Tailoring nonuniform local orbital angular momentum density.

As is well known, a light beam with a helical phase carries an optical orbital angular momentum (OAM), which can cause the orbital motion of trapped microparticles around the beam axis. Usually, the speed of the orbital motion is uniform along the azimuthal direction and depends on the amount of OAM and the light intensity. Here, we present the reverse customized method to tailor the nonuniform local OAM density along the azimuthal direction of the focal field, which has a hybrid polarization distribution and maintains a doughnut-shaped intensity profile. Theoretical analysis and experimental results about the orbital motion of the trapped polystyrene sphere show that the nonuniform local OAM density can be tailored by manipulating the polarization states of the focal field. Our results provide an ingenious way to control the local tangential optical force and the speed of the orbital motion of particles driven by the local OAM density and will promote exciting possibilities for exploring ways to control the mechanical dynamics of microparticles in optical trapping and microfluidics.

Clinical effect of pulmonary rehabilitation in patients with mechanical ventilation: A meta-analysis.

OBJECTIVE: To systematically evaluate the clinical efficacy of pulmonary rehabilitation in patients with mechanical ventilation in an intensive care unit (ICU). METHODS: Relevant studies were identified in the PubMed, Web of Science, National Library of Medicine, China National Knowledge Infrastructure and Wanfang databases. A meta-analysis was performed after screening based on the inclusion and exclusion criteria, data extraction and literature quality evaluation. RESULTS: In total, 19 studies involving 2181 participants were included. The results of the meta-analysis revealed that compared with patients with conventional rehabilitation measures, patients with pulmonary rehabilitation measures had a higher offline success rate (relative risk (RR) = 1.16; 95% confidence interval (CI): 1.09, 1.24; p < 0.00001) and higher arterial oxygen partial pressure levels (mean difference (MD) = 8.96; 95%CI: 5.98, 11.94; p < 0.0001) and these measures significantly shortened the duration of mechanical ventilation (standardised MD (SMD) = -1.08; 95%CI: -1.58, -0.59; p < 0.0001) and ICU stay (SMD = -1.41; 95%CI: -1.94, -0.88; p < 0.0001). Aspiration significantly reduced the incidence of ventilator-associated pneumonia (RR = 0.35; 95%CI: 0.24, 0.51; p < 0.00001) and deep vein thrombosis (RR = 0.32; 95%CI: 0.13, 0.76; p = 0.01) in ICU patients with mechanical ventilation. CONCLUSION: Pulmonary rehabilitation measures can improve the success rate of weaning from mechanical ventilation in ICU patients, shorten the time of mechanical ventilation and ICU hospitalisation and reduce the incidence of related adverse reactions, but the impact on mortality requires further study.

A novel detection method for neuronal death indicates abnormalities in intracellular membranous components in neuronal cells that underwent delayed death.

Acute neuronal degeneration is always preceded under the light and electron microscopes by a stage called microvacuolation, which is characterized by a finely vacuolar alteration in the cytoplasm of the neurons destined to death. In this study, we reported a method for detecting neuronal death using two membrane-bound dyes, rhodamine R6 and DiOC6(3), which may be associated with the so-called microvacuolation. This new method produced a spatiotemporally similar staining pattern to Fluoro-Jade B in kainic acid-damaged brains in mice. Further experiments showed that increased staining of rhodamine R6 and DiOC6(3) was observed only in degenerated neurons, but not in glia, erythrocytes, or meninges. Different from Fluoro-Jade-related dyes, rhodamine R6 and DiOC6(3) staining is highly sensitive to solvent extraction and detergent exposure. Staining with Nile red for phospholipids and filipin III for non-esterified cholesterol supports that the increased staining of rhodamine R6 and DiOC6(3) might be associated with increased levels of phospholipids and free cholesterol in the perinuclear cytoplasm of damaged neurons. In addition to kainic acid-injected neuronal death, rhodamine R6 and DiOC6(3) were similarly useful for detecting neuronal death in ischemic models either in vivo or in vitro. As far as we know, the staining with rhodamine R6 or DiOC6(3) is one of a few histochemical methods for detecting neuronal death whose target molecules have been well defined and therefore may be useful for explaining experimental results as well as exploring the mechanisms of neuronal death.

Cold-inducible RNA binding protein agonist enhances the cardioprotective effect of UW solution during extended heart preservation.

In heart transplantation, time restriction is an unavoidable thorny problem during cardiac transport. Cold storage is an important organ preservation method in donor heart transport. Cold-inducible RNA binding protein (CIRBP) has been proven to play a protective role under cold stress. In this study, we investigated the role of CIRBP in hypothermic cardioprotection during heart preservation in UW solution and explored a new approach to extend the heart preservation time. Cirbp-knockout (Cirbp-/- ), Cirbp-transgenic (Cirbp-Tg), and wild-type rats were, respectively, randomized into two groups based on various heart preservation times (6 or 12-hour group) (n = 8 per group). After preservation in UW solution, all hearts were mounted on a Langendorff apparatus and underwent measurement of cardiac parameters, histological analysis, and molecular study. Within the 6-hour preservation group, no significant difference was found in cardiac functions and histological changes between different rat species. However, after 12 hours of preservation, Cirbp-/- rat hearts showed more apoptosis and worse cardiac function, but less apoptosis and better cardiac function were observed in Cirbp-Tg rat hearts. Furthermore, we found CIRBP-mediated cardiac ubiquinone (CoQ10 ) biosynthesis plays an important role in extending heart preservation, and ubiquinone biosynthesis protein COQ9 was an essential down-stream regulator during this process. Finally, we found that zr17-2, a CIRBP agonist, could enhance the expression of CIRBP, which further enhances the synthesis of CoQ10 and promotes scavenging of reactive oxygen species and ATP production to extend heart preservation. This study demonstrated that CIRBP-enhanced CoQ10 biosynthesis during hypothermic heart preservation and zr17-2-supplemented UW solution could be a promising approach to ameliorate heart damage and extend heart preservation during cardiac transport.

Social Support, Health Literacy, and Health Care Utilization Among Older Adults.

The purpose of this study was to explore the relationship between social support, health literacy, and health care utilization in older Chinese adults. A cross-sectional survey design was employed. Data were collected from 32 nursing homes from Urumqi in Xinjiang of China. A total of 1486 respondents completed a pack of questionnaires. The average health literacy level of older adults in nursing homes was relatively low, only 73.68 ± 29.42 points; the average social support level was also relatively low, only 31.42 ± 7.12 points (lower than domestic norm of Chinese residents, P < .001). Both values were below the midpoint for the overall population, indicating a sample with below-average levels of healthy literacy and social support. Low social support levels are associated with poor health literacy and greater likelihood of hospital admission (P < .05). Social support was significantly associated with health literacy. Improving the quantity and quality of social support may be an effective means to obtain better health literacy and lower hospital admissions.

Inflammation markers are associated with frailty in elderly patients with coronary heart disease.

The neutrophil-to-lymphocyte ratio (NLR) and red blood cell distribution width (RDW) are important indicators of adverse outcomes and have predictive value for many diseases; however, the relationships between frailty, and the NLR and RDW in patients with coronary heart disease (CHD) have not been determined. In this cross-sectional study, we investigated the association between frailty, and the NLR and RDW in elderly CHD patients ≥ 60 years of age. Frailty was defined according to frailty phenotype. Of 345 patients enrolled in the study, 22.6%, 58.3%, and 19.1% were characterized as robust, pre-frail, and frail, respectively. A significant positive correlation was observed between frailty and the NLR (r = 0.169) and RDW (r = 0.196). After adjusting for confounders, linear regression analyses showed that participants in the 4th quartile of the NLR or RDW were more likely to have a higher frailty phenotype score. Based on multivariable logistic regression, patients in the 4th quartile of the NLR and RDW, the fully-adjusted odds ratios for incident frailty were 2.894 (p = 0.011) and 2.494 (p = 0.040), respectively. Our findings indicate that frailty is associated with the NLR and RDW in elderly patients with CHD.

The effects of calcineurin inhibitor FK506 on actin cytoskeleton, neuronal survival and glial reactions after pilocarpine-induced status epilepticus in mice.

After status epilepticus (SE), actin cytoskeleton (F-actin) becomes progressively deconstructed in the hippocampus, which is consistent with the delayed pyramidal cell death in both time course and spatial distribution. A variety of experiments show that calcineurin inhibitors such as FK506 are able to inhibit the SE-induced actin depolymerization. However, it is still unclear what changes happen to the F-actin in the epileptic brain after FK506 treatment. A pilocarpine model of SE in mice was used to examine the effects of FK506 on the F-actin in the hippocampal neurons. The post SE (PSE) mice with or without FK506 treatment were monitored consecutively for 14 days to examine the frequency and duration of spontaneous seizures. The effects of FK506 on the activity of cofilin and actin dynamics were assessed at 7 and 14 d PSE by western blots. The organization of F-actin, neuronal cell death, and glial reactions were investigated by phalloidin staining, histological and immunocytochemical staining, respectively. As compared to the PSE + vehicle mice, FK506 treatment significantly decreased the frequency and duration of spontaneous seizures. Relative to the PSE + vehicle mice, western blots detected a partial restoration of phosphorylated cofilin and a significant increase of F/G ratio in the hippocampus after FK506 treatment. In the PSE + vehicle mice, almost no F-actin puncta were left in the CA1 and CA3 subfields at 7 and 14 d PSE. FK506-treated PSE mice showed a similar decrease of F-actin, but the extent of damage was significantly ameliorated. Consistently, the surviving neurons became significantly increased in number after FK506 treatment, relative to the PSE + vehicle groups. After FK506 treatment, microglial reaction was partially inhibited, but the expression of GFAP was not significantly changed, compared to the PSE + vehicle mice. The results suggest that post-epileptic treatment with FK506 ameliorated, but could not stop the deconstruction of F-actin or the delayed neuronal loss in the PSE mice.

Tetramethylpyrazine alleviated cytokine synthesis and dopamine deficit and improved motor dysfunction in the mice model of Parkinson's disease.

It was previously reported that cytokines and neurotoxins released from activated inflammatory cells induced the loss of projecting dopaminergic neurons in the substantia nigra, which triggered the pathogenesis of PD. The present study investigated the effect of treatment with tetramethylpyrazine (TMP) on the central cytokine synthesis, striatal dopamine content and glutamatergic transmission, and behavioral performance in the rotarod task in mice injected with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Treatment with TMP significantly improved the behavioral performance in the rotarod task in mice injected with MPTP. It also decreased the upregulation of cytokines (tumor necrosis factor-α and interleukin-1ß) in the substantia nigra and striatum in these modeled mice. Furthermore, treatment with TMP significantly improved the dopamine deficits and attenuated the upregulation of striatal basal glutamatergic strength in the striatum of mice injected with MPTP. These results indicated that TMP might serve as a novel approach for the treatment of patients with PD.

The rearrangement of filamentous actin in mossy fiber synapses in pentylenetetrazol-kindled C57BL/6 mice.

Chemical kindling, as an experimental model of epileptogenesis, is induced by repetitive administration of subconvulsive amount of excitatory drugs. Kindled mice do not typically display spontaneous recurrent seizures, but are instead characterized by enhanced seizure susceptibility to convulsive stimulations. In order to provide insights into the aberrant synaptic plasticity during kindling, this study investigated the effect of pentylenetetrazol (PTZ) kindling on filamentous actin (F-actin) in mossy fiber synapses in C57BL/6 mice. Phalloidin labeling of F-actin showed that F-actin puncta were increased in number in the stratum lucidum of CA3 region in the hippocampus after kindling. The rearrangement of F-actin seemed to occur presynaptically, since synapsin I, a specific marker for mossy fiber terminals, was also up-regulated. Such subtle structural modifications occurring in the synapses are thought to contribute to the long-lasting increased sensitivity in the PTZ-kindled C57BL/6 mice.

Single-incision laparoscopic resection of Bismuth I hilar cholangiocarcinoma.

INTRODUCTION: Laparoscopic hilar cholangiocarcinoma is rarely performed because of its aggressive growth and complicated anatomy. The authors successfully performed single-incision laparoscopic resection of Bismuth I hilar cholangiocarcinoma in 2 cases. METHOD: Two cases with Bismuth I cholangiocarcinoma were chosen for the laparoscopic surgery. Segmental bile duct resection and hepatoduodenal ligament lymphadenectomy were performed using single-incision laparoscopic technique with conventional instruments. RESULTS: Two operations were successfully performed without conversion. The operation time was 300 and 350 minutes, respectively. The margins of proximal and distal bile ducts were negative. The hospital stay was 6 and 9 days, respectively. One dosage of analgesic was administered after surgery. The abdominal wound recovered very well with good cosmesis. CONCLUSION: Single-incision laparoscopic surgery cholangiocarcinoma resection can be optional in strictly selected patients with Bismuth I cholangiocarcinoma. Long-term follow-up and more data are needed to evaluate its benefits.

Enhancement of the sensitivity of renal cell carcinoma cells to fas-mediated cytotoxicity and apoptosis by the selective cyclooxygenase-2 inhibitor JTE-522.

BACKGROUND: Cyclooxygenase-2 (COX-2) is a key enzyme involved in the production of prostaglandins and its inhibitors have been shown to induce apoptosis in a variety of cancer cells. We reasoned that combination treatment of renal cell carcinoma (RCC) cells with COX-2 inhibitors and anticancer agents may result in synergistic apoptosis. We examined whether the selective COX-2 inhibitor JTE-522 synergizes with anticancer agents in cytotoxicity and apoptosis against RCC cells. METHODS: The cytotoxicity of the selective COX-2 inhibitor JTE-522 and other anticancer agents against the RCC cell lines and the normal renal cell line was determined by the microculture tetrazolium dye assay. RESULTS: JTE-522 was cytotoxic against the Caki-1 RCC cell line. JTE-522 and anti-Fas monoclonal antibody (CH-11) exhibited a synergistic cytotoxic effect against Caki-1 cells. In contrast, JTE-522 in combination with 5-fluorouracil, adriamycin, cis-diamminedichloroplatinum, or interferon-alpha, all commonly used clinically, resulted in an additive cytotoxic effect. Synergy achieved in cytotoxicity with JTE-522 and CH-11 was shown to be due to apoptosis. CONCLUSIONS: The present study demonstrated that the selective COX-2 inhibitor JTE-522 had a cytotoxic effect on RCC and that synergistic cytotoxicity against RCC was obtained with JTE-522 in combination with anti-Fas monoclonal antibody. These results suggest that selective COX-2 inhibitors in combination with immunotherapy may be useful in treating patients with RCC.

Heterogeneous expression of the voltage-gated calcium channel alpha2 subunit and the voltage-gated sodium channel alpha subunit in chicken spinal motoneurons.

The localization of the voltage-gated calcium channel (VGCC) alpha2 and the voltage-gated sodium channel (VGSC) alpha subunits was immunohistochemically investigated in chicken spinal motoneurons. Approximately 83% and 46% of spinal motoneurons were positive for VGCCalpha2 and VGSCalpha subunits, respectively. Almost all VGSCalpha subunit-positive motoneurons exhibited the VGCCalpha2 subunit immunoreactivity. There were different patterns in occurrence, intensity or nuclear/cytoplasmic stainability of the VGCCalpha2 and VGSCalpha subunits among the motoneurons. This study presents the first cellular morphological evidence for the VGCCalpha2 and VGSCalpha subunits in spinal motoneurons, postulating that the heterogeneous expression of VGCCalpha2 and VGSCalpha subunits in the motoneurons may reflect various motor activities.

Activation of cerebral peroxisome proliferator-activated receptors gamma exerts neuroprotection by inhibiting oxidative stress following pilocarpine-induced status epilepticus.

Status epilepticus (SE) can cause severe neuronal loss and oxidative damage. As peroxisome proliferator-activated receptor gamma (PPARgamma) agonists possess antioxidative activity, we hypothesize that rosiglitazone, a PPARgamma agonist, might protect the central nervous system (CNS) from oxidative damage in epileptic rats. Using a lithium-pilocarpine-induced SE model, we found that rosiglitazone significantly reduced hippocampal neuronal loss 1 week after SE, potently suppressed the production of reactive oxygen species (ROS) and lipid peroxidation. We also found that treatment with rosiglitazone enhanced antioxidative activity of superoxide dismutase (SOD) and glutathione hormone (GSH), together with decreased expression of heme oxygenase-1 (HO-1) in the hippocampus. The above effects of rosiglitazone can be blocked by co-treatment with PPARgamma antagonist T0070907. The current data suggest that rosiglitazone exerts a neuroprotective effect on oxidative stress-mediated neuronal damage followed by SE. Our data also support the idea that PPARgamma agonist might be a potential neuroprotective agent for epilepsy.

Immunohistochemical demonstration of the calcium channel alpha2 subunit in the chicken dorsal root ganglion and spinal cord: a special reference to colocalization with calbindin-D28k in dorsal root ganglion neurons.

We used immunohistochemical methods to examine the distribution of the calcium channel alpha2 (CCalpha2) subunit in the chicken spinal cord and dorsal root ganglion (DRG) neurons and determine its relationship with calbindin-D28k (CB) in the DRG neurons. In the spinal cord, CCalpha2 subunit was detected in nerve terminals, which were observed as dot-like structures, and in laminae I, II, III and Lissauer's tract in the dorsal horn. In the DRG neurons, approximately 65% of the total neurons were CCalpha2 subunit positive, and most (86%) of these neurons were small to medium sized, suggesting that the CCalpha2 subunit and/or a complex of the CCalpha2 and delta subunits is possibly localized in a number of nociceptive neurons. A majority (77%) of the positive neurons showed CB immunoreactivity and most (88%) of these neurons were small to medium sized. This may indicate a close correlation between the CCalpha2 subunit and CB in the nociceptive neurons. Thus, it is postulated that the mode of nociceptive transmission may involve a cellular Ca(2+)-regulating system that consists of both Ca(2+) entry via calcium channels with the alpha2delta subunit and intracellular Ca(2+)-binding activity of CB in the nociceptive neurons of the DRG.

Mast cells appearing in long-term skeletal muscle cell cultures of rat.

Mast cells are known to be involved in type I allergy and to be localized in almost all tissues in the body. However, they have slightly different properties depending on their tissue of residence. Although mast cells are found in skeletal muscle tissue, there have been no reports of their appearance in cultured skeletal muscles. We report here that mast cells appear in long-term cultures of skeletal muscles from neonatal rats and rat fetuses. When muscle cells were disseminated and cultured in minimum essential medium with 10% fetal calf serum and 10% horse serum, oval cells containing large granules started to appear on myotube sheets at 5 days of culture. These oval cells continued to proliferate for 2-3 months, and showed immunoreactivity for histamine, tryptase, Fc(epsilon)RI, and c-kit. They showed metachromatic staining with 0.5% toluidine blue at pH 0.5 and were stained with both Alcian blue and safranin. Biochemically measured histamine content per dish was significantly higher in 2-month than in 5-day culture. From these results, we concluded that these oval cells were mast cells. Because proteases from mast cells have been reported previously to affect myoblast proliferation, the present findings suggest that there may be some interaction between mast cells and muscle cell proliferation or differentiation. The present finding that mast cells are easily obtained from ordinary skeletal muscle cultures provides a useful method for the study of the diverse functions of mast cells.

Overexpression of XIAP expression in renal cell carcinoma predicts a worse prognosis.

X-linked inhibitor of apoptosis protein (XIAP) is the most potent caspase-inhibitory IAP family member and a negative regulator of various apoptotic stimuli. Thus, XIAP overexpression in cancer cells may select for tumor cell survival following various cytotoxic therapeutic modalities. The anatomical staging system in renal cell carcinoma (RCC) currently provides good prognostic information, albeit insufficient. We hypothesize that overexpression of XIAP in RCC may serve as a molecular prognostic marker in RCC and improve the staging of RCC. This study examined the protein level of XIAP in lysates from surgical specimens of 109 patients with RCC and 109 normal kidney specimens from the same patients. The level of XIAP expression was quantified by Western blot analysis using non-fixed fresh frozen tissues of RCCs and normal kidneys. Results indicated that the mean level of XIAP expression was higher in RCC compared to autologous normal kidney, and the XIAP expression level in 38/109 (35%) of RCC was more than 2-fold greater than that in normal kidney tissue. In Stage I/II RCC, the mean XIAP expression level was almost identical to that detected in normal kidney, whereas XIAP expression in Stage III/IV was 2.5-fold higher than that in Stage I/II RCC. Levels of XIAP expression also correlated with the grade of RCC. Patients with RCC with low XIAP expression had a longer postoperative disease-specific survival as compared to those with high expression in the 5-year follow-up. The suggested role of XIAP in the regulation of resistance in apoptosis was examined in vitro following treatment of RCC cell lines with XIAP antisense oligonucleotide and the cells were sensitized to both Fas-mediated and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-mediated apoptosis. The present study demonstrates at the protein level that XIAP is overexpressed in RCC, and that high XIAP expression in RCC predicted a worse prognosis. In addition, XIAP antisense oligonucleotide sensitized RCC to Fas/TRAIL-induced apoptosis. These results suggest that XIAP expression in RCC may be used as a prognostic parameter, and that downregulation or inhibition of XIAP expression in RCC may reverse immune resistance.

Subsurface cisterna-lined axonal invaginations and double-walled vesicles at the axonal-myelin sheath interface.

The axonal-myelin sheath interface of vertebrate myelinated axons possesses special structural complexities, and there may be an intercellular macromolecular traffic transversing the periaxonal cleft that spans the internodal axon. By conventional electron microscopy and serial sectioning, we observed a category of double-walled vesicles at the axonal-myelin sheath interface, which often contained ribosome-like particles or endoplasmic reticulum. Some of them were demonstrated to continue with the subjacent axon with a thin stalk. In addition, we described a special category of axonal invaginations, probably mediated by subsurface cisternae. The functional implications of these specialized structures were discussed.

Beyond the initial axon segment of the spinal motor axon: fasciculated microtubules and polyribosomal clusters.

Dense undercoating, microtubular fascicles and scattered polyribosomal clusters have until now been considered to be the three structural features of the initial segment, and were thought not to extend beyond the initial segment into the myelinated parts of the axon. The aim of the present study was to make clear whether there is a sudden change in morphology between the unmyelinated and myelinated part. We followed spinal motor axons from the initial segment to the first internode by conventional electron microscopy and serial sectioning, and found that the microtubular fascicles and polyribosomal clusters do exist in the internodal axoplasm. The fasciculated microtubules were observed mainly in the first paranode. The polyribosomal clusters were found along the course of the first internode at a random distance, however, they occurred mainly in the proximal part of the first internode. The proportion of sections in which ribosomes were found, i.e. the incidence of ribosomes, in the first 30-microm-long portion was 71 +/- 24% (mean +/- SD, n = 4), and significantly different from that in the second 30-microm-long portion (3.2 +/- 1.3%) (mean +/- SD, n = 4) (P < 0.005). The more distal part of the first internode was not investigated.

An immunocytochemical study of calbindin-D28K in laminae I and II of the dorsal horn and spinal ganglia in the chicken with special reference to the relation to substance P-containing primary afferent neurons.

The localization of calbindin-D28K (CB) was studied immunocytochemically in laminae I and II of the dorsal horn and in spinal ganglia in the chicken, and compared with the distribution of substance P (SP) using double immunolabeling. At the light microscopic level, CB immunoreactivity was observed most intensely in the lamina II using the avidin-biotinylated peroxidase complex (ABC) and immunofluorescence methods. At the electron microscopic level using the ABC method, CB immunoreactivity was observed in the following three neuronal elements: 1) the scalloped central terminal with many dense-cored vesicles (DCVs) in the synaptic glomerulus; 2) some vesicle-containing dendrites (VCDs) inside or outside the synaptic glomerulus; and 3) some axon terminals outside the synaptic glomerulus. The CB-immunoreactive (IR) VCDs in the synaptic glomerulus often formed reciprocal synapses with the central terminal. Strong immunoreactivity was observed at the postsynaptic membrane of CB-IR elements. Double immunofluorescence and immunolabeling methods at the electron microscopic level showed that CB and SP colocalized in the scalloped central terminal with DCVs of the synaptic glomerulus. Almost all SP-IR neurons in the spinal ganglion revealed the coexistence of CB in serial sections in the chicken. In light of previous biochemical and physiological reports, our findings suggest that CB - coexisting with SP - plays an important role in the control of pain transmission through its strong Ca(2+)-buffering action in the chicken.

Downregulation of Smac/DIABLO expression in renal cell carcinoma and its prognostic significance.

PURPOSE: Second mitochondria-derived activator of caspase/direct inhibitor of apoptosis-binding protein with low pI (Smac/DIABLO) was recently identified as a protein that is released from mitochondria in response to apoptotic stimuli and promotes apoptosis by antagonizing inhibitor of apoptosis proteins. Furthermore, Smac/DIABLO plays an important regulatory role in the sensitization of cancer cells to both immune- and drug-induced apoptosis. However, little is known about the clinical significance of Smac/DIABLO in various cancers, including renal cell carcinoma (RCC). This study examined Smac/DIABLO expression in 78 healthy kidneys and 78 RCCs. MATERIALS AND METHODS: The level of Smac/DIABLO expression was quantified by Western blot analysis using nonfixed fresh frozen tissues. RESULTS: The expression of Smac/DIABLO was lower in RCC compared with the autologous normal kidney. Sixty-four (82%) of 78 of RCC expressed Smac/DIABLO, and 18% were negative, whereas 100% of normal kidney tissues were positive. In stage I/II RCC, 96% expressed Smac/DIABLO, whereas only 50% expressed Smac/DIABLO in stage III/IV. Smac/DIABLO expression inversely correlated with the grade of RCC. Patients with RCC expressing Smac/DIABLO had a longer postoperative disease-specific survival than those without Smac/DIABLO expression in the 5-year follow-up. Transfection with Smac/DIABLO cDNA enhanced tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) -mediated and cisplatin-mediated cytotoxicity in RCC. CONCLUSION: The present study demonstrates for the first time that Smac/DIABLO expression was downregulated in RCC and that no Smac/DIABLO expression in RCC predicted a worse prognosis. In addition, transfection with Smac/DIABLO sensitized RCC to TRAIL/cisplatin-induced apoptosis. These results suggest that Smac/DIABLO expression in RCC may be used as a prognostic parameter, and that enhancement of Smac/DIABLO expression in RCC may potentiate immunotherapy and chemotherapy.