OBJECTIVES: To explore the mechanism by which histone deacetylase 1 (HDAC1) regulates steroid-induced apoptosis of mouse osteocyte-like MLO-Y4 cells. METHODS: MLY-O4 cells were treated with 400 nmol/L trichostatin A (TSA) or 1 mmol/L dexamethasone for 24 h or transfected with a HDAC1-overexpressing vector prior to TSA or dexamethasone treatment. The changes in the expressions of HDAC1, SP1, cleaved caspase-3 and Bax, SP1 acetylation level, cell proliferation, and cell apoptosis were examined. The interaction between HDAC1 and SP1 was determined with immunoprecipitation assay and Western blotting. RESULTS: Treatment with dexamethasone significantly increased cell apoptosis, enhanced the expressions of cleaved caspase-3 and Bax, reduced HDAC1 expression, and suppressed proliferation of MLO-Y4 cells. Both TSA and dexamethasone obviously increased SP1 acetylation level and the expression of SP1 in MLO-Y4 cells. HDAC1 overexpression in the cells significantly attenuated the effect of TSA and dexamethasone, promoted cell proliferation, lowered the expressions of SP1, cleaved caspase-3 and Bax, and inhibited dexamethasone-induced cell apoptosis. Immunoprecipitation assay and Western blotting demonstrated the interaction between HDAC1 and SP1 in the cells. CONCLUSIONS HDAC1 inhibits dexamethasone-induced apoptosis and promotes proliferation of cultured mouse osteocytes by suppressing SP1 expression via promoting its deacetylation.
Animals ; Apoptosis/drug effects* ; Mice ; Histone Deacetylase 1/genetics* ; Osteocytes/drug effects* ; Sp1 Transcription Factor/metabolism* ; Acetylation ; Dexamethasone/pharmacology* ; Cell Proliferation/drug effects* ; Caspase 3/metabolism* ; Cell Line ; Hydroxamic Acids/pharmacology* ; bcl-2-Associated X Protein/metabolism*

OBJECTIVES: To investigate the mechanism mediating the regulatory effect of miR-155-5p on proliferation of human submandibular gland epithelial cells (HSGECs) in primary Sjogren's syndrome (pSS). METHODS: Dual luciferase reporter assay was used to verify the targeting relationship between miR-155-5p and the PI3K/AKT pathway. In a HSGEC model of pSS induced by simulation with TRAIL and INF-γ, the effects of miR-155-inhibitor-NC or miR-155 inhibitor on cell viability, cell cycle, apoptosis and proliferation were evaluated using CKK8 assay, flow cytometry and colony formation assay. ELISA and RT-PCR were used to detect the expressions of inflammatory cytokines and miR-155-5p mRNA in the cells; Western blotting was performed to detect the expressions of proteins in the PI3K/AKT signaling pathway. RESULTS: Dual luciferase assay showed that miR-155-5p targets the PI3K/AKT pathway via PIK3R1 mRNA. The HSGEC model of pSS showed significantly decreased cell viability, cell clone formation ability and expressions IL-10 and IL-4 and increased cell apoptosis, cell percentage in G2 phase, expressions of TNF‑α, IL-6, miR-155-5p and PIK3R1 mRNA, p-PI3K/PI3K ratio, p-Akt/AKT ratio, and PIK3R1 protein expression. Treatment of the cell models with miR-155 inhibitor significantly increased the cell viability, G1 phase cell percentage, colony formation ability, and expressions of IL-10 and IL-4 levels, and obviously reduced cell apoptosis rate, G2 phase cell percentage, expressions of TNF-α, IL-6, miR-155-5p and PIK3R1 mRNA, p-PI3K/PI3K ratio, p-AKT/AKT ratio, and PIK3R1 protein expression. CONCLUSIONS In HSGEC model of pSS, inhibition of miR-155-5p can promote cell proliferation and reduced cell apoptosis by targeting PI3K1 mRNA to negatively regulate the overexpression of PI3K/AKT signaling pathway.
Humans ; MicroRNAs/genetics* ; Cell Proliferation ; Signal Transduction ; Proto-Oncogene Proteins c-akt/metabolism* ; Sjogren's Syndrome/pathology* ; Epithelial Cells/cytology* ; Submandibular Gland/cytology* ; Phosphatidylinositol 3-Kinases/metabolism* ; Apoptosis ; Class Ia Phosphatidylinositol 3-Kinase ; Cells, Cultured

OBJECTIVES: To investigate the clinical significance of SLC1A5 overexpression in pan-cancer and its mechanism for promoting hepatocellular carcinoma (HCC) progression. METHODS: We analyzed the correlation of SLC1A5 expression with clinical stage, lymph node metastasis and prognosis in pan-cancer using TCGA and ICGC datasets and explored its association with immune cell infiltration using EPIC, CIBERSORT, and TIMER algorithms. In HCC cell lines, the effects of lentivirus-mediated SLC1A5 overexpression or RNA interference on cell proliferation were examined using CCK-8 assay, and the growth of HCC cell xenografts overexpressing SLC1A5 was observed in nude mice. The effects of SLC1A5 overexpression or silencing in HCC cells on macrophage polarization were evaluated in a cell co-culture system. RESULTS: SLC1A5 was mainly localized on cell membrane and was highly expressed in most cancers in association with clinical stage, lymph node metastasis and poor prognosis. SLC1A5 expression was positively correlated with immunity score in 13 cancer types, especially in low-grade glioma (LGG), LIHC and thyroid cancer. SLC1A5 was positively correlated with macrophage infiltration level in LGG and LIHC but negatively correlated with macrophage infiltration in 5 cancers including lung squamous carcinoma, pancreatic carcinoma, and gastric carcinoma. Patients with SLC1A5 overexpression and high level of M2 macrophage infiltration had the worst survival outcomes. SLC1A5 was correlated with immunosuppression-related genes, cytokines, and cytokine receptors, which was the most obvious in LGG and LIHC. SLC1A5 was highly expressed in different HCC cell lines, and its overexpression promoted HCC cell proliferation both in vitro and in nude mice. In the cell co-culture experiment, SLC1A5 was positively correlated with the molecular markers of M2 polarization of macrophages, and its overexpression strongly promoted M2 polarization of the macrophages and inhibited T cell secretion of IFN-γ. CONCLUSIONS SLC1A5 expression level is correlated with clinical stage, lymph node metastasis, prognosis, and immune cell infiltration in most cancers, and its overexpression promotes HCC progression by inhibiting T-cell function via promoting M2 polarization of macrophages.
Humans ; Carcinoma, Hepatocellular/metabolism* ; Liver Neoplasms/metabolism* ; Animals ; Macrophages/cytology* ; Disease Progression ; Cell Line, Tumor ; Mice ; Amino Acid Transport System ASC/genetics* ; Cell Proliferation ; Lymphatic Metastasis ; Mice, Nude ; Prognosis ; Minor Histocompatibility Antigens

OBJECTIVES: To identify potential molecular targets of quercetin in the treatment of clear cell renal carcinoma (ccRCC). METHODS: The therapeutic targets of quercetin were screened from multiple databases by network pharmacology analysis, and the targets significantly correlated with ccRCC were screened from 4907 plasma proteins using a Mendelian randomization method. The drug-disease network model was constructed to screen the potential key targets. The functions of these targets were evaluated via bioinformatics analysis, and the screened targets were verified in cultured ccRCC cells. RESULTS: Network pharmacology analysis combined with Mendelian randomization identified TP53 (OR=3.325, 95% CI: 1.805-6.124, P=0.0001), ARF4 (OR=0.173, 95% CI: 0.065-0.456, P=0.0003), and DPP4 (OR=0.463, 95% CI: 0.302-0.711, P=0.0004) as the core targets in quercetin treatment of ccRCC. Bioinformatics analysis showed that TP53 was highly expressed in ccRCC, and patients with high TP53 expressions had worse survival outcomes. Molecular docking studies showed that the binding energy between quercetin and TP53 was -5.83 kcal/mol. In cultured 786-O cells, CCK-8 assay and wound healing assay showed that treatment with quercetin significantly inhibited cell proliferation and migration. Quercetin treatment also strongly suppressed the expression of TP53 at both the mRNA and protein levels in 786-O cells as shown by RT-qPCR and Western blotting. CONCLUSIONS TP53 may be the key target of quercetin in the treatment of ccRCC, which sheds light on potential molecular mechanism that mediate the therapeutic effect of quercetin.
Humans ; Quercetin/pharmacology* ; Carcinoma, Renal Cell/genetics* ; Cell Proliferation/drug effects* ; Kidney Neoplasms/genetics* ; Cell Movement/drug effects* ; Tumor Suppressor Protein p53/metabolism* ; Cell Line, Tumor ; Computational Biology

OBJECTIVES: To investigate the regulatory effect of LINC00837/miR-671-5p/SERPINE2 functional axis on pathological processes of fibroblast-like synovial cells (FLS) in rheumatoid arthritis (RA). METHODS: RA-FLS were transfected with a LINC00837 overexpression plasmid (pcDNA3.1-LINC00837), a LINC00837 interference plasmid (siRNA-LINC00837), or their respective negative control plasmids (pcDNA3.1-NC and siRNA-NC). Dual luciferase was used to verify the targeting relationship between LINC00837 and miR-671-5p and between miR-671-5p and SERPINE2. RT-qPCR was used to detect the expression levels of LINC00837, miR-671-5p and SERPINE2 in normal FLS or the transfected cells, whose proliferation and migration abilities were assessed using Edu assay and scratch healing assay and by detecting the expression levels of Ki-67, PCNA, E-cadherin and N-cadherin with Western blotting. The changes in cellular secretion of the inflammatory cytokines (TNF‑α, IL-17, IL-4 and IL-10) were examined using ELISA. RESULTS: Dual luciferase reporter gene assay showed that LINC00837 was capable of binding to the 3'-UTR of miR-671-5p, and the latter bound to the 3-UTR of SERPINE2 at specific binding sites between them. Compared with normal FLS, RA-FLS showed significantly increased expressions of LINC00837 and SERPINE2, lowered miR-671-5p expression and enhanced proliferation and migration abilities with increased expressions of pro-inflammatory cytokines and reduced expressions of anti-inflammatory cytokines. Transfection of RA-FLS with pcDNA-LINC00837 further enhanced cell proliferation and migration and the changes in the inflammatory cytokines, while transfection with si-LINC00837 produced the opposite changes. CONCLUSIONS RA-FLS have a LINC00837/miR-671-5p/SERPINE2 functional axis, which regulates cell proliferation, migration and secretion of inflammatory factors, and interventions targeting LINC00837 may provide a potential strategy to regulate the pathological processes in RA-FLS.
Arthritis, Rheumatoid/metabolism* ; MicroRNAs/metabolism* ; Humans ; Cell Proliferation ; Cell Movement ; Synovial Membrane/pathology* ; RNA, Long Noncoding/genetics* ; Fibroblasts/metabolism* ; Synoviocytes/metabolism* ; Cells, Cultured ; Transfection

OBJECTIVES: To investigate the role of METTL3 and FOXO3 in anthracycline resistance in acute myeloid leukemia (AML) cells. METHODS: Methylated RNA immunoprecipitation sequencing (MeRIP-seq) and transcriptome sequencing (RNA-seq) were performed in anthracycline-resistant and sensitive HL60 and K562 cells with lentivirus-mediated knockdown or overexpression of METTL3 and FOXO3. TCGA and GSE6891 datasets were used for analysis of the clinical and gene expression data of AMI patients. FOXO3 expressions at the mRNA and protein levels in the transfected cells were detected with RT-qPCR and Western blotting, and the changes in cell proliferation and apoptosis were evaluated using CCK8 assay and flow cytometry; the expression of m⁶A-modified mRNA and mRNA stability of FOXO3 was detected analyzed using MeRIP-qPCR and RT-qPCR. Functional enrichment analysis of the differential genes in the transfected cells was performed. RESULTS: Differential gene analysis in anthracycline-resistant versus sensitive AML cells and in cells with METTL3 knockdown revealed the enrichment in FoxO and autophagy pathways (P<0.05), and the anthracycline-resistant cells showed significantly increased m⁶A modification of FOXO3. FOXO3 expression was positively correlated with METTL3 expression. METTL3 knockdown significantly reduced FOXO3 mRNA stability and its protein levels in anthracycline-resistant AML cells, which exhibited higher m6A-modified FOXO3 expression levels than their sensitive counterparts. Database analysis, Kaplan-Meier analysis and RT-qPCR results suggested that a high FOXO3 expression was associated with a poor prognosis of AML patients. In anthracycline-resistant AML cells expressing higher FOXO3 levels than the sensitive cells, lentivirus-mediated overexpression of FOXO3 significantly enhanced cell proliferation and suppressed cell apoptosis. Inhibiting autophagy using an autophagy inhibitor (Baf.A1) obviously enhanced the inhibitory effect of adriamycin on resistant AMI cells and cells overexpressing FOXO3. CONCLUSIONS METTL3 promotes FOXO3 expression via m6A modification, and FOXO3-driven autophagy contributes to anthracycline resistance in AML cells by enhancing cell proliferation and suppressing cell apoptosis.
Humans ; Forkhead Box Protein O3/genetics* ; Leukemia, Myeloid, Acute/genetics* ; Drug Resistance, Neoplasm ; Methyltransferases/genetics* ; Autophagy ; Anthracyclines/pharmacology* ; HL-60 Cells ; Apoptosis ; Cell Proliferation ; K562 Cells

OBJECTIVES: To explore the expression of hexokinase 2 (HK2) in colorectal cancer (CRC) and its possible mechanisms for regulating tumor cell behaviors and tumor immune microenvironment. METHODS: We analyzed HK2 expression in CRC and its impact on patient prognosis and tumor immune microenvironment using public databases. HK2 expression was also examined in 8 CRC and paired adjacent tissues using immunohistochemistry, Western blotting and RT-qPCR. In cultured CRC cell lines CT26 and HCT116 with low HK2 expression, the effects of lentivirus-mediated HK2 overexpression and JAK/STAT3 inhibitors on cell proliferation, migration, and invasion were assessed using CCK-8 assay, colony formation assay and Transwell assay and in a subcutaneous tumor-bearing mouse model; the changes were also observed in MC38 and CACO2 cells with high HK2 expressions following treatment with HK2 inhibitor 3-BP. Western blotting was performed to verify the relationship between HK2 and JAK/STAT signaling pathway protein expressions. RESULTS: Informatics analyses suggested that HK2 expression was significantly higher in CRC tissues than in adjacent tissues (P<0.001), and patients with high HK2 expressions had worse prognosis (P=0.09). In the 8 clinical CRC tissues, HK2 expressions were significantly higher in the tumor tissues than in the adjacent tissues (P<0.01). In CT26 and HCT116 cells, HK2 overexpression significantly enhanced cell proliferation, migration and invasion, while in HK2-overexpressing MC38 and CACO2 cells, inhibiting HK2 with 3-BP strongly suppressed these changes. HK2 overexpression promoted STAT3 phosphorylation, and JAK/STAT3 inhibitors effectively suppressed tumor cell proliferation, migration and invasion. TIMER and MCPcounter analyses indicated correlations between HK2 and immune cells, and TCGA and GEO analyses suggested significant positive correlations between HK2 and the immune checkpoints including PDCD1. CONCLUSIONS HK2 is upregulated in CRC to promote tumor cell proliferation, migration and invasion possibly by activating the JAK-STAT signaling pathway and modulating tumor immune microenvironment.
Humans ; Colorectal Neoplasms/metabolism* ; Cell Proliferation ; Hexokinase/genetics* ; Tumor Microenvironment ; Cell Movement ; Signal Transduction ; Animals ; STAT3 Transcription Factor/metabolism* ; Mice ; Neoplasm Invasiveness ; Cell Line, Tumor ; Janus Kinases/metabolism* ; HCT116 Cells ; Caco-2 Cells

OBJECTIVES: To investigate CEACAM6 expression in nasopharyngeal carcinoma (NPC) and its regulatory effects on tumor cell proliferation, migration, and epithelial-mesenchymal transition (EMT). METHODS: CEACAM6 expression in NPC was analyzed using GEO datasets and validated by immunohistochemistry in NPC tissues and by Western blotting and RT-qPCR in NPC cell lines (HNE1, C666-1, HK1, 5-8F and CNE2Z) and normal nasopharyngeal epithelial NP69 cells. In the NPC cell lines, the effects of lentivirus-mediated CEACAM6 overexpression and knockdown on cell proliferation, migration, invasion and cytoskeletal structures were evaluated using CCK-8 assay, Edu staining, wound healing assay, Transwell assay, and phalloidin staining. Western blotting was performed to determine the expressions of EMT-related proteins (FN1, ITGA5, ITGB1, E-cadherin, N-cadherin and vimentin) in the NPC cells and the effect of FN1 overexpression on ITGA5 and ITGB1 protein expressions. RESULTS: Analysis of the data from the GEO datasets suggested that CEACAM6 was significantly downregulated in NPC, which was associated with poor patient prognosis. Immunohistochemistry also showed low expressions of CEACAM6 in clinical NPC tissues (P<0.05). In NPC cells, CEACAM6 overexpression significantly suppressed cell proliferation, migration and invasion and reduced the fluorescence intensity of actin. CEACAM6 overexpression also resulted in significant downregulation of FN1, ITGA5, ITGB1, N-cadherin and vimentin expressions and upregulation of E-cadherin expression, and FN1 overexpression obviously attenuated the inhibitory effect of CEACAM6 overexpression on ITGA5 and ITGB1 expressions. CONCLUSIONS CEACAM6 inhibits NPC cell migration and invasion by inhibiting EMT via regulating FN1, ITGA5 and ITGB1 expressions.
Humans ; Epithelial-Mesenchymal Transition ; Cell Movement ; Cell Proliferation ; Nasopharyngeal Carcinoma ; Nasopharyngeal Neoplasms/metabolism* ; Cell Line, Tumor ; Cell Adhesion Molecules/genetics* ; Antigens, CD/metabolism* ; GPI-Linked Proteins ; Integrin alpha5/metabolism* ; Integrin beta1/metabolism* ; Cadherins/metabolism* ; Fibronectins ; Integrins

OBJECTIVES: To analyze MYO1B expression in gastric cancer, its association with long-term prognosis and its role in regulating biological behaviors of gastric cancer cells. METHODS: We analyzed MYO1B expression in gastric cancer and its correlation with tumor grade, tumor stage, and patient survival using the Cancer Public Database. We also examined MYO1B expression with immunohistochemistry in gastric cancer and paired adjacent tissues from 105 patients receiving radical surgery and analyzed its correlation with cancer progression and postoperative 5-year survival of the patients. GO and KEGG enrichment analyses were used to explore the biological functions of MYO1B and the key pathways. In cultured gastric cancer cells, we examined the changes in cell proliferation, migration and invasion following MYO1B overexpression and knockdown. RESULTS: Data from the Cancer Public Database showed that MYO1B expression was significantly higher in gastric cancer tissues than in normal tissues with strong correlations with tumor grade, stage and patient prognosis (P<0.05). In the clinical tissue samples, MYO1B was significantly overexpressed in gastric cancer tissues in positive correlation with Ki67 expression (r=0.689, P<0.05) and the parameters indicative of gastric cancer progression (CEA ≥5 μg/L, CA19-9 ≥37 kU/L, G3-4, T3-4, and N2-3) (P<0.05). Kaplan-Meier analysis and multivariate Cox regression analysis suggested that high MYO1B expression was associated with decreased postoperative 5-year survival and was an independent risk factor (HR: 3.522, 95%CI: 1.783-6.985, P<0.05). MYO1B expression level was a strong predictor of postoperative survival (cut-off value: 3.11, AUC: 0.753, P<0.05). GO and KEGG analyses suggested that MYO1B may regulate cell migration and the mTOR signaling pathway. In cultured gastric cancer cells, MYO1B overexpression significantly enhanced cell proliferation, migration, and invasion and promoted the phosphorylation of Akt and mTOR. CONCLUSIONS High MYO1B expression promotes proliferation, migration and invasion of gastric cancer cells and is correlated with poor patient prognosis.
Humans ; Stomach Neoplasms/metabolism* ; Cell Proliferation ; Prognosis ; Cell Movement ; Myosin Type I/genetics* ; Neoplasm Invasiveness ; Cell Line, Tumor ; Female ; Male

OBJECTIVES: To elucidate the molecular mechanism by which villin-like protein VILL (VILL) inhibits proliferation of nasopharyngeal carcinoma (NPC) cells. METHODS: Co-immunoprecipitation (CO-IP) assay, mass spectrometry, Western blotting, immunofluorescence staining, and GST pull-down assay were employed to identify and confirm the protein interacting with VILL that had the highest abundance in NPC cell lines. Transgenic experiments were conducted in both NPC cell lines and nude mice to validate the regulatory role of VILL and its target protein in NPC proliferation. Immunohistochemistry was utilized to assess the correlation of the expression levels of VILL and its target protein in clinical tissue specimens of NPC with the clinical features of the patients. RESULTS: In NPC cell lines (HONE1 EBV and S18), VILL was found to interact most abundantly with the E3 ubiquitin ligase LMO7, and both proteins co-localized in the cytoplasm with direct interactions. Overexpression of LMO7 partially counteracted the inhibitory effect of VILL on NPC cell proliferation. The expression of VILL was significantly downregulated in 136 NPC tissue samples compared to 67 non-cancerous nasopharyngeal tissues (P<0.00001) with close correlation with clinical T stage (P=0.04), N stage (P=0.01), and M stage (P=0.013), whereas LMO7 was highly expressed in all the NPC tissues. CONCLUSIONS VILL overexpression inhibits NPC proliferation probably by suppressing the oncogenic function of LMO7.
Nasopharyngeal Neoplasms/metabolism* ; Humans ; LIM Domain Proteins/metabolism* ; Cell Proliferation ; Cell Line, Tumor ; Animals ; Mice ; Nasopharyngeal Carcinoma ; Mice, Nude ; Transcription Factors/metabolism* ; Carcinoma ; Female ; Microfilament Proteins/genetics* ; Male ; Middle Aged