agar and Stomach-Neoplasms

Topics: Agar; Amino Acid Sequence; Animals; Buffers; Carcinoma; Cathepsins; Chemical Phenomena; Chemistry; Chromium Isotopes; Dietary Proteins; Duodenum; Electrophoresis; Enzyme Precursors; Gastric Juice; Gels; Humans; Hydrochloric Acid; Hydrogen-Ion Concentration; Molecular Weight; Pepsin A; Stomach; Stomach Neoplasms; Stomach Ulcer; Swine; Terminology as Topic

Rapid urease tests (RUTs) are used commonly as a convenient method to detect Helicobacter pylori infection. New rapid tests have been commercially available with promotional literature suggesting enhanced utility. We compared CLOtest to a new reagent strip RUT, PyloriTek.. Gastric antral mucosal biopsy specimens were obtained from 102 patients for comparison between CLOtest and PyloriTek (204 specimens). Biopsy specimens obtained from a nearby area were stained using the Genta stain for determination of H. pylori status. The RUT to be used first was selected randomly.. Sixty-five of the 102 patients had peptic ulcer disease, two had gastric cancer, and 35 had dyspepsia; 61 patients had active H. pylori infection. There were one false-negative and three false-positive CLOtest results, compared with one false-negative and 13 false-positive PyloriTek results (p < 0.02 for incorrect categorization with PyloriTek). Sensitivity and specificity were 98 and 92% compared with 98 and 68% for CLOtest and PyloriTek, respectively. An erroneous categorization of H. pylori status occurred in 3.9% (95% confidence interval [CI]: 1-9.7%) with CLOtest compared with 13.7% (95% CI: 7.7 -22%) with PyloriTek. When the PyloriTek was scored at 1 h (0-1 h) after obtaining the specimen, the accuracy improved; erroneous categorization of H. pylori status occurred in only 2.9% (95% CI: 0.6-8.3%).. Used according to manufacturer instructions, the new reagent strip RUT PyloriTek has too many false-positive results for use in a clinical situation. In contrast, when the test was interpreted within 1 h, accuracy was comparable to that of CLOtest.

Topics: Adult; Agar; Aged; Biopsy; Coloring Agents; Confidence Intervals; Dyspepsia; False Negative Reactions; False Positive Reactions; Female; Gastric Mucosa; Gastroesophageal Reflux; Helicobacter Infections; Helicobacter pylori; Humans; Male; Middle Aged; Peptic Ulcer; Prospective Studies; Pyloric Antrum; Reagent Strips; Sensitivity and Specificity; Stomach Neoplasms; Urease

We report a case of canine adenocarcinoma with multi-organ metastasis in which colonies of adenocarcinoma cells grew upon aerobic bacterial culture of pleural effusion. Stained agar colonies were highly similar to rare suspicious cells seen on cytologic examination of the pleural effusion, as well as rare cells seen on cytologic examination of pancreatic and gastric wall fine-needle aspirates. Cells from colonies growing on agar media were mildly immunoreactive for cytokeratin. Histologic examination of tissues obtained at autopsy revealed pancreatic adenocarcinoma with vascular invasion and nodal, gastric, pulmonary, and pleural metastasis.

Topics: Adenocarcinoma; Agar; Animals; Bacteriological Techniques; Biopsy, Fine-Needle; Culture Media; Dog Diseases; Dogs; Female; Lung; Lung Neoplasms; Lymphatic Metastasis; Pancreatic Neoplasms; Pleural Effusion, Malignant; Pleural Neoplasms; Stomach Neoplasms

Procedure of endoscopic submucosal dissection (ESD) has been introduced widely for treatment of early gastric cancers. For such specimens, accurate pathological diagnosis, especially concerning depth of the invasion and exposure to margins, is essential to decide on the necessity of additional treatment. Therefore, easy and reliable tissue-processing method for multiple cut specimens is needed. The authors report here a new double embedding technique for specimens of ESD.. Formalin-fixed whole specimen was superficially wrapped by agarose (the first embedding), and the tissue-agarose block was cut at 2-3 mm intervals. Each cut specimen was laid down with 90° rotation. This procedure permitted 'on edge' embedding of thin tissues in paraffin (the second embedding) and subsequent preparation of perpendicular section to the tissue surface. The authors compared the handleability and stainability among several media including various types of agar, agarose and gelatin for first embedding. A survey by questionnaire was carried out on handleability and/or impression on various tissue-processing steps from pathology technicians.. Among the media examined, agarose showed the best solubility in water and the best transparency on several representative stainings. According to the survey, pathology technicians seemed to feel that the present method was better than the usual tissue processing method, especially in shortened time consumption and accuracy of alignment of multiple tissues for ESD specimens.. The present new double embedding technique using agarose provides not only an easy and reliable embedding procedure for technicians but also accurate and exact diagnosis for pathologists.

Topics: Agar; Dissection; Formaldehyde; Gastroscopy; Gelatin; Humans; Paraffin Embedding; Sepharose; Staining and Labeling; Stomach Neoplasms; Tissue Embedding

Ribosomal proteins are the components of ribosome, which also exhibit various secondary functions in DNA repair, apoptosis, drug resistance and proliferation. In our previous study of microarray, ribosomal protein L15 (RPL15) was identified as an upregulated gene in gastric cancer.. We investigated the expression of ribosomal protein L15 in gastric cancer and the effect of RPL15 on proliferation of gastric cancer.. It was found that the expression of RPL15 was markedly up-regulated in gastric cancer tissues. RPL15 was also highly expressed in gastric cancer cell lines AGS, MKN45, MKN28, SGC7901 and KATOIII. Inhibition of RPL15 expression by siRNA vector transfection suppressed the growth of SGC7901 cells significantly, which was independent of the expression of Cyclin D1 and B1. Down-regulation of RPL15 expression inhibited SGC7901 cell growth in soft agar and its tumorigenicity in nude mice.. RPL15 promotes cell proliferation and may be a potential target for anticancer therapy of gastric cancer.

Topics: Agar; Animals; Blotting, Western; Cell Line, Tumor; Cell Proliferation; Cyclin B; Cyclin B1; Cyclin D1; Down-Regulation; Flow Cytometry; Gene Expression Regulation, Neoplastic; Humans; Immunohistochemistry; Mice; Mice, Inbred BALB C; Mice, Nude; Neoplasm Transplantation; Oligonucleotide Array Sequence Analysis; Plasmids; Ribosomal Proteins; RNA, Small Interfering; Stomach Neoplasms; Tetrazolium Salts; Thiazoles; Transfection; Up-Regulation

The small GTPase RhoA has been implicated in the regulation of cell morphology, motility, and transformation, but the role of RhoA protein in the carcinogenesis of gastric cancer remains unclear. In the present study, we have analyzed the expression status of the RhoA protein in human gastric cancer cells and tissues and investigated the possible involvement of RhoA in regulating the malignant phenotype of gastric cancer cells.. RhoA expression was analyzed by immunohistochemistry and Western blot in gastric cancer tissues and cell lines. The RhoA-specific small interfering RNA (siRNA) vector was designed and constructed. We examined the role of RhoA in the malignant phenotype of gastric cancer cells by using siRNA knockdown and dominant-negative RhoA mutant suppression of endogenous RhoA activity.. RhoA was found frequently overexpressed in gastric cancer tissues and cells compared with normal tissues or gastric epithelial cells. RhoA-specific siRNA could specifically and stably reduce RhoA expression up to 90% in AGS cells. Both RhoA-specific siRNA and dominant-negative RhoA expressions could significantly inhibit the proliferation and tumorigenicity of AGS cells and enhance chemosensitivity of the cancer cells to Adriamycin and 5-fluorouracil.. RhoA may play a critical role in the carcinogenesis of gastric cancer, and the interference of RhoA expression and/or activity could provide a novel avenue in reversing the malignant phenotype of gastric cancer cells.

Topics: Agar; Animals; Antibiotics, Antineoplastic; Antimetabolites, Antineoplastic; Antineoplastic Agents; Blotting, Western; Cell Cycle; Cell Differentiation; Cell Line, Transformed; Cell Line, Tumor; Cell Movement; Cell Proliferation; Disease Progression; DNA; Dose-Response Relationship, Drug; Doxorubicin; Epithelial Cells; Flow Cytometry; Fluorouracil; Genes, Dominant; Humans; Immunohistochemistry; Mice; Mutation; Neoplasm Invasiveness; Neoplasm Metastasis; Oligonucleotides; Phenotype; rhoA GTP-Binding Protein; RNA, Small Interfering; Stomach Neoplasms; Tetrazolium Salts; Thiazoles; Time Factors; Transfection; Wound Healing

Although many kinds of chemosensitivity test are available for the selection of suitable anticancer agents, the results of in vitro tests against solid tumors have been generally influenced by mixed in fibroblasts, as have SDI tests. We demonstrated that the influence of fibroblasts can be excluded by performing the SDI test on an agar layer, thus significantly inhibiting the growth of fibroblasts in the liquid top layer. The sensitivity of the agar SDI test was determined on the 3-4th day after incubation because cell proliferation tended to be delayed, and there were also somewhat higher cell counts of about 40,000 per well. The inhibition indices with and without agar in vitro were the same, showing no significant differences. With nude mice, the transplanted tumor index value of the agar SDI test is higher than that of SDI, and approaches in value the SDI of a pure tumor cell, which means that the sensitivity of a solid tumor might be more accurately shown by an agar SDI test than by an SDI test.

Topics: Agar; Animals; Antineoplastic Agents; Cell Division; Cisplatin; Culture Media; Doxorubicin; Drug Screening Assays, Antitumor; Fibroblasts; Humans; Mice; Mice, Nude; Mitomycin; Stomach Neoplasms; Succinate Dehydrogenase

To evaluate the role of RARalpha gene in mediating the growth inhibitory effect of all-trans retinoic acid (ATRA) on gastric cancer cells.. The expression levels of retinoic acid receptors (RARs) in gastric cancer cells were detected by Northern blot. Transient transfection and chlorophenicol acetyl transferase (CAT) assay were used to show the transcriptional activity of beta retinoic acid response element (betaRARE) and AP-1 activity. Cell growth inhibition was determined by MTT assay and anchorage-independent growth assay, respectively. Stable transfection was performed by the method of Lipofectamine, and the cells were screened by G418.. ATRA could induce expression level of RARalpha in MGC80-3, BGC-823 and SGC-7901 cells obviously, resulting in growth inhibition of these cell lines. After sense RARalpha gene was transfected into MKN-45 cells that expressed rather low level of RARalpha and could not be induced by ATRA, the cell growth was inhibited by ATRA markedly. In contrast, when antisense RARalpha gene was transfected into BGC-823 cells, a little inhibitory effect by ATRA was seen, compared with the parallel BGC-823 cells. In transient transfection assay, ATRA effectively induced transcriptional activity of betaRARE in MGC80-3, BGC-823, SGC-7902 and MKN/RARalpha cell lines, but not in MKN-45 and BGC/aRARalpha cell lines. Similar results were observed in measuring-antiAP-1 activity by ATRA in these cancer cell lines.. ATRA inhibits the growth of gastric cancer cells by up-regulating the level of RARalpha RARalpha is the major mediator of ATRA action in gastric cancer cells; and adequate level of RARalpha is required for ATRA effect on gastric cancer cells.

Topics: Agar; Antineoplastic Agents; Cell Division; Clone Cells; Gene Expression Regulation, Neoplastic; Humans; Receptors, Retinoic Acid; Retinoic Acid Receptor alpha; Retinoic Acid Receptor gamma; Retinoid X Receptors; RNA, Messenger; Stomach Neoplasms; Transcription Factor AP-1; Transcription Factors; Transcriptional Activation; Transfection; Tretinoin; Tumor Cells, Cultured

For use in routine clinical studies, modifications to Salmon and Hamburger's human tumor stem cell assay were made. A multiplate with 24 wells made the handling of a large number of samples feasible. The addition of anticancer drugs to the bottom layer of agar facilitated avoidance of exposure to drugs before cell plating and evaluation of the effect of long-acting drugs such as 5-fluorouracil. Storage of test plates including anticancer drugs in a freezer produced no loss of colony-forming activity. Specimens from 32 patients with advanced malignancies of the GI tract were tested for sensitivity to anticancer drugs. Forty-seven percent formed enough colonies for the performance of drug testing. Two patients showed sensitivity to drugs from both in vitro and in vivo results; the ascites in one disappeared while the other showed more than 50 percent regression of hepatic metastatic foci after treatment with suitable drugs. Nine patients showed resistance to drugs from both in vitro and in vivo results. Eight showed resistance to all tested drugs.

Topics: Adult; Agar; Aged; Antineoplastic Agents; Cell Count; Cell Division; Cells, Cultured; Colonic Neoplasms; Colony-Forming Units Assay; Culture Media; Drug Evaluation, Preclinical; Female; Fluorouracil; Humans; Male; Middle Aged; Mitomycin; Mitomycins; Rectal Neoplasms; Stomach Neoplasms; Tumor Stem Cell Assay

Inhibition of leukocyte migration in agarose-agar was used as a probe for tumor-associated antigen in 3-M KCl solubilized extracts of gastric, colon, and lung cancers from humans. Twelve of 40 (30%) leukocyte preparations from gastric cancer patients, 10 of 21 (48%) from colon cancer patients, and 7 of 14 (50%) from lung cancer patients were inhibited by their respective histologically homologus cancer extract. However, among 75 preparations from various cancer patients, leukocytes from only 2 gastric cancer patients were inhibited by paired normal gastric tissue extracts. Only 2 of 68 preparations from normal individuals and none of 67 preparations from patients with nonmalignant diseases, such as gastric peptic ulcer, gastritis, colon polyposis, colitis, pulmonary tuberculosis, chronic bronchitis, and sarcoidosis, were inhibited by cancer extracts. These findings suggest the presence in KCl extracts of gastric cancer of presumed tumor-associated antigen(s) that is antigenically distinct from that of either colon or lung cancer.

Topics: Agar; Antigens, Neoplasm; Cell Migration Inhibition; Colonic Neoplasms; Female; Humans; Leukocytes; Lung Neoplasms; Male; Potassium Chloride; Stomach Neoplasms; Tissue Extracts

Topics: Agar; Electrophoresis; Gels; Humans; Peptide Hydrolases; Polyethylene Glycols; Stomach Neoplasms; Tissue Extracts

Topics: Adenocarcinoma; Adenocarcinoma, Scirrhous; Adolescent; Adult; Agar; Aged; Carcinoma; Chromatography; Colonic Neoplasms; Gallbladder Neoplasms; Hemangiosarcoma; Humans; Liver Neoplasms; Lymphoma, Non-Hodgkin; Middle Aged; Neoplasm Proteins; Neoplasm Recurrence, Local; Pancreatic Neoplasms; Protein Denaturation; Retroperitoneal Neoplasms; Stomach Neoplasms

Topics: Agar; Aged; Blood Protein Electrophoresis; Breast Neoplasms; Carcinoma, Bronchogenic; Colonic Neoplasms; Esophageal Neoplasms; Female; gamma-Globulins; Humans; Kidney Neoplasms; Lung Neoplasms; Middle Aged; Neoplasm Metastasis; Neoplasms; Stomach Neoplasms

Topics: Agar; Blood Proteins; Electrophoresis; Gels; Humans; Neoplasm Proteins; Stomach Neoplasms

Topics: Agar; Animals; Arthritis, Rheumatoid; Beta-Globulins; Complement System Proteins; Hemolysis; Humans; Hydrazines; Immune Sera; Immunoelectrophoresis; Liver Cirrhosis; Multiple Myeloma; Precipitins; Stomach Neoplasms

Topics: Agar; Antigens; Embryo, Mammalian; Female; HeLa Cells; Humans; Mycoplasma; Neoplasms, Experimental; Precipitin Tests; Skin; Stomach Neoplasms

Topics: Agar; Antigens; Electrophoresis; Esterases; Gastric Mucosa; Humans; Immunoelectrophoresis; Neoplasm Proteins; Peptide Hydrolases; Stomach Neoplasms; Tissue Extracts

Topics: Agar; Antigens; Humans; Precipitins; Stomach Neoplasms