Biomedical subjects

Luigi Strizzi

Publications and source records attributed to Luigi Strizzi.

17 recordsLinked to original sources

PubMed2006

Identification of cripto-1 as a novel serologic marker for breast and colon cancer.

PURPOSE: Human Cripto-1 (CR-1), a cell membrane glycosylphosphatidylinositol-anchored glycoprotein that can also be cleaved from the membrane, is expressed at high levels in several different types of human tumors. We evaluated whether CR-1 is present in the plasma of patients with breast and colon cancer, and if it can represent a new biomarker for these malignancies. EXPERIMENTAL DESIGN: We determined CR-1 plasma levels using a sandwich-type ELISA in 21 healthy volunteers, 54 patients with breast cancer, 33 patients with colon carcinoma, and 21 patients with benign breast lesions. Immunohistochemical analysis was also used to assess CR-1 expression in cancerous tissues. RESULTS: Very low levels of CR-1 (mean+/-SD) were detected in the plasma of healthy volunteers (0.32+/-0.19 ng/mL). A statistically significant increase in the levels of plasma CR-1 was found in patients with colon carcinoma (4.68+/-3.5 ng/mL) and in patients with breast carcinoma (2.97+/-1.48 ng/mL; P<0.001). Although moderate levels of plasma CR-1 were found in women with benign lesions of the breast (1.7+/-0.99 ng/mL), these levels were significantly lower than in patients with breast cancer (P<0.001). Finally, immunohistochemical analysis and real-time reverse transcription-PCR confirmed strong positivity for CR-1 in colon and/or breast tumor tissues. CONCLUSION: This study suggests that plasma CR-1 might represent a novel biomarker for the detection of breast and colon carcinomas.

Animals↗

PubMed2005

Epidermal growth factor receptor (EGFR) signaling in cancer.

The epidermal growth factor receptor (EGFR) belongs to the ErbB family of receptor tyrosine kinases (RTK). These trans-membrane proteins are activated following binding with peptide growth factors of the EGF-family of proteins. Evidence suggests that the EGFR is involved in the pathogenesis and progression of different carcinoma types. The EGFR and EGF-like peptides are often over-expressed in human carcinomas, and in vivo and in vitro studies have shown that these proteins are able to induce cell transformation. Amplification of the EGFR gene and mutations of the EGFR tyrosine kinase domain have been recently demonstrated to occur in carcinoma patients. Interestingly, both these genetic alterations of the EGFR are correlated with high probability to respond to anti-EGFR agents. However, ErbB proteins and their ligands form a complex system in which the interactions occurring between receptors and ligands affect the type and the duration of the intracellular signals that derive from receptor activation. In fact, proteins of the ErbB family form either homo- or hetero-dimers following ligand binding, each dimer showing different affinity for ligands and different signaling properties. In this regard, evidence suggests that cooperation of multiple ErbB receptors and cognate ligands is necessary to induce cell transformation. In particular, the growth and the survival of carcinoma cells appear to be sustained by a network of receptors/ligands of the ErbB family. This phenomenon is also important for therapeutic approaches, since the response to anti-EGFR agents might depend on the total level of expression of ErbB receptors and ligands in tumor cells.

Animals↗

PubMed2005

Netrin-1 regulates invasion and migration of mouse mammary epithelial cells overexpressing Cripto-1 in vitro and in vivo.

The neuronal guidance molecule, Netrin-1, has been suggested to play a role in the adhesion and migration of the mammary gland epithelium. Human and mouse Cripto-1 induce proliferation, migration, invasion and colony formation by epithelial cells in 3D matrices. Here we investigate whether Netrin-1 affects these Cripto-1-dependent activities in mouse mammary epithelial cells. Overexpression of Cripto-1 in EpH4 and HC-11 cells (EpH4/Cripto-1 or HC-11/Cripto-1) was associated with low expression of Netrin-1 and increased expression of its receptor Neogenin compared to that of wild-type cells. No change was observed in the expression of the other Netrin-1 receptor, UNC5H1. Treating EpH4/Cripto-1 or HC-11/Cripto-1 mammary cells with exogenous soluble Netrin-1 resulted in increased expression of E-cadherin and UNC5H1, decreased expression of vimentin and decreased activation of Akt as determined by western blotting. Colony formation by Eph4/Cripto-1 cells in 3D gels was significantly reduced in proximity to a Netrin-1 source, and mammary glands of transgenic mice overexpressing human Cripto-1 showed altered ductal growth in proximity to implanted Netrin-1-releasing pellets. Terminal end buds in the treated transgenic mice mammary glands also showed increased expression of E-cadherin and UNC5H1 and decreased expression of active Akt determined by immunohistochemistry. Together, these results suggest that regulation of Netrin-1 expression is important in regulating Cripto-1-dependent invasion and migration of mammary epithelial cells.

Animals↗

PubMed2005

Modulation of TGF-beta signaling by EGF-CFC proteins.

Members of the transforming growth factor-beta (TGF-beta) family of ligands exhibit potent growth-suppressive and/or apoptosis-inducing effects on different types of cells. They perform essential roles in the elimination of damaged or abnormal cells from healthy tissues. On the other hand, TGF-betas have also been shown to act as tumor-promoting cytokines in a number of malignancies that are capable of stimulating extracellular matrix production, cell migration, invasion, angiogenesis, and immune suppression. Dissecting the complex, multifaceted roles of different TGF-beta-related peptides especially during the development of pathological conditions and in carcinogenesis is an area of continuous research and development. The characterization of EGF-CFC proteins as essential co-receptors that contribute to the modulation of the physiological activities of some of the TGF-beta ligands will be beneficial for future medical research and the adaptation and possible readjustment of currently applied therapeutic regimes.

Animals↗

PubMed2005

Cripto-1: a multifunctional modulator during embryogenesis and oncogenesis.

It is increasingly evident that genes known to perform critical roles during early embryogenesis, particularly during stem cell renewal, pluripotentiality and survival, are also expressed during the development of cancer. In this regard, oncogenesis may be considered as the recapitulation of embryogenesis in an inappropriate temporal and spatial manner. The epidermal growth factor-Cripto-1/FRL1/cryptic family of proteins consists of extracellular and cell-associated proteins that have been identified in several vertebrate species. During early embryogenesis, epidermal growth factor-Cripto-1/FRL1/cryptic proteins perform an obligatory role as coreceptors for the transforming growth factor-beta subfamily of proteins, which includes Nodal. Cripto-1 has also been shown to function as a ligand through a Nodal/Alk4-independent signaling pathway that involves binding to glypican-1 and the subsequent activation through src of phosphoinositol-3 kinase/Akt and ras/mitogen-activated protein kinase intracellular pathways. Expression of Cripto-1 is increased in several human cancers and its overexpression is associated with the development of mammary tumors in mice. Here, we review the role of Cripto-1 during embryogenesis, cell migration, invasion and angiogenesis and how these activities may relate to cellular transformation and tumorigenesis. We also briefly discuss evidence suggesting that Cripto-1 may be involved in stem cell maintenance.

Activin Receptors, Type I↗

PubMed2005

Notch4 intracellular domain binding to Smad3 and inhibition of the TGF-beta signaling.

We present evidence that Notch4ICD attenuates TGF-beta signaling. Cells expressing the activated form of the Notch4 receptor (ICD4) were resistant to the growth-inhibitory effects of TGF-beta. Notch4ICD was found to bind to Smad2, Smad3 and Smad4 but with higher affinity to Smad3. Deletion analysis showed that binding of Smad3 to ICD4 was mediated by its MH2 domain and was not dependent on the presence of the RAM23 region in ICD4. Using two TGF-beta/Activin reporter luciferase assays, RT-PCR and Western blot analysis, we demonstrate that ICD4 and ICD4 deltaRAM23 inhibit Smad-binding element and 3TP luciferase reporter activity and PAI-1 gene expression. MCF-7 human breast cancer cells express Notch4ICD (ICD4) and are resistant to the growth-inhibitory effects of TGF-beta. Blockage of Notch4 processing to ICD4 by gamma-secretase inhibitor renders MCF-7 cells sensitive to growth inhibition by TGF-beta. The interplay between these two signaling pathways may be a significant determinant during mammary tumorigenesis.

Amino Acid Motifs↗

PubMed2005

Human Cripto-1 overexpression in the mouse mammary gland results in the development of hyperplasia and adenocarcinoma.

Human Cripto-1 (CR-1) is overexpressed in approximately 80% of human breast, colon and lung carcinomas. Mouse Cr-1 upregulation is also observed in a number of transgenic (Tg) mouse mammary tumors. To determine whether CR-1 can alter mammary gland development and/or may contribute to tumorigenesis in vivo, we have generated Tg mouse lines that express human CR-1 under the transcriptional control of the mouse mammary tumor virus (MMTV). Stable Tg MMTV/CR-1 FVB/N lines expressing different levels of CR-1 were analysed. Virgin female MMTV/CR-1 Tg mice exhibited enhanced ductal branching, dilated ducts, intraductal hyperplasia, hyperplastic alveolar nodules and condensation of the mammary stroma. Virgin aged MMTV/CR-1 Tg mice also possessed persistent end buds. In aged multiparous MMTV/CR-1 mice, the hyperplastic phenotype was most pronounced with multifocal hyperplasias. In the highest CR-1-expressing subline, G4, 38% (12/31) of the multiparous animals aged 12-20 months developed hyperplasias and approximately 33% (11/31) developed papillary adenocarcinomas. The long latency period suggests that additional genetic alterations are required to facilitate mammary tumor formation in conjunction with CR-1. This is the first in vivo study that shows hyperplasia and tumor growth in CR-1-overexpressing animals.

Adenocarcinoma↗

PubMed2005

Role of human cripto-1 in tumor angiogenesis.

BACKGROUND: Human cripto-1 (CR-1) promotes cell transformation and increases migration and invasion of various mouse and human epithelial cell lines. We investigated whether CR-1 also stimulates angiogenesis. METHODS: We used human umbilical vein endothelial cells (HUVECs) to measure in vitro migration with fibronectin-coated Boyden chambers, invasion with Matrigel-coated Boyden chambers, proliferation with a tetrazolium salt, and differentiation with an in vitro Matrigel assay. We investigated new blood vessel formation in vivo by use of Matrigel-filled silicone cylinders implanted under the skin of nude mice and by use of a breast cancer xenograft model with CR-1-transfected or control Neo-transfected MCF-7 human breast cancer cells. We also used a blocking anti-CR-1 monoclonal antibody to investigate the role of CR-1 in angiogenesis in vivo and in vitro. All statistical tests were two-sided. RESULTS: CR-1 stimulated HUVEC proliferation, migration, and invasion and induced HUVEC differentiation into vascular-like structures on Matrigel. In vivo, recombinant CR-1 protein induced microvessel formation in Matrigel-filled silicone cylinders, and microvessel formation was statistically significantly inhibited with a blocking anti-CR-1 monoclonal antibody (CR-1 and antibody = 127% of microvessel formation compared with that in untreated control cylinders and CR-1 alone = 259%; difference = 132%, 95% confidence interval [CI] = 123% to 140%; P<.001). Tumors formed by CR-1-transfected MCF-7 cells in the cleared mammary fat pad of nude mice had higher microvessel density than tumors formed by control Neo-transfected MCF-7 cells (CR-1-transfected cells = 4.66 vessels per field and Neo-transfected cells = 2.33 vessels per field; difference = 2.33 vessels per field, 95% CI = 1.2 to 2.8; P = .004). CONCLUSION: CR-1 appears to have an important role in the multistep process of angiogenesis.

Animals↗

PubMed2005

Overexpression of human Cripto-1 in transgenic mice delays mammary gland development and differentiation and induces mammary tumorigenesis.

Overexpression of Cripto-1 has been reported in several types of human cancers including breast cancer. To investigate the role of human Cripto-1 (CR-1) in mammary gland development and tumorigenesis, we developed transgenic mice that express the human CR-1 transgene under the regulation of the whey acidic protein (WAP) promoter in the FVB/N mouse background. The CR-1 transgene was detected in the mammary gland of 15-week-old virgin WAP-CR-1 female mice that eventually developed hyperplastic lesions. From mid-pregnancy to early lactation, mammary lobulo-alveolar structures in WAP-CR-1 mice were less differentiated and delayed in their development due to decreased cell proliferation as compared to FVB/N mice. Early involution, due to increased apoptosis, was observed in the mammary glands of WAP-CR-1 mice. Higher levels of phosphorylated AKT and MAPK were detected in mammary glands of multiparous WAP-CR-1 mice as compared to multiparous FVB/N mice suggesting increased cell proliferation and survival of the transgenic mammary gland. In addition, more than half (15 of 29) of the WAP-CR-1 multiparous female mice developed multifocal mammary tumors of mixed histological subtypes. These results demonstrate that overexpression of CR-1 during pregnancy and lactation can lead to alterations in mammary gland development and to production of mammary tumors in multiparous mice.

Animals↗

PubMed2005

Cripto-1: an oncofetal gene with many faces.

Human Cripto-1 (CR-1), a member of the epidermal growth factor (EGF)-CFC family, has been implicated in embryogenesis and in carcinogenesis. During early vertebrate development, CR-1 functions as a co-receptor for Nodal, a transforming growth factor beta (TGFbeta) family member and is essential for mesoderm and endoderm formation and anterior-posterior and left-right axis establishment. In adult tissues, CR-1 is expressed at a low level in all stages of mammary gland development and expression increases during pregnancy and lactation. Overexpression of CR-1 in mouse mammary epithelial cells leads to their transformation in vitro and, when injected into mammary glands, produces ductal hyperplasias. CR-1 can also enhance migration, invasion, branching morphogenesis and epithelial to mesenchymal transition (EMT) of several mouse mammary epithelial cell lines. Furthermore, transgenic mouse studies have shown that overexpression of a human CR-1 transgene in the mammary gland under the transcriptional control of the mouse mammary tumor virus (MMTV) promoter results in mammary hyperplasias and papillary adenocarcinomas. Finally, CR-1 is expressed at high levels in approximately 50 to 80% of different types of human carcinomas, including breast, cervix, colon, stomach, pancreas, lung, ovary, and testis. In conclusion, EGF-CFC proteins play dual roles as embryonic pattern formation genes and as oncogenes. While during embryogenesis EGF-CFC proteins perform specific and regulatory functions related to cell and tissue patterning, inappropriate expression of these molecules in adult tissues can lead to cellular proliferation and transformation and therefore may be important in the etiology and/or progression of cancer.

Epidermal Growth Factor↗

PubMed2004

Cripto-1 overexpression leads to enhanced invasiveness and resistance to anoikis in human MCF-7 breast cancer cells.

Cripto-1 (CR-1) is an epidermal growth factor (EGF)-CFC protein that has been shown to signal through nodal/Alk-4, PI3K/Akt, and/or ras/raf/MEK/MAPK pathways in mammalian cells, and that is frequently expressed in human primary breast carcinomas. In the present study, the human estrogen receptor positive, MCF-7 breast cancer cell line, that expresses low levels of endogenous CR-1, was transfected with a CR-1 expression vector. MCF-7 CR-1 cells expressed high levels of a 25 kDa recombinant CR-1 protein that was not detected in MCF-7 cells transfected with a control vector (MCF-7 neo). Overexpression of CR-1 did not induce an estrogen independent phenotype in MCF-7 cells. In fact, MCF-7 CR-1 cells showed a response to exogenous estrogens that was similar to MCF-7 neo cells, and failed to grow in immunosuppressed mice in absence of estrogen stimulation. However, MCF-7 CR-1 cells showed a rate of proliferation in serum free conditions, and an ability to form colonies in soft-agar that were higher as compared with MCF-7 neo cells. More importantly, overexpression of CR-1 enhanced the resistance to anoikis and the invasion ability of MCF-7 cells. MCF-7 CR-1 cells showed levels of activation of both Akt and Smad-2 that were significantly higher as compared with MCF-7 neo. These findings suggest that CR-1 overexpression might be associated with the progression towards a more aggressive phenotype in breast carcinoma, through the activation of both Akt and Smad-2 signalling pathways.

Animals↗

PubMed2004

Epithelial mesenchymal transition is a characteristic of hyperplasias and tumors in mammary gland from MMTV-Cripto-1 transgenic mice.

Epithelial-mesenchymal transition (EMT) facilitates migration and invasion of epithelial tumor cells. Cripto-1 (CR-1), a member of the epidermal growth factor-CFC protein family increases migration of cells in vitro. Here the expression of molecular markers and signaling molecules characteristic of EMT were assessed in mammary gland hyperplasias and tumors from mice expressing the human CR-1 transgene by the MMTV promoter (MMTV-CR-1) and in mouse mammary epithelial cell line HC-11 overexpressing CR-1 (HC-11/CR-1). Western blot analysis showed decreased expression of E-cadherin in MMTV-CR-1 tumors and in HC-11/CR-1 cells. The expression of N-cadherin, vimentin, cyclin-D1, and of the zinc-finger transcription factor, snail, was increased in MMTV-CR-1 tumors. Increased snail mRNA was also found in HC-11/CR-1 cells. Expression of phosphorylated (P)-c-Src, P-focal adhesion kinase (FAK), P-Akt, P-glycogen synthease kinase 3beta (GSK-3beta), dephosphorylated (DP)-beta-catenin, and various integrins such as, alpha 3, alpha v, beta 1, beta 3, and beta 4 was also increased in MMTV-CR-1 tumors. Immunohistochemistry showed positive staining for vimentin, N-cadherin, cyclin-D1, smooth muscle actin, fibronectin, snail, and beta-catenin in MMTV-CR-1 tumor sections. HC-11/CR-1 cells treated with the c-Src inhibitor PP2 reduced the expression of P-c-Src and of P-FAK, P-Akt, P-GSK-3beta, DP-beta-catenin all known to be activated by c-Src. Migration of HC-11/CR-1 cells was also reduced by PP2 treatment. These results suggest that CR-1 may play a significant role in promoting the increased expression of markers and signaling molecules associated with EMT.

Animals↗

PubMed2004

CRIPTO-1: a novel target for therapeutic intervention in human carcinoma.

Evidence suggests that CRIPTO-1 (CR-1) might be involved in the pathogenesis of human carcinoma. In the present study, we have screened the expression of CR-1 mRNA and protein in a wide panel of human cancer cell lines by using reverse transcriptase (RT)-PCR, real-time PCR and immunocytochemistry. Results of these experiments demonstrate that CR-1 is expressed in several, different carcinoma types. The anchorage-independent growth of colon, ovarian, lung and breast carcinoma cells was significantly inhibited by treatment with anti-CR-1 second generation antisense oligonucleotides. Similar results were obtained with anti-transforming growth factor alpha (TGF-alpha) and anti-amphiregulin (AR) antisense oligonucleotides. Treatment of carcinoma cells with CR-1 antisense oligonucleotides resulted in a significant reduction in the levels of expression of CR-1 mRNA and protein, and in the levels of activation of Akt. Finally, oral administration of either CR-1, AR or TGF-alpha antisense oligonucleotides produced a significant reduction in the growth of GEO colon carcinoma xenografts in nude mice that was associated with a reduction in the levels of expression of the target proteins. Taken together, these data strongly suggest that CR-1 might represent a novel target for therapeutic intervention in different carcinoma types.

Amphiregulin↗

PubMed2003

A Nodal- and ALK4-independent signaling pathway activated by Cripto-1 through Glypican-1 and c-Src.

Human Cripto-1 (CR-1) is a member of the epidermal growth factor-Cripto FRL1 Cryptic family that has been shown to function as a coreceptor with the type I Activin serine-threonine kinase receptor ALK4 for the transforming growth factor beta-related peptide Nodal. However, CR-1 can also activate the mitogen-activated protein kinase and Akt pathways independently of Nodal and ALK4 by an unknown mechanism. Here, we demonstrate that CR-1 specifically binds to Glypican-1, a membrane-associated heparan sulfate proteoglycan, and activates the tyrosine kinase c-Src, triggering the mitogen-activated protein kinase and Akt signaling pathways. Finally, an active Src kinase is necessary for CR-1 to induce in vitro transformation and migration in mouse mammary epithelial cells.

Activin Receptors, Type I↗

PubMed2003

Transforming growth factor-beta released by PPD-presenting malignant mesothelioma cells inhibits interferon-gamma synthesis by an anti-PPD CD4+ T-cell clone.

Besides acting complexly on both normal and tumor cells, transforming growth factor-beta (TGF-beta) can determine the nature of the response to the antigen, strongly inhibiting the differentiation of naive CD4+ T-cells toward a T helper-1 (Th-1) phenotype; in a number of experimental models, TGF-beta also appeared to be a potent immunosuppressant factor. TGF-beta was shown to be released by some human malignant mesothelioma (MMe) cells, which affects the immune response to this tumor. Thus, for a better understanding of the role of TGF-beta in the immune response to MMe cells, we evaluated the production of a Th-1 cytokine (IFN-gamma) and of a Th-2 cytokine (IL-4), following Purified Protein Derivative (PPD) recall antigen presentation by human MMe cells to a class-II major histocompatibility complex (MHC-II)-matched PPD clone (PPD clone). Our data confirm that human MMe cells possess the unusual capability of presenting a common recall antigen to CD4+ lymphocytes but also show that these tumor cells can abrogate Th-1 immune response, as evidenced by a shift in favor of the production of IL-4 over that of IFN-gamma, through a TGF-beta-mediated pathway; only the simultaneous block of TGF-beta1 and beta2 effects can significantly restore a typical Th-1 pattern of cytokine production by PPD clone in response to PPD presentation by MMe. Even though the role of TGF-beta in the promotion of MMe growth should be further and better defined, this effect should be considered when designing new therapeutical approaches aimed at improving the immune response to MMe.

CD4-Positive T-Lymphocytes↗

PubMed2002

The presence of simian-virus 40 sequences in mesothelioma and mesothelial cells is associated with high levels of vascular endothelial growth factor.

The aim of this study was to evaluate whether the presence of simian virus-40 (SV40) is associated with increased release of vascular endothelial growth factor (VEGF) in human malignant mesothelioma (MM) cells. We studied nine cell lines derived from pleural effusion (PE) of patients with MM, and three different cultures of normal human mesothelial cells (NHMC) derived from pleural fluid of patients with congestive heart failure. NHMC were transfected with full length SV40 (NHMC-FL) or large T antigen (NHMC Tag) DNAs. High levels of VEGF were detected in conditioned media of each of two MM cells that tested positive for SV40 by PCR amplification and Southern blot hybridization and for Tag transcript by reverse transcription- polymerase chain reaction (RT-PCR) and immunoprecipitation. We also found that NHMC-FL released high amounts of VEGF. Conditioned media from SV40-positive MM cells and from FL-NHMC increased proliferation of human umbilical vein cells (HUVEC) and this effect was partially abrogated by adding specific blocking antibodies against VEGF. These results offer the first evidence that SV40 can cause VEGF release in SV40-positive MM cells and that entire viral genome is required for this effect.

Antigens, Polyomavirus Transforming↗

PubMedDate not supplied

Neutralizing antibodies against endogenous interferon in myasthenia gravis patients.

Anti-cytokine antibodies (Abs) play an important role in the regulation of the immune response, both under normal conditions and in several autoimmune and neoplastic disorders. In the present study, we have investigated the occurrence and the clinical significance of natural neutralizing Abs (NAbs) against interferons (IFNs) alpha, beta, and gamma, as detected by bioassay, in 52 patients with myasthenia gravis (MG), and 43 sex- and age-matched healthy individuals. Patients showing titres > or = 1.3 Log t(1/10), confirmed in 2 consecutive samples collected two months apart, were considered positive. NAbs against any of the IFNs were not detected in healthy subjects. Of the 52 MG patients, 11 (21.1%) had NAbs against IFNalpha and three (5.8%) had NAbs against IFNbeta. None of these patients was found to be positive for NAbs against IFNgamma. Of the patients positive for NAbs against IFNalpha, eight (15.4%) had NAbs at titres > or =2 Log t(1/10). A positive association was observed between high titres of NAbs and the presence of thymoma. These data suggest the presence of a generalized activation of the humoral response in MG.

Adult↗