E2F2 is upregulated by the ERK pathway and regulates decidualization via MCM4.

Cell cycle modulation is an important event during decidualization. E2F2 is a transcription regulator that plays a vital role in cell cycle regulation. However, the biological role of E2F2 in decidualization has not yet been identified. In this study, estrogen (E2) and progestin (P4)-induced in vitro and in vivo decidualization models were applied. Our data showed that the expression levels of E2F2 and its downstream target MCM4 were downregulated in the uterus tissues of E2P4-treated mice compared with control mice. In hESCs, exposure to E2P4 resulted in a significant decrease in E2F2 and MCM4 expression. E2P4 treatment reduced hESC proliferation and ectopic expression of E2F2 or MCM4 elevated the viability of E2P4-treated hESCs. In addition, ectopic expression of E2F2 or MCM4 restored the expression of G1 phase-associated proteins. The ERK pathway was inactivated in E2P4-treated hESCs. Treatment with ERK agonist Ro 67-7476 restored the expression of E2F2, MCM4, and G1 phase-associated proteins that were inhibited by E2P4. Moreover, Ro 67-7476 retracted the levels of IGFBP1 and PRL that were induced by E2P4. Collectively, our results indicate that E2F2 is regulated by ERK signaling and contributes to decidualization via regulation of MCM4. Therefore, E2F2/MCM4 cascade may serve as promising targets for alleviating decidualization dysfunction.

Association of rate pressure product trajectories at an early age with left ventricular hypertrophy in midlife: a prospective cohort study.

The joint effect of blood pressure (BP) and heart rate (HR) on cardiovascular disease is unclear. Rate pressure product (RPP), the product of systolic BP and HR, is assessed in this study. This study aimed to determine the longitudinal patterns of RPP from childhood to adulthood and to explore the relationship between RPP trajectories in early life and left ventricular hypertrophy (LVH) in midlife. We included individuals with 3 or more RPP values from 7 visits over a 30-year follow-up period in the Hanzhong Adolescent Hypertension Study cohort to fit trajectory groups and performed logistic regression to evaluate the relative risk of developing LVH. Three discrete trajectories in RPP were identified among 2412 participants assessed from childhood to middle-aged adulthood, which were tagged as "low stable," "moderate stable," and "moderate increasing". A higher waist-to-hip ratio, smoking, alcohol consumption, hypertension, diabetes, and hyperlipidemia were associated with increased RPP trajectories. The Cornell voltage product was positively correlated with RPP in 2017 and was higher in the moderate-stable and moderate-increasing groups than in the low-stable group in RPP trajectories. Compared with the low-stable group, the ORs of LVH were 1.65 (1.13, 2.92) for the moderate-stable and 3.56 (2.26, 5.44) for the moderate-increasing group. Subjects with moderate-stable and moderate-increasing trajectories showed higher probabilities of LVH at an elderly age than those in the low stable trajectory group even after adjusting for multiple cardiovascular risk factors. RPP trajectories are identifiable from childhood and are associated with LVH in midlife. Monitoring RPP trajectories from early life may be an effective approach to predict cardiovascular health status later in life.

ABHD5 inhibits YAP-induced c-Met overexpression and colon cancer cell stemness via suppressing YAP methylation.

Cancer stemness represents a major source of development and progression of colorectal cancer (CRC). c-Met critically contributes to CRC stemness, but how c-Met is activated in CRC remains elusive. We previously identified the lipolytic factor ABHD5 as an important tumour suppressor gene in CRC. Here, we show that loss of ABHD5 promotes c-Met activation to sustain CRC stemness in a non-canonical manner. Mechanistically, we demonstrate that ABHD5 interacts in the cytoplasm with the core subunit of the SET1A methyltransferase complex, DPY30, thereby inhibiting the nuclear translocation of DPY30 and activity of SET1A. In the absence of ABHD5, DPY30 translocates to the nucleus and supports SET1A-mediated methylation of YAP and histone H3, which sequesters YAP in the nucleus and increases chromatin accessibility to synergistically promote YAP-induced transcription of c-Met, thus promoting the stemness of CRC cells. This study reveals a novel role of ABHD5 in regulating histone/non-histone methylation and CRC stemness.

Identification and functional analysis of a core gene module associated with hepatitis C virus-induced human hepatocellular carcinoma progression.

Hepatitis C virus (HCV)-induced human hepatocellular carcinoma (HCC) progression may be due to a complex multi-step processes. The developmental mechanism of these processes is worth investigating for the prevention, diagnosis and therapy of HCC. The aim of the present study was to investigate the molecular mechanism underlying the progression of HCV-induced hepatocarcinogenesis. First, the dynamic gene module, consisting of key genes associated with progression between the normal stage and HCC, was identified using the Weighted Gene Co-expression Network Analysis tool from R language. By defining those genes in the module as seeds, the change of co-expression in differentially expressed gene sets in two consecutive stages of pathological progression was examined. Finally, interaction pairs of HCV viral proteins and their directly targeted proteins in the identified module were extracted from the literature and a comprehensive interaction dataset from yeast two-hybrid experiments. By combining the interactions between HCV and their targets, and protein-protein interactions in the Search Tool for the Retrieval of Interacting Genes database (STRING), the HCV-key genes interaction network was constructed and visualized using Cytoscape software 3.2. As a result, a module containing 44 key genes was identified to be associated with HCC progression, due to the dynamic features and functions of those genes in the module. Several important differentially co-expressed gene pairs were identified between non-HCC and HCC stages. In the key genes, cyclin dependent kinase 1 (CDK1), NDC80, cyclin A2 (CCNA2) and rac GTPase activating protein 1 (RACGAP1) were shown to be targeted by the HCV nonstructural proteins NS5A, NS3 and NS5B, respectively. The four genes perform an intermediary role between the HCV viral proteins and the dysfunctional module in the HCV key genes interaction network. These findings provided valuable information for understanding the mechanism of HCV-induced HCC progression and for seeking drug targets for the therapy and prevention of HCC.

MicroRNA-32 promotes cell proliferation, migration and suppresses apoptosis in breast cancer cells by targeting FBXW7.

BACKGROUND: MicroRNAs are a class of small non-coding RNAs that are involved in many important physiological and pathological processes by regulating gene expression negatively. The purpose of this study was to investigate the effect of miR-32 on cell proliferation, migration and apoptosis and to determine the functional connection between miR-32 and FBXW7 in breast cancer. METHODS: In this study, quantitative RT-PCR was used to evaluate the expression levels of miR-32 in 27 breast cancer tissues, adjacent normal breast tissues and human breast cancer cell lines. The biological functions of miR-32 in MCF-7 breast cancer cells were determined by cell proliferation, apoptosis assays and wound-healing assays. In addition, the regulation of FBXW7 by miR-32 was assessed by qRT-PCR, Western blot and luciferase reporter assays. RESULTS: MiR-32 was frequently overexpressed in breast cancer tissue samples and cell lines as was demonstrated by qRT-PCR. Moreover, the up-regulation of miR-32 suppressed apoptosis and promoted proliferation and migration, whereas down-regulation of miR-32 showed an opposite effect. Dual-luciferase reporter assays showed that miR-32 binds to the 3'-untranslated region of FBXW7, suggesting that FBXW7 is a direct target of miR-32. Western blot analysis showed that over-expression of miR-32 reduced FBXW7 protein level. Furthermore, an inverse correlation was found between the expressions of miR-32 and FBXW7 mRNA levels in breast cancer tissues. Knockdown of FBXW7 promoted proliferation and motility and suppressed apoptosis in MCF-7 cells. CONCLUSIONS: Taken together, the present study suggests that miR-32 promotes proliferation and motility and suppresses apoptosis of breast cancer cells through targeting FBXW7.

Integrated analysis of differentially expressed genes and pathways in triple­negative breast cancer.

Triple­negative breast cancer (TNBC) is a heterogeneous disease characterized by an aggressive phenotype and reduced survival. The aim of the present study was to investigate the molecular mechanisms involved in the carcinogenesis of TNBC and to identify novel target molecules for therapy. The differentially expressed genes (DEGs) in TNBC and normal adjacent tissue were assessed by analyzing the GSE41970 microarray data using Qlucore Omics Explorer, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes. Pathway enrichment analyses for DEGs were performed using the Database for Annotation, Visualization and Integrated Discovery online resource. A protein­protein interaction (PPI) network was constructed using Search Tool for the Retrieval of Interacting Genes, and subnetworks were analyzed by ClusterONE. The PPI network and subnetworks were visualized using Cytoscape software. A total of 121 DEGs were obtained, of which 101 were upregulated and 20 were downregulated. The upregulated DEGs were significantly enriched in 14 pathways and 83 GO biological processes, while the downregulated DEGs were significantly enriched in 18 GO biological processes. The PPI network with 118 nodes and 1,264 edges was constructed and three subnetworks were extracted from the entire network. The significant hub DEGs with high degrees were identified, including TP53, glyceraldehyde­3­phosphate dehydrogenase, cyclin D1, HRAS and proliferating cell nuclear antigen, which were predominantly enriched in the cell cycle pathway and pathways in cancer. A number of critical genes and pathways were revealed to be associated with TNBC. The present study may provide an improved understanding of the pathogenesis of TNBC and contribute to the development of therapeutic targets for TNBC.

miRNA143 Induces K562 Cell Apoptosis Through Downregulating BCR-ABL.

BACKGROUND Leukemia seriously threats human health and life. MicroRNA regulates cell growth, proliferation, apoptosis, and cell cycle. Whether microRNA could be treated as a target for leukemia is still unclear and the mechanism by which microRNA143 regulates K562 cells needs further investigation. MATERIAL AND METHODS miRNA143 and its scramble miRNA were synthesized and transfected to K562 cells. MTT assay was used to detect K562 cell proliferation. Flow cytometry and a caspase-3 activity detection kit were used to test K562 cell apoptosis. Western blot analysis was performed to determine breakpoint cluster region-Abelson (BCR-ABL) expression. BCR-ABL overexpression and siRNA were used to change BCR-ABL level, and cell apoptosis was detected again after lipofection transfection. RESULTS miRNA143 transfection inhibited K562 cell growth and induced its apoptosis. miRNA143 transfection decreased BCR-ABL expression. BCR-ABL overexpression suppressed miRNA143-induced K562 cell apoptosis, while its reduction enhanced miRNA143-induced apoptosis. CONCLUSIONS miRNA143 induced K562 cell apoptosis through downregulating BCR-ABL. miRNA143 might be a target for a new leukemia therapy.

Decreased expression of Sushi Domain Containing 2 correlates to progressive features in patients with hepatocellular carcinoma.

BACKGROUND: Sushi Domain Containing 2 (SUSD2) has been identified as a regulator of colon and breast cancer. Increasing evidence suggests that SUSD2 plays a key role in tumorigenesis. However, the SUSD2 expression status and its functions in hepatocellular carcinoma (HCC) are still unrevealed. In the present study, we intended to investigate SUSD2 expression status and its correlation with the clinicopathological features in HCC patients. Furthermore,we examined the influence of SUSD2 on the proliferation, apoptosis, invasion and migration of the HCC cell lines HepG2 and SMMC7721. METHODS: We evaluated the SUSD2 expression in HCC tissues and paired normal liver tissues by quantitative real-time PCR and western blotting analysis. The clinicopathological significance of SUSD2 was investigated by immunohistochemistry (IHC) on a HCC tissue microarray. Receiver operating characteristic (ROC) analysis was applied to determine the optimal cut-off score for positive expression of SUSD2. The correlation between SUSD2 protein expression and clinicopathological features of HCC was analyzed by Chi square test. The cell proliferation, apoptosis, invasion and migration potential were observed to detect the functions of SUSD2 in HCC cells. RESULTS: Decreased expression of SUSD2 mRNA and protein were observed in the majority of HCC tissues, compared with paired normal liver tissues. When SUSD2 high expression percentage was determined to be above 52.5 % (area under ROC curve = 0.769, P = 0.000), low expression of SUSD2 was observed in 62.2 % (112/180) of HCC tissues and high expression of SUSD2 was observed in all normal liver tissues (16/16) by IHC. Decreased expression of SUSD2 in patients was correlated with high histological grade (χ(2) = 5.198, P = 0.023), advanced clinical stage (χ(2) = 30.244, P = 0.000), pT status (χ(2) = 33.175, P = 0.000), pN status (χ(2) = 4.785, P = 0.029), pM status (χ(2) = 4.620, P = 0.032). Down-regulation of SUSD2 promoted cell proliferation,invasion and migration,reduced the cell apoptosis. CONCLUSIONS: Our findings suggest that SUSD2 may play as a tumor suppressor in HCC cells and could be served as an additional potential marker for diagnosis.

Reduced expression of sushi domain containing 2 is associated with progression of non-small cell lung cancer.

Sushi domain containing 2 (SUSD2) has been identified as a gene encoding an 822-amino acid protein, which contains a transmembrane domain and functional domains inherent to adhesion molecules. Previous studies have reported that increased expression of SUSD2 has a critical role in tumorigenesis in human breast cancer. However, to the best of our knowledge, SUSD2 expression status and its correlation with the clinicopathological features of non-small cell lung cancer (NSCLC) have not previously been investigated. In the present study, reverse transcription-quantitative polymerase chain reaction and western blotting were used to evaluate SUSD2 messenger RNA (mRNA) and protein expression in NSCLC and adjacent normal lung tissues. The clinicopathological significance of SUSD2 was investigated by immunohistochemical analysis of an NSCLC tissue microarray. Receiver operating characteristic analysis was used to determine the cut-off score for positive expression of SUSD2. Furthermore, the correlation between SUSD2 expression and the clinicopathological features of NSCLC was analyzed by χ2 test. The results revealed that SUSD2 mRNA (P<0.0001) and protein (P<0.0001) expression levels were significantly decreased in NSCLC tissues compared with those of adjacent normal tissues. When the SUSD2 positive expression percentage was determined to be >47.5% (area under ROC curve, 0.799; P<0.000), positive expression of SUSD2 was observed in 100% (32/32) of normal lung tissues and 55% (88/160) of NSCLC tissues by immunohistochemistry (χ2=21.160; P<0.000). Furthermore, it was demonstrated that the reduced SUSD2 protein levels in cancer tissues were positively correlated with poor histological grade (χ2=41.764; P<0.000), advanced clinical stage (χ2=10.790; P=0.013), higher pT (χ2=9.070; P=0.028) and positive regional lymph node metastasis (χ2=15.399; P=0.002). In conclusion, these data suggest that the reduced expression of SUSD2 is associated with the progression of NSCLC and may have a role in the pathogenesis of NSCLC.

[Expression of E3 ligase HERC4 in breast cancer and its clinical implications].

OBJECTIVE: To investigate the expression of HERC4 in human breast cancer tissues and its relationship with the clinicopathological features. METHODS: RT-qPCR was used to detect mRNA expression of HERC4, and Western blotting and immunohistochemistry were employed to detect protein expression of HERC4 in 67 breast cancer tissues and adjacent breast tissues. RESULTS: The results of RT-qPCR showed a significantly higher mRNA expression of HERC4 in breast cancer tissues than in the adjacent breast tissues (P<0.05). Western blotting demonstrated HERC4 over-expression in breast cancer tissues compared with the adjacent breast tissues (P<0.05). Immunohistochemistry revealed HERC4 expression located predominantly in the cell cytoplasm. Positive HERC4 expression was detected in 61.2% of the breast cancer tissues as compared to 19.4% in the adjacent breast tissues, and its expression level was closely correlated with TNM stage and the histological grade (P<0.05). CONCLUSION: HERC4 is correlated with the tumorigenesis and progression of breast cancer and may serve as a potential biomarker for early diagnosis and also as a potential therapeutic target in breast cancer.

Imaging of T-cell receptor fused to CD3ζ reveals enhanced expression and improved pairing in living cells.

T cell receptor (TCR) gene adoptive therapy is a promising clinical approach for the treatment of malignant tumors and viral diseases. However, the effectiveness of this strategy is hampered by the generation of mixed TCR heterodimers comprising both exogenous and endogenous TCR chains (i.e., mispairing of TCR chains). In the present study, we constructed genetically encoded reporters fused to a pair of fluorescent proteins [enhanced cyan fluorescent protein (ECFP)/enhanced yellow fluorescent protein (EYFP)] to monitor the expression of TCRαζßζ and pairing between TCRαζ and TCRßζ. We demonstrate that these reporters provide accurate images of TCRαζßζ expression, which is markedly stronger with evident microclusters accumulated at the plasma membrane compared to wild-type (wt)TCR. Using fluorescence resonance energy transfer (FRET) analysis, we demonstrate that, in addition to the improved pairing, the expression and assembly of TCRαζßζ are independent of endogenous CD3 subunits. These results suggest that the fusion genes, TCRαζ and TCRßζ, coupled to ECFP and EYFP, respectively can effectively monitor the expression and interaction in cells. Our data suggest a novel strategy with which it is possible to effectively express and pair TCRαζßζ, thus making TCR gene adoptive therapy more effective.

The role of PinX1 in growth control of breast cancer cells and its potential molecular mechanism by mRNA and lncRNA expression profiles screening.

As a major tumor suppressor gene, the role of PinX1 in breast cancer and its molecular mechanism remain unclear. In this study, overexpression of PinX1 was generated in 3 breast cancer cell lines, and knockdown of PinX1 was performed in a nontumorigenic breast cell line. The regulation of PinX1 on cell proliferation and cell cycle was observed. A microarray-based lncRNA and mRNA expression profile screening was also performed. We found a lower growth rate, G0/G1 phase arrest, and S phase inhibition in the PinX1 overexpressed breast cancer cells, while a higher growth rate, decreased G0/G1 phase, and increased S phase rate in the PinX1 knocked-down nontumorigenic breast cell. A total of 977 mRNAs and 631 lncRNAs were identified as differentially expressed transcripts between PinX1 overexpressed and control MCF-7 cells. Further analysis identified the involvement of these mRNAs in 52 cancer related pathways and various other biological processes. 11 enhancer-like lncRNAs and 25 lincRNAs with their adjacent mRNA pairs were identified as coregulated transcripts. Our results confirmed the role of PinX1 as a major tumor suppressor gene in breast cancer cell lines and provided information for further research on the molecular mechanisms of PinX1 in tumorigenesis.

Knockdown of CD44 enhances chemosensitivity of acute myeloid leukemia cells to ADM and Ara-C.

It is known that chemoresistance is a major cause of treatment failure in acute myeloid leukemia (AML). Substantial data indicate that the CD44 adhesion molecule is strongly expressed on AML blasts and that it can also inhibit apoptosis. Our study shows that drug resistance of the AML cell line HL60/ADM is due to overexpression of CD44. In an in vitro study, we knocked down CD44 in the HL60/ADM cell line using small interfering RNA (siRNA). Cell proliferation and the 50% inhibitory concentrations (IC50) were determined by Cell Counting Kit-8 (CCK-8) assay. Cell apoptosis and intracellular ADM accumulation were detected by flow cytometry. Expression of CD44, Bcl-2, c-Myc were assayed by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot. The results indicate that the expression of CD44 in HL60/ADM cell line was much higher than in HL60 cell, and siRNA targeted CD44 (siRNA/CD44) could silence its expression in both mRNA and protein levels effectively. siRNA/CD44 substantially induces cell apoptosis, inhibits cell proliferation, enhances susceptibility to ADM and Ara-C, and at the same time increases intracellular ADM accumulation even reverses chemoresistance to ADM and Ara-C. Furthermore, by qRT-PCR and Western blot, we found that siRNA/CD44 decreases Bcl-2 and c-Myc synthesis. Our study provides a novel clue that CD44 plays a significant role in the chemoresistance of AML cells to Ara-C and ADM. Moreover, this provides a new direction to the approaches that combination therapy including targeting CD44 may overcome drug resistance and improve treatment effects.

Assay of OAZ1 mRNA levels in chronic myeloid leukemia combined with application of leukemia PCR array identified relevant gene changes affected by antizyme.

Ornithine decarboxylase antizyme (OAZ) has recently emerged as a potential therapeutic target in various malignant tumors because it plays vital roles in cellular functions including proliferation, differentiation, apoptosis and genomic stability. Therefore, there is a significant interest in discovering its function in chronic myeloid leukemia (CML). Firstly, OAZ1 mRNA was measured by qRT-PCR in 43 cases with CML and 23 controls, and we demonstrated that it is significantly down-regulated in CML patients. To further understand its functions in CML pathogenesis, OAZ1 was overexpressed, and the human leukemia PCR array analysis was used to monitor the expression of key genes commonly involved in leukemia development, classification and therapeutic response. We found several favorable up-regulation factors including CXCL10, DAPK1 and IKZF3. In conclusion, OAZ1 may be a useful therapeutic target in CML due to its potential ability to induce erythroid differentiation and cell apoptosis. These functions were proven to be associated with several gene changes that were directly or indirectly caused by OAZ1. The mechanism of how OAZ1 affects other genes remains to be elucidated.

The expression and clinical significance of HERC4 in breast cancer.

BACKGROUND: Increasing evidence suggest that ubiquitin-proteasome system (UPS) plays a key role in tumorigenesis. HERC4 is a recently identified ubiqutin ligase. However, the expression status and biological functions of HERC4 in cancers are not clearly. METHODS: We evaluated the HERC4 expression in breast cancer cell lines and breast tumor tissues by quantitative real-time PCR and western blot analysis. To investigate the clinicopathological significance of HERC4, immunohistochemistry analysis for HERC4 was performed on a tissue microarray including 13 benign fibroadenoma, 15 intraductal carcinoma, 120 histologically confirmed invasive ductal carcinoma. Receiver operating characteristic (ROC) analysis was applied to determine the optimal cut-off score for positive expression of HERC4, when HERC4 positive expression percentage was above 60%, tumor was defined as "positive". RESULTS: HERC4 was up-regulated in breast cancer cell lines and breast tumor tissues compared to non-tumorigenic cell line and adjacent normal breast tissues. According to ROC analysis, HERC4 positive expression was detected in 1/16 (6.3%) of normal breast tissue, in 3/13 (23.1%) of fibroadenoma, in 6/15 (40%) of intraductal carcinoma and 66/120 (55%) of invasive ductal carcinoma. Positive expression of HERC4 was positively correlated with pT status, pN status, clinical stage and histological grade of patients with invasive ductal carcinoma (p < 0.05). CONCLUSIONS: Our findings suggest that HERC4 was a significant diagnostic marker for invasive ductal carcinoma of the breast.

Extract of Perilla frutescens inhibits tumor proliferation of HCC via PI3K/AKT signal pathway.

In this study, isoegomaketone(IK) was isolated from Perilla frutescens(L.), a Chinese herbal. The effects of IK were examined by cell viability assay, colony formation assay, xenograft tumor assay and western blotting in HCC cells. We found that IK inhibited cell viability, and its administration decreased tumor volume and weight profoundly. The presence of IK(10 nmol/l) produced a dramatic decrease of pAkt, while total Akt level was not affected. The data suggested that IK from perilla suppressed HCC tumor growth via blocking PI3K/Akt signaling pathway.

[Construction and identification of the eukaryotic expression vector expressing short hairpin RNA targeting human COL1A1].

OBJECTIVE: To construct the eukaryotic expression vector of short hairpin RNA (shRNA) targeting human collagen type 1 alpha 1 (COL1A1) and observe its inhibiting effect on the expression of target gene. METHODS: The complementary oligonucleotide sequences coding shRNA were designed and synthesized according to the sequence of human COL1A1 gene, and cloned into the linearized pSilencer(TM);2.1-U6 neo vector. The recombinant vector was confirmed by enzyme digestion analysis and DNA sequencing, and then the positive clones were transfected to human breast cancer cell MDA-MB-231 by Lipofectamine(TM);2000. The stable cell line was selected by G418. The expression of COL1A1 gene was detected by semi-quantitative RT-PCR and Western blot analysis. RESULTS: Double-enzyme digestion and DNA sequencing verified the correct sequences of the recombinant plasmid pshRNA-COL1A1. Compared with the control group, the expression level of COL1A1 mRNA and protein was inhibited markedly by pshRNA-COL1A1-1 or pshRNA-COL1A1-2 transfection, and the inhibitory rates were respectively (44.41±3.90)%, (63.05±3.13)% in RT-PCR and (45.50±2.71)%, (66.98±2.08)% in Western blot analysis. CONCLUSION: Specific shRNA interference plasmid vector targeting COL1A1 gene mRNA was constructed successfully.

Associations between the four toll-like receptor polymorphisms and the risk of gastric cancer: a meta-analysis.

PURPOSE: The association between Toll-like receptor 2 (TLR2) -196 to -174del polymorphism and Toll-like receptor 4 (TLR4) polymorphisms (Asp299Gly, Thr399Ile, and 3725G>C) and gastric cancer risk are still conflicting. For better understanding of the effects of these four polymorphisms on gastric cancer risk, a meta-analysis was performed. METHODS: An extensive search was performed to identify all case-control studies investigating such associations. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated to assess the relationship. RESULTS: A total of 21 studies (3,436 cases and 4,239 controls) were found to be eligible for meta-analysis. In the overall analysis, a significantly increased risk was observed in TLR4 Asp299Gly polymorphism (G allele vs. A allele: OR=1.84, 95%CI: 1.41, 2.39; GA vs. AA: OR=1.89, 95%CI: 1.43, 2.48; Recessive model: OR=1.90, 95%CI: 1.44, 2.49) and TLR4 Thr399Ile polymorphism (T allele vs. C allele: OR=1.97, 95%CI: 1.22, 3.18; TC vs. CC: OR=1.94, 95%CI: 1.19, 3.15; Recessive model: OR=1.98, 95%CI: 1.21, 3.21), whereas no associations were found in any genetic models of TLR2 -196 to -174del and TLR4 3725G>C polymorphisms. Similar results were found in the subgroup analyses by ethnicity. However, we detected that A allele carriers of the TLR4 Asp299Gly polymorphism might have an increase risk of gastric cancer in the Helicobacter pylori-positive population (G allele vs. A allele: OR=2.01, 95%CI: 1.22, 3.31). CONCLUSION: The results of this meta-analysis indicate that the TLR4 Asp299Gly and Thr399Ile polymorphisms are risk factors for gastric cancer development.

Low expression of miR-196b enhances the expression of BCR-ABL1 and HOXA9 oncogenes in chronic myeloid leukemogenesis.

MicroRNAs (miRNAs) can function as tumor suppressors or oncogene promoters during tumor development. In this study, low levels of expression of miR-196b were detected in patients with chronic myeloid leukemia. Bisulfite genomic sequencing PCR and methylation-specific PCR were used to examine the methylation status of the CpG islands in the miR-196b promoter in K562 cells, patients with leukemia and healthy individuals. The CpG islands showed more methylation in patients with chronic myeloid leukemia compared with healthy individuals (P<0.05), which indicated that low expression of miR-196b may be associated with an increase in the methylation of CpG islands. The dual-luciferase reporter assay system demonstrated that BCR-ABL1 and HOXA9 are the target genes of miR-196b, which was consistent with predictions from bioinformatics software analyses. Further examination of cell function indicated that miR-196b acts to reduce BCR-ABL1 and HOXA9 protein levels, decrease cell proliferation rate and retard the cell cycle. A low level of expression of miR-196b can cause up-regulation of BCR-ABL1 and HOXA9 expression, which leads to the development of chronic myeloid leukemia. MiR-196b may represent an effective target for chronic myeloid leukemia therapy.