Matrix metalloproteinases and matrix metalloproteinase inhibitors in lung cancer

Lung and blood perioperative metalloproteinases in patients undergoing oncologic lung surgery: Prognostic implications

BACKGROUND

Metalloproteinases (MMPs) have been reported to be related to oncologic outcomes. The main goal of the study was to study the relationship between these proteins and the long-term prognosis of patients undergoing oncologic lung resection surgery.

METHODS

This was a substudy of the phase IV randomized control trial (NCT02168751). We analyzed MMP-2, -3, -7, and -9 in blood samples and bronchoalveolar lavage (LBA) and the relationship between MMPs and long postoperative outcomes (survival and disease-free time of oncologic recurrence).

RESULTS

Survival was longer in patients who had lower MMP-2 levels than those with higher MMP-2 in blood samples taken 6 h after surgery (6.8 vs. 5.22 years; p = 0.012) and MMP-3 (6.82 vs. 5.35 years; p = 0.03). In contrast, survival was longer when MMP-3 levels were higher in LBA from oncologic lung patients than those with lower MMP-3 (7.96 vs. 6.02 years; p = 0.005). Recurrence-free time was longer in patients who had lower MMP-3 levels in blood samples versus higher (5.97 vs. 4.23 years; p = 0.034) as well as lower MMP-7 (5.96 vs. 4.5 years; p = 0.041) or lower MMP-9 in LBA samples (6.21 vs. 4.18 years; p = 0.012).

CONCLUSION

MMPs were monitored during the perioperative period of oncologic lung resection surgery. These biomarkers were associated with mortality and recurrence-free time. The role of the different MMPs analyzed during the study do not have the same prognostic implications after this kind of surgery.

PPy@Fe3O4 Nanoparticles Inhibit Tumor Growth and Metastasis Through Chemodynamic and Photothermal Therapy in Non-small Cell Lung Cancer

Non-small cell lung cancer (NSCLC) is considered to be a principal cause of cancer death across the world, and nanomedicine has provided promising alternatives for the treatment of NSCLC in recent years. Photothermal therapy (PTT) and chemodynamic therapy (CDT) have represented novel therapeutic modalities for cancer treatment with excellent performance. The purpose of this research was to evaluate the effects of PPy@Fe₃O₄ nanoparticles (NPs) on inhibiting growth and metastasis of NSCLC by combination of PTT and CDT. In this study, we synthesized PPy@Fe₃O₄ NPs through a very facile electrostatic absorption method. And we detected reactive oxygen species production, cell apoptosis, migration and protein expression in different groups of A549 cells and established xenograft models to evaluate the effects of PPy@Fe₃O₄ NPs for inhibiting the growth of NSCLC. The results showed that the PPy@Fe₃O₄ NPs had negligible cytotoxicity and could efficiently inhibit the cell growth and metastasis of NSCLC in vitro. In addition, the PPy@Fe₃O₄ NPs decreased tumor volume and growth in vivo and endowed their excellent MRI capability of observing the location and size of tumor. To sum up, our study displayed that the PPy@Fe₃O₄ NPs had significant synergistic effects of PTT and CDT, and had good biocompatibility and safety in vivo and in vitro. The PPy@Fe₃O₄ NPs may be an effective drug platform for the treatment of NSCLC.

Matrix Metalloproteinase-9 (MMP-9) Elevated in Serum but not in Bronchial Lavage Fluid in Patients with Lung Cancer

Aims and Background

Matrix metalloproteinase (MMP) family member MMP-9 degrades type IV collagen, which is one of the main constituents of the basement membrane. MMP-9 is closely associated with the invasive and metastatic potential of most types of lung cancer. In this study we investigated the levels of MMP-9 in serum and bronchial lavage fluid from lung cancer patients and compared them with the levels in patients with nonmalignant lung disease. We also attempted to clarify the possible relationship between serum and bronchial lavage fluid MMP-9 levels and histopathology, staging and metastasis of lung cancer.

Study Design

The study group consisted of 34 patients with lung cancer. The control group comprised 21 patients with nonmalignant lung disease. MMP-9 levels in serum and bronchial lavage fluid were evaluated by ELISA.

Results

MMP-9 levels in serum samples from the group with malignant disease were significantly higher than those from the control group (P <0.05). Bronchial lavage MMP-9 levels did not differ significantly between the two groups (P >0.05). Serum MMP-9 levels were two-fold higher than those in bronchial lavage, but there was no correlation between bronchial lavage and serum levels in both groups (r = 0.18, P >0.05). In the group with malignant disease, MMP-9 levels in serum and bronchial lavage fluid did not show any relationship with histopathological type and tumor stage. There was a statistically significant correlation between serum MMP-9 levels and local tumor stage in smoking nonsmall cell lung cancer (NSCLC) patients (r = 0.33, P <0.05). Karnofsky scores of lung cancer patients were inversely correlated with MMP-9 levels of serum (r = -0.39, P <0.05) but not of bronchial lavage fluid.

Conclusion

From our data it can be concluded that MMP-9 levels of serum but not of bronchial lavage fluid can be helpful in differentiating between malignant and benign lung diseases, and are related to the local stage in NSCLC patients and general clinical status of lung cancer patients.

Angiogenesis: Basic Mechanisms and Clinical Applications

The development and maintenance of an adequate vascular supply is critical for the viability of normal and neoplastic tissues. Angiogenesis, the development of new blood vessels from preexisting capillary networks, plays an important role in a number of physiologic and pathologic processes, including reproduction, wound repair, inflammatory diseases, and tumor growth. Angiogenesis involves sequential steps that are triggered in response to angiogenic growth factors released by inflammatory, mesenchymal, or tumor cells that act as ligands for endothelial cell receptor tyrosine kinases. Stimulated endothelial cells detach from neighboring cells and migrate, proliferate, and form tubes. The immature tubes are subsequently invested and stabilized by pericytes or smooth muscle cells. Angiogenesis depends upon complex interactions among various classes of molecules, including adhesion molecules, proteases, structural proteins, cell surface receptors, and growth factors. The therapeutic manipulation of angiogenesis targeted against ischemic and neoplastic diseases has been investigated in preclinical animal models and in clinical trials. Proangiogenic trials that have stimulated vessel growth in ischemic coronary or peripheral tissues through expression, delivery, or stimulated release of growth factors have shown efficacy in animal models and mixed results in human clinical trials. Antiangiogenic trials have used strategies to block the function of molecules critical for new vessel growth or maturation in the treatment of a variety of malignancies, mostly with results less encouraging than those seen in preclinical models. Pro-and antiangiogenic clinical trials demonstrate that strategies for optimal drug delivery, dosing schedules, patient selection, and endpoint measurements need further investigation and refinement before the therapeutic manipulation of angiogenesis will realize its full clinical potential.

Matrix metalloproteinase-2 -1306 C>T gene polymorphism is associated with reduced risk of cancer: a meta-analysis

Matrix metalloproteinase-2 (MMP2) is an endopeptidase, mainly responsible for degradation of extracellular matrix components, which plays an important role in cancer disease. A single nucleotide polymorphism (SNP) at -1306 disrupts a Sp1-type promoter site. The results from the published studies on the association between MMP2 -1306 C>T polymorphism and cancer risk are contradictory and inconclusive. In the present study, a meta-analysis was therefore performed to evaluate the strength of any association between the MMP2 -1306 C>T polymorphism and risk of cancer. We searched all eligible studies published on association between MMP2 -1306 C>T polymorphism and cancer risk in PubMed (Medline), EMBASE and Google Scholar online web databases until December 2013. Genotype distribution data were collected to calculate the pooled odds ratios (ORs) and 95% confidence intervals (95%CIs) to examine the strength of the association. A total of 8,590 cancer cases and 9,601 controls were included from twenty nine eligible case control studies. Overall pooled analysis suggested significantly reduced risk associated with heterozygous genotype (CT vs CC: OR=0.758, 95%CI=0.637 to 0.902, p=0.002) and dominant model (TT+CT vs CC: OR=0.816, 95%CI=0.678 to 0.982, p=0.032) genetic models. However, allelic (T vs C: OR=0.882, 95%CI=0.738 to 1.055, p=0.169), homozygous (TT vs CC: OR=1.185, 95%CI=0.825 to 1.700, p=0.358) and recessive (TT vs CC+CT: OR=1.268, 95%CI=0.897 to 1.793, p=0.179) models did not show any risk. No evidence of publication bias was detected during the analysis. The results of present meta-analysis suggest that the MMP2 -1306 C>T polymorphism is significantly associated with reduced risk of cancer. However, further studies with consideration of different populations will be required to evaluate this relationship in more detail.

Mucin1 promotes the migration and invasion of hepatocellular carcinoma cells via JNK-mediated phosphorylation of Smad2 at the C-terminal and linker regions

Mucin1 (MUC1), as an oncogene, plays a key role in the progression and tumorigenesis of many human adenocarcinomas. In this study, wound-healing, transwell migration and matrigel invasion assays showed that MUC1 promotes human hepatocellular carcinoma (HCC) cell migration and invasion by MUC1 gene silencing and overexpressing. Treatment with exogenous transforming growth factor beta (TGF-β)1, TGF-β type I receptor (TβRI) inhibitor, TGF-β1 siRNAs, or activator protein 1 (AP-1) inhibitor to MUC1-overexpressing HCC cells revealed that MUC1-induced autocrine TGF-β via JNK/AP-1 pathway promotes the cell migration and invasion. In addition, the migration and invasion of HCC cells were more significantly inhibited by JNK inhibitor compared with that by TβRI inhibitor or TGF-β1 siRNAs. Further studies demonstrated that MUC1-mediated JNK activation not only enhances the phosphorylation of Smad2 C-terminal at Ser-465/467 site (Smad2C) through TGF-β/TβRI, but also directly enhances the phosphorylation of Smad2 linker region at Ser-245/250/255 site (Smad2L), and then both of them collaborate to upregulate matrix metalloproteinase (MMP)-9-mediated cell migration and invasion of HCC. These results indicate that MUC1 is an attractive target in liver cancer therapy.

The matrix metalloproteinase-7 and pro-enzyme of metalloproteinase-1 as a potential marker for patients with rectal cancer without distant metastasis

The aim of this study was the evaluation of clinical usage of metalloproteinase (MMP): proMMP-1, MMP-2, MMP-7, MMP-9, tissue inhibitors of metalloproteinase (TIMP)-1 and TIMP-2 in serum of patients with rectal cancer, as well as the selection of parameters of the greatest diagnostic sensitivity and the determination of their relation with clinicopathological features, what is more, the demonstration whether their concentrations may have a prognostic value in the assessment of disease-free survival (DFS) and overall survival (OS). The study comprised 100 patients with rectal cancer including 29 women and 71 men. The tested group was comprised of qualified patients without distant metastasis (M0). It was demonstrated that in patients with rectal cancer, the concentrations of MMP-9, MMP-7, and proMMP-1 as well as TIMP-1 were significantly higher in comparison to the reference group. On the basis of ROC curves, the greatest diagnostic sensitivity of MMP-9 was demonstrated. When evaluating the correlation of tested parameters with the size of the tumor (T1-T2 vs T3-T4), essential differences were shown for proMMP-1 concentrations. The highest percentage of patients with progression had an increased concentration of MMP-7 and TIMP-1. During a 5-year follow-up, univariate log-rank analysis had shown an essential dependence between the concentration of MMP-7 in men and DSF which was confirmed in Cox multivariate analysis. It was demonstrated that the pretreatment concentration of proMMP-1 may be clinically useful when evaluating the mass of the tumor, whereas MMP-7 may be a prognostic factor for DFS in men with rectal cancer without distant metastasis.

ADAM9 up-regulates N-cadherin via miR-218 suppression in lung adenocarcinoma cells

Lung cancer is the leading cause of cancer death worldwide, and brain metastasis is a major cause of morbidity and mortality in lung cancer. CDH2 (N-cadherin, a mesenchymal marker of the epithelial-mesenchymal transition) and ADAM9 (a type I transmembrane protein) are related to lung cancer brain metastasis; however, it is unclear how they interact to mediate this metastasis. Because microRNAs regulate many biological functions and disease processes (e.g., cancer) by down-regulating their target genes, microRNA microarrays were used to identify ADAM9-regulated miRNAs that target CDH2 in aggressive lung cancer cells. Luciferase assays and western blot analysis showed that CDH2 is a target gene of miR-218. MiR-218 was generated from pri-mir-218-1, which is located in SLIT2, in non-invasive lung adenocarcinoma cells, whereas its expression was inhibited in aggressive lung adenocarcinoma. The down-regulation of ADAM9 up-regulated SLIT2 and miR-218, thus down-regulating CDH2 expression. This study revealed that ADAM9 activates CDH2 through the release of miR-218 inhibition on CDH2 in lung adenocarcinoma.

Inhibition of c-Met promoted apoptosis, autophagy and loss of the mitochondrial transmembrane potential in oridonin-induced A549 lung cancer cells

OBJECTIVE

Herein, inhibition of hepatocyte growth factor receptor, c-Met, significantly increased cytochrome c release and Bax/Bcl-2 ratio, indicating that c-Met played an anti-apoptotic role. The following experiments are to elucidate this anti-apoptotic mechanism, then the effect of c-Met on autophagy has also been discussed.

METHODS

Investigated was the influence of c-Met on apoptosis, autophagy and loss of mitochondrial transmembrane potential (Δψm), and the relevant proteins were examined.

KEY FINDINGS

First, we found that activation of extracellular signal-regulated kinase (ERK), p53 was promoted by c-Met interference. Subsequent studies indicated that ERK was the upstream effector of p53, and this ERK-p53 pathway mediated release of cytochrome c and up-regulation of Bax/Bcl-2 ratio. Secondly, the inhibition of c-Met augmented oridonin-induced loss of mitochondrial transmembrane potential (Δψm), resulting apoptosis. Finally, the inhibition of c-Met increased oridonin-induced A549 cell autophagy accompanied by Beclin-1 activation and conversion from microtubule-associated protein light chain 3 (LC3)-I to LC3-II. Activation of ERK-p53 was also detected in autophagy process and could be augmented by inhibition of c-Met. Moreover, suppression of autophagy by 3-methyladenine (3-MA) or small interfering RNA against Beclin-1 or Atg5 decreased oridonin-induced apoptosis. Inhibition of apoptosis by pan-caspase inhibitor (z-VAD-fmk) decreased oridonin-induced autophagy as well and Loss of Δψm also occurred during autophagic process.

CONCLUSION

Thus, inhibiting c-Met enhanced oridonin-induced apoptosis, autophagy and loss of Δψm in A549 cells.

CD133 affects the invasive ability of HCT116 cells by regulating TIMP-2

CD133 is widely expressed in colorectal cancer (CRC) tissues and cell lines. This protein has been used as a marker of CRC cancer stem cells, although the function and mechanism of CD133 in CRC invasion and metastasis remain unclear. In our study, we examined the role of CD133 in CRC invasion in vitro and investigated the mechanism involved in CD133-related invasion. CD133(high) and CD133(low) HCT116 cells were isolated, and the proliferation and invasive ability of these two subpopulations were tested. CD133(high) HCT116 cells exhibited greater proliferation and invasion compared with CD133(low) HCT116 cells. CD133 knockdown (using CD133 small-interfering [si]RNA) inhibited the invasive activity of CD133si-HCT116 cells. For the first time, we found that the expression of tissue inhibitor of matrix metalloproteinases-2 (TIMP-2) was down-regulated in CD133si-HCT116 cells. In addition, for the TIMP-2si-HCT116 cells (transfected with TIMP-2 siRNA), in vitro invasion was significantly decreased, whereas the expression of CD133 remained unchanged. Finally, the metalloproteinase 2 and MEK/ERK signaling pathways were examined, and no significant change was observed after the knockdown of CD133 or TIMP-2 in HCT116 cells. In conclusion, we demonstrated that CD133 plays an important role in HCT116 cell invasion, and for the first time, we found that CD133 knockdown significantly down-regulated TIMP-2 expression, which suggests that CD133 affects the invasive ability of HCT116 cells by regulating TIMP-2.

Menadione : sodium orthovanadate combination eliminates and inhibits migration of detached cancer cells

Exposure of cancer cells to anticancer agents in cultures induces detachment of cells that are usually considered dead. These drug-induced detached cells (D-IDCs) may represent a clinical problem for chemotherapy since they may survive anoikis, enter the circulation, invade other tissues and resume proliferation, creating a metastasis, especially in tissues where the bioavailability of anticancer agents is not enough to eliminate all cancer cells. In this study we evaluated the antiproliferative effect of menadione : sodium orthovanadate (M : SO) combination on A549 lung cancer cells as well as the ability of M : SO to induce cell detachment. In addition, we followed the fate and chemosensitivity of M : SO-induced detached cells. Using transwell chambers, we found that a fraction of the M : SO-induced detached cells were viable and, furthermore, were able to migrate, re-attach, and resume proliferation when re-incubated in drug-free media. The total elimination of A549 detachment-resistant cells and M : SO-induced detached cells were successfully eliminated by equivalent M : SO concentration (17.5 μM : 17.5 μM). Thus, M : SO prevented cell migration. Similar results were obtained on DBTRG.05MG human glioma cells. Our data guarantee further studies to evaluate the in vivo occurrence of D-IDCs, their implications for invasiveness and metastasis and their sensitivity to anticancer drugs.

Activation of ERK-p53 and ERK-mediated phosphorylation of Bcl-2 are involved in autophagic cell death induced by the c-Met inhibitor SU11274 in human lung cancer A549 cells

SU11274, a small molecule inhibitor of c-Met, was reported to induce apoptosis in human non-small-cell lung cancer (NSCLC) cells. However, SU11274-mediated autophagy in NSCLC cells has rarely been reported. The aim of this study was to elucidate the molecular mechanisms mediating SU11274-induced autophagy in NSCLC A549 cells. Here we reported that SU11274-induced autophagy was accompanied with an increase in the conversion of LC3-I to LC3-II and up-regulation of Beclin-1 expression. Subsequently, we also found that small interfering RNA against c-Met induced A549 cell autophagy while promotion of c-Met by hepatocyte growth factor (HGF) suppressed A549 cell autophagy. Inhibition of autophagy by 3-methyladenine (3-MA) suppressed SU11274-induced cell death, suggesting that SU11274-induced autophagy caused cell death. Further study showed that ERK and p53 were activated after SU11274 treatment. Interruption of ERK and p53 activities decreased SU11274-induced autophagy, and blocking of ERK by the specific inhibitor PD98059 suppressed SU11274-induced p53 activation. Moreover, ERK activation upregulated Beclin-1 expression through induction of Bcl-2 phosphorylation, but p53 did not induce Bcl-2 phosphorylation. In conclusion, inhibition of c-Met induced autophagic cell death, which was associated with ERK-p53 activation and ERK-mediated Bcl-2 phosphorylation in A549 cells.

Regulation of matrix metalloproteinase genes by E2F transcription factors: Rb-Raf-1 interaction as a novel target for metastatic disease

The retinoblastoma (Rb)-E2F transcriptional regulatory pathway plays a major role in cell-cycle regulation, but its role in invasion and metastasis is less well understood. We find that many genes involved in the invasion of cancer cells, such as matrix metalloproteinases (MMP), have potential E2F-binding sites in their promoters. E2F-binding sites were predicted on all 23 human MMP gene promoters, many of which harbored multiple E2F-binding sites. Studies presented here show that MMP genes such as MMP9, MMP14, and MMP15 which are overexpressed in non-small cell lung cancer, have multiple E2F-binding sites and are regulated by the Rb-E2F pathway. Chromatin immunoprecipitation assays showed the association of E2F1 with the MMP9, MMP14, and MMP15 promoters, and transient transfection experiments showed that these promoters are E2F responsive. Correspondingly, depletion of E2F family members by RNA interference techniques reduced the expression of these genes with a corresponding reduction in collagen degradation activity. Furthermore, activating Rb by inhibiting the interaction of Raf-1 with Rb by using the Rb-Raf-1 disruptor RRD-251 was sufficient to inhibit MMP transcription. This led to reduced invasion and migration of cancer cells in vitro and metastatic foci development in a tail vein lung metastasis model in mice. These results suggest that E2F transcription factors may play a role in promoting metastasis through regulation of MMP genes and that targeting the Rb-Raf-1 interaction is a promising approach for the treatment of metastatic disease.

Tectoridin, an isoflavone glycoside from the flower of Pueraria lobata, prevents acute ethanol-induced liver steatosis in mice

In traditional Chinese medicine, the flower of Pueraria lobata (Puerariae Flos) has been used in therapy to counteract the problems associated with alcohol drinking and liver injury. In this study, we investigated the hepatoprotective effects and its mechanisms of tectoridin, an isoflavone glycoside from the flower of P. lobata (Willd.) Ohwi. Ethanol (5g/kg) was given orally every 12h for a total of three doses. 1h after the last dose of ethanol, tectoridin (25, 50 and 100mg/kg) was given intragastrically five times in three consecutive days. The mice were sacrificed at 4h after tectoridin treatment. Peroxisome proliferators-activated receptor alpha (PPARalpha), sterol regulatory element-binding protein (SREBP)-1c and their target genes were evaluated by biochemical analysis and quantitative real-time polymerase chain reaction (qPCR). Mitochondria were isolated for the mitochondrial permeability transition (MPT) and membrane potential (DeltaPsi(m)) assay. Acute ethanol exposure resulted in the significant increase of the alanine aminotransferase (ALT), aspartate aminotransferase (AST) and triglyceride (TG) levels and hepatic mitochondria dysfunction shown as the increase of MPT and the decrease of DeltaPsi(m). However, tectoridin treatment dramatically attenuated these effects. In addition, tectoridin remarkably alleviated the over-production of thiobarbituric acid-reactive substance. Furthermore, tectoridin inhibited the decrease of PPARalpha expression and its target genes, including medium-chain acyl-CoA dehydrogenase (MCAD), acyl-CoA oxidase (ACO) and cytochrome P450 4A (CYP 4A) at mRNA and enzyme activity levels. These data showed that tectoridin protected against ethanol-induced liver steatosis mainly through modulating the disturbance of PPARalpha pathway and ameliorating mitochondrial function.

Expression of tissue inhibitors of metalloproteinase 1 (TIMP-1) in gastric cancer tissue

Degradation of extracellular matrix (ECM) is an essential step of invasion and metastasis of gastric cancer. The proteolysis of basement membranes depends on the balance between activities of matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs). The aim of the study was to assess the expression of TIMP-1 in gastric cancer (GC) and interstitial inflammatory infiltrate cells within GC tissue in relation to clinico-pathological features of tumor and to estimate the prognostic significance of TIMP-1 expression for patients' survival. The presence of TIMP-1 in 54 cases of gastric cancer samples was investigated by immunohistochemistry. The expression of TIMP-1 in cancer and interstitial inflammatory infiltrate cells was evaluated in semi-quantitative scale. The immunoreactivity of TIMP-1 in cancer and inflammatory cells was positive in 100% of cases and varied from weak to intense reaction. The intensity of TIMP-1 expression increased with more advanced tumor stages and in patients who died of cancer during 2-year observation. TIMP-1 expression in interstitial inflammatory infiltrate cells was the independent prognostic factor for patients' survival. The results suggest the role of TIMP-1 in gastric tumorigenesis, although this issue requires further investigtions.

Inhibition of Na(+)/H(+) exchanger 1 by 5-(N-ethyl-N-isopropyl) amiloride reduces hypoxia-induced hepatocellular carcinoma invasion and motility

Na(+)/H(+) exchanger 1 (NHE1) plays a significant role in tumor metastasis. However, the exact mechanisms by which NHE1 mediates cell invasion and migration, especially in hepatocellular carcinoma (HCC), are not yet known. In the current study, we show for the first time that the inhibition of NHE1 by 5-(N-ethyl-N-isopropyl) amiloride (EIPA) is able to suppress migration and invasion of HepG2 cells under hypoxic conditions. In addition, hypoxia activated ERK1/2, which in turn promoted the production of MMP-2, MMP-9 and VEGF. EIPA's suppressive role was determined to act through down-regulation of MMP-2, MMP-9 and VEGF in an ERK1/2 dependent manner. The data demonstrate that NHE1 plays a role in HCC invasion and that NHE1 may be a potential therapeutic target for HCC treatment.

Current concepts on the role of inflammation in COPD and lung cancer

Chronic obstructive pulmonary disease (COPD) and lung cancer are leading cause of death, and both are associated with cigarette smoke exposure. It has been shown that 50-70% of patients diagnosed with lung cancer suffer from COPD, and reduced lung function is an important event in lung cancer suggesting an association between COPD and lung cancer. However, a causal relationship between COPD and lung tumorigenesis is not yet fully understood. Recent studies have suggested a central role of chronic inflammation in the pathogenesis of both the diseases. For example, immune dysfunction, abnormal activation of NF-kappaB, epithelial-to-mesenchymal transition, altered adhesion signaling pathways, and extracellular matrix degradation/altered signaling are the key underlying mechanisms in both COPD and lung cancer. These parameters along with other processes, such as chromatin modifications/epigenetic changes, angiogenesis, and autophagy/apoptosis are altered by cigarette smoke, are crucial in the development of COPD and lung cancer. Understanding the cellular and molecular mechanisms underlying these processes will provide novel avenues for halting the chronic inflammation in COPD and devising therapeutic strategies against lung cancer.

Beyond doublet chemotherapy for advanced non-small-cell lung cancer: combination of targeted agents with first-line chemotherapy

The first-line treatment of advanced non-small-cell lung cancer (NSCLC) has evolved significantly over the past 5 years. As recently as 15 years ago, best supportive care (BSC) was considered an acceptable option for most patients with advanced or metastatic NSCLC, based on the concern that toxic effects of systemic chemotherapy overshadowed any potential benefits. The enhanced efficacy of platinum-based doublet chemotherapeutic regimens led to increases in overall patient survival relative to BSC. However, overall survival (OS) appeared to plateau, even with the introduction and refinement of these regimens. The addition of novel targeted agents targeting growth pathways to platinum-based regimens failed to overcome the 7.8- to 10.5-month survival barrier. After many phase III clinical trials, which involved tyrosine kinase inhibitors, matrix metalloproteinase inhibitors, protein kinase C inhibitors, and retinoids, this survival barrier had yet to be surmounted, although in some cases certain subgroups benefited, suggesting specific molecular correlations. Recently, inhibition of components of the angiogenesis pathway with the addition of bevacizumab to a platinum-based doublet led to statistically significant increases in OS, progression-free survival, and response rate relative to chemotherapy alone. This advance pushed the median survival of selected patients with advanced or metastatic NSCLC who met the eligibility criteria of the trial over the 12-month mark, thus offering patients and clinicians hope for more incremental advances in the future.

Hypercoagulability and lung cancer

The relationship between cancer and coagulopathy was suggested by Trousseau nearly 150 years ago. Later, it became more evident that oncologic patients are at a higher risk of experiencing thromboembolic events. This can be due to activation of the coagulation system either by neoplastic cells or by prescribed therapies (chemotherapy or surgical procedures). In fact, these events can constitute the first manifestation of cancer, and their recurrence, despite efficient anticoagulation, has been described. The coagulation system is normally activated in order to provide healing. In the presence of neoplasms, this complex system is activated as a response to multiple stimuli and seems to contribute to cancer progression. Activation of the coagulation system has a greater effect on metastatic foci than on the primary tumor. However, most cancer victims die from complications caused by metastasis, which underscores the importance of this theme. In this area, various mechanisms have been described, creating promising perspectives for future treatments. The current success in using low-molecular-weight heparins against small cell lung cancer is encouraging. Although the knowledge of those mechanisms is relatively incipient, many basic research and clinical studies are underway.

[Tumor vasculature as a therapeutic target in non-small cell lung cancer]

Despite developments in conventional (chemo)radiotherapy and surgery, survival of non-small cell lung cancer (NSCLC) patients remains poor. Treatments with targeted molecular drugs offer novel therapeutic strategies. Bevacizumab, a recombinant anti-vascular endothelial growth factor (VEGF) antibody, is the antiangiogenic drug at the most advanced stage of development in the therapy of NSCLC. However, a number of questions and future challenges relating to the use of bevacizumab in NSCLC remain. Furthermore, novel agents targeting the pre-existing NSCLC vasculature (i.e. vascular disrupting agents, VDAs) or multiple tyrosine kinase inhibitors have emerged as unique drug classes delivering promising results in several preclinical and clinical studies. Herein, we review the most recent data using these novel targeted agents either alone or in combination with chemotherapy in NSCLC.

Sodium hydrogen exchanger and phospholipase D are required for alpha1-adrenergic receptor stimulation of metalloproteinase-9 and cellular invasion in CCL39 fibroblasts

Matrix metalloproteinase 9 (MMP-9) plays a critical role in digesting the extracellular matrix and has a vital function in tumor metastasis and invasion; this protease activity is significantly increased in non-small cell lung cancers. The sodium hydrogen exchanger isoform 1 (NHE1) functions as a focal point for signal coordination and cytoskeletal reorganization. NHE1 is thought to play a central role in establishing signaling components at the leading edge of a migrating cell. Therefore, we studied the relationship between NHE1 and MMP-9 activity in Chinese hamster lung fibroblasts (CCL39) stimulated with phenylephrine (PE). We show that PE increases MMP-9 gelatinolytic activity in CCL39 cells. The inhibition of phospholipase D (PLD) signaling abrogated PE-induced MMP-9 activity. The role of PLD as an essential signaling intermediate was confirmed when the addition of permeable phosphatidic acid increased MMP-9 activity in the same cells. PE-induced invasion was increased 1.9-fold over controls and the PE response was lost when 1-butanol was used to block PLD signaling. Cells pre-treated with the NHE1 inhibitor, 5-(N-ethyl-N-isopropyl) amiloride (EIPA) prior to PE addition resulted in a notable decrease in MMP-9 activation and cell invasion as compared to untreated PE-stimulated cells. CCL39 NHE1 null cells demonstrated no increase in MMP-9 protease activity or cell invasion in response to PE treatment. Reconstitution of NHE1 expression recovered the PE-induced activation of protease activity and cell invasion. MMP-9 processing was altered in cells expressing a proton transport defective NHE1 but retained the ability to respond to PE. Conversely, cells expressing an ezrin, radixin, moesin (ERM)-binding deficient NHE1 had a lower MMP-9 activity and the protease did not respond to PE addition. Parallel studies on NCI-H358 non-small cell lung cancer (NSCL) cells showed that PE stimulated both MMP-9 activity and cell invasion in an NHE1 dependent manner. This work describes for the first time a PE-induced relationship between NHE1 and MMP-9 and a new potential mechanism by which NHE1 could promote tumor formation and metastasis.

Extracellular matrix regulation of drug resistance in small-cell lung cancer

PURPOSE

Lung cancer is the leading cause of cancer deaths in the developed world. Small cell lung cancer (SCLC) has the worst prognosis due to the emergence of resistance to chemotherapy. This article will review recent work that has defined mechanisms of chemo-resistance focusing on the role of integrins.

RESULTS

SCLC is surrounded by an extensive stroma of extracellular matrix (ECM) and high levels of expression correlate with poor prognosis. ECM protects SCLC cells against chemotherapy-induced cell death by activating beta1 integrins leading to activation of phosphoinositide-3-OH kinase (PI3-kinase), which prevents etoposide-induced caspase-3 activation and subsequent apoptosis. Engagement of ECM prevents etoposide and radiation induced G2/M cell cycle arrest in SCLC cells by blocking the up-regulation of p21Cip1/WAF1 and p27Kip1 and the down-regulation of cyclins E, A and B. These effects are abrogated by pharmacological and genetic inhibition of PI3-kinase signalling.

CONCLUSIONS

Thus, ECM via beta1 integrin-mediated PI3-kinase activation allows SCLC cells to survive treatment induced cell cycle arrest and apoptosis with persistent DNA damage, providing a model to account for the emergence of acquired drug resistance. Novel therapeutic strategies may therefore be directed at inhibiting integrin-mediated cell survival signals improving response rates and cure in this devastating cancer.

MMP-2, TIMP-2 and CD44v6 Expression in Non-small-cell Lung Carcinomas

Introduction: Factors that emerge as crucial participants in tumour invasion and metastases are matrix metalloproteinases (MMPs), tissue inhibitor of metalloproteinase (TIMP) inhibitors and cellular adhesion molecules (CD44 and similar molecules). They play important roles in tumour invasion and metastasis in non-small-cell lung carcinomas (NSCLCs). Materials and Methods: The study was performed using the data of 33 patients. MMP-2 from the metalloproteinase family, TIMP-2 from the metalloproteinase inhibitor family and the adhesion molecule CD44v6 expression were investigated immunohistochemically to search their role in the metastasis and the clinical outcome of the patients with NSCLCs. Results: Twenty-three tumours (70%) were squamous cell carcinoma (SCC), 9 (27%) were adenocarcinoma (AC), and 1 (3%) was large cell carcinoma (LCC). MMP-2 and TIMP-2 were expressed in high rates in NSCLC but CD44v6 expression was about 50%. Lymphatic invasion was less frequent in TIMP-2-positive patients and this difference was statistically significant (P = 0.005). There was a statistically significant difference between SCCs and ACs with respect to CD44v6 tumoral expression (P = 0.004). Also, there was a negative correlation between lymphatic invasion and the extent of CD44v6; lymphatic invasion was significantly less in CD44v6-positive cases (P = 0.013). Conclusion: We found that TIMP-2 and CD44v6 can decrease the lymphatic invasion in NSCLCs. Also there was observed histiotype-related pattern of CD44v6 variant expression in SCCs. Key words: Immunohistochemistry, Metastasis, Pulmonary neoplasms

Matrix Metalloproteinases in Kidney Disease Progression and Repair: A Case of Flipping the Coin

Matrix metalloproteinases (MMPs) have pleiotropic enzymatic actions that go far beyond degradation of extracellular matrix. Both the multiplicity of their targets and the complexity of their regulation account for a variety of biological effects. In renal diseases, MMP effects may be different and/or opposite during the different phases of the pathology evolution. The major challenge with future therapeutic interventions using MMP inhibitors remains how to accomplish temporal and spatial control of their activity without flipping the coin.

Influence of MMP-2 and MMP-9 promoter polymorphisms on gene expression and clinical outcome of non-small cell lung cancer

Matrix metalloproteinases (MMP) including MMP-2 and MMP-9 play a major role in tumour invasion by proteolysing the extracellular matrix. Their activation, particularly that of MMP-9, is partly dependent on plasmin that is inhibited by TFPI-2 (tissue factor pathway inhibitor-2), a serine protease inhibitor whose gene expression is decreased in about one-third of non-small cell lung cancers (NSCLC). In addition, MMP-2 and MMP-9 are essential in the development of NSCLC and can be regulated by functional promoter polymorphisms. In this study, the -1306C/T MMP-2, -735C/T MMP-2 and -1562C/T MMP-9 polymorphisms were analysed in 90 NSCLC patients and 90 controls. In addition, the promoter region of the TFPI-2 gene was screened for sequence variations in both groups by DHPLC. A -167G/A polymorphism was identified in 3% of controls whereas none of the 90 patients exhibited this genetic variation in the TFPI-2 promoter region. Moreover, no difference in -1306C/T MMP-2, -735C/T MMP-2 and -1562C/T MMP-9 genotypes was found between cases and controls. However, the homozygous -1562CC MMP-9 genotype was more frequent in patients with squamous cell carcinoma than in controls (p=0.018). When genotype distributions were compared to MMP-2 and MMP-9 gene expression in tumours, no relationship was found with the -1306 MMP-2 and -1562 MMP-9 polymorphisms. In contrast, tumour MMP-2 gene expression was lower in homozygous -735CC patients than in those with CT or TT genotypes. In addition, the survival time was longer in patients with the MMP-2 -735T allele than in those with the CC genotype (p=0.02). The relative risk of death was increased 2.6-fold in -735CC patients (p=0.045; 95% CI=1.0-6.7). The results of this study suggest that the -735C/T MMP-2 polymorphism might be an independent prognostic marker in NSCLC, but this should be confirmed in a larger cohort of patients.

Anti-angiogenic drugs: from bench to clinical trials

Angiogenesis, the generation of new capillaries through a process of pre-existing microvessel sprouting, is under stringent control and normally occurs only during embryonic and post-embryonic development, reproductive cycle, and wound repair. However, in many pathological conditions (solid tumor progression, metastasis, diabetic retinopathy, hemangioma, arthritis, psoriasis and atherosclerosis among others), the disease appears to be associated with persistent upregulated angiogenesis. The development of specific anti-angiogenic agents arises as an attractive therapeutic approach for the treatment of cancer and other angiogenesis-dependent diseases. The formation of new blood vessels is a complex multi-step process. Endothelial cells resting in the parent vessels are activated by an angiogenic signal and stimulated to synthesize and release degradative enzymes allowing endothelial cells to migrate, proliferate and finally differentiate to give rise to capillary tubules. Any of these steps may be a potential target for pharmacological intervention. In spite of the disappointing results obtained initially in clinical trials with anti-angiogenic drugs, recent reports with positive results in phases II and III trials encourage expectations in their therapeutic potential. This review discusses the current approaches for the discovery of new compounds that inhibit angiogenesis, with emphasis on the clinical developmental status of anti-angiogenic drugs.

Inhibition of invasion, angiogenesis, tumor growth, and metastasis by adenovirus-mediated transfer of antisense uPAR and MMP-9 in non-small cell lung cancer cells

Lung cancer is currently the leading cause of cancer deaths in the United States. Conventional therapeutic treatments, including surgery, chemotherapy, and radiation therapy, have achieved only limited success. The overexpression of proteases, such as urokinase-type plasminogen activator (uPA), its receptor (uPAR), and matrix metalloproteinases (MMP), is correlated with the progression of lung cancer. In the present study, we used a replication-deficient adenovirus capable of expressing antisense uPAR and antisense MMP-9 transcripts to simultaneously down-regulate uPAR and MMP-9 in H1299 cells. Ad-uPAR-MMP-9 infection of H1299 cells resulted in a dose- and time-dependent decrease of uPAR protein levels and MMP-9 activity as determined by Western blotting and gelatin zymography, respectively. Corresponding immunohistochemical analysis also showed that Ad-uPAR-MMP-9 infection inhibited uPAR and MMP-9 expression. As shown by Boyden chamber assay, Ad-uPAR-MMP-9 infection significantly decreased the invasive capacity of H1299 cells compared with mock and Ad-CMV (empty vector)-infected cells in vitro. Furthermore, Ad-uPAR-MMP-9 infection inhibited capillary-like structure formation in H1299 cells cocultured with endothelial cells in a dose-dependent manner compared with mock- and Ad-CMV-infected cells. Ad-uPAR-MMP-9 injection caused the regression of s.c. induced tumors after s.c. injection with H1299 lung cancer cells and inhibited lung metastasis in the metastatic model with A549 cells. These data suggest that Ad-uPAR-MMP-9 shows its antitumor activity against both established and early phases of lung cancer metastases by causing the destruction of the tumor vasculature. In summary, adenovirus-mediated inhibition of uPA-uPAR interaction and MMP-9 on the cell surface may be a promising anti-invasion and antimetastatic strategy for cancer gene therapy.

Is tailored therapy feasible in oncology?

Tailored therapy aims to cure a patient who suffers from a specific disease with an effective and safe drug, based on the complex interactions among patient's characteristics, disease physiopathology and drug metabolism. Genomic and proteomic technologies represent promising new useful tools to understand cancer biology and molecular basis of interindividual differences of anticancer drugs efficacy. Genomic profiling seems to be able to re-classifying cancer into new molecular and prognostic homogeneous subgroups. By individual polymorphisms it is possible to identify the patients at higher risk for severe toxicity from those that may gain benefit from a particular treatment. The clinical use of targeted therapy is hampered by several questions, including: optimal biological dose, availability of surrogate biomarkers predictive of activity, schedule of administration, tumor histotype and stage to treat and modalities of combination with chemo/radiotherapy. In addition, further efforts are needed to improve the reliability of genomic and proteomic technologies. These unsolved issues presently make tailored therapy an open challenge.

Targeting an MMP-9-activated prodrug to multiple myeloma-diseased bone marrow: a proof of principle in the 5T33MM mouse model

Multiple myeloma (MM) is an incurable B-cell cancer characterised by the monoclonal proliferation of tumour cells in the bone marrow (BM). It has been described that matrix metalloproteinases (MMPs) and especially MMP-9 is secreted by MM cells. In this study, we investigated the possibility to exploit MMP-9 activity to activate prodrugs and to target MM cells as a new tumour-specific therapy. Cleavage of the prodrug EV1-FITC by MMP-9 resulted in release of fluorescence which can be used as a measure of prodrug activation. The 5T33MM mouse model was used in this proof-of-principle study. The prodrug was activated in a higher amount by addition to MMP-9-producing 5T33MMvv cells, homogenates from tumour-bearing organs (BM, spleen) and isolated 5T33MM-diseased BM and spleen cells compared to non-MMP-9-producing 5T33MMvt cells and homogenates/cells from non-tumour-bearing organs/mice, as measured by fluorescence release. This fluorescence release could be inhibited by the MMP-2/MMP-9-specific inhibitor, CTT. Activation of the prodrug in the 5T33MM spleen and BM homogenates was confirmed by chromatography. EV1-fluorescein isothiocyanate injection into 5T33MM-diseased animals resulted in a higher fluorescence release by the isolated BM and spleen cells compared to injection into healthy animals. In conclusion, MMP-9 activity can be used to activate prodrugs that target MM.

Phase I trial of the matrix metalloproteinase inhibitor marimastat combined with carboplatin and paclitaxel in patients with advanced non-small cell lung cancer

PURPOSE

Marimastat is an orally bioavailable inhibitor of matrix metalloproteinases. A phase I study was initiated to determine whether conventional doses of carboplatin and paclitaxel are tolerated when combined with marimastat and to assess the influence of marimastat on paclitaxel pharmacokinetics.

EXPERIMENTAL DESIGN

Three dose levels were evaluated. Marimastat (10 or 20 mg oral administration b.i.d.) was administered continuously with paclitaxel (175 or 200 mg/m(2) as a 3-hour i.v. infusion) and carboplatin (at a dose providing an area under the free drug plasma concentration-time curve of 7 mg min/mL) administered each 3 weeks. Toxicity and response were evaluated throughout the intended four cycles of combined therapy. The plasma pharmacokinetics of paclitaxel was determined in each patient both without concurrent marimastat and after receiving marimastat for 1 week.

RESULTS

Twenty-two chemotherapy-naive patients with stage IIIb (27%) or stage IV (73%) non-small cell lung cancer were enrolled. Their median age was 56 years (range, 39-73 years), 50% were female, and their performance status (Eastern Cooperative Oncology Group) ranged from 0 to 2. Treatment was well tolerated, as 18 (82%) of the patients completed all four cycles of chemotherapy without dose-limiting toxicity. Grade 2 musculoskeletal toxicities were reported in 3 of 12 patients receiving marimastat (20 mg b.i.d.). Nine patients required dose reductions, predominantly related to low-grade myelosuppression. Partial responses occurred in 12 of 21 (57%) evaluable patients with disease stabilization in another 5 (19%). Marimastat had no effect on paclitaxel pharmacokinetics.

CONCLUSIONS

The administration of marimastat (10 mg b.i.d.) with paclitaxel (200 mg/m(2)) and carboplatin at an area under the free drug plasma concentration-time curve of 7 mg min/mL was well tolerated with no apparent pharmacokinetic interaction. Study of this drug combination in the adjuvant setting should be considered if tissue inhibition of matrix metalloproteinase activity can first be shown.

Mouse models for human lung cancer

In recent years several new mouse models for lung cancer have been described. These include models for both non-small-cell lung cancer (NSCLC) and small-cell lung cancer (SCLC). Tumorigenesis in these conditional mouse tumor models can be initiated in adult mice through Cre-recombinase-induced activation of oncogenic mutations in a subset of the cells. They present a marked improvement over mouse models that depend on carcinogen induction of tumors. These models permit us to study the consecutive steps involved in initiation and progression and allow us to address questions like the cell of origin, and the role of cancer stem cells in the maintenance of these tumors. They now need to be validated as suitable preclinical models for intervention studies in which questions with respect to therapy response and resistance can be addressed.

Combination of antiangiogenic therapy with other anticancer therapies: results, challenges, and open questions

Angiogenesis is necessary for tumor growth. Drug discovery efforts have identified several potential therapeutic targets on endothelial cells and selective inhibitors capable of slowing tumor growth or producing tumor regression by blocking angiogenesis in in vivo tumor models. Certain antiangiogenic therapeutics increase the activity of cytotoxic anticancer treatments in preclinical models. More than 75 antiangiogenic compounds have entered clinical trials. Most of the early clinical testing was conducted in patients with advanced disease resistant to standard therapies. Several phase III trials have been undertaken to compare the efficacy of standard chemotherapy versus the same in combination with an experimental angiogenesis inhibitor. Preliminary results of the clinical studies suggest that single-agent antiangiogenic therapy is poorly active in advanced tumors. Although some of the results of combination trials are controversial, recent positive outcomes with an antivascular endothelial growth factor antibody combined with chemotherapy as front-line therapy of metastatic colorectal cancer have renewed enthusiasm for this therapeutic strategy. This article presents an overview of experimental and clinical studies of combined therapy with antiangiogenic agents and highlights the challenges related to the appropriate strategies for selection of the patients, study design, and choice of proper end points for preclinical and clinical studies using these agents.

Phase III study of matrix metalloproteinase inhibitor prinomastat in non-small-cell lung cancer

PURPOSE

Matrix metalloproteinases (MMPs) degrade extracellular proteins and facilitate tumor growth, invasion, metastasis, and angiogenesis. This trial was undertaken to determine the effect of prinomastat, an inhibitor of selected MMPs, on the survival of patients with advanced non-small-cell lung cancer (NSCLC), when given in combination with gemcitabine-cisplatin chemotherapy.

PATIENTS AND METHODS

Chemotherapy-naive patients were randomly assigned to receive prinomastat 15 mg or placebo twice daily orally continuously, in combination with gemcitabine 1,250 mg/m2 days 1 and 8 plus cisplatin 75 mg/m2 day 1, every 21 days for up to six cycles. The planned sample size was 420 patients.

RESULTS

Study results at an interim analysis and lack of efficacy in another phase III trial prompted early closure of this study. There were 362 patients randomized (181 on prinomastat and 181 on placebo). One hundred thirty-four patients had stage IIIB disease with T4 primary tumor, 193 had stage IV disease, and 34 had recurrent disease (one enrolled patient was ineligible with stage IIIA disease). Overall response rates for the two treatment arms were similar (27% for prinomastat v 26% for placebo; P = .81). There was no difference in overall survival or time to progression; for prinomastat versus placebo patients, the median overall survival times were 11.5 versus 10.8 months (P = .82), 1-year survival rates were 43% v 38% (P = .45), and progression-free survival times were 6.1 v 5.5 months (P = .11), respectively. The toxicities of prinomastat were arthralgia, stiffness, and joint swelling. Treatment interruption was required in 38% of prinomastat patients and 12% of placebo patients.

CONCLUSION

Prinomastat does not improve the outcome of chemotherapy in advanced NSCLC.

Matrix Metalloproteinase-12 Expression Correlates with Local Recurrence and Metastatic Disease in Non–Small Cell Lung Cancer Patients

Purpose: Non–small cell lung cancer (NSCLC) is a very common and aggressive malignancy. Survival after resection of tumor is especially determined by the occurrence of distant metastasis. Matrix metalloproteinases (MMP) support this metastatic process by degradation of the extracellular matrix.

Experimental Design: We used DNA microarray technology to examine the expression of 22 MMPs in 89 surgically treated NSCLC patients. Validation of microarray results was done using reverse transcription-PCR and immunohistology.

Results: MMP-1, MMP-9, and MMP-12 expression was significantly increased in tumors versus corresponding lung tissues. MMP-12 expression significantly correlated with local recurrence and metastatic disease. Multivariate Cox regression analysis revealed MMP-12 expression as an independent prognostic factor for tumor relapse–free interval. Gene expression analysis of 158 healthy tissues from 32 different organs revealed no MMP-12 expression in these organs and immunohistology identified MMP-12 protein in NSCLC only in tumor cells.

Conclusions: MMP-12 might be not only a prognostic marker, but also a valuable therapeutic target.

The effect of prinomastat (AG3340), a potent inhibitor of matrix metalloproteinase, on a new animal model of epiretinal membrane

PURPOSE

To develop a simple epiretinal membrane (ERM) animal model and evaluate the efficacy of prinomastat (AG3340), a synthetic inhibitor of matrix metalloproteinase.

METHODS

This experiment was carried out on 18 eyes of nine Brown Norway rats. Preretinal hemorrhage was induced bilaterally using diode laser focused deeply on choroidal blood vessels. One day later, AG3340 was injected intravitreally in the right eyes while the left eyes received equal amounts of vehicle. The developed epiretinal membrane was measured in disk areas and compared between groups.

RESULTS

Clinically, preretinal hemorrhage showed a slow clearance persisting for 8 to 10 weeks. ERM was well established around 12 weeks. Histologically, ERMs consist of fibroblast and glial cells embedded in collagen-rich extracellular matrix infiltrated by macrophages. Seventy-five percent of the hemorrhagic laser burns in the control group developed ERM, whereas only 25% of the hemorrhagic laser burns in treated group developed ERM (P = 0.01). The total surface area of developed ERM was 3.66 DD in treated eyes versus 25.45 DD in control eyes (P = 0.049). The mean surface area of ERM per eye was 0.52 disk areas +/- 1.05 in treated eyes versus 3.18 +/- 3.07 in control eyes.

CONCLUSION

We demonstrated that ERM can be induced on rat retina by simple hemorrhagic retinal laser coagulation. This new animal model could be used for future evaluation of different medical treatment modalities for proliferating ERM. Furthermore, AG3340 demonstrated an inhibitory effect on ERM formation in this new rat model.

Simultaneous measurement of MMP9 and TIMP1 mRNA in human non small cell lung cancers by multiplex real time RT-PCR

Extracellular matrix (ECM) homeostasis is strictly maintained by a coordinated balance between the expression of matrix metalloproteinases (MMPs) and their specific inhibitors (TIMPs). Our study was focused on the simultaneous measurement of the expression profile of MMP9 mRNA and its principal inhibitor, TIMP-1, in 100 non small cell lung cancers (NSCLC) and in corresponding adjacent non malignant tissues. The measurement was performed with a multiplex quantitative RT-PCR assay based on TaqMan assay, using two probes labelled with different fluorocromes. We found that both MMP9 and TIMP-1 mRNAs were significantly higher in NSCLC (P < 0.0001) in comparison to corresponding controls as well as the MMP9/TIMP-1 ratio (P = 0.014). MMP9 and TIMP-1 mRNA expression was highly correlated in cancer samples (r = 0.73, P < 0.0001). The analysis in the two main histotypes revealed a significant increase of MMP9 mRNA in adenocarcinomas in comparison to normal tissues (P = 0.006) but not in squamous cell carcinomas, while TIMP-1 mRNA showed a significative increase both in adenocarcinomas and in squamous cell carcinoma samples (P = 0.02 and 0.01, respectively). Both MMP9 and TIMP-1 mRNAs were significantly correlated to lymphnode invasion and cancer stage. Survival analysis revealed that high levels of expression of MMP9 mRNA, but not of TIMP-1, were significantly associated to an unfavourable outcome in NSCLC patients in toto (P = 0.017). In addition our results showed that high levels of MMP9 expression are of independent prognostic impact in operable NSCLC. Our data seem to demonstrate a simultaneous and coordinated up-regulation of MMP9 and TIMP-1 expression at the mRNA level in NSCLC, even if this phenomenon seems variable according to the histotype. In addition, the increase of MMP9/TIMP-1 ratio may reflect an unbalance of their production in affected tissues. The increased expression of the two mRNAs, even not necessarily equate their enzymatic activities, seems to parallel a major cancer aggressiveness.

A phase I and pharmacologic study of the matrix metalloproteinase inhibitor CP-471,358 in patients with advanced solid tumors

BACKGROUND

Matrix metalloproteinases play a role in the process of tissue invasion and metastasis by degrading the extracellular matrix. Inhibitors of matrix metalloproteinases are therefore of interest as anticancer drugs. CP-471,358 is a matrix metalloproteinase inhibitor that in vitro demonstrates strong inhibition of matrix metalloproteinases 2 and 9. The drug can be administered orally without food restriction.

STUDY DESIGN

An open-label phase I study was performed in patients with advanced solid tumors to assess the safety, tolerability, maximal tolerated dose (MTD) and pharmacokinetics of CP-471,358. The CP-471,358 doses studied were 50, 100 and 200 mg three times daily (TID) continuously, 50, 100 and 200 mg TID for 21 days followed by a 1-week treatment-free interval and 75 mg and 150 mg twice daily (BID) continuously.

RESULTS

A total of 38 patients were treated in the study. The median number of cycles administered was two (range one to five). Myalgia and arthralgia were the most frequently observed adverse events (in 27 of 38 patients) and were observed at all dose levels and with all schedules except for the 150 mg BID continuous dosing level. In six patients National Cancer Institute (NCI) Common Toxicity Criteria (CTC) grade 3 myalgia/arthralgia was observed and this adverse event was considered to be the dose-limiting toxicity (DLT). Introduction of a 1-week treatment-free interval between cycles had no effect on the occurrence of myalgia/arthralgia. After cessation of treatment, arthralgia/myalgia was reversible in all patients. Other adverse events observed were fatigue and an increase of liver enzymes but these rarely exceeded CTC grade 2. Pharmacokinetic analysis showed that target efficacious concentrations were achieved throughout the morning dosing interval with 150 mg BID and 200 mg TID.

CONCLUSION

The DLT of CP-471,358 was myalgia and arthralgia, an adverse event observed during treatment with most matrix metalloproteinase inhibitors. A drug-free interval of 1 week was unable to prevent the occurrence of these adverse effects. Clearly this represents a limitation for potential long-term use of this compound.

Phase I and pharmacokinetic study of prinomastat, a matrix metalloprotease inhibitor

PURPOSE

Prinomastat is a matrix metalloprotease (MMP) inhibitor with selectivity for MMPs 2, 3, 9, 13, and 14. Inhibition of these MMPs has been postulated to block tumor invasion and metastasis. This Phase I, dose-escalation study was designed to evaluate the acute and chronic toxicities of various doses of prinomastat and to determine prinomastat pharmacokinetics.

EXPERIMENTAL DESIGN

Seventy-five patients with advanced cancer were given 1, 2, 5, 10, 25, 50, or 100 mg prinomastat orally twice daily until tumor progression or development of significant toxicities. Prinomastat pharmacokinetics were measured on day 29 of therapy.

RESULTS

The primary toxicities identified were joint and muscle-related pain, which were generally reversible with treatment rest and/or dose reduction. No dose-limiting toxicities were noted within the first 4 weeks of treatment, but grade 2-3 arthralgias and myalgias were noted 2-3 months after initiation of therapy in >25% of patients at doses >25 mg twice a day. The frequency and severity of symptoms were dose related. Plasma prinomastat concentrations greater than the K(i) for MMPs 2 and 9 were achieved at all of the dose levels.

CONCLUSIONS

Doses of 5-10 mg bid were recommended for additional trials, because this dose range was well tolerated for a treatment duration of at least 3 months and achieves trough plasma concentrations 10-100-fold greater than the K(i) (in vitro inhibition constant) for the targeted MMPs (2 and 9).

Small cell lung cancer: the importance of the extracellular matrix

Lung cancer is the leading cause of cancer deaths in the UK and the small cell lung cancer (SCLC) phenotype is the most aggressive form of this disease, with a high metastatic potential and the development of resistance to chemotherapy. Evidence now suggests that these features may be due to important links between the cancer cells and proteins in their local extracellular matrix (ECM). This article reviews the evidence for a chemoprotective effect of extracellular matrix in small cell lung cancer and discusses the importance of integrin-mediated signalling pathways in this setting.

Mechanisms of and potential treatment strategies for metastatic disease in non-small cell lung cancer

Lung cancer consumes over one million lives in the world every year, with surgical resection playing a dominant role in the curative treatment of lung cancer with nonsmall cell histology. Mortality usually is the result of systemic spread of the disease, with little impact on survival when chemotherapy is applied in the adjuvant or palliative setting. Conventional cytotoxic chemotherapy has reached a plateau in efficacy. The future of treatment lies in the elucidation of the biology of lung cancer and the application of targeted therapies either alone or in combination with chemotherapy. The impact of the first generation of targeted therapies on lung cancer has been modest, with studies suggesting improvement in response rates, but no evidence of improved survival. As we expand our understanding of the mechanisms governing lung cancer progression and metastasis, we will be able to apply the growing armamentarium against this disease with a goal toward prolonging survival and increasing the chance for cure.

Blockade of the sympathetic nervous system degrades ligament in a rat MCL model

We hypothesize that blockade of the sympathetic nervous system degrades ligament. We tested this hypothesis in a rat medial collateral ligament (MCL) model. Fifteen animals were treated for 10 days with the sympathetic chemotoxin guanethidine using osmotic pumps, whereas 15 control rats received pumps containing saline. A reduction in plasma concentrations of norepinephrine in the guanethidine rats indicated a significant decrease in sympathetic nerve activity. Vasoactive intestinal peptide and neuropeptide Y were decreased in MCLs from guanethidine animals, as quantified by radioimmunoassays. Tissue vascularity was substantially increased in guanethidine MCLs, whereas mechanical properties were significantly decreased. Proteases, such as matrix metalloproteinases (MMP) and cysteine proteases, play a major role in ligament degradation. The proteases MMP-13, cathepsin K, and tartrate-resistant acid phosphatase (TRAP) have collagenolytic activity and have been shown in rat ligament tissues. To determine whether the degradation seen in this study was due to protease activity, we determined the expression of these enzymes in control and treated MCLs. Real-time quantitative PCR revealed that guanethidine treatment increased expression of MMP-13 and cathepsin K mRNAs, although overall expression levels of MMP-13 and TRAP were relatively low. Histology also identified increases in TRAP and cathepsin K, but not MMP-13, in guanethidine-treated tissues. Results support our hypothesis that blockade of the sympathetic nervous system substantially degrades ligament.

Emerging drugs for non-small cell lung cancer

Lung cancer is the leading cause of cancer death in the world. Therapeutic improvements caused by recent cytotoxic agents seem to have reached a plateau. New therapeutic strategies are, therefore, necessary to improve the cure rate. These include receptor-targeted therapy, signal transduction or cell-cycle inhibition, angiogenesis inhibitors, cyclooxygenase-2 (COX-2) inhibitors, gene therapy and vaccines. The antiepidermal growth factor receptor (EGFR) group includes compounds acting on the extracellular domain of EGFR, such as IMC-C225 and trastuzumab; small molecules inhibiting EGFR phosphorylation, such as ZD 1839 and OSI-774; or compounds that interfere with one of the downstream steps, such as mitogen-activated protein kinase kinase (MEK) inhibitors. Farnesyl transferase inhibitors, such as SCH66336, and protein kinase C inhibitors, such as ISIS 3521, have also shown antitumour activity. Antiangiogenesis inhibitors include matrix metalloprotease inhibitors (MMPIs), suchs as marimastat, AG3340, BAY 12-9566, BMS-275291 and Col-3. Antiangiogenic agents offer great potential for the treatment of lung cancer, as shown in preclinical models, whereas emerging data suggest that there are limits to their use as monotherapy in advanced disease. Molecules targeting vascular endothelial growth factor (VEGF) or its receptor (VEGFR) also seem to control tumour progression and may prolong survival. COX-2 inhibitors are another class of agents currently under evaluation in clinical trials for their chemoprevention role in subjects at high lung cancer risk, and also in patients with non-small cell lung cancer (NSCLC) in combination with standard chemotherapeutics. Genetic and immunologic therapies represent two additional promising modalities. All of these therapies are in different phases of clinical testing and have shown encouraging activity alone or in combination with chemotherapy drugs.