miR-21 may acts as an oncomir by targeting RECK, a matrix metalloproteinase regulator, in prostate cancer

Background: Prognosis of prostate cancer (PCa) is based mainly in histological aspects together with PSA serum levels that not always reflect the real aggressive potential of the neoplasia. The micro RNA (miRNA) mir-21 has been shown to regulate invasiveness in cancer through translational repression of the Metaloproteinase (MMP) inhibitor RECK. Our aim is to investigate the levels of expression of RECK and miR-21 in PCa comparing with classical prognostic factors and disease outcome and also test if RECK is a target of miR-21 in in vitro study using PCa cell line. Materials and methods: To determine if RECK is a target of miR-21 in prostate cancer we performed an in vitro assay with PCa cell line DU-145 transfected with pre-miR-21 and anti-miR-21. To determine miR-21 and RECK expression levels in PCa samples we performed quantitative real-time polymerase chain reaction (qRT-PCR). Results: The in vitro assays showed a decrease in expression levels of RECK after transfection with pre-miR-21, and an increase of MMP9 that is regulated by RECK compared to PCa cells treated with anti-miR-21. We defined three profiles to compare the prognostic factors. The first was characterized by miR-21 and RECK underexpression (N = 25) the second was characterized by miR-21 overexpression and RECK underexpression (N = 12), and the third was characterized by miR-21 underexpression and RECK overexpression (N = 16). From men who presented the second profile (miR-21 overexpression and RECK underexpression) 91.7% were staged pT3. For the other two groups 48.0%, and 46.7% of patients were staged pT3 (p = 0.025). Conclusions: Our results demonstrate RECK as a target of miR-21. We believe that miR-21 may be important in PCa progression through its regulation of RECK, a known regulator of tumor cell invasion.

Matrix metalloproteinase-9 polymorphisms affect plasma MMP-9 levels and antihypertensive therapy responsiveness in hypertensive disorders of pregnancy

Abnormal matrix metalloproteinase (MMP)-9 levels may have a role in hypertensive disorders of pregnancy. We examined whether MMP-9 genetic polymorphisms (g.-1562C>T and g.-90(CA)(13-25)) modify plasma MMP-9 and tissue inhibitor of metalloproteinase (TIMP)-1 levels and the responses to antihypertensive therapy in 214 patients with preeclampsia (PE), 185 patients with gestational hypertension (GH) and a control group of 214 healthy pregnant (HP). Alleles for the g.-90(CA)(13-25) polymorphism were grouped L (low) (<21 CA repeats) or H (high) (>= 21 CA repeats). Plasma MMP-9 and TIMP-1 concentrations were measured by enzyme-linked immunosorbent assay. Plasma MMP-9 concentrations were not affected by genotypes or haplotypes in HP and PE groups, except for the g.-90(CA)(13-25) polymorphism: GH patients with the LH genotype for this polymorphism have higher MMP-9 levels than those with other genotypes. The T allele for the g.-1562C>T polymorphism and the H4 haplotype (combining T and H alleles) are associated with GH and lack of responsiveness to antihypertensive therapy in GH. The H2 haplotype (combining C and H alleles) was associated with lack of responsiveness to antihypertensive therapy in PE, but not in GH. In conclusion, our results show that MMP-9 genetic variants are associated with GH and suggest that MMP-9 haplotypes affect the responsiveness to antihypertensive therapy in hypertensive disorders of pregnancy. The Pharmacogenomics Journal (2012) 12, 489-498; doi: 10.1038/tpj.2011.31; published online 19 July 2011

Matrix metalloproteinase-9 genetic variations affect MMP-9 levels in obese children

Objective: Matrix metalloproteinase-9 (MMP-9) is involved in the atherosclerotic process and functional polymorphisms in the MMP-9 gene affect MMP-9 expression/activity, and are associated with cardiovascular diseases. However, no study has tested the hypothesis that functional MMP-9 polymorphisms could affect MMP-9 levels in obese children. We investigated whether three MMP-9 gene polymorphisms (C-1562T (rs3918242), 90(CA)((14-24)) (rs2234681) and Q279R (rs17576)), or haplotypes, affect MMP-9 levels in obese children. Methods: We studied 175 healthy control children and 127 obese children. Plasma MMP-9, tissue inhibitor of MMPs (TIMP)-1 and adiponectin concentrations were measured using enzyme-linked immunosorbent assay. Results: We found similar MMP-9 genotypes, allelic and haplotypes distributions in the two study groups (P > 0.05). However, we found lower plasma MMP-9 concentrations in obese subjects carrying the CC or the QQ genotypes for the C-1562T and the Q279R polymorphisms, respectively, in obese children compared with children with the other genotypes, or with non-obese children with the same genotypes (all P < 0.05). Moreover, we found lower MMP-9 levels and lower MMP-9/TIMP-1 ratios (which reflect net MMP-9 activity) in obese children carrying the H2 haplotype (which combines the C, H and Q alleles for the three polymorphisms, respectively) when compared with obese children carrying the other haplotypes, or with non-obese children carrying the same haplotype (P < 0.05). Conclusions: Our findings show that MMP-9 genotypes and haplotypes affect MMP-9 levels in obese children and adolescents, and suggest that genetic factors may modify relevant pathogenetic mechanisms involved in the development of cardiovascular complications associated with obesity in childhood. International Journal of Obesity (2012) 36, 69-75; doi:10.1038/ijo.2011.169; published online 16 August 2011

Immunohistochemical evaluation of MMP-2, MMP-9 and CD31/microvascular density in squamous cell carcinomas of the floor of the mouth

The aim of this study was to evaluate the immunoexpression of MMP-2, MMP-9 and CD31/microvascular density in squamous cell carcinomas of the floor of the mouth and to correlate the results with demographic, survival, clinical (TNM staging) and histopathological variables (tumor grade, perineural invasion, embolization and bone invasion). Data from medical records and diagnoses of 41 patients were reviewed. Histological sections were subjected to immunostaining using primary antibodies for human MMP-2, MMP-9 and CD31 and streptavidin-biotin-immunoperoxidase system. Histomorphometric analyses quantified positivity for MMPs (20 fields per slide, 100?points grade, ×200) and for CD31 (microvessels <50?µm in the area of the highest vascularization, 5 fields per slide, 100?points grade, ×400). Statistical design was composed by non-parametric Mann-Whitney U test (investigating the association between numerical variables and immunostainings), chi-square frequency test (in contingency tables), Fisher's exact test (when at least one expected frequency was less than 5 in 2×2 tables), Kaplan-Meier method (estimated probabilities of overall survival) and Iogrank test (comparison of survival curves), all with a significance level of 5%. There was a statistically significant correlation between immunostaining for MMP-2 and lymph node metastasis. Factors associated negatively with survival were N stage, histopathological grade, perineural invasion and immunostaining for MMP-9. There was no significant association between immunoexpression of CD31 and the other variables. The intensity of immunostaining for MMP-2 can be indicative of metastasis in lymph nodes and for MMP-9 of a lower probability of survival

Infiammazione e cancro: l'interazione COX-2/CA-IX promuove il potenziale invasivo e la sopravvivenza in ipossia delle cellule del cancro colon-rettale

Cyclooxygenase-2/Carbonic anhydrase-IX up-regulation promotes invasive potential and hypoxia survival in colorectal cancer cells Purpose: Cyclooxygenase-2 (COX-2) is a major mediator of inflammation, playing a pivotal role in colorectal carcinogenesis. Hypoxia is an universal hallmark of solid tumour in vivo. This investigation was prompted by the observation that in colorectal cancer cells the expression of COX-2 protein is positively correlated with that of the hypoxia survival gene Carbonic Anhydrase-IX (CA-IX). Experimental Design: Since COX-2 gene expression and activity is increased in hypoxia, and that CA-IX is expressed also in normoxia in colorectal cancer cells, we tested the hypothesis that COX-2 activity in normoxia, as well as in hypoxia may be functionally linked to that of CA-IX gene. We investigated the role of COX-2 and CA-IX in colorectal cancer cell lines. In this regard, we performed RNA interference to knockdown COX-2 gene in vitro and immunohistochemistry to evaluate the protein expression of COX-2 and CA-IX in human colon cancer tissue specimens ex vivo. Results: We found that COX-2, by PGE2 production, controls CA-IX gene expression in an ERK dependent manner. In line with this finding, we also showed that the COX-2 inhibition by a specific short harpin COX-2 RNA (shCOX-2) or by a specific drug (SC-236), down-regulated CA-IX expression in colon cancer cells. We then exposed colon cancer cells to hypoxia stimuli and found that COX-2/CA-IX interplay promoted hypoxia survival. Moreover, we also report that COX-2/CA-IX interplay triggers Matrix Metalloproteinase 2/9 (MMP-2/9) activation and enhances the invasiveness of colorectal cancer cells. Thus given our above observations, we found that CA-IX and COX-2 protein expressions correlate with more aggressive stage colorectal cancer tissues ex vivo. Conclusions: Taken together these data indicate that COX-2/CA-IX interplay promotes an aggressive phenotype (hypoxia survival and invasiveness) which can be modulated in vitro by COX-2 selective inhibition and which may play a role in determining the biological aggressiveness of colorectal tumours. Moreover, in vitro and ex vivo data also suggest that the signatures of inflammation (COX-2) and hypoxia (CA-IX) may be difficult to be disentangled in colon cancer, being both responsible for the up-regulation of the same pathways.

Molecular characterization of the immune modulatory function of matrix metalloproteinase-7, a factor in the tumour micromilieu

Matrix metalloproteinases are the components of the tumour microenvironment which play a crucial role in tumour progression. Matrix metalloproteinase-7 (MMP-7) is expressed in a variety of tumours and the expression is associated with an aggressive malignant phenotype and poor prognosis. A role for MMP-7 in the immune escape of tumours has been postulated, but the mechanisms are not clearly understood. The present study was focused on identifying physiological inactivators of MMP-7 and also to unravel the mechanisms involved in MMP-7 mediated immune escape. This study shows that human leukocyte elastase (HLE), secreted by polymorphonuclear leukocytes cleaves MMP-7 in the catalytic domain as revealed by N-terminal sequencing. Further analysis demonstrates that the activity of MMP-7 was drastically decreased after HLE treatment in a time and dose dependent manner. MMP-7 induces apoptosis resistance in tumour cells by cleaving CD95 and CD95L. The effect of HLE on MMP-7 mediated apoptosis resistance was analysed. In vitro stimulation of apoptosis by anti-Apo-1 (anti-CD95 antibody) and the chemotherapeutic drug doxorubicin is reduced by MMP-7. Also tumour specific cytotoxic T cells do not effectively kill tumour cells in the presence of MMP-7. This study revealed that HLE abrogates the negative effect of MMP-7 on apoptosis induced by CD95 stimulation, doxorubicin or cytotoxic T cells and restores apoptosis sensitivity of tumour cells. To gain insight into the possible immune modulatory functions of MMP-7, experiments were performed to identify new immune relevant substrates. The human T cell line, Jurkat, was selected for these studies. Hsc70 which is involved in uncoating of clathrin vesicles was found in the supernatants of the MMP-7 treated cells indicating a modulatory role of MMP-7 on endocytosis. Further studies demonstrated that MMP-7 leads to decreased clathrin staining in HEK293, HepG2, Jurkat, CD4+ T cells and dendritic cells. Results also show MMP-7 treatment increased surface expression of cytotoxic T lymphocyte associated protein-4 (CTLA-4) which accumulated due to inhibition of the clathrin mediated internalization in CD4+CD25+ cells.

Regulation der Phorbolester-induzierten Matrix-Metalloproteinase-9-Expression in humanen Brustkrebszelllinien durch Stickstoffmonoxid

Das Hauptziel dieser Arbeit war die Identifizierung der Regulationsebenen auf denen die TPA-induzierte Matrix-Metalloproteinase-9 (MMP-9) durch das nitrose Gas Stickstoffmonoxid (NO) in MCF-7-Zellen verändert wird. Dabei konnte sowohl mit Hilfe der Zymographie als auch mit einem MMP-9-Aktivitäts-ELISA gezeigt werden, dass die extrazellulären MMP-9-Spiegel durch die Behandlung der Zellen mit NO reduziert werden. Gleichzeitig zeigte sich auch eine durch NO bedingte Abnahme der intrazellulären MMP-9-Spiegel, wie mit Hilfe von Western-Blot-Analyse nachgewiesen werden konnte. Experimente mit dem Proteasominhibitor Lactacystin und dem Proteinsynthesehemmstoff Cycloheximid ließen darüber hinaus eine NO-bedingte Veränderung der MMP-9-Proteinstabilität ausschließen. Im Gegensatz dazu konnte mittels der metabolischen Markierung mit radioaktiv markiertem Methionin und Cystein gezeigt werden, dass die Proteinneusynthese der MMP-9 durch eine Behandlung der Zellen mit NO stark beeinträchtigt wird. In Übereinstimmung mit diesen Daten finden sich reduzierte MMP-9-mRNA-Spiegel auch in der polysomalen Zellfraktion von MCF-7-Zellen. Wie mit Hilfe des Transkriptionshemmstoffes Actinomycin D und durch Reportergenstudien mit hybriden MMP-9-Promotorkonstrukten gezeigt werden konnte, ist die NO-induzierte Reduktion der MMP-9-mRNA-Spiegel nicht auf eine Verringerung der MMP-9-mRNA-Stabilität zurückzuführen. Reportergenstudien mit einem 670bp langen Promotorfragment des 5’flankierenden Bereichs des humanen MMP-9-Gens zeigten jedoch auf, dass der hemmende Effekt des NOs zum Teil auf eine NO-vermittelte Abnahme der TPA-induzierten MMP-9-Promotoraktivität zurückgeführt werden kann. Demzufolge wurde in den nachfolgenden Experimenten nach den für die MMP-9-Expression notwendigen und von NO modulierten Transkriptionsfaktoren in MCF-7-Zellen gesucht. Anhand von Western-Blot-Analysen und Gelshiftanalysen konnte gezeigt werden, dass die Aktivität des Transkriptionsfaktors AP-1 in MCF-7-Zellen durch NO gehemmt wird, während weder die Expressionspiegel noch die Bindungsaffinität der Transkriptionsfaktoren NFκB und Sp1 durch die NO-Behandlung verändert sind. Weiterhin konnte unter Verwendung von pharmakologischen Inhibitoren der MAPK-Signalwege mit Hilfe der Western-Blot-Analyse nachgewiesen werden, dass MAPK-vermittelte Signalwege zwar für die Induktion der MMP-9-Expression essenziell sind, diese jedoch nicht von NO beeinflusst sind. Im Unterschied hierzu konnte mit Hilfe eines PKC-Aktivitätsassays gezeigt werden, dass die Gesamtaktivität von PKCs nach Behandlung von MCF-7-Zellen mit NO signifikant gehemmt ist. Zusammenfassend zeigen diese Untersuchungen, dass die NO-vermittelte Hemmung der TPA-induzierten MMP-9-Expression in MCF-7-Zellen im Wesentlichen auf eine NO-abhängige Reduktion der Protein-Kinase-C-Aktivität und einer daraus resultierenden Aktivitätshemmung des Transkriptionsfaktors AP-1 zurückgeführt werden kann.

Tenascin-C and matrix metalloproteinase-9 levels in crevicular fluid of teeth and implants

The role of and interaction between bacterial infection and biomechanical impact in the development of peri-implant inflammatory processes is not clear.

Matrix metalloproteinase-19 is a predictive marker for tumor invasiveness in patients with oropharyngeal squamous cell carcinoma

AIMS: To evaluate the expression of matrix metalloproteinase-19 (MMP-19) in oropharyngeal squamous cell carcinoma along with its association with structural features of invasiveness. To investigate whether MMP-19 expression correlates with lymphatic or systemic metastasis and prognosis in patients who have received definitive radiotherapy. METHODS AND RESULTS: The histological evaluation of the invasive front was based on Bryne's malignancy grading system. We correlated the immunohistochemical expression pattern with morphological parameters which characterize tumor invasiveness such as keratinization, nuclear polymorphism, invasion pattern, and the host inflammatory response. Local immunoreactivity for MMP-19 was positively correlated with tumor invasiveness as reflected in its structural characteristics and the degree of nuclear polymorphism, and negatively correlated with the inflammatory response of the host. No correlation existed between MMP-19 expression and clinicopathological features (TNM stage, grade of differentiation) or a patient''s outcome and prognosis. CONCLUSIONS: This latter finding probably reflects the unique change for MMPs from high immunoreactivity within healthy tissue areas and non-invasive tumor parts, through absence in the least invasive neoplastic regions, to strong re-expression at a highly invasive front of the same tumor. Our findings indicate that MMP-19 can be used as a marker for tumor invasiveness in patients with oropharyngeal squamous cell carcinoma.

Matrix metalloproteinase-9 in pneumococcal meningitis: activation via an oxidative pathway

In experimental bacterial meningitis, matrix metalloproteinases (MMPs) and reactive oxygen species (ROS) contribute to brain damage. MMP-9 increases in cerebrospinal fluid (CSF) during bacterial meningitis and is associated with the brain damage that is a consequence of the disease. This study assesses the origin of MMP-9 in bacterial meningitis and how ROS modulate its activity. Rat brain-slice cultures and rat polymorphonuclear cells (PMNs) that had been challenged with capsule-deficient heat-inactivated Streptococcus pneumoniae R6 (hiR6) released MMP-9. Coincubation with either catalase, with the myeloperoxidase inhibitor azide, or with the hypochlorous acid scavenger methionine almost completely prevented activation, but not the release, of MMP-9, in supernatants of human PMNs stimulated with hiR6. Thus, in bacterial meningitis, both brain-resident cells and invading PMNs may act as sources of MMP-9, and stimulated PMNs may activate MMP-9 via an ROS-dependent pathway. MMP-9 activation by ROS may represent a target for therapeutic intervention in bacterial meningitis.

Bovine primary chondrocyte culture in synthetic matrix metalloproteinase-sensitive poly(ethylene glycol)-based hydrogels as a scaffold for cartilage repair

A poly(ethylene glycol) (PEG)-based hydrogel was used as a scaffold for chondrocyte culture. Branched PEG-vinylsulfone macromers were end-linked with thiol-bearing matrix metalloproteinase (MMP)-sensitive peptides (GCRDGPQGIWGQDRCG) to form a three-dimensional network in situ under physiologic conditions. Both four- and eight-armed PEG macromer building blocks were examined. Increasing the number of PEG arms increased the elastic modulus of the hydrogels from 4.5 to 13.5 kPa. PEG-dithiol was used to prepare hydrogels that were not sensitive to degradation by cell-derived MMPs. Primary bovine calf chondrocytes were cultured in both MMP-sensitive and MMP-insensitive hydrogels, formed from either four- or eight-armed PEG. Most (>90%) of the cells inside the gels were viable after 1 month of culture and formed cell clusters. Gel matrices with lower elastic modulus and sensitivity to MMP-based matrix remodeling demonstrated larger clusters and more diffuse, less cell surface-constrained cell-derived matrix in the chondron, as determined by light and electron microscopy. Gene expression experiments by real-time RT-PCR showed that the expression of type II collagen and aggrecan was increased in the MMP-sensitive hydrogels, whereas the expression level of MMP-13 was increased in the MMP-insensitive hydrogels. These results indicate that cellular activity can be modulated by the composition of the hydrogel. This study represents one of the first examples of chondrocyte culture in a bioactive synthetic material that can be remodeled by cellular protease activity.

Effects of stimulus with proinflammatory mediators on nitric oxide production and matrix metalloproteinase activity in explants of cranial cruciate ligaments obtained from dogs

OBJECTIVE To evaluate the origin and degree of activity of nitric oxide (NO) and matrix metalloproteinase (MMP) in explants of cranial cruciate ligaments (CCLs) obtained from dogs and cultured with and without inflammatory activators. SAMPLE POPULATION Tissue specimens obtained from 7 healthy adult Beagles that were (mean +/- SD) 4.5 +/- 0.5 years old and weighed 12.5 +/- 0.8 kg. PROCEDURE The CCLs were harvested immediately after dogs were euthanatized, and specimens were submitted for explant culture. Cultures were stimulated by incubation with a combination of interleukin-1, tumor necrosis factor-alpha, and lipopolysaccharide, or they were not stimulated. Culture supernatants were examined for production of NO nitrite-nitrate metabolites (NOts) and activity of MMP Cultured specimens were evaluated by use of immunohistochemical analysis to detect activity of inducible NO synthase (iNOS). RESULTS All ligament explants produced measurable amounts of NOts. Stimulated cultures produced significantly more NOts after incubation for 24 and 48 hours, compared with nonstimulated cultures. Production of MMP in supernatants after incubation for 48 hours was significantly higher in stimulated cultures than in nonstimulated cultures. Cells with positive staining for iNOS were detected on all slides. Positively stained cells were predominantly chondroid metaplastic. There was a significant difference in intensity of cell staining between stimulated and non-stimulated cultures. CONCLUSIONS AND CLINICAL RELEVANCE Explant cultures of intact CCLs obtained from dogs produce iNOS-induced NO. Stimulation of chondroid metaplastic cells in CCL of dogs by use of inflammatory activators can increase production of iNOS, NOts, and MMP.

Circulating matrix metalloproteinase 9 levels in relation to sampling methods, femoral and carotid atherosclerosis.

OBJECTIVES To examine whether circulating levels of matrix metalloproteinase 9 (MMP-9) were associated with ultrasound-assessed intima-media thickness (IMT) and echolucent plaques in the carotid and femoral arteries. To examine preanalytical sources of variability in MMP-9 concentrations related to sampling procedures. SUBJECTS AND DESIGN Plasma and serum MMP-9 levels were compared with ultrasound assessed measures of femoral and carotid atherosclerosis, in a cross-sectional study of 61-year-old men (n = 473). Preanalytical sources of variability in MMP-9 levels were examined in 10 healthy subjects. Main outcome measures were circulating levels of MMP-9 in serum and plasma, IMT of the carotid and femoral arteries, and plaque status based on size and echolucency. SETTING Research unit at university hospital. RESULTS Plasma concentrations of total and active MMP-9 were associated with femoral artery IMT independently of traditional cardiovascular risk factors, and were higher in subjects with moderate to large femoral plaques. Plasma MMP-9 concentration was higher in men with echolucent femoral plaques (P = 0.006) compared with subjects without femoral plaques. No similar associations were found for carotid plaques. MMP-9 concentrations were higher in serum than in plasma, and higher when sampling was performed with Vacutainer than with syringe. MMP-9 levels in serum were more strongly associated with peripheral neutrophil count compared with MMP-9 levels in plasma. CONCLUSIONS Plasma MMP-9 levels were associated with atherosclerosis in the femoral artery, and total MMP-9 concentration was higher in men with echolucent femoral plaques. The choice of sample material and sampling method affect the measurements of circulating MMP-9 levels.

Functional studies of insulin-like growth factor binding protein 2 pathway in glioma progression

Comparison of gene expressing profiles between gliomas with different grades revealed frequent overexpression of insulin-like growth factor binding protein 2 (IGFBP2) in glioblastomas (GBM), in which uncontrolled cell proliferation, angiogenesis, invasion and anti-apoptosis are hallmarks. Using the glia-specific gene transfer transgenic mouse and the stable LN229(BP2) GBM cell lines, we found that IGFBP2 by itself cannot transform cells in vitro and in vivo. IGFBP2 had growth inhibitory effects on mouse primary neural progenitors, but overexpression of IGFBP2 had no effect on GBM cells. ^ Although IGFBP2 does not initiate gliomagenesis, using tissue array technology, we observed strong correlation between IGFBP2 overexpression and VEGF up-regulation in human diffuse gliomas. Furthermore, overexpression of IGFBP2 in GBM cells not only enhanced VEGF expression but also increased the malignant potential of U87 MG cells in our angiogenesis xenograft animal model. ^ In parallel to these studies, using established stable SNB19 GBM cells that overexpress IGFBP2, we found that IGFBP2 significantly increased invasion by induction of matrix metalloproteinase-2 (MMP-2) as well as other invasion related genes, providing evidence that IGFBP2 contributes to glioma progression in part by enhancing MMP-2 gene transcription and in turn tumor cell invasion. ^ Finally, we found that primary filial cells infected with an anti-sense IGFBP2 construct have markedly increased sensitivity to γ irradiation and reduced Akt activation. On the other hand, SNB19(BP2) stable lines have consistently increased levels of Akt and NFkB activation, suggesting that one possible mechanism for anti-apoptosic function of IGFBP2 is through the activation of Akt and NFkB. Beside this, what is especially interesting is the finding that Akt protein was cleaved and inactivated during apoptosis by caspases, and IGFBP2 can prevent Akt cleavage, revealing another possible mechanism through it IGFBP2 exhibit strong antiapoptotic effects. Our data showed that IGFBP2 is a specific substrate for caspase-3, raising the possibility that IGFBP2 may inhibit apoptosis by a suicide mechanism. ^ In summary, using cellular, genomics, and molecular approaches, this thesis documented the potential roles of IGFBP2 in glioma progression. Our findings shed light on an important biological aspect of glioma progression and may provide new insights useful for the design of novel mechanism-based therapies for GBM. ^