Immune Regulation and Immune Therapy in Melanoma: Review with Emphasis on CD155 Signalling.

Melanoma is commonly diagnosed in a younger population than most other solid malignancies and, in Australia and most of the world, is the leading cause of skin-cancer-related death. Melanoma is a cancer type with high immunogenicity; thus, immunotherapies are used as first-line treatment for advanced melanoma patients. Although immunotherapies are working well, not all the patients are benefitting from them. A lack of a comprehensive understanding of immune regulation in the melanoma tumour microenvironment is a major challenge of patient stratification. Overexpression of CD155 has been reported as a key factor in melanoma immune regulation for the development of therapy resistance. A more thorough understanding of the actions of current immunotherapy strategies, their effects on immune cell subsets, and the roles that CD155 plays are essential for a rational design of novel targets of anti-cancer immunotherapies. In this review, we comprehensively discuss current anti-melanoma immunotherapy strategies and the immune response contribution of different cell lineages, including tumour endothelial cells, myeloid-derived suppressor cells, cytotoxic T cells, cancer-associated fibroblast, and nature killer cells. Finally, we explore the impact of CD155 and its receptors DNAM-1, TIGIT, and CD96 on immune cells, especially in the context of the melanoma tumour microenvironment and anti-cancer immunotherapies.

Prevalence and prognosis of acute pancreatitis in critically ill patients with COVID-19.

BACKGROUND: Coronavirus disease 2019 (COVID-19) is a global pandemic issue. In addition to the well-known respiratory and fever symptoms, gastrointestinal symptoms have also been reported. This study aimed to evaluate the prevalence and prognosis of patients with COVID-19 infection complicated with acute pancreatitis in intensive care unit (ICU). METHODS: This was a retrospective observational cohort study, and patients aged 18 years or older, admitted into the ICU in a single tertiary center from January 1, 2020, to April 30, 2022 were enrolled. Patients were identified by electronic medical records and reviewed manually. The primary outcome was the prevalence of acute pancreatitis among ICU patients with COVID-19. The secondary outcomes were the length of hospital stay, need for mechanical ventilation (MV), need for continuous renal replacement therapy (CRRT), and in-hospital mortality. RESULTS: A total of 4133 patients, admitted into the ICU, were screened. Among these patients, 389 were infected by COVID-19, and 86 were diagnosed with acute pancreatitis. COVID-19 positive patients were more likely to present with acute pancreatitis than COVID-19 negative patients (odds ratio = 5.42, 95% confidence interval: 2.35-6.58, P < 0.01). However, the length of hospital stay, need for MV, need for CRRT, and in-hospital mortality were not significantly different between acute pancreatitis patients with and without COVID-19 infection. CONCLUSIONS: Severe COVID-19 infections may cause acute pancreas damage in critically ill patients. However, the prognosis may not differ between acute pancreatitis patients with and without COVID-19 infection.

Threonyl-tRNA Synthetase Promotes T Helper Type 1 Cell Responses by Inducing Dendritic Cell Maturation and IL-12 Production via an NF-κB Pathway.

Threonyl-tRNA synthetase (TRS) is an aminoacyl-tRNA synthetase that catalyzes the aminoacylation of tRNA by transferring threonine. In addition to an essential role in translation, TRS was extracellularly detected in autoimmune diseases and also exhibited pro-angiogenetic activity. TRS is reported to be secreted into the extracellular space when vascular endothelial cells encounter tumor necrosis factor-α. As T helper (Th) type 1 response and IFN-γ levels are associated with autoimmunity and angiogenesis, in this study, we investigated the effects of TRS on dendritic cell (DC) activation and CD4 T cell polarization. TRS-treated DCs exhibited up-regulated expression of activation-related cell-surface molecules, including CD40, CD80, CD86, and MHC class II. Treatment of DCs with TRS resulted in a significant increase of IL-12 production. TRS triggered nuclear translocation of the NF-κB p65 subunit along with the degradation of IκB proteins and the phosphorylation of MAPKs in DCs. Additionally, MAPK inhibitors markedly recovered the degradation of IκB proteins and the increased IL-12 production in TRS-treated DCs, suggesting the involvement of MAPKs as the upstream regulators of NF-κB in TRS-induced DC maturation and activation. Importantly, TRS-stimulated DCs significantly increased the populations of IFN-γ+CD4 T cells, and the levels of IFN-γ when co-cultured with CD4+ T cells. The addition of a neutralizing anti-IL-12 mAb to the cell cultures of TRS-treated DCs and CD4+ T cells resulted in decreased IFN-γ production, indicating that TRS-stimulated DCs may enhance the Th1 response through DC-derived IL-12. Injection of OT-II mice with OVA-pulsed, TRS-treated DCs also enhanced Ag-specific Th1 responses in vivo. Importantly, injection with TRS-treated DC exhibited increased populations of IFN-γ+-CD4+ and -CD8+ T cells as well as secretion level of IFN-γ, resulting in viral clearance and increased survival periods in mice infected with influenza A virus (IAV), as the Th1 response is associated with the enhanced cellular immunity, including anti-viral activity. Taken together, these results indicate that TRS promotes the maturation and activation of DCs, DC-mediated Th1 responses, and anti-viral effect on IAV infection.

IL-33 changes CD25hi Tregs to Th17 cells through a dendritic cell-mediated pathway.

Interleukin (IL)-33 is an alarmin factor that is highly secreted in a variety of autoimmune diseases, induces maturation of dendritic cells (DCs) and differentiation of T helper 17 (Th17) cells. As the balance between Th17 cells and regulatory T cells (Tregs) is important to maintain immune homeostasis, in this study, we investigated the effects of IL-33 on Treg cell response. We observed that direct treatment with IL-33 had no effect on Treg differentiation, whereas IL-33-matured DCs (IL33-matDCs) inhibited the differentiation of CD4+ T cells to Tregs by decreasing the expression of Foxp3. Furthermore, co-culture with IL-33-matDCs changed stable Tregs (CD25hiCD4+ Tregs) to IL-17-producing cells, whereas IL-33-matDCs had little effects on unstable Tregs (CD25loCD4+ Tregs). The stable Tregs were demonstrated to express high levels of IL-6 receptors. Blocking of IL-6 secreted from IL-33-matDCs suppressed the conversion of Tregs to Th17 cells, indicating the greater propensity to convert stable Tregs to Th17 cells is due to IL-6 signaling. Taken together, these results demonstrate that IL-33 inhibits Treg differentiation and the conversion of stable Tregs to Th17 cells via DCs.

Differential effects of luteolin and its glycosides on invasion and apoptosis in MDA-MB-231 triple-negative breast cancer cells.

Luteolin is known to have anticancer activity in various cancers. Recent studies have shown that luteolin glycosides, such as luteolin-8-C-ß-fucopyranoside, 7-methoxy-luteolin-8-C-ß-(6- deoxyxylopyranos-3-uloside) and luteolin-8-C-ß-d-glucopyranoside, flavonoids that are present in Arthraxon hispidus, exert antimigratory and anti-invasive effects, but no cytotoxic effect in estrogen receptor-positive MCF7 breast cancer cells. In the present study, we further investigated and compared differential effects of luteolin and its glycosides in MDA-MB-231 triple-negative breast cancer cells. Luteolin suppressed the expression of matrix metalloproteinase-9 and inhibited migration and invasion in MDA-MB-231 cells treated with the tumor promotor 12-O-tetradecanoylphorbol-13-acetate at non-cytotoxic concentrations (0, 5, and 10 µM). Furthermore, at cytotoxic concentrations (20 and 40 µM), luteolin induced apoptosis via extrinsic and intrinsic pathways in MDA-MB-231 cells. However, luteolin glycosides did not exert any cytotoxic, antimigratory, or anti-invasive effect in MDA-MB-231 cells. In brief, luteolin had both antimetastatic and cytotoxic effects on MDA-MB-231 cells, whereas luteolin glycosides had no effect on this cell line. Taking together the present results and our previous findings on the differential effects of luteolin and its glycosides on MDA-MB-231 and MCF-7 breast cancer cells, luteolin and its glycosides can be suggested as a potential candidate for breast cancer therapy.

NLRP3 negatively regulates Treg differentiation through Kpna2-mediated nuclear translocation.

Naïve CD4+ T cells in the periphery differentiate into regulatory T cells (Tregs) in which Foxp3 is expressed for their suppressive function. NLRP3, a pro-inflammatory molecule, is known to be involved in inflammasome activation associated with several diseases. Recently, the expression of NLRP3 in CD4+ T cells, as well as in myeloid cells, has been described; however, a role of T cell-intrinsic NLRP3 in Treg differentiation remains unknown. Here, we report that NLRP3 impeded the expression of Foxp3 independent of inflammasome activation in Tregs. NLRP3-deficient mice elevate Treg generation in various organs in the de novo pathway. NLRP3 deficiency increased the amount and suppressive activity of Treg populations, whereas NLRP3 overexpression reduced Foxp3 expression and Treg abundance. Importantly, NLRP3 interacted with Kpna2 and translocated to the nucleus from the cytoplasm under Treg-polarizing conditions. Taken together, our results identify a novel role for NLRP3 as a new negative regulator of Treg differentiation, mediated via its interaction with Kpna2 for nuclear translocation.

Hybrid Beamforming for Reduction of Inter-Beam Interference in Millimeter-Wave Cellular Systems.

In millimeter-wave (mm-wave) cellular systems, beamforming antennas are necessary at both the base station (BS) and mobile station (MS) to compensate for high attenuation in mm-wave frequency bands and to extend the transmission range. The beamforming antennas also allow each BS to serve a number of MSs simultaneously, providing a substantial gain in system capacity. In space-division multiple access (SDMA) systems, the challenge is the inter-beam interference (IBI) caused by adjacent beams that are formed by the BS in the same cell and BSs in neighboring cells. The beams that are formed toward MSs in each cell may generate significant interference to MSs in neighboring cells, especially for MSs at the cell boundary. In this paper, we propose four different digital precoding techniques (Type-1, Type-2, Type-3, and Type-4) to reduce IBI in mm-wave cellular systems with a hybrid beamformer. Simulation results show that the proposed techniques can reduce the IBI in mm-wave cellular systems effectively, compared with a single-cell multiuser case.

IL-33-matured dendritic cells promote Th17 cell responses via IL-1ß and IL-6.

IL-33 is associated with a variety of autoimmune diseases, such as sclerosis, inflammatory bowel disease, and rheumatoid arthritis. Although IL-33 is mainly involved in the induction of Th2 cells, however, the relationship between IL-33 and Th17 cells is still largely unknown. In this study, we investigated the effects of IL-33 on DC-mediated CD4+ T cell activation and Th17 cell differentiation because DCs are essential cells for presenting self-antigens to CD4+ T cells in autoimmune disease conditions. OT-II mice were injected with IL-33-treated DCs or untreated DCs that were primed by OVA323-339 peptide, and their Th17 cell responses were compared. Th17 cell population and IL-17 expression levels were significantly increased in draining lymph nodes of mice injected with IL-33-treated DCs, compared with those in mice injected with untreated DCs. IL-33 treatment maturated DCs to present self-antigens and to increase production of proinflammatory cytokines such as IL-1ß and IL-6, which have a crucial role in Th17 cell differentiation. We found that the IL-33-matured DCs enhanced the expression of an early T cell activation marker (CD69) and the Th17 master transcription factor (RORγt), but IL-33 did not directly affect CD4+ T cell differentiation or increase Th17 polarization. Notably, neutralizing IL-1ß and/or IL-6 significantly decreased IL-17 expression levels and Th17 cell population which were increased by the coculture of CD4+ T cells with IL-33-matured DCs, indicating that IL-33 may induce Th17 cell responses via IL-1ß and IL-6 derived from IL-33-matured DCs.

l-Asparaginase-mediated downregulation of c-Myc promotes 1,25(OH)2 D3 -induced myeloid differentiation in acute myeloid leukemia cells.

Treatment of acute myeloid leukemia (AML) largely depends on chemotherapy, but current regimens have been unsatisfactory for long-term remission. Although differentiation induction therapy utilizing 1,25(OH)2 D3 (VD3) has shown great promise for the improvement of AML treatment efficacy, severe side effects caused by its supraphysiological dose limit its clinical application. Here we investigated the combinatorial effect of l-asparaginase (ASNase)-mediated amino acid depletion and the latent alternation of VD3 activity on the induction of myeloid differentiation. ASNase treatment enhanced VD3-driven phenotypic and functional differentiation of three-different AML cell lines into monocyte/macrophages, along with c-Myc downregulation. Using gene silencing with shRNA and a chemical blocker, we found that reduced c-Myc is a critical factor for improving VD3 efficacy. c-Myc-dependent inhibition of mTORC1 signaling and induction of autophagy were involved in the enhanced AML cell differentiation. In addition, in a postculture of AML cells after each treatment, ASNase supports the antileukemic effect of VD3 by inhibiting cell growth and inducing apoptosis. Finally, we confirmed that the administration of ASNase significantly improved VD3 efficacy in the prolongation of survival time in mice bearing tumor xenograft. Our results are the first to demonstrate the extended application of ASNase, which is currently used for acute lymphoid leukemia, in VD3-mediated differentiation induction therapy for AML, and suggest that this drug combination may be a promising novel strategy for curing AML.

Costunolide, a sesquiterpene lactone, inhibits the differentiation of pro-inflammatory CD4+ T cells through the modulation of mitogen-activated protein kinases.

CD4+ T cell activation and adequate differentiation into effector T helper (Th) cells are crucial for mediating adaptive immune responses to cope with foreign pathogens. Despite the significant role of Th cells, excessive increases in their numbers result in inflammatory and autoimmune diseases. In this study, we investigated the effects of costunolide, a plant-derived natural compound with an anti-inflammatory activity, in regulating Th cells and the underlying mechanisms. Costunolide significantly decreased cell populations of differentiated Th1, Th2, and Th17 subsets under Th subset-polarizing conditions, while exerting statistically negligible effects on Treg cell differentiation. Furthermore, costunolide inhibited the expression level of Th subset-polarizing master genes such as T-bet, GATA3, and RORγt, indicating that costunolide inhibits the differentiation of CD4+ T cells into Th subsets. Additionally, costunolide suppressed the proliferative activity of CD4+ T cells and the expression of CD69 activation marker on CD4+ T cells. When the molecular targets of costunolide were investigated, phosphorylation of ERK and p38 was found to be decreased under Th subset-polarizing conditions, whereas activity of JNK remained unchanged. U0126, an ERK inhibitor, and SB203580, a p38 inhibitor, decreased the expression of CD69 upon TCR stimulation and inhibited CD4+ T cell differentiation, indicating that both ERK and p38 are suggested to be critical molecular targets of costunolide. Taken together, these results suggest that costunolide inhibits the differentiation of CD4+ T cells by suppressing ERK and p38 activities and can be an effective therapeutic agent for T cell-mediated immune diseases.

5-diphenylacetamido-indirubin-3'-oxime as a novel mitochondria-targeting agent with anti-leukemic activities.

Current treatment for leukemia largely depends on chemotherapy. Despite the progress in treatment efficacy of chemotherapy, a poor outcome consequent upon chemoresistance against conventional anti-cancer drugs still remains to be solved. In this study, we report 5-diphenylacetamido-indirubin-3'-oxime (LDD398) as a novel mitochondria-targeting anti-leukemic agent, which is a derivative of indirubin used in traditional medicine. Treatment with LDD398 resulted in caspase activation, cell death, and growth arrest at G2/M phases in leukemia cells. Interestingly, LDD398 quickly collapsed mitochondrial membrane potential (MMP) within 1 h, accompanied by cytochrome c release into cytosol and severe depletion of cellular ATP. However, the LDD398-induced cellular events was significantly mitigated by blockage of mitochondrial permeability transition pore (MPTP) opening with chemical and genetic modifications, strongly supporting that LDD398 executes its anti-leukemic activity via an inappropriate opening of MPTP and a consequent depletion of ATP. The most meaningful finding was the prominent effectiveness of LDD398 on primary leukemia cells and also on malignant leukemia cells resistant to anticancer drugs. Our results demonstrate that, among a series of indirubin derivatives, LDD398 induces leukemia cell death via a different mode from indirubin or conventional chemotherapeutics, and can be employed as a potent anti-cancer agent in the treatment for newly diagnosed and relapsed leukemia.

Luteolin induces cell cycle arrest and apoptosis through extrinsic and intrinsic signaling pathways in MCF-7 breast cancer cells.

Luteolin is a common flavonoid that exists in medicinal herbs, fruits, and vegetables. Luteolin has biochemical functions including anti-allergy, anti-inflammation, and anti-cancer functions. However, its efficacy and precise mode of action against breast cancer are still under study. To elucidate whether luteolin exhibits an anticancer effect in breast cancer, MCF-7 breast cancer cells were incubated with luteolin, and apoptosis was assessed by observing nuclear morphological changes and by performing cell viability assay, cell cycle analysis, annexin V-FITC/PI double staining, western blotting, RT-PCR, and mitochondrial membrane potential measurements. Luteolin inhibited growth through perturbation of cell cycle progression at the sub-G1 and G1 phases in MCF-7 cells. Furthermore, luteolin enhanced the expression of death receptors, such as DR5, and activated caspase cascades. It enhanced the activities of caspase-8/-9/-3 in a dose-dependent manner, followed by inactivation of PARP. Activation of caspase-8 and caspase-9 induced caspase-3 activity, respectively, in apoptosis of extrinsic and intrinsic pathways. Luteolin also induced mitochondrial membrane potential collapse and cytochrome c release, and increased Bax expression by inhibiting expression of Bcl-2. Taken together, these results suggest that luteolin provokes cell cycle arrest and induces apoptosis by activating the extrinsic and intrinsic pathways.

Luteolin induces intrinsic apoptosis via inhibition of E6/E7 oncogenes and activation of extrinsic and intrinsic signaling pathways in HPV-18-associated cells.

Luteolin, a flavonoid extracted from a number of plants with recognized anticancer, anti-inflammatory and anti-oxidative activities, inhibits angiogenic processes and modulates multidrug resistance. However, the efficacy and mechanisms of action of this flavonoid agent are still undergoing study. In order to elucidate whether luteolin exhibits an anticancer effect in cervical cancer cells, HeLa cells were incubated with luteolin and apoptosis was assessed by observing nuclear morphological changes, and performing Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) staining. Cell cycle analysis, western blotting, RT-PCR and mitochondrial membrane potential measurements were also carried out. Luteolin showed a significant dose-dependent cytotoxic effect only in human papillomavirus (HPV)-positive cervical cancer cells, when compared to its effect on HPV-negative cervical cancer C33A cells. Expression levels of human papilloma virus E6 and E7 oncogenes were suppressed, those of related factors pRb and p53 were recovered and E2F5 was increased by luteolin treatment. Furthermore, luteolin enhanced the expression of death receptors and death receptor downstream factors such as Fas/FasL, DR5/TRAIL and FADD in HeLa cells, and activated caspase cascades. In particular, luteolin enhanced the activity of caspase-3 and -8 in a dose-dependent manner. Activation of caspase-3 induced caspase-8 activity and vice versa. Luteolin also induced mitochondrial membrane potential collapse and cytochrome c release, and inhibited Bcl-2 and Bcl-xL expression. In conclusion, luteolin exerts anticarcinogenic activity through inhibition of E6 and E7 expression and cross-activation of caspase-3 and -8. Taken together, these results suggest that luteolin induces inactivation of HPV-18 oncogene expression and apoptosis by activating the intrinsic and extrinsic pathways.

Interaction network mapping among IL-32 isoforms.

IL-32 has been studied for its pleiotropic effects ranging from host immune responses to cell differentiation. Although several IL-32 isoforms have been characterized for their effects on cells, the roles of the others remain unclear. We previously reported that IL-32δ interacted with IL-32ß and inhibited IL-32ß-mediated IL-10 production. Thus, we performed comprehensive analyses to reveal more interactions between IL-32 isoforms in this study. We screened the interactions of 81 combinations of nine IL-32 isoforms by using a yeast two-hybrid assay, which identified 13 heterodimeric interactions. We verified these results by using reciprocal immunoprecipitation assays and reconfirmed 10 interactions, and presented the interaction network map between IL-32 isoforms. Our data suggest that IL-32 may have diverse intracellular effects through the interactions with its different isoforms.

Colorectal cancer screening in Korean workers: using a stage model approach to examine the ecological predictors of behavior.

BACKGROUND: Early detection is important for reducing mortality by colorectal cancer. Workplaces have access to a large number of people, approximately half of the Korean population. For cancer prevention, it is necessary to approach cancer screening through the workplace. OBJECTIVE: In this cross-sectional study, we aimed to identify colorectal cancer screening (CRCS) stages and to predict factors that affect the respective stages. METHODS: Data were collected from 314 manual workers at 32 medium-sized and small workplaces located in Korea. The dependent variable was the stage of CRCS, and independent variables were intrapersonal, interpersonal, and organizational levels. RESULTS: At the intrapersonal level, workers who increased work hours per week or who felt stress were less likely to be in the acting/maintenance stage than in the decided to act stage of CRCS. At the organizational level, workers in medium-sized workplaces, those whose administrators secured health checkup and cancer screening budget for their workplace, and those considering health checkup and cancer screening were more likely to be in the acting/maintenance stage, compared with the decided to act stage. CONCLUSIONS: Our findings suggest that the respective stages are affected by different intrapersonal, interpersonal, and organizational factors. IMPLICATION FOR PRACTICE: The workplace environment and organizational predictors before the implementation of CRCS promotion programs may produce better results.

Luteolin 8-C-ß-fucopyranoside inhibits invasion and suppresses TPA-induced MMP-9 and IL-8 via ERK/AP-1 and ERK/NF-κB signaling in MCF-7 breast cancer cells.

Matrix metalloproteinase 9 (MMP-9) and interleukin-8 (IL-8) play major roles in tumor progression and invasion of breast cancer cells. The present study was undertaken to investigate the inhibitory mechanism of cell invasion by luteolin 8-C-ß-fucopyranoside (named as LU8C-FP), a C-glycosylflavone, in human breast cancer cells. We investigated whether LU8C-FP would inhibit MMP-9 activation and IL-8 expression in 12-O-tetradecanoylphorbol-13-acetate (TPA)-treated MCF-7 breast cancer cells. LU8C-FP suppressed TPA-induced MMP-9 and IL-8 secretion and mRNA expression via inhibition of the MAPK signaling pathway and down-regulation of nuclear AP-1 and NF-κB. TPA-induced phosphorylation of ERK 1/2 was suppressed by LU8C-FP, whereas JNK and p38 MAPK phosphorylation were unaffected. In addition, LU8C-FP blocked the ERK 1/2 pathways following expression of MMP-9 and IL-8. These results suggest LU8C-FP may function to suppress invasion of breast cancer cells through the ERK/AP-1 and ERK/NF-κB signaling cascades.

Factors associated with needlestick and sharp injuries among hospital nurses: a cross-sectional questionnaire survey.

BACKGROUND: The current status of needlestick or sharp injuries of hospital nurses and factors associated with the injuries have not been systematically examined with representative registered nurse samples in South Korea. OBJECTIVE: To examine the incidence to needlestick or sharp injuries and identify the factors associated with such injuries among hospital nurses in South Korea. DESIGN, SETTINGS AND PARTICIPANTS: A cross-sectional survey of hospital nurses in South Korea. Data were collected from 3079 registered nurses in 60 acute hospitals in South Korea by a stratified random sampling method based on the region and number of beds. METHODS: The dependent variable was the occurrence of needlestick or sharp injuries in the last year, and the independent variables were protective equipment, nurse characteristics, and hospital characteristics. This study employed logistic regression analysis with generalized estimating equation clustering by hospital to identify the factors associated with needlestick or sharp injuries. RESULTS: The majority (70.4%) of the hospital nurses had experienced needlestick or sharp injuries in the previous year. The non-use of safety containers for disposal of sharps and needles, less working experience as a registered nurse, poor work environments in regards to staffing and resource adequacy, and high emotional exhaustion significantly increased risk for needlestick or sharp injuries. Working in perioperative units also significantly increased the risk for such injuries but working in intensive care units, psychiatry, and obstetrics wards showed a significantly lower risk than medical-surgical wards. CONCLUSIONS: The occurrence of needlestick or sharp injuries of registered nurses was associated with organizational characteristics as well as protective equipment and nurse characteristics. Hospitals can prevent or reduce such injuries by establishing better work environments in terms of staffing and resource adequacy, minimizing emotional exhaustion, and retaining more experienced nurses. All hospitals should make safety-engineered equipment available to registered nurses. Hospitals as well as specific units showing higher risk for needlestick and sharp injuries should implement organizational strategies to prevent such injuries. It is also necessary to establish a monitoring system of needlestick and sharp injuries at a hospital level and a reporting system at the national level in South Korea.

Interleukin-32δ interacts with IL-32ß and inhibits IL-32ß-mediated IL-10 production.

There is growing evidence for multifunctional properties of IL-32. We previously demonstrated that IL-32ß upregulates IL-10 production through the association with PKCδ. In this study, we examined the effects of other IL-32 isoforms on IL-10 production. We found that IL-32δ decreased IL-10 production and investigated the inhibitory mechanism of IL-32δ. We showed that IL-32δ suppressed IL-32ß binding to PKCδ by interacting with IL-32ß. The inhibitory effect of IL-32δ on IL-32ß association with PKCδ was further verified by immuno-fluorescence staining. The co-localization of IL-32ß and PKCδ around the nuclear membrane was disrupted by IL-32δ. Our data therefore indicate that IL-32δ plays an inhibitory role against IL-32ß function, which also suggests that IL-32 may be regulated by its own isoform.

Interleukin-32δ interacts with IL-32ß and inhibits IL-32ß-mediated IL-10 production.

There is growing evidence for multifunctional properties of IL-32. We previously demonstrated that IL-32ß upregulates IL-10 production through the association with PKCδ. In this study, we examined the effects of other IL-32 isoforms on IL-10 production. We found that IL-32δ decreased IL-10 production and investigated the inhibitory mechanism of IL-32δ. We showed that IL-32δ suppressed IL-32ß binding to PKCδ by interacting with IL-32ß. The inhibitory effect of IL-32δ on IL-32ß association with PKCδ was further verified by immuno-fluorescence staining. The co-localization of IL-32ß and PKCδ around the nuclear membrane was disrupted by IL-32δ. Our data therefore indicate that IL-32δ plays an inhibitory role against IL-32ß function, which also suggests that IL-32 may be regulated by its own isoform.

MMHD [(S,E)-2-methyl-1-(2-methylthiazol-4-yl) hexa-1,5-dien-ol], a novel synthetic compound derived from epothilone, suppresses nuclear factor-kappaB-mediated cytokine expression in lipopolysaccharide-stimulated BV-2 microglia.

The effects of MMHD [(S,E)-2-methyl-1-(2-methylthiazol-4-yl) hexa-1,5-dien-ol], a novel synthetic compound derived from epothilone, was investigated for its effects on the expression of proinflammatory mediators in lipopolysaccharide-stimulated BV-2 microglia. MMHD attenuated the expressions of inducible nitric oxide synthase and cyclooxygenase-2 mRNA and protein without affecting cell viability. Moreover, MMHD suppressed nuclear factor-kappaB (NF-kappaB) activation via the translocation of p65 into the nucleus. These results indicate that MMHD exerts anti-inflammatory properties by suppressing the transcription of proinflammatory cytokine genes through the NF-kappaB signaling pathway.