Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0677930 (primary tumor)
 20,210 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Deletion of the short arm of chromosome 1 is among the most recurrent cytogenetic alterations found in neuroblastoma and has been associated with short survival. However, this prognostic information, which relies on time-consuming techniques, is not yet routinely exploited. In order to set up a reliable and simple routine test to determine 1p deletion in neuroblastoma, we have used the polymerase chain reaction to genotype neuroblastoma DNA at 2 loci containing a variable number of tandem repeats and located on the distal part of the short arm of chromosome 1. Agarose gel electrophoresis and ethidium bromide staining of the amplification products enable a simple determination of constitutional and tumor genotypes at these loci to be made. A total of 37 samples from 29 patients were studied with this technique. Loss of heterozygosity (LOH) could be identified in 8 cases. In each case the results obtained were in agreement with those achieved by the Southern procedure. This technique will be of particular interest in the pretherapeutic analysis of 1p deletions in small tumor samples obtained by fine-needle aspirates of the primary tumor. It should also enable retrospective studies from paraffin-embedded tumor fragments to be made and provide information for the analysis of tumor heterogeneity in neuroblastoma and in other tumors with 1p deletions.
 ...
PMID:PCR assay for chromosome 1p deletion in small neuroblastoma samples. 139 34

Drug sensitivity assays were performed using a variation of a colorimetric [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT)] assay on V79, CHO-AuxB1, CHRC5, NCI-H460, and NCI-H249 cell lines following optimization of experimental conditions for each cell line. Results from this assay were compared with data assimilated simultaneously by clonogenic assay and by dye exclusion assay. Good correlation was observed using the CHO-AuxB1 cell line and the pleiotropic drug-resistant mutant CHRC5, with similar degrees of relative resistance observed with both the MTT and clonogenic assays. Good correlation was observed between the clonogenic and MTT assays for 1-h drug exposures, although the MTT assay was more sensitive to vinblastine. In general, the clonogenic assay was more sensitive when continuous drug exposures were utilized, although this was primarily related to the increased drug exposure time. While the use of the MTT assay in drug sensitivity testing of primary tumor samples is limited, since contaminating normal cells may also reduce the tetrazolium, the MTT assay can be semiautomated, and therefore it offers a valid, simple method of assessing chemosensitivity in established cell lines.
 ...
PMID:Evaluation of a tetrazolium-based semiautomated colorimetric assay: assessment of chemosensitivity testing. 380

The prognosis of patients with follicular (FTC) and papillary (PTC) thyroid cancer depends on age and the size and extent of the tumor. Differentiated thyroid cancers bind more epidermal growth factor (EGF) than normal thyroid tissue, but the role of EGF in the proliferation and invasion of thyroid cancer is unknown. We investigated the effects of EGF on growth, migration, and invasion in a follicular thyroid cancer that metastasized to cervical lymph nodes and the lung (FTC 133, primary; FTC 236, lymph node; and FTC 238, lung metastasis) and in a papillary thyroid cancer (PTC-UC3). As measured by the formazan method (dimethylthiazol-diphenyltetrazolium bromide), EGF caused a dose- and time-dependent increase in the growth of FTC 133 and PTC-UC3 by 25%, but its stimulatory effect on growth of the metastatic FTC subclones was smaller (FTC 236, 14%; FTC 238, 8%; P < 0.001). EGF also enhanced the ability of all cell lines to migrate (through 8-microns pore membranes without Matrigel) or invade (membranes with Matrigel). Migration of FTC 133 was enhanced from 86% migrated tumor cells to 95% after 72 h (P < 0.02). Again, stimulation by EGF was lower in FTC 236 and FTC 238. EGF increased migration in PTC-UC3 from 49% to 58%. EGF stimulated invasion of FTC 133 from 17.5% to 24.9%. In the absence of EGF, FTC 238 was the most invasive tumor, but, again, the EGF stimulatory effect was less pronounced than in the primary tumor. EGF stimulated the invasion of PTC-UC3 from 10.9% to 14.3% (P < 0.03). EGF also stimulated the growth of thyroid cancer xenografts in nude mice. Although all FTC cell lines were 100% tumorigenic in nude mice, PTC-UC3 was less tumorigenic. However, after sc inoculation of EGF-pretreated tumor cells, 7 of 10 animals developed tumors (mean size, 2.3 cm3) compared to 2 of 10 animals (mean size, 1.4 cm3) in the control group (P < 0.02). In summary, EGF stimulates the growth and invasion of differentiated thyroid cancer cells in culture and in nude mice. Escape from growth factor control, such as in FTC 236 and FTC 238, may be an important step in the development of metastatic thyroid cancer.
 ...
PMID:Epidermal growth factor enhances proliferation, migration, and invasion of follicular and papillary thyroid cancer in vitro and in vivo. 804 55

The invasion-3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay, which evaluates invasive potential into the reconstituted basement membrane, Matrigel, was performed on 49 human gastrointestinal carcinomas transplanted in nude mice. There were 19 colorectal carcinomas, 10 pancreatic carcinomas, 10 gastric carcinomas, 8 esophageal carcinomas, and 2 bile duct carcinomas. The percent invasion (PI) value of each tumor by the invasion-MTT assay expresses the invasive rate of tumor cells into the Matrigel as a percentage. There were no significant differences in correlations between the PI values and primary tumor site, clinicopathological findings, tumor doubling time, or DNA index; however, the PI values of primary tumors and lymph nodes with liver metastases were significantly higher than those of primary tumors without liver metastasis (P < 0.05). Furthermore, the primary tumors with synchronous (P < 0.05) or asynchronous (P < 0.01) liver metastases showed significantly higher PI values compared with the primary tumors without liver metastases. These results suggest that PI is not only an independent factor to predict liver metastasis, but it also correlates closely with liver metastasis. Thus, the invasion-MTT assay for primary tumors might be clinically useful to predict liver metastasis in patients following surgery for gastrointestinal carcinomas.
 ...
PMID:The invasion-MTT assay as a predictor of liver metastasis using human gastrointestinal carcinomas transplanted in nude mice. 930 67

The liver metastasis of gastric carcinoma is resistant to conventionally available treatment. Twenty patients with liver metastasis of gastric cancer were treated by arterial drug infusion using a reservoir and seven cases were treated with systemic chemotherapy. The resected primary gastric cancer specimen was used for chemosensitivity assay with 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl-2H tetrazolium bromide (MTT) endpoint, and the patients were treated without reference to the results of the chemosensitivity assay. The mean survival period was assessed according to the histology of the primary lesion, the grade of liver metastasis and, the presence of peritoneal dissemination. No significant differences were observed in the primary tumor histology and grade of liver metastasis, but the survival period of the patients with liver metastasis and peritoneal dissemination was significantly shorter than that of the patients without peritoneal dissemination. Nine patients were treated with drugs that were effective in the chemosensitivity assay, and their responses included two complete responses and two partial responses; these patients showed a significantly prolonged survival period compared with patients treated with drugs that were not effective in the assay. The chemosensitivity assay is useful for evaluating the effectiveness of antitumor agents against liver metastasis of gastric cancer.
 ...
PMID:Chemosensitivity testing of primary tumor cells from gastric cancer patients with liver metastasis can identify effective antitumor drugs. 1069 26

Metastatic renal-cell carcinoma (RCC) is not responsive to conventional cytotoxic chemotherapy, but a subset of patients achieve a durable remission with the use of interleukin-2 (IL-2). IL-2 is currently the only Food and Drug Administration (FDA)-approved treatment for metastatic RCC, and it benefits 10-20% of those who receive it. However, it is accompanied by significant, occasionally life-threatening toxicity. Attempts to maintain the efficacy of IL-2 while minimizing systemic side effects have led to the development of IL-2 gene therapies. Leuvectin is a plasmid DNA/lipid complex composed of a plasmid DNA expression vector (VCL-1102, 30) encoding human IL-2 complexed in a 5:1 mass ratio with DMRIE/DOPE lipid (1,2-dimyristyloxypropyl-3-dimethylhydroxyethyl ammonium bromide/dioleoylphosphatidyl ethanolamine), which has been developed for the treatment of malignancy. DMRIE/DOPE is a cationic lipid that has been shown to facilitate in vitro transfection of plasmid DNA. It has been demonstrated that in vitro transfection with the IL-2 plasmid DNA/DMRIE/DOPE complex results in the expression of sustained levels of biologically active IL-2. Established human tumor cell lines and primary human tumor cells obtained from biopsies are readily transfected in vitro, resulting in the expression of IL-2. Following in vitro transfection, IL-2 expression has been found to persist for up to several weeks in primary tumor cells. In preclinical efficacy studies in a murine model of renal-cell carcinoma the direct intratumoral administration of an IL-2 plasmid DNA/DMRIE/DOPE complex resulted in complete tumor regression in the majority of mice. In preclinical animal-safety studies, repeated administration of Leuvectin was safe and well tolerated. Following these promising preclinical trials, Leuvectin has been taken into clinical trial. The results of two early studies indicate that Leuvectin is safe, is free of systemic toxicity, and has biologic activity.
 ...
PMID:Intratumoral interleukin 2 for renal-cell carcinoma by direct gene transfer of a plasmid DNA/DMRIE/DOPE lipid complex. 1085 52

Considerable research effort is currently being directed towards understanding the mechanisms mediating the antiproliferative effects of non-steroidal anti-inflammatory drugs (NSAIDs) and, more recently, of cyclooxygenase (COX)-2 inhibitors as well. A key question is whether NSAIDs (excluding sulindac) exert their anticarcinogenic effects in vivo by a mechanism that is dependent on their capacity to inhibit COX activity. Some studies with cultured tumor cells in vitro have argued against such a linkage, showing that NSAIDs inhibit cell replication and/or augment apoptosis only at concentrations that exceed those required to inhibit COX activities 10- to 100-fold. The significance of these results for the observed anticarcinogenic effects of NSAIDs in vivo has not yet been evaluated. We addressed this question by comparing, for the same tumor cells, the effects of the NSAID indomethacin on cell growth parameters when the cells were grown in culture to the effects seen in the in vivo growing tumor in the mouse. Indomethacin added to cultured Lewis lung carcinoma cells exerted a potent antiproliferative effect ((3)H thymidine assay) and reduced cell viability (MTT[3-(4,5-dimethyl(thiazol-2-yl)-2,5 diphenyl tetrazolium bromide] assay) at low doses (10-20 microM) in parallel with its inhibitory effect on cellular cyclooxygenase. These effects of indomethacin appeared to arise from a clear antiproliferative shift in the profile of the cell cycle parameters towards a reduced percentage of cells at the S and G(2)/M phases, together with an increased percentage of cells at the G(1) phase. Significantly, similar results were seen when indomethacin was given in vivo at the low dose of 2 mg per kg/day, which blocked blood platelet COX activity and at the same time produced a delay in tumor growth initiation and attenuation of apparent primary tumor growth as well as growth of lung metastases. These results thus provide strong support for the notion that COX inhibition is a major determinant in the antitumorigenic effect of indomethacin in vivo.
 ...
PMID:Comparative effects of indomethacin on cell proliferation and cell cycle progression in tumor cells grown in vitro and in vivo. 1123 99

Lymph node metastasis is often the first indication of the aggressiveness of breast cancer. Effective chemotherapy in breast cancer depends on targeting the metastatic component of the disease. In order to optimize chemotherapy in the metastatic target of breast cancer, the histoculture drug response assay (HDRA) was performed on surgical specimens of primary tumor and axillary lymph node metastasis from 30 breast cancer patients. The surgical specimens were cut into approximately 10 mg pieces, and placed onto the collagen gel sponges in the medium containing previously-determined cutoff concentrations of doxorubicin (DXR), 5-fluorouracil (5-FU), cisplatin (DDP), and mitomycin C (MMC). After incubation for 7 days, the chemosensitivity of the tumor fragments was evaluated with the 3-(4,5-dimethythiazol2yl)-2,5-diphenyl-2H tetrazolium bromide (MTT) endpoint. The lymph node metastases were more resistant than the primary tumor for DXR, 5-FU, and MMC (p < 0.05) but not for CDDP. The data suggest that both primary tumor and metastases from individual patients should be tested in the HDRA to enhance clinical efficacy of chemotherapy.
 ...
PMID:Chemosensitivity of breast cancer lymph node metastasis compared to the primary tumor from individual patients tested in the histoculture drug response assay. 1126 34

The aim of the study was to investigate the antitumor and/or preventive effect of BC-4, an isomeric compound isolated from the plant Boswellia carteri Birdw. containing alpha- and beta-boswellic acid acetate in 1:1, MW 498.3. We used the MTT (3-(4,5-dimethylthiazol-2-yl) 2,5-diphenyltetrazolium bromide) assay to study the growth inhibition activity of BC-4. Tumor cells migration within a three-dimensional collagen matrix was recorded by time-lapse videomicroscopy and computer-assisted cell tracking. Topoisomerase II was isolated from mouse melanoma B16F10 cells and its activity was determined by its ability to cut plasmid pBR322 DNA. The secretion and activity of matrix metalloproteinases (MMPs) from human fibrosarcoma HT-1080 cells were determined by gelatin zymography. BC-4 was a cytostatic compound and could induce the differentiation of B16F10 mouse melanoma cells, blocked the cell population in G1 phase and inhibited topoisomerase II activity. The G1 phase population of B16F10 cells was increased from 57.4 to 87.7%, while S phase population was reduced from 33.3 to 5.9% after treatment with BC-4 at 25 microM concentration for 48 h. BC-4 also inhibited the migration activity of B16F10. BC-4 could induce apoptosis of HT-1080 cells, as proved by acridine orange fluorescence staining, Wright-Giemsa staining, electromicroscopy, DNA fragmentation and flow cytometry. BC-4 inhibited the secretion of MMPs from HT-1080 cells, too. In conclusion, if it turns out that BC-4 is a well tolerated substance, exhibiting no significant toxicity or side effects, being evaluated currently in China, BC-4 is a good candidate for the prevention of primary tumor, invasion and metastasis.
 ...
PMID:Boswellic acid acetate induces differentiation and apoptosis in highly metastatic melanoma and fibrosarcoma cells. 1260 Apr 19

The aim of this study was to determine the basis for anti-tumor immune reactivity observed in patients with human epidermal growth factor receptor-2 (HER-2) (3+) breast carcinoma using an in vitro model in which the role of the HER-2-specific monoclonal antibody Herceptin was also investigated. Patients with metastatic breast cancer who had their primary tumor resected were included in this study. Peripheral blood mononuclear cell (PBMC)-dependent cytotoxicity in the presence or absence of Herceptin were assessed using the survival of target breast adenocarcinoma MDA-MB-361 cells as a parameter in a (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) test. We observed a significant increase in PBMC-dependent cytotoxicity when autologous serum was introduced in the assay. Furthermore, the addition of Herceptin significantly increases their cytotoxicity. These data suggest that autologous serum constitutively contains factors that might affect PBMC-dependent cytotoxic activity against HER-2 positive cancer cells.
 ...
PMID:The antitumor immune response in HER-2 positive, metastatic breast cancer patients. 1578 49


1 2 Next >>