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Abstract Cerium oxide (CeO2) nanospheres have limited enzymatic activity that hinders further application in catalytic therapy, but they have an “oxidation switch” to enhance their catalytic activity by increasing oxygen vacancies. In this study, according to the defect-engineering strategy, we developed PtCuOX/CeO2-X nanozymes as highly efficient SOD/CAT mimics by introducing bimetallic copper (Cu) and platinum (Pt) into CeO2 nanospheres to enhance the oxygen vacancies, in an attempt to combine near-infrared (NIR) irradiation to regulate microenvironment for osteoarthritis (OA) therapy. As expected, the Cu and Pt increased the Ce3+/Ce4+ ratio of CeO2 to significantly enhance the oxygen vacancies, and simultaneously CeO2 (111) facilitated the uniform dispersion of Cu and Pt. The strong metal-carrier interaction synergy endowed the PtCuOX/CeO2-X nanozymes with highly efficient SOD/CAT-like activity by the decreased formation energy of oxygen vacancy, promoted electron transfer, the increased adsorption energy of intermediates, and the decreased reaction activation energy. Besides, the nanozymes have excellent photothermal conversion efficiency (55.41%). Further, the PtCuOX/CeO2-X antioxidant system effectively scavenged intracellular ROS and RNS, protected mitochondrial function, and inhibited the inflammatory factors, thus reducing chondrocyte apoptosis. In vivo, experiments demonstrated the biosafety of PtCuOX/CeO2-X and its potent effect on OA suppression. In particular, NIR radiation further enhanced the effects. Mechanistically, PtCuOX/CeO2-X nanozymes reduced ras-related C3 botulinum toxin substrate 1 (Rac-1) and p-p65 protein expression, as well as ROS levels to remodel the inflammatory microenvironment by inhibiting the ROS/Rac-1/nuclear factor kappa-B (NF-κB) signaling pathway. This study introduces new clinical concepts and perspectives that can be applied to inflammatory diseases. Graphical Abstract

Abstract Constant-frequency ultrasonic treatment helped to improve seed germination. However, variable-frequency ultrasonic treatment on maize seed germination were rarely reported. In this study, maize seeds were exposed to 20–40 kHz ultrasonic for 40 s. The germination percentage and radicle length of maize seeds increased by 10.4% and 230.5%. Ultrasonic treatment also significantly increased the acid protease, α-amylase, and β-amylase contents by 96.4%, 73.8%, and 49.1%, respectively. Transcriptome analysis showed that 11,475 differentially expressed genes (DEGs) were found in the ultrasonic treatment and control groups, including 5,695 upregulated and 5,780 downregulated. Metabolic pathways and transcription factors (TFs) were significantly enriched among DEGs after ultrasonic treatment. This included metabolism and genetic information processing, that is, ribosome, proteasome, and pyruvate metabolism, sesquiterpenoid, triterpenoid, and phenylpropanoid biosynthesis, and oxidative phosphorylation, as well as transcription factors in the NAC, MYB, bHLH, WRKY, AP2, bZIP, and ARF families. Variable-frequency ultrasonic treatment increased auxin, gibberellin, and salicylic acid by 5.5%, 37.3%, and 28.9%, respectively. Abscisic acid significantly decreased by 33.2%. The related DEGs were upregulated and downregulated to varying degrees. Seed germination under the abiotic stress conditions of salt stress (NaCl solution), drought (PEG solution), and waterlogging (water-saturated sand bed) under ultrasonic treatment were promoted, radicle length was significantly increased by 30.2%, 30.5%, and 27.3%, respectively; and germination percentage by 14.8%, 20.1%, and 21.6%, respectively. These findings provide new insight into the mechanisms through ultrasonic to promote maize seed germination.

Abstract Intra-articular drugs used to treat osteoarthritis (OA) often suffer from poor pharmacokinetics and stability. Nano-platforms as drug delivery systems for drug delivery are promising for OA therapy. In this study, we reported an M1 macrophage-targeted delivery system Bai@FA-UIO-66-NH2 based on folic acid (FA) -modified metal-organic framework (MOF) loaded with baicalin (Bai) as antioxidant agent for OA therapy. With outstanding biocompatibility and high drug loading efficiency, Bai@FA-UIO-66-NH2 could be specifically uptaken by LPS-induced macrophages to serve as a potent ROS scavenger, gradually releasing Bai at the subcellular level to reduce ROS production, modulate macrophage polarization to M2, leading to alleviation of synovial inflammation in OA joints. The synergistic effect of Bai@FA-UIO-66-NH2 on macrophage polarization and ROS scavenging significantly improved the therapeutic efficacy of OA, which may provide a new insight into the design of OA precision therapy.

Ferroptosis, a defensive strategy commonly employed by the host cells to restrict pathogenic infections, has been implicated in the development and therapeutic responses of various types of cancer. However, the role of ferroptosis in oncogenic Kaposi's sarcoma-associated herpesvirus (KSHV)-induced cancers remains elusive. While a growing number of non-histone proteins have been identified as acetylation targets, the functions of these modifications have yet to be revealed. Here, we show KSHV reprogramming of host acetylation proteomics following cellular transformation of rat primary mesenchymal precursor. Among them, SERPINE1 mRNA binding protein 1 (SERBP1) deacetylation is increased and required for KSHV-induced cellular transformation. Mechanistically, KSHV-encoded viral interleukin-6 (vIL-6) promotes SIRT3 deacetylation of SERBP1, preventing its binding to and protection of lipoyltransferase 2 (Lipt2) mRNA from mRNA degradation resulting in ferroptosis. Consequently, a SIRT3-specific inhibitor, 3-TYP, suppresses KSHV-induced cellular transformation by inducing ferroptosis. Our findings unveil novel roles of vIL-6 and SERBP1 deacetylation in regulating ferroptosis and KSHV-induced cellular transformation, and establish the vIL-6-SIRT3-SERBP1-ferroptosis pathways as a potential new therapeutic target for KSHV-associated cancers.

Abstract N-acetyltransferase 10 (NAT10) is an N 4‐acetylcytidine (ac4C) writer that catalyzes RNA acetylation at cytidine N4 position on tRNAs, rRNAs and mRNAs. Recently, NAT10 and the associated ac4C have been reported to increase the stability of HIV-1 transcripts. Here, we show that NAT10 catalyzes ac4C addition to the polyadenylated nuclear RNA (PAN), a long non-coding RNA encoded by the oncogenic DNA virus Kaposi’s sarcoma-associated herpesvirus (KSHV), triggering viral lytic reactivation from latency. Mutagenesis of ac4C sites in PAN RNA in the context of KSHV infection abolishes PAN ac4C modifications, downregulates the expression of viral lytic genes and reduces virion production. NAT10 knockdown or mutagenesis erases ac4C modifications of PAN RNA and increases its instability, and prevents KSHV reactivation. Furthermore, PAN ac4C modification promotes NAT10 recruitment of IFN-γ-inducible protein-16 (IFI16) mRNA, resulting in its ac4C acetylation, mRNA stability and translation, and eventual inflammasome activation. These results reveal a novel mechanism of viral and host ac4C modifications and the associated complexes as a critical switch of KSHV replication and antiviral immunity.

Effective phosphorus (P) management is crucial for optimal blueberry production. However, a comprehensive understanding of phosphorus distribution across soil depths and types after two decades of blueberry cultivation remains a challenge. This study examines pH, EC, SOC (soil organic carbon), Total N (total nitrogen), and phosphorus fractions in soils from Japanese blueberry fields that have been cultivated for over 20 years. The soils selected for this study represent typical soils from long-term blueberry-growing regions in Japan, ensuring the relevance of the findings to these key agricultural areas. Soil samples were gathered from depths of 0–30 cm and 30–60 cm, revealing significant variations in phosphorus content that are influenced by soil properties and fertilization history. Soil types such as KS (Kuroboku soils) and FS (Fluvic soils) show higher Total P accumulation in deeper layers, whereas BFS (Brown Forest soils) and RYS (Red-Yellow soils) accumulate more in shallower layers. Long-term cultivation has led to greater non-labile phosphorus (NLP) accumulation in shallower layers of KS, BFS, and FS soils, indicating strong phosphorus fixation. BFS soil also exhibits increased organic phosphorus (NaOH-Po) at deeper depths. NaOH-Po and NaHCO3-Po, through their interactions with EC and pH, critically modulate the transformation of NLP into labile phosphorus (LP), thereby influencing overall phosphorus and nitrogen dynamics in the soil. These findings underscore the importance of tailored phosphorus fertilization strategies based on blueberry field characteristics, providing a basis for low-input phosphorus fertilization approaches.

Articular cartilage regeneration is still a difficult task due to the cartilage’s weak capacity for self-healing and the effectiveness of the available therapies. The engineering of cartilage tissue has seen widespread use of stem cell-based therapies. However, efficient orientation of line-specific bone marrow mesenchymal stem cells (BMSCs) to chondrogenesis and maintenance of chondrogenic differentiation challenged stem cell-based therapy. Herein, we developed a Fe-based metal-organic framework (MOF) loaded with hematoporphyrin monomethyl ether (HMME) and cartilage-targeting arginine-aspartate-glycine (RGD) peptide to form MOF-HMME-RGD sonosensitizer to regulate BMSCs chondrogenic differentiation for cartilage regeneration via the modulation of reactive oxygen species (ROS). By using sonodynamic therapy (SDT), the MOF-HMME-RGD demonstrated favorable biocompatibility, could generate a modest amount of ROS, and enhanced BMSCs chondrogenic differentiation through increased accumulation of glycosaminoglycan, an ECM component specific to cartilage, and upregulated expression of key chondrogenic genes (ACAN, SOX9, and Col2a1). Further, transplanted BMSCs loading MOF-HMME-RGD combined with SDT enhanced cartilage regeneration for cartilage defect repair after 8 weeks into treatment. This synergistic strategy based on MOF nanoparticles provides an instructive approach to developing alternative sonosensitizers for cartilage regeneration combined with SDT.

Ethnopharmacological relevance: Pearl oyster (Pinctada martensii) is used in Chinese traditional medicine use in photoprotective, anti-inflammatory, and wound treatment.Aim of the study: This study explored whether the mucus protein of Pearl oyster (protein of Pinctada martensii, PMP) affects human skin fibroblast (HSF) proliferation, migration, collagen-related gene expression related to collagen formation, and in vivo healing effects. Materials and methods: The PMP component was analyzed by LC-MS/MS. The cell viability was evaluated using a CCK-8 kit. The expression genes were measured by reverse transcription polymerase chain reaction. A full-thickness excisional wounding model in Sprague-Dawley (SD) rats was used to test the repairing effect of PMP in vivo, and Hematoxylin-Eosin (H&E) and Masson's Trichrome staining were applied to evaluate skin structure. Results: The components of PMP were identified using LC-MS/MS proteomics, and a total of 3023 proteins were detected. The results of PMP-treated HSF showed that PMP effectively promoted cell proliferation by 1.6-fold and cell migration by 1.5-fold at a concentration of 1 mg/mL. Additionally, PMP treatment up-regulated the expression levels of collagen-related genes COL1A1, COL3A1, and MMP-1 in fibroblasts. Furthermore, PMP was applied in the therapy of full-thickness excisional wounds in rats. The results demonstrated that PMP significantly accelerated wound healing time, resulted in the recovery of dermal and epithelial thickness, and stimulated collagen regeneration. The regenerated skin closely resembled the structure of normal skin. Conclusions: These findings provide solid evidence supporting the potential of PMP as a promising candidate for the treatment of skin wounds.

Abstract A comprehensive modeling strategy for studying the thermomechanical tribological behaviors is proposed in this work. The wear degradation considering the influence of temperature (T) is predicted by Archard wear model with the help of the UMESHMOTION subroutine and arbitrary Lagrangian–Eulerian (ALE) remeshing technique. Adopting the proposed method, the thermomechanical tribological behaviors of railway vehicle disc brake system composed of forged steel brake disc and Cu-based powder metallurgy (PM) friction block are studied systematically. The effectiveness of the proposed methodology is validated by experimental test on a self-designed scaled brake test bench from the perspectives of interface temperature, wear degradation, friction noise and vibration, and contact status evolution. This work can provide an effective way for the investigation of thermomechanical tribological behaviors in the engineering field.

Post-translational modifications (PTMs) are essential for host antiviral immune response and viral immune evasion. Among a set of novel acylations, lysine propionylation (Kpr) has been detected in both histone and non-histone proteins. However, whether protein propionylation occurs in any viral proteins and whether such modifications regulate viral immune evasion remain elusive. Here, we show that Kaposi's sarcoma-associated herpesvirus (KSHV)-encoded viral interferon regulatory factor 1 (vIRF1) can be propionylated in lysine residues, which is required for effective inhibition of IFN-β production and antiviral signaling. Mechanistically, vIRF1 promotes its own propionylation by blocking SIRT6's interaction with ubiquitin-specific peptidase 10 (USP10) leading to its degradation via a ubiquitin-proteasome pathway. Furthermore, vIRF1 propionylation is required for its function to block IRF3-CBP/p300 recruitment and repress the STING DNA sensing pathway. A SIRT6-specific activator, UBCS039, rescues propionylated vIRF1-mediated repression of IFN-β signaling. These results reveal a novel mechanism of viral evasion of innate immunity through propionylation of a viral protein. The findings suggest that enzymes involved in viral propionylation could be potential targets for preventing viral infections.

Allicin, which is generated by the catalytic reaction between alliin and alliinase extracted from garlic, has been shown to have a wide range of antimicrobial activities, but its anti-Cryptococcus efficacy and mechanism are not quite clear. Here, we have determined that the Conversion rate of allicin in the reaction product reached 97.5%. The minimal inhibitory concentration (MIC) of allicin against Cryptococcus neoformans (C. neoformans) H99 was 2 μg/ml, which is comparable to fluconazole (FLU, 1 μg/ml). Furthermore, allicin exhibited effective antifungal activity against 46 clinical isolates of C. neoformans, and the MICs ranged from 1 to 8 μg/ml, even for AmB-insensitive strains. Interestingly, allicin also exerted additive or synergistic effects when combined with amphotericin B (AmB) and FLU. Time-killing curves and long-term live cell imaging of H99 showed that 4 MIC of allicin had fungicide activity. Additionally, allicin (4 and 8 mg/kg) exerted a dose-dependent therapeutic effect on H99-infected mice by significantly reducing the wet pulmonary coefficient and Cryptococcus load and reducing lung damage. Even the efficacy of 8 mg/kg was comparable to FLU (20 mg/kg). Transcriptomics revealed that allicin may act on the cell membrane of H99. Subsequently, transmission electron microscopy (TEM) observations showed that allicin clearly breached the cell membrane and organelles of H99. Confocal laser scanning microscopy (CLSM) results further confirmed that allicin disrupted the permeability of the cell membranes of H99 in a dose-dependent manner. Allicin exhibits strong anti-C. neoformans activity in vitro and in vivo, mainly by destroying the permeability and related functions of Cryptococcus cell membranes.

The multiaxial character of high-speed railway brake disc thermomechanical fatigue damage is studied in this work. Although the amplitudes and distributions of temperature, strain and stress are similar with uniform and rotating loading methods, the multiaxial behavior and out-of-phase failure status can only be revealed by the latter one. With the help of a multiaxial fatigue model, fatigue damage evaluation and fatigue life prediction are implemented, the contribution of a uniaxial fatigue parameter, multiaxial fatigue parameter and out-of-phase failure parameter to the total damage is discussed, and it is found that using the amplitude and distribution of temperature, stress and strain for fatigue evaluation will lead to an underestimation of brake disc thermomechanical fatigue damage. The results indicate that the brake disc thermomechanical fatigue damage belongs to a type of multiaxial fatigue. Using a uniaxial fatigue parameter causes around 14% underestimation of fatigue damage, while employing a multiaxial fatigue parameter without the consideration of out-of-phase failure will lead to an underestimation of about 5%. This work explains the importance of studying the thermomechanical fatigue damage of the brake disc from the perspective of multiaxial fatigue.

As part of the “generalized Nihewan Basin”, the Huailai basin has recently attracted archaeologists’ attention. Ten Paleolithic sites were found in this basin in 2014; among these, the Zhuwobu site is the oldest―dated to 504 ± 76 ka using the electron spin resonance (ESR) dating method. This study redated the Zhuwobu site using the multiple elevated temperatures (MET) post infrared (pIR) infrared stimulated luminescence (IRSL) procedure (MET-pIRIR) on both multi-grained single and multiple aliquots of potassium-rich feldspars (K-feldspars). The consistency of the De results obtained from the single- and multiple-aliquot procedures mutually supported the reliability of our age results. Our results suggest that the cultural layer at this site was deposited about 280 ± 13 ka (MIS 8) ago, ∼220 ka younger than the previous ESR age. Considering the region’s tectonic history and the characteristics of the sedimentary facies for the ZWB site, we suggested that the previous ESR age results for the bottom three samples from the sediment profile might be overestimated due to poor bleaching before burial. In contrast, the ESR age of 346 ± 32 ka (MIS 10) for one cultural-layer collected sample might be more reliable due to higher-quality bleaching before burial. Further archaeological, geological, and chronological studies are needed to explore the ancient hominins’ survival conditions in the “generalized Nihewan Basin” and possible connections with the renowned Zhoukoudian sites.

There is limited measure available to quantify the effect of polycarboxylate-ether based superplasticizer (PCE) on the microstructure of cement-based systems during the first 24 h. To fill this gap, the backscattered electron image analysis (BSE-IA) alongside the ternary technique is used in this study to separate composed phases quantitively and then calculate the average spacing between cement particles. Besides, together with an examination of hydration heat, the skeleton development of reaction products is investigated. The results show that cement hydration is not a constant process, and the developing mode for hydration products region varies with the particle size of cement. In this regard, numerous hydration products may gather around small cement particles and then adsorb other unhydrated particles, forming the continuous region. By contrast, the particles possessing relatively large size are surrounded by noticeable pores, which interrupt the continuity of the hydration products region. When introducing PCE, the agglomeration of cement particles and the average spacing between cement particles reduced, manifesting as an enlarged hydration products region alongside a decreased porosity at the area surrounding large particles. However, this leads to a decreased hydration degree for cement and extends the setting time of cement paste.

In this article, we analyze a second-order stochastic SEIR epidemic model with latent infectious and susceptible populations isolated at home. Firstly, by putting forward a novel inequality, we provide a criterion for the presence of an ergodic stationary distribution of the model. Secondly, we establish sufficient conditions for extinction. Thirdly, by solving the corresponding Fokker–Plank equation, we derive the probability density function around the quasi-endemic equilibrium of the stochastic model. Finally, by using the epidemic data of the corresponding deterministic model, two numerical tests are presented to illustrate the validity of the theoretical results. Our conclusions demonstrate that nations should persevere in their quarantine policies to curb viral transmission when the COVID-19 pandemic proceeds to spread internationally.

The effects of variations in the heat treatment process of milk on its quality and flavor are inevitable. This study investigated the effect of direct steam injection and instantaneous ultra-high-temperature (DSI-IUHT, 143 °C, 1–2 s) sterilization on the physicochemical properties, whey protein denaturation (WPD) rate, and volatile compounds (VCs) of milk. The experiment compared raw milk as a control with high-temperature short-time (HTST, 75 °C 15 s and 85 °C 15 s) pasteurization and indirect ultra-high-temperature (IND-UHT, 143 °C, 3–4 s) sterilization. The results showed no significant differences (p > 0.05) in physical stability between milk samples with different heat treatments. The DSI-IUHT and IND-UHT milks presented smaller particle sizes (p < 0.05) and more concentrated distributions than the HTST milk. The apparent viscosity of the DSI-IUHT milk was significantly higher than the other samples (p < 0.05) and is consistent with the microrheological results. The WPD of DSI-IUHT milk was 27.52% lower than that of IND-UHT milk. Solid-phase microextraction (SPME) and solvent-assisted flavor evaporation (SAFE) were combined with the WPD rates to analyze the VCs, which were positively correlated with ketones, acids, and esters and negatively associated with alcohols, heterocycles, sulfur, and aldehydes. The DSI-IUHT samples exhibited a higher similarity to raw and HTST milk than the IND-UHT samples. In summary, DSI-IUHT was more successful in preserving the milk’s quality due to its milder sterilization conditions compared to IND-UHT. This study provides excellent reference data for the application of DSI-IUHT treatment in milk processing.

ObjectiveThe limited information available on mixed mycosis involving the lungs makes the understanding of mixed fungal diseases insufficient and affects prognosis. Our study aims to improve understanding by exploring experience in the successful management of mixed fungal infections.MethodsPatients who had two types of mycosis involving the lung at the same disease course were retrospectively enrolled.ResultsBetween September 2011 and December 2019, 17 patients with proven mixed mycosis were enrolled. Four patients were immunocompromised, with one case each of lung transplantation, corticosteroid treatment, STAT3 hyper-IgE syndrome, and anti-IFN-γ autoantibody-associated immunodeficiency syndrome. Among 13 patients who were not immunocompromised, 9 had type 2 diabetes mellitus. Eight cases were coinfection with Mucor and Aspergillus, 4 cases were Cryptococcus and Aspergillus, 2 cases were Talaromyces marneffei and Cryptococcus, 2 cases were Talaromyces marneffei and Aspergillus, and 1 case was Candida and Aspergillus. Seven patients were diagnosed with mixed pulmonary mycosis at almost the same time. Among the remaining 10 patients, the initial treatment was ineffective in four cases, and six patients showed a partial response to the initial antifungal treatment, but the original fungal lesions became re-enlarged. Three patients were admitted to the intensive care unit during hospitalization, and one patient died. Another Mucor coinfection patient died due to treatment refusal.ConclusionMixed mycosis involving the lungs is not uncommon in patients without apparent immune deficiency diseases. During the management of mycosis, we recommend keeping mixed mycosis in mind for patients with a poor response to initial antifungal treatment, even in immunocompetent populations, and identifying the cause of illness through a rigorous procedure.

The article researches a stochastic hepatitis B epidemic model with saturated incidence rate, which is perturbed by both white noise and colored noise. Firstly, we obtain a significant criterion R0S which relies on environmental noises. By means of Lyapunov function approach, we show that there is a stationary distribution if R0S>1. Its condition implies that when white noise is small, in the stochastic model, there exists a stochastic positive equilibrium state without changing the basic properties of its corresponding deterministic model. Secondly, we derive sufficient criteria for extinction of the disease. Finally, we propose a definition of the solution to an impulsive stochastic functional differential equation with Markovian switching (ISFDM).

The relationship between Information and Communication Technology (ICT) and academic performance is a controversial issue that has attracted increasing attention from administrators, policymakers, and researchers. The relationship between perceived ICT competence and the academic performance of rural students deserves particular attention. Although a small but growing body of research has examined the relationship between perceived ICT competence and student academic performance, few studies have viewed perceived ICT competence as a multilevel construct. This study aimed to fill this gap by examining the relationship between multilevel perceived ICT competence (i.e., student- and school-level perceived ICT competence) and student academic performance using a sample of 5530 students from 156 schools in rural China. Two-level hierarchical linear modeling results indicated that student- and school-level perceived ICT competence could predict academic performance. Furthermore, school-level perceived ICT competence could moderate the relationship between student-level ICT competence and academic outcomes. Specifically, the role of student-level perceived ICT competence showed heterogeneity across schools. Academic performance was strongly correlated with student-level perceived ICT competence in schools with a low level of perceived ICT competence; in contrast, this outcome was not observed in schools with a high level of perceived ICT competence. The findings suggest that administrators and policymakers in China should pay special attention to rural schools where perceived ICT competence is low and consider providing services for students in these schools to promote educational equity.

Objective: To compare the ability of biofilm formation in 55 strains of Ureaplasma urealyticum (Uu) and their correlation with Uu resistance to macrolides. Methods: After in vitro biofilm cultures, optical density (OD) values of extracellular matrix of biofilm of Uu 55 strains were measured semi-quantitatively. The drug sensitivity tests (erythromycin, azithromycin, josamycin and clindamycin) were performed before and after biofilm formation. Paired t-test was used to determine the significances between the minimum inhibitory concentration (MIC) for Uu and the minimum biofilm inhibitory concentration (MBIC) for Uu biofilm. The relationship between OD value and log2 (MBIC/MIC) value was analyzed with simple linear regression. Results: For 55 Uu strains, MBICs were higher than MIC for all four antibiotics (all P

This paper studies a stochastic delay logistic model with Lévy jumps and impulsive perturbations. We show that the model has a unique global positive solution. Sufficient conditions for extinction, non-persistence in the mean, weak persistence, stochastic permanence and global asymptotic stability are established. The threshold between weak persistence and extinction is obtained. The results demonstrate that impulsive perturbations which may represent human factor play an important role in protecting the population even if it suffers sudden environmental shocks that can be discribed by Lévy jumps.

Neuroinflammation contributes to delayed (secondary) neurodegeneration following traumatic brain injury (TBI). Tumor necrosis factor receptor-associated factor 6 (TRAF6) signaling may promote post-TBI neuroinflammation, thereby exacerbating secondary injury. This study investigated the pathogenic functions of TRAF6 signaling following TBI in vivo and in vitro. A rat TBI model was established by air pressure contusion while lipopolysaccharide (LPS) exposure was used to induce inflammatory-like responses in cultured astrocytes. Model rats were examined for cell-specific expression of TRAF6, NF-κB, phosphorylated (p)-NF-κB, MAPKs (ERK, JNK, and p38), p-MAPKs, chemokines (CCL2 and CXCL1), and chemokine receptors (CCR2 and CXCR2) by immunofluorescence, RT-qPCR, western blotting, and ELISA, for apoptosis by TUNEL staining, and spatial cognition by Morris water maze testing. These measurements were compared between TBI model rats receiving intracerebral injections of TRAF6-targeted RNAi vector (AAV9-TRAF6-RNAi), empty vector, MAPK/NF-κB inhibitors, or vehicle. Primary astrocytes were stimulated with LPS following TRAF6 siRNA or control transfection, and NF-κB, MAPKs, chemokine, and chemokine receptor expression levels evaluated by western blotting and ELISA. TRAF6 was expressed mainly in astrocytes and neurons of injured cortex, peaking 3 days post-TBI. Knockdown by AAV9-TRAF6-RNAi improved spatial learning and memory, decreased TUNEL-positive cell number in injured cortex, and downregulated expression levels of p-NF-κB, p-ERK, p-JNK, p-p38, CCL2, CCR2, CXCL1, and CXCR2 post-TBI. Inhibitors of NF-κB, ERK, JNK, and p38 significantly suppressed CCL2, CCR2, CXCL1, and CXCR2 expression following TBI. Furthermore, TRAF6-siRNA inhibited LPS-induced NF-κB, ERK, JNK, p38, CCL2, and CXCL1 upregulation in cultured astrocytes. Targeting TRAF6-MAPKs/NF-κB-chemokine signaling pathways may provide a novel therapeutic approach for reducing post-TBI neuroinflammation and concomitant secondary injury.

Circular RNAs (circRNAs) are novel single-stranded noncoding RNAs that can decoy other RNAs to inhibit their functions. Kaposi's sarcoma (KS), caused by oncogenic Kaposi's sarcoma-associated herpesvirus (KSHV), is a highly angiogenic and invasive vascular tumor of endothelial origin commonly found in AIDS patients. We have recently shown that KSHV-encoded viral interferon regulatory factor 1 (vIRF1) induces cell invasion, angiogenesis and cellular transformation; however, the role of circRNAs is largely unknown in the context of KSHV vIRF1. Herein, transcriptome analysis identified 22 differentially expressed cellular circRNAs regulated by vIRF1 in an endothelial cell line. Among them, circARFGEF1 was the highest upregulated circRNA. Mechanistically, vIRF1 induced circARFGEF1 transcription by binding to transcription factor lymphoid enhancer binding factor 1 (Lef1). Importantly, upregulation of circARFGEF1 was required for vIRF1-induced cell motility, proliferation and in vivo angiogenesis. circARFGEF1 functioned as a competing endogenous RNAs (ceRNAs) by binding to and inducing degradation of miR-125a-3p. Mass spectrometry analysis demonstrated that glutaredoxin 3 (GLRX3) was a direct target of miR-125a-3p. Knockdown of GLRX3 impaired cell motility, proliferation and angiogenesis induced by vIRF1. Taken together, vIRF1 transcriptionally activates circARFGEF1, potentially by binding to Lef1, to promote cell oncogenic phenotypes via inhibiting miR-125a-3p and inducing GLRX3. These findings define a novel mechanism responsible for vIRF1-induced oncogenesis and establish the scientific basis for targeting these molecules for treating KSHV-associated cancers.

[This corrects the article DOI: 10.1371/journal.ppat.1007578.].

Kaposi's sarcoma (KS), caused by Kaposi's sarcoma-associated herpesvirus (KSHV), is a highly angioproliferative disseminated tumor of endothelial cells commonly found in AIDS patients. We have recently shown that KSHV-encoded viral interferon regulatory factor 1 (vIRF1) mediates KSHV-induced cell motility (PLoS Pathog. 2019 Jan 30;15(1):e1007578). However, the role of vIRF1 in KSHV-induced cellular transformation and angiogenesis remains unknown. Here, we show that vIRF1 promotes angiogenesis by upregulating sperm associated antigen 9 (SPAG9) using two in vivo angiogenesis models including the chick chorioallantoic membrane assay (CAM) and the matrigel plug angiogenesis assay in mice. Mechanistically, vIRF1 interacts with transcription factor Lef1 to promote SPAG9 transcription. vIRF1-induced SPAG9 promotes the interaction of mitogen-activated protein kinase kinase 4 (MKK4) with JNK1/2 to increase their phosphorylation, resulting in enhanced VEGFA expression, angiogenesis, cell proliferation and migration. Finally, genetic deletion of ORF-K9 from KSHV genome abolishes KSHV-induced cellular transformation and impairs angiogenesis. Our results reveal that vIRF1 transcriptionally activates SPAG9 expression to promote angiogenesis and tumorigenesis via activating JNK/VEGFA signaling. These novel findings define the mechanism of KSHV induction of the SPAG9/JNK/VEGFA pathway and establish the scientific basis for targeting this pathway for treating KSHV-associated cancers.

The power coordination control of a photovoltaic/battery microgrid is performed with a novel bio-computing model within the framework of membrane computing. First, a neural-like P system with state values (SVNPS) is proposed for describing complex logical relationships between different modes of Photovoltaic (PV) units and energy storage units. After comparing the objects in the neurons with the thresholds, state values will be obtained to determine the configuration of the SVNPS. Considering the characteristics of PV/battery microgrids, an operation control strategy based on bus voltages of the point of common coupling and charging/discharging statuses of batteries is proposed. At first, the SVNPS is used to construct the complicated unit working modes; each unit of the microgrid can adjust the operation modes automatically. After that, the output power of each unit is reasonably coordinated to ensure the operation stability of the microgrid. Finally, a PV/battery microgrid, including two PV units, one storage unit, and some loads are taken into consideration, and experimental results show the feasibility and effectiveness of the proposed control strategy and the SVNPS-based power coordination control models.

ABSTRACT The abnormal proliferation of cancer cells is driven by deregulated oncogenes or tumor suppressors, among which the cancer-vulnerable genes are attractive therapeutic targets. Targeting mislocalization of oncogenes and tumor suppressors resulting from aberrant nuclear export is effective for inhibiting growth transformation of cancer cells. We performed a clustered regularly interspaced short palindromic repeat (CRISPR)-associated (Cas) screening in a unique model of matched primary and oncogenic Kaposi’s sarcoma-associated herpesvirus (KSHV)-transformed cells and identified genes that were growth promoting and growth suppressive for both types of cells, among which exportin XPO1 was demonstrated to be critical for the survival of transformed cells. Using XPO1 inhibitor KPT-8602 and by small interfering RNA (siRNA) knockdown, we confirmed the essential role of XPO1 in cell proliferation and growth transformation of KSHV-transformed cells and in cell lines of other cancers, including gastric cancer and liver cancer. XPO1 inhibition induced cell cycle arrest through p53 activation, but the mechanisms of p53 activation differed among the different types of cancer cells. p53 activation depended on the formation of promyelocytic leukemia (PML) nuclear bodies in gastric cancer and liver cancer cells. Mechanistically, XPO1 inhibition induced relocalization of autophagy adaptor protein p62 (SQSTM1), recruiting p53 for activation in PML nuclear bodies. Taken the data together, we have identified novel growth-promoting and growth-suppressive genes of primary and cancer cells and have demonstrated that XPO1 is a vulnerable target of cancer cells. XPO1 inhibition induces cell arrest through a novel PML- and p62-dependent mechanism of p53 activation in some types of cancer cells. IMPORTANCE Using a model of oncogenic virus KSHV-driven cellular transformation of primary cells, we have performed a genome-wide CRISPR-Cas9 screening to identify vulnerable genes of cancer cells. This screening is unique in that this virus-induced oncogenesis model does not depend on any cellular genetic alterations and has matched primary and KSHV-transformed cells, which are not available for similar screenings in other types of cancer. We have identified genes that are both growth promoting and growth suppressive in primary and transformed cells, some of which could represent novel proto-oncogenes and tumor suppressors. In particular, we have demonstrated that the exportin XPO1 is a critical factor for the survival of transformed cells. Using a XPO1 inhibitor (KPT-8602) and siRNA-mediated knockdown, we have confirmed the essential role of XPO1 in cell proliferation and in growth transformation of KSHV-transformed cells, as well as of gastric and liver cancer cells. XPO1 inhibition induces cell cycle arrest by activating p53, but the mechanisms of p53 activation differed among different types of cancer cells. p53 activation is dependent on the formation of PML nuclear bodies in gastric and liver cancer cells. Mechanistically, XPO1 inhibition induces relocalization of autophagy adaptor protein p62 (SQSTM1), recruiting p53 for activation in PML nuclear bodies. These results illustrate that XPO1 is a vulnerable target of cancer cells and reveal a novel mechanism for blocking cancer cell proliferation by XPO1 inhibition as well as a novel PML- and p62-mediated mechanism of p53 activation in some types of cancer cells.

Kaposi's sarcoma (KS), a highly disseminated tumor of hyperproliferative spindle endothelial cells, is the most common AIDS-associated malignancy caused by infection of Kaposi's sarcoma-associated herpesvirus (KSHV). KSHV-encoded viral interferon regulatory factor 1 (vIRF1) is a viral oncogene but its role in KSHV-induced tumor invasiveness and motility remains unknown. Here, we report that vIRF1 promotes endothelial cell migration, invasion and proliferation by down-regulating miR-218-5p to relieve its suppression of downstream targets high mobility group box 2 (HMGB2) and cytidine/uridine monophosphate kinase 1 (CMPK1). Mechanistically, vIRF1 inhibits p53 function to increase the expression of DNA methyltransferase 1 (DNMT1) and DNA methylation of the promoter of pre-miR-218-1, a precursor of miR-218-5p, and increases the expression of a long non-coding RNA OIP5 antisense RNA 1 (lnc-OIP5-AS1), which acts as a competing endogenous RNA (ceRNA) of miR-218-5p to inhibit its function and reduce its stability. Moreover, lnc-OIP5-AS1 increases DNA methylation of the pre-miR-218-1 promoter. Finally, deletion of vIRF1 from the KSHV genome reduces the level of lnc-OIP5-AS1, increases the level of miR-218-5p, and inhibits KSHV-induced invasion. Together, these results define a novel complex lnc-OIP5-AS1/miR-218-5p network hijacked by vIRF1 to promote invasiveness and motility of KSHV-induced tumors.

Abstract: Immunosuppressive drugs and biological agents may represent a potential risk of lymphoma development in patients with rheumatoid arthritis. But most cases are diffuse, large B-cell lymphomas. Primary cutaneous CD4+ small/medium-sized pleomorphic T-cell lymphoma, a provisional entity in the 2005 WHO-EORTC classification of cutaneous lymphomas, is only described in a limited number of reports. To our knowledge, our case is a rare instance of primary cutaneous CD4+ small/medium-sized pleomorphic T-cell lymphoma, after associated treatment with methotrexate and etanercept, in a patient with moderate rheumatoid arthritis who had undergone an orchidectomy incorrectly.

Background: Cathepsin L (CatL) is a cysteine protease with strong matrix degradation activity that contributes to photoaging. Mannose phosphate-independent sorting pathways mediate ultraviolet A (UVA)-induced alternate trafficking of CatL. Little is known about signaling pathways involved in the regulation of UVA-induced CatL expression and activity. This study aims to investigate whether a single UVA irradiation affects CatL expression and activity and whether mitogen-activated protein kinase (MAPK)/activator protein-1 (AP-1) pathway is involved in the regulation of UVA-induced CatL expression and activity in human dermal fibroblasts (HDFs). Methods: Primary HDFs were exposed to UVA. Cell proliferation was determined by a cell counting kit. UVA-induced CatL production and activity were studied with quantitative real-time reverse transcription polymerase chain reaction (RT-PCR), Western blotting, and fluorimetric assay in cell lysates collected on three consecutive days after irradiation. Time courses of UVA-activated JNK and p38MAPK signaling were examined by Western blotting. Effects of MAPK inhibitors and knockdown of Jun and Fos on UVA-induced CatL expression and activity were investigated by RT-PCR, Western blotting, and fluorimetric assay. Data were analyzed by one-way analysis of variance. Results: UVA significantly increased CatL gene expression, protein abundance, and enzymatic activity for three consecutive days after irradiation (F = 83.11, 56.14, and 71.19, respectively; all P < 0.05). Further investigation demonstrated phosphorylation of JNK and p38MAPK activated by UVA. Importantly, inactivation of JNK pathway significantly decreased UVA-induced CatL expression and activity, which were not affected by p38MAPK inhibition. Moreover, knockdown of Jun and Fos significantly attenuated basal and UVA-induced CatL expression and activity. Conclusions: UVA enhances CatL production and activity in HDFs, probably by activating JNK and downstreaming AP-1. These findings provide a new possible molecular approach for antiphotoaging therapy.

The prognosis of advanced non-small cell lung cancer (NSCLC) patients is poor. One of the reasons for this hampered progress has been a lack of in vitro models that would faithfully recapitulate the heterogeneity of tumors and response to treatment. In this study, surgically resected tumors were obtained from patients with stage I/II NSCLC during curative-intent surgery. Using a 3D patient-derived tumor spheroids culture system, our results demonstrate successful long-term expansion of primary NSCLC cells in vitro (> 120 days). Patient-derived tumor spheroid (PDS) cultures could be established with a success rate of 100% (3 out of 3 samples). Consistent with their growth in culture and their cancer type, many cells within the tumor spheroids were stained positive for Ki67 and thyroid transcription factor-1. The result of this study supports the establishment of an expandable 3D in vitro NSCLC model for drug screening, and enables the potential long term studies such as the establishment of drug resistant models.

This article investigates a stochastic logistic model with Levy noise and impulsive perturbation. In the model, the impulsive perturbation and Levy noise are taken into account simultaneously. This model is new and more feasible and more accordance with the actual. The definition of solution to a stochastic differential equation with Levy noise and impulsive perturbation is established. Based on this definition, we show that our model has a unique global positive solution and obtains its explicit expression. Sufficient conditions for extinction are established as well as nonpersistence in the mean, weak persistence and stochastic permanence. The threshold between weak persistence and extinction is obtained.

AbstractEccrine poroma is a benign adnexal tumour of the uppermost portion of the intraepidermal eccrine sweat gland duct and acrosyringium. Eccrine porocarcinoma is the malignant phenotype arising from the intraepidermal portion of the eccrine sweat gland duct epithelium or from pre-existing eccrine poroma. Both commonly occur in the palms or sides of the feet; these areas have a high concentration of eccrine sweat glands. We describe two respective cases of benign and malignant eccrine poroma on the scrotum, which entailed good excisional results.

Abstract: Primary localized cutaneous amyloidosis is a skin-limited amyloidosis that does not involve internal organs. It is clinically subclassified into 3 general categories and some rare variants. However, there is considerable overlap within the classification. Though there are a variety of therapeutic measures, the treatment is often unsatisfactory, particularly when the disease is severe and extensive. We describe a rare case of primary localized cutaneous amyloidosis with lichen and poikiloderma-like lesions that showed an excellent response to systemic acitretin.

ABSTRACT While glutamine is a nonessential amino acid that can be synthesized from glucose, some cancer cells primarily depend on glutamine for their growth, proliferation, and survival. Numerous types of cancer also depend on asparagine for cell proliferation. The underlying mechanisms of the glutamine and asparagine requirement in cancer cells in different contexts remain unclear. In this study, we show that the oncogenic virus Kaposi’s sarcoma-associated herpesvirus (KSHV) accelerates the glutamine metabolism of glucose-independent proliferation of cancer cells by upregulating the expression of numerous critical enzymes, including glutaminase 2 (GLS2), glutamate dehydrogenase 1 (GLUD1), and glutamic-oxaloacetic transaminase 2 (GOT2), to support cell proliferation. Surprisingly, cell crisis is rescued only completely by supplementation with asparagine but minimally by supplementation with α-ketoglutarate, aspartate, or glutamate upon glutamine deprivation, implying an essential role of γ-nitrogen in glutamine and asparagine for cell proliferation. Specifically, glutamine and asparagine provide the critical γ-nitrogen for purine and pyrimidine biosynthesis, as knockdown of four rate-limiting enzymes in the pathways, including carbamoylphosphate synthetase 2 (CAD), phosphoribosyl pyrophosphate amidotransferase (PPAT), and phosphoribosyl pyrophosphate synthetases 1 and 2 (PRPS1 and PRPS2, respectively), suppresses cell proliferation. These findings indicate that glutamine and asparagine are shunted to the biosynthesis of nucleotides and nonessential amino acids from the tricarboxylic acid (TCA) cycle to support the anabolic proliferation of KSHV-transformed cells. Our results illustrate a novel mechanism by which an oncogenic virus hijacks a metabolic pathway for cell proliferation and imply potential therapeutic applications in specific types of cancer that depend on this pathway. IMPORTANCE We have previously found that Kaposi’s sarcoma-associated herpesvirus (KSHV) can efficiently infect and transform primary mesenchymal stem cells; however, the metabolic pathways supporting the anabolic proliferation of KSHV-transformed cells remain unknown. Glutamine and asparagine are essential for supporting the growth, proliferation, and survival of some cancer cells. In this study, we have found that KSHV accelerates glutamine metabolism by upregulating numerous critical metabolic enzymes. Unlike most cancer cells that primarily utilize glutamine and asparagine to replenish the TCA cycle, KSHV-transformed cells depend on glutamine and asparagine for providing γ-nitrogen for purine and pyrimidine biosynthesis. We identified four rate-limiting enzymes in this pathway that are essential for the proliferation of KSHV-transformed cells. Our results demonstrate a novel mechanism by which an oncogenic virus hijacks a metabolic pathway for cell proliferation and imply potential therapeutic applications in specific types of cancer that depend on this pathway.

AbstractPhacomatosis pigmentovascularis is a rare, congenital condition characterized by a combination of cutaneous melanocytic lesions and vascular malformation. We discuss an entirely unique case of Phacomatosis pigmentovascularis with nevus of Ota, extensive Mongolian spot, nevus flammeus, nevus anemicus and cutis marmorata telangiectatica congenita, which may represent a heretofore undescribed variant of phacomatosis pigmentovascularis.

This article, studies a stochastic logistic model with infinite delay. Using a phase space, we establish sufficient conditions for the extinction, nonpersistence in the mean, weak persistence, and stochastic permanence. A threshold between weak persistence and extinction is obtained. Our results state that different types of environmental noises have different effects on the persistence and extinction, and that the delay has no impact on the persistence and extinction for the stochastic model in the autonomous case. Numerical simulations illustrate the theoretical results.

Mantel cell lymphoma is one of the small B-cell non-Hodgkin's lymphomas and usually involves lymph nodes, bone marrow, spleen, liver, gastrointestinal tract, and Waldeyer's ring, but rarely skin and orbit. A 53-year-old man presented skin nodules and plaques on the head, trunk, and lower extremities for half a month, and the left periorbital region swelled 4 days ago. Serum calcium and lactate dehydrogenase were increased to 3.12 mmol/L (normal 2.03–2.65 mmol/L) and 853 U/L (normal 71–231 U/L), respectively. Histopathologic examination of the skin nodule revealed tumor cells infiltrated nodular distribution in the dermis and subcutaneous tissue. Immunophenotyping of the abnormal lymphocytes indicated positive reactions for L26, CD79a, Bcl-2, Cyclin D1, and Ki-67 (>80%), but negative for CD5, CD21, CD23, CD38, CD3, CD10, UCHL-1, TdT, MPO, CD30, ALK, CD117, and CD34. Fluorescence in situ hybridization analysis with the CCND1/IGH probe revealed a fusion signal on the abnormal lymphocytes. The final diagnosis was a rare case of blastoid mantle cell lymphoma involving skin and orbit with hypercalcemia. Following the R-Hyper-CVAD treatment plan, the patient achieved a quick and excellent recovery on the 6th day. Unfortunately, the patient eventually died of pneumonia one month later.

Aerobic glycolysis is essential for supporting the fast growth of a variety of cancers. However, its role in the survival of cancer cells under stress conditions is unclear. We have previously reported an efficient model of gammaherpesvirus Kaposi's sarcoma-associated herpesvirus (KSHV)-induced cellular transformation of rat primary mesenchymal stem cells. KSHV-transformed cells efficiently induce tumors in nude mice with pathological features reminiscent of Kaposi's sarcoma tumors. Here, we report that KSHV promotes cell survival and cellular transformation by suppressing aerobic glycolysis and oxidative phosphorylation under nutrient stress. Specifically, KSHV microRNAs and vFLIP suppress glycolysis by activating the NF-κB pathway to downregulate glucose transporters GLUT1 and GLUT3. While overexpression of the transporters rescues the glycolytic activity, it induces apoptosis and reduces colony formation efficiency in softagar under glucose deprivation. Mechanistically, GLUT1 and GLUT3 inhibit constitutive activation of the AKT and NF-κB pro-survival pathways. Strikingly, GLUT1 and GLUT3 are significantly downregulated in KSHV-infected cells in human KS tumors. Furthermore, we have detected reduced levels of aerobic glycolysis in several KSHV-infected primary effusion lymphoma cell lines compared to a Burkitt's lymphoma cell line BJAB, and KSHV infection of BJAB cells reduced aerobic glycolysis. These results reveal a novel mechanism by which an oncogenic virus regulates a key metabolic pathway to adapt to stress in tumor microenvironment, and illustrate the importance of fine-tuning the metabolic pathways for sustaining the proliferation and survival of cancer cells, particularly under stress conditions.

Kaposi's sarcoma (KS)-associated herpesvirus (KSHV) is a gammaherpesvirus etiologically associated with KS, a highly disseminated angiogenic tumor of hyperproliferative spindle endothelial cells. KSHV encodes 25 mature microRNAs but their roles in KSHV-induced tumor dissemination and angiogenesis remain unknown. Here, we investigated KSHV-encoded miR-K12-6-3p (miR-K6-3p) promotion of endothelial cell migration and angiogenesis, which are the underlying mechanisms of tumor dissemination and angiogenesis. We found that ectopic expression of miR-K6-3p promoted endothelial cell migration and angiogenesis. Mass spectrometry, bioinformatics and luciferase reporter analyses revealed that miR-K6-3p directly targeted sequence in the 3' untranslated region (UTR) of SH3 domain binding glutamate-rich protein (SH3BGR). Overexpression of SH3BGR reversed miR-K6-3p induction of cell migration and angiogenesis. Mechanistically, miR-K6-3p downregulated SH3BGR, hence relieved STAT3 from SH3BGR direct binding and inhibition, which was required for miR-K6-3p maximum activation of STAT3 and induction of cell migration and angiogenesis. Finally, deletion of miR-K6 from the KSHV genome abrogated its effect on the SH3BGR/STAT3 pathway, and KSHV-induced migration and angiogenesis. Our results illustrated that, by inhibiting SH3BGR, miR-K6-3p enhances cell migration and angiogenesis by activating the STAT3 pathway, and thus contributes to the dissemination and angiogenesis of KSHV-induced malignancies.

ABSTRACT Kaposi’s sarcoma (KS), a highly angiogenic and invasive tumor often involving different organ sites, including the oral cavity, is caused by infection with Kaposi’s sarcoma-associated herpesvirus (KSHV). Diverse cell markers have been identified on KS tumor cells, but their origin remains an enigma. We previously showed that KSHV could efficiently infect, transform, and reprogram rat primary mesenchymal stem cells (MSCs) into KS-like tumor cells. In this study, we showed that human primary MSCs derived from diverse organs, including bone marrow (MSCbm), adipose tissue (MSCa), dental pulp, gingiva tissue (GMSC), and exfoliated deciduous teeth, were permissive to KSHV infection. We successfully established long-term cultures of KSHV-infected MSCa, MSCbm, and GMSC (LTC-KMSCs). While LTC-KMSCs had lower proliferation rates than the uninfected cells, they expressed mixtures of KS markers and displayed differential angiogenic, invasive, and transforming phenotypes. Genetic analysis identified KSHV-derived microRNAs that mediated KSHV-induced angiogenic activity by activating the AKT pathway. These results indicated that human MSCs could be the KSHV target cells in vivo and established valid models for delineating the mechanism of KSHV infection, replication, and malignant transformation in biologically relevant cell types. IMPORTANCE Kaposi’s sarcoma is the most common cancer in AIDS patients. While KSHV infection is required for the development of Kaposi’s sarcoma, the origin of KSHV target cells remains unclear. We show that KSHV can efficiently infect human primary mesenchymal stem cells of diverse origins and reprogram them to acquire various degrees of Kaposi’s sarcoma-like cell makers and angiogenic, invasive, and transforming phenotypes. These results indicate that human mesenchymal stem cells might be the KSHV target cells and establish models for delineating the mechanism of KSHV-induced malignant transformation.

Kaposi sarcoma-associated herpesvirus (KSHV) is necessary but not sufficient to cause Kaposi sarcoma (KS). Coinfection with human immunodeficiency virus type 1 (HIV-1), in the absence of antiretroviral suppressive therapy, drastically increases the risk of KS. Previously, we identified that HIV-1 transactivative transcription protein (Tat) was an important cofactor that activated lytic cycle replication of KSHV. Here, we further investigated the potential of Tat to influence tumorigenesis induced by KSHV Kaposin A, a product of KSHV that was encoded by the open reading frame K12 (a KSHV-transforming gene). By using colony formation in soft agar, 3H-TdR incorporation, cell cycle, and microarray gene expression analyses, we demonstrated that Tat enhanced proliferation as well as mitogen-activated protein kinase, signal transducer and activator of transcription 3, and phosphatidylinositol 3-kinase/protein kinase B signaling induced by Kaposin A in NIH3T3 cells. Animal experiments further demonstrated that Tat accelerated tumorigenesis by Kaposin A in athymic nu/nu mice. Cells obtained from primary tumors of nude mice succeeded inducing tumors in immunocompetent mice. These data suggest that Tat can accelerate tumorigenesis induced by Kaposin A. Our data present the first line of evidence that Tat may participate in KS pathogenesis by collaborating with Kaposin A in acquired immunodeficiency syndrome (AIDS)-related KS (AIDS-KS) patients. Our data also suggest that the model for Kaposin and Tat-mediated oncogenesis will contribute to our understanding of the pathogenesis of AIDS-KS at the molecular level and may even be important in exploring a novel therapeutic method for AIDS-KS.

Kaposi's sarcoma (KS) is a highly disseminated angiogenic tumor of endothelial cells linked to infection by Kaposi's sarcoma-associated herpesvirus (KSHV). KSHV encodes more than two dozens of miRNAs but their roles in KSHV-induced tumor dissemination and metastasis remain unknown. Here, we found that ectopic expression of miR-K12-3 (miR-K3) promoted endothelial cell migration and invasion. Bioinformatics and luciferase reporter analyses showed that miR-K3 directly targeted G protein-coupled receptor (GPCR) kinase 2 (GRK2, official gene symbol ADRBK1). Importantly, overexpression of GRK2 reversed miR-K3 induction of cell migration and invasion. Furthermore, the chemokine receptor CXCR2, which was negatively regulated by GRK2, was upregulated in miR-K3-transduced endothelial cells. Knock down of CXCR2 abolished miR-K3-induced cell migration and invasion. Moreover, miR-K3 downregulation of GRK2 relieved its direct inhibitory effect on AKT. Both CXCR2 induction and the release of AKT from GRK2 were required for miR-K3 maximum activation of AKT and induction of cell migration and invasion. Finally, deletion of miR-K3 from the KSHV genome abrogated its effect on the GRK2/CXCR2/AKT pathway and KSHV-induced migration and invasion. Our data provide the first-line evidence that, by repressing GRK2, miR-K3 facilitates cell migration and invasion via activation of CXCR2/AKT signaling, which likely contribute to the dissemination of KSHV-induced tumors.