Renin-angiotensin system activation accelerates atherosclerosis in experimental renal failure by promoting endoplasmic reticulum stress-related inflammation.

In this study, we investigated the association between the renin-angiotensin system (RAS), endoplasmic reticulum (ER) stress and atherosclerosis (AS) in uremic apolipoprotein E knockout (apoE-/-) mice. Mild uremia was induced by a 5/6 nephrectomy (5/6 Nx) in 10-week-old apoE-/- mice. Four weeks after nephrectomy, the mice received losartan or no treatment for 16 weeks. Sham-operated mice served as the controls. We found that uremia accelerated AS at the aortic root. The activation of ER stress and the significant upregulation of pro-inflammatory cytokines and chemokines were observed in the uremic mice. Phosphorylated inositol-requiring 1α (p-IRE1α), an ER stress marker protein, was mainly expressed in macrophages in the atherosclerotic lesions. Treatment with losartan significantly attenuated aortic AS, inhibited ER stress and reduced aortic inflammation. In in vitro experiments, angiotensin II (Ang II) increased the levels of the common ER stress maker, glucose-regulated protein 78 (GRP78) and the phosphorylation of IRE1α in RAW264.7 macrophages. Treatment with losartan inhibited the activation of ER stress and the upregulation of GRP78, and enhanced the expression of nuclear factor-κB (NF-κB) inhibitor (IκB) in Ang II-stimulated RAW264.7 macrophages. IRE1α­siRNA suppressed inflammation and downregulated IκB expression and IκB kinase (IKK) phosphorylation, which inhibited IκB degradation and NF-κB p65 nuclear translocation in Ang II-treated RAW264.7 macrophages. These findings suggest that RAS activation accelerates AS by promoting ER stress-related inflammation in uremic mice.

High glucose induces autophagy of MC3T3-E1 cells via ROS-AKT-mTOR axis.

In the present study, we investigate the function of ROS-AKT-mTOR axis on the apoptosis, proliferation and autophagy of MC3T3-E1 cells, and the proliferation of MC3T3-E1 cells after autophagy inhibition under high glucose conditions. MC3T3-E1 cells cultured in vitro were divided into the following groups: normal control group, N-acetylcysteine (NAC) group, 11.0 mM high glucose group, 11.0 mM high glucose + NAC group, 22.0 mM high glucose group, 22.0 mM high glucose + NAC group, CQ group, 22.0 mM high glucose + CQ group, 3-MA group and 3-MA + 22.0 mM high glucose group. ROS production was measured by DCFH-DA fluorescent probe. Cell proliferation was measured by MTT assay. Cells in different groups were stained with Annexin V-FITC/PI, and then apoptosis rate was detected by flow cytometry. Nucleus morphology was observed under fluorescence microscope after being incubated with Honchest33258. Protein expression was measured using Western blotting and immunofluorescence. Cell apoptosis and proliferation in high glucose group were increased and decreased, respectively, in a dose-dependent manner. Autophagy was significantly induced in high glucose group, even though different concentration of glucose induced autophagy in different stages of autophagy. ROS production in MC3T3-E1 cells was remarkably increased in high glucose group, but not in a dose-dependent manner. NAC, as an antioxidant, reduced ROS production and ameliorated cell apoptosis, proliferation abnormity and autophagy caused by high glucose. Expression of p-AKT and p-mTOR proteins were dramatically decreased in high glucose group, and NAC reversed their expression. In addition, 3-MA, an inhibitor of autophagy, significantly decreased the proliferation of MC3T3-E1 cells. When cocultured with 22.0 mM glucose that induced autophagy, proliferation of MC3T3-E1 cells was not affected compared to 22.0 mM high glucose group. Our present findings reveal that high glucose affects apoptosis, proliferation and autophagy of MC3T3-E1 cells through ROS-AKT-mTOR axis. In addition, autophagy inhibition does not affect the proliferation of MC3T3-E1 cells under high glucose conditions.

MicroRNA­21 inhibits SMAD7 expression through a target sequence in the 3' untranslated region and inhibits proliferation of renal tubular epithelial cells.

MicroRNAs (miRNAs) are a class of small non­coding single­stranded RNAs that regulate gene expression at the posttranscriptional level. Since the identification of miRNA, accumulating research has shown their involvement in numerous biological processes, including timing of developmental patterning, embryogenesis, cell differentiation, organogenesis, growth control and pathogenesis of human diseases. It is estimated that >30% human genes may be regulated by miRNA, and that each miRNA can regulate >100 target mRNAs. The widespread and distinct expression pattern of miRNAs in normal and disease states has been extensively investigated in the context of human diseases. Due to the diversity of targets, it is challenging to identify the specific target genes and elucidate the biological function of a certain miRNAs. In the present study, it was confirmed that SMAD7 is a direct target of miR­21, and overexpression of miR­21 may inhibit the proliferation of rat renal tubular epithelial cells. These findings confirm the results of previous studies, which have demonstrated that miR­21 regulates the expression of SMAD7 protein. However, further investigation is required to determine whether miR­21 is involved in renal development and disease, particularly diabetic nephropathy.

[Silencing hypoxia inducible factor-2α gene by small interference RNA inhibits the growth of mammosphere cells in nude mice under hypoxic microenvironment].

OBJECTIVE: To explore the effects of silencing hypoxia inducible factor-2α (HIF-2α) by small interference RNA on the growth of mammosphere cells in nude mice under hypoxic microenvironment. METHODS: The empty and interference vectors were transfected into MCF-7 cell. Then G418 was added to screen the positive cells to obtain stable cell line. The empty and interference vectors were inoculated subcutaneously into left and right back near hind limb of nude mice. The volume and weight of tumors were calculated respectively. The expressions of HIF-2α, CD44, OCT-4 and KLF-4 protein in xenograft tumor tissues were detected by Western blot. RESULTS: The expression vector of HIF-2α-siRNA was successfully established. The formation of mammosphere was lowered by silencing HIF-2α gene expression. In contract to empty vector group cell, there were obvious decreases in the volumes and weights of tumors in interference group (P < 0.05). The expression of HIF-2α protein of interference group (0.42 ± 0.01) was much lower than that of the empty vector group (0.89 ± 0.03, P < 0.05), the expression of CD44 protein of interference group (0.21 ± 0.01) was much lower than the empty vector group (0.78 ± 0.03, P < 0.05), the expression of OCT-4 protein of interference group (0.42 ± 0.01)was much lower than the empty vector group (0.68 ± 0.03, P < 0.05) and the expression of KLF-4 protein of interference group (0.34 ± 0.01) was much lower than the empty vector group (0.72 ± 0.03, P < 0.05). CONCLUSION: Silencing HIF-2α gene can effectively inhibit the growth of breast cancer stem cells in nude mice under hypoxic microenvironment. Its mechanism may be through inhibited capacity for self-renewal and proliferation of breast cancer stem cells in vivo through the down-regulated expressions of markers associated with stem cells. HIF-2α is expected to become a new target for gene therapy of breast cancer.

Expression of DNMTs and genomic DNA methylation in gastric signet ring cell carcinoma.

The aim of the present study was to investigate the protein expression of DNA methyltransferases (DNMTs) and genomic DNA methylation status of genomes in gastric signet ring cell carcinoma (SRC). Immunohistochemistry was performed to analyze DNMT expression and methylated DNA immunoprecipitation microarray (MeDIP­chip) and MeDIP quantitative real­time PCR (MeDIP­qPCR) were performed to analyze the genomic DNA methylation status in gastric SRC tissue. An increase in DNMT1 and decrease in DNMT3A expression in SRC tissue was observed compared with matched non­cancerous tissue. However, expression of other DNMTs, DNMT2, DNMT3B and DNMT3L, was not found to differ significantly between carcinoma and control. The MeDIP­chip assay revealed that methylation of gene promoters and CpG islands in SRC was higher than those in matched control tissue. However, MeDIP­qPCR analysis demonstrated that specific tumor­related genes, including ABL2, FGF18, TRAF2, EGFL7 and RAB33A were aberrantly hypomethylated in SRC tissue. Results of the current study indicate that gastric SRC may produce complex patterns of aberrant DNA methylation and DNMT expression.

[Expression of breast cancer resistance protein and p-glycoprotein in residual breast cancer tissue after chemotherapy and its correlation with cancer stem cells].

OBJECTIVE: To compare the expression differences of breast cancer resistance protein(BCRP/ABCG2) and P-glycoprotein(P-gp) in breast cancer tissue before chemotherapy and in residual breast cancer tissue, and to explore its correlation with breast cancer stem cells. METHODS: Immunohistochemistry was used to detect the expression of ABCG2, P-gp, and breast cancer stem cells(BCSCs) markers(CD44 and CD24) in breast cancer tissue before chemotherapy and residual breast cancer tissue after chemotherapy. Immunofluorescence was applied for determination of the CD44 and CD24 protein expressions of BCSCs microspheres cells. The monoclone-forming ability of BCSCs microspheres cells was detected by limited dilution assay. The expressions of ABCG2, P-gp, CD44, and CD24 proteins were detected by Western blot. RESULTS: Compared with those in breast cancer tissue before chemotherapy, the expression levels of ABCG2 and P-gp were positively correlated with the expression level of CD44 protein(Χ(2)=41.34, r=0.83;Χ(2)=22.81, r=0.61) in residual breast cancer tissue after chemotherapy;meanwhile, they were negatively correlated with the expression of CD24 protein(Χ(2)=-21.25, r=0.72;Χ(2)=-17.26, r=0.65) (all P<0.05) .The diameter of BCSCs microspheres were increased significantly after chemotherapy.The content of BCSCs increased by about 2.5 times after chemotherapy.The expressions of ABCG2, P-gp and CD44 proteins significantly increased and that of CD24 protein significantly declined(P<0.05) . CONCLUSION: Chemotherapy endows residual breast cancer tissue with cancer stem cells-like features, leading to multidrug resistance of breast cancer.

Expression of DNMTs and MBD2 in GIST.

The aim of this study was to investigate the protein expression of DNA methyltransferases (DNMTs, including DNMT1, DNMT2, DNMT3A, DNMT3B and DNMT3L) and methyl-CpG-binding domain protein 2 (MBD2) in gastrointestinal stromal tumor (GIST). Immunohistochemistry and western blot analysis were used to detect expression of DNMT and MBD2 in 15 pairs of adult GIST and matched non-tumor tissues. The protein expression of DNMT1, DNMT2, DNMT3B, DNMT3L and MBD2 was significantly higher in adult GISTs compared to the matched non-tumor tissues (P<0.05). However, no significant difference was detected in the protein expression of DNMT3A between tumor and non-tumor tissues (P>0.05). Associations between DNMT1 expression and mitotic index, DNMT3B expression and tumor size, as well as DNMT3L expression and Helicobacter pylori infection were detected in GISTs (P<0.05). In conclusion, GISTs exhibit a high protein expression of DNMT (with the exception of DNMT3A) and MBD2.

HMGA2 elicits EMT by activating the Wnt/ß-catenin pathway in gastric cancer.

BACKGROUND: The high mobility group protein A2 (HMGA2) is an architectural transcription factor that plays an important role in the development and progression of many malignant neoplasms. High expression of HMGA2 in gastric cancer correlates with invasiveness of cancer and is an independent prognostic factor. The reason for this might be HMGA2 promoting epithelial-mesenchymal transitions (EMT), which is the key process of metastasis for some underlying mechanisms. AIMS: This study was designed to test whether HMGA2 participates in the EMT and to further understand the underlying mechanisms of EMT promoted by HMGA2. METHODS: We examined the cell biology and molecular biology changes after overexpression and knockdown HMGA2 of gastric cancer cells in vitro and vivo. To further understand the underlying mechanisms of EMT promoted by HMGA2, based on our previous study, we examined the changes of target genes of HMGA2 after overexpression and knockdown HMGA2 of gastric cancer cells. RESULTS: The results indicated that overexpressing HMGA2 enabled enhancing the oncogenic properties of gastric epithelial origin cell in vitro and in vivo. Furthermore, our study showed that HMGA2 was able to elicit EMT and regulate several genes which are closely related to the Wnt/ß-catenin pathway by directly binding to their promoter thereby activating the Wnt/ß-catenin pathway. CONCLUSIONS: The Wnt/ß-catenin pathway activated by HMGA2 might be the underlying mechanism of EMT in gastric cancer cells.

Protective effects of nicotinamide against acetaminophen-induced acute liver injury.

Nicotinamide (NAM), the amide form of vitamin B3, is involved in a wide range of biological processes. Recent evidence revealed the anti-inflammatory and anti-oxidant properties of NAM and suggests it may be used as a novel strategy in the prevention of acute liver injury. In the present study, we investigated the potential protective effects of NAM on acetaminophen (APAP)-induced acute liver injury in mice. Mice were treated with NAM at 400mg/kg 30 min before or after administration of APAP at a hepatotoxic dose of 400mg/kg body weight via intraperitoneal injection. Liver injury and the expression of inflammation-related molecules were determined by histological examination and biochemical analysis, respectively. In addition, the survival rate of mice was assessed after APAP administration. Pretreatment with NAM for 30 min significantly decreased plasma levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and malondialdehyde (MDA), and diminished histopathologic evidence of hepatic toxicity in mice following APAP administration. Similarly, posttreatment with NAM also decreased plasma ALT and AST levels in APAP-administrated mice. Furthermore, both pretreatment and posttreatment with NAM prolonged the survival rate of acute liver injury mice, accompanied by a significant reduction in the plasma levels of pro-inflammatory cytokines tumor necrosis factor-α (TNF-α), interferon-γ (INF-γ), and interleukin-6 (IL-6). Together, these findings suggest that NAM possesses protective effects on APAP-induced liver injury, which may involve the anti-inflammatory action.

Integrin-linked kinase functions as a tumor promoter in bladder transitional cell carcinoma.

The aim of this study was to elucidate the role of the integrin-linked kinase (ILK) gene in development of human bladder transitional cell carcinoma (BTCC). Expression of ILK protein and ILK mRNA in 56 cases of human BTCC tissue and in 30 cases of adjacent normal bladder tissue was detected by immunohistochemistry S-P and reverse transcription polymerase chain reaction (RT-PCR), respectively. Four specific miRNA RNAi vectors targeting human ILK were synthesized and transfected into BIU-87 cells by liposome to obtain stable expression cell strains. The influence of ILK on proliferation of BTCC was detected by MTT, FCM on athymic mouse tumorigenesis. The positive rate of ILK protein in BTCC tissue (53.6%) was much higher than adjacent normal bladder tissue (10.0%) (p<0.05). Similarly, expression of ILK mRNA in BTCC tissue (0.540 ± 0.083) was significantly higher than in adjacent normal bladder tissue (0.492 ± 0.070) (p<0.05). MTT showed that the proliferation ability of miRNA-ILK transfected group was clearly decreased (p<0.05), the cell cycle being arrested in G0/G1-S, an tumorigenesis in vivo was also significantly reduced (p<0.05). ILK gene transcription and protein expression may be involved in the development of BTCC, so that ILK might be the new marker for early diagnosis and the new target for gene treatment.

[Effect of 1,25-dihydroxyvitamin D(3) combined with 5-fluorouracil on IGFBP-3 expression in human esophageal carcinoma 109 cell xenograft in nude mice].

OBJECTIVE: To investigate the effect of 1,25-dihydroxyvitamin D(3) and 5-fluorouracil, either alone or in combination, on the expression of IGFBP-3 in human esophageal carcinoma 109 cell xenograft in nude mice. METHODS: In vitro cultured esophageal carcinoma Eca-109 cells were inoculated subcutaneously in BALB/c mice. The tumor-bearing mice were randomly divided into control group (A), 1,25-dihydroxyvitamin D(3) group (B), 5-fluorouracil group (C), and 1,25-dihydroxyvitamin D(3) plus 5-fluorouracil group (D). 1,25-dihydroxyvitamin D(3) and 5-fluorouracil were administered at the doses of 2.5 ug/kg and 25 mg/kg via intraperitoneal injections, respectively, and the mice in the control group received saline injection only. The tumor growth was observed and the expression of IGFBP-3 in the tumor xenograft was detected using immunohistochemistry. An automatic biochemistry analyzer was used to determine serum calcium levels, and Von Kossa staining was utilized for observation of calcium deposition in the kidneys. RESULTS: Compared with that in group A, the xenograft in groups B, C, and D all showed a lowered growth rate with a smaller tumor volume, and presented with stronger IGFBP-3 positivity and significantly higher levels of IGFBP-3 protein expression (P<0.05). In group D, the protein expression of IGFBP-3 was significantly increased compared with that in groups B and C (P<0.05). Compared with that in group A, serum calcium level was slightly increased in groups B, C, and D, , but no obvious calcium deposition was found in the kidney tissue sections. CONCLUSION: Both 1,25-dihydroxyvitamin D(3) and 5-fluorouracil can inhibit the growth of the tumor xenograft in nude mice, and their combination is more effective. This effect is probably associated with increased protein expression of IGFBP-3 in the xenograft tumor. No calcium deposition occurs in the kidney tissue of the tumor-bearing mice.

Treg/Th17 functional disequilibrium in Chinese uremia on hemodialysis: a link between calcification and cardiovascular disease.

AIM: To investigate the correlation of the functional disequilibrium of regulatory T cells (Treg)/T-helper (Th17) cells with calcification and to explore the significance of their influence on the outcome of cardiovascular disease (CVD) in uremic patients after hemodialysis (HD). METHODS: Out of 66 uremia patients, 36 patients had CVD after HD (maintenance hemodialysis (MHD) group1) and 30 patients did not have CVD (MHD group2). Twenty healthy volunteers were selected as normal control group. Peripheral blood mononuclear cells were isolated and treated with recombinant human bone morphogenetic protein-2 (rhBMP-2). Treg and Th17 frequencies were measured by flow cytometry. Forkhead/winged helix transcription factor (Foxp3) and retinoic acid receptor-related orphan receptor-γt (ROR-γt) mRNA expressions were measured by real-time quantitative polymerase chain reaction. Levels of interleukin (IL)-10 and IL-17 were detected by enzyme-linked immunosorbent assay. RESULTS: When compared with controls, rhBMP-2 upregulates Treg/Th17 functional disequilibrium in uremia patients, displaying higher Treg and Th17 frequencies, Foxp3 and ROR-γt expressions, and levels of cytokines (p < 0.05). These differences were also significant between MHD group1 and group2 (p < 0.05). It was also observed that Treg/Th17 functional disequilibrium was not only correlated with a calcification state but also consistent with the CVD. CONCLUSION: The Treg/Th17 cell function disequilibrium might act synergistically with calcification in the high incidence of CVD after HD.

The C-terminal region of the hepatitis B virus X protein is required for its stimulation of HBV replication in primary mouse hepatocytes.

Hepatitis B virus (HBV) infection is an important risk factor for hepatocellular carcinoma (HCC). The hepatitis B virus X protein (HBx), a multifunctional regulatory protein encoded by HBV, is known to be involved in stimulation of viral replication by modulating cell cycle status. HBx is required for maximal virus replication in plasmid-based replication assays in immortalized human liver HepG2 cells and in primary rat hepatocytes. Moreover, the C-terminal region of HBx is important for HBV replication in HepG2 cells. However, in normal hepatocytes, the region of HBx that is responsible for its effect on cell cycle regulation and HBV replication is unclear. We have demonstrated that HBx is similarly required for maximal HBV replication in primary mouse hepatocytes and that the C-terminus of HBx is essential for its ability to stimulate HBV replication by inducing quiescent hepatocytes to exit G0 phase of the cell cycle but stall in G1 phase. Our studies establish that primary mouse hepatocytes support HBx-dependent HBV replication, and provide further evidence for the effect of the C-terminal region of HBx on HBV infection and replication.

Genome-wide analysis of HMGA2 transcription factor binding sites by ChIP on chip in gastric carcinoma cells.

High mobility group protein A2 (HMGA2) is an architectural transcription factor that plays an important role in development and progression of malignant neoplasias. Recently, some studies reported that HMGA2 is also implicated in epithelial-mesenchymal transitions (EMT) and cancer stem cells. But the underlying mechanisms of these conditions are poorly understood. Therefore, we established an EMT model of gastric carcinoma cells by overexpressing HMGA2 in vitro, then global mapping of HMGA2 potential transcription factor binding sites was identified by promoter microarray in these cells, and the date obtained from the microarrays were validated via chromatin immunoprecipitation-PCR (ChIP-PCR) and real-time PCR. HMGA2 potential target genes were classified in KEGG database and Gene Ontology (GO) analyses. To our knowledge, this is the first report on the genome-wide analysis of HMGA2 downstream direct targets, and these findings will be valuable in understanding the roles of HMGA2 in EMT.

Proinflammatory CD14+CD16+ monocytes are associated with microinflammation in patients with type 2 diabetes mellitus and diabetic nephropathy uremia.

Diabetic nephropathy (DN) is a major cause of type 2 diabetes mellitus (T2DM) mortality. Innate immunity has been shown to be closely associated with the occurrence and progression of T2DM-associated complications. In this study, we investigated the expression of Toll-like receptor 4 (TLR4) and CD14(+)CD16(+) monocytes in patients with T2DM and DN patients with uremia and TLR4 response to lipopolysaccharide (LPS), and to further explore the potential effects of inflammatory immune response in T2DM and DN uremia. Thirty DN patients with uremia, 28 T2DM patients, and 20 healthy volunteers were enrolled for the determination of CD14(+)CD16(+) fluorescence intensity and TLR4 expression on monocytes by using peripheral blood flow cytometry. Serum C-reactive protein (CRP) level was determined by using the immunoturbidimetry. Peripheral blood mononuclear cells (PBMCs) were isolated and stimulated with LPS for 24 h. monocytes were collected to detect NF-κB p65 and phosphorylated STAT5(p-STAT5) expressions by using Western blotting. Supernatants were sampled for the determination of interleukin-6 (IL-6) concentration by using ELISA. Compared to normal control, T2DM patients and DN uremic patients had a significantly higher CD14(+)CD16(+) fluorescence intensity, TLR4 expression, serum IL-6 and CRP level, whilst these biomarkers were more upregulated in DN uremic patients than in T2DM patients. Following the exposure to LPS, PBMCs showed a significant upregulation in NF-κB-p65 and p-STAT5 expression and a remarked increase in Supernatants IL-6 level, in a positive correlation with disease severity. Our results suggest that the disturbance in proinflammatory CD14(+)CD16(+) monocytes occurs in T2DM and DN uremic patients. Such immunological dysfunction may be related to the activation of TLR4/NF-κB and STAT5 signaling pathways underlying the immune abnormalities of CD14(+)CD16(+) monocytes.

[Inhibitory effect of pyrrolidine dithiocarbamate combined with matrine on the growth of human hepatocellular carcinoma xenografts].

OBJECTIVE: To investigate the relationship between activation of nuclear factor-K-gene binding (NF-κB) and apoptosis induced by matrine(MT) in transplanted tumor of human hepatocellular carcinoma in nude mouse. METHODS: Tumors were established by injection of hepatocellular carcinoma cell line HepG2 into the back of nude mice. The mice were divided randomly into four groups: Control group, MT group (35 mg/kg), PDTC group (120 mg/kg) and Combination group: PDTC + MT group (120 mg/kg + 35 mg/kg), the reagents were injected peritoneally. The tumor growth curve of nude mice bearing transplanted tumor were observed and the inhibition ratios were evaluated. Apoptosis of carcinoma cells was analyzed by TUNEL. The DNA-binding activity of NF-κB was determined by electrophoretic mobility shift assay (EMSA). Expression of bcl-2 and bax in carcinoma tissue were detected by immunohistochemical method. NF-κB mRNA, bcl-2 mRNA and bax mRNA in carcinoma tissue were detected by RT-PCR. RESULTS: Pyrrolidine dithiocarbamate (PDTC) could enhance the inhibition of matrine on carcinoma proliferation (P < 0.05). The apoptosis and activation of NF-κB in carcinoma cells could be induced by matrine. PDTC significantly suppressed NF-κB activation induced by matrine in carcinoma cells from 93.64 ± 2.95 to 65.78 ± 5.65 (F = 124.754, P < 0.01). Meanwhile, PDTC increased the apoptosis induced by matrine from 55.9% ± 2.8% to 74.3% ± 4.8% (P < 0.05).A positive correlation observed between the expressions of NF-κB and of bcl-2 (Pearson correlation coefficient = 0.983, P < 0.01). CONCLUSIONS: Matrine could induce apoptosis and activation of NF-κB in transplanted tumor. PDTC could increase apoptosis in hepatocellular carcinoma cells might be due to the suppression of NF-κB activation and the enhancement of bcl-2 expression.

Overexpression of Forkhead Box M1 transcription factor and nuclear factor-κB in laryngeal squamous cell carcinoma: a potential indicator for poor prognosis.

The Forkhead Box M1 transcription factor and nuclear factor-κB have been shown to play important roles in the development and progression of human cancers. However, the functional significance of Forkhead Box M1 transcription factor in laryngeal squamous cell carcinoma and the correlation between Forkhead Box M1 transcription factor and nuclear factor-κB remain unclear. In the current study, we have shown that Forkhead Box M1 transcription factor and nuclear factor-κB were significantly overexpressed in laryngeal squamous cell carcinoma tissues and precancerous lesions, compared with adjacent normal tissues (both P < .001). The overexpression of Forkhead Box M1 transcription factor was significantly associated with histologic differentiation (rs = 0.321, P = .002), T stage (rs = 0.276, P = .009), lymph node metastasis (rs = 0.266, P = .012), and clinical stage (rs = 0.272, P = .010); overexpression of nuclear factor-κB was significantly associated with T stage (rs = 0.404, P < .001), lymph node metastasis (rs = 0.293, P = .005), and clinical stage (rs = 0.425, P < .001). Overexpressions of both Forkhead Box M1 transcription factor and nuclear factor-κB were associated with worse overall survival (P = .041 and P < .001, respectively). Multivariate Cox regression analysis showed that T stage, lymph node metastasis, and nuclear factor-κB were independent prognostic factors for laryngeal squamous cell carcinoma (P = .038, P = .014, and P = .005, respectively). Furthermore, a significant correlation was observed between Forkhead Box M1 transcription factor and nuclear factor-κB (rs = 0.683, P < .001), indicating the potential direct or indirect interaction between them. In conclusion, our results suggest that overexpressions of Forkhead Box M1 transcription factor and nuclear factor-κB and the possible interaction between them may play important roles in the development and progression of laryngeal squamous cell carcinoma, and Forkhead Box M1 transcription factor and nuclear factor-κB may serve as useful prognostic markers for laryngeal squamous cell carcinoma.

[Expression of paxillin in breast cancer cell with high and low metastatic potentiality].

OBJECTIVE: To study the expression of paxillin in the two subgroups of human breast cancer cells with high and low metastatic potentialities and the effect of paxillin on tumor metastasis and adhesion. METHODS: Human breast cancer MDA-MB-435s cells were cultured in Transwell chamber with artificial matrigel, two subgroups of MDA-MB-435s cells with different metastatic potentiality were obtained by the ability of cells penetrating artificial matrigel. The expressions of paxillin mRNA and protein were examined by Immune histochemistry, Western blot and RT-PCR. The adhesion rates of the cells were examined by MTT. RESULTS: It was revealed by Immune histochemistry, Western blot, and RT-PCR that the expressions of paxillin at mRNA and protein levels were significantly higher in the cells with high metastatic potentiality. The difference was significant (t = 25.02,10.10, 17.18, P < 0.01). The adhesion rate was higher in the cells with high metastatic potentiality, and the difference was significant (F = 41.87, P < 0.01). CONCLUSION: The expression of paxillin may play an important role in human breast cancer metastasis and adhesion.

The role of Crk/Dock180/Rac1 pathway in the malignant behavior of human ovarian cancer cell SKOV3.

Small GTPases, particularly the Rho family, are key regulators of cell motility and migration. Dock180 was well known for the main target of signal adaptor protein Crk and acted as a guanine-nucleotide exchange factor for small GTPase Rac1. In the present study, Dock180 was found to combine primarily with CrkI other than CrkII, and its association with Elmo1 was also demonstrated in ovarian cancer cell SKOV3. To evaluate the role of Dock180 in human ovarian cancer cell, we performed RNAi-mediated knockdown of Dock180 in SKOV3 cells using small interfering RNA expression vector. In Dock180 knockdown cells, we found that Elmo1 expression and Rac1 activity were decreased simultaneously. By contrast, the expressions of both another Crk-combining molecule C3G and Rap1 activity were observed to increase obviously. Accordingly, all Dock180 knockdown cells present with evident change in cell morphology, reduced cell proliferation, and attenuated cell migration. Taken together, these results suggest that signal transfer of Crk/Dock180/Rac1 is implicated in actin cytoskeleton reorganization and thus in the cell proliferation, motility, invasion, and of human ovarian cancer cell line SKOV3.

[Effect of P38MAPK signal transduction pathway on apoptosis of THP-1 induced by allicin].

OBJECTIVE: The objective of this paper was to study the change of P38MAPK and Fas in the apoptosis of THP-1 cells induced by allicin. METHOD: The proliferation inhibition rates of THP-1 cells after various treatments were examined by MTT assay. Apoptosis rate was determined with Annexin V- FITC/PI double staining by flow cytometry. The expression and distribution change of the phosphorylation p38MAPK (P-p38MAPK) were detected by immunohistochemical staining. The changes of P-p38 MAPK and Fas proteins were detected by Western blot. RESULT: The proliferations of leukemia cell line THP-1 are inhibited by allicin. MTT assay showed that allicin can inhibit the proliferation of the THP-1 cell, and the inhibition was dependent on both dose and time. The IC50 of 72 hours was 12.8 mg x L(-1). Apoptosis rate detected by Annexin V-FITC/PI was proportional to the concentration of the allicin. After the immunohistochemical staining test, the P-p38MAPK was located in the cell nucleus and plasma, showing deep brown, when adding allicin to THP-1 cell. Western blot test showed that the P-p38MAPK proteins expression was proportional to the concentration of Allicin and was also dose dependent. The levels of P-p38MAPK in negative control group, 1/2 IC50 of 72 hours group and IC50 of 72 hours group were 0.259 8 +/- 0.013 2, 0.61 2 +/- 0.008 3 and 0.505 6 +/- 0.005 5 respectively, and the levels of Fas proteins were 0.287 4 +/- 0.008 9, 0.426 8 +/- 0.007 9 and 0.597 1 +/- 0.010 9 respectively. The difference was statistically significant when compared with the negative control group (P < 0.01). CONCLUSION: Allicin can significantly induce THP-1 cells apoptosis, and its mechanism may be related to the activation of P38MAPK/Fas.