miR-182-5p Promotes Growth in Oral Squamous Cell Carcinoma by Inhibiting CAMK2N1.

BACKGROUND/AIMS: Emerging evidence suggests that the propagation of oral squamous cell carcinoma (OSCC) is influenced by the abnormal expression of microRNAs (miRNAs). This study aimed to characterize the involvement of miR-182-5p in OSCC by targeting the calcium/ calmodulin-dependent protein kinase II inhibitor CAMK2N1. METHODS: miR-182-5p expression was quantified in OSCC tissues and cell lines with reverse transcription polymerase chain reaction (RT-PCR). Cell colony formation, Cell Counting Kit-8 (CCK-8), Ki-67, and nude mouse xenograft assays were used to characterize the role of miR-182-5p in the proliferation of OSCC. A miR-182-5p target gene was identified with western blotting, RT-PCR, and luciferase activity assays. OSCC patient survival based on CAMK2N1 expression was also analyzed. RESULTS: miR-182-5p was up-regulated in in vitro cell lines and in vivo clinical OSCC samples. CCK-8, colony formation, and Ki-67 assays revealed that miR-182-5p promoted the growth and proliferation of OSCC cells. miR-182-5p directly targeted CAMK2N1, as evidenced by luciferase assays and target prediction algorithms. CAMK2N1 operated as a tumor suppressor gene in patients with OSCC. Down-regulating miR-182-5p expression in the CAL-27 cell line restored CAMK2N1-mediated OSCC cell proliferation. miR-182-5p expression inhibited the activation of AKT, ERK1/2, and NF-κB. Mice injected with CAL-27 cells transfected with miR-182-5p-inhibitor demonstrated a significant increase in tumor size and weight and increased CAMK2N1 mRNA and protein expression compared with the miR-negative control group. CONCLUSION: The miR-182-5p-CAMK2N1 pathway can be potentially targeted to regulate the proliferation of OSCC cells.

CD44 collaborates with ERBB2 mediate radiation resistance via p38 phosphorylation and DNA homologous recombination pathway in prostate cancer.

CD44, a glycoprotein, has been reported to have relationship with resistance to radiation in prostate cancer (Cap) cells. However, its molecular mechanism remains unknown. In this study, we demonstrated that inhibited CD44 enhanced the radiosentivity in Cap cells. It has been hypothesized that CD44 combine with ERBB2 and activate downstream phosphated protein to mediate DNA damage repair. Therefore, we conducted a detailed analysis of effects of radiation by clonogenic assay and immunofluorescence stain for p-H2AX foci. The downstream of CD44/ERBB2 and DNA damage repair proteins was detected by western blot. The results reveal that CD44 interacted with ERBB2, the downstream of CD44/ERBB2 was p-p38 when Cap cells were irradiated. Among the pathways, homologous recombination (HR) related proteins Mre11 and Rad50 were involved in CD44/ERBB2/p-p38 mediated radioresistance in Cap. In conclusion, CD44 could stabilize ERBB2 and co-activate p-p38 expression then promote the DNA damage repair by HR pathway, which finally contribute to the radioresistance of CaP.

Relationship between driver gene mutations, their relative protein expressions and survival in non-small cell lung carcinoma in Macao.

OBJECTIVES: We report the status of most common gene mutations in non-small cell lung carcinoma (NSCLC) in Macao, and explore the relationship between each gene mutation and clinicopathologic features and survival. METHODS: EGFR, KRAS and BRAF mutations were detected by PCR in 122 cases of NSCLC. ALK translocation and MET amplification were detected by fluorescence in situ hybridization (FISH). MET and thyroid transcription factor (TTF-1) were investigated by immunohistochemistry. Clinical data were collected for analyzing their correlation with the gene mutations. RESULTS: The mutation of EGFR, KRAS and BRAF was detected in 48 (39.3%), 13 (10.7%) and 3 (2.5%) of 122 cases of NSCLC, respectively. ALK translocation and MET amplification were detected in 7 (5.7%) and 3 cases (2.5%). The rate of EGFR mutation was significantly higher in female and non-smoker patients. In TTF-1 positive cases EGFR mutation was more frequent. Age of the patients over 62-year old was correlated with KRAS mutations. The concordance between ALK IHC and FISH was 58.3%. The MET protein in the cases with MET amplification was 100% positive. The survival was lower in the patients with positive MET protein than those with negative. MET protein was an independent prognostic factor for NSCLC. CONCLUSIONS: EGFR mutation occurred frequently in the female never smoke patients with NSCLC. KRAS mutation was more common in old patients. Negative MET protein expression could be used as a negative predictive marker of MET amplification. MET protein expression was an independent prognostic factor for NSCLC.

Tetrandrine inhibits glioma stem-like cells by repressing ß-catenin expression.

Cancer stem cells (CSCs) in glioma are often responsible for relapse and resistance to therapy. The purpose of the present study was to confirm the self-renewal and migration inhibitory effects of tetrandrine (Tet), which is a compound extracted from the dried root of Stephania tetrandra S. Moore, toward glioma stem-like cells (GSLCs) and to examine the associated molecular mechanisms. Using a neurosphere culture technique, we enriched the GSLC population from the human glioblastoma cell lines U87 and U251. Cells were analyzed using cell counting kit-8 (CCK-8), western blotting, flow cytometry, transwell assay and immunofluorescence staining. GSLCs displayed properties of neural stem cells, including elevated expression of the cancer stem cell marker ALDH1 and ß-catenin. We found that Tet treatment decreased sphere formation in GSLCs in a dose-dependent manner using tumor spheroid formation assay. The GSK3ß inhibitor BIO maintained sphere formation and migration capacity in GSLCs, whereas the ß-catenin/TCF transcription inhibitor ICG-001 decreased sphere formation and the migration capacity of GSLCs. The proportion of apoptotic GSLCs also increased in response to ICG-001 treatment. These results indicate that ß-catenin activity is vital in maintaining neural stem cell traits of GSLCs. Tet inhibits cell viability, neurosphere formation and migration of GSLCs in vitro. Importantly, Tet treatment significantly repressed the nuclear translocation and expression of ß-catenin and induced apoptosis in GSLCs, as indicated in part by the upregulation of Bax, the cleavage of PARP and the downregulation of Bcl-2. The present study demonstrates that the inhibition of ß-catenin in CSCs by Tet could be an effective strategy for the treatment of glioma.

Tetrandrine Exerts a Radiosensitization Effect on Human Glioma through Inhibiting Proliferation by Attenuating ERK Phosphorylation.

Tetrandrine (Tet), a bisbenzylisoquinoline alkaloid, has been reported to have a radiosensitization effect on tumors. However, its effects on human glioma and the specific molecular mechanisms of these effects remain unknown. In this study, we demonstrated that Tet has a radiosensitization effect on human glioma cells. It has been hypothesized that Tet has a radiosensitization effect on glioma cells by affecting the glioma cell cycle and DNA repair mechanism and that ERK mediates these activities. Therefore, we conducted detailed analyses of the effects of Tet on the cell cycle by performing flow cytometric analysis and on DNA repair by detecting the expression of phosphorylated H2AX by immunofluorescence. We used western blot analysis to investigate the role of ERK in the effect of Tet on the cell cycle and DNA repair. The results revealed that Tet exerts its radiosensitization effect on glioma cells by inhibiting proliferation and decreasing the expression of phosphorylated ERK and its downstream proteins. In summary, our data indicate that ERK is involved in Tet-induced radiosensitization of glioma cells via inhibition of glioma cell proliferation or of the cell cycle at G0/G1 phase.

Tetrandrine suppresses human glioma growth by inhibiting cell survival, proliferation and tumour angiogenesis through attenuating STAT3 phosphorylation.

Tetrandrine (Tet), a bisbenzylisoquinoline alkaloid, has been reported to possess anti-tumour activity. However, its effects on human glioma remain unknown. In this study, we demonstrated that Tet inhibited human glioma cell growth in vitro and in vivo. It has been hypothesised that Tet inhibits glioma growth by affecting glioma cell survival, proliferation and vasculature in and around the xenograft tumour in the chick CAM model and signal transducer and activator of transcription 3 (STAT3) mediated these activities. Therefore, we conducted a detailed analysis of the inhibitory effects of Tet on cell survival using a TUNEL assay and flow cytometric analysis; on cell proliferation based on the expression of proliferating cell nuclear antigen; and on angiogenesis using a CAM anti-angiogenesis assay. We used western blotting to investigate the role of STAT3 on the anti-glioma activities of Tet. The results revealed that Tet inhibited survival and proliferation in human glioma cells, impaired tumour angiogenesis and decreased the expression of phosphorylated STAT3 and its downstream proteins. In sum, our data indicate that STAT3 is involved in Tet-induced the regression of glioma growth by activating tumour cell apoptosis, inhibiting glioma cell proliferation and inhibiting angiogenesis.

EGCG inhibits properties of glioma stem-like cells and synergizes with temozolomide through downregulation of P-glycoprotein inhibition.

RATIONAL: Combination therapy to inhibit cancer stem cells may have important clinical implications. Here, we examine the molecular mechanisms by which epigallocatechin gallate (EGCG), a bioactive polyphenol in green tea, inhibits the stem cell characteristics of glioma stem-like cells (GSLCs) and synergizes with temozolomide (TMZ), a DNA-methylating agent commonly used as first-line chemotherapy in gliomas. GSLCs were enriched from the human glioblastoma cell line U87 using neurosphere culture. Cells were analyzed using flow cytometry, quantitative PCR, and western blotting. Compared to U87 cells, a higher percentage of U87 GSLCs remained in the G0/G1 phase, with downregulation of the cell-cycle protein CylinD1 and overexpression of stem cell markers CD133 and ALDH1. The drug-resistance gene ABCB1 (but not ABCG2 or MGMT) also showed high mRNA and protein expression. The resistance index of U87 GSLCs against TMZ and carmustine (BCNU) was 3.0 and 16.8, respectively. These results indicate that U87 GSLCs possess neural stem cell and drug-resistance properties. Interestingly, EGCG treatment inhibited cell viability, neurosphere formation, and migration in this cell model. EGCG also induced apoptosis, downregulation of p-Akt and Bcl-2, and cleaving PARP in a dose-dependent manner. Importantly, EGCG treatment significantly downregulated P-glycoprotein expression but not that of ABCG2 or MGMT and simultaneously enhanced sensitivity to TMZ. Our study demonstrates that the use of EGCG alone or in combination with TMZ may be an effective therapeutic strategy for glioma.

Zoledronic acid exerts antitumor effects in NB4 acute promyelocytic leukemia cells by inducing apoptosis and S phase arrest.

The aim of this study was to investigate the antitumor effect of zoledronic acid (ZOL) in the NB4 human acute promyelocytic leukemia (APL) cell line and explore the potential mechanism of action of this compound. NB4 cells were exposed to various concentrations (0-200µM) of ZOL. Cell viability was measured by MTS assay. The extent of cell apoptosis and distribution of cells in the different phases of the cell cycle were analyzed with flow cytometry. The expression of apoptosis- and cell cycle-related proteins was assayed by Western blot. The combined effect of ZOL and arsenic trioxide (ATO) on the proliferation of NB4 cells was also determined. The results of this study indicate that ZOL inhibits cell proliferation in a time- and dose-dependent fashion and also induces apoptosis and S phase arrest in a dose-dependent manner. The Western blot analysis confirmed the induction of apoptosis and S phase arrest, revealing that the pro-apoptosis proteins Bax, Puma and activated caspase-9 were upregulated and the anti-apoptosis proteins Bcl-2 and Bcl-xL were downregulated. ZOL at a concentration of 50µM synergized with 0.5µM ATO on the growth inhibition of NB4 cells. Taken together, our data indicate that ZOL exerts a potent antitumor effect on NB4 cells by inducing apoptosis and cell cycle arrest, and that ZOL can synergize with the traditional chemotherapy drug ATO.

4E-BP1 regulates the sensitivity of human glioma cells to chemotherapy through PI3K/Akt/mTOR-independent pathway.

Drug resistance is one of the most formidable obstacles for treatment of glioma. Eukaryotic initiation factor 4E-binding protein (4E-BP1), a key component in the rate-limiting step of protein translation initiation, is closely associated with poor prognosis in multiple tumor types. However, it is unclear whether 4E-BP1 is involved in the drug resistance of human glioma. Herein we show that the expression of 4E-BP1 in human SWOZ2-BCNU drug-resistant glioma cells is significantly lower than that of the parent SWOZ2 cell line. Moreover, down-regulation of 4E-BP1 by short interfering RNA significantly impaired the sensitivity of SWOZ2 and U251 cells to carmustine (BCNU). Furthermore, overexpression of 4E-BP1 with plasmid transfection regained this sensitivity. Clinical studies showed that the expression levels of 4E-BP1 in primary glioma tissues were markedly higher than those of recrudescent glioma tissues. Taken together, our results suggest that 4E-BP1 is a novel protein that contributes to acquired drug resistance and it may be a potential target for reversing drug resistance in human glioma.

Epithelial-to-mesenchymal transition is involved in BCNU resistance in human glioma cells.

Chemotherapy has been considered as an effective treatment for malignant glioma; however, it becomes increasingly ineffective with tumor progression. Epithelial-to-mesenchymal transition (EMT) is a process whereby cells acquire morphologic and molecular alterations that facilitate tumor metastasis and progression. Emerging evidence associates chemoresistance with the acquisition of EMT in cancer. However, it is not clear whether this phenomenon is involved in glioma. We used the previously established human glioma cell lines SWOZ1, SWOZ2 and SWOZ2-BCNU to assess cellular morphology, molecular changes, migration and invasion. We found that BCNU-resistant cells showed multiple drug resistance and phenotypic changes consistent with EMT, including spindle-shaped morphology and enhanced pseudopodia formation. Decreased expression of the epithelial adhesion molecule E-cadherin and increased expression of the mesenchymal marker vimentin were observed in BCNU-resistant SWOZ1 and SWOZ2-BCNU cells compared to SWOZ2 cells. Migratory and metastatic potentials were markedly enhanced in SWOZ1 and SWOZ2-BCNU cells compared to SWOZ2 cells. These data suggest that there is a possible link between drug resistance and EMT induction in glioma cells. Gaining further insight into the mechanisms underlying chemoresistance and EMT may enable the restoration of chemosensitivity or suppression of metastasis.

Role of PTEN in cholera toxin-induced SWO­38 glioma cell differentiation.

Malignant gliomas persist as a major disease responsible for high morbidity and mortality rates in adults. Differentiation therapy has emerged as a promising treatment modality. Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) gene function is commonly lost in primary gliomas, particularly in glioblastomas, and this is associated with tumor differentiation. PTEN gene deletion is one of the main molecular events in gliomas. In this study, we aimed to explore the effect and mechanisms of PTEN on cholera toxin (CT)­induced SWO-38 glioma cell differentiation. It has been shown that transfection of the exogenous PTEN gene induces glioma cell differentiation; however, the underlying mechanism remains to be elucidated. Results of the present study showed that CT-induced SWO-38 glioma cell differentiation was characterized by morphological changes, the increased expression of glial fibrillary acidic protein (GFAP), an accumulation of cells in the G0/G1 phase of the cell cycle, the decreased expression of cyclin D1 and a decreased invasion and migration capacity. Silencing of the PTEN protein using RNA interference resulted in suppressed cell differentiation. Furthermore, inhibition of the PI3K/AKT pathway by the inhibitor LY294002 led to attenuated differentiation, while differentiation remained stable with the inhibition of the MAPK/ERK pathway by PD0325901. Thus, PTEN may be important in glioma cell differentiation.

[Effects of human umbilical cord mesenchymal stem cells in the treatment of paraquat-induced lung injury].

OBJECTIVE: To evaluate the clinical effect and safety of human umbilical cord mesenchymal stem cells (HUCMSCs) in the treatment of lung injury caused by acute paraquat poisoning. METHODS: Thirteen patients with lung injury caused by acute paraquat poisoning, who were admitted to Guangzhou No. 12 People's Hospital from December 2008 to December 2012, were divided into HUCMSC group (n = 5) and control group (n = 8). All patients received conventional treatment, while the HUCMSC group was treated with HUCMSCs as an addition. Sequential Organ Failure Assessment (SOFA) system, which was created by the Infection Section of European Society of Intensive Care Medicine, and Acute Physiology and Chronic Health Evaluation II were used to acquire the SOFA scores of patients. The lung injury was evaluated with lung injury score (LIS). The two groups were compared with respect to maximum SOFA scores at 1, 3, 5, 7, 14, and 15 days after paraquat poisoning. RESULTS: The HUCMSC group showed significantly lower maximum SOFA scores than the control group at 15d after poisoning (1.80 ± 2.05 vs 13.50 ± 7.59, P < 0.05). The LISs of the HUCMSC group after treatment (0.45 ± 0.27) were significantly lower than those of the HUCMSC group before treatment (1.15 ± 0.34) and those of the control group after treatment (2.94 ± 1.20) (P < 0.01). In the HUCMSC group, all patients survived, and they complained no discomfort and showed normal liver, kidney, and lung functions in reexamination; one patient showed incompletely absorbed shadow in the posterior segment of the left lower lobe of the lung during lung CT scan, and no abnormal findings were seen in other patients. In the control group, one patient survived, and others died. No adverse reactions, such as chill and fever, were presented in the HUCMSC group. CONCLUSION: HUCMSCs show promise for clinical application in the treatment of lung injury caused by acute paraquat poisoning.

Glycogen Synthase Kinase 3ß Inhibitor (2'Z,3'E)-6-Bromo-indirubin- 3'-Oxime Enhances Drug Resistance to 5-Fluorouracil Chemotherapy in Colon Cancer Cells.

OBJECTIVE: To explore the effects and mechanism of glycogen synthase kinase 3ß (GSK-3ß) inhibitor (2'Z,3'E)-6-bromo-indirubin-3'-oxime (BIO) on drug resistance in colon cancer cells. METHODS: The colon cancer SW480 and SW620 cells were treated with BIO, 5-fluorouracil (5-FU) and BIO/5-FU, separately. Cell cycle distribution, apoptosis level and efflux ability of rhodamine 123 (Rh123) were detected by flow cytometry. The protein expressions of P-glycoprotein (P-gp), multidrug resistance protein 2 (MRP2), thymidylate synthase (TS), ß-catenin, E2F-1 and Bcl-2 were detected by Western blot. ß-catenin and P-gp were stained with double immunofluorescence and observed under a confocal microscope. RESULTS: BIO up-regulated ß-catenin, P-gp, MRP2 and TS, enhanced the efflux ability of Rh123, decreased Bcl-2 protein and gave the opposite effect to E2F-1 protein in SW480 and SW620 cells. Furthermore, BIO significantly inhibited cell apoptosis, increased S and G(2)/M phase cells, and reduced the cell apoptosis induced by 5-FU in SW480 cells, whereas the effects were slight or not obvious in SW620 cells. CONCLUSION: GSK-3ß was involved in drug resistance regulation, and activation of ß-catenin and inhibition of E2F-1 may be the most responsible for the enhancement of 5-FU chemotherapy resistance induced by GSK-3ß inhibitor BIO in colon cancer.

Silencing of MGMT with small interference RNA reversed resistance in human BCUN-resistant glioma cell lines.

BACKGROUND: Our previous study had cloned two glioma cell lines SWOZ1 and SWOZ2 isolated from parental glioma cell line SWO38. The 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) resistance of SWOZ1 was higher than that of SWOZ2. Since O6-methylguanine-DNA methyltransferase (MGMT) was thought to be closely related to BCNU resistance in glioma, this study aimed to explore the function of MGMT in glioma resistant to BCNU. METHODS: A BCNU resistant glioma cell line SWOZ2-BCNU was established. The expression of MGMT was detected in SWOZ1, SWOZ2 and SWOZ2-BCNU. Small interferencing RNA targeting MGMT was used to silence the expression of MGMT in resistant cell lines SWOZ1 and SWOZ2-BCNU. The cytotoxicity of BCNU to these cells was measured using the cell counting kit-8 assay. Statistical analysis was carried out by one-way analysis of variance in statistical package SPSS 13.0. RESULTS: The resistance of SWOZ1 and SWOZ2-BCNU against BCNU was 4.9-fold and 5.3-fold higher than that of SWOZ2. The results of quantitative RT-PCR and Western blotting confirmed that MGMT was both significantly increased in SWOZ1 and SWOZ2-BCNU compared to SOWZ2. After transfection with small interferencing RNA targeting MGMT, a decreased level of MGMT mRNA expression in SWOZ1 and SWOZ2-BCNU for more than 75% compared to negative control was found and confirmed by Western blotting. As a result, the resistance against BCNU was reversed for about 50% both in the BCNU-resistant cell lines SWOZ1 and SWOZ2-BCNU. CONCLUSIONS: Silencing MGMT with specific small interferencing RNA can reverse the BCNU resistant phenotype in these glioma cell lines. MGMT may play an important role both in intrinsic and acquired BCNU-resistance in glioma.

[Hepatocyte growth factor combined with autologous bone marrow mesenchymal stem cell transplantation for treatment of silicosis].

OBJECTIVE: To evaluate the potential role of hepatocyte growth factor (HGF) combined with bone marrow mesenchymal stem cells (BMSC) autograft for the treatment of silicosis. METHODS: Bone marrow (100 ml) was aspirated from a severe silicosis patient. BMSCs isolated, purified and cultured in vitro. When BMSC came to 70% confluence at passage 3, the culture medium was added liposomes (lipo2000) and plasmid-HGF (p-HGF) and cultured for 2 d. HGF-MSCSs (5 × 10(7) cells) were resuspended in 50 ml 0.9% sodium chloride (NS) and infused Intravenous drip at 3 consecutive times (once a week). Clinical follow-up were performed before and after treatment: (1) pulmonary high-kV X-ray, chest CT examination; (2) pulmonary function test; (3) determination of serum ceruloplasmin. RESULTS: The symptoms such as coughing, chest tightness disappeared at 12 months after treatment. Pulmonary function tests showed significant changes after treatment: forced vital capacity (FVC) increased from 64.6% to 81.0%, forced expiratory volume in one second (FEV(1.0)) increased from 68.7% to 90.1%, 1 second rate (FEV(1.0)/FVC%) reduced from 111.6% to 107.1%, the maximum mid-expiratory flow (FEF(25%∼75%) decreased from 100.2% to 94.6%, forced expiratory vital capacity 75% of the moment bit of gas flow (MEF(75%)) increased from 99.2% to 113.5%, forced expiratory vital capacity 50% of the moment bit of gas flow (MEF(50%)) increased from 125.3% to 130.2%, forced expiratory vital capacity 25% of the moment bit of gas flow (MEF(25%)) reduced from 86.9% to 71.7%; serum ceruloplasmin levels decreased from 690 mg/L to 180.6 mg/L; lung high-kV X-ray at 1st review showed that diffuse lung nodules had been absorbed and getting smaller than before treatment; chest CT showed that the distribution and number of small nodules at double lung fields decreased than before treatment. CONCLUSION: HGF combined with BMSC transplantation may have some potential role for the treatment of silicosis patients.

Metastasis-associated protein 1 induces VEGF-C and facilitates lymphangiogenesis in colorectal cancer.

AIM: To study the correlation between high metastasis-associated protein 1 (MTA1) expression and lymphangiogenesis in colorectal cancer (CRC) and its role in production of vascular endothelial growth factor-C(VEGF-C). METHODS: Impact of high MTA1 and VEGF-C expression levels on disease progression and lymphovascular density (LVD, D2-40-immunolabeled) in 81 cases of human CRC was evaluated by immunohistochemistry. VEGF-C mRNA and protein expressions in human LoVo and HCT116 cell lines were detected by real-time polymerase chain reaction and Western blotting, respectively, with a stable expression vector or siRNA. RESULTS: The elevated MTA1 and VEGF-C expression levels were correlated with lymph node metastasis and Dukes stages (P < 0.05). Additionally, high MTA1 expression level was correlated with a large tumor size (P < 0.05). A significant correlation was found between MTA1 and VEGF-C protein expressions in tumor cells (r = 0.371, P < 0.05). Similar to the VEGF-C expression level, high MTA1 expression level was correlated with high LVD in CRC (P < 0.05). Furthermore, over-expression of MTA1 significantly enhanced the VEGF-C mRNA and protein expression levels, whereas siRNAs - knocked down MTA1 decreased the VEGF-C expression level. CONCLUSION: MTA1, as a regulator of tumor-associated lymphangiogenesis, promotes lymphangiogenesis in CRC by mediating the VEGF-C expression.

[The comparative study of quartz dust and bleomycin-induced pulmonary fibrosis in rats].

OBJECTIVE: To compare the pulmonary alveolitis and the early fibrosis of pulmonary fibrosis induced by quartz dust and bleomycin in rats, and investigate their mechanism. METHODS: The female rats were divided into three groups: control group exposed to normal saline by the trachea; SiO2 group exposed to SiO2 by the trachea; BLM group exposed to BLM A5 by the trachea. Each half of the animals were sacrificed on the 7th and 14th day after exposure. The lungs of rats were collected to observe pulmonary alveolitis by HE staining and to observe fibrosis by saturated picric acid sirius red staining. The expression of tumor necrosis factor-alpha (TNF-alpha) and CD68 in pulmonary tissues were analyzed quantitatively by immunohistochemistry and image analysis system. RESULTS: (1) The alveolitis and pulmonary fibrosis of rats in both SiO2 group and BLM group were became more serious gradually over time, HE staining under light microscope showed that BLM group on the 7th day had the most obvious alveolitis (2.814 +/- 0.832), the saturated picric acid sirius red staining under polarized light showed that BLM group on the 14th day had the worst pulmonary fibrosis (1284.57 +/- 554.72), which were significantly higher than those (103.69 +/- 18.29 and 111.78 +/- 37.45) in control group and SiO2 group on the 7th day (P < 0.05). (2) The results of immunohistochemistry examination indicated that the expression (17.100 +/- 1.831) of TNF-alpha in the BLM group on the 7th day was significantly higher than those (0.451 +/- 0.441, 7.909 +/- 1.275 and 13.506 +/- 1.454) in control group, SiO2 group on 7th day and BLM group on 14th day (P < 0.05). The expression (22.778 +/- 2.512) of TNF-alpha in the SiO2 group on the 14th day was significantly higher than those in control group, SiO2 group on 7th day and BLM group on 14th day (P < 0.05). The expression (134.941 +/- 35.951) of CD68 in the SiO2 group on the 14th day was significantly higher than those in control group, SiO2 group on 7th day and BLM group on 14th day (P < 0.05). CONCLUSION: The early alveolitis of BLM-induced lung injury model was more serious than that of SiO2-induced lung injury model, and the fibrosis process of BLM-induced lung injury model was earlier than that of SiO2-induced lung injury model. TNF-alpha plays an important role in the course of both models, but macrophages is involved in SiO2-induced pulmonary in a more continuous way than in BLM-induced pulmonary fibrosis.

[The experimental study of suppressing silicosis fibrosis].

OBJECTIVE: To compare the difference of effects on SiO(2)-induced alveolitis and early fibrosis between bone marrow-derived mesenchymal-like stem cells (BM-MSCs) and BM-MSCs transfected by pcDNA3.1-HGF and to explore the mechanism of this effects. METHODS: The Primary BM-MSCs from Wistar male young rats were cultured and labeled by 4, 6-diamidino-2-phenylindole (DAPI). Fifty Wistar rats were randomly divided into 3 groups:model group (10 rats),which was administered with SiO(2) by the trache, the next day,injected PBS via the tail vein; BM-MSCs group (20 rats),which was administered with SiO(2) by the trache, the next day,injected with 1 ml suspension of BM-MSCs via the tail vein; pcDNA3.1-HGF plus BM-MSC group (20 rats),which was administered with SiO(2) by the trache, the next day,injected with 1 ml suspension of BM-MSCs transfected by pcDNA3.1-HGF via the tail vein. On the 14th and 28th days after treatment, half of the animals were sacrificed, respectively, and the lungs were harvested for frozen section to observe the cell marked by DAPI. HE staining under a fluorescent microscope, and to observe the pulmonary alveolitis and fibrosis by HE and Masson staining under a light microscope. Western blot assay was used to detect the expression of HGF in rat lungs. The expression levels of tumor necrosis factor-α (TNF-α) in pulmonary tissues were analyzed quantitatively by ELISA. The contents of HYP in pulmonary tissues were analyzed quantitatively by sample hydrolysis method. RESULTS: On the 14th and 28th days after treatment, the scores of pulmonary alveolitis and early fibrosis in pcDNA3.1-HGF plus BM-MSCs group were 2.36 ± 0.17, 2.8 ± 0.14 and 0.1 ± 0.11, 1.16 ± 0.13, which were significantly lower than those (1.68 ± 0.17, 1.58 ± 0.31 and 0.54 ± 0.15, 1.36 ± 0.13) in BM-MSCs group, also which were significantly lower those (2.36 ± 0.17, 2.80 ± 0.14 and 0.64 ± 0.09, 1.84 ± 0.17) in model group (P < 0.05); On the 14th and 28th days after treatment, the TNF-α contents of pulmonary tissues in pcDNA3.1-HGF plus BM-MSCs group were 280.4 ± 23.11 and 249.78 ± 22.33 pg/mg, which were significantly lower than those (341.58 ± 35.34, 442.29 ± 36.76 pg/mg and 319.51 ± 17.84, 348.53 ± 33.95 pg/mg) in BM-MSCs and model groups (P < 0.05); On the 14th and 28th days after treatment, the HYP contents of pulmonary tissues in pcDNA3.1-HGF plus BM-MSCs group were 0.46 ± 0.04 and 0.65 ± 0.05 µg/mg, which were significantly lower than those (0.63 ± 0.04, 1.04 ± 0.07 µg/mg and 0.72 ± 0.60, 1.39 ± 0.60 µg/mg) in BM-MSCs and model groups (P < 0.05). CONCLUSION: The effects of BM-MSCs transfected by pcDNA3.1-HGF on suppressing pulmonary alveolitis and early fibrosis induced by SiO2 were better than those of BM-MSCs. The mechanism may be associated with the reduced pulmonary inflammation.

Role of DJ-1-induced PTEN down-regulation in migration and invasion of human glioma cells.

BACKGROUND AND OBJECTIVE: DJ-1, a suppressor of PTEN, promotes metastasis of different tumors, but its function and mechanisms in glioma metastasis remain unclear. This study aimed to investigate the effect of the DJ-1 protein on the migration and invasion of human glioma cells, and to explore potential mechanisms. METHODS: The eukaryotic expression vector pEGFP/DJ-1 and small interfering RNA (siRNA) were constructed and transfected into human glioma SWO-38 cells. The expression of DJ-1 and PTEN in SWO-38 cells were detected by Western blot. Cell migration and invasion were detected by transwell assay. RESULTS: After transfection of pEGFP/DJ-1, the expression of DJ-1 (1.28 ± 0.15 vs. 0.89 ± 0.04, P < 0.05) and focal adhesion kinase (FAK) phosphorylation (0.76 ± 0.12 vs. 0.51 ± 0.04, P < 0.05) were increased, whereas the expression of PTEN (0.74 ± 0.2 vs. 1.04 ± 0.14, P < 0.05) was suppressed. After transfection of DJ-1 siRNA, both DJ-1 (0.33 ± 0.04 vs. 0.88 ± 0.06, P < 0.05) and p-FAK levels (0.33 ± 0.01 vs. 0.44 ± 0.05, P < 0.05) were decreased, but PTEN expression (1.1 ± 0.06 vs. 0.81 ± 0.12, P < 0.05) was increased. Transwell assay data showed that pEGFP/DJ-1 transfection promoted SWO-38 cell migration (57.2 ± 6.50 vs. 40.4 ± 5.0, P < 0.05) and invasion (54.6 ± 4.9 vs. 27 ± 6.7, P < 0.05), whereas DJ-1 siRNA transfection inhibited SWO-38 cells migration (54.4 ± 6.9 vs. 73.4 ± 7.6, < 0.05) and invasion (44.6 ± 5.8 vs. 69.2 ± 9.2, P < 0.05). CONCLUSION: Over-expression of DJ-1 promotes SWO-38 cell migration and invasion possibly through the DJ-1 and the PTEN/FAK pathway.

Association of ABCC2 and CDDP-Resistance in Two Sublines Resistant to CDDP Derived from a Human Nasopharyngeal Carcinoma Cell Line.

Cisplatin (CDDP) is one of the most active drugs to treat nasopharyngeal carcinoma (NPC) patients. To further understand the mechanisms of CDDP-resistance in NPC, two CDDP-resistant sublines (CNE2-CDDP and CNE2-CDDP-5Fu) derived from parental NPC cell line CNE2 were established. It was found that at the IC50 level, the resistance of CNE2-CDDP and CNE2-CDDP-5Fu against CDDP was 2.63-fold and 5.35-fold stronger than that of parental CNE2, respectively. Of the four ABC transporters (ABCB1, ABCC1, ABCC2 and ABCG2) related to MDR, only ABCC2 was found to be elevated both in CDDP-resistant sublines, with ABCC2 located in nucleus of CNE2-CDDP-5Fu but not in CNE2-CDDP and parental CNE2. Further research showed that compared to untreated CNE2, the intracellular levels of CDDP were decreased by 2.03-fold in CNE2-CDDP and 2.78-fold in CNE2-CDDP-5Fu. After treatment with PSC833, a modulator of MDR associated transporters including ABCC2, the intracellular level of CDDP was increased in CDDP-resistant sublines, and the resistance to CDDP was partially reversed from 2.63-fold to 1.62-fold in CNE2-CDDP and from 5.35-fold to 4.62-fold in CNE2-CDDP-5Fu. These data indicate that ABCC2 may play an important role in NPC resistant to CDDP.