Interleukin-4 induces senescence in human renal carcinoma cell lines through STAT6 and p38 MAPK.

Interleukin (IL)-4, originally identified as a lymphocyte growth factor, can directly inhibit growth of certain tumor cell types. We reported previously that IL-4 induced cell cycle arrest in G1 phase through an increase in p21(WAF1/CIP1) expression in human renal cell carcinoma (RCC) cell lines. In the present study, we investigated the underlying mechanism of IL-4-induced growth inhibition. In four of six human RCC cell lines, including Caki-1, A498, SNU482, and SNU228, IL-4 induced cellular senescence as demonstrated by enlarged and flattened morphology, increased granularity, and senescence-associated-ß-galactosidase (SA-ß-gal) staining. Signal tranducer and activator of transcription 6 (STAT6) and p38 MAPK were found to mediate IL-4-induced growth inhibition and cellular senescence. Both of these molecules were activated by 10 min after IL-4 treatment, and inhibition of their activity or expression prevented growth suppression and cellular senescence induced by IL-4. Inhibiting or silencing either STAT6 or p38 MAPK alone partially reduced the effect of IL-4, whereas inhibiting or silencing both molecules exerted an additive effect and almost completely abrogated the effect of IL-4. Thus STAT6 and p38 MAPK appeared to independently mediate IL-4-induced growth inhibition and cellular senescence. The p21(WAF1/CIP1) up-regulation that accompanied growth inhibition and cellular senescence by IL-4 was also attenuated additively when p38 MAPK and STAT6 were silenced. Taken together, these results show that IL-4 induces cellular senescence through independent signaling pathways involving STAT6 and p38 MAPK in some human RCC cell lines.

Reliability of fractional anisotropy measurement for children with cerebral palsy.

OBJECTIVE: Periventricular leukomalacia (PVL) is the leading cause of disability in children with cerebral palsy (CP). Diffusion tensor imaging (DTI) is a magnetic resonance imaging technique for detecting microstructural lesions of white matter. Fractional anisotropy (FA) is a widely used DTI index with clinical significance in children with CP. This study aims to estimate the reliability of FA for children with CP. DESIGN: Four observers measured FA values in 78 children with spastic CP from PVL. Region of interests (ROIs) were placed in three anatomical loci at each side: medial and lateral portions of posterior limb of internal capsule and ascending sensory tract. Intra- and interobserver reliability indices including intraclass correlation coefficient (ICC), standard error of measurement, smallest real difference percentage (SRD%), and limit of agreement using Bland-Altman analysis were examined. RESULTS: Intraobserver ICCs were 0.85 or greater in all ROIs, and SRD% ranged from 3.59 to 12.33%. Interobserver ICCs exceeded 0.90 in all ROIs, and the SRD% were less than 10%. The Bland-Altman analysis showed good intra- and interobserver agreements. The reliability was not affected by severity of impairment. CONCLUSIONS: Reliability of DTI-derived FA value using ROIs was satisfactory in children with PVL.

Panaxydol induces apoptosis through an increased intracellular calcium level, activation of JNK and p38 MAPK and NADPH oxidase-dependent generation of reactive oxygen species.

Panaxydol, a polyacetylenic compound derived from Panax ginseng roots, has been shown to inhibit the growth of cancer cells. In this study, we demonstrated that panaxydol induced apoptosis preferentially in transformed cells with a minimal effect on non-transformed cells. Furthermore, panaxydol was shown to induce apoptosis through an increase in intracellular Ca(2+) concentration ([Ca(2+)](i)), activation of JNK and p38 MAPK, and generation of reactive oxygen species (ROS) initially by NADPH oxidase and then by mitochondria. Panaxydol-induced apoptosis was caspase-dependent and occurred through a mitochondrial pathway. ROS generation by NADPH oxidase was critical for panaxydol-induced apoptosis. Mitochondrial ROS production was also required, however, it appeared to be secondary to the ROS generation by NADPH oxidase. Activation of NADPH oxidase was demonstrated by the membrane translocation of regulatory p47(phox) and p67(phox) subunits and shown to be necessary for ROS generation by panaxydol treatment. Panaxydol triggered a rapid and sustained increase of [Ca(2+)](i), which resulted in activation of JNK and p38 MAPK. JNK and p38 MAPK play a key role in activation of NADPH oxidase, since inhibition of their expression or activity abrogated membrane translocation of p47(phox) and p67(phox) subunits and ROS generation. In summary, these data indicate that panaxydol induces apoptosis preferentially in cancer cells, and the signaling mechanisms involve a [Ca(2+)](i) increase, JNK and p38 MAPK activation, and ROS generation through NADPH oxidase and mitochondria.

Glycogen synthase kinase 3beta phosphorylates p21WAF1/CIP1 for proteasomal degradation after UV irradiation.

UV irradiation has been reported to induce p21(WAF1/CIP1) protein degradation through a ubiquitin-proteasome pathway, but the underlying biochemical mechanism remains to be elucidated. Here, we show that ser-114 phosphorylation of p21 protein by glycogen synthase kinase 3beta (GSK-3beta) is required for its degradation in response to UV irradiation and that GSK-3beta activation is a downstream event in the ATR signaling pathway triggered by UV. UV transiently increased GSK-3beta activity, and this increase could be blocked by caffeine or by ATR small interfering RNA, indicating ATR-dependent activation of GSK-3beta. ser-114, located within the putative GSK-3beta target sequence, was phosphorylated by GSK-3beta upon UV exposure. The nonphosphorylatable S114A mutant of p21 was protected from UV-induced destabilization. Degradation of p21 protein by UV irradiation was independent of p53 status and prevented by proteasome inhibitors. In contrast to the previous report, the proteasomal degradation of p21 appeared to be ubiquitination independent. These data show that GSK-3beta is activated by UV irradiation through the ATR signaling pathway and phosphorylates p21 at ser-114 for its degradation by the proteasome. To our knowledge, this is the first demonstration of GSK-3beta as the missing link between UV-induced ATR activation and p21 degradation.

IL-4 inhibits proliferation of renal carcinoma cells by increasing the expression of p21WAF1 and IRF-1.

Interleukin (IL)-4 inhibits proliferation of several human cancer cell lines in vitro. Although IL-4 is known to regulate proliferation of lymphocytes by modulating p27KIP1 expression, the mechanism involved in the IL-4-induced growth inhibition of nonhematopoietic cancer cells has not been fully elucidated. Previously, we reported that IL-4 suppressed proliferation of human renal cell carcinoma (RCC) cell lines in vitro. Here, we show that IL-4 inhibits cell cycle progression at the G1 phase in Caki-1 cells by increasing the expression of p21WAF1 and interferon regulatory factor (IRF)-1, and decreasing the cyclin dependent kinase (CDK) 2 activity. Up-regulation of p21WAF1 and IRF-1 expression is transcriptional, but independent of p53. The levels of p21WAF1 and IRF-1 proteins were enhanced as early as 1 h after IL-4 treatment. CDK2 activity started to decline at 4 h after IL-4 treatment, and by 24 h, was approximately 50% of the control. Neither the protein expressions of p27KIP1 and p16INK4a, nor the phosphorylation level of pRb was changed. The importance of p21WAF1 and IRF-1 in the growth inhibition induced by IL-4 was confirmed by antisense oligonucleotide transfection. Both of p21WAF1 and IRF-1 antisense oligonucleotides prevented IL-4-mediated growth inhibition by approximately 30% compared to the respective sense oligonucleotides. In summary, our study indicated that p21WAF1 and IRF-1 mediate the growth inhibitory effect of IL-4 in human RCC cells.

Stepwise rehabilitation of the triple amputee combined with dysfunction of the sound limb.

To find a multiple amputee more severe than a triple amputee is not easy. This is a report of a 36-year-old patient with right knee disarticulation, left trans-femoral amputation and right elbow disarticulation due to peripheral ischemic necrosis, when he was applied vasopressor in septic shock condition. His left hand was also 2nd, 3rd, 4th, and 5th distal interphalangeal joint disarticulation status, and it was more difficult for him to do rehabilitation program, such as donning and doffing the prostheses. For more efficient rehabilitation training program, we first focused on upper extremities function, since we believed that he might need a walking aid for gait training later. After 13 weeks of rehabilitation program, he has become sit to stand and walk short distance independently with an anterior walker. Although he still needs some assistance with activities of daily living, his Functional Independence Measure score improved from 48 to 90 during the course of 13 weeks.

Epidemiologic change of patients with spinal cord injury.

OBJECTIVE: To evaluate the epidemiologic change of patients with spinal cord injury who were admitted to a Rehabilitation Hospital, Yonsei University College of Medicine, during 1987-1996 and 2004-2008. METHODS: Medical records of 629 patients with spinal cord injury admitted to the Rehabilitation Hospital, Yonsei University College of Medicine, from 2004 to 2008 were collected and reviewed retrospectively. RESULTS: The male-to-female ratio decreased to 2.86:1, the mean age at injury increased, nontraumatic etiology increased, traffic accident remained to be the most common in traumatic spinal cord injury, and falling increased significantly. Tumor was the most common etiology in nontraumatic spinal cord injury, tetraplegia and incomplete injuries occurred more than paraplegia and complete injuries, indwelling catheter was the most common voiding method, and the duration of hospitalization decreased. CONCLUSION: Many trends changed in epidemiology of spinal cord injury.

Depression and Quality of Life in Patients within the First 6 Months after the Spinal Cord Injury.

OBJECTIVE: To evaluate the severity of depression, degree of life satisfaction, level of stress, and resilience among patients in the first 6 months after a spinal cord injury (SCI). METHOD: 36 patients with SCI were asked to fill out questionnaires concerning Beck Depression Inventory (BDI), World Health Organization Quality of Life Questionnaire-BREF, Stress Response Inventory, and Connor-Davidson resilience scale. All patients had experienced an SCI within the last 6 months before the commencement of this study. RESULTS: In our study, the patients who experienced the SCI within the last six months had a higher rate of depression (63.9%) and a higher overall level of depression (13.8 points). The unmarried group had a significantly higher quality of life (QOL; p<0.05) when compared with the married group. In the motor complete group, severity of depression and level of stress were higher, whereas QOL was lower than the motor incomplete group (p<0.05). The mean American Spinal Injury Association (ASIA) Motor Score (AMS) was much higher in the non-depressive group (p<0.05) when compared with the depressive group. CONCLUSION: We found the patients within six months after SCI injury had higher rate of depression and higher overall level of depression. Also, patients with motor complete injury had affected significantly on depression, QOL and stress. We found the married patients had poorer QOL and depressive group had lower AMS score of lower extremity. Therefore, there should be emphasis of psychological care who have motor complete injury and are married during the early stage.