Regulation of aminopeptidase A expression in cervical carcinoma: role of tumor-stromal interaction and vascular endothelial growth factor

We previously demonstrated that aminopeptidase A (APA), a membrane-bound metallopeptidase degrading bioactive peptides such as angiotensin II (Ang II), is expressed in neoplastic lesions of the uterine cervix, and that its expression is upregulated as the lesion progresses from cervical intraepithelial neoplasms (CIN) toward invasive squamous cell carcinomas (SCC). The present study investigated the regulatory mechanisms involved in APA expression and its potential role in cervical carcinoma. Immunohistochemical staining in high-grade CIN and SCC tissues showed that APA was strongly expressed at the edge of lesions adjacent to cervical stromal cells. Fluorescence-activated cell sorting analysis demonstrated that cell surface APA expression was extremely low in three human SCC cell lines, SiHa, TCS and CaSki, under basal conditions. However, both contact and noncontact cocultures with human cervical fibroblasts resulted in the induction of APA expression in these SCC cells. APA expression was also induced in vivo when TCS cells were subcutaneously inoculated into nude mice. Furthermore, APA expression and enzymatic activity were enhanced by addition of the conditioned medium (CM) from fibroblast culture, but not by heat-treated CM. Among the various cytokines tested, vascular endothelial growth factor (VEGF) significantly increased APA activity, and induction of APA by the fibroblast CM was partly inhibited by anti-VEGF neutralizing antibody. Finally, APA cDNA-transfected APA-overexpressing TCS cells significantly reduced the Ang II-induced cell invasion ability as compared with parental or control vector-transfected TCS cells, although there was no significant difference in cellular proliferation among them. These results suggested the importance of tumor-stromal interaction for the regulation of APA expression in the microenvironment of cervical carcinoma and the potential role for this peptidase in regulating tumor invasion through inactivation of Ang II activity.     

Magnetic resonance angiographic localization of the artery of Adamkiewicz for spinal cord blood supply

Background

The purpose of this study was to determine whether the artery of Adamkiewicz (ARM) can be detected by magnetic resonance angiography and to determine the usefulness of preoperative magnetic resonance angiography evaluation of the ARM.

Methods

Between April 2000 and December 2003, 120 patients underwent magnetic resonance angiography for detection of the ARM. The morphology of the anterior spinal artery at the ARM junction, as revealed by magnetic resonance angiography, in 99 patients in whom ARM was preoperatively detected was classified into the following three types: noncontinuation of the anterior spinal artery above the ARM junction (type A), continuation of the anterior spinal artery above and below the ARM junction (type B), and noncontinuation of the anterior spinal artery below the ARM junction (type C).

Results

The ARMs were detected in 99 (83%) of 120 patients, and from a total of 110 ARMs 105 (95%) originated from intercostal arteries branching from the left side and 94 (86%) originated between Th9 and Th11. Two ARMs were found in 11 (11%) of 99 patients in whom ARMs were detected. In 107 patients, who underwent magnetic resonance angiography to reveal the morphology of the anterior spinal artery at the ARM junction, the patterns of the anterior spinal artery were type A in 59 patients (55%), type B in 21 patients (20%), type C in 3 patients (3%) and not classified in 24 patients (22%). No spinal cord injury occurred in patients in whom the ARM had been preoperatively detected.

Conclusions

Preoperative detection of the ARM is possible by magnetic resonance angiography and is very useful for reducing the incidence of ischemic injury of the spinal cord.     

Immunolocalization of vascular endothelial growth factor during heterotopic bone formation induced from grafted periosteum

Vessel invasion is an important step in cartilage replacement that leads to bone formation, and vascular endothelial growth factor (VEGF) has been implicated as a key player in this process. Although grafted periosteum undergoes endochondral ossification, little is known about the role of VEGF in this process. In the current study the authors investigated by immunohistochemical, histochemical, and ultrastructural techniques the localization of VEGF during bone formation in periosteal grafts. At day 14 after grafting the tibias of Japanese white rabbits, periosteal cells in the grafted tissue had differentiated into chondrocytes to form cartilage. Some chondrocytes were immunopositive for VEGF expression, and subsequent vessel invasion occurred predominantly in these VEGF-positive areas. At day 45, the cartilage invaded by blood vessels had been replaced by newly formed bone. These findings suggest that VEGF is associated with the process of blood vessel invasion into cartilage before bone replacement in endochondral ossification from grafted periosteum.     

Quantitative analysis of adenosine A1 receptors in human brain using positron emission tomography and [1-methyl-11C]8-dicyclopropylmethyl-1-methyl-3-propylxanthine

Fully quantitative analysis of the adenosine A₁ receptor (A1R) in the brain with ¹¹C-MPDX and positron emission tomography is reported. The kinetics is described using a two-tissue three-compartment model, and estimated binding potentials correspond well with the estimates made by Logan plot. The image of the binding potential of the MPDX is physiologically reasonable. We conclude that MPDX is applicable to the visualization of the A1Rs in the brain with Logan plot.     

Analysis of human locomotion by recording sole-floor reaction forces from anatomically discrete points

Sole-floor reaction forces were recorded from five anatomically discrete points to analyze characteristics of human locomotion. Strain gauge of 14 mm diameter were firmly attached to the sole of bare-foot for recording force changes from the following five points: (1) medial process of calcaneus, (2) head of 1st metatarsal, (3) head of 3rd metatarsal, (4) head of 5th metatarsal and (5) great toe. Fifteen healthy adults were asked to walk at 2, 4, 6 and 8 km/h and to run at 8 km/h on the treadmill. Sole-floor reaction forces from 1st to 5th metatarsals show reciprocal changes during stance phase, while force from 1st metatarsal is strong 5th metatarsal shows weak reaction and vice versa. This phenomenon may be an expression of locomotor program to maintain vertical stability of the body during stance phase. There was a linear relation between walking speeds and sum of force from the five points, although sum of forces from three metatarsals did not change significantly during the walking speeds, indicating mainly calcaneus and great toe contribute to increasing walking speed. During running the sum of force from the three metatarsals increased sharply, joining the other two points to increase thrust.     

Causes for the large genome size in a cyanobacterium Anabaena sp. PCC7120

Three possible causes responsible for the large genome size of a cyanobacterium Anabaena sp. PCC7120 are investigated: 1) sequential tandem duplications of gene segments, genes or genomic segments, 2) horizontal gene transfers from other organisms, and 3) whole-genome duplication. We evaluated the frequency distribution of angles between paralog locations for the possibility 1), the fraction of genes deviated in GC content, GC skew, AT skew and codon adaptation index for the 2) and the gene-configuration comparison of paralogs for the 3). As a result, the possibility 3), the whole-genome duplication, was more reasonable as a molecular cause than the other causes for the large genome size in Anabaena sp. PCC7120. In addition, the whole-genome duplication was supported by the analysis of distribution pattern of protein genes with respect to functional categories.     

Identification of differentially expressed genes in salivary gland tumors with cDNA microarray

OBJECTIVE: The final goal of this study is to develop a pre-operative fine needle aspiration biopsy (FNA) diagnostic system based on gene expression profiles. As the first step to that end, the present study was performed to determine whether the cDNA microarray system is applicable for histological evaluation of parotid gland tumors. METHODS: We investigated molecular characteristics on the basis of gene expression patterns of the two most common types of salivary gland tumors (pleomorphic adenomas and Warthin tumors) and normal salivary gland tissues, using the cDNA microarray system. RESULTS: Pleomorphic adenomas and Warthin tumors can be classified by cDNA microarray. In pleomorphic adenomas, 11 independent genes were found to be up-regulated and 2 genes were down-regulated. In Warthin tumors, five independent genes were found to be up-regulated, and six genes were down-regulated. In hierarchical clustering analysis, cases were further grouped into two clusters according to the histological type. Furthermore, cDNA microarray enabled pleomorphic adenomas to be subclassified into three clusters according to the histological subtypes. CONCLUSIONS: This study suggested that cDNA microarray may be useful and applicable for the pre-operative diagnosis (such as FNA) of the salivary gland tumor.     

Histopathological features of nasal polyps with asthma association: an immunohistochemical study

BACKGROUND: Myofibroblasts are related to airway remodeling and may play an important role in the pathogenesis of the histological features of nasal polyps associated with asthma. The aim of this study was to analyze and compare the eosinophilic cationic protein, transforming growth factor (TGF) beta, and myofibroblasts in the nasal polyps of patients with chronic sinusitis associated with and without asthma. METHODS: Nasal polyp samples were obtained during endoscopic sinus surgery and were classified into asthma and nonasthma groups. Immunohistochemistry was performed using antibodies against activated eosinophils, TGF-beta, and myofibroblasts. RESULTS: The asthma group showed an increased number of activated eosinophils, TGF-beta, and myofibroblasts compared with the nonasthma and control groups. We found no correlation of asthma and aspirin intolerance with the immunohistochemical findings. CONCLUSION: The increased number of myofibroblasts in the nasal polyps of the asthma group may be responsible for the extracellular matrix accumulation, polyp formation, and polyp recurrence.     

Bisphosphonate incadronate prevents total gastrectomy-induced osteopenia in rats

Purpose. Total gastrectomy (GX) leads to osteopenia. We examined the effects of bisphosphonate incadronate (INC), a potent inhibitor of bone resorption, on bone characteristics in rats that underwent total GX. Experimental design. Male Wistar rats were divided into four groups: (1) sham-operation (n = 10); (2) total GX control (n = 6); (3) total GX with 0.3 mg kg⁻¹ day⁻¹ oral administration of INC (n = 7); and (4) total GX with 3.0 mg kg⁻¹ day⁻¹ oral administration of INC (n = 7). Results. Total GX significantly impaired bone mineral density; these effects were prevented by treatment with INC. Similarly, in GX control rats, morphometrical changes of femoral metaphysis stained with Villanueva's and Villanueva-Goldner's: bone volume, tissue volume, mineral apposition rate, labeled/bone surface, bone formation rate, osteoid volume, mineralization lag time as well as serum osteocalcin, and urinary deoxypyridinoline demonstrated simultaneous existence of both osteomalacia and osteopenia; these impairments were also prevented by INC. However, GX-induced decrease in serum levels of calcium as well as 25-hydroxyvitamin D/24,25-dihydroxyvitamin D and the increase in 1,25-dihydroxyvitamin D were not prevented by administration of INC. Conclusions. These results enhance the understanding of the unique pathophysiology of both osteomalacia and osteoporosis induced by total GX and suggest the possibility of using INC as preventive therapy for osteopenia in GX-treated patients.