Overproduction of Th2-specific chemokines in NC/Nga mice exhibiting atopic dermatitis-like lesions

We have examined the expression of chemokines and their receptors in the atopic dermatitis-like (AD-like) lesions of NC/Nga mice. Such lesions develop when the mice are kept in conventional conditions, but not when they are kept isolated from specific pathogens. The thymus- and activation-regulated chemokine TARC is unexpectedly highly expressed in the basal epidermis of 14-week-old mice with lesions, whereas it is not expressed in the skin without lesions. Production of TARC by keratinocytes was confirmed by culturing murine keratinocytic cell line cells (PAM212) with TNF-alpha, IFN-gamma, or IL-1beta. Expression of another Th2 chemokine, macrophage-derived chemokine (MDC), was observed in the skin from mice kept in both conventional and pathogen-free conditions, but expression of MDC was increased severalfold in the skin with lesions. The cellular origin of MDC was identified to be dermal dendritic cells. Infiltration of the skin by IL-4-producing T cells and mast cells, and the increase of CCR4 mRNA in the skin, coincided with the development of AD lesions. These observations indicate that TARC and MDC actively participate in the pathogenesis of AD-like lesions in NC/Nga mice and that these Th2 chemokines could be novel targets for intervention therapy of AD in humans.

Double-phase helical CT of small renal parenchymal neoplasms: correlation with pathologic findings and tumor angiogenesis

PURPOSE

To correlate the enhancement pattern of double-phase helical computed tomography (CT) of small renal parenchymal neoplasms with pathologic findings and tumor angiogenesis, and evaluate whether the enhancement pattern would be useful in differentiating the histomorphologic types of small renal parenchymal neoplasms.

MATERIALS AND METHODS

Double-phase helical CT (5 mm slice) of the corticomedullary phase (CMP) and late nephrographic phase (NP) was performed in 40 surgically resected renal neoplasms <3.5 cm. The patterns of CT attenuation value and homogeneity were correlated with the subtypes of neoplasms, microvessel density, and the existence of intratumoral necrosis or hemorrhage.

RESULTS

Clear cell renal cell carcinomas (RCC) (n = 29) showed a peak attenuation value in the CMP of >100 HU [Hounsfield units]. Chromophobe cell RCC (n = 2) showed a peak attenuation value in the CMP of <100 HU. Papillary RCC (n = 5) showed a gradual enhancement with the attenuation value in the CMP of <100 HU. However oncocytomas (n = 2) and metanephric adenomas (n = 2) also showed patterns similar to these subtypes of RCC. The degree of enhancement in the CMP correlated with microvessel density (r = 0.87). All tumors with an homogeneous enhancement pattern did not show necrosis or hemorrhage on histologic specimen.

CONCLUSION

The enhancement pattern in double-phase helical CT was different among the subtypes of RCC, and correlated with microvessel density or the existence of intratumoral necrosis or hemorrhage. However it did not differentiate between RCC and other solid tumors.

Active participation of CCR5(+)CD8(+) T lymphocytes in the pathogenesis of liver injury in graft-versus-host disease

We examined the molecular pathogenesis of graft-versus-host disease-associated (GVHD-associated) liver injury in mice, focusing on the role of chemokines. At the second week after cell transfer in the parent-into-F1 model of GVHD, CD8(+) T cells -- especially donor-derived CD8(+) T cells -- infiltrated the liver, causing both portal hepatitis and nonsuppurative destructive cholangitis (NSDC). These migrating cells expressed CCR5. Moreover, macrophage inflammatory protein-1alpha (MIP-1alpha), one of the ligands for CCR5, was selectively expressed on intralobular bile duct epithelial cells, endothelial cells, and infiltrating macrophages and lymphocytes. Administration of anti-CCR5 antibody dramatically reduced the infiltration of CCR5(+)CD8(+) T lymphocytes into the liver, and consequently protected against liver damage in GVHD. The levels of Fas ligand (FasL) mRNA expression in the liver were also decreased by anti-CCR5 antibody treatment. Anti-MIP-1alpha antibody treatment also reduced liver injury. These results suggest that MIP-1alpha-induced migration of CCR5-expressing CD8(+) T cells into the portal areas of the liver plays a significant role in causing liver injury in GVHD; thus, CCR5 and its ligand may be the novel target molecules of therapeutic intervention of hepatic GVHD.

Angiomyolipoma: imaging findings in lesions with minimal fat

PURPOSE

To investigate a method of diagnosing angiomyolipoma that contains minimal fat.

MATERIALS AND METHODS

In six cases of angiomyolipoma with minimal fat, the attenuation on contrast material-enhanced and unenhanced computed tomographic (CT) images, the echogenicity on sonograms, the signal intensity on T2-weighted magnetic resonance (MR) images, and the gross configuration of the lesion were retrospectively analyzed. In 100 cases of renal cell carcinoma, the same parameters were analyzed, and results were compared with those of angiomyolipoma.

RESULTS

When compared with the surrounding renal parenchyma, all six angiomyolipomas showed homogeneously high attenuation on unenhanced CT images, homogeneous enhancement on contrast-enhanced CT images, and homogeneous isoechogenicity on sonograms. Of the five angiomyolipomas examined with MR imaging, four were hypointense and one was isointense on T2-weighted images. All six angiomyolipomas protruded from the renal margin. None of the 100 renal cell carcinomas showed homogeneously high attenuation on unenhanced CT images, homogeneous enhancement on contrast-enhanced CT images, or homogeneous isoechogenicity on sonograms.

CONCLUSION

In the kidney, homogeneously high attenuation on unenhanced CT images, homogeneous enhancement on contrast-enhanced CT images, and homogeneous isoechogenicity on sonograms are suggestive of angiomyolipoma that contains abundant muscle and minimal fat.

Role of reactive oxygen species in cis-dichlorodiammineplatinum-induced cytotoxicity on bladder cancer cells

This study was undertaken to investigate the intracellular induction of reactive oxygen species (ROS) by cis-dichlorodiammineplatinum (CDDP) and the augmentation of their cytotoxicity in bladder cancer cells (KU7) by enhancement of ROS generation by the glutathione (GSH) depletors buthionine sulphoximine (BSO) and diethylmaleate (DEM). CDDP-induced cytotoxicity in KU7 cells and its modulation by GSH depletors were determined using spectrophotometric measurement with crystal violet staining. The effects of GSH depletors on intracellular GSH levels were confirmed using the GSH reductase-DTNB recycling method. Intracellular ROS generation induced by CDDP with or without GSH depletors was estimated from the amount of intracellular dichlorofluorescein (DCF), an oxidized product of dichlorofluorescein (DCFH), which was measured with an anchored cell analysis and sorting system. The cytotoxic effects of CDDP (IC50 15.0 +/- 2.5 microM) were significantly enhanced by BSO (IC50 9.3 +/- 2.6 microM, P < 0.01) and DEM (IC50 10.3 +/- 0.3 microM, P <0.01). BSO and DEM produced a significant depletion in intracellular GSH levels (9.6 +/- 0.4 nmol 10(-6) cells, 17.9 +/- 1.0 nmol 10(-6) cells) compared with the controls (30.5 +/- 0.6 nmol 10(-6) cells). Intracellular DCF production in KU7 cells treated with CDDP (1.35 +/- 0.33 microM) was significantly enhanced by the addition of BSO (4.43 +/- 0.33 microM) or DEM (3.12 +/- 0.22 microM) at 150 min. These results suggest that ROS may play a substantial role in CDDP-induced cytotoxicity and that GSH depletors augment its cytotoxicity through an enhancement of ROS generation in bladder cancer cells.

Cloning, functional expression and tissue distribution of human cDNA for the alpha 1C-adrenergic receptor

We have cloned human alpha 1C-adrenergic receptor from human prostate cDNA library. The deduced amino acid sequence of the clone (P2C4) encodes a protein of 466 amino acids that showed strong sequence homology to the previously cloned bovine alpha 1C-adrenergic receptor. The radioligand binding properties of P2C4 expressed in COS-7 cells were very similar to those of bovine alpha 1C-adrenergic receptor. With reverse-transcription polymerase chain reaction assay, we observed alpha 1C-adrenergic receptor transcripts in heart, brain, liver and prostate, but not in kidney, lung, adrenal, aorta and pituitary. The data show that the clone P2C4 encodes a human alpha 1C-adrenergic receptor cDNA, and the receptor subtype is expressed not widely but localized in several human tissues.

Quantification and distribution of alpha 1-adrenoceptor subtype mRNAs in human prostate: comparison of benign hypertrophied tissue and non-hypertrophied tissue

1. There are at least three alpha 1-adrenoceptor subtypes, alpha 1a, alpha 1b and alpha 1d, in human tissues. Using an RNase protection assay, we have now determined the amount of each subtype mRNA in human prostatic tissue, for both benign prostatic hypertrophy (BPH) and non-BPH. In all tissue samples examined, the predominant subtype mRNA was alpha 1a. The total abundance of alpha 1-adrenoceptor mRNA in BPH samples was over six times that in non-BPH samples. This increase was mostly accounted for by alpha 1a, which was almost nine times as abundant in BPH samples as in non-BPH samples. The abundance of alpha 1b was almost the same between BPH and non-BPH samples, and the abundance of alpha 1d in BPH samples was about three times that in non-BPH samples. The ratio of the numbers of the subtype mRNAs, alpha 1a: alpha 1b: alpha 1d, was 85:1:14 in BPH samples and 63:6:31 in non-BPH samples. 2. In situ hybridization studies showed no significant differences in the tissue localization of alpha 1-adrenoceptor subtype mRNAs between BPH and non-BPH samples. alpha 1a and alpha 1d were clearly detected in the interstitium of the prostate, where alpha 1a was stained more intensely than alpha 1d, and the positive sites were primarily smooth muscle cells. In contrast, alpha 1b staining was very faint. 3. This increase in mRNA abundance may be directly related to the contraction of prostatic tissue that leads to obstruction of the urinary tract in BPH patients. Specifically, our data suggest that increased expression of the alpha 1a subtype may be primarily responsible for the contraction of the prostate.

Identification of receptors of main sex-pheromone components of three Lepidopteran species

Male moths discriminate conspecific female-emitted sex pheromones. Although the chemical components of sex pheromones have been identified in more than 500 moth species, only three components in Bombyx mori and Heliothis virescens have had their receptors identified. Here we report the identification of receptors for the main sex-pheromone components in three moth species, Plutella xylostella, Mythimna separata and Diaphania indica. We cloned putative sex-pheromone receptor genes PxOR1, MsOR1 and DiOR1 from P. xylostella, M. separata and D. indica, respectively. Each of the three genes was exclusively expressed with an Or83b orthologous gene in male olfactory receptor neurons (ORNs) that are surrounded by supporting cells expressing pheromone-binding-protein (PBP) genes. By two-electrode voltage-clamp recording, we tested the ligand specificity of Xenopus oocytes co-expressing PxOR1, MsOR1 or DiOR1 with an OR83b family protein. Among the seven sex-pheromone components of the three moth species, the oocytes dose-dependently responded only to the main sex-pheromone component of the corresponding moth species. In our study, PBPs were not essential for ligand specificity of the receptors. On the phylogenetic tree of insect olfactory receptors, the six sex-pheromone receptors identified in the present and previous studies are grouped in the same subfamily but have no relation with the taxonomy of moths. It is most likely that sex-pheromone receptors have randomly evolved from ancestral sex-pheromone receptors before the speciation of moths and that their ligand specificity was modified by mutations of local amino acid sequences after speciation.

Constitutive activation of nuclear factor-kappaB prevents TRAIL-induced apoptosis in renal cancer cells

TRAIL has gained much attention for its specific induction of apoptosis in cancer cells but not in normal cells. This phenomenon has been explained thus: that cancer cells dominantly express death receptors while normal cells express decoy receptors. However, recent reports have shown that some cancer cell lines are resistant to TRAIL-induced apoptosis despite the absence of decoy receptors and the presence of death receptors. This suggested the existance of an inhibitory factor. We herein showed that NF-kappaB is a key molecule underlying the TRAIL-resistant mechanism in renal cell carcinoma (RCC) cell lines. We observed that NF-kappaB is constitutively activated in resistant cell lines. Forced expression of antisense cDNA of IkappaBalpha, a specific inhibitor of NF-kappaB, in TRAIL-sensitive cell lines with a low NF-kappaB activity result in constitutive activation of NF-kappaB and resistance to TRAIL-induced apoptosis. Adenoviral expression of a stable form of IkappaBalpha in the TRAIL-resistant cell lines induced apoptosis. These data suggest that RCC can be classified into two subsets: TRAIL-sensitive RCC with a low NF-kappaB activity and TRAIL-resistant RCC with constitutively activated NF-kappaB. In the former group TRAIL can be a treatment option, while in the latter group a molecular approach targeting NF-kappaB appears to be a promising therapy.

Pharmacological profile of a high affinity dipeptide NK1 receptor antagonist, FK888

1. In our search for compounds that inhibit the binding of [3H]-substance P (SP) to guinea-pig lung membranes, the dipeptide SP antagonist, FK888, was developed by chemical modification of the parent compound, (D-Pro4, D-Trp7,9,10, Phe11)SP4-11. 2. In a [3H]-SP binding assay using guinea-pig lung membranes and rat brain cortical synaptic membranes, FK888 displaced [3H]-SP binding with a Ki value of 0.69 +/- 0.13 nM and 0.45 +/- 0.17 microM, respectively, in a competitive manner. 3. FK888 inhibited the contraction of guinea-pig isolated ileum induced by SP in the presence of atropine and indomethacin (a NK1 receptor bioassay) with a pA2 value of 9.29 (8.60-9.98). 4. FK888 inhibited contractions of rat vas deferens by NKA (a NK2 receptor bioassay) and of rat portal vein by NKB (a NK3 receptor bioassay) at concentrations at least 10,000 times greater than that required to inhibit contractions of guinea-pig ileum. 5. FK888 also inhibited SP-induced airway oedema in guinea-pig after both intravenous and oral administration. 6. These data demonstrate that FK888 is a potent and selective NK1 antagonist which is active both in vitro and in vivo.

Pivotal role of TARC, a CC chemokine, in bacteria-induced fulminant hepatic failure in mice

Thymus and activation-regulated chemokine (TARC) is a recently identified lymphocyte-directed CC chemokine which specifically chemoattracts T helper type 2 CD4(+) T cells in human. To establish the pathophysiological roles of TARC in vivo, we investigated whether a monoclonal antibody (mAb) against TARC could inhibit the induction of hepatic lesions in murine model using Propionibacterium acnes and lipopolysaccharide (LPS). P. acnes-induced intrahepatic granuloma formation in the priming phase is essential to the subsequent liver injury elicited by a low dose of LPS. The priming phase appears to be dominated by Th1 type immune responses determined by the profile of chemokine and chemokine receptor expression. TARC was selectively produced by granuloma-forming cells, and CC chemokine receptor 4 (CCR4)-expressing CD4(+) T cells migrated into the liver after LPS administration. In vivo injection of anti-TARC mAb just before LPS administration protected the mice from acute lethal liver damage, which was accompanied by a significant reduction of both CCR4 mRNA expression and IL-4 production by liver-infiltrating CD4(+) T cells. Moreover, both TNF-alpha and Fas ligand expressions in the liver were decreased by anti-TARC treatment. These results suggest that recruitment of IL-4-producing CCR4(+) CD4(+) T cells by granuloma-derived TARC into the liver parenchyma may be a key cause of massive liver injury after systemic LPS administration.

Age-related prevalence of erectile dysfunction in Japan: assessment by the International Index of Erectile Function

BACKGROUND

The effects of age and concomitant chronic illness on male sexual function were investigated to obtain insight into the prevention of erectile dysfunction (ED).

METHODS

A questionnaire from the International Index of Erectile Function (IIEF) was given to 2311 non-institutionalized men aged 23-79 years along with a survey of health status. The study sample consisted of 1517 men who provided complete responses to the questionnaire. For statistical analysis, ANOVA was conducted to evaluate the effect of aging on the sexual functions and a logistic regression model was used to identify significant independent risk factors for ED.

RESULTS

There was a significant correlation between age and the scores for erectile function, orgasmic function, sexual desire and intercourse satisfaction. The prevalence of moderate and severe cases of ED were 1.8% and 0% for ages 23-29; 2.6% and 0% for ages 30-39; 7.6% and 1.0% for ages 40-49; 14.0% and 6.0% for ages 50-59; 25.9% and 15.9% for ages 60-69; and 27.9% and 36.4% for ages 70-79 years, respectively. Hypertension, diabetes mellitus, heart disease, chronic hepatitis, disc herniation and cerebral infarction under treatment with anticoagulants were significant independent risk factors for ED.

CONCLUSIONS

The results obtained indicated a significant association between aging and chronic diseases and erectile function. Further epidemiologic research and analysis of individual risk factors are required to allow more effective future strategies for the treatment and prevention of ED.

Role of nitric oxide and cyclic GMP in the dizocilpine-induced impairment of spontaneous alternation behavior in mice

The activation of N-methyl-D-aspartate receptors induces the synthesis of nitric oxide, which activates soluble guanylate cyclase and leads to the formation of cyclic GMP in the brain. The inhibition of nitric oxide production, as well as the blockade of N-methyl-D-aspartate receptors, has been reported to prevent the induction of hippocampal long-term potentiation and learning and memory formation in vivo, although the effects of inhibitors of nitric oxide synthase are still controversial. We investigated the putative role of nitric oxide and cyclic GMP in dizocilpine-induced memory impairment in mice. The nitric oxide synthase inhibitors, NG-nitro-L-arginine methyl ester and 7-nitro indazole, as well as dizocilpine, a non-competitive N-methyl-D-aspartate receptor antagonist, dose-dependently impaired spatial working memory in mice, assessed by their spontaneous alternation behavior in a Y-maze. The inhibitory effects of both NG-nitro-L-arginine methyl ester and dizocilpine on their behavior were completely reversed by 8-bromo-cyclic GMP. Cyclic GMP levels in the cerebellum were reduced by treatment with dizocilpine. NG-Nitro-L-arginine methyl ester and 7-nitro indazole reduced cyclic GMP levels in the cerebral cortex/hippocampus and cerebellum, and the suppressive effect of NG-nitro-L-arginine methyl ester on cyclic GMP levels in the cerebral cortex/hippocampus was reversed by co-treatment with L-arginine. Cyclic AMP levels in the brain were not affected by treatment with either dizocilpine, NG-nitro-L-arginine methyl ester, or 7-nitro indazole. Neither NG-nitro-L-arginine methyl ester nor L-arginine had any effect on monoamine and acetylcholine metabolism in the brain. These results suggest that the reduction in nitric oxide/cyclic GMP production in the brain may be responsible for dizocilpine-induced impairment of spontaneous alternation behavior in a Y-maze.

Early postnatal ataxia and abnormal cerebellar development in mice lacking Xeroderma pigmentosum Group A and Cockayne syndrome Group B DNA repair genes

Xeroderma pigmentosum (XP) and Cockayne syndrome (CS) are rare autosomal recessive disorders associated with a defect in the nucleotide excision repair (NER) pathway required for the removal of DNA damage induced by UV light and distorting chemical adducts. Although progressive neurological dysfunction is one of the hallmarks of CS and of some groups of XP patients, the causative mechanisms are largely unknown. Here we show that mice lacking both the XPA (XP-group A) and CSB (CS-group B) genes in contrast to the single mutants display severe growth retardation, ataxia, and motor dysfunction during early postnatal development. Their cerebella are hypoplastic and showed impaired foliation and stunted Purkinje cell dendrites. Reduced neurogenesis and increased apoptotic cell death occur in the cerebellar external granular layer. These findings suggest that XPA and CSB have additive roles in the mouse nervous system and support a crucial role for these genes in normal brain development.

Small solid renal lesions: usefulness of power Doppler US

PURPOSE

To evaluate whether the vascular pattern at power Doppler ultrasonography (US) improves diagnostic accuracy in small solid renal lesions over that at gray-scale US.

MATERIALS AND METHODS

Gray-scale and power Doppler US were performed prospectively in 64 small (1.5-3.0-cm-diameter) solid renal lesions (26 renal cell carcinomas [RCCs], 34 angiomyolipomas, two oncocytomas, two pseudotumors). At gray-scale US, echogenicity and homogeneity of the lesion, an anechoic rim, intratumoral cysts, shadowing, or a central scar were sought. At power Doppler US, the vascular distribution was divided into four patterns.

RESULTS

Findings at gray-scale US included an anechoic rim or intratumoral cysts in 20 of 26 RCCs (77%) and the two oncocytomas. Shadowing was seen in seven of 34 angiomyolipomas (21%). Echogenicity, homogeneity, and a central scar were not pathognomonic. At power Doppler US, pattern 3 (peripheral) or 4 (mixed penetrating and peripheral) was seen in all RCCs, seven of 34 angiomyolipomas, and the two oncocytomas. Pattern 1 (intratumoral focal) or 2 (penetrating) was seen in 27 angiomyolipomas. Pattern 1 or 2 was characteristic of angiomyolipoma. The rate of correct diagnosis was significantly increased with combined US (78%) as compared to that with gray-scale (42%) or power Doppler (45%) US alone.

CONCLUSION

The vascular distribution at power Doppler US could add important information to gray-scale US findings for differential diagnosis of small solid renal lesions.

Aberrant DNA methylation associated with silencing BNIP3 gene expression in haematopoietic tumours

Hypoxia is a key factor contributing to the progression of human neoplasias and to the development of resistance to chemotherapy. BNIP3 is a proapoptotic member of the Bcl-2 protein family involved in hypoxia-induced cell death. We evaluated the expression and methylation status of BNIP3 gene to better understand the role of epigenetic alteration of its expression in haematopoietic tumours. Methylation of the region around the BNIP3 transcription start site was detected in four acute lymphocytic leukaemia, one multiple myeloma and one Burkitt lymphoma cell lines, and was closely associated with silencing the gene. That expression of BNIP3 was restored by treatment with 5-aza2′-deoxycytidine (5-aza-dC), a methyltransferase inhibitor, which confirmed the gene to be epigenetically inactivated by methylation. Notably, re-expression of BNIP3 using 5-aza2-dC also restored hypoxia-mediated cell death in methylated cell lines. Acetylation of histone H3 in the 5′ region of the gene, which was assessed using chromatin immunoprecipitation assays, correlated directly with gene expression and inversely with DNA methylation. Among primary tumours, methylation of BNIP3 was detected in five of 34 (15%) acute lymphocytic leukaemias, six of 35 (17%) acute myelogenous leukaemias and three of 14 (21%) multiple myelomas. These results suggest that aberrant DNA methylation of the 5′ CpG island and histone deacetylation play key roles in silencing BNIP3 expression in haematopoietic tumours.

Inhibition of Wnt signaling downregulates Akt activity and induces chemosensitivity in PTEN-mutated prostate cancer cells

BACKGROUND

The cross-talk between Wnt signaling and the Akt pathway in prostate cancer (Pca) is still unclear. In the present study, we found that WIF-1 downregulates the Akt pathway and also enhances chemosensitivity in PTEN-null Pca cells.

METHODS

Wnt inhibitory factor-1 (WIF-1), an inhibitor of Wnt proteins, was transfected into PC-3 and DU145 Pca cells.

RESULTS

Akt was phosphorylated in PTEN-null PC-3 cells but underphosphorylated in PTEN-expressed DU145 cells. The levels of phosphorylated Akt in WIF-1 overexpressing PC-3 cells were lower than those in native or control vector-transfected PC-3 cells. However, WIF-1 showed no additional inhibition of already reduced Akt activity in DU145 cells. Overexpression of WIF-1 resulted in sensitizing PC-3 cells for paclitaxel to induce apoptosis. DU145 cells were more sensitive to paclitaxel but were not affected by WIF-1 transfection. The PI3K inhibitor LY294002 seemed to restore the chemosensitivity of native PC-3 cells like WIF-1 did.

CONCLUSIONS

Our results show that Wnt signaling is involved in Akt activation in Pca cells. Our data also indicate the possibility that Wnt and its signaling pathway can be therapeutic targets for PTEN-mutated advanced Pca.

Akt activation in renal cell carcinoma: contribution of a decreased PTEN expression and the induction of apoptosis by an Akt inhibitor

BACKGROUND

Akt has been implicated in the oncogenesis of human malignant tumors, because Akt regulates many key effector molecules involved in cell survival. PTEN (phosphatase and tensin homolog deleted on chromosome 10) negatively regulates Akt activation.

MATERIALS AND METHODS

The expression of phosphorylated Akt (p-Akt), total Akt and PTEN was analyzed by Western blotting in 45 renal cell carcinoma (RCC) patients. The Bad and phosphorylated Bad (p-Bad) statuses were analyzed in 20 RCC patients. A phosphatidylinositol ether analog was used as an Akt inhibitor to treat four RCC cell lines, namely Caki-1, KU19-20, SW839 and Caki-2.

RESULTS

The PTEN expression in RCC was observed to decrease and p-Akt expression to increase significantly in comparison with that in the corresponding normal kidney tissue. The PTEN expression inversely correlated with the p-Akt expression. These alterations were specific for clear cell type RCC, but not for papillary or chromophobe type RCC. Alterations in Bad phosphorylation were also specifically observed in clear cell type. The Akt inhibitor induced apoptosis in KU19-20 and Caki-2 cells with a high Akt activity.

CONCLUSIONS

A decreased expression of PTEN may be an underlying mechanism for Akt activation. An Akt inhibitor may be a therapeutic option for a subset of RCC with an elevated Akt activity.

A posterior lumbar approach for retroperitoneoscopic adrenalectomy: assessment of surgical efficacy

OBJECTIVES

To compare the efficacy of retroperitoneoscopic adrenalectomy by a posterior lumbar approach (RPA) with that obtained by a transperitoneal anterior approach (TAA) or retroperitoneal lateral flank approach (RLA).

METHODS

Fifty-one patients underwent endoscopic adrenalectomy by three approaches, including laparoscopic adrenalectomy by TAA in 33, retroperitoneoscopic adrenalectomy by RLA in 5, and retroperitoneoscopic adrenalectomy by RPA in 13.

RESULTS

The average adrenal tumor size was 27 mm (range 8 to 65). The average number of trocars required for RPA was 3.2 which was significantly less than that for TAA and for RLA (4.2 and 4.1, respectively). The conversion rate to open surgery was 9.1% by TAA, 0% by RLA, and 7.7% by RPA. The average operating time for TAA was 252 minutes, which was significantly shortened to 194 minutes by RLA and 142 minutes by RPA (P < 0.02). The average blood loss was 101 mL for TAA and was negligible by RLA and RPA (22 and 32 mL. respectively).

CONCLUSIONS

RPA allowed direct access to the main adrenal vascular supply before the gland was greatly manipulated. Endoscopic adrenalectomy by TAA or even by RLA required extra ports for retraction of liver, spleen, vena cava, or adrenal gland, with higher chance of vein avulsion. RPA was technically feasible and most effective for retroperitoneoscopic adrenalectomy in regard to the simplicity of vascular control. The operating time, perioperative morbidity, and cost were reduced with this approach.

Complications of laparoscopic and retroperitoneoscopic adrenalectomies in 370 cases in Japan: a multi-institutional study

A total of 370 laparoscopic adrenalectomies, including 311 transperitoneal (TP) and 59 retroperitoneal (RP) approaches, were performed in nine urologic centers, where the laparoscopic adrenalectomy was first begun independently in Japan, and their affiliated hospitals between January 1992 and September 1996. The clinical diagnoses of those 370 adrenal diseases were primary aldosteronism in 155 patients, Cushing's syndrome in 61. preclinical Cushing's syndrome in 21. pheochromocytoma in 16, nonfunctioning adenoma in 87, complicated cyst in ten, myelolipoma in nine, adrenal cancer in four and other diagnoses in eight (table 1). There was no mortality in this series. Intraoperative complication rate was 33/370 (9%) in total: 26/311(8%) in the TP procedures and 7/59 (12%) in the RP procedures (table 11). Postoperative complication rate was 24/370 (6%) in total: 22/311 (7%) in the TP procedures and 2/59 (3%) in the RP ones (table 111). Conversion rates to open surgery in total, in the TP and in the RP procedures were 13/370 (3.5%), 10/311 (3.2%) and 3/59 (5.1 %). respectively (table IV). Although the RP procedure has a lower morbidity rate compared to the TP procedure, more skill is required to overcome the drawback of the narrow working space and fewer anatomical landmarks.

Regulatory T-cell stability and plasticity in mucosal and systemic immune systems

Regulatory T cells (Treg) express the forkhead box p3 (Foxp3) transcription factor and suppress pathological immune responses against self and foreign antigens, including commensal microorganisms. Foxp3 has been proposed as a master key regulator for Treg, required for their differentiation, maintenance, and suppressive functions. Two types of Treg have been defined. Natural Treg (nTreg) are usually considered to be a separate sublineage arising during thymus differentiation. Induced Treg (iTreg) originate upon T cell receptor (TCR) stimulation in the presence of tumor growth factor beta. Although under homeostatic conditions most Treg in the periphery are nTreg, special immune challenges in the intestine promote more frequently the generation of iTreg. Furthermore, recent observations have challenged the notion that Treg are a stable sublineage, and they suggest that, particularly under lymphopenic and/or inflammatory conditions, Treg may lose Foxp3 and/or acquire diverse effector functions, especially in the intestine, which may contribute to uncontrolled inflammation.

The ND1 Subunit Constructs the Inhibitor Binding Domain in Bovine Heart Mitochondrial Complex I

The inhibitor binding domain in bovine complex I is believed to be constructed by multisubunits, but it remains to be learned how the binding positions of chemically diverse inhibitors relate to each other. To get insight into the inhibitor binding domain in complex I, we synthesized a photoreactive acetogenin [[125I](trifluoromethyl)phenyldiazirinylacetogenin, [125I]TDA], in which an aryldiazirine group serves as both a photoreactive group and a substitute for the gamma-lactone ring that is a common toxophore of numerous natural acetogenins, and carried out photoaffinity labeling to identify the labeled subunit using bovine heart submitochondrial particles (SMP). When SMP were UV-irradiated in the presence of [125I]TDA, radioactivity was predominantly incorporated into an approximately 30 kDa band on a SDS gel. Blue native gel electrophoresis of the [125I]TDA-labeled SMP revealed that the majority of radioactivity was observed in complex I. Analysis of complex I on a SDS gel showed a predominant peak of radioactivity at approximately 30 kDa. Immnoprecipitation of the [125I]TDA-labeled complex I with anti-bovine ND1 antibody indicated that the labeled protein is the ND1 subunit. A variety of complex I inhibitors such as piericidin A and rotenone efficiently suppressed the specific binding of [125I]TDA to ND1, indicating that they share a common binding domain. However, the suppression efficiency of Deltalac-acetogenin, a new type of complex I inhibitor synthesized in our laboratory, was much lower than that of the traditional inhibitors. Our results unequivocally reveal that the ND1 subunit constructs the inhibitor binding domain, though the contribution of this subunit has been challenged. Further, the present study corroborates our previous proposition that the inhibition site of Deltalac-acetogenins differs from that of traditional inhibitors.

Differential diagnosis of primary benign and malignant retroperitoneal tumors

BACKGROUND

Clinical differential diagnosis between malignant and benign tumors is important in order to select a therapeutic strategy for a primary retroperitoneal tumor.

METHODS

The clinical findings and radiological features of 25 patients with primary retroperitoneal tumors were retrospectively evaluated to find those signs that might contribute to the preoperative distinction between benign and malignant tumors.

RESULTS

Of 25 primary retroperitoneal tumors, 15 were benign. This may reflect the increased number of incidentally found small benign tumors. There were significant associations between the presence of symptoms and malignancy (P < 0.05), between irregular margins on imaging and malignancy (P < 0.05) and between the absence of calcification and malignancy (P < 0.05). Malignant tumors were significantly larger than benign tumors (11.45 +/- 1.90 cm vs. 5.31 +/- 0.43 cm). A retroperitoneal tumor scoring system was developed to distinguish primary retroperitoneal benign tumors from their malignant counterparts based on the: 1) maximum diameter equal to or larger than 5.5 cm, 2) presence of symptoms, 3) absence of calcification, 4) presence of irregular margins, and 5) presence of cystic degeneration or necrosis. A significant correlation was found between the incidence of malignant tumors and the total retroperitoneal tumor score (P < 0.05).

CONCLUSION

This study suggests that the size of tumor, the presence of symptoms, irregular margins, and the absence of calcification may be valuable predictors of primary retroperitoneal malignant tumor.

Induction of apoptosis of cytokine-producing bladder cancer cells by adenovirus-mediated IkappaBalpha overexpression

We investigated whether the cell growth and apoptosis of multiple cytokine-producing bladder cancer cells can be regulated by nuclear factor kappaB (NF-kappaB). The bladder cancer cell line KU-19-19, obtained from a 76-year-old man who demonstrated marked leukocytosis, produces multiple cytokines and demonstrates autocrine growth by granulocyte colony-stimulating factor (G-CSF). Electrophoretic mobility shift assay (EMSA) revealed that NF-kappaB was activated in KU-19-19 but not in other bladder cancer cell lines (KU-1, KU-7, or T-24, respectively). The inhibition of NF-kappaB DNA-binding activity with adenovirus vectors expressing the stable form of the NF-kappaB inhibitor IkappaBalpha (multiplicity of infection [MOI] of 10) inhibited growth and induced apoptosis of KU-19-19, but not KU-1, KU-7, or T-24. The production of several cytokines was suppressed significantly in KU-19-19 by this gene delivery. Although dexamethasone (10 microM) could also suppress cytokine production, it did not induce dramatic cell death in KU-19-19 because it could not inhibit NF-kappaB activation stably and strongly. These results suggest that NF-kappaB activation maintains the cell viability as well as regulates cytokine production in cytokine-producing cancer cells and therefore these in vitro experiments support a rationale for preclinical in vivo studies to demonstrate growth inhibition in established tumors.