Down-regulation of lncRNA NEAT1 regulated by miR-194-5p/DNMT3A facilitates acute myeloid leukemia.

OBJECTIVE: miR-194-5p and NEAT1 have been reported to be associated with multiple malignancies, but their roles in acute myeloid leukemia (AML) remains not fully understood. METHODS: Bone marrow samples were collected for monocyte separation. qRT-PCR assay was performed to investigate the expression patterns of NEAT1 and miR-194-5p in AML. CCK-8, soft agar colony formation, flow cytometry and transwell assays were employed to explore the biological functions of NEAT1 or miR-194-5p. Methylation PCR was performed to monitor the methylation of NEAT1. Luciferase reporter assay was subjected to verify the relationship between miR-194-5p and DNMT3A. Immunofluorescence and western blotting were performed to detect the alterations of protein expression. RESULTS: NEAT1 and miR-194-5p were both down-regulated in AML. Overexpression of either NEAT1 or miR-194-5p repressed proliferation, induced apoptosis and restrained migration and invasion of AML cells. There was a negative correlation between NEAT1 and DNMT3A in AML. Knockdown of DNMT3A dramatically decreased the methylation of NEAT1. Moreover, DNMT3A was identified as a downstream target of miR-194-5p. Furthermore, down-regulation of DNMT3A rescued the impacts on the malignant phenotypes of NEAT1 inhibition by miR-194-5p inhibitor. CONCLUSION: Altogether, down-regulation of NEAT1 mediated by miR-194-5p/DNMT3A axis promotes AML progression, which might provide therapeutic targets in AML treatment.

Natural Killer Group 2A Expressed on Both Peripheral CD3-CD56+NK Cells and CD3+CD8+T Cells Plays a Pivotal Negative Regulatory Role in the Progression of Hepatitis B Virus-Related Acute-on-Chronic Liver Failure.

To explore the role of surface receptors natural killer group 2A (NKG2A) and natural killer group 2D (NKG2D) on CD3+CD8+T cells and CD3-CD56+NK cells in the progression of hepatitis B virus (HBV)-related acute-on-chronic liver failure (ACLF), we measured the expression of NKG2A and NKG2D on the surface of these 2 types of circulating cells by flow cytometry in 3 groups. One group consists of 36 patients with chronic hepatitis B (CHB), another one consists of 22 patients with HBV-related ACLF, and the last one has 12 normal controls (NC). The experimental result indicated that there was no significant difference in the proportion of CD3+CD8+T cells in total lymphocytes between the 3 groups. However, the percentage of CD3-CD56+NK cells in ACLF group was evidently higher than that in the CHB group (P < 0.05). In addition, the expression of NKG2D on CD3+CD8+T cells in the ACLF group was significantly lower than that in the CHB group (P < 0.05), but there were no statistically significant differences in its percentages on CD3-CD56+NK cells between the 3 groups. The expression of NKG2A on CD3+CD8+T cells in the ACLF group was significantly higher than that in the NC group (P < 0.05), and on NK cells was significantly higher than that in the CHB group (P < 0.05) and NC group (P < 0.01). The increase in ratios of NKG2A to NKG2D on CD3+CD8+T cells and CD3-CD56+NK cells in the ACLF group was significantly more than that in the CHB group and NC group. The results indicate that the imbalance between NKG2A and NKG2D may contribute to the progression of HBV-related ACLF mediated by CD3-CD56+NK cells and CD3+CD8+T cells. Compared with NKG2D, NKG2A expressed on both peripheral CD3-CD56+NK cells and CD3+CD8+T cells plays a more pivotal negative regulatory role in the progression of HBV-related ACLF.

Serum IL-21 levels associated with chronic hepatitis B and hepatitis B-related liver failure.

The aim of the present study was to investigate the role of interleukin (IL)-21 in chronic hepatitis B virus (HBV) infection. IL-21 stimulates T and B cell responses and plays a role in the control of chronic viral infections. Serum IL-21 levels were measured by enzyme immunoassay in 109 patients with chronic HBV infection at various clinical stages, as well as in 19 healthy controls (HCs). The proportion of T cells producing IL-21 in the peripheral blood was assessed by intracellular cytokine staining and flow cytometry. Mean serum IL-21 levels in patients with chronic hepatitis B (CHB) and the HCs were 303.54±152.77 pg/ml and 68.24±9.06 pg/ml, respectively (P=0.003). In addition, the mean serum IL-21 level in patients with hepatitis B-related acute-on-chronic liver failure (HB-ACLF) was 455.38±412.38 pg/ml, which exhibited a statistically significant difference when compared with the HCs (P=0.000). Serum IL-21 levels were highest in the patients with HB-ACLF (455.38±412.38 pg/ml) and exhibited a significant difference when compared with the CHB patients (P=0.04). The mean serum IL-21 levels in patients with cirrhosis also increased, but there was no statistically significant difference when compared with the HCs (P=0.82). The frequency of IL-21+CD4+ cells also increased compared with the HCs and correlated with the number and percentage of lymphocytes in the peripheral blood. Serum IL-21 levels increased in CHB and HB-ACLF patients. Relatively low serum IL-21 levels in CHB may have a causal role in the persistence of HBV infection. Higher serum levels in HB-ACLF may activate T and B cells to eliminate the virus or injure the liver via the release of inflammatory cytokines.

Restoring the Treg cell to Th17 cell ratio may alleviate HBV-related acute-on-chronic liver failure.

AIM: To investigate the role of T helper 17 cells (Th17) and regulatory T cells (Treg) in hepatitis B virus (HBV)-related acute-on-chronic liver failure (ACLF). METHODS: We enrolled 79 patients with HBV infection into the study, 50 patients with HBV-related ACLF and 29 patients with chronic hepatitis B (CHB), from the First Affiliated Hospital of Medical College from January 2009 to June 2012. The ACLF patients were diagnosed according to the criteria recommended by The 19(th) Conference of the Asian Pacific Association for the Study of the Liver in 2009. Twenty healthy individuals with a similar gender and age structures to the two patient groups were also included as the normal controls (NC). Of the 50 ACLF patients, 28 were subsequently classified as non-survivors: 19 patients died from multi-organ failure, 3 underwent liver transplantation, and 6 discontinued therapy during follow-up because of financial reasons. The remaining 22 ACLF patients whose liver and anticoagulation function recovered to nearly normal levels within the next 6 mo were classified as survivors. The number of circulating Treg and Th17 cells was determined upon diagnosis and during the 8th week of follow-up through flow cytometry. RESULTS: The percentage of circulating Treg cells in the ACLF group was significantly higher than that in the CHB group (5.50% ± 1.15% vs 3.30% ± 1.13%, P < 0.01). The percentages of circulating Th17 cells in the ACLF and the CHB groups were significantly higher than that in the NC group (6.32% ± 2.22% vs 1.56% ± 0.44%, P < 0.01; 3.53% ± 1.65% vs 1.56% ± 0.44%, P < 0.01). No significant difference in Treg cell to Th17 cell ratio was observed between the ACLF group and the CHB group (0.98 ± 0.44 vs 1.12 ± 0.64, P = 0.991), whereas those in the two HBV infection groups were significantly lower than that in the NC group (1.85 ± 1.22; both P < 0.01). The percentage of Treg cells in the survivors during the 8(th) week of follow-up was significantly lower than that during peak ACLF severity [total bilirubin (TBIL) peak] (3.45% ± 0.97% vs 5.18% ± 1.02%, P < 0.01). The percentage of Th17 cells in survivors during the 8(th) week of follow-up was significantly lower than that during the peak TBIL (2.89% ± 0.60% vs 5.24% ± 1.46%; P < 0.01). The Treg cell to Th17 cell ratio during the 8(th) week of follow-up was significantly higher than that during the TBIL peak (1.22 ± 0.36 vs 1.10 ± 0.54; P < 0.05). CONCLUSION: Restoring the Treg cell to Th17 cell ratio during the follow-up phase of ACLF could maintain the immune system at a steady state, which favours good prognosis.

[Differential expression of immune-associated genes in two subcloned cell lines from a same human bladder cancer].

AIM: To screen and identify differentially expressed genes in subcloned lines from a same human bladder transitional cell carcinoma (TCC). METHODS: Two bladder TCC cell lines (BLX and BLS-211) with different phenotypes but same origin were used to screen for differentially expressed genes by suppression subtractive hybridization (SSH). RESULTS: 9 over-expressed genes in BLX and 15 in BLS-211 cells were obtained, respectively. Some Bacillus Galmette-Guerin(BCG)- associated genes, such as BCG induced integral membrane protein(BIGM103), fibronectin(FN), complement factor B(BF), were over-expressed in BLX cells. And 8 new ESTs(Expressed Sequence Tag) in BLS-211 cells were collected by GenBank dbEST database with the accession number of DY505708-13, DY230447-8. CONCLUSION: SSH is a powerful method for the identification of differentially expressed genes in different cell lines or clones. Some BCG-associated genes, which are differentially expressed in different cells may contribute to the different response to clinical BCG therapy. The identified new ESTs can be cloned for full length to further study their functions.

Characterization of genes associated with different phenotypes of human bladder cancer cells.

To identify genes associated with morphological phenotypes of human bladder transitional cell carcinoma, we used suppression subtractive hybridization (SSH) to create a subtractive cDNA library of two established cell lines, BLZ-211 and BLS-211, derived from a patient with transitional cell carcinoma of the bladder, then to screen for differentially expressed genes. Real-time reverse transcription-polymerase chain reaction was used to further confirm the selected differentially expressed genes. Forward and reverse subtractive cDNA libraries yielded 168 and 305 putative clones, and among them more than 90% contained the inserts. After differential screening, 36 different transcripts were obtained from 64 cDNA clones of a forward and reverse subtraction library. Among them, 17 were identified as known genes by homology, for example, Vimentin, Keratin7, DDH and UCH-L1. The remaining 19 were unknown expressed genes, and were collected as new expressed sequence tags by the GenBank dbEST database. Their function will be studied further. Thus, SSH appears to be a useful technique for identifying differentially expressed genes between cell lines or clones. Our results, as revealed by SSH, also suggest that differences in gene expression of cytoskeletal proteins might contribute to the different morphologies in BLZ-211 and BLS-211 cells.

[Screening and identification of heterogeneous phenotype-associated genes in human bladder cancer].

OBJECTIVE: To screen and identify heterogeneous phenotype-associated genes of human bladder transitional cell carcinoma. METHODS: Subtractive cDNA libraries was established by means of suppression subtractive hybridization (SSH) on the basis of two human bladder transitional cell carcinoma cell lines (BLZ-211 and BLS-211) derived from the same patient, which had similar changes in chromosomes but different cell phenotypes (in terms of cell shape, susceptibility to 5-Fu and tumorigenic capacity). The positive clones in the library were selected for screening differentially expressed gene fragments by sequence analysis and blasting, and Northern blotting was performed to confirm the differentially expressed genes. RESULTS: The subtractive forward and reverse cDNA libraries consisted of 168 and 206 white clones containing 200-700 bp inserts. After differential screening, 55 cDNA clones containing 35 different transcripts were obtained, among which 15 were identified by homology analysis as known genes (such as those coding for vimentin, keratin 7, dihydrodiol dehydrogenase and thioredoxin reductase), 11 as unknown genes, and 9 as new ESTs (GenBank dbEST database accession number DY505708, DY230447-8, DR008207). CONCLUSION: SSH is a powerful method for identifying differentially expressed genes between different cell lines or clones, and characterization of the identified genes may provide useful information for understanding the genes responsible for different cell phenotypes.

[Liposome-mediated human CD40 gene transfection and human umbilical vein endothelial ECV-304 cells].

OBJECTIVE: To construct an eukaryotic expression vector containing human CD40 gene for its efficient, continuous and stable expression in human umbilical vein endothelial ECV-304 cells. METHODS: The recombinant plasmid pUCD40 was digested with endonucleases to obtain human CD40 gene fragment, which was cloned into pCDNA3.1 vector to construct recombinant eukaryotic expression vector pCDNA3.1(+)/CD40. The recombinant vector was identified by enzyme digestion before introduced into ECV-304 cells via liposome, with the positive cell clones selected with G418. The stable transfection and expression of CD40 in ECV-304 cells were identified by reverse transcription (RT)-PCR, Western blotting and flow cytometry, respectively. RESULTS: Enzyme digestion analysis showed that target gene had been cloned into the recombinant vector. The transfected ECV-304 cells successfully expressed human CD40 as determined by RT-PCR and Western-blotting, and 95% of the cells were CD40-positive as shown by flow cytometry. CONCLUSION: The recombinant eukaryotic expression vector pCDNA3.1(+)/CD40 has been successfully constructed, which is capable of stable transfection and expression of CD40 in ECV-304 cells to facilitate further investigation of the roles of CD40 molecule in antiatherosclerotic drug development.

[Establishment and characterization of a new squamous cell carcinoma cell line CS1213 from the human uterine cervix].

OBJECTIVE: To establish a human cervical carcinoma cell line. METHODS: A primary culture was initiated from malignant tissue collected by dissection of cervical biopsy specimens. Characterizing cells in culture which included morphological observation, biological and karyotypic analysis, experimental tumorigenesis and the expression of p53, bcl-2 and Ki67 genes was carried out. RESULTS: The new established cervical carcinoma cell line (CS1213) had been maintained in culture for over 170 generations. The cells which were nonadherent had a common, rounded appearance with a cell cycle time of 25-hour and a 19 colony formation rate in soft agar. Electron micrographs demonstrated abundant tonofilaments in the cytoplasm. The karyotype showed a hyperdiploid feature with a main chromosome stem number ranged from 80 to 88. The culture was not contaminated by mycoplasma and had a distinct lactic acid dehydrogenase isozyme pattern. High expression level of p53 (31.9%), bcl-2 (89.3%) and Ki67 (33.7%) proteins was detected by flow cytometry. The xenogeneic tumors were grown in nude mice with the histological structure of the original one. CONCLUSIONS: The novel CS1213 cells have the characteristics of human cervical squamous cells and could be used as an appropriate cellular model system for studying tumor invasion and metastasis.