Hypoxia-inducible factor 2α is a novel inhibitor of chondrocyte maturation.

Hypoxic environment is essential for chondrocyte maturation and longitudinal bone growth. Although hypoxia-inducible factor 1 alpha (Hif-1α) has been known as a key player for chondrocyte survival and function, the function of Hif-2α in cartilage is mechanistically and clinically relevant but remains unknown. Here we demonstrated that Hif-2α was a novel inhibitor of chondrocyte maturation through downregulation of Runx2 stability. Mechanistically, Hif-2α binding to Runx2 inhibited chondrocyte maturation by Runx2 degradation through disrupting Runx2/Cbfß complex formation. The Hif-2α-mediated-Runx2 degradation could be rescued by Cbfß transfection due to the increase of Runx2/Cbfß complex formation. Consistently, mesenchymal cells derived from Hif-2α heterozygous mice were more rapidly differentiated into hypertrophic chondrocytes than those of wild-type mice in a micromass culture system. Collectively, these findings demonstrate that Hif-2α is a novel inhibitor for chondrocyte maturation by disrupting Runx2/Cbfß complex formation and consequential regulatory activity.

Prognostic implications of ezrin and phosphorylated ezrin expression in non-small cell lung cancer.

BACKGROUND: The cytoskeletal organizer ezrin is a member of the ezrin-radixin-moesin (ERM) family and plays important roles in not only cell motility, cell adhesion, and apoptosis, but also in various cell signaling pathways. Phosphorylation at Thr-567 and Tyr-353 are key regulatory events in the transition of the dormant to active form of ezrin. This study investigated the prognostic implications of ezrin and phosphorylated ezrin (p-ezrin) expression in non-small cell lung carcinoma (NSCLC). METHODS: Ezrin and p-ezrin protein expressions were examined by immunohistochemistry in 150 NSCLC and adjacent non-tumor tissues and 14 normal lung tissues. qRT-PCR was used to determine ezrin mRNA expression levels in fresh tissues. The correlations between overexpression of ezrin and p-ezrin and the clinicopathological features of NSCLC were analyzed. The survival rates were calculated by the Kaplan-Meier method for 108 NSCLC cases. RESULTS: Ezrin and ezrinThr-567 proteins showed cytosolic and membranous staining patterns; however, ezrinTyr-353 protein only showed cytosolic staining. Ezrin and p-ezrin were significantly upregulated in NSCLC compared with the normal counterparts. Increased ezrin, ezrinThr-567, and ezrinTyr-353 levels were correlated with the late stage and poor differentiation of NSCLC. However, only ezrinThr-567 was correlated with the presence of lymph node metastasis. In regard to survival, only ezrinThr-567 was related with the overall survival time of patients with NSCLC, and both ezrin and ezrinThr-567 were associated with shortened survival time for patients with early stage NSCLC. CONCLUSIONS: Ezrin and p-ezrin, especially ezrinThr-567, may prove to be useful as a novel prognostic biomarker of NSCLC.

The effects of resveratrol in animal models of primary osteoporosis: a systematic review and meta-analysis.

BACKGROUND: There is still a lack of sufficient evidence-based medical data on the effect of resveratrol (Res) on primary osteoporosis (OP). This meta-analysis aimed to comprehensively evaluate the role of Res in animal models of primary OP. METHODS: The PubMed, Cochrane Library, Web of Science and Embase databases were searched up to August 2023. The risk of bias was assessed by the SYRCLE RoB tool. Random- or fixed-effects models were used to determine the 90% confidence interval (CI) or standardized mean difference (SMD). Statistical analysis was performed with RevMan 5.4 and Stata 14.0. RESULTS: A total of 24 studies containing 714 individuals were included. Compared with those in the control group, the bone mineral density (BMD) (P < 0.00001), bone volume/total volume (BV/TV) (P < 0.001), trabecular thickness (Tb.Th) (P < 0.00001), and trabecular number (Tb.N) (P < 0.00001) were markedly greater, and the trabecular separation (Tb.Sp) (P < 0.00001) was significantly greater. Compared with the control group, the Res group also exhibited marked decreases in alkaline phosphatase (ALP) (P < 0.05), tartrate-resistant acid phosphatase 5b (TRAP5b) (P < 0.01), and type I collagen strong carboxyl peptide (CTX-1) (P < 0.00001) and a marked increase in osteoprotegerin (OPG) (P < 0.00001). CONCLUSION: In summary, we concluded that Res can markedly increase BMD, improve morphometric indices of trabecular microstructure and serum bone turnover markers (BTMs), and exert a protective effect in animal models of primary osteoporosis. This study can supply experimental reference for Res in primary osteoporosis treatment.

Serum amyloid A expression in liver promotes synovial macrophage activation and chronic arthritis via NFAT5.

Nuclear factor of activated T-cells 5 (NFAT5), an osmo-sensitive transcription factor, can be activated by isotonic stimuli, such as infection. It remains unclear, however, whether NFAT5 is required for damage-associated molecular pattern-triggered (DAMP-triggered) inflammation and immunity. Here, we found that several DAMPs increased NFAT5 expression in macrophages. In particular, serum amyloid A (SAA), primarily generated by the liver, substantially upregulated NFAT5 expression and activity through TLR2/4-JNK signalling pathway. Moreover, the SAA-TLR2/4-NFAT5 axis promoted migration and chemotaxis of macrophages in an IL-6- and chemokine ligand 2-dependent (CCL2-dependent) manner in vitro. Intraarticular injection of SAA markedly accelerated macrophage infiltration and arthritis progression in mice. By contrast, genetic ablation of NFAT5 or TLR2/4 rescued the pathology induced by SAA, confirming the SAA-TLR2/4-NFAT5 axis in vivo. Myeloid-specific depletion of NFAT5 also attenuated SAA-accelerated arthritis. Of note, inflammatory arthritis in mice strikingly induced SAA overexpression in the liver. Conversely, forced overexpression of the SAA gene in the liver accelerated joint damage, indicating that the liver contributes to bolstering chronic inflammation at remote sites by secreting SAA. Collectively, this study underscores the importance of the SAA-TLR2/4-NFAT5 axis in innate immunity, suggesting that acute phase reactant SAA mediates mutual interactions between liver and joints and ultimately aggravates chronic arthritis by enhancing macrophage activation.

Efficacy and safety of sacubitril/valsartan in the treatment of middle-aged and elderly patients with hypertension: a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: With the increase of hypertensive patients worldwide, the need for better antihypertensive drugs to achieve blood pressure standards and reduce complications is of great clinical significance. As an angiotensin receptor-neprilysin inhibitor, sacubitril/valsartan has been widely used in the treatment of heart failure, but its efficacy and safety in the treatment of middle-aged and elderly hypertensive patients are still controversial. Therefore, we performed a meta-analysis to compare the efficacy and safety of sacubitril/valsartan and other antihypertensive drugs in the treatment of middle-aged and elderly patients with hypertension. METHODS: The databases of PubMed, Embase, and Web of Science were systematically searched from their establishment to February 2022 to collect the randomized controlled trials (RCTs) of sacubitril/valsartan and other antihypertensive drugs in the treatment of middle-aged and elderly hypertensive patients. The Cochrane Collaboration's tool was used to assess risk of bias for included studies, and the meta-analysis was performed by using RevMan 5.3. RESULTS: In all, 7 studies which met the criteria were included, with a total sample size of 3,323 patients, including 1,899 patients treated with sacubitril/valsartan, and 1,424 patients treated with angiotensin II receptor blockers (ARBs). The meta-analysis showed that compared with other antihypertensive drugs, sacubitril/valsartan can significantly reduce mean reductions in sitting systolic blood pressure [mean difference (MD) =-4.70, 95% confidence interval (CI): -5.79 to -3.61, P<0.001], mean reductions in sitting diastolic blood pressure (MD =-2.29, 95% CI: -2.53 to -2.04, P<0.001), 24-hour mean reductions in ambulatory systolic blood pressure (MD =-3.36, 95% CI: -4.08 to -2.64, P<0.001), and 24-hour mean reductions in ambulatory diastolic blood pressure (MD =-1.49, 95% CI: -1.99 to -0.99, P<0.001), while there was no significant difference in the incidence of adverse events [odds ratio (OR) =1.14, 95% CI: 1.00 to 1.31, P=0.06], serious adverse events (OR =1.06, 95% CI: 0.64 to 1.76, P=0.81), and discontinuations due to adverse events (OR =0.86, 95% CI: 0.51 to 1.46, P=0.58). DISCUSSION: Compared with other antihypertensive drugs, sacubitril/valsartan may be more effective in lowering blood pressure, and its safety may be comparable to that of ARBs. However, these results have to be confirmed by future RCTs with larger sample sizes and higher quality, and the long-term benefits of sacubitril/valsartan require further observation.

Baicalein Induces Apoptosis of Rheumatoid Arthritis Synovial Fibroblasts through Inactivation of the PI3K/Akt/mTOR Pathway.

Purpose: Rheumatoid arthritis (RA) shows abnormal proliferation, apoptosis, and invasion in fibroblast-like synoviocytes (FLSs). Baicalein (BAI), extracted from Scutellaria baicalensis, is used as an anticancer drug through inducing cancer cells apoptosis. However, the mechanism of BAI in RA progression still remains unknown. Here, we demonstrated that BAI inhibited FLS proliferation and migration, whereas it enhanced apoptosis via the PI3K/Akt/mTOR pathway in vitro. Methods: Cell viability and colony formation were analyzed by MTT and plate colony formation assays in SW982 cells, respectively. Apoptosis was detected by flow cytometry and western blotting. Epithelial-mesenchymal transition (EMT), MMP family proteins (MMP2/9), and the PI3K/Akt/mTOR pathway were detected by western blot. Cell migration was detected by scratch healing assay under BAI treatment in SW982 cells. Results: BAI dose-dependently inhibited cell viability and colony forming in SW982 cells. BAI upregulated apoptotic proteins and downregulated EMT-related proteins, resulting in enhanced cell apoptosis and inhibited cell migration in SW982 cells. BAI also dose-dependently inhibited the phosphorylation of PI3K, Akt, and mTOR. Conclusions: These results indicated that BAI inhibited FLSs proliferation and EMT, whereas induced cell apoptosis through blocking the PI3K/Akt/mTOR pathway, supporting clinical application for RA progression.

The molecular mechanism of baicalein repressing progression of gastric cancer mediating miR-7/FAK/AKT signaling pathway.

BACKGROUND: Baicalein (BAI) has a significant anti-cancerous function in the treatment of gastric cancer (GC). Focal adhesion kinase (FAK) is a key regulatory molecule in integrin and growth factor receptor mediated signaling. MicroRNA-7 (miR-7), has been considered as a potential tumor suppressor in a variety of cancers. However, the possible mechanisms by which BAI inhibiting progression of gastric cancer mediating miR-7/FAK/AKT signaling pathway remain unclear. PURPOSE: To investigate the molecular mechanism and effects of BAI inhibiting progression of gastric cancer mediating miR-7/FAK/AKT signaling pathway. METHODS: Gastric cancer cell lines with FAK knockdown and overexpression were constructed by lentivirus transfection. After BAI treatment, the effects of FAK protein on proliferation, metastasis and angiogenesis of gastric cancer cells were detected by MTT, EdU, colony formation, wound healing, transwell and Matrigel tube formation assays. In vivo experiment was performed by xenograft model. Immunofluorescence and western blot assay were used to detect the effects of FAK protein on the expression levels of EMT markers and PI3K/AKT signaling pathway related proteins. qRT-PCR and luciferase reporter assay were used to clarify the targeting relationship between miR-7 and FAK. RESULTS: BAI can regulate FAK to affect proliferation, metastasis and angiogenesis of gastric cancer cells through PI3K/AKT signaling pathway. qRT-PCR showed BAI can upregulated the expression of miR-7 and luciferase reporter assay showed the targeting relationship between miR-7 and FAK. Additionally, miR-7 mediates cell proliferation, metastasis and angiogenesis by directly targeting FAK 3'UTR to inhibit FAK expression. CONCLUSION: BAI repressing progression of gastric cancer mediating miR-7/FAK/AKT signaling pathway.

CD44 enhances adriamycin resistance in chronic myelogenous leukaemia cells K562.

INTRODUCTION: To investigate CD44 effects on the adriamycin-resistant in chronic myelogenous leukaemia cells K562, we explored the role of CD44 in the K562 cells migration and apoptosis. METHODS: GeneChip® screening is used for elucidating various chemoresistance-related gene expression in the adriamycin-resistant leukaemia cells K562/ADR. We constructed K562/CD44 cells by transfection of an EGFP-SV40-CD44 plasmid, and adriamycin-resistant ability was confirmed by detecting migration and apoptosis-related proteins and mRNA expression using Western blotting and Real-time PCR respectively. RESULTS: K562/CD44 cells were generated by the transfection of an EGFP-SV40-CD44 plasmid with high CD44 expression. mRNA expression levels of CD44 and P-glycoprotein (P-gp), along with the proliferation rate, were increased, while the apoptosis rate of K562/CD44 cells was decreased. Migration-associated proteins such as MMP-2 and MMP-9 were upregulated, whereas apoptosis-related protein Bax was downregulated and Bcl-2 protein was not significantly altered in the K562/CD44 cells. CONCLUSIONS: CD44 might be involved in adriamycin resistance via regulation of P-gp, MMP-2, MMP-9, and Bcl-2/Bax.

Identification of small compounds regulating the secretion of extracellular vesicles via a TIM4-affinity ELISA.

Extracellular vesicles (EVs) are secreted from most cells and play important roles in cell-cell communication by transporting proteins, lipids, and nucleic acids. As the involvement of EVs in diseases has become apparent, druggable regulators of EV secretion are required. However, the lack of a highly sensitive EV detection system has made the development of EV regulators difficult. We developed an ELISA system using a high-affinity phosphatidylserine-binder TIM4 to capture EVs and screened a 1567-compound library. Consequently, we identified one inhibitor and three activators of EV secretion in a variety of cells. The inhibitor, apoptosis activator 2, suppressed EV secretion via a different mechanism and had a broader cellular specificity than GW4869. Moreover, the three activators, namely cucurbitacin B, gossypol, and obatoclax, had broad cellular specificity, including HEK293T cells and human mesenchymal stem cells (hMSCs). In vitro bioactivity assays revealed that some regulators control EV secretion from glioblastoma and hMSCs, which induces angiogenesis and protects cardiomyocytes against apoptosis, respectively. In conclusion, we developed a high-throughput method to detect EVs with high sensitivity and versatility, and identified four compounds that can regulate the bioactivity of EVs.

Baicalein Inhibits Gastric Cancer Cell Proliferation and Migration through a FAK Interaction via AKT/mTOR Signaling.

Gastric cancer is a common malignancy worldwide and is associated with high morbidity and mortality rates. However, very little is known about the underlying mechanism in human gastric cancer cells. Baicalein (BAI), a widely used Chinese herbal medicine, has shown anticancer effects on many types of human cancer cell lines. Here, we investigated the molecular mechanisms underlying BAI action on gastric cancer cell proliferation and migration. The results showed that BAI can expressively inhibit cell proliferation, colony-forming ability and migration ability in a dose-dependent manner, while in the meantime inducing cell apoptosis. Additionally, we found that BAI can suppress FAK and the phosphorylation of PI3K, AKT and mTOR in a dose-dependent manner. Furthermore, BAI significantly inhibited tumor growth in a xenograft model. Also, BAI can inhibit the proliferation and migration of gastric cancer cells and the expression of the pathway by downregulating the expression of FAK. In short, we demonstrated that BAI inhibited gastric cancer cell proliferation and migration through FAK interaction via downregulation in AKT/mTOR signaling, which signifies that BAI may be a latent therapeutic factor for the treatment of gastric cancer patients and that FAK might be a hopeful therapy target for the disease.

[Expression of Clec2 in Patients with Myelodysplastic Syndrome and Its Correlation with TPO].

OBJECTIVE: To explore the expression of clec2 in patients with myelodysplastic syndrome (MDS) and to analyze its correlation with TPO. METHODS: The expression of plasma clec2 in 47 patients with MDS and 20 normal controls was detected by ELISA, and the correlation between the clinical characteristics of MDS patients and clec2 expression was analyzed. Meanwhile, the expression level of plasma TPO in 42 patients with MDS was detected, and its correlation with clec2 was analyzed. RESULTS: The expression of clec2 was 171.5.2±57.6 ng/ml in normal controls and 347.9±121.5 ng/ml in patients with MDS (P＜0.01). The expression level was 375.4±124.3 ng/ml in the initial treatment patients and 288.6±98.7 ng/ml in the re-treatment patients (P＜0.05). There was no relationship between clec2 and sex, age, number of peripheral blood cells, bone marrow blast cells. However, further analysis showed that there was a positive correlation between clec2 and TPO (r=0.419, P＜0.01). CONCLUSION: Clec2 is highly expresses in MDS patients and positively correlates with TPO. The interaction between clec2 and TPO may play an important role in the occurrence and development of MDS, which may be the new molecular mechanism and mechanism of targeted therapy.

Angiogenic cytokines can reflect the synovitis severity and treatment response to biologics in rheumatoid arthritis.

Angiogenesis and synoviocyte hyperplasia, called 'pannus,' are pathologic hallmarks of rheumatoid arthritis (RA). To determine the clinical significance of angiogenic cytokines in RA, the levels of pro-angiogenic cytokines, including VEGF, placenta growth factor (PlGF), and IL-6, were measured in the synovial fluid (SF, n = 54) and sera of RA patients (n = 157) using ELISA. Patients (n = 103) with disease activity score 28 (DAS28) > 3.2, which indicates moderate to high RA activity, underwent follow-up blood sampling at 6 months after treatment with conventional disease-modifying anti-rheumatic drugs (c-DMARD) or biologic DMARD (b-DMARD) including an anti-TNFα antibody, an anti-IL-6 antibody, and abatacept. Ultrasonography (US) was performed on affected joints to define the synovitis severity at the time of sampling. Consequently, in the SF of RA patients, PlGF and IL-6 levels correlated well with synovitis severity determined by US. In RA sera, VEGF and IL-6 levels were elevated in proportion to synovitis severity, correlating with conventional markers for disease activity, including ESR, CRP, and DAS28. In c-DMARD users (n = 53), serially monitored levels of serum VEGF, IL-6, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) all decreased in good and moderate responders but not in nonresponders. In b-DMARD users (n = 49), only serum VEGF well represented the treatment response, while CRP nonspecifically decreased irrespective of the treatment outcome. By multivariable analysis, serum ΔVEGF, but not ΔESR or ΔCRP, was an independent factor associated with good and moderate responses to DMARD. In summary, the angiogenic cytokines PlGF and VEGF represent the synovitis severity of RA assessed by US. In patients receiving b-DMARD, serum VEGF may be more valuable than CRP in reflecting the treatment response.

Plasma soluble C-type lectin-like receptor-2 is associated with the risk of coronary artery disease.

Accumulating evidence suggests that C-type lectin-like receptor-2 (CLEC-2) plays an important role in atherothrombosis. In this case-control study, we investigated the association between CLEC-2 and incidence of coronary artery disease (CAD). A total of 216 patients, including 14 cases of stable angina pectoris (SAP, non-ACS) and 202 cases of acute coronary syndrome (ACS), and 89 non-CAD control subjects were enrolled. Plasma levels of soluble CLEC-2 (sCLEC-2) were measured using the enzyme-linked immunosorbent assay (ELISA). Compared with the control group (65.69 (55.36-143.22) pg/mL), the plasma levels of sCLEC-2 were significantly increased in patients with CAD (133.67 (88.76-220.09) pg/mL) and ACS (134.16 (88.88-225.81) pg/mL). The multivariate adjusted odds ratios (95% confidence interval) of CAD reached 2.01 (1.52-2.66) (Ptrend < 0.001) for each 1-quartile increase in sCLEC-2. Restricted cubic splines showed a positive dose-response association between sCLEC2 and CAD incidence (Plinearity < 0.001). The addition of sCLEC-2 to conventional risk factors improved the C statistic (0.821 vs. 0.761, P = 0.004) and reclassification ability (net reclassification improvement: 57.45%, P < 0.001; integrated discrimination improvement: 8.27%, P < 0.001) for CAD. In conclusion, high plasma sCLEC-2 is independently associated with CAD risk, and the prognostic value of sCLEC-2 may be evaluated in future prospective studies.

Yu Jin Pulvis inhibits carbon tetrachloride-induced liver fibrosis by blocking the MAPK and PI3K/Akt signaling pathways.

Traditional Chinese medicine theory indicates that Yu Jin Pulvis (YJP) could prevent liver fibrosis progression and this has been verified in liver fibrosis patients. However, the mechanism underlying the protective effects of YJP against liver fibrosis remains unclear. While different signaling pathways are involved in liver fibrosis progression, mitogen-activated protein kinase (MAPK) and phosphoinositide-3-kinase-protein kinase B/Akt (PI3K/Akt) are the most crucial. To determine whether YJP regulates these signaling pathways to prevent liver fibrosis, we used a mouse model of liver fibrosis induced by intraperitoneal injection of carbon tetrachloride (CCl4). Mice were randomly divided into normal, CCl4, YJP (300 mg/kg), CCl4+YJP (100, 200, and 300 mg/kg), and two positive control silybin (100 mg/kg) and Fuzheng Huayu (FZHY) capsule (2 g/kg) groups. The mice were gavaged daily for 6 weeks. Then liver fibrosis markers; tissue morphology; serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and proinflammatory cytokine levels; and expression of α-smooth muscle actin (α-SMA) and collagen type I (Col1) were examined to determine liver fibrosis progression. Liver injury and collagen deposition were significantly reduced in the YJP treatment group compared with the CCl4 group. Furthermore, the expression of phosphorylated-extracellular-signal-regulated kinase (p-ERK), p-jun N-terminal kinase (p-JNK), p-P38MAPK, p-PI3K and p-Akt was decreased by YJP treatment compared with CCl4 treatment. Collectively, these results demonstrate the antifibrosis effect of YJP on CCl4-induced liver fibrosis in mice, mediated through blockade of the MAPK and PI3K/Akt signaling pathways. Therefore, YJP has therapeutic potential against liver fibrosis.

[Baicalein inhibits PI3K/AKT signaling pathway and induces autophagy of MGC-803 cells].

Objective To investigate the effect of baicalein (BAI) on autophagy in gastric cancer cell line MGC-803. Methods MGC-803 cells were treated with 0, 5, 15, 25, 50 µmol/L BAI for 24, 48, 72 hours. The proliferation activity of MGC-803 cells was detected by MTT assay. Acridine orange (AO) staining combined with immunofluorescence cytochemical staining was performed to observe the expression of microtubule-associated protein 1 light chain 3 (LC3) and P62 to determine autophagy in MGC-803 cells. The protein levels of LC3, P62, phosphatidylinositol 3-kinase (PI3K), phosphorylated PI3K (p-PI3K), AKT, and p-AKT were detected by Western blot analysis. Results Compared with the control group, BAI significantly inhibited the proliferation of MGC-803 cells in a time- and dose-dependent manner. BAI-treated MGC-803 cells showed a significant increase in acid lysosomes and increased LC3 expression. BAI treatment significantly decreased phosphorylation of PI3K and AKT proteins, increased the ratio of LC3-II/LC3-I and up-regulated the expression of P62 protein. Conclusion Baicalein could inhibit PI3K/AKT signaling pathway and induce autophagy in MGC-803 cells.

Platelet-type 12-lipoxygenase accelerates tumor promotion of mouse epidermal cells through enhancement of cloning efficiency.

Accumulating evidence suggests that platelet-type 12-lipoxygenase (p12-LOX) plays an important role in tumor development. However, how p12-LOX contributes to tumorigenesis is still not understood. The role of p12-LOX was therefore examined in tumor promotion using mouse epidermal JB6 P+ cells that are sensitive to 12-O-tetradecanoylphorbol-13-acetate-induced transformation. The expression of p12-LOX was significantly higher in JB6 P+ cells than in JB6 P- cells that were resistant to transformation, and its expression was further increased by tumor necrosis factor (TNF)-alpha. Importantly, the inhibition of p12-LOX in JB6 P+ cells by baicalein, a specific inhibitor or small interfering RNA significantly suppressed TPA-induced transformation. Moreover, treatment with 12(S)-hydroxyeicosatetraenoic acid (HETE), a metabolite of p12-LOX, enhanced TPA-induced neoplastic transformation either in the presence or absence of baicalein. These results indicate that p12-LOX is required for tumor promotion of epidermal cells and that 12(S)-HETE functions as a rate-limiting factor. Notably, treatment with baicalein significantly suppressed the proliferation of JB6 P+ cells when cells were seeded at a low density in a culture plate. Moreover, the cloning efficiency of JB6 P+ cells was dramatically decreased by inhibition of p12-LOX. In contrast, baicalein treatment did not affect the cloning efficiency of most malignant cancer cells. These results indicate that p12-LOX is induced by the inflammatory cytokine TNF-alpha in the early stage of tumorigenesis, and is required for tumor promotion through enhancing efficient proliferation of a small number of initiated cells. The present results suggest that the p12-LOX pathway may be an effective target of chemoprevention for skin carcinogenesis.

[Relationship among the Oxygen Concentration, Reactive Oxygen Species and the Biological Characteristics of Mouse Bone Marrow Hematopoietic Stem Cells].

OBJECTIVE: To investigate the effects of oxygen concentration and reactive oxygen species (ROS) on the biological characteristics of hematopoietic stem cells (HSC) and to analyzed the relationship among the oxygen concentration, ROS and the biological characteristics of mouse HSC through simulation of oxygen environment experienced by PB HSC during transplantation. METHODS: The detection of reactive oxygen species (ROS), in vitro amplification, directional differentiation (BFU-E, CFU-GM, CFU-Mix), homing of adhesion molecules (CXCR4, CD44, VLA4, VLA5, P-selectin), migration rate, CFU-S of NOD/SCID mice irradiated with sublethal dose were performed to study the effect of oxgen concentration and reactive oxygen species on the biological characteristics of mouse BM-HSC and the relationship among them. RESULTS: The oxygen concentrations lower than normal oxygen concentration (especially hypoxic oxygen environment) could reduce ROS level and amplify more Lin(-) c-kit(+) Sca-1(+) BM HSC, which was more helpful to the growth of various colonies (BFU-E, CFU-GM, CFU-Mix) and to maintain the migratory ability of HSC, thus promoting CFU-S growth significantly after the transplantation of HSC in NOD/SCID mice irradiated by a sublethal dose. BM HSC exposed to oxygen environments of normal, inconstant oxygen level and strenuously thanging of oxygen concentration could result in higher level of ROS, at the same time, the above-mentioned features and functional indicators were relatively lower. CONCLUSION: The ROS levels of BM HSC in PB HSCT are closely related to the concentrations and stability of oxygen surrounding the cells. High oxygen concentration results in an high level of ROS, which is not helpful to maintain the biological characteristics of BM HSC. Before transplantation and in vitro amplification, the application of antioxidancs and constant oxygen level environments may be beneficial for transplantation of BMMSC.

SCF/C-KIT signaling modulates tryptase expression in acute myeloid leukemia cells.

Tryptase is a serine protease with a variety of biological functions. Recently, elevated serum tryptase has been detected in certain patients with acute myeloid leukemia (AML). However, the underlying mechanism for the regulation of tryptase expression remains elusive. In this study, we aimed to investigate the role of stem cell factor (SCF)/C-KIT signaling in regulating the expression of tryptase in AML cells. We found a significant positive correlation between tryptase and C-KIT expression levels in AML patients. Furthermore, real-time PCR, Western blot and ELISA analysis showed that SCF upregulated tryptase mRNA and protein expression in U937 cells, and that this effect was abolished by pretreatment with PD98059 and SB230580. In addition, levels of phosphorylated ERK1/2 and p38MAPK correlated with tryptase levels. Taken together, these data suggest that the expression of tryptase is regulated by SCF/C-KIT signaling via the ERK1/2 and p38MAPK pathways.

Ezrin overexpression predicts the poor prognosis of gastric adenocarcinoma.

BACKGROUND: Ezrin is a cytoskeletal protein that is involved in tumor growth and invasion. It has been suggested that Ezrin expression plays an important role in tumor metastasis. This study is aimed to investigate the clinicopathological significance of Ezrin overexpression in gastric adenocarcinomas. METHODS: Ezrin protein expression was examined by immunohistochemistry in 26 normal gastric mucosa, 32 dysplasia, and 277 gastric adenocarcinomas. The relationship between Ezrin expression and the clinicopathological features of gastric cancers was analyzed. In addition, a gastric cancer cell line, MKN-1, was also used for immunofluorescence staining to evaluate the distribution of Ezrin protein. RESULTS: Ezrin protein located in the cytoplasm and/or membrane in the migrating gastric cancer cells, and it mainly concentrated at the protrusion site; however, only cytoplasmic distribution was observed in the non-migrating cancer cells by immunofluorescence staining. The positive rate of Ezrin protein expression was significantly higher in gastric adenocarcinoma and dysplasia compared with that in the normal gastric mucosa. Moreover, expression frequency of Ezrin protein increased significantly in lymph node metastasis and late clinical stages. Consistently, strong expression of Ezrin was significantly correlated with poor prognosis of gastric cancer. CONCLUSION: The detection of Ezrin expression can be used as the marker for early diagnosis and prognosis of gastric adenocarcinoma. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/2303598677653946.