RAGE/SNAIL1 signaling drives epithelial-mesenchymal plasticity in metastatic triple-negative breast cancer.

Epithelial/Mesenchymal (E/M) plasticity plays a fundamental role both in embryogenesis and during tumorigenesis. The receptor for advanced glycation end products (RAGE) is a driver of cell plasticity in fibrotic diseases; however, its role and molecular mechanism in triple-negative breast cancer (TNBC) remains unclear. Here, we demonstrate that RAGE signaling maintains the mesenchymal phenotype of aggressive TNBC cells by enforcing the expression of SNAIL1.

AlO:Yb integrated microdisk laser label-free biosensor.

Whispering gallery mode resonator lasers hold the promise of an ultralow intrinsic limit of detection. However, the widespread use of these devices for biosensing applications has been hindered by the complexity and lack of robustness of the proposed configurations. In this work, we demonstrate biosensing with an integrated microdisk laser.

AlO microring resonators for the detection of a cancer biomarker in undiluted urine.

Concentrations down to 3 nM of the rhS100A4 protein, associated with human tumor development, have been detected in undiluted urine using an integrated sensor based on microring resonators in the emerging AlO photonic platform. The fabricated microrings were designed for operation in the C-band (λ = 1565 nm) and exhibited a high-quality factor in air of 3.2 × 10.

Site-Specific Antibody Drug Conjugates Using Streamlined Expressed Protein Ligation.

Antibody-Drug Conjugates (ADCs) have been shown to produce clinical benefit in cancer patient thanks to their ability to target highly cytotoxic small molecules to tumor cells. However, the development of these complex molecules faces significant challenges due to the need to combine a large biologic drug with a small molecule drug to generate the desired bioconjugate. We describe here the use of a protein ligation methodology, based on the native chemical ligation reaction to generate site-specific Antibody-Drug Conjugates, which does not require the incorporation of unnatural modifications into the antibody.

Toward Angiogenesis Inhibitors Based on the Conjugation of Organometallic Platinum(II) Complexes to RGD Peptides.

A novel conjugate between a cyclometalated platinum(II) complex with dual antiangiogenic and antitumor activity and a cyclic peptide containing the RGD sequence (-Arg-Gly-Asp-) has been synthesized by combining solid- and solution-phase methodologies. Although peptide conjugation rendered a non-cytotoxic compound in all tested tumor cell lines (± α β and α β integrin receptors), the antiangiogenic activity of the Pt-c(RGDfK) conjugate in human umbilical vein endothelial cells at sub-cytotoxic concentrations opens the way to the design of a novel class of angiogenesis inhibitors through conjugation of metallodrugs with high antiangiogenic activity to cyclic RGD-containing peptides or peptidomimetic analogues.

S100A7: from mechanism to cancer therapy.

Within the tumor, malignant and stromal cells support each other by secreting a wide variety of growth factors and cytokines, allowing tumor growth and disease progression. The identification and regulation of those key factors in this crosstalk has opened the opportunity to develop new therapeutic strategies that not only act on the tumor cells but also on the stroma. Among these factors, S100A7 protein has gained interest in the last years.

S100P antibody-mediated therapy as a new promising strategy for the treatment of pancreatic cancer.

Despite progresses in diagnosis and treatment, pancreatic cancer continues to have the worst prognosis of all solid malignant tumors. Recent evidences suggest that the metastasis-promoting protein S100P stimulates pancreatic tumor proliferation, survival, invasion and metastasis progression through extracellular functions. Moreover, its expression is strongly correlated with poor prognosis in patients with several types of cancer although the entire molecular mechanism responsible for the diverse biological functions is not fully understood.

Tackling lipophilicity of peptide drugs: replacement of the backbone N-methyl group of cilengitide by N-oligoethylene glycol (N-OEG) chains.

Cilengitide is an RGD-peptide of sequence cyclo[RGDfNMeV] that was was developed as a highly active and selective ligand for the αvβ3 and αvβ5 integrin receptors. We describe the synthesis of three analogues of this peptide in which the N-Me group has been replaced by N-oligoethylene glycol (N-OEG) chains of increasing size: namely N-OEG2, N-OEG11, and N-OEG23, which are respectively composed of 2, 11, and 23 ethylene oxide monomer units. The different N-OEG cyclopeptides and the original peptide were compared with respect to lipophilicity and biological activity.

Micropattern of antibodies imaged by shear force microscopy: comparison between classical and jumping modes.

Quartz tuning fork devices are increasingly being used as nanosensors in Scanning Probe Microscopy. They offer some benefits with respect to standard microfabricated cantilevers in certain experimental setups including the study of biomolecules under physiological conditions. In this work, we compare three different working modes for imaging micropatterned antibodies with quartz tuning fork sensors: apart from the classical amplitude and frequency modulation strategies, for first time the jumping mode is implemented using tuning forks.

Therapeutic targeting of tumor growth and angiogenesis with a novel anti-S100A4 monoclonal antibody.

S100A4, a member of the S100 calcium-binding protein family secreted by tumor and stromal cells, supports tumorigenesis by stimulating angiogenesis. We demonstrated that S100A4 synergizes with vascular endothelial growth factor (VEGF), via the RAGE receptor, in promoting endothelial cell migration by increasing KDR expression and MMP-9 activity. In vivo overexpression of S100A4 led to a significant increase in tumor growth and vascularization in a human melanoma xenograft M21 model.

The backbone N-(4-azidobutyl) linker for the preparation of peptide chimera.

A robust synthetic strategy for the introduction of the N-(4-azidobutyl) linker into peptides using standard SPPS techniques is described. Based on the example of Cilengitide it is shown that the N-(4-azidobutyl) group exerts similar conformational restraints as a backbone N-Me group and allows conjugation of a desired molecule either via click chemistry or-after azide reduction-via acylation or reductive alkylation.

Synthesis and biological evaluation of novel indolocarbazoles with anti-angiogenic activity.

A novel series of indolocarbazoles were synthesized and their antiproliferative activity against HUVEC, LoVo, DLD-1 and ST-486 cell lines, was investigated. Those staurosporine analogs in which a substituted dimethylaminoalkoxy chain was attached to the indolic nitrogen showed interesting activity and selectivity with respect to HUVEC proliferation. The effect on capillary tube formation in 3-dimensional matrigel matrix was studied using the most active compounds.

Dual effects of β3 integrin subunit expression on human pancreatic cancer models.

Background: Pancreatic cancer, the fifth leading cause of adult cancer death in Western countries, lacks early detection, and displays significant dissemination ability. Accumulating evidence shows that integrin-mediated cell attachment to the extracellular matrix induces phenotypes and signaling pathways that regulate tumor cell growth and migration.

Methods: In view of these findings, we examined the role of β(3) in pancreatic cancer by generating two stable β(3)-expressing pancreatic human cell lines and characterizing their behavior in vitro and in vivo.

Dual effects of β3 integrin subunit expression on human pancreatic cancer models.

Background: pancreatic cancer, the fifth leading cause of adult cancer death in Western countries, lacks early detection, and displays significant dissemination ability. Accumulating evidence shows that integrin-mediated cell attachment to the extracellular matrix induces phenotypes and signaling pathways that regulate tumor cell growth and migration.

Methods: in view of these findings, we examined the role of β3 in pancreatic cancer by generating two stable β3-expressing pancreatic human cell lines and characterizing their behavior in vitro and in vivo.

Inhibition of human immunodeficiency virus type 1 infection in macrophages by an alpha-v integrin blocking antibody.

Macrophages are key cells for HIV infection and HIV spreading inside the organism. Macrophages cultured in vitro can be successfully infected after differentiation with cytokines such as macrophage colony stimulating factor (M-CSF). In the monocyte to macrophage differentiation process with M-CSF, alphav-integrins are upregulated concomitantly with the capacity of HIV to generate a productive virus infection.

Anti-migratory and anti-angiogenic effect of p16: a novel localization at membrane ruffles and lamellipodia in endothelial cells.

Recent evidence has established different functions for the tumor suppressor protein, p16(INK4A) aside from controlling the cell cycle. Here we report that cdk4/6 inhibition blocked both human umbilical vein endothelial cells (HUVEC) spreading on a vitronectin matrix and HUVEC migration on vitronectin. p16 can also act as an anti-angiogenic molecule in vitro since HUVEC and HMEC cells transfected with Ad-p16 or treated with Antennapedia p16 peptides are unable to differentiate on a Matrigel matrix.

Alphavbeta5-integrins mediate early steps of metastasis formation.

Tumour cell adhesion within the microvasculature of host organs, its stabilisation and cell invasion into the host organs, appear to be important steps in the formation of distant metastases. Intravital fluorescence-video microscopy was used to investigate the early steps in metastasis formation of colon carcinoma cells within the liver, which is the main target organ of colorectal carcinomas. The involvement of alphav-integrins was analysed in vivo using HT-29 cells after treatment with different function-blocking antibodies [pan-alphav (n=9 animals), specific alphavbeta3 (n=8 animals) and alphavbeta5 (n=8 animals)] or linear Arg-Gly-Asp (RGD)-containing peptides (RGD-peptides) (n=6 animals).

Use of siRNAs and antisense oligonucleotides against survivin RNA to inhibit steps leading to tumor angiogenesis.

The antiapoptotic protein survivin is an attractive target in cancer therapy because it is expressed differently in tumors and normal tissues and it is potentially required for cancer cells to remain viable. Given that survivin is also overexpressed in endothelial cells (ECs) of newly formed blood vessels found in tumors, its RNA targeting might compromise EC viability and interfere with tumor angiogenesis. We used two antisense strategies against survivin expression, antisense oligonucleotides (aODN) and small interfering RNA (siRNA), to study in ECs the contribution of survivin in various steps leading to tumor angiogenesis.

Leukocyte recruitment in colon cancer: role of cell adhesion molecules, nitric oxide, and transforming growth factor beta1.

Background & Aims: A deficient leukocyte recruitment has been suggested in tumor vasculature, but little is known about the underlying molecular mechanism. To characterize leukocyte-endothelium interaction in experimental colon cancer, quantify the main endothelial cell adhesion molecules (CAMs), and evaluate the effect of tumor-derived products.

Methods: Leukocyte recruitment was assessed by intravital videomicroscopy in mice bearing HT29-derived tumors.

RGD peptides and monoclonal antibodies, antagonists of alpha(v)-integrin, enter the cells by independent endocytic pathways.

Cyclic synthetic peptides containing the arginine-glycine-aspartate motif (cRGD) and monoclonal antibodies (mAbs) targeted for individual integrins have been developed as potential therapeutic drugs for the treatment of several diseases. We showed that a cRGD peptide targeted for alpha(v)beta(3) was internalized in alpha(v)-integrin expressing and nonexpressing melanoma cells by an integrin independent fluid-phase endocytosis pathway that does not alter the number of functional integrin receptors at the cell surface. In contrast, a blocking mAb directed to alpha(v) was internalized by an integrin-dependent endocytosis pathway that reduced the number of functional integrin receptors at the cell surface.

Synthesis and biological evaluation of novel bisindolylmaleimides that inhibit vascular endothelial cell proliferation.

A novel class of bisindolylmaleimides were synthesized and antiproliferative activities (HUVECs and three tumor cell lines) of these compounds were investigated. Two water-soluble derivatives, 10 and 12, possessing a dimethylaminoalkoxy side chain in their structure, showed interesting activity and selectivity on HUVECs proliferation.

Alpha v integrin antagonists induce the disassembly of focal contacts in melanoma cells.

In recent years, several antagonists of alpha(v)beta3 have been used to develop therapeutic approaches to the treatment of melanoma neoplasia. We studied the effects of anti-alpha(v)-integrin-blocking antibodies on attached M21 melanoma cells, the cellular distribution of alpha(v)-integrin and the molecular organization of focal structures. Anti-alpha(v)-integrin-blocking antibodies 17E6 and LM609, and an anti-alpha(v)beta3-integrin antagonist peptide cRGD 85189 induced detachment of M21 melanoma cells cultured for 24 hours on various substrates.

In vivo therapy of malignant melanoma by means of antagonists of alphav integrins.

Integrin alphavbeta3 (vitronectin receptor) has been implicated in human malignant melanoma progression and angiogenesis as a receptor that provides survival signals. However, little is known about the therapeutic potential of antagonists of alphavbeta3. In this report, we characterize the activities of 2 antagonists of alphavbeta3 integrins: a human specific monoclonal antibody (MAb), 17E6, and a cyclic RGD peptide that blocked cell adhesion and induced detachment of previously substrate-attached cells in vitro.

Integrin alpha(v)beta3 promotes M21 melanoma growth in human skin by regulating tumor cell survival.

Growth and dissemination of malignant melanoma has a profound impact on our population, and little is known concerning the mechanisms controlling this disease in humans. Evidence is provided that integrin alpha(v)beta3 plays a critical role in M21 melanoma tumor survival within human skin by a mechanism independent of its known role in angiogenesis. Antagonists of alpha(v)beta3 blocked melanoma growth by inducing tumor apoptosis.