MicroRNA-1915-3p inhibits cell migration and invasion by targeting SET in non-small-cell lung cancer.

BACKGROUND: MicroRNAs (miRNAs) have been reported to play significant roles in non-small-cell lung cancer (NSCLC). However, the roles of microRNA (miR)-1915-3p in NSCLC remain unclear. In this study, we aimed to explore the biological functions of miR-1915-3p in NSCLC. METHODS: The expression of miR-1915-3p and SET nuclear proto-oncogene (SET) in NSCLC tissues were examined by quantitative real-time PCR (qRT-PCR). Migratory and invasive abilities of lung cancer were tested by wound healing and transwell invasion assay. The direct target genes of miR-1915-3p were measured by dual-luciferase reporter assay and western blot. Finally, the regulation between METTL3/YTHDF2/KLF4 axis and miR-1915-3p were evaluated by qRT-PCR, promoter reporter assay and chromatin immunoprecipitation (CHIP). RESULTS: miR-1915-3p was downregulated in NSCLC tissues and cell lines, and inversely associated with clinical TNM stage and overall survival. Functional assays showed that miR-1915-3p significantly suppressed migration, invasion and epithelial-mesenchymal transition (EMT) in NSCLC cells. Furthermore, miR-1915-3p directly bound to the 3'untranslated region (3'UTR) of SET and modulated the expression of SET. SET inhibition could recapitulate the inhibitory effects on cell migration, invasion and EMT of miR-1915-3p, and restoration of SET expression could abrogate these effects induced by miR-1915-3p through JNK/Jun and NF-κB signaling pathways. What's more, miR-1915-3p expression was regulated by METTL3/YTHDF2 m6A axis through transcription factor KLF4. CONCLUSIONS: These findings demonstrate that miR-1915-3p function as a tumor suppressor by targeting SET and may have an anti-metastatic therapeutic potential for lung cancer treatment.

Regulation of MALAT1 expression by TDP43 controls the migration and invasion of non-small cell lung cancer cells in vitro.

MALAT1 is a non-coding RNA overexpressed in non-small cell lung cancer (NSCLC). TDP-43 is a ubiquitously expressed, MALAT1-binding protein implicated in cancer development. We hypothesized that MALAT1 expression level is regulated in lung cancer by TDP-43. We analyzed their functions in cultured NSCLC cells. Downregulation of MALAT1 or TDP-43 expression by siRNA not only markedly suppressed NSCLC cell growth, as measured by the MTT assay in vitro cultured NSCLC cells (P < 0.05), but also noticeably impaired the migration and invasion of NSCLC cells, as analyzed by the migration and invasion assay. We also confirm that TDP-43 directly bound to MALAT1 RNA by a RNA immunoprecipitation (RIP) assay and by luciferase reporter activity assay. In a RT-PCR assay, silencing TDP-43 expression effectively decreased MALAT1 RNA transcript level. In contrast, TDP-43 overexpression markedly increased MALAT1 transcript level. In summary, these findings demonstrated that MALAT1 expression by regulation of TDP-43 controls cellular growth, migration, and invasion of NSCLCs.

Analysis and Verification of Heat Dissipation Structures Embedded in Substrates in Power Chips Based on Square Frustums Thermal through Silicon Vias.

A novel heat dissipation structure composed of square frustums thermal through silicon via array and embedded in P-type (100) silicon substrate is proposed to improve the heat dissipation capacity of power chips while reducing process difficulty. Based on theoretical analysis, the heat transfer model and thermo-electric coupling reliability model of a power chip with the proposed heat dissipation structure are established. A comparative study of simulation indicates that the proposed heat dissipation structure, which can avoid problems such as softness, poor rigidity, fragility and easy fracture caused by thinning chips has better heat dissipation capability than thinning the substrate of power chips.

Exploring the oncogenic potential of Aiolos in lung cancer through OTUB1-mediated ubiquitination.

Aiolos (IKZF3), a zinc finger transcription factor, has been identified in various solid tumors. While most research on Aiolos focuses on its role in the hematopoietic system, its expression patterns, mechanisms of action, and biological impacts in lung cancer remain relatively unexplored. This study investigates Aiolos' role in the proliferation, migration, and invasion of lung cancer cells. Our findings indicate that Aiolos overexpression enhances these cellular processes, suggesting its potential contribution to the advancement of the disease. However, the precise mechanisms underlying these effects require further investigation. Additionally, we identified OTUB1 as a potential Aiolos-interacting protein. OTUB1, a deubiquitinating enzyme, removes ubiquitin chains from target proteins, thereby affecting their stability, function, or localization. Our results suggest that OTUB1 specially bound to Aiolos and reduces its ubiquitination, which may influence Aiolos-related biological functions, including cell migration and invasion. This study highlights the pivotal roles of Aiolos and OTUB1 in lung cancer progression, potentially offering new therapeutic targets.

Integrative analysis of single-cell and bulk RNA-sequencing data revealed T cell marker genes based molecular sub-types and a prognostic signature in lung adenocarcinoma.

Immunotherapy has emerged as a promising modality for addressing advanced or conventionally drug-resistant malignancies. When it comes to lung adenocarcinoma (LUAD), T cells have demonstrated significant influence on both antitumor activity and the tumor microenvironment. However, their specific contributions remain largely unexplored. This investigation aimed to delineate molecular subtypes and prognostic indicators founded on T cell marker genes, thereby shedding light on the significance of T cells in LUAD prognosis and precision treatment. The cellular phenotypes were identified by scrutinizing the single-cell data obtained from the GEO repository. Subsequently, T cell marker genes derived from single-cell sequencing analyses were integrated with differentially expressed genes from the TCGA repository to pinpoint T cell-associated genes. Utilizing Cox analysis, molecular subtypes and prognostic signatures were established and subsequently verified using the GEO dataset. The ensuing molecular and immunological distinctions, along with therapy sensitivity between the two sub-cohorts, were examined via the ESTIMATE, CIBERSORT, and ssGSEA methodologies. Compartmentalization, somatic mutation, nomogram development, chemotherapy sensitivity prediction, and potential drug prediction analyses were also conducted according to the risk signature. Additionally, real-time qPCR and the HPA database corroborated the mRNA and protein expression patterns of signature genes in LUAD tissues. In summary, this research yielded an innovative T cell marker gene-based signature with remarkable potential to prognosis and anticipate immunotherapeutic outcomes in LUAD patients.

Down-regulation of microRNA-23a promotes pancreatic ductal adenocarcinoma initiation and progression by up-regulation of FOXM1 expression.

Transcriptional factor Forkhead box M1 (FOXM1) plays an important role in pancreatic ductal adenocarcinoma (PDAC) development and progression. The molecular mechanisms underlying its dysregulation remain unclear. We identified and functionally validated the microRNAs (miRNAs) that critically regulate FOXM1 expression in PDAC. The expression levels of miRNA-23a (miR-23a-3p and -5p) were altered in PDAC cell lines and their effects on FOXM1 signaling and cell proliferation and migration and tumorigenesis were examined in vitro and in vivo using mouse PDAC models. Compared with non-tumor pancreatic tissues, PDAC tissues and cell lines exhibited significantly reduced levels of miR-23a expression. Reduced miR-23a expression and concomitant increase in FOXM1 expression were also observed in acinar-to-ductal metaplasia and pancreatic intraepithelial neoplasia, the major premalignant lesions of PDAC. Transgenic expression of miR-23a reduced the expression of FOXM1 and suppressed cell proliferation and migration in PDAC cells, whereas the inhibitors of miR-23a did the opposite. Loss or reduced levels of miR-23a increased the levels of FOXM1 expression, while increased expression of FOXM1 down-regulated miR-23a expression, suggesting that miR-23a and FOXM1 were mutual negative regulators of their expression in PDAC cells. Therefore, the miR-23a/FOXM1 signaling axis is important in PDAC initiation and progression and could serve as an interventional or therapeutic target for patients with early or late stages of PDAC.

The inhibitory effects of Endostar combined with chemotherapy on human esophageal squamous cell carcinoma xenograft in mice.

The purpose of this study was to investigate the efficacy of Endostar combined with chemotherapy on human esophageal squamous cell carcinoma Eca-109 in mice. The tumor xenograft models were established and randomly assigned to 4 groups: control group, Endostar group (1.5 mg/kg day, once daily for 3 weeks), chemotherapy group (Paclitaxel 10 mg/kg day, Cisplatin 5 mg/kg day, for 1, 7, 14, 21 days), and chemotherapy + Endostar group (combination). The length and width of tumor were measured and the tumor volumes (cm(3)) were calculated every other day. Three weeks later, the mice were executed, and the tumor tissues were collected to weigh and analyse the histopathology and proliferation for tumor xenograft. The results demonstrated that the tumor volumes and weight in chemotherapy + Endostar group were significantly lower than that in other three groups. Meanwhile, the cell proliferation of tumor xenograft in combined treatment group was significantly lower than that in other three groups. It was concluded that Endostar combined with chemotherapy could obviously enhance the inhibitory effect on esophageal squamous cell carcinoma Eca-109 in mice.

Identification of genes associated with tumor development in CaSki cells in the cosmic space.

It is important to understand the mechanisms of tumor development for curing cervical cancer. However, the molecular basis determining the different characteristics of tumor remains unclear. Space environment as a special study model can expand the study field of tumor development. To approach this, after human cervical carcinoma CaSki cells were flown on "Shen Zhou IV" space shuttle mission, the cell morphology and proliferation was investigated after flying to ground. We found that the growth of 48A9 CaSki cell (flight group) became slow compared with ground groups. Observation of cells by light microscopy revealed differences in cell morphology between ground controls and flight groups, and the flight group exhibited morphologic differences, characterized by rounder, smoother, decreased, smaller and low-adhension cells. Transmission electron microscope images showed the structure of the ultrastructural characteristics of 48A9 CaSki cells were clearly distinct from those of the ground CaSki cells in aspects of mitochondrion, cytoplasm, nucleus and ribosomes. MTT and soft agar assay showed that 48A9 CaSki cells grew slowly compared to ground control. Furthermore, suppression subtractive hybridization combining with reverse Northern blot was used to identify differently expression genes between flight and ground groups. These differentially expressed genes included cytoskeleton, cell differentiation, cell apoptosis, signal transduction, DNA repair, protein synthesis, substance metabolism, and antigen presentation. The identification of differently expressed genes which is likely to increase our understanding of the molecular processes underlying tumor development will provide new insight into tumor development mechanisms, and may facilitate the development of new anticancer strategies.

The Inhibitory Effect of Regulatory T Cells on the Intimal Hyperplasia of Tissue-Engineered Blood Vessels in Diabetic Pigs.

Severe inflammatory response and functional impairment of endothelial progenitor cells (EPCs) often lead to the implantation failure of EPC-captured tissue-engineered blood vessels (TEBVs) in diabetes. Regulatory T cells (Treg cells) are the most important inhibitory immune cells, but their effects in angiogenesis remain undefined, and the differences in the microenvironment may be an important reason. Here, we constructed a TEBV coated with an anti-CD34 antibody-functionalized heparin-collagen multilayer (anti-CD34 antibody-modified TEBV) using layer-by-layer self-assembly. Then, TEBVs were implanted into diabetic pigs. All TEBVs remained unobstructed 60 days after implantation, although varying degrees of intimal hyperplasia were detectable. Severe intimal hyperplasia was observed in the control group and peripheral injection of Treg cells group. Intravenous injection of Treg cells significantly inhibited intimal hyperplasia, inflammation, and cell apoptosis. Moreover, intravenous injection increased the proportion of circulating EPCs, while peripheral injection did not have these effects and reduced microvessel density around the TEBV. Interestingly, many Nestin+ cells could be detected in TEBVs, most of which were fusiform, showing the characteristics of smooth-muscle cells. Treg cell intravenous transplantation markedly reduced the number of Nestin+ cells in the TEBV. In conclusion, Treg cells inhibited the intimal hyperplasia of TEBVs in diabetic pigs by promoting EPC mobilization, anti-inflammatory action, and cellular protection.

Aptamer-siRNA chimera and gold nanoparticle modified collagen membrane for the treatment of malignant pleural effusion.

Malignant pleural effusion is one of the most common complications of advanced lung cancer and there is no effective clinical treatment at present. Here, we constructed an aptamer-siRNA chimeras/PEI/PEG/gold nanoparticle (AuNP)/collagen membrane that can progressively activate T cells by layer by layer assembly. Electron microscope showed this collagen membrane could be divided into 10 layers with a total thickness of 50-80µm, and AuNPs could be observed. Aptamer-siRNA chimeras could bind specifically to OX40+ cells and silencing programmed death receptor-1 (PD-1) gene. In vitro experiments demonstrated that chimeras/PEI/PEG/AuNPs gradually activated T cells to continuously kill lung adenocarcinoma cells in malignant pleural effusion. Animal experiments showed that chimeras/PEI/PEG/AuNP/collagen membrane effectively treated malignant pleural effusion. Compared with PD-1 inhibitor group, the number of cancer cells, ki-67 proliferation index and CD44 expression in the pleural effusion was significantly decreased and the lymphocyte/cancer cell ratio was significantly increased in the chimeras/AuNP-CM group. Flow cytometry showed that compared with PD-1 inhibitor group, T cell number in the chimeras/AuNP-CM group was significantly increased, while the proportion of PD-1+ T cells was markedly decreased. In conclusion, we constructed an chimeras/PEI/PEG/AuNP/collagen membrane, which was more effective in the treatment of malignant pleural effusion, and had less side effects than PD-1 inhibitors.

Photon-Energy-Dependent Reversible Charge Transfer Dynamics of Double Perovskite Nanocrystal-Polymer Nanocomposites.

Combining steady-state photoluminescence and transient absorption (TA) spectroscopy, we have investigated the photoinduced charge transfer dynamics between lead-free Mn-doped Cs2NaIn0.75Bi0.25Cl6 double perovskite (DP) nanocrystals (NCs) and conjugated poly[2-methoxy-5-(3',7'-dimethyloctyloxy)-1,4-phenylenevinylene] (MDMO-PPV). Upon ultraviolet-A excitation, the photoinduced absorption feature of DP NCs/MDMO-PPV nanocomposites disappeared, and the stimulated emission weakened in the TA spectrum. This was due to charge transfer from the MDMO-PPV polymers to DP NCs. Upon a higher photon-energy ultraviolet-C excitation, stimulated emission and photoinduced absorption features vanished, indicating there existed a reversible charge transfer from DP NCs to MDMO-PPV polymers. Reversible charge transfer of Mn-doped DP NCs/MDMO-PPV nanocomposites was tuned by varying the excitation photon-energy. The manipulation of reversible charge transfer dynamics in the perovskite-polymer nanocomposites opens a new avenue for optical and optoelectronic applications.

MiR-192/NKRF axis confers lung cancer cell chemoresistance to cisplatin via the NF-κB pathway.

BACKGROUND: Chemoresistance influences the therapeutic effect of cisplatin and remains a major obstacle to its clinical use. MicroRNAs are associated with drug resistance of various tumors. However, the association between microRNAs and cisplatin in lung cancer remains largely unclear. METHODS: MicroRNA expression profile was identified by microRNA microarray between the lung cancer cisplatin-sensitive cell line A549 (A549) and cisplatin-resistant cell line A549/DDP (A549/DDP) and confirmed by quantitative real-time-PCR (qRT-PCR). In vitro loss- and gain-of-function studies were performed to reveal the biological function of miR-192 and related mechanism of the microRNA-192/NKRF axis in lung cancer cell cisplatin resistance. RESULTS: Increased miR-192 expression was detected in A549/DDP cells compared to A549. High miR-192 expression significantly suppressed apoptosis, enhanced proliferation, and conferred resistance to cisplatin in lung cancer cells. NF-κB repressing factor (NKRF), which is involved in the regulation of the NF-κB signaling pathway, was identified as a direct target of miR-192. Overexpression of miR-192 significantly increased the nuclear protein amount and transcriptional activation of NF-κB and expression of cIAP1, cIAP2, Bcl-xl and XIAP, whereas decreased miR-192 expression did the opposite. Inhibition of the NF-κB signal pathway by curcumin reversed the effect of upregulation of miR-192 on proliferation, apoptosis and cisplatin-resistance in lung cancer cells. These results indicated that miR-192/ NKRF axis enhances the cisplatin resistance of lung cancer cells through activating the NF-κB pathway in vitro. CONCLUSIONS: MiR-192 plays a crucial role in cisplatin-resistance of lung cancer cells. Thus, MiR-192 may represent a therapeutic target for overcoming resistance to cisplatin-based chemotherapy in lung cancer.

miR-223 regulates migration and invasion by targeting Artemin in human esophageal carcinoma.

BACKGROUND: Artemin (ARTN) is a neurotrophic factor belonging to the glial cell-derived neurotrophic factor family of ligands. To develop potential therapy targeting ARTN, we studied the roles of miR-223 in the migration and invasion of human esophageal carcinoma. METHODS: ARTN expression levels were detected in esophageal carcinoma cell lines KYSE-150, KYSE-510, EC-9706, TE13, esophageal cancer tissues and paired non-cancerous tissues by Western blot. Artemin siRNA expression vectors were constructed to knockdown of artemin expression mitigated migration and invasiveness in KYSE150 cells. Monolayer wound healing assay and Transwell invasion assay were applied to observe cancer cell migration and invasion. The relative levels of expression were quantified by real-time quantitative PCR. RESULTS: ARTN expression levels were higher in esophageal carcinoma tissue than in the adjacent tissue and was differentially expressed in various esophageal carcinoma cell lines. ARTN mRNA contains a binding site for miR-223 in the 3'UTR. Co-transfection of a mir-223 expression vector with pMIR-ARTN led to the reduced activity of luciferase in a dual-luciferase reporter gene assay, suggesting that ARTN is a target gene of miR-223. Overexpression of miR-223 decreased expression of ARTN in KYSE150 cells while silencing miR-223 increased expression of ARTN in EC9706 cells. Furthermore, overexpression of miR-223 in KYSE150 cells decreased cell migration and invasion. Silencing of miR-223 in EC9706 cells increased cell migration and invasiveness. CONCLUSIONS: These results reveal that ARTN, a known tumor metastasis-related gene, is a direct target of miR-223 and that miR-223 may have a tumor suppressor function in esophageal carcinoma and could be used in anticancer therapies.

Expression and activity identification of a human nasopharyngeal carcinoma I50 anti-idiotype antibody.

OBJECTIVE: To obtain I50 anti-idiotype antibody and identify its activity in vitro. METHODS: I50 anti-idiotype (Id) antibody gene was amplified from the template of fuse 5-I50 by PCR to construct a prokaryotic expression vector pET25b-I50. The expression of pET25b-I50 in E. coli BL21(DE3) was induced by isopropylthio-ß-D-galactopyranoside (IPTG) and was confirmed by SDS-PAGE and Western blot with Ab1(FC2) monoclonal antibody and an anti-hexahistidine tag antibody. The method of dialysis refolding was used to restore the activity of I50 anti-Id antibody, which was measured by Dot-ELISA and lymphocyte proliferation assay. RESULTS: The recombinant vector was successfully constructed and the recombinant protein was successfully expressed and purified with 90% purity. The relative molecular weight of the expressed protein was 15 kD, which was in accordance with expectation. The activity of I50 anti-Id antibody could be restored and could promote the proliferation of lymphocyte in a dose-dependent manner. CONCLUSION: These results suggested that I50 anti-Id protein vaccine is likely an option in the therapy against nasopharyngeal carcinoma in vivo.

Expression of scFv SA3 against hepatoma fused with enhanced green fluorescent protein and its targeted ability in vivo.

OBJECTIVE: To express and purify the human scFv antibody, SA3, against the hepatoma fused to enhanced green fluorescent protein, and to observe the targeted capacity of fusion protein EGFP-SA3 in vivo. METHODS: SA3 and EGFP genes were cloned into plasmid pET-25b(+) to construct the recombinant plasmid EGFP-SA3/pET-25b(+), followed by DNA sequencing. Then it was transformed into E.coli BL21(DE3) and induced for fusion expression of EGFP-SA3 with IPTG. The expressed fusion protein EGFP-SA3 was purified and detected with SDS-PAGE. HepG2 cells were incubated with the fusion protein EGFP-SA3 in vitro, and the binding bioactivity was observed under the fluorescent microscope. Further more, we injected the EGFP-SA3 by caudal vein into nude mice planted by hepatoma and observed the whole body fluorescence image of EGFP. RESULTS: SA3 and EGFP genes were successfully cloned into pET-25b(+), which was confirmed by restriction enzyme NcoI-XhoI or NcoI-EcoRI. A band migrated at the position 750 bp, same to EGFP gene, emerged when recombinant plasmid was digested by restriction enzyme NcoI-EcoRI. Similarly, a band, about 1 500 bp, emerged when digested by NcoI-XhoI. The open-reading frame was confirmed by DNA sequencing. Fusion protein EGFP-SA3 was expressed as inclusion body. After purification and refolding, the result of immunofluorescence detection verified that EGFP-SA3 could specifically bind to HepG2 cells and maximum tumor penetration was at 24 h after the injection. CONCLUSION: The purified fusion protein EGFP-SA3 has strong binding capacity to HepG2 cells, indicating the scFv SA3 has a potential value as a targeting molecule for diagnosis and targeted therapy for liver cancer.

Prognostic and immunological significance of metastasis associated lung adenocarcinoma transcript 1 among different kinds of cancers.

LncRNAs belong to the type of noncoding RNA transcripts, which exceed 200 nucleotides in size. MALAT1 as one of the earlier identified lncRNAs in cancer is investigated by more and more scientific researchers. Expression, clinical significance and function of MALAT1 in pan-cancer exist as big difference. To detect the expression and clinical significance of MALAT1 gene precisely and comprehensively among different kinds of cancers, some classical databases such as GEPIA, TIMER, KM Plotter, and PrognoScan were fully applied. An immunological role of MALAT1 among different kinds of cancers was also determined in TIMER database. Our results showed that MALAT1 was differently expressed in different kinds of cancers using GEPIA, Oncomine, and TIMER databases to analyze. Especially, MALAT1 high RNA level was related to the early stage in lung and gastric cancer patients. MALAT1 expression was closely related to prognosis among different cancer patients. Furthermore, expression of MALAT1 was related to tumor immune cell infiltrating. Expression level of MALAT1 was also related to immune makers such as macrophage, T cell, NK cells, and so on. These findings indicate that MALAT1 could be a potential prognostic biomarker of some kinds of cancer and was significantly correlated with tumor-infiltrating immune cells in a wide variety of cancers.

Inhibition of ADP-ribosylation factor-like 6 interacting protein 1 suppresses proliferation and reduces tumor cell invasion in CaSki human cervical cancer cells.

ADP-ribosylation factor-like 6 interacting protein 1 (ARL6IP1) is an apoptotic regulator. To investigate the role of ARL6IP1 in human cervical cancer progression, we designed and used short hairpin RNA (shRNA) to inhibit ARL6IP1 expression in CaSki cells and validated its effect on cell proliferation and invasion. Changes in gene expression were analyzed by reverse transcriptase-polymerase chain reaction (RT-PCR) or western blot. Down-regulation of ARL6IP1 expression by infection with ARL6IP1-specific RNAi-expressing vector inhibited CaSki cell proliferation and colony formation. In addition, down-regulation of ARL6IP1 expression arrested CaSki cell cycling at the G0/G1 phase and mitigated CaSki cell migration, determined by wound healing assays. ARL6IP1 was involved in cervical cancer cell growth, cell cycle progression, and invasion through regulation of gene expression, such as Caspase-3, Caspase-9, p53, TAp63, NF-κB, MAPK, Bcl-2, and Bcl-xL, suggesting that ARL6IP1 could have important implications in cervical cancer biology. Our findings illustrate the biological significance of ARL6IP1 in cervical cancer progression, and provide novel evidence that ARL6IP1 may serve as a therapeutic target in the prevention of human cervical cancer.

Inhibition of metastasis-associated lung adenocarcinoma transcript 1 in CaSki human cervical cancer cells suppresses cell proliferation and invasion.

Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is suggested to be a long (~7 kb) non-coding RNA. MALAT1 is overexpressed in many human carcinomas, but its function remains unknown. To investigate the role of MALAT1 in human cervical cancer progression, we designed and used short hairpin RNA to inhibit MALAT1 expression in CaSki cells and validated its effect on cell proliferation and invasion. Changes in gene expression were analyzed by reverse transcriptase- polymerase chain reaction. Our data demonstrated that MALAT1 was involved in cervical cancer cell growth, cell cycle progression, and invasion through the regulation of gene expression, such as caspase-3, -8, Bax, Bcl-2, and BclxL, suggesting that MALAT1 could have important implications in cervical cancer biology. Our findings illustrate the biological significance of MALAT1 in cervical cancer progression and provide novel evidence that MALAT1 may serve as a therapeutic target in the prevention of human cervical cancer.

Exosome-based targeted RNA delivery for immune tolerance induction in skin transplantation.

Exosomes have been widely applied to the delivery of RNA and small molecules currently. However, the low targeting and specificity greatly limited the effect of exosome delivery. Here we designed an exosome that can perform the targeted delivery of two different types of RNA. Based on the mesenchymal stem cells (MSCs) derived exosomes, the RNA delivery system of targeted dendritic cells (DC-Exosome) was constructed, using the layer by layer self-assembly. DC-Exosomes can specifically bind to DCs, while guiding the endocytosis of chimeras and exosome. Then aptamer/siRNA chimera was cut into mTOR siRNA by Dicer, and microRNA was released from exosome under lysosomal digestion. SIGN aptamer performed the rapid induction of immune tolerance, and later mTOR siRNA was formed to inhibit mTOR pathway and suppress immune responses. Exosomes could maintain long time-stability after PEG-PEI polyplexes modification and promote HLA-G expression in DCs continuously. Animal experiments showed that DC-Exosomes could induce immune tolerance at 3, 7, and 14 days after skin transplantation. Compared with the microRNA-Exosome group, the number of CD11c+ DCs in DC-Exosome group decreased, while the proportion of HLA-G+ DCs increased remarkably. In conclusion, we constructed a new exosome-based targeted delivery system which could effectively induce the immune tolerance in transplantation.

Recent BCR stimulation induces a negative autoregulatory loop via FBXO10 mediated degradation of HGAL.

Regulating B-cell receptor (BCR) signaling after antigenic stimulation is essential to properly control immune responses. Currently known mechanisms of inhibiting BCR signaling are via co-receptor stimulation and downstream immunoreceptor tyrosine-based inhibition motif (ITIM) phosphorylation. Herein we demonstrate that BCR stimulation induces rapid and reversible palmitoylation of the SCF-FBXO10 ubiquitin E3 ligase. This results in FBXO10 relocation to the cell membrane, where it targets the human germinal center-associated lymphoma (HGAL) protein for ubiquitylation and degradation, leading to decreases in both BCR-induced calcium influx and phosphorylation of proximal BCR effectors. Importantly, FBXO10 recognition and degradation of HGAL is phosphorylation independent and instead relies on a single evolutionarily conserved HGAL amino acid residue (H91) and FBXO10 relocalization to the cytoplasmic membrane. Together our findings demonstrate the first evidence of negative BCR signaling regulation from direct BCR stimulation and define the temporospatial functions of the FBXO10-HGAL axis. FBXO10 is infrequently mutated in DLBCL but some of these mutations deregulate BCR signaling. These observations may have important implications on lymphomagenesis and other immune processes.