Inhibitor Of Cancer Cell Invasion Research Articles

Validated high-performance liquid chromatography method for the determination of the inhibitor of cancer cell invasion (E)-N-benzyl-6-[2-(3, 4-dihydroxy benzylidene)hydrazinyl]-N-methylpyridine-3-sulfonamide in rat plasma and its application to pharmacokinetic study.

In this study, a reliable method for the quantitation of (E)-N-benzyl-6-[2-(3, 4-dihydroxy benzylidene)hydrazinyl]-N-methylpyridine-3-sulfonamide (JW-55) in rat plasma was developed and validated using high-performance liquid chromatography. Plasma samples were deproteinized; sildenafil was used as an internal standard. Chromatographic separation was achieved using a reversed-phase C18 column. The mobile phase, 0.02 m ammonium acetate buffer:acetonitrile (48:52, v/v), was run at a flow rate of 1.0 mL/min at room temperature, and the column eluent was monitored using an ultraviolet detector at 280 nm. The retention times of JW-55 and sildenafil were ~5.9 and 7.7 min, respectively. The detection limit of JW-55 in rat plasma was 0.03 μg/mL. Pharmacokinetic parameters of JW-55 were evaluated after intravenous and oral administration of JW-55 (10 mg/kg) in rats. After oral administration, the F value was approximately 73.7%.

The natural product brartemicin is a high affinity ligand for the carbohydrate-recognition domain of the macrophage receptor mincle.

We demonstrate that the natural product brartemicin, a newly discovered inhibitor of cancer cell invasion, is a high-affinity ligand of the carbohydrate-recognition domain (CRD) of the C-type lectin mincle. Recent studies have revealed that mincle is a key macrophage receptor for the mycobacterial virulence factor trehalose dimycolate (TDM), which is a glycolipid component of the mycobacterial cell wall. Major uncertainties, however, remain concerning the mechanism of TDM-binding and subsequent signal transduction as well as interplay of potential co-receptors. Due to the lipid nature of TDM, functional studies are difficult and soluble mincle-ligands are therefore of significant interest. Brartemicin, together with designed analogs also presented in this paper, may thus serve as useful molecular probes for future studies of mincle. Through computational studies, we further provide an insight into the probable mode of binding of brartemicin.

Synthesis and biological studies of neopetrosiamides as inhibitors of cancer cell invasion

The tricyclic peptides neopetrosiamides A and B, isolated from the marine sponge Neopetrosia sp., are potential antimetastatic agents that inhibit tumour cell invasion by both amoeboid and mesenchymal migration pathways. They differ in the stereochemistry of the methionine sulfoxide at position 24. Our previously reported syntheses using an orthogonal sulfur protection strategy established the critical connectivity of the three disulfide bonds. In this report, fifteen analogues of neopetrosiamide A and B, six which replace selected disulfide bonds and nine which replace the diastereomeric methionine sulfoxide, have been prepared using Fmoc solid-phase peptide chemistry. Disulfide replacement analogues were shown to lose activity, and only one of the methionine sulfoxide analogues retained full bioactivity in morphological studies.

A Cell-Based High-Content Screening Assay Reveals Activators and Inhibitors of Cancer Cell Invasion

Acquisition of invasive cell behavior underlies tumor progression and metastasis. To further define the molecular mechanisms underlying invasive behavior, we developed a high-throughput screening strategy to quantitate invadopodia, which are actin-rich membrane protrusions of cancer cells that contribute to tissue invasion and matrix remodeling. We tested the LOPAC 1280 collection of pharmacologically active agents in a high-content, image-based assay and identified compounds that inhibited invadopodium formation without overt toxicity, as well as compounds that increased invadopodia number. The chemotherapeutic agent paclitaxel increased both the number of invadopodia and the invasive behavior of various human cancer cell lines, effects that have potential clinical implications for its use before surgical removal of a primary tumor (neoadjuvant therapy) or in patients with chemoresistant tumors. Several compounds that inhibited invasion have been characterized as cyclin-dependent kinase (Cdk) inhibitors, and loss-of-function experiments determined that Cdk5 was the relevant target. We further determined that Cdk5 promoted both invadopodium formation and cancer cell invasion by phosphorylating and thus decreasing the abundance of the actin regulatory protein caldesmon.

Abstract 3251: Characterization of a novel Rac inhibitor as an anti cancer metastasis compound

Abstract The objective of this project is to design novel therapeutics targeting cancer metastasis, the most deadly aspect of epithelial cancers. Our previous studies have shown that Rac, a key signaling intermediate that regulates actin cytoskeletal changes during cell migration/invasion and cancer metastasis, is associated with high cancer metastatic efficiency. Since Rac proteins are activated by GDP/GTP exchange, inhibition of the interaction of Rac with its guanine nucleotide exchange factors (GEF) is expected to inhibit Rac activity. Since the known Rac inhibitor NSC-23766 is not effective at therapeutically useful concentrations, we synthesized novel NSC-23766 derivatives. Results show that the new inhibitor EHop-016 is 100-fold more efficient than the parent compound at inhibiting Rac activity of metastatic cancer cells without affecting the activity of the related GTPase, Rho. EHop-016 inhibited Rac activity of metastatic cancer cells with an IC50 of 0.78 microM. Cell viability assays, performed to test for the toxicity of this compound, demonstrated that at concentrations below 5 microM, EHop-016 did not affect mammary epithelial cell (MCF-10A) viability and decreased proliferation of metastatic cancer cells (MDA-MB-435) by only 20%. We conclude that EHop-16 is a potent Rac inhibitor with promise of further development as a small molecule inhibitor of cancer cell invasion, and thus, metastasis. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3251. doi:10.1158/1538-7445.AM2011-3251

Comparison of Inhibitory Activities of Stereo-Isomers of Cyclic Phosphatidic Acid (cPA) on Autotaxin

Cyclic phosphatidic acid (cPA) has a similar structure to that of lysophosphatidic acid (LPA), but possesses distinct biological functions. For example, cPA suppresses cancer cell invasion and metastasis through the inhibition of autotaxin (ATX) and transient activation of low molecular weight GTPase, RhoA. We designed and chemically synthesized several metabolically stabilized derivatives of cPA, and revealed that 2-carba-cPA was the most potent inhibitor of cancer cell invasion and metastasis. We have developed a novel method of 2ccPA enantiomeric synthesis, and here we examined the effects of natural (R)-cPA, both enantiopure 2ccPA, and (S)-3ccPA (corresponding to the configuration of (R)-2ccPA) on ATX. We also predicted the effects of (R)-cPA, (R)-2ccPA and (S)-3ccPA on ATX activity by combined quantum mechanics and molecular mechanics (QM/MM) computational methods. By these methods, we demonstrated that 2ccPA was the most potent inhibitor on ATX, and the chirality of 2ccPA was not involved in ATX inhibition. These results suggest that racemic-2ccPA may be utilized as an effective compound for cancer therapeutics.

인체유방암세포의 tight junction 기능 조절을 통한 genistein의 암세포 침윤 억제 효과

Tight junctions (TJs) that act as paracellular permeability barriers play an essential role in regulating the diffusion of fluid, electrolytes and macromolecules through the paracellular pathway. In this study, we investigated the correlation between the tightening of TJs, permeability and the invasive activity of genistein - a bioactive isoflavone of soybeans - in human breast carcinoma MCF-7 and MDA-MB-231 cells. The inhibitory effects of genistein on cell proliferation, motility and invasiveness were found to be associated with the increased tightness of the TJs, which was demonstrated by an increase in transepithelial electrical resistance and a decrease in paracellular permeability. Additionally, the immunoblotting results indicated that genistein repressed the levels of the proteins that comprise the major components of TJ, claudin-3 and claudin-4, which play a key role in the control and selectivity of paracellular transport. Furthermore, genistein decreased the metastasis-related gene expressions of insulin like growth factor-1 receptor and snail, while concurrently increasing that of thrombospondin-1 and E-cadherin. In addition, we demonstrated that claudins play an important role in the anti-motility and invasiveness of genistein using claudin-3 small interfering RNA. Taken together, our results indicate a possible role for genistein as an inhibitor of cancer cell invasion through the tightening of TJs, which may counteract the up-regulation of claudins. In addition, our results indicate that this may be beneficial for the inhibition of tumor metastasis.

Strongylophorine-26, an Inhibitor of Cancer Cell Invasion: SAR Revealed by Synthesis of Analogues

The absolute configuration of strongylophorine-26 (1) was determined to be 4S, 5R, 8R, 9S, 10S, 13S, 14S by single-crystal X-ray diffraction analysis of the derivative 7 prepared from the co-occurring metabolite strongylophorine-8 (4) and chemical interconversion to the bislactone 8. Synthetic analogues (+)- and (-)-3 have been prepared in order to explore the structure-activity relationship for the anti-invasion pharmacophore of stronglylophorine-26. These studies revealed the unanticipated importance of the A ring lactone moiety for the anti-invasion activity of 1.

The invasive behaviour of prostatic cancer cells is suppressed by inhibitors of tyrosine kinase

Proteolytic enzymes, and especially urokinase plasminogen activator (uPA), play an important role in tumour invasion and metastasis. Previously we demonstrated that the production of urokinase plasminogen activator (uPA) was decreased by several tyrosine kinase inhibitors (TKI) in two prostatic carcinoma cell lines. The effect of the two TKI genistein and tyrphostin AG-1478 was investigated in the prostate carcinoma cell lines PC-3 and DU-145. A reconstituted basal lamina (Matrigel) was used as a migration barrier. The production of matrix metalloproteinases (MMP) was also measured. Roles of plasminogen and uPA were examined. Cell invasion was increased by plasminogen, but this enhanced cell migration was counteracted by TKI treatment. The increased cell invasion induced by plasminogen was decreased by at least 60% in both cell lines when alpha-2 anti-plasmin was added to the assay. Cells in the absence of plasminogen were not affected by TKI. External uPA failed to regenerate the decreased cell invasion caused by TKI. The production of MMP was inhibited by both TKI. Our results indicate a possible role of TKI as inhibitors of cancer cell invasion by inhibiting uPA and MMP production.

Strongylophorine-26, a Rho-dependent inhibitor of tumor cell invasion that reduces actin stress fibers and induces nonpolarized lamellipodial extensions

Strongylophorine-26, a new meroditerpenoid, was recently identified as an inhibitor of cancer cell invasion. This study was undertaken to characterize its mechanism of action. We find that strongylophorine-26 inhibits the motility of MDA-MB-231 breast carcinoma cells on a plastic surface. Upon addition of strongylophorine-26, rapid cell contraction and depolarization occurred, followed by spreading and flattening of the entire cell. Treated cells exhibited increased membrane ruffling throughout and extended lamellipodia in all directions. Strongylophorine-26 induced a decrease in actin stress fibers, a dramatic increase in the size and number of focal adhesions, and the appearance of a dense meshwork of actin filaments around the cell periphery. Strongylophorine-26 caused a transient activation of the small GTPase Rho and treatment with the Rho inhibitor C3 exoenzyme abrogated the anti-invasive activity of strongylophorine-26. These effects are distinct from those of many motility and angiogenesis inhibitors that seem to act by a common mechanism involving the induction of actin stress fibers. This difference in mechanism of action sets strongylophorine-26 apart as an experimental anticancer agent and indicates that pharmacologic inhibition of cell migration may be achieved by mechanisms not involving the stabilization of actin stress fibers.