Detection of a set of peptide vaccine candidates for use in HLA-A31+ epithelial cancer patients

The molecular basis of host-tumor interaction in HLA-A31+ cancer patients has not been well understood. This lack of clarification is hampering the development of specific immunotherapies for these patients. This study aimed to identify a set of CTL-epitope peptides applicable for the specific immunotherapy of cancer patients with HLA-A31 allele. HLA-A31 allele is expressed in 5-10% of the world population, with the highest expression among Brazilian Amerinds (65%), and the lowest in the Eskimo population (0%). We report herein four cDNAs encoding CTL-epitopes and 7 epitope peptides with the ability to induce HLA-A31-restricted CTLs cytotoxic to tumor cell lines in the peripheral blood mononuclear cells of HLA-A31+ cancer patients. These peptides might be useful for the development of a peptide-based immunotherapy for HLA-A31+ cancer patients.     

Efficacy of combination therapies of percutaneous or laparoscopic ethanol-lipiodol injection and radiofrequency ablation

Percutaneous radiofrequency ablation (RFA) is able to destroy hepatocellular carcinoma (HCC) in a few sessions without major complications. We have previously shown that not only the combined use of percutaneous ethanol injection and RFA (PEI-RFA) but also injection of mixture of ethanol and lipiodol (PELIT) was useful for the treatment of HCC. In the present study, we further developed the combined use of PELIT and RFA through percutaneous or laparoscopic approach (PELI-RFA or LELI-RFA) and evaluated its usefulness. Nineteen nodules in 18 cases were treated with PELI-RFA or LELI-RFA. In the cases treated with LELI-RFA, no bleeding and no spilling milky fluid containing tumor cells were observed from the surface of ablated tumors. In the cases sufficiently treated with PELI-RFA or LELI-RFA, the mixture of ethanol and lipiodol was accumulated in the entire region of the tumor and low-density area was observed around the lipiodol deposit by computed tomography (CT). These delineations of coagulated area were helpful to evaluate the precise area of safety margin around the tumor treated with PELI-RFA or LELI-RFA. Furthermore, the total volume of coagulated necrosis significantly and positively correlated with the product of energy requirement for ablation and the volume of ethanol injected by PELI-RFA or LELI-RFA. Among the cases treated with PELI-RFA or LELI-RFA, local recurrence emerged only in one case in whom enough safety margin could not be achieved by PELI-RFA. Therefore, it is critical to evaluate whether enough safety margin could be obtained with RFA therapy, and PELI-RFA and LELI-RFA are helpful in visualizing the safety margin area.     

Skp2 overexpression is a p27Kip1-independent predictor of poor prognosis in patients with biliary tract cancers

To better understand the pathogenesis of biliary tract carcinoma (BTC) and to increase the accuracy of predicting outcomes for patients with this disease, we performed molecular cytogenetic analyses of BTC cell lines and tumors to identify non-random amplification(s) and target gene(s) within the amplicons. Among several non random chromosomal aberrations detected in BTC cell lines by comparative genomic hybridization, gain/ampli-fication of DNA at 5p was the most frequently observed alteration. We assessed the copy number and expression status of the possible target gene SKP2 for 5p amplification in cell lines and 33 primary stage II or III tumors of BTC. SKP2 was amplified, and subsequently overexpressed in both cell lines and primary tumors of BTC. However, levels of Skp2 and p27Kip1 proteins were not correlated inversely. Heightened expression of Skp2 and reduced expression of p27Kip1 were both associated with a shorter disease-free and/or overall survival in univariate analyses. In multivariate regression analyses, Skp2 and p27Kip1 were independent predictive factors. Those results suggest that (a) overexpression of Skp2 through an amplification mechanism may contribute to the progression of BTC, (b) not only each molecule, but also the combination of Skp2 and p27Kip1, might be a useful predictor of the prognosis of BTC, and (c) molecular targets of Skp2 other than p27Kip1 may also be important factors in the pathogenesis of this disease.     

Defective neocortical development in Fyn-tyrosine-kinase-deficient mice

Fyn tyrosine kinase is involved in the tyrosine-phosphorylation of Disabled-1 in the Reelin signaling pathway, and absence of Fyn is expected to result in a reeler-like phenotype. Thus, this study investigated neocortical development in Fyn-deficient mice. Bromodeoxyuridine labeling revealed the under-migration of later-generated neurons despite the normal placement of earlier-generated neurons. Calbindin- and alpha-calcium/calmodulin-dependent protein kinase II-immunohistochemistry showed that layer II-III neurons were aberrantly stratified, but the neurons in the deeper layers showed little evidence of abnormality. Fyn was intensely expressed in the leading process of migratory cortical neurons generated in the later stage. These findings strongly suggest that Fyn is required for the migration of later-generated neurons, but that it is dispensable for the Reelin-dependent inside-out layer formation.     

Cortical activation in area 3b related to finger movement: an MEG study

To evaluate cortical activation reflecting sensory feedback after finger movement, we recorded movement-related cerebral fields (MRCFs) following voluntary finger movement and somatosensory evoked fields for mixed (median) and pure cutaneous (radial) nerve stimulations (mSEFs and rSEFs) in six normal subjects. Equivalent current dipoles for movement-evoked field 1 (MEF1) in MRCFs and the component (70m) obtained in mSEFs, not clearly in rSEFs, were similarly distributed in each subject. They were located in area 3b, but both mean locations were significantly (p < 0.01) medial to N20m in mSEFs. MEF1 and 70m reflect similar cortical activities related to finger movement and have the same neuronal generator in area 3b, which is different from that of N20m.     

A neuronal mechanism of propofol-induced central respiratory depression in newborn rats

The neural mechanisms of propofol-induced central respiratory depression remain poorly understood. In the present study, we studied these mechanisms and the involvement of gamma-aminobutyric acid (GABA)A receptors in propofol-induced central respiratory depression. The brainstem and the cervical spinal cord of 1- to 4-day-old rats were isolated, and preparations were maintained in vitro with oxygenated artificial cerebrospinal fluid. Rhythmic inspiratory burst activity was recorded from the C4 spinal ventral root. The activity of respiratory neurons in the ventrolateral medulla was recorded using a perforated patch-clamp technique. We found that bath-applied propofol decreased C4 inspiratory burst rate, which could be reversed by the administration of a GABAA antagonist, bicuculline. Propofol caused resting membrane potentials to hyperpolarize and suppressed the firing of action potentials in preinspiratory and expiratory neurons. In contrast, propofol had little effect on resting membrane potentials and action potential firing in inspiratory neurons. Our findings suggest that the depressive effects of propofol are, at least in part, mediated by the agonistic action of propofol on GABAA receptors. It is likely that the GABAA receptor-mediated hyperpolarization of preinspiratory neurons serves as the neuronal basis of propofol-induced respiratory depression in the newborn rat.     

Trials of regeneration and gene therapies in endocrine organs,especially in adrenal glands

Recent progress in trials of regeneration and gene therapy in endocrine organs, especially in adrenal glands has been reviewed. Gene therapies using adenovirus have been most frequently tested in vivo and in vitro, aiming at improvement of steroidogenesis and suppression of adrenal tumor growth. Although the effects were temporal, promising results have been obtained. Interestingly, adrenocortical tissue was shown to be formed by transplantation of adrenocortical cells and to replace the adrenal functions of adrenalectomized animals. Engineered ES cells stably expressing Ad4BP/SF-1 were shown to be directed toward steroidogenic lineage, suggesting a future possibility of regeneration of adrenal cells.     

Membrane-anchored heparin-binding EGF-like growth factor processing by ADAM12 in cardiac hypertrophy

G-protein coupled receptor(GPCR) agonists are well-known inducers of cardiac hypertrophy. We found that the shedding of HB-EGF via metalloproteinase activation and subsequent transactivation of the epidermal growth factor receptor occurred when cardiomyocytes were stimulated by GPCR agonists, leading to cardiac hypertrophy. A new inhibitor of HB-EGF shedding, KB-R7785, blocked this signaling. We cloned a disintegrin and metalloprotease 12(ADAM12) as a specific enzyme to shed HB-EGF in the heart and found that dominant negative expression of ADAM12 abrogated this signaling. KB-R7785 bound directly to ADAM12, suggesting that inhibition of ADAM12 blocked the shedding of HB-EGF. In mice with cardiac hypertrophy, KB-R7785 inhibited the shedding of HB-EGF and attenuated hypertrophic changes. These data suggest that shedding of HB-EGF by ADAM12 plays an important role in cardiac hypertrophy, and that inhibition of HB-EGF shedding could be a potent therapeutic strategy for cardiac hypertrophy.