165)+Ang1 on decreasing the myocardial infarct size at the 7th day. Myocardial PI-3K activity and Bcl-2 expression were elevated relatively at the 3rd day. The protective effect of VEGF(165) and Ang1 on the myocardium may broaden their functional research and contribute to their clinical use in the future.

A minimally invasive approach for efficient gene delivery to rodent hearts

Transcoronary gene delivery represents a desirable option to achieve global myocardial transgene expression but still requires aggressive surgical preparation in rodents. We therefore developed a catheter-based approach for cardiac gene transfer in the closed chest rat. A double-lumen balloon catheter was used to create aortic occlusion for specific infusion of adenoviral vectors carrying a beta-galactosidase transgene (1 x 10(11) PFU) into the coronaries. Simultaneously, venous return was obstructed by a second balloon catheter in the right atrium. To prolong viral incubation time, we induced a transient cardiac arrest (2 and 5 min) by a combination of acetylcholine and the beta-receptor antagonist, esmolol. At 72 h after transfection, the hearts showed a homogeneous and widespread beta-galactosidase expression, and the transduction efficiency increased and up to about 43% of cardiac myocytes (histochemistry) with a 400-fold increase of beta-galactosidase activity (luminescence assay) compared to sham-operated hearts. Pharmacological treatment aimed at increasing vascular permeability (SNAP and histamine) did not bring about synergistic effects on transfection efficiency. In addition, the method using high intracoronary pressure delivery (>300 mmHg) in a single-pass manner resulted in rather sparse beta-galactosidase expression in the myocardium (3-5% of cardiac myocytes). Therefore, the percutaneous gene delivery system described here provides a simple and minimally invasive procedure that represents a novel strategy for a homogeneous and highly efficient in vivo gene transfer to rodent hearts. Our results also suggest that prolongation of viral incubation time is an effective means for achieving highly efficient myocardial gene transduction.

Raman spectroscopy of selected arsenates--implications for soil remediation

The contamination of soils with heavy metals such as As, Cr and Cu is of great importance; the remediation of such soils even more so. Arsenic compounds are prevalent in soils either through leaching of mine tailings, the use of Cu/Cr/As as a wood preservative or through the use of arsenic in cattle dips. The arsenic compounds in soils and leachates can be highly reactive and mobile, resulting in the formation of metal arsenate compounds. Of these compounds, one such set of minerals that can be formed is the vivianite arsenate minerals. Raman spectroscopy has been used to characterise the vivianite arsenates and to identify arsenic contaminants in a soil.

Coxsackie-and-adenovirus receptor mRNA expression in human heart failure

BACKGROUND

Adenoviral vectors are widely used as gene-transfer vehicles in experimental and clinical studies. Since virus incorporation and transfection efficacy depend to a large extent on the concentration of the coxsackie-and-adenovirus (CAR) receptor on target cells the aim of this study was to quantify the CAR-receptor concentration in various human cardiomyopathies.

METHODS

After RNA isolation from myocardial biopsies obtained during surgical procedures, cDNA was generated by reverse transcription. The relative RNA content was analyzed by quantitative PCR using glyceraldehydes-3-phosphate dehydrogenase (GAPDH) as a standard reference. The cardiomyopathies (CM) analyzed were categorized according to their etiology in dilated CM (DCM, n = 28), ischemic CM (ICM, n = 52), CM in mitral valve disease (MVCM, n = 32) and aortic valve disease (AVCM, n = 32). Data were related to non-cardiomyopathic tissue from donor hearts (non-CM, n = 64).

RESULTS

Compared with non-CM hearts DCM showed a 34-fold (+/-5.4) increase in CAR mRNA concentration, in ICM CAR mRNA was elevated by a factor of 12 (+/-4.3), in MVCM by 27 (+/-7) and AVCM by factor 47 (+/-9.3) (ANOVA p < 0.001). Compared with the expression in rat hearts CAR levels were found to be similar to those in human ICM.

CONCLUSIONS

These results show that cardiomyopathies associated with heart failure transcribe substantially higher levels - on average by a factor of 30 - of CAR-mRNA than non-failing control hearts. Myocardial gene transfer using adenoviral vectors should therefore be facilitated in human cardiomyopathies and may present a promising approach for therapeutic interventions.

Atomic-scale observation of temperature and pressure driven preroughening and roughening

Preroughening and roughening transitions are observed on the GaAs(001) surface using scanning tunneling microscopy. By tuning the substrate temperature or As4 pressure the surface morphology can be made free of islands, covered with one monolayer high islands or covered with islands on top of islands forming a wedding-cake-type structure. These three distinct surface morphologies are classified as ordered flat (OF), disordered flat (DOF), and rough within the restricted solid-on-solid model. Here, the DOF phase is macroscopically flat; however, an up-down-up-down step pattern persists across the entire surface. Using this model we have determined the next-nearest-neighbor interaction energy to be about 0.05 eV.

Molecular assembly in synthesised hydrotalcites of formula Cu(x)Zn(6 - x)Al2(OH)16(CO3) x 4H2O--a vibrational spectroscopic study

Infrared and Raman spectroscopy have been used to characterise synthetic hydrotalcites of formula Cu(x)Zn(6 - x)Al2(OH)16(CO3) x 4H2O. The spectra have been used to assess the molecular assembly of the cations in the hydrotalcite structure. The spectra may be conveniently subdivided into spectral features based (a) upon the carbonate anion (b) the hydroxyl units (c) water units. The Raman spectra of the hydroxyl-stretching region enable bands to be assigned to the CuOH, ZnOH and AlOH units. It is proposed that in the hydrotalcites with minimal cationic replacement that the cations are arranged in a regular array. For the Cu(x)Zn(6 - x)Al2(OH)16(CO3) x 4H2O hydrotalcites, spectroscopic evidence suggests that 'islands' of cations are formed in the structure. In a similar fashion, the bands assigned to the interlayer water suggest that the water molecules are also in a regular well-structured arrangement. Bands are assigned to the hydroxyl stretching vibrations of water. Three types of water are identified (a) water hydrogen bonded to the interlayer carbonate ion (b) water hydrogen bonded to the hydrotalcite hydroxyl surface and (c) interlamellar water. It is proposed that the water is highly structured in the hydrotalcite as it is hydrogen bonded to both the carbonate anion and the hydroxyl surface.

A gene therapy for cancer based on the angiogenesis inhibitor, vasostatin

The growth and persistence of solid tumors and their metastasis are angiogenesis-dependent. Vasostatin, the N-terminal domain of calreticulin inclusive of amino acids 1-180, is a potent angiogenesis inhibitor. To investigate whether intramuscular administration of vasostatin gene has the antitumor activity in mouse tumor models, we constructed a plasmid DNA encoding vasostatin and a control vector. Production and secretion of vasostatin protein by COS cells transfected with the plasmid DNA encoding vasostatin (pSecTag2B-vaso) were confirmed by Western blot analysis and ELISA. Conditioned medium from vasostatin-transfected COS cells apparently inhibited human umbilical vein endothelial cell (HUVEC) and mouse endothelial cell (SVEC4-10) proliferation, compared with conditioned medium from the COS cells transfected with control vector or non-transfected cells. Treatment with pSecTag2B-vaso twice weekly for 4 weeks resulted in the inhibition of tumor growth and the prolongation of the survival of tumor-bearing mice. The sustained high level of vasostatin protein in serum could be identified in ELISA. Angiogenesis was apparently inhibited in tumor by immunohistochemical analysis. Angiogenesis was also inhibited in the chicken embryo CAM assay and mouse corneal micropocket assay. The increased apoptotic cells were found within the tumor tissues from the mice treated with plasmid DNA encoding vasostatin. Taken together, the data in the present study indicate that the cancer gene therapy by the intramuscular delivery of plasmid DNA encoding vasostatin, is effective in the inhibition of the systemic angiogenesis and tumor growth in murine models. The present findings also provide further evidence of the anti-tumor effects of the vasostatin, and may be of importance for the further exploration of the application of this molecule in the treatment of cancer.