carbocyanines and Stomach-Neoplasms

Claudin 18.2 (CLDN18.2) is a new potential target for cancer therapy, especially for advanced gastric cancer (AGC). A molecular targeting probe is of importance for patient stratification and therapeutic guidance. Here, we explored an antibody-dependent molecular imaging strategy for specific detection and surgery guidance based on a CLDN18.2-specific antibody, 5C9. Two imaging probes,

Topics: Carbocyanines; Cell Adhesion Molecules; Cell Line, Tumor; Claudins; Humans; Immunoglobulin G; Iodine Radioisotopes; Stomach Neoplasms

Leucine-rich repeat-containing G-protein coupled receptor 5 (LGR5) is a stem cell marker in gastric cancer. In this study, we aimed to produce the LGR5-targeting peptide probe for the use of molecular imaging for gastric cancer. We used phage display libraries to produce a LGR5-specific peptide probe. This peptide was validated for targeting gastric cancer with in vitro and in vivo studies. This peptide was tagged with fluorescein isothiocyanate (FITC) and cyanine 5.5 (Cy5.5). We used two normal and three gastric cancer cell lines. Immunocytochemistry (ICC) and fluorescence-activated cell sorting (FACS) analysis were used to validate the target specificity of the peptide. After three rounds of bio-panning, we found a novel 7-mer peptides, IPQILSI (IPQ∗). FITC-conjugated IPQ∗ showed 2 to 10 times higher fluorescence in gastric cancer cells vs. control cells in ICC. This discrimination was consistently observed using Cy5.5-conjugated IPQ∗ in ICC. FACS analysis showed right shift of peak point in gastric cancers compared to the control cells. In the peritoneal metastasis animal model, we could find Cy5.5-conjugated IPQ∗ accumulated specifically to gastric tumors. In conclusion, IPQ∗ peptide showed a specific probe for gastric cancer diagnosis. This probe can be applied to theragnosis for gastric cancer diagnosis including peritoneal metastasis.

Topics: Animals; Carbocyanines; Cell Line, Tumor; Fluorescein-5-isothiocyanate; Fluorescent Dyes; Humans; Mice, Nude; Molecular Imaging; Optical Imaging; Peptides; Receptors, G-Protein-Coupled; Stomach Neoplasms

Topics: Adenocarcinoma; Animals; Carbocyanines; Cell Line, Tumor; Disease Models, Animal; Ferrosoferric Oxide; Fluorescent Dyes; Humans; Injections, Subcutaneous; Magnetic Resonance Imaging; Magnetite Nanoparticles; Male; Mice; Mice, Nude; Molecular Probes; Neovascularization, Pathologic; Optical Imaging; Peptides, Cyclic; Polyethylene Glycols; Stomach Neoplasms

Near-infrared fluorescence (NIRF) imaging agents are promising tools for noninvasive cancer imaging. Here, we explored the tumor-specific targeting ability of NIRF heptamethine carbocyanine MHI-148 dye in cultured gastric cancer cells, gastric cancer cell-derived and patient-derived tumor xenograft (PDX) models. We show that the NIRF dye specifically accumulated in tumor regions of both xenograft models, suggesting the potential utility of the dye for tumor-specific imaging and targeting in gastric cancer. We also demonstrated significant correlations between NIRF signal intensity and tumor volume in PDX models. Mechanistically, the higher cellular uptake of MHI-148 in gastric cancer cells than in normal cells was stimulated by hypoxia and activation of a group of organic anion-transporting polypeptide (OATP) genes. Importantly, this NIRF dye was not retained in inflammatory stomach tissues induced by gastric ulcer in mice. In addition, fresh clinical gastric tumor specimens, when perfused with NIR dye, exhibited increased uptake of NIR dye in situ. Together, these results show the possibility of using NIRF dyes as novel candidate agents for clinical imaging and detection of gastric cancer.

Topics: Animals; Carbocyanines; Cell Line, Tumor; Fluorescence; Fluorescent Dyes; Humans; Hypoxia-Inducible Factor 1, alpha Subunit; Inflammation; Male; Mice; Mice, Inbred BALB C; Mice, Nude; Microscopy, Fluorescence; Neoplasm Transplantation; Optical Imaging; Stomach Neoplasms

Gastric carcinoma is the most malignant tumor. Due to lacking of efficient means to diagnose the cancer at the early stage, it is necessary to develop effective molecular probes for early diagnosis and treatment. We have selected aptamers with high specificity and affinity against SGC7901 cells by cell-SELEX (Systematic Evolution of Ligands by Exponential Enrichment) method, which shown important clinical applications: (1) Specific recognize human gastric tumor tissues compared to the normal tissues. (2)When used to capture cancerous cells, the aptamer-functionalized fluorescent-magnetic nanospheres (FMNS) could specifically capture 93% target cancer cells and about 70% target cells can be released. (3) The aptamer probe displayed a quenched fluorescence in the absence of target cancer cells and went through a conformational transformation upon binding to target cancer cells that induced fluorescence. (4) The aptamer probe could target gastric tumors transplanted into mice with obvious fluorescence. The newly generated aptamers hold great potential in early cancer diagnosis.

Topics: Animals; Aptamers, Nucleotide; Carbocyanines; Cell Line; Cell Line, Tumor; Fluorescence; Fluorescent Dyes; Gastric Mucosa; Humans; Magnetic Phenomena; Male; Mice; Mice, Nude; Nanospheres; SELEX Aptamer Technique; Stomach Neoplasms

We describe a near-infrared-sensitive molecular imaging probe based on hydrogel complexes that can target a stem-like gastric cancer cell marker (CD44, a marker that often correlates with a poor prognosis in patients). Thus, CD44-targetable and near-infrared-sensitive supramolecular hydrogels (NIRSHs, Cy5.5-conjugated polyethyleneimine/hyaluronic acid polyplexes) were fabricated by polyplexing in an aqueous medium. NIRSHs demonstrated good water-stability, biocompatibility, and specificity to CD44-expressing stem-like gastric cancer cells. Furthermore, NIR-sensitive in vivo imaging potentials of CD44-targetable NIRSHs for heterotopic/orthotopic xenograft mouse models were investigated.

Topics: Animals; Carbocyanines; Cell Line, Tumor; Cell Tracking; Fluorescent Dyes; Hyaluronan Receptors; Hydrogels; Macromolecular Substances; Mice; Mice, Inbred BALB C; Microscopy, Fluorescence; Molecular Imaging; Neoplastic Stem Cells; Spectroscopy, Near-Infrared; Stomach Neoplasms

To facilitate the translation of cancer fluorescence imaging into clinical practice, the development of stable and highly specific and sensitive targeted fluorescence probes with low toxicity is desirable. GX1, a gastric tumor angiogenesis marker candidate, holds promise in the target-specific delivery of molecular imaging probes for early gastric cancer detection in vivo. In this study, we describe the design and synthesis of a series of novel penta-methine cyanine dyes using the symmetric synthesis method and further conjugated the dyes with GX1, allowing specific binding to the vasculature of gastric cancer. This efficient synthetic route can decrease the undesired byproducts, while increasing yield. Furthermore, in vivo fluorescence imaging revealed that this novel targeted probe accumulates selectively in the tumor site of SGC-7901 subcutaneous xenograft models. The combination of such novel vasculature-targeted molecular probes with fluorescence imaging technology may improve early detection, metastasis detection, and antitumor angiogenesis therapy for gastric cancer.

Topics: Carbocyanines; Cells, Cultured; Coloring Agents; Humans; Magnetic Resonance Spectroscopy; Mass Spectrometry; Microscopy, Fluorescence; Molecular Probes; Peptides; Stomach Neoplasms

Near-infrared (NIR) fluorescence optical imaging is an emerging imaging technique for studying diseases at the molecular level. Optical imaging with a NIR emitting fluorophore for targeting tumor vasculature offers a noninvasive method for early detection of tumor angiogenesis and efficient monitoring of response to anti-tumor vasculature therapy. The previous in vitro results demonstrated that the GX1 peptide, identified by phage-display technology, is a tumor vasculature endothelium-specific ligand. In this report, Cy5.5-conjugated GX1 peptide was evaluated in a subcutaneous U87MG glioblastoma xenograft model to investigate tumor-targeting efficacy. The in vitro flow cytometry results revealed dose-dependent binding of Cy5.5-GX1 peptide to U87MG glioma cells. In vivo optical imaging with the Cy5.5-GX1 probe exhibited rapid U87MG tumor targeting at 0.5 h p.i., and high tumor-to-background contrast at 4 h p.i. Tumor specificity of Cy5.5-GX1 was confirmed by effective blocking of tumor uptake in the presence of unlabeled GX1 peptide (20 mg/kg). Ex vivo imaging further confirmed in vivo imaging findings, and demonstrated that Cy5.5-GX1 has a tumor-to-muscle ratio (15.21 ± 0.84) at 24 h p.i. for the non-blocked group and significantly decreased ratio (6.95 ± 0.75) for the blocked group. In conclusion, our studies suggest that Cy5.5-GX1 is a promising molecular probe for optical imaging of tumor vasculature.

Topics: Animals; Bacteriophages; Carbocyanines; Cell Line, Tumor; Female; Fluorescent Dyes; Humans; Mice; Mice, Nude; Molecular Imaging; Molecular Probes; Neovascularization, Pathologic; Peptide Library; Peptides; Spectrometry, Fluorescence; Spectroscopy, Near-Infrared; Stomach; Stomach Neoplasms

Gastric cancer is the second most common fatal malignancy in the world. Proteomics studies of clinical tumor samples have led to the identification of specific protein markers of gastric cancer detection and better understanding the carcinogenesis of gastric cancer. Gastric cancer tissue of epithelial origin and adjacent normal mucosa were examined in pair by fluorescence 2-D differential in-gel electrophoresis proteomics analysis utilizing 2-D PAGE protein separation. Intensity changes of 33 spots were detected with statistical significance. Twenty-two out of the 33 spots were identified by MALDI-TOF MS or MS/MS. Of the 9 up-regulated proteins, 7 were identified, including heat shock protein 60 (HSP60), mutant desmin, effector cell proteinase receptor 1 splice form 1b, hypothetical protein, unnamed protein product, and manganese superoxide dismutase (MnSOD), a protein similar to alpha-actin. Of the 20 down-regulated proteins, 16 were identified, including selenium binding protein 1, fibrinogen gamma, HSP27, tubulin alpha 6, zinc finger protein 160, prostaglandin F synthase, and eukaryotic translation elongation factor 1 alpha 1. Our results suggest that MnSOD may be a potential serum marker for molecular diagnosis of gastric carcinoma, and DIGE is a useful technique for screening differentially expressed proteins in cancer tissues.

Topics: Aged; Aged, 80 and over; Biomarkers, Tumor; Biopsy; Carbocyanines; Electrophoresis, Gel, Two-Dimensional; Female; Fluorescent Dyes; Humans; Male; Middle Aged; Neoplasm Proteins; Neoplasm Staging; Proteomics; Spectrometry, Fluorescence; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Stomach Neoplasms; Tandem Mass Spectrometry

Stem cell transplantation offers potential gene therapy for brain tumors. However, this approach has received little attention as a treatment for gastrointestinal tumors. In the present study, we explored the possibility of human bone marrow-derived mesenchymal stem cells (hMSC) producing cytosine deaminase (CD), followed by systemic 5-fluorocytosine (5-FC) administration, showing an antitumor effect on a mouse gastric cancer xenograft.. We first explored the ability of hMSC, coated with fluorescent dye, to migrate to human gastric cancer MKN45 cells in vitro and in vivo. We then used hMSC in which a gene expressed the prodrug-activating enzyme CD, which can convert the prodrug 5-FC into the cytotoxic agent 5-fluorouracil (5-FU), and further investigated the potential of these cells to deliver the CD gene and to reduce tumor growth in nude mice. The migratory capacity of hMSC was confirmed by an in vitro migration assay, as well as in an in vivo model of nude mice bearing subcutaneous tumors of MKN45 cells when hMSC were injected.. The migration ability of hMSC towards MKN45 cells was confirmed by migration assay. Effective conversion of 5-FC to 5-FU by hMSC transfected with the CD gene (CD-hMSC) showed therapeutic anticancer potential in a MKN45 cell co-culture system, as confirmed by thin layer chromatography. Nude mice bearing MKN45 tumors were intravenously injected with CD-hMSC, followed by systemic 5-FC treatment (500 mg/kg/day) for 7 days. Tumor volumes and weights of mice injected with CD-hMSC decreased significantly after treatment with 5-FC. However, the 5-FC-treated group without CD-hMSC injection showed neither a decrease in tumor volume nor bodyweight loss.. The CD-hMSC system showed anticancer therapeutic potential, and minimized the side-effects of 5-FU.

Topics: Animals; Antimetabolites, Antineoplastic; Carbocyanines; Cell Line, Tumor; Cell Movement; Cytosine Deaminase; Dose-Response Relationship, Drug; Escherichia coli Proteins; Female; Flucytosine; Fluorescent Dyes; Fluorouracil; Humans; Injections, Intraperitoneal; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Mice; Mice, Nude; Microscopy, Fluorescence; NIH 3T3 Cells; Prodrugs; Stomach Neoplasms; Time Factors; Transfection; Xenograft Model Antitumor Assays

To study the effects of LY294002, an inhibitor of class I phosphatidylinositol 3-kinase (PI3K), on proliferation and apoptosis of SGC7901 gastric cancer cells.. The MTT assay was used to determine the cytotoxic effects of LY294002. Cell cycle distribution was analyzed using flow cytometry and apoptosis was assessed using flow cytometry analysis after staining DNA with propidium iodide. Mitochondrial membrane potential was measured using the fluorescent probe JC-1. Expression of p53 and PUMA was determined using real-time RT-PCR and Western blotting analysis.. The viability of SGC7901 cells was significantly reduced by LY294002 treatment. Expression of p53 and PUMA was induced, and mitochondrial membrane potential collapsed after treatment with LY294002. LY294002 induced apoptotic cell death.. Activation of the p53 pathway is involved in LY294002-induced SGC7901 cell death.

Topics: Apoptosis; Benzimidazoles; Carbocyanines; Cell Line, Tumor; Cell Survival; Chromones; Dose-Response Relationship, Drug; Enzyme Inhibitors; Fluorescent Dyes; Formazans; Humans; Membrane Potential, Mitochondrial; Morpholines; Phosphoinositide-3 Kinase Inhibitors; Stomach Neoplasms; Tetrazolium Salts; Time Factors; Tumor Suppressor Protein p53

Laser capture microdissection (LCM) provides the capability to isolate and analyze small numbers of cells from a specific area of a histologic section. LCM has particular value for analysis of early stage tumors, which are often small and intermixed with non-tumor tissue. It has previously been shown that a new generation of cysteine-reactive cyanine dyes can, in principle, provide increased sensitivity for two-dimensional fluorescence difference gel electrophoresis (2-D DIGE) profiling when sample quantitities are limiting. However, the comparative advantage of the new dyes in a clinical setting has not been established. Here, we report that cysteine-reactive dyes allowed the identification of more features than established, lysine-reactive dyes with a given number of cells. This was true both with extracts prepared from human papillomavirus E6 and E7-transduced human keratinocytes, a model for early-stage cervical cancer, and with LCM samples. In an experiment comparing LCM clinical samples of gastric adenocarcinoma versus precancerous, spasmolytic polypeptide expressing metaplasia (SPEM) from the same patient, cysteine labeling allowed the identification of more than 1000 discrete protein spots in samples containing 5000 cells. This is a 5- to 50-fold smaller sample than used in previous studies. Both labeling methods had a comparable success rate for protein identification by mass spectrometry (MS). The proteins associated with more than 40 differentially abundant spots in the clinical samples were identified by MS. In this exploratory analysis, changes in expression levels of cytoskeletal proteins, molecular chaperones, and cell-signaling proteins were seen. The identification of a number of proteins that are potentially relevant to tumor progression suggests that the method holds promise for biomarker discovery.

Topics: Adenocarcinoma; Biomarkers; Carbocyanines; Cells, Cultured; Cysteine; Fluorescent Dyes; Humans; Keratinocytes; Lasers; Microdissection; Proteomics; Staining and Labeling; Stomach Neoplasms