Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Retinoblastoma is a rare malignant tumour of the developing retina with an incidence of 1 in 20,000 live births in all human races. Chemotherapy is used in retinoblastoma as adjuvant therapy to prevent the growth of metastases and to treat metastatic disease once this has become clinically apparent. Current regimens are based on empirical drug combinations, and few clinical trials have been conducted because of the rarity of this tumour. Chemosensitivity testing offers a way of testing a large number of agents against tumours. The ATP-based chemosensitivity assay (ATP-TCA) has already helped to design new regimens for melanoma and breast and ovarian cancer. Primary retinoblastoma tumour material was obtained from 10 eyes, 7 of which contained sufficient viable cells for ATP-TCA. The results show very high sensitivity to single agents, particularly cisplatin, doxorubicin and vinca aLkaloids. Of the anti-metabolites tested, 5-FU is relatively disappointing (although still active), and gemcitabine shows considerable activity consistent with a cytotoxic effect. The shape of the inhibition curves is interesting. There is a plateau effect with the topoisomerase inhibitors and vinblastine, which is not present with the cisplatin. One tumour was much more resistant than the others tested, particularly to vinblastine but also to the topoisomerase inhibitors, which failed to achieve complete kill at any concentration tested, consistent with a multidrug resistance phenotype. Of the combinations (VAC and VEC), the VAC regimen looks marginally more active in the more resistant of the two cases tested to date. These data confirm that retinoblastoma is a rapidly growing malignancy that is very susceptible to cytotoxic drugs of all types. Chemosensitivity testing provides a practical method of testing new regimens before clinical trials in retinoblastoma patients.
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PMID:The chemosensitivity profile of retinoblastoma. 1252

The prognosis of patients with metastatic melanoma remains poor. In patients with distant metastases only low response rates between 10% and 15% have been achieved by the most effective cytostatics in single-agent therapy leading to a mean 5-year survival rate of less than 5%. More aggressive treatment regimens using multidrug chemotherapy yielded response rates of up to 40% but failed to show a significant benefit in overall survival compared to single-agent therapy. However, complete remissions of metastatic lesions after multidrug cytostatic regimens have been reported in some cases of melanoma patients. To evaluate an in vitro test system providing information on the drug sensitivity profile of melanoma cells, we examined tumor tissue specimens from 31 metastatic melanoma patients with an ATP-based chemosensitivity assay (ATP-TCA) testing eight anticancer drugs alone or in different combinations. Chemosensitivity was assessed using a luciferin-luciferase- based luminescence assay providing individual chemosensitivity indices for each test drug. We found a heterogeneous chemosensitivity in the melanoma tissue samples tested. The highest sensitivity was detected for the combination of treosulfan and gemcitabine, with 76% of the tissue samples revealing high sensitivity and 10% resistance, followed by the combination of paclitaxel and doxorubicine (66%/0%), gemcitabine and cisplatin (55%/21%),and paclitaxel and cisplatin (46%/8%). Our data indicate that the ATP-TCA can be used to select patients who might benefit from an individually adapted cytostatic therapy. On the basis of these results a multicenter trial has recently been initiated to evaluate the feasibility and predictive value of an ATP-TCA directed chemotherapy in metastatic melanoma patients.
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PMID:Chemosensitivity testing in malignant melanoma. 1252 1

The therapy of metastatic malignant melanoma is limited by poor responses and short overall survival. Thus it remains important to identify and test potential new drugs in this disease. To examine the effects of the bifunctional alkylating cytostatic treosulfan, an in vitro microplate ATP bioluminescence assay (ATP-TCA) was used. Five highly chemoresistant melanoma cell lines and melanoma cells freshly isolated from metastases surgically resected from stage IV melanoma patients (n = 10) were incubated with treosulfan. Three cell lines and eight of ten tested tumor cells isolated from melanoma metastases showed tumor growth inhibition after incubation with treosulfan. Therefore, 14 patients with rapidly progressing stage IV malignant melanoma who were pretreated with at least one standard chemotherapy regimen received treosulfan. In this population of patients with highly refractory advanced melanoma one complete remission (7.1%), two partial remissions (14.3%), and three cases of stable disease (21.4%) were observed. Median time to progression and median overall survival for all patients measured from the beginning of treosulfan treatment were 5 months [95% confidence interval (CI) 1.98-2.57 months] and 9 months (95% CI 3.92-8.69 months), respectively. On the basis of these data a multicenter phase II trial was initiated. A total of 31 patients with stage IV melanoma were included and treated second-line with 8 g/m2 i.v. treosulfan. From this group 26 patients were evaluable. No objective remission (CR, PR) was observed, 5 of 26 patients (19%) had stable disease, and 21 patients had progressive disease. Median overall survival was 6.5 months (95% CI 3.1-10 months). Toxicity of treosulfan was moderate. Patients with treosulfan-sensitive melanoma metastases showed better response rates and prolonged survival compared with patients who were not tested before treosulfan treatment. We therefore suggest further studies with first-line treosulfane alone or in combination with gemcitabine or cytosine arabinoside together with pretherapeutic chemosensitivity testing that may help to select patients who might benefit from specific chemotherapy.
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PMID:Treosulfan in the treatment of metastatic melanoma: from chemosensitivity testing to clinical trials. 1252 7

Gap junctions, or connexons, are formed by connexin proteins and connect most cells in the body to form water-filled channels directly linking the cytoplasm. Among the molecules known to be transferred via junctions are cAMP, ATP, IP3 and glucose. Tumor cells are in general deficient in functional gap junctions either as a result of gene silencing, or failure to correctly process and assemble connexons. Tumor promoters inhibit function whereas certain cancer preventive agents increase junctional communication. When connexin expression in tumor cells is forced by introduction of exogenous genes or is increased by pharmacological agents, connexin expression reduces growth in suspension and growth as xenografts in nude mice. It is as yet unclear if in tumor cells these actions depend on junctional transfer of signal molecules or reflect some other function of these genes. Restoration of connexin function offers an exciting opportunity to delay tumor progression and inhibit metastasis.
Cancer Metastasis Rev 2002
PMID:Cancer chemoprevention by connexins. 1254 61

Photodynamic therapy (PDT) of cancer (1, 2) is a well-established treatment modality that uses light excitation of a photosensitive substance to produce oxygen-related cytotoxic intermediates, such as singlet oxygen or free radicals (3, 4). Although PDT is advantageous over other forms of cancer treatments because of its limited side effects, its main disadvantage is the poor accessibility of light to more deeply lying malignancies. External light sources such as lasers or lamps can be applied either noninvasively to reach tumors that lie well within the penetration depth of the light or in a minimally invasive fashion (interstitial treatments) in which optical fibers are placed intratumorally through needles. Even with the second approach, light distribution over the tumor is not homogeneous and nonidentified metastatic disease is left untreated. CL, the chemical production of light, is exemplified by firefly light emission mediated by the enzymatic (luciferase + ATP) oxidation of D-luciferin to oxyluciferin (5). This mobile light source is a targetable alternative to external sources of illumination. Here we show the in vitro photodynamic effect of rose bengal activated by intracellular generation of light, in luciferase-transfected NIH 3T3 murine fibroblasts.
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PMID:Firefly luciferin-activated rose bengal: in vitro photodynamic therapy by intracellular chemiluminescence in transgenic NIH 3T3 cells. 1270 68

Metalloproteinases (MMP), particularly MMP-9 produced by the intratumor monocyte/macrophages, play an important role in tumor invasion and metastases. Recent clinical trials in patients with primary breast cancer suggest that bisphosphonates (BP), above all clodronate, may reduce bone metastases. The aim of the present study was to evaluate whether the effects of BPs on cancer dissemination include inhibition of MMP-9 production in human monocyte/macrophages. The effects of clodronate and pamidronate on the MMP-9 expression in and secretion from stimulated human monocyte/macrophages were measured using quantitative reverse transcriptase - polymerase chain reaction (RT-PCR) and enzyme-linked immunoadsorbent assay (ELISA), respectively. The MMP-9 mRNA levels remained relatively stable in the presence of clodronate. In contrast, pamidronate at 30 microM-300 microM increased the mRNA levels 5- to 10-fold. MMP-9 secretion was dose-dependently down-regulated by clodronate whereas pamidronate at 30 microM induced a 50% increase on MMP-9 secretion (p < 0.05), followed by a down-regulation at higher concentrations. The results suggest that MMP-9 is differentially regulated at mRNA and enzyme protein level by BPs, which affect ATP-dependent intracellular enzymes (clodronate) or post-translational modification of GTPases (pamidronate). These findings may have implications for the therapeutic use of these compounds.
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PMID:Regulation of MMP-9 (gelatinase B) in activated human monocyte/macrophages by two different types of bisphosphonates. 1295 50

Advanced or metastatic disease is common in both oesophagogastric and colorectal cancers, with poor 5-year survival despite palliative chemotherapy. We have investigated the sensitivity of gastrointestinal tumours to gemcitabine in combination with mitomycin C (GeM), using a modified ex vivo ATP-based tumour chemosensitivity assay (ATP-TCA). Tumour material from 41 colorectal and 22 oesophagogastric cancers were assessed. The GeM combination showed variable but definite activity in most of the samples tested. The results show that GeM achieves >95% inhibition at concentrations within the range achievable clinically in 60% of colorectal tumours (21 out of 35) and 38% of oesophagogastric tumours (five out of 13) tested. We did not identify any significant difference in sensitivity using concurrent or sequential exposure of tumour-derived cells to these two drugs. The results from this study suggest that GeM may be a useful combination in the treatment of advanced gastrointestinal malignancy.
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PMID:Combination chemotherapy in advanced gastrointestinal cancers: ex vivo sensitivity to gemcitabine and mitomycin C. 1467 10

The vast majority of mesenchymal tumors originating from the GI tract consists of gastrointestinal stromal tumors (GIST), an entity just recently defined. The incidence is estimated to be around 10 - 20/1000000, the median age at diagnosis has been reported to be 55 to 65 years. GISTs most commonly occur in the stomach or duodenum, followed by the small intestine. About half of the patients present with metastatic disease at first diagnosis, predominantly in the liver or periteneum. GISTs are strongly and uniformly positive for CD117 (c-kit), a type III receptor-tyrosine kinase. Kit mutations, mostly in exon 11, leading to ligand independent constitutive activation are supposed to play a major role in the pathogenesis of GIST. Until recently no active systemic treatment was available for advanced gastrointestinal stromal tumors. Imatinib (STI571 = Glivec) is a rationally designed, orally available phenylaminopyrimidin analogue. The mechanism of action consists of a competitive interaction with the ATP-binding pocket of specific tyrosine kinases. Early results from clinical trials with response rates around 60 % and progression arrest in more than 80 % of patients resulting in fast relief of symptoms, confirm the high activity of this novel treatment. The role of adjuvant treatment after potentially curative resection of GIST is currently evaluated in ongoing clinical trials. Patients with progressive disease while under treatment with Imatinib should be enrolled in studies testing novel treatment strategies as RAD001, PKC412 or SU11 248.
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PMID:[Gastrointestinal stromal tumors (GIST)]. 1509 24

Breast cancer has a significant capacity to metastasize to bone. Bisphosphonates are the standard treatment for hypocalcaemia of malignancy (HCM), which is a common complication of bone metastasis. The combination of bisphosphonates with standard anticancer drugs such as paclitaxel or tamoxifen results in a synergistic apoptotic effect greater than that produced by either single agent alone. Potential antitumour effects in vitro of the two bisphosphonates zoledronic acid (Zol) and ibandronate (Ib) (each at 30 microM) combined with different anticancer drug combinations: cyclophosphamide/metotrexate/5-fluorouracil (CMF), epirubicin/cyclophosphamide (EC), epirubicin/paclitaxel (ET), and epirubicin/docetaxel (EDoc) were investigated using ATP-cell viability assay (ATP-CVA). Twenty cases of female primary, invasive breast cancer were assessed. Ibandronate and zoledronic acid alone showed an inhibitory effect on breast cancer tumour cells in vitro. The breast tumour growth inhibition effect for those two drugs amounted to 22 and 25% respectively. Inhibitory effects were clearly visible for all four combinations of anticancer drugs together with both bisphosphonates. Combinations of anticancer drugs with zoledronic acid seem to be more effective with respect to tumour growth inhibition than combinations with ibandronate.
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PMID:Breast tumour growth inhibition in vitro through the combination of cyclophosphamide/metotrexate/5-fluorouracil, epirubicin/cyclophosphamide, epirubicin/paclitaxel, and epirubicin/docetaxel with the bisphosphonates ibandronate and zoledronic acid. 1549 1

The SWI/SNF enzymes belong to a family of ATP-dependent chromatin remodeling enzymes that have been functionally implicated in gene regulation, development, differentiation and oncogenesis. BRG1, the catalytic core subunit of some of the SWI/SNF enzymes, can interact with known tumor suppressor proteins and can act as a tumor suppressor itself. We report that cells that inducibly express ATPase-deficient versions of BRG1 increase in cell volume, area of attachment and nuclear size upon expression of the mutant BRG1 protein. Examination of focal adhesions reveals qualitative changes in paxillin distribution but no difference in the actin cytoskeletal structure. Increases in cell size and shape correlate with over-expression of two integrins and the urokinase-type plasminogen activator receptor (uPAR), which is also involved in cell adhesion and is often over-expressed in metastatic cancer cells. These findings demonstrate that gene expression pathways affected by chromatin remodeling enzymes can regulate the physical dimensions of mammalian cell morphology.
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PMID:Inducible changes in cell size and attachment area due to expression of a mutant SWI/SNF chromatin remodeling enzyme. 1553 31


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