Next-generation diagnostic pathology / 中华病理学杂志

With the technological progresses and applications of human genome sequencing, bioinformatics analysis and data mining, and molecular pathology and artificial intelligence-assisted pathological diagnosis, the development of clinical medicine is moving towards the era of precision diagnosis and treatment. In the context of this era, the traditional diagnostic pathology is facing unprecedented opportunities and challenges in our history and is striving towards the "next-generation diagnostic pathology" (NGDP). NGDP is based on histomorphology and clinical data, and characterized by the combination of molecular detection and bioinformatics analysis, intelligent sampling and process quality control, intelligent diagnosis and remote consultation, lesion visualization and "non-invasive" pathology as well as other innovative cutting edge interdisciplinary technologies. The NGDP reports will include the results from multi-omics and cross-scale integrated diagnosis for final diagnosis. NGDP will also be applied for predicting disease progression and outcomes, and determining optional therapeutics as well as assessing treatment responses, so that a novel "golden standard" of disease diagnosis can be established. In the near fature, it is necessary to stimulate the innovative vitality of pathology disciplines, accelerate the maturity and application for NGDP, update the theory and technical system of pathology, and perform its important applicable role in the prevention, diagnosis, treatment of diseases so that the futher development of clinical medicine will be promoted and the strategy for maintenance of being healthy in China will be served.

Resistance to apoptosis should not be taken as a hallmark of cancer / 癌症

In the research community, resistance to apoptosis is often considered a hallmark of cancer. However, pathologists who diagnose cancer via microscope often see the opposite. Indeed, increased apoptosis and mitosis are usually observed simultaneously in cancerous lesions. Studies have shown that increased apoptosis is associated with cancer aggressiveness and poor clinical outcome. Furthermore, overexpression of Bcl-2, an antiapoptotic protein, is linked with better survival of cancer patients. Conversely, Bax, CD95, Caspase-3, and other apoptosis-inducing proteins have been found to promote carcinogenesis. This notion of the role of apoptosis in cancer is not new; cancer cells were found to be short-lived 88 years ago. Given these observations, resistance to apoptosis should not be considered a hallmark of cancer.

Contribution of cancer stem cells to tumor vasculogenic mimicry

Vasculogenic mimicry (VM), a newly-defined pattern of tumor blood supply, provides a special passage without endothelial cells and is conspicuously different from angiogenesis and vasculogenesis. The biological features of the tumor cells that form VM remain unknown. Cancer stem cells (CSCs) are believed to be tumor-initiating cells, capable of self-renewal and multipotent differentiation, which resemble normal stem cells in phenotype and function. Recently CSCs have been shown to contribute to VM formation as well as angiogenesis. These findings challenge the previous understanding of the cellular basis of VM formation. In this review, we present evidence for participation of CSCs in VM formation. We also discuss the potential mechanisms and possible interaction of CSCs with various elements in tumor microenvironment niche. Based on the importance of VM in tumor progression, it constitutes a novel therapeutic target for cancer.

Protective effects of enalaprilat on the myocardial kinetics in rats at early stage of severe scald / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the therapeutic effects of Enalaprilat on the myocardial kinetics in rats at early stage of severe scald.</p><p><b>METHODS</b>Eighty-four SD rats were inflicted with 30% TBSA full-thickness scald, and randomly divided into scald (S, with intraperitoneal injection of isotonic saline according to Parkland formula, n=30), L (n=30), M (n=12) and H (n=12) groups. The rats in L,M,H groups were intraperitoneally injected with 1,2,4 mg/kg Enalaprilat. Other 6 healthy rats were enrolled into study as control (C group). The myocardial kinetic parameters including left ventricular systolic pressure (LVSP), left ventricular end diastolic pressure (LVEDP), +/- dp/dt max and the levels of A II in myocardium were observed at 1,3,6,12 and 24 post scald hour (PBH) in L and S groups,and at 6,12 PBH in M and H groups. The above indices in C group were also examined.</p><p><b>RESULTS</b>The levels of LVSP, LVEDP, +/- dp/dt max in C group were higher than those in other groups during 3-24 PBH (P < 0.05 or P < 0.01), while those in L,M,H groups were obviously higher than those in S group (P < 0.05 or P < 0.01). The level of +/- dp/dt max in H group at 6,12 PBH were obviously lower than those in L and M groups. The level of A II in S group at 1 PBH was (53.0 +/- 2.6) pg/200 mg, which was significantly higher than thatin C group [(14.8 +/- 0.7) pg/200 mg, P < 0.05 or P < 0.01]; it peaked at6 PBH and lowered afterwards, and they were significantly higher than that in C group at 24 PBH (P < 0.01). The levels of A II in L group during 3-24 PBH were obviously higher than those in C group (P < 0.01), which were also lower than those in S group. The level of A II in S group was significantly higher than in L,M,H groups at 6 PBH [(145.2 +/- 14.5) pg/200 mg. vs. (65.1 +/- 0.9) pg/200 mg, (53.6 +/- 1.1) pg/200 mg, (34.2 +/- 0.9) pg/200 mg, respectively, P < 0.01].</p><p><b>CONCLUSION</b>Myocardium can be obviously damaged at early stage after severe scald,cardiac function is impaired. Enalaprilat injection (especially at low dose) can significantly ameliorate the myocardial kinetics indices, and it seems to exert a protective effect on cardiac function.</p>

Vasculogenic potential of endothelial progenitor cells derived from human umbilical cord blood and their roles in neovascularization of malignant glioma / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate vasculogenic potential of endothelial progenitor cells (EPCs) derived from human umbilical cord blood and their contribution to the neovascularization of malignant glioma in vivo.</p><p><b>METHODS</b>EPCs were isolated from human umbilical cord blood by density gradient centrifugation. After 7-10 days of culture, EPCs were investigated for CD34 and VEGFR-2 expression by direct immunofluoresent staining. The proliferative activity, migratory capability and forming capillary-like tubules were also monitored after stimulation with VEGF(50 mg/L) in vitro. Moreover, EPCs were administered into tumor-bearing mice, and the tumor and mouse organs were examined under confocal laser scanning microscope to visualize the distribution and localization of transplanted EPCs. In order to quantity the incorporation of EPCs into tumor vessels, cryosections of the tumor tissue were double-labelled with antihuman CD31 and anti-mouse CD31.</p><p><b>RESULTS</b>After 7 to 10 days of culture, EPCs assumed cobblestone-like monolayer growth pattern with nearly complete confluence, and expressed CD34 and VEGFR-2. Significant proliferative activity, increased migratory capability and forming capillary-like tubules were observed when stimulated with VEGF. The transplanted EPCs in vivo specifically homed to solid tumor tissue and incorporated into the tumor's endothelium. Quantitative analysis revealed that human EPCs contributed significantly to tumor neovascularization by incorporation into tumor vasculature (18.68 +/- 1.32)% of the total vessels.</p><p><b>CONCLUSION</b>EPCs possess the potential to form neovascular network in tumor and play a role in the phenotypical heterogeneity of tumor microvascular architecture.</p>

Effect of nordy on the function of endothelial progenitor cells from human umbilical cord blood induced by vascular endothelial growth factor / 药学学报

This study is to investigate whether the synthesized chiral compound Nordy has influence on the function of endothelial progenitor cells (EPCs) from human umbilical cord blood induced by vascular endothelial growth factor (VEGF). EPCs were isolated from human umbilical cord blood by density gradient centrifugation. After cultured for 7 -10 days, EPCs were prepared for detecting effect of Nordy on proliferation, migration and tubule-forming activity in Matrigel induced by VEGF. Incubation of EPCs with 100 micromol L(-1) Nordy for 24 h initially inhibited the proliferative capacity of EPCs induced by VEGF (P <0.05). Moreover, 25 -50 micromol L(-1) Nordy also exhibited inhibitory effect at 48 -72 h. In addition, 25 - 100 micromol L(-1) Nordy impaired EPCs migratory and tubule-forming capacity in vitro (P < 0.05). Nordy could inhibit in EPCs the functions of proliferation, migration and tubulogenesis induced by VEGF in vitro, which might be a possible mechanism of its anti-EPCs effects.

Activation of CXCR4 in human glioma stem cells promotes tumor angiogenesis / 中华病理学杂志

<p><b>OBJECTIVE</b>To isolate, culture and identify glioma stem cells from human malignant glioma cell line U87, and investigate the changes of pro-angiogenic factors production by glioma stem cells followed by activation of CXCR4 and observe their tumorigenesis as well as the expression of vascular endothelial growth factor when implanted into nude mice.</p><p><b>METHODS</b>The ratio of CD133 positive cells was detected by flow cytometry. Magnetic separation of CD133 positive cells was carried out on the magnetic cell sorting system (MACS). Expression of nestin, glial fibrillary acidic protein (GFAP) and CXCR4 on tumorspheres was detected by indirect immunofluorescence under confocal laser scanning microscopy. The functional activation of CXCR4 was assessed by calcium mobilization experiments. ELISA was used to detect the production of vascular endothelial growth factor (VEGF) and interleukin-8 (IL-8) in conditioned medium. Glioma stem cells were implanted into nude mice to assess their tumorigenesis ability and the expression of VEGF.</p><p><b>RESULTS</b>The ratio of CD133 positive cells with stem cell property was 0.5% in U87 cells. Activation of CXCR4 on glioma stem cells induced calcium mobilization and increased VEGF and IL-8 protein secretion. CD133 positive cells secreted more VEGF and IL-8 than their negative counterparts in vitro. Tumors derived from CD133 positive cells grew more rapidly and expressed elevated level of VEGF than their negative counterparts.</p><p><b>CONCLUSIONS</b>There are a small fraction of glioma stem cells in human glioblastoma cell line U87. Expressing functional CXCR4 and secreting more pro-angiogenic factors may be involved in tumor angiogenesis mediated by glioma stem cells.</p>

Effect of nordy on biological behaviors of malignant glioma cell line U87MG and the analysis of differential expression proteome / 中华病理学杂志

<p><b>OBJECTIVE</b>To explore effects of nordy on biological behaviors of human malignant glioblastoma cell line U87MG in vitro and transplanted tumor in vivo, and to identify the differential proteome upon Nordy induced differentiation.</p><p><b>METHODS</b>Glioblastoma U87MG cells were induced to differentiate by synthetic lipoxygenase inhibitor, Nordy. The drug was also given via peritoneal injection to nude mice (27 mg/kg body weight) bearing orthotopic transplanted tumors of U87MG cells in the brain. The tumor volumes and GFAP expression were measured. Total proteins of U87MG cells after Nordy treatment were analysed by two-dimensional gel electrophoresis. PDQuest 7.1 computer software was used to compare protein profiles of the treated cells with that of untreated control. Differentially expressed proteins were then selected and characterized by matrix assisted laser desorption ionization-time of flight-mass spectrometry. The functional aspects of these proteins were analyzed by bioinformatics.</p><p><b>RESULTS</b>Nordy suppressed both the proliferation of U87MG cells in vitro and the tumor growth of orthotopic transplanted tumors in vivo (P < 0.01). The differentially expressed proteins induced by Nordy included proliferation-associated gene A, alternative splicing factor ASF-3, eukaryotic translation initiation factor 5A, coffilin 1 (non-muscle), beta galactoside binding lectin, glyceraldehyde-3-phosphate dehydrogenase, enolase 1 and an unknown protein.</p><p><b>CONCLUSIONS</b>Nordy promotes the differentiation of glioblastoma cells, by which it may serve as a therapeutic agent. Various proteins identified during Nordy-induced differentiation are involved in the cell proliferation, metabolism, differentiation, apoptosis and gene transcription.</p>

Effect of nordy on FPR function of malignant human glioma cell line U87 / 药学学报

Nordy is a synthesized chrial compound. To investigate the effects of nordy (25 - 100 micromol x L(-1)) on the function of formylpeptide receptor (FPR) of malignant human glioma cells, human glioblastoma cell line U87 was used to detect its proliferation, migration, calcium mobilization, vascular endothelial growth factor (VEGF) mRNA and protein levels after activation of FPR by its agonist N-formyl-methionyl-leucyl-phenylalanine (fMLF). Cell proliferation, migration ability, VEGF mRNA, VEGF protein and calcium mobilization were evaluated by cell counting, chemotaxis assay, RT-PCR, ELISA and spectrometry. Nordy (50 - 100 micromol x L(-1)) potently inhibited the proliferation, migration and calcium mobilization of U87 cells induced by fMLF (P < 0.05). Moreover, 100 micromol x L(-1) nordy showed a significantly impaired VEGF mRNA expression and protein secretion induced by fMLF (P < 0.05). Nordy could inhibit FPR functioning in glioma cell proliferation, migration and angiogenesis, which might be a possible mechanism of its anti-cancer effects.

VEGF-induced tubulogenesis of endothelial cells from human brain malignant glioma in the three dimentional model / 中华病理学杂志

<p><b>OBJECTIVE</b>To compare the tubulogenesis capability of malignant glioma-derived microvessel endothelial cells (GDMEC) from human brain with that of ECV304 cells in a three dimentional model and to explore the significance of GDMEC in the study on angiogenesis.</p><p><b>METHODS</b>The GDMEC were isolated from malignant gliomas of human brain and purified by selective binding to the monoclonal antibody against CD105 bound to the magnetic MACS MicroBeads. GDMEC and endothelial-like cell line ECV304 were compared with their capabilities of formatting tubule-like structure (TLS) in the three dimentional collagen matrix, with or without inducement by various concentration of vascular endothelial growth factor (VEGF).</p><p><b>RESULTS</b>The obtained GDMEC had a high purification (98%) and could be successfully cultured in vitro. GDMECs formed more TLS than ECV304 cells of the same number and at the same time points. VEGF could induce rapid formation of TLS in a dose-dependent manner, however, ECV304 cells were less response to VEGF stimulation.</p><p><b>CONCLUSIONS</b>GDMEC could maintain their endothelial characteristics and potential capability of angiogenesis. They were more response to VEGF than ECV304, therefore, more suitable for in vitro studies on tumor angiogenesis.</p>

Effects of ectopic glial fibrillary acidic protein/green fluorescent protein gene expression on cellular differentiation and proliferation of human glioma cell line / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate the biological effects of ectopic overexpression of glial fibrillary acidic protein (GFAP) in human malignant glioma cell line, and to explore new method of differentiation induction gene therapy for gliomas.</p><p><b>METHODS</b>A eukaryotic expression vector containing 1.1 kb GFAP cDNA fused with green fluorescent protein (GFP) gene, pIRGFP-GFAP, was transfected into human SHG-44 glioma cell line by lipofectamine. The expression of GFAP/GFP gene and their proteins were detected by fluorescent real-time monitoring, in situ hybridization, Western blot and immunocytochemistry. Flow cytometry, soft agar colony formation and other methods were used to measure the effects of exogenous GFAP expression on cell cycle progression, morphology and growth features of the transfected glioma cells.</p><p><b>RESULTS</b>The expressions of GFAP mRNA and its protein were markedly increased in SHG-44 cells upon stable transfection with pIRGFP/GFAP vector. Profound morphological changes in these cells were also observed, including the formation of abundant, stellate and thin cytoplasmic processes and a reduction of atypia. Cell proliferation rate and its tumorigenecity on soft agar were markedly reduced. In addition, cell cycle analysis revealed a percentage decrease of cell populations at G0/G1 and G2/M phases.</p><p><b>CONCLUSIONS</b>Ectopic overexpression of GFAP gene could significantly suppress the growth of SHG-44 malignant glioma cells along with an induction of differentiation. These results imply that forced over-expression of GFAP gene may provide a new strategy for glioma therapy.</p>

The significance of beta-catenin and matrix metalloproteinase-7 expression in colorectal adenoma and carcinoma / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate the relationship between beta-catenin and matrix metalloproteinase-7 (MMP-7) expression and development/biologic behavior of human colorectal cancer.</p><p><b>METHODS</b>Immunohistochemical study for beta-catenin and MMP-7 was carried out on colorectal adenoma-carcinoma tissue microarrays and results analyzed.</p><p><b>RESULTS</b>The nuclear beta-catenin expression rate was 35.9% in adenoma with malignant transformation, significantly higher than that in adenoma (16.7%) and carcinoma (19.7%) (both P < 0.05). The cytoplasmic and nuclear beta-catenin expression rate in adenoma with severe dysplasia was significantly higher than that in adenoma with mild dysplasia (both P < 0.05). The nuclear beta-catenin expression rate in adenocarcinomas of the ulcerative type, with lymph node metastasis and in the late tumor stages were all significantly higher than that in adenocarcinomas of the polypoid type, with negative lymph node and in the early tumor stages (P < 0.05 or P < 0.01). The MMP-7 expression rate in adenocarcinoma (69.2%) was significantly higher than that in normal colorectal mucosa (15.0%), adenoma (35.0%) and adenoma with malignant transformation (46.2%, P < 0.05 or P < 0.01). The MMP-7 expression rate in ulcerative type adenocarcinoma with lymph node metastasis and in late tumor stages was significantly higher than that in polypoid type adenocarcinoma with negative lymph node and in early tumor stages (all P < 0.05). The cytoplasmic and nuclear beta-catenin expression was thus in positive correlation with the expression of MMP-7 (both P < 0.01).</p><p><b>CONCLUSIONS</b>The cytoplasmic and nuclear beta-catenin expression, probably an early event, was related to the development of colorectal cancer. beta-catenin may enhance the degradative function of the target gene MMP-7 through nuclear translocation and may further facilitate local invasion and metastasis by the colorectal cancer cells.</p>

Expression of some oncogenes and point mutation of c-Ha-ras1 during hepatocarcinogenesis in rats / 第三军医大学学报

Objective　To study the expressions of oncogenes c-Ha-ras, c-ki-ras, pan-ras and c-myc and point mutation of c-Ha-ras1 during hepatocarcinogenesis in rats. Methods　Immunohistochemistry, in situ hybridization and microdissection of tissue (MDT)-PCR-SSCP were used to detect the oncogene expressions and point mutation of c-Ha-ras1 in both Solt-Farber model and DEN-induced liver cancer model. Results　The overexpression of c-Ha-ras was closely associated with the formation and proliferation of the precancerous basophilic hepatocyte foci, while that of c-myc with the growth of the oval cell foci. The abnormalities of IGF-Ⅱ played an important role in the evolution of precancerous foci/nodules towards hepatocellular carcinoma (HCC). The overexpression of fms was only associated with HCC of some rats. Conclusion　Hepatocarcinogenesis in rats was related with the overexpression of c-Ha-ras, c-myc, IGF-Ⅱand fms and the point mutation of c-Ha-ras1, and overexpression of these oncogenes was associated with morphological evolution.

Quantitative study on morphologic features and proliferative activity during DEN-induced hepatocarcinogenesis in rats / 第三军医大学学报

Objective　To explore the relationship between morphologic evolution and proliferative activity during hepatocarcinogenesis in rats. Methods　Imaging analysis technique was used to detect the morphologic parameters of cells in hepatic lesions in both Solt-Farber model and diethylnitrosamine (DEN)-induced liver cancer model. Immunohistochemistry was employed to detect proliferating cell nuclear antigen (PCNA) and bromodeoxyuridine (BrdU). Results　The oval cells were identified as irregular small proliferating cells in size of one-eighth of and with a nucleus/cytoplasm ratio of 6 times of the normal hepatocyte by image analysis. The morphometric parameters of basophil hepatocyte in precancerous foci and nodule were similar to those of the liver cancer cell. PCNA and BrdU positive cells were mainly localized within the proliferative foci and hepatocellular carcinoma (HCC) tissues. There was a better consistency between the development of hepatic lesions and cellular proliferative activity. Conclusion　The morphologic evolution is closely related to proliferative activity during hepatocarcinogenesis in rats.

Effect of nordihydroguaiaretic acid on the morphological changes of endothelial cells in vitro / 第三军医大学学报

Objective　To investigate morphological changes of endothelial cells after nordihydroguaiaretic acid (NDGA) treatment in vitro. Methods　The morphological changes of human umbilical vein endothelial cells (HUVEC) cell line ECV-304 and the cell apoptosis rate in sub-G0 phase were observed with invert, light and electron microscope and flow cytometry after NDGA treatment at different concentrations or with PBS (0.01 mol/L) as control. Results　①After the treatment of NDGA at 50～200 μmol/L for 1～3 d or up to 8 d at 100 μmol/L, ECV-304 cells tended to elongate into a shuttle-like sparse appearance and those in mitosis were decreased, indicating the suppression of cell proliferation. All these alteration was in a time-and dose-dependent manner. ②NDGA-treated ECV-304 cells displayed morphological features of apoptosis, especially at the 48th h after the treatment. With flow cytometry, the cells in sub-G0 phase were significantly increased, and reached its peak at hour 12 (20.42%) after NDGA treatment. In addition, the degeneration and necrosis of ECV-304 cells were related to the concentrations of NDGA. Conclusion　NDGA can inhibit the proliferation and growth of endothhelial cells, and induce apopotosis, which might also inhibit angiogenesis.

Inhibitory effects of angiogenesis inhibitor TNP-470 on growth of a human malignant glioma cell line SHG-44 and its xenografted tumor / 第三军医大学学报

Objective　To investigate the effects of TNP-470 on the growth of a human malignant glioma cell line SHG-44 in vivo and in vitro. Methods　The colorimetric MTT assay, soft agar culture, flow cytometry，light and electron microscopy were used to determine the proliferation, the cloning efficiency, cell cycle and the morphological changes of SHG-44 cells as well as the growth of its xenografted tumor. Results　TNP-470 (20～2 000 ng/ml) significantly inhibited the proliferation of SHG-44 cells in vitro (the 50% inhibitory concentration was 200 ng/ml). Cloning efficiency reduced obviously. The number of cells in G0/G1 phase increased, while that in S, G2/M phases decreased significantly. Weight and volume of xenografted tumors treated with TNP-470 (30 mg/kg, injected subcutaneously every other day) reduced notably. Furthermore, there were necrotic area and apoptosis in the tumor. No severe side effect of TNP-470 was found in this study. Conclusion　The inhibitory effect of TNP-470 on the growth of SHG-44 cells correlates with its functions of regulating cell cycle and inducing apoptosis, which suggests that the angiogenesis inhibitor TNP-470 has strong inhibitory effect on human malignant gliomas.

Effect of nordihydroguaiaretic acid on expressions of VEGF and its receptor KDR in vitro / 第三军医大学学报

Objective　To explore the effect of nordihydroguaiaretic acid (NDGA) on the expressions of vascular endothelial growth factor (VEGF) and its receptor, kinase-inserted domain containing receptor(KDR) and the possible mechanism. Methods　The expression of VEGF in human malignant glioma cell line SHG-44 and that of KDR in human umbilical vein endothelial cell (HUVEC) line ECV-304 were observed 1～3 d after NDGA treatment with immunohistochemistry, in situ hybridization and image analysis. Results　The expression of VEGF was declined at protein or mRNA levels in SHG-44 cells after treated with 100 μmol/L NDGA for 1 to 3 d. The expression of KDR in endothelial cells with 100 μmol/L NDGA treatment for 1 to 3 d was decreased too, in a more obvious way compared with the decline of VEGF expression in SHG-44 cells. Conclusion　The results suggest that NDGA inhibits the expression of VEGF in glioma cells as well as that of VEGF receptor KDR in endothelial cells, which may be the important molecular mechanism of anti-angiogenesis of NDGA.

Significance of bcl-2 and c-myc gene expression in nordihydroguaiaretic acid-induced apoptosis of a human malignant glioma cell line / 第三军医大学学报

Objective　To investigate the changes and their significance of bcl-2 and c-myc in nordihydroguaiaretic acid (NDGA)-induced apoptosis of human malignant glioma cell line SHG-44. Methods　The apoptosis of SHG-44 cells was observed with light and electron microscopy and TUNEL method. The expression of bcl-2 and c-myc gene was measured with immunohistochemistry, in situ hybridization and image analysis. Results ① The SHG-44 cell apoptosis was induced by NDGA at a concentration lower than 200 μmol/L in a time-dependent manner. ② The expressions of bcl-2 and c-myc gene in SHG-44 cells were decreased after the treatment of 100 μmol/L NDGA with the elapse of time, indicating a close association with cell apoptosis. ③ The expressions of bcl-2 and c-myc mRNA in SHG-44 cells were decreased after the treatment with 100μmol/L NDGA, which was apparently consistent with the immunohistochemical results. Conclusion　The NDGA-induced apoptosis in human malignant glioma cells might be related with the down-regulated expressions of bcl-2 and c-myc gene. The exact mechanism needs further research.

Roles of cyclin-dependent kinase 4 (CDK4) in nordihydroguaiaretic acid-induced inhibitory effect on proliferation of human malignant glioma cells / 第三军医大学学报

Objective　To investigate roles of cyclin-dependent kinase 4 (CDK4) in nordihydroguaiaretic acid (NDGA)-induced inhibitory effect on proliferation of human malignant glioma cells. Methods　The techniques of cell culture, cell counts, flow cytometry, immunoprecipitation, immunohistochemistry and image analysis were employed in this study. Results　①A concentration-dependent inhibition of proliferation was demonstrated in the SHG-44 cells incubated for 24 hours in the presence of NDGA, and cell proliferation was blocked in the G1→S phase. ②The activity of CDK4 was decreased apparently in the SHG-44 cells treated for 24 hours with 10 to 200 μmol/L NDGA in a concentration-dependent way. ③The expression of CDK4 gene was downregulated in the cells after NDGA treatment. Conclusion　CDK4 plays an important role in NDGA-induced inhibition of glioma cell proliferation.

Effects of nordihydroguaiaretic acid on the expression of GFAP gene of human malignant glioma cell line SHG-44 / 第三军医大学学报

Objective　To investigate the expression of glial fibrillary acidic protein (GFAP) gene and its significance in the process of glioma cell differentiation induced by nordihydroguaiaretic acid (NDGA). Methods　Immunohistochemistry (IHC) and in situ hybridization were used to detect the expression changes of GFAP protein and GFAP mRNA qualitatively and quantitatively. Results　The expression levels of GFAP protein and GFAP mRNA in NDGA treatment group were significantly increased compared with the control group (P<0.01). Conclusion　NDGA could induce GFAP gene in malignant glioma cells and the up-regulation of this gene expression might be one of the mechanisms by which NDGA induces glioma differentiation.