Colorectal cancer (CRC) results from the accumulation of both genetic and epigenetic alterations of the genome. However, also the formation of an inflammatory milieu plays a pivotal role in tumor development and progression. Dendritic cells (DCs) play a relevant role in tumor by exerting differential pro-tumorigenic and anti-tumorigenic functions, depending on the local milieu.
View Article and Find Full Text PDFZoledronic acid has shown indirect anticancer effects on angiogenesis, the tumor microenvironment and immune responses. Its immunological action is exerted, at least in part, via its modulating properties. The aim of this study was to investigate the in vitro effects of zoledronic acid on the dendritic cells of melanoma patients.
View Article and Find Full Text PDFWe evaluated the promoter methylation levels of the APC, MGMT, hMLH1, RASSF1A and CDKN2A genes in 107 colorectal cancer (CRC) samples and 80 healthy adjacent tissues. We searched for correlation with both physical and pathological features, polymorphisms of folate metabolism pathway genes (MTHFR, MTRR, MTR, RFC1, TYMS, and DNMT3B), and data on circulating folate, vitamin B12 and homocysteine, which were available in a subgroup of the CRC patients. An increased number of methylated samples were found in CRC respect to adjacent healthy tissues, with the exception of APC, which was also frequently methylated in healthy colonic mucosa.
View Article and Find Full Text PDFThe aim of this work was to assess the impact on measurements of methylation of a panel of four cancer gene promoters of purifying tumor cells from colorectal tissue samples using the epithelial cell adhesion molecule (EpCAM)-immunomagnetic cell enrichment approach. We observed that, on average, methylation levels were higher in enriched cell fractions than in the whole tissue, but the difference was significant only for one out of four studied genes. In addition, there were strong correlations between methylation values for individual samples of whole tissue and the corresponding enriched cell fractions.
View Article and Find Full Text PDFColorectal cancer (CRC) is the second-leading cause of cancer-related deaths in Western countries. Today, the role of the host's immune system in controlling the progression and spread of solid tumors is broadly established. Tumor immunosurveillance escape mechanisms, such as those involving dendritic cells (DCs), the most important antigen-presenting cells, are likewise recognized processes involved in cancer.
View Article and Find Full Text PDFColorectal cancer is a malignancy with poor prognosis that might be associated with defective immune function. The aim of the present study was to investigate circulating dendritic cells in colorectal cancer patients, in order to contribute to elucidate tumor-escape mechanisms and to point out a possible correlation with the clinical condition of the disease. Therefore, we enumerated ex vivo myeloid and plasmacytoid dendritic cells, through multicolor flow cytometry, in 26 colorectal patients and 33 healthy controls.
View Article and Find Full Text PDFThe behaviour of circulating dendritic cells (DCs) and DC generation from monocytes in melanoma patients during the progression of disease have not been described. We report a significant decrease in the absolute number of total DCs, which mainly affects plasmacytoid DCs in stage IV. Additionally, monocyte-DC generation is less efficient in advanced stages, resulting in DCs that exhibit increased phagocytic capacity, potentially indicating a less mature state.
View Article and Find Full Text PDFAdjuvant therapy in colorectal cancer has evolved to become the standard of care, whereas the tumor capability of activating effective mechanisms of defence against both chemical and physical cytotoxic agents represents a serious obstacle to the successful therapy of human tumors. Therefore, the possibility to have an assay useful to measure the drug sensitivity of tumor cells has a great importance. A number of cytotoxicity assays are currently available, each of them using a specific approach to detect different aspects of cell viability, such as cell integrity, proliferation and metabolic functions.
View Article and Find Full Text PDFThere is increasing interest in the development of cost-effective techniques for the quantification of DNA methylation biomarkers. We analyzed 90 samples of surgically resected colorectal cancer tissues for APC and CDKN2A promoter methylation using methylation sensitive-high resolution melting (MS-HRM) and pyrosequencing. MS-HRM is a less expensive technique compared with pyrosequencing but is usually more limited because it gives a range of methylation estimates rather than a single value.
View Article and Find Full Text PDFMore than a million people a year worldwide develops colorectal cancer (CRC), with a mortality rate close to 33%. Most of the CRC cases are sporadic, only 25% of the patients have a family history of the disease, and major genes causing syndromes predisposing to CRC only account for 5-6% of the total cases. The following subtypes can be recognized: MIN (microsatellite instability), CIN (chromosomal instability), and CIMP (CpG island methylator phenotype).
View Article and Find Full Text PDFHuman aging is associated with immunosenescence, a process characterized by alterations in numerical and functional features of immune system components. Dendritic cells (DCs) are the main antigen-presenting cells, playing a pivotal role in adaptive and innate immunity. Therefore, we investigated the distribution of human circulating DCs throughout the life, in order to contribute to the knowledge of the physiological background underlying the aging of immune system.
View Article and Find Full Text PDFAdjuvant therapy has evolved to become the standard care of colon cancer, but the tumor capability of activating effective mechanisms of defence against both chemical and physical cytotoxic agents represents a serious obstacle to the successful therapy. Furthermore, the possibility to have an assay useful to measure the drug sensitivity of tumor cells could be of a great importance. As primary human colon cancer cultures from fresh tumor are technically difficult to obtain, experiments with human cancer cell lines remain essential to explore new adjuvant chemotherapy drugs, to investigate the individual responsiveness to the known agents, and particularly to clarify how these chemotherapeutic agents could be used in maximizing outcomes.
View Article and Find Full Text PDFExp Biol Med (Maywood)
December 2011
Zoledronic acid (ZA) is a drug of the bisphosphonate class, which is widely used for the treatment of both osteoporosis and skeletal metastasis. Besides its main bone antiresorptive activity, ZA displays antitumor properties, by triggering the expansion and activation of γδ T-cells, which exert an antitumor effect through dendritic cells (DCs). Several studies have reported the interaction between ZA and γδ T-cells, but the potential immunoregulatory activity of this drug on DCs has scarcely been investigated.
View Article and Find Full Text PDFThe functional properties of myeloid dendritic cells (DCs) differ, depending on microenvironmental factors as well as on their stage of maturation. The main approaches for the selective enhancement of the tolerogenic properties of DCs include the induction of a pharmacological arrest of the DCs maturation and the genetical engineering of DCs expressing immunosuppressive molecules. Several immunosuppressive/anti-inflammatory agents have been discovered that potentially inhibit DC maturation and immunogenicity.
View Article and Find Full Text PDFA series of biaryl amides containing an azabicyclooctane amine headpiece were synthesized and evaluated as mixed arginine vasopressin (AVP) receptor antagonists. Several analogues, including 8g, 12g, 13d, and 13g, were shown to have excellent V(1a)- and good V(2)-receptor binding affinities. Compound 13d was further profiled for drug-like properties and for an in vitro comparison with conivaptan, the program's mixed V(1a)/V(2)-receptor antagonist standard.
View Article and Find Full Text PDFBackground: Setting of cellular cultures extracted from colorectal cancer tissue represents a valid model for in vitro study of biological and molecular characteristics of each single tumor finalized to obtain a tailored chemiotherapy. The end point of this study is to create primary cellular cultures from "fresh" cancer tissue in different stages of evolution.
Methods: Cancer tissue samples are obtained by means of surgical excisional biopsy or by means of semi-automatic biopsy instrument (Sprig-Cut).
On the basis of the previously reported clinical candidate, SSA-426 (1), a series of related 2-piperazin-1-ylquinoline derivatives 3-16 were synthesized and evaluated as dual-acting serotonin (5-HT) reuptake inhibitors and 5-HT1A receptor antagonists. In particular, compound 7 exhibits potent functional activities at both the 5-HT transporter and 5-HT1A receptor, good selectivity over the alpha1-adrenergic and dopaminergic receptors, acceptable pharmacokinetic properties, and a favorable in vivo profile.
View Article and Find Full Text PDFBackground: Because colorectal cancer is a significant cause of morbidity and mortality in the Western population, knowledge of the molecular and biological alterations associated with its development is important. Since primary human colon cancer cultures from fresh tumor tissue are technically difficult to obtain, experiments in most laboratories are performed on colon epithelial cell lines, but these represent just one stage of tumor progression. Only primary cultures of neoplastic colonocytes may reflect the actual responsiveness of tumors at certain developmental stages to antitumor agents.
View Article and Find Full Text PDFA 23-member library of pyrrolobenzodiazepine derivatives with vasopressin agonist activity was purified on a 100-mg per injection scale using normal-phase (NP) automated mass-directed HPLC. Analytical NP APCI-LC/MS on an experimental monolith silica CN column utilizing gradients of methanol in ethoxynonafluorobutane (hexane-like solvent) was used to provide data on chromatographic purity and ionization of the solutes. The analytical data collected were used to program a preparative LC/MS instrument for "smart" fraction collection based on the protonated molecular ion of the component of interest.
View Article and Find Full Text PDFExtracorporeal photopheresis (ECP) has been considered an efficient dendritic cell (DC) therapy, used for treating both T cell malignancy, as well as T cell-mediated diseases. During the ECP procedure leucocytes are exposed to photoactivable agent 8-methoxypsolaren (8-MOP) and ultraviolet (UV) A radiation (PUVA) prior to reinfusion. Despite its clinical efficacy the mechanism of action remains elusive.
View Article and Find Full Text PDFA series of pyrazolidine-3,5-dione and 5-hydroxy-1H-pyrazol-3(2H)-one inhibitors of Escherichia coli UDP-N-acetylenolpyruvyl glucosamine reductase (MurB) has been prepared. The 5-hydroxy-1H-pyrazol-3(2H)-ones show low micromolar IC(50) values versus E. coli MurB and submicromolar minimal inhibitory concentrations (MIC) against Staphylococcus aureus GC 1131, Enterococcus faecalis GC 2242, Streptococcus pneumoniae GC 1894, and E.
View Article and Find Full Text PDFA series of 3,5-dioxopyrazolidines was identified as novel inhibitors of UDP-N-acetylenolpyruvylglucosamine reductase (MurB). Compounds 1 to 3, which are 1,2-bis(4-chlorophenyl)-3,5-dioxopyrazolidine-4-carboxamides, inhibited Escherichia coli MurB, Staphyloccocus aureus MurB, and E. coli MurA with 50% inhibitory concentrations (IC50s) in the range of 4.
View Article and Find Full Text PDFAcyl carrier protein synthase (AcpS) catalyzes the transfer of the 4'-phosphopantetheinyl group from the coenzyme A to a serine residue in acyl carrier protein (ACP), thereby activating ACP, an important step in cell wall biosynthesis. The structure-based design of novel anthranilic acid inhibitors of AcpS, a potential antibacterial target, is presented. An initial high-throughput screening lead and numerous analogues were modeled into the available AcpS X-ray structure, opportunities for synthetic modification were identified, and an iterative process of synthetic modification, X-ray complex structure determination with AcpS, biological testing, and further modeling ultimately led to potent inhibitors of the enzyme.
View Article and Find Full Text PDFOur efforts in seeking low molecular weight agonists of the antidiuretic peptide hormone arginine vasopressin (AVP) have led to the identification of the clinical candidate WAY-151932 (VNA-932). Further exploration of the structural requirements for agonist activity has provided another class of potent, orally active, non-peptidic vasopressin V2 receptor selective agonists exemplified by the 5,11-dihydro-pyrido[2,3-b][1,5]benzodiazepine as a candidate for further development.
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