Splicing factor proline- and glutamine-rich regulates cytotoxic T lymphocytes-mediated cytotoxicity on non-small cell lung cancer by directly binding to PD-L1 3'UTR.

Splicing factor proline- and glutamine-rich (SFPQ) can interact with RNAs to regulate gene expression. The function of SFPQ in the immunotherapy of non-small cell lung cancer (NSCLC) is investigated in this study. H1299 and A549 cells were transfected with shSFPQ plasmid. Cell counting kit-8 (CCK-8) and cell clone formation were utilized to detect survival and proliferation. Programmed death-ligand 1 (PD-L1) and SFPQ were detected in NSCLC patients treated with anti-PD-L1 antibody. Dual-luciferase assays, RNA immunoblotting, RNA pull-down, and mRNA stability assay were applied to verify the regulation of PD-L1 with SFPQ. Human peripheral blood mononuclear cells (PBMC)-derived dendritic cells were loaded with irradiated A549 and H1299 cells, which were cultured with autologous CD8+T cells and tumor cells to perform in vitro tumor-specific cytotoxic T lymphocytes (CTL) cytotoxicity analysis. SFPQ silencing inhibited the survival and proliferation of H1299 and A549 cells with down-regulated PD-L1 expression. PD-L1 and SFPQ expression were markedly higher in anti-PD-L1 antibody treatment responders compared to non-responders, which showed a positive Pearson correlation (R = 0.76, P < .001). SFPQ up-regulated the relative mRNA and protein expression of PD-L1 by binding to the PD-L1 3'UTR to slow the decay of PD-L1 mRNA. SFPQ silencing promoted the killing effect of CTL on A549 and H1299 cells. SFPQ up-regulates PD-L1 expression by binding with PD-L1 3'UTR to slow the decay of PD-L1 mRNA, and SFPQ silencing promotes CTL-mediated cytotoxicity on NSCLC cells.

LNX2 involves in the role of ghrelin to promote the neuronal differentiation of adipose tissue-derived mesenchymal stem cells.

Adipose tissue-derived mesenchymal stem cells (ADSCs) have promising effects on nerve repair due to the differentiation ability to neural cells. Ghrelin has been shown to promote the neural differentiation of ADSCs. This work was designed to explore its underlying mechanism. Herein, we found high expression of LNX2 in ADSCs after neuronal differentiation. Knockdown of LNX2 might block neuronal differentiation of ADSCs, as evidenced by the decreased number of neural-like cells and dendrites per cell, and the reduced expressions of neural markers (including ß-Tubulin III, Nestin, and MAP2). We also demonstrated that LNX2 silencing suppressed the nuclear translocation of ß-catenin in differentiated ADSCs. Luciferase reporter assay indicated that LNX2 inhibited wnt/ß-catenin pathway by reducing its transcriptional activity. In addition, results showed that LNX2 expression was increased by ghrelin, and its inhibition diminished the effects of ghrelin on neuronal differentiation. Altogether, the results suggest that LNX2 is involved in the role of ghrelin to facilitate neuronal differentiation of ADSCs.

Amplified LncRNA PVT1 promotes lung cancer proliferation and metastasis by facilitating VEGFC expression.

Although the abundance of long non-coding RNA (lncRNA) plasmacytoma variant translocation 1 (PVT1) in lung cancer has been well researched, the underlying mechanisms behind its effects were unknown. Here we investigated the molecular events regulating PVT1 in lung cancer. The pro-proliferative property of PVT1 was examined using a xenograft tumor model. Transwell chambers were used to analyze the impact of PVT1 expression on cell invasiveness and migration. In vivo metastasis was examined by tail-vein-injection in mice. Direct binding of miR-128 to PVT1 was investigated using a probe pulldown assay. The relative expression levels of miR-128 and PVT1 were quantified by real-time polymerase chain reaction and Western blotting. We show here that when PVT1 is amplified, there is a poor survival prognosis for patients with lung cancer. Elevated levels of PVT1 promoted lung cancer cell proliferation and metastasis, both in vitro and in vivo. Mechanistically, we found that PVT1 competes endogenously with miR-128 in the regulation of vascular endothelial growth factor C (VEGFC) expression, which is significantly associated with an unfavorable prognosis in lung cancer. We identified that copy number amplification significantly contributes to the high level of PVT1 transcripts in lung cancer, which promotes cell proliferation and metastatic behavior via modulating VEGFC expression by endogenous competition with miR-128.

Ghrelin promotes neural differentiation of adipose tissue-derived mesenchymal stem cell via AKT/mTOR and ß-catenin signaling pathways.

Adipose tissue-derived mesenchymal stem cells (ADSCs) are multipotent cells that can differentiate into various cell types. This study aimed to investigate the effect of ghrelin on the neural differentiation of rat ADSCs and underlying molecular mechanisms. Rat ADSCs were isolated and third-passage ADSCs were used in this study. The isolated ADSCs were characterized by flow cytometry analysis for MSCs' surface expression markers as evidenced by positive for CD90, CD44, and CD29 and negative for CD34, CD45, and CD11b/2f/c. The multilineage differentiation of ADSCs was confirmed by adipogenic, osteogenic, and neural differentiation. After induction of neurogenesis, the differentiated cells were identified by development of neuron-like morphology and expression of neural markers including glial fibrillary acidic protein, Nestin, MAP2, and ß-Tubulin III using immunofluorescence and western blot. Ghrelin concentration dependently elevated the proportion of neural-like cells and branching dendrites, as well as upregulated the expression of neural markers. Further, the expression of nuclear ß-catenin, p-GSK-3ß, p-AKT, and p-mTOR was increased by ghrelin, indicating an activation of ß-catenin and AKT/mTOR signaling after the ghrelin treatment. Importantly, inhibition of ß-catenin or AKT/mTOR signaling suppressed ghrelin-induced neurogenesis. Therefore, we demonstrate that ghrelin promotes neural differentiation of ADSCs through the activation of ß-catenin and AKT/mTOR signaling pathways.

Upregulation of circular RNA circ_0001721 predicts unfavorable prognosis in osteosarcoma and facilitates cell progression via sponging miR-569 and miR-599.

Osteosarcoma (OS) is the most frequent bone malignancy in human. Growing evidence suggests that circular RNAs (circRNAs) play a significant role in regulating tumorigenesis and progression. Previously, circ_0001721 was identified upregulated in OS tissues screened by circRNA microarrays. In the current study, circ_0001721 expression in OS tissue samples and cells were measured by qRT-PCR. Its clinical value was also explored. For the part of functional assays, CCK-8, clone-forming, flow cytometric, Transwell, xenograft assays were performed. Dual luciferase reporter assays were used to examine the mechanism of circ_0001721. We found that circ_0001721 was enhanced in OS tissue samples and cell lines and the overexpression of circ_0001721 is closely related to clinical severity. In addition, circ_0001721 may be used as a prognostic indicator for OS patients. What's more, loss-of-function and gain-of-function assays demonstrated circ_0001721 facilitates cell progression in OS. Circ_0001721 could sponge miR-569 and miR-599. The oncogenic properties of circ_0001721 is partly attributed to its repression on miR-569 and miR-599. Collectively, the present data reveal the participation of circ_0001721 in tumorigenesis of OS cells, and may indicate a novel therapeutic target.

miRNA-556-3p promotes human bladder cancer proliferation, migration and invasion by negatively regulating DAB2IP expression.

MicroRNAs (miRNAs) play critical roles in tumorigenesis and metastasis by negatively regulating gene expression through complementary binding to the 3'-untranslated region of target mRNAs. The role of miRNAs in expression of the tumor suppressor DAB2IP in bladder cancer (BC) remains unknown. The aim of the present study was to identify miRNAs targeting DAB2IP and determine their expression and function in BC. We predicted candidate miRNAs targeting DAB2IP using TargetScan software. Dual-luciferase reporter assays confirmed that miRNA-556-3p directly regulated DAB2IP expression. Quantitative RT-PCR and RNase protection assays showed that endogenous miRNA-556-3p expression was significantly upregulated in clinical samples of BC patients and BC cell lines and western blot analysis indicated that DAB2IP expression in BC tissues and BC cell lines was concurrently downregulated. Gain or loss of function studies showed that upregulation of miRNA-556-3p promoted proliferation, invasion, migration and colony formation of BC cells, whereas downregulation resulted in opposite effects. Importantly, restoration of DAB2IP expression rescued the effects induced by miRNA-556-3p. Overexpression of miRNA-556-3p in BC cells not only decreased DAB2IP expression, but also markedly increased Ras GTPase activity and ERK1/2 phosphorylation level. These findings suggest that DAB2IP is a direct target of miRNA-556-3p, and endogenous miRNA-556-3p expression shows inverse correlation with simultaneous DAB2IP expression in BC tissues and cells. miRNA-556-3p functions as a tumor promoter in tumorigenesis and metastasis of BC by targeting DAB2IP. Moreover, miRNA-556-3p-mediated DAB2IP suppression plays an oncogenic role by partial activation of the Ras-ERK pathway.

Regulation of BGC-823 cell sensitivity to adriamycin via miRNA-135a-5p.

MicroRNAs (miRNAs) play an important role in the genesis and development of gastric cancer. In the present study, we determined whether miRNA-135a-5p expression was increased in gastric cancer compared with adjacent non-tumor tissues using 20 pairs of gastric cancer and para-carcinoma tissue samples which were assessed via microarray and bioinformatics analysis, and western blotting. The protein content detection showed that miRNA­135a-5p expression was inversely correlated with AP-2α. Bioinformatics analysis revealed that AP-2α contains a putative miRNA-135a-5p target, which was confirmed as a direct target using the 3'-UTR luciferase reporter system. Additionally, an increase and decrease of miRNA-135a-5p inhi-bited or impaired adriamycin-induced apoptosis in BGC-823 cells (p<0.05, compared with the group without gene intervention), respectively. Luciferase reporter experiments confirmed that AP-2α bound to the BCL-2 promoter and affected its transcription. Therefore, miRNA-135a-5p increased BCL-2 via AP-2α and consequently enhanced cell resistance to apoptosis. This newly identified miRNA-135a-5p-AP-2α-BCL-2 pathway provides insight for the treatment of gastric cancer and solution for insensitivity of gastric cancer to chemotherapy drugs.

microRNA-128 plays a critical role in human non-small cell lung cancer tumourigenesis, angiogenesis and lymphangiogenesis by directly targeting vascular endothelial growth factor-C.

Recent studies have indicated that microRNAs (miRNAs) are important gene regulators that play critical roles in biological processes and function as either tumour suppressors or oncogenes. Therefore, the expression levels of miRNAs can be important and reliable biomarkers for cancer detection and prognostic prediction, and potentially serve as targets for cancer therapy. In this study, we showed that the expression level of miR-128 was significantly downregulated in non-small cell lung cancer (NSCLC) tissues and cancer cells, and was significantly correlated with NSCLC differentiation, pathological stage and lymph node metastasis. Ectopic miR-128 overexpression significantly suppressed in vitro proliferation, colony formation, immigration and invasion, and induced G1 arrest and apoptosis of NSCLC cells. Interestingly, ectopic miR-128 overexpression could significantly inhibit vascular endothelial growth factor (VEGF)-C expression and reduce the activity of a luciferase reporter containing the VEGF-C 3'-untranslated region. In addition, overexpression of miR-128 in NSCLC cells and human umbilical vein endothelial cells (HUVECs) cells led to decreased expression of VEGF-A, vascular endothelial growth factor receptor (VEGFR)-2 and VEGFR-3, critical factors responsible for cancer angiogenesis and lymphangiogenesis, and subsequently decreased phosphorylation of extracellular signal-regulated kinase (ERK), phosphatidylinositol 3-kinase (AKT) and p38 signalling pathways. Furthermore, in vivo restoration of miR-128 significantly suppressed tumourigenicity of A549 cells in nude mice and inhibited both angiogenesis and lymphangiogenesis of tumour xenografts. These findings suggest that miR-128 could play a role in NSCLC tumourigenesis at least in part by modulation of angiogenesis and lymphangiogenesis through targeting VEGF-C, and could simultaneously block ERK, AKT and p38 signalling pathways. Therapeutic strategies to restore miR-128 in NSCLC could be useful to inhibit tumour progression.

Lentivirus-mediated RNAi knockdown of NUPR1 inhibits human nonsmall cell lung cancer growth in vitro and in vivo.

NUPR1 (nuclear protein 1) was found to play a key role in the development of several malignancies including pancreas, breast, and prostate cancers. However, the functional role of NUPR1 in nonsmall cell lung cancer (NSCLC) progression and development is little known. Here, lentivirus-mediated small interfering RNA (siRNA) was employed to downregulate endogenous NUPR1 expression to study the function of NUPR1 in growth of nonsmall cell lung cancer. A lentivirus-mediated RNAi technology was used to specifically knock down the expression of NUPR1 in H1299 cells. Quantitative real-time reverse transcriptase polymerase chain reaction, flow cytometry, western blot and cell count assays were studied to characterize NUPR1 expression in vitro. Furthermore, nonsmall cell lung cancer xenograft models in nude mice were established to investigate whether knockdown of NUPR1 reduces the tumor growth in vivo. We found that downregulation of NUPR1 expression significantly inhibited nonsmall cell lung cancer H1299 cells proliferation and colony formation in vitro. Moreover, the specific downregulation of NUPR1 arrested cells in G0 phase of cell cycle and increased apoptosis rate. Silencing of NUPR1 also suppressed tumor growth by tail vein injection of lentivirus encoded shRNA against NUPR1 in vivo. Our findings revealed that the NUPR1 gene represents a promising target for gene silencing therapy in nonsmall cell lung cancer.