MT1-MMP Expression Research Articles

SLFN5 suppresses cancer cell migration and invasion by inhibiting MT1-MMP expression via AKT/GSK-3β/β-catenin pathway

Human SLFN5 inhibits invasions of IFNα-sensitive renal clear-cell carcinoma and melanoma cells. However, whether this inhibition is confined to these IFNα-sensitive cancers is unclear. Here we show that SLFN5 expressions on both mRNA and protein levels are significantly higher in non/low-invasive cancer cell lines (breast cancer cell line MCF7, colorectal cancer cell line HCT116 and lung cancer cell line A549) than in highly-invasive cancer cell lines (fibrosarcoma cell line HT1080 and renal clear cell cancer cell line 786-0). SLFN5 knockdown in non/low-invasive cancer cell lines enhanced MT1-MMP expression and increased migration and invasion in vitro, and in vivo. Furthermore, SLFN5 overexpression in HT1080 and 786-0 inhibited MT1-MMP expression and repressed migration and invasion. MT1-MMP is instrumental in SLFN5-controlled inhibition of cancer cell migration and invasion, as shown by MT1-MMP-knockdown and -overexpression analyses. SLFN5 knockdown activated AKT/GSK-3β/β-catenin pathway by promotion AKT phosphorylation and subsequent GSK-3β phosphorylation, further β-catenin translocation into nucleus as un-phosphorylated protein at Ser33, 37 and 45 and Thr41 sites. This is the first study to report that SLFN5 inhibits cancer migration and invasiveness in several common cancer cell lines by repressing MT1-MMP expression via the AKT/GSK-3β/β-catenin signalling pathway, suggesting that SLFN5 plays wide inhibitory roles in various cancers.

Bicyclic Peptides as a New Modality for Imaging and Targeting of Proteins Overexpressed by Tumors.

Molecular imaging of cancers using probes specific for tumor-associated target proteins offers a powerful solution for providing information regarding selection of targeted therapy, patient stratification, and response to therapy. Here we demonstrate the power of bicyclic peptides as targeting probes, exemplified with the tumor-overexpressed matrix metalloproteinase MT1-MMP as a target. A bicyclic peptide with subnanomolar affinity towards MT1-MMP was identified, and its radioconjugate showed selective tumor uptake in an HT1080 xenograft mouse model. Proteolytic stabilization of the peptide by chemical modification significantly enhanced the in vivo tumor signal [from 2.5%ID/g to 12%ID/g at 1 hour post injection (p.i.)]. Studies using mouse xenograft models with different cell lines show a robust correlation between tumor signals and in vivo MT1-MMP expression levels. Fatty acid modification of the bicyclic peptide extended its circulating half-life, resulting in increased tumor signals (36%ID/g at 6 hours p.i.). Comparative work with an equipotent radiolabeled MT1-MMP targeting antibody demonstrated starkly differential biodistribution and tumor accumulation properties, with the tumor signal slowly increasing to 6.2%ID/g within 48 hours. The rapid tumor penetration characteristics of bicyclic peptides, coupled with high potency and chemical versatility, thus offer high-contrast imaging probes for clinical diagnostics with compelling additional potential in targeted therapy.Significance: This work demonstrates the potential of bicyclic peptides as a platform for the development of high-contrast imaging probes for potential use in clinical cancer diagnostics and molecularly targeted therapeutics.

Changes of lymphatic vessel density in lung adenocarcinoma in situ, minimally invasive adenocarcinoma, and invasive adenocarcinoma and the regulatory factors

To analyze the changes in tumor lymphatic vessel density (LVD) in patients with lung adenocarcinoma in situ (AIS), minimally invasive adenocarcinoma (MIA), and invasive adenocarcinoma (IA) and explore the regulatory factors of LVD. Complete clinicopathological data were collected form a total of 301 patients with lung adenocarcinoma, including 28 (9.3%) with AIS, 86 (28.6%) with MIA, and 187 (62.1%) with IA. The LVD of all the adenocarcinomas were calculated after D2-40 immunohistochemical staining, and MT1-MMP and VEGF-C expression levels were also evaluated. The differences in LVD among the groups and the correlations of tumor LVD with the expressions of MT1-MMP and VEGF-C and the clinicopathological factors were analyzed. The LVD differed significantly among AIS, MIA, and IA groups (P= 0.000). The LVDs was significantly correlated with the level of VEGF-C protein expression (r=0.917, P=0.009), tumor size (r= 0.686, P=0.017), lymph node metastasis (r=0.739, P=0.000), and clinical stage (r=0.874, P=0.012) of the patients. Tumor lymphangiogenesis plays an important role in lung adenocarcinoma progression, and VEGF-C may promote this process.

The membrane tethered matrix metalloproteinase MT1-MMP triggers an outside-in DNA damage response that impacts chemo- and radiotherapy responses of breast cancer

Breast cancer is the second leading cause of death among women in the US. Targeted therapies exist, however resistance is common and patients resort to chemotherapy. Chemotherapy is also a main treatment for triple negative breast cancer (TNBC) patients; while radiation is delivered to patients with advanced disease to counteract metastasis. Yet, resistance to both chemo- and radiotherapy is still frequent, highlighting a need to provide novel sensitizers. We discovered that MT1-MMP modulates DNA damage responses (DDR) in breast cancer. MT1-MMP expression inversely correlates to chemotherapy response of breast cancer patients. Inhibition of MT1-MMP sensitizes TNBC cells to IR and doxorubicin in vitro, and in vivo in an orthotopic breast cancer model. Specifically, depletion of MT1-MMP causes stalling of replication forks and Double Strand Breaks (DBSs), leading to increased sensitivity to additional genotoxic stresses. These effects are mediated by integrinβ1, as a constitutive active integrinβ1 reverts replication defects and protects cells depleted of MT1-MMP from IR and chemotherapy. These data highlight a novel DNA damage response triggered by MT1-MMP-integrinβ1 and provide a new point of therapeutic targeting that may improve breast cancer patient outcomes.

Pancreatic tumor cell metastasis is restricted by MT1-MMP binding protein MTCBP-1

The process by which tumor cells mechanically invade through surrounding stroma into peripheral tissues is an essential component of metastatic dissemination. The directed recruitment of the metalloproteinase MT1-MMP to invadopodia plays a critical role in this invasive process. Here, we provide mechanistic insight into MT1-MMP cytoplasmic tail binding protein 1 (MTCBP-1) with respect to invadopodia formation, matrix remodeling, and invasion by pancreatic tumor cells. MTCBP-1 localizes to invadopodia and interacts with MT1-MMP. We find that this interaction displaces MT1-MMP from invadopodia, thereby attenuating their number and function and reducing the capacity of tumor cells to degrade matrix. Further, we observe an inverse correlation between MTCBP-1 and MT1-MMP expression both in cultured cell lines and human pancreatic tumors. Consistently, MTCBP-1-expressing cells show decreased ability to invade in vitro and metastasize in vivo. These findings implicate MTCBP-1 as an inhibitor of the metastatic process.

Involvement of Catechols in Acteoside in the Activation of Promatrix Metalloproteinase-2 and Membrane Type-1-Matrix Metalloproteinase Expression via a Phosphatidylinositol-3-Kinase Pathway in Human Dermal Fibroblasts.

Granulation tissue formation during skin wound healing requires the migration and proliferation of dermal fibroblasts in the wound site, where a subsequent remodeling of extracellular matrices (ECM) occurs. An abnormality of ECM remodeling within the healing wound leads to fibrosis and a contracted scar. To evaluate whether acteoside, a phenylethanoid glycoside isolated from the leaves of Rehmannia glutinosa LIBOSCH., exhibits wound-healing actions, we examined the effect of acteoside on the expression of matrix metalloproteinases (MMPs) in normal human dermal fibroblasts (NHDF). Acteoside dose- and time-dependently augmented the activation of the precursor of MMP-2 (proMMP-2/progelatinase A) in untreated- and interleukin-1β-treated NHDF, while the alteration of the MMP-2 gene expression was negligible. The acteoside-induced proMMP-2 activation was associated with the augmented membrane-type 1 MMP (MT1-MMP) expression in the NHDF. In addition, the proMMP-2 activation was enhanced by two aglycones in acteoside: caffeic acid and 3,4-dihydroxyphenylethanol, which consist of catechol. However, there was no change in the proMMP-2 activation in other catechol derivatives: homovanillyl alcohol- and homovanillic acid-treated NHDF, indicating that catechols in acteoside were requisite for the regulation of the MMP activation and expression in NHDF. Furthermore, the proMMP-2 activation by acteoside was selectively inhibited by LY294002, a potent phosphatidylinositol-3-kinase (PI3K) inhibitor. These results provide novel evidence that acteoside augments proMMP-2 activation along with an increase in MT1-MMP expression through a PI3K signal pathway in NHDF. Thus, acteoside is likely to be an attractive candidate that facilitates ECM remodeling in the skin wound repair process.

An IL13R\u03b12 peptide exhibits therapeutic activity against metastatic colorectal cancer

BackgroundInterleukin 13 receptor α2 (IL13Rα2) is overexpressed in metastatic colorectal cancer. Here, we have developed novel strategies to block IL-13 binding to IL13Rα2 in order to reduce metastatic spread.MethodsSynthetic IL13Rα2 D1 peptide (GSETWKTIITKN) was tested for the inhibition of IL-13 binding to IL13Rα2 using ELISA and different cellular assays. Peptide blocking effects on different cell signalling mediators were determined by western blot. An enantiomer version of the peptide (D-D1) was prepared to avoid proteolytic digestion. Nude mice were used for tumour growth and survival analysis after treatment with IL13Rα2 peptides.ResultsIL13Rα2 D1 peptide inhibited migration, invasion, and proliferation in metastatic colorectal and glioblastoma cancer cells treated with IL-13. Residues 82K, 83T, 85I and 86T were essential for blocking IL-13. IL13Rα2 peptide abolished ligand-mediated receptor internalisation and degradation, and substantially decreased IL-13 signalling capacity through IL13Rα2 to activate the FAK, PI3K/AKT and Src pathways as well as MT1-MMP expression. In addition, D1 significantly inhibited IL-13-mediated STAT6 activation through IL13Rα1. Nude mice treated with the enantiomer D-D1 peptide showed a remarkable survival increase.ConclusionsWe propose that the D-D1 peptide from IL13Rα2 represents a promising therapeutic agent to inhibit metastatic progression in colorectal cancer and, likely, other solid tumours.

Correction: Mechanosensitive caveolin-1 activation-induced PI3K/Akt/mTOR signaling pathway promotes breast cancer motility, invadopodia formation and metastasis in vivo.

[This corrects the article DOI: 10.18632/oncotarget.7583.].

Enolase-phosphatase 1 as a novel potential malignant glioma indicator promotes cell proliferation and migration.

Enolase-phosphatase1 (ENOPH1), is an enzyme that is involved in polyamine biosynthesis and is associated with stress responses. However, little is known about its role in the pathophysiology of glioma. In the present study, we examined the expression and function of ENOPH1 in human glioma tissues and cell lines. Western blot, qPCR and immunohistochemistry analysis were performed to investigate the expression of the ENOPH1 protein in glioma tissues in 86patients. The 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide(MTT), wound healing and cell cycle assays were implemented to identify cell growth and cell migration in U87 and U251 glioma cells. The results revealed that compared with normal brain tissues, the level of ENOPH1 was markedly increased in glioma tissues. In addition, we observed that the glioma pathological grade was positively associated with the expression level of ENOPH1. Knockdown of ENOPH1 expression with siRNA markedly reduced cell proliferation, and significantly decreased cell migration. Notably, knockdown of ENOPH1 promoted its downstream protein, aci-reductone dioxygenase1(ADI1), to shift from the nucleus to the cytoplasm of U251 glioma cells, while MT1-MMP expression was significantly downregulated compared with the control group. Collectively, our data demonstrated that the knockdown of ENOPH1 suppressed cell growth and migration, which may be associated with ADI1 translocation and MT1-MMP downregulation in glioma cells. Thus, ENOPH1 could serve as an underlying therapeutic target of glioma.

Effects of treadmill exercise on cerebral angiogenesis and MT1-MMP expression after cerebral ischemia in rats.

IntroductionDespite the increased understanding of treadmill training on angiogenesis of stroke patients, its mechanism is not clearly known. The metalloproteinase membrane type 1‐metalloprotease (MT1‐MMP) promotes the regeneration of the peripheral vessels but seldom research on the regeneration of cerebral blood vessels. This study was designed to investigate the effects of treadmill exercise on angiogenesis and MT1‐MMP expression after cerebral ischemia in rats.MethodsThe adult male Sprague Dawley(SD) rats were randomly divided into three groups: sham operation group, the middle cerebral artery occlusion group(MCAO) and middle cerebral artery occlusion group(MCAO)+exercise group. In 4d, 7d or 14d after MCAO, respectively, the rats’ neurological function was evaluated by the modified neurologic severity scores (mNSS); the microvessel numbers in areas surrounding cerebral ischemia were counted with Microvessel Density(MVD)analysis; the levels of MT1‐MMP and reversion‐inducing cysteine‐rich protein with Kazalmotifs (RECK) were detected by Western‐blot and immunohistochemical method.ResultsCompared with MCAO group, the number of capillaries and the level of MT1‐MMP expression around the area of cerebral ischemia were significantly increased in each exercise group (p < 0.05), while the level of RECK expression and the scores of mNSS in each exercise group were significantly decreased (p < 0.05).ConclusionThis study suggested that treadmill exercise training can significantly promote angiogenesis and improve neurological function after cerebral ischemia. Its mechanism may be related to the upgraduation of the MT1‐MMP expression in brain microvessels surrounding area of the ischemic rat.

Optimization of a MT1-MMP-targeting Peptide and Its Application in Near-infrared Fluorescence Tumor Imaging

Membrane type 1 metalloproteinase (MT1-MMP) is an important regulator of cancer invasion, growth and angiogenesis, thus making it an attractive target for cancer imaging and therapy. A non-substrate peptide (MT1-AF7p) that bonded to the “MT-Loop” region of MT1-MMP was identified by using a phage-displayed peptide library and was used to image the MT1-MMP expression in vivo through optical imaging. However, the substrate in the screening did not have a 3D structure, thus resulting in a loose bonding of MT1-AF7p. To simulate the real conformation of the “MT-Loop” and improve the performance of MT1-AF7p, molecular simulations were performed, because this strategy provides multiple methods for predicting the conformation and interaction of proteinase in 3D. In view of the binding site of the receptor–ligand interactions, histidine 4 was selected for mutation to achieve an increased affinity effect. The optimized peptides were further identified and conformed by atomic force microscopy, isothermal titration calorimetry, cell fluorescence imaging in vitro, and near-infrared fluorescence tumor optical imaging in vivo. The results revealed that the optimized peptide with a mutation of histidine 4 to arginine has the highest affinity and specificity, and exhibited an increased fluorescence intensity in the tumor site in optical imaging.

Age-related modifications of type I collagen impair DDR1-induced apoptosis in non-invasive breast carcinoma cells

ABSTRACTType I collagen and DDR1 axis has been described to decrease cell proliferation and to initiate apoptosis in non-invasive breast carcinoma in three-dimensional cell culture matrices. Moreover, MT1-MMP down-regulates these effects. Here, we address the effect of type I collagen aging and MT1-MMP expression on cell proliferation suppression and induced-apoptosis in non-invasive MCF-7 and ZR-75-1 breast carcinoma. We provide evidence for a decrease in cell growth and an increase in apoptosis in the presence of adult collagen when compared to old collagen. This effect involves a differential activation of DDR1, as evidenced by a higher DDR1 phosphorylation level in adult collagen. In adult collagen, inhibition of DDR1 expression and kinase function induced an increase in cell growth to a level similar to that observed in old collagen. The impact of aging on the sensitivity of collagen to MT1-MMP has been reported recently. We used the MT1-MMP expression strategy to verify whether, by degrading adult type I collagen, it could lead to the same phenotype observed in old collagen 3D matrix. MT1-MMP overexpression abrogated the proliferation suppression and induced-apoptosis effects only in the presence of adult collagen. This suggests that differential collagen degradation by MT1-MMP induced a structural disorganization of adult collagen and inhibits DDR1 activation. This could in turn impair DDR1-induced cell growth suppression and apoptosis. Taken together, our data suggest that modifications of collagen structural organization, due to aging, contribute to the loss of the growth suppression and induced apoptosis effect of collagen in luminal breast carcinoma. MT1-MMP-dependent degradation and aging of collagen have no additive effects on these processes.

Serglycin promotes breast cancer cell aggressiveness: Induction of epithelial to mesenchymal transition, proteolytic activity and IL-8 signaling

Serglycin is an intracellular proteoglycan that is expressed and constitutively secreted by numerous malignant cells, especially prominent in the highly-invasive, triple-negative MDA-MB-231 breast carcinoma cells. Notably, de novo expression of serglycin in low aggressive estrogen receptor α (ERα)-positive MCF7 breast cancer cells promotes an aggressive phenotype. In this study, we discovered that serglycin promoted epithelial to mesenchymal transition (EMT) in MCF7 cells as shown by increased expression of mesenchymal markers vimentin, fibronectin and EMT-related transcription factor Snail2. These phenotypic traits were also associated with the development of drug resistance toward various chemotherapy agents and induction of their proteolytic potential as shown by the increased expression of matrix metalloproteinases, including MMP-1, MMP-2, MMP-9, MT1-MMP and up-regulation of urokinase-type plasminogen activator. Knockdown of serglycin markedly reduced the expression of these proteolytic enzymes in MDA-MB-231 cells. In addition, serglycin expression was closely linked to a pro-inflammatory gene signature including the chemokine IL-8 in ERα-negative breast cancer cells and tumors. Notably, serglycin regulated the secretion of IL-8 in breast cancer cells independently of their ERα status and promoted their proliferation, migration and invasion by triggering IL-8/CXCR2 downstream signaling cascades including PI3K, Src and Rac activation. Thus, serglycin promotes the establishment of a pro-inflammatory milieu in breast cancer cells that evokes an invasive mesenchymal phenotype via autocrine activation of IL-8/CXCR2 signaling axis.

Effects of black chokeberry extracts on metastasis and cell-cycle arrest in SK-Hep1 human liver cancer cell line

Objective: To determine the anti-cancer properties of black chokeberry extract on the SK- Hep1 human liver cancer cell line. Methods: MTT cell proliferation assay, wound migration, invasion, zymography and cell cycle were determined after black chokeberry fruit extract treatment. We also measured MMP-2/-9 and MT-1 MMP expression with protein and gene expression levels. Results: We detected four anthocyanins and three phenolic compounds in the black chokeberry by HPLC analysis. Cancer cell growth was inhibited in proportion to the concentration of black chokeberry extracts. In the adhesion test, 100 and 200 μg/mL of black chokeberry extracts decreased the adhesion rate of cancer cells to 87.6% and 75.3%, respectively, when the control group was 100.0%. The 200 μg/mL of black chokeberry extract reduced the MMP-2 and MMP-9 expressions up to 96.8%and 11.3%, respectively. Conclusions: Based on our results, in the SK-Hep1 liver cancer cells, the black chokeberry extract inhibits cancer cell proliferation, adhesion, and migration, ultimately inhibiting cancer metastasis.

Anti-cancer and anti-inflammatory activities of aronia (Aronia melanocarpa) leaves

Objective: To determine the anti-cancer effect of aronia leaf extract on SK-Hep1 cells using migration, metallo metrix proteinase-2/-9 (MMP-2/-9) and MT-1 MMP expression and to evaluate the anti-inflammatory activities of the leaf extract. Methods: The effect of aronia leaf extract on cancer prevention was investigated. SK-Hep1 human liver cancer cell line was treated with aronia leaf extract at various concentractions. MTT assay was used to measure cancer cell growth inhibition, and wound migration assay was used for metastasis determination. The expression of MMP-2/-9 was measured at the protein level using zymography and the expression of MMP-2/-9 and MT-1 MMP was examined at the gene level by RT-PCR. Raw 264.7 macrophage cells were stimulated with lipopolysaccharides to induce inflammation, and then the inhibition of inflammation was evaluated by treatment of aronia leaf extract. Expressions of interleukin-6, tumor factor-α, and nitric oxide (NO) were also determined. Results: SK-Hep1 cell growth was inhibited in proportion to the concentration of aronia leaf extract. In migration assay, aronia leaf extract showed 61.3%-96.3% wound size inhibtion after treating 50-200 μg/mL of aronia leaf extract for 24 h. At the protein level, the expression of MMP-2 and MMP-9 decreased as the concentration of aronia leaf extract treated with SK-Hep1 cells increased. In addition, the same pattern as in the protein was also observed in the mRNA levels. The expressions of MMP-2 and MMP-9 protein were inhibited by 92.2% and 53.8%, respectively after treatment with 200 μg/mL aronia leaf extract. In addition, Raw 264.7 cells treated with aronia leaf extract did not affect cell survival. There was dose dependent inhibition of interleukine-6, tumor necrosis factor-α and nitric oxide after treating aronia leaf extract in lipopolysaccharides-treated Raw 264.7 cell. Conclusions: The results show that aronia leaf has anticancer and and antimetastatic properties in SK-Hep1 and Raw 264.7 cells.

TGF-β–induced intracellular PAI-1 is responsible for retaining hematopoietic stem cells in the niche

AbstractHematopoietic stem and progenitor cells (HSPCs) reside in the supportive stromal niche in bone marrow (BM); when needed, however, they are rapidly mobilized into the circulation, suggesting that HSPCs are intrinsically highly motile but usually stay in the niche. We questioned what determines the motility of HSPCs. Here, we show that transforming growth factor (TGF)-β–induced intracellular plasminogen activator inhibitor (PAI)-1 activation is responsible for keeping HSPCs in the BM niche. We found that the expression of PAI-1, a downstream target of TGF-β signaling, was selectively augmented in niche-residing HSPCs. Functional inhibition of the TGF-β−PAI-1 signal increased MT1-MMP–dependent cellular motility, causing a detachment of HSPCs from the TGF-β–expressing niche cells, such as megakaryocytes. Furthermore, consistently high motility in PAI-1–deficient HSPCs was demonstrated by both a transwell migration assay and reciprocal transplantation experiments, indicating that intracellular, not extracellular, PAI-1 suppresses the motility of HSPCs, thereby causing them to stay in the niche. Mechanistically, intracellular PAI-1 inhibited the proteolytic activity of proprotein convertase Furin, diminishing MT1-MMP activity. This reduced expression of MT1-MMP in turn affected the expression levels of several adhesion/deadhesion molecules for determination of HSPC localization, such as CD44, VLA-4, and CXCR4, which then promoted the retention of HSPCs in the niche. Our findings open up a new field for the study of intracellular proteolysis as a regulatory mechanism of stem cell fate, which has the potential to improve clinical HSPC mobilization and transplantation protocols.

Effect of gestational age on migration ability of the human umbilical cord vein mesenchymal stem cells

PurposeMigration ability of mesenchymal stem cells (MSCs) towards chemotactic mediators is a determinant factor in cell therapy. MSCs derived from different sources show different properties. Here we compared the migration ability of the term and the pre-term human umbilical cord vein MSCs (hUCV-MSCs). Materials/MethodsMSCs were isolated from term and pre-term umbilical cord vein, and cultured to passage 3–4. Migration rate of both groups was assessed in the presence of 10% FBS using chemotaxis assay. Surface expression of CXCR4 was measured by flow cytometery. The relative gene expression of CXCR4, IGF1-R, PDGFRα, MMP-2, MMP-9, MT1-MMP and TIMP-2 were evaluated using real time PCR. ResultsThe isolation rate of the pre-term hUCV-MSCs was higher than the term hUCV-MSCs. Phenotype characteristics and differentiation ability of the term and pre-term hUCV-MSCs were not different. The migration rate of the pre-term hUCV-MSCs was more than the term hUCV-MSCs. Gene and surface expressions of the CXCR4 were both significantly higher in the pre-term hUCV-MSCs (P≤0.05). The mRNA levels of PDGFRα, MMP-2, MMP-9, MT1-MMP and TIMP-2 showed no significant difference between the two groups. ConclusionOur results showed that the gestational age can affect the migration ability of the hUCV-MSCs.

Abstract 969: Expression of membrane-type matrix metalloproteinases (MT-MMPS) in head and neck squamous cell carcinomas, a target for prodrug development

Abstract Introduction: Head and Neck Squamous Cell Carcinomas (HNSCC), a group of highly aggressive heterogeneous epithelial malignancies, are considered the fifth most common cancer with the seventh highest cancer mortality. Despite advances in treatment, low five-year survival rates of around 30% still remain. Several studies have implicated the actions of matrix metalloproteinases (MMPs) in HNSCC progression. Their role in mediating extracellular matrix remodeling is paramount to tumour progression, as they facilitate invasion, angiogenesis and metastasis. In contrast, expression of active MMPs in normal tissues is largely absent. MT1-MMP (MMP14) expression is known to correlate with poor clinical response in several tumour types, but little is known about the expression of other MT-MMPs in HNSCC. We have assessed the protein expression of the entire MT-MMP complement in matched tumour and normal tissues of clinical HNSCC cases by immunohistochemistry, supported by Western Blot and gene expression data and will ultimately demonstrate translation of protein expression into MT-MMP-specific proteolytic activity. Differential expression would support the development of prodrugs specifically activated in the tumour by MMPs. Methods: 32 clinical cases (matched normal &amp; tumour tissues) were assayed for gene expression of the 6 members of the MT-MMP family (MMP14,15,16,17,24,25). Expression profiling was carried out using quantitative real-time reverse transcription-PCR analysis. Analysis of protein expression used IHC on fixed sections used with monoclonal antibodies specific for MT1 to MT6 MMP and Western blot analysis with monoclonal antibodies optimized for western blotting. Results: The protein expression of all six MT-MMPs has been characterised in clinical HNSCC samples and related to matched normal tissue controls. A differential in gene and protein expression levels exists between the MT-MMP profiles across the normal and cancer tissues examined. MT1-, MT3- and MT6-MMP in particular were shown to be highly overexpressed at both gene and protein level in the majority of tumours. MT2, MT4 and MT5-MMP expression was low or undetectable in all normal tissue and low in tumour tissue Conclusion: The existence and demonstration of differential MT-MMP protein expression in HNSCC relative to normal tissues is a valuable tool for prodrug development. MT1-, MT3- and MT6-MMP are highly expressed in the majority of tumour samples compared to matched normal control tissue. However, further work to elucidate the proteolytic activity of the expressed proteins and therefore the proteolytic capacity of tumours is needed to determine the suitability of HNSCC for prodrug therapy. Citation Format: Rene Ankrah, Steve D. Shnyder, James A. McCaul, Phil A. Batman, Robert Falconer, Paul M. Loadman. Expression of membrane-type matrix metalloproteinases (MT-MMPS) in head and neck squamous cell carcinomas, a target for prodrug development [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 969. doi:10.1158/1538-7445.AM2017-969

EGFR-induced phosphorylation of type Iγ phosphatidylinositol phosphate kinase promotes pancreatic cancer progression.

Pancreatic cancer is one of the deadliest malignancies and effective treatment has always been lacking. In current study, we investigated how the type Iγ phosphatidylinositol phosphate kinase (PIPKIγ) participates in the progression of pancreatic ductal adenocarcinoma (PDAC) for novel therapeutic potentials against this lethal disease. We found that PIPKIγ is up-regulated in all tested PDAC cell lines. The growth factor (including EGFR)-induced tyrosine phosphorylation of PIPKIγ is significantly elevated in in situ and metastatic PDAC tissues. Loss of PIPKIγ inhibits the aggressiveness of PDAC cells by restraining the activities of AKT and STAT3, as well as MT1-MMP expression. Therefore when planted into the pancreas of nude mice, PIPKIγ-depleted PDAC cells exhibits substantially repressed tumor growth and metastasis comparing to control PDAC cells. Results from further studies showed that the phosphorylation-deficient PIPKIγ mutant, unlike its wild-type counterpart, cannot rescue PDAC progression inhibited by PIPKIγ depletion. These findings indicate that PIPKIγ, functioning downstream of EGFR signaling, is critical to the progression of PDAC, and suggest that PIPKIγ is potentially a valuable therapeutic target for PDAC treatment.

Curcumin inhibits the survival and metastasis of prostate cancer cells via the Notch-1 signaling pathway.

Prostate cancer is one of the most common malignancies in men, and it urgently demands precise interventions that target the signaling pathways implicated in its initiation, progression, and metastasis. The Notch-1 signaling pathway is closely associated with the pathophysiology of prostate cancer. This study investigated the antitumor effects and mechanisms of curcumin, which is a well-known natural compound from curcuminoids, in prostate cancer cells. Viability, proliferation, and migration were analyzed in two prostate cancer cell lines, DU145 and PC3, after curcumin treatment. Whether the Notch-1 signaling pathway is involved in the antitumor effects of curcumin was examined. Curcumin inhibited the survival and proliferation of PC3 and DU145 cells in a dose- and time-dependent manner and inhibited DU145 migration. Curcumin did not affect the expression of Notch-1 or its active product NICD, but it did inhibit the expression of MT1-MMP and MMP2 proteins in DU145 cells. We found that curcumin inhibited the DNA-binding ability of NICD in DU145 cells. In conclusion, curcumin inhibited the survival and metastasis of prostate cancer cells via the Notch-1 signaling pathway.