Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The possible mitogenic activity of fibronectin (FN) in human primary and metastatic melanoma lines and clones and the involvement of integrins in mediating this effect were evaluated. Quescent human melanoma cells cultured in serum-free medium proliferated in a dose- and time-dependent fashion to immobilized FN as indicated by [3H]thymidine incorporation, increment of cell number, and cell cycle analysis. This response to FN was observed with tumor clones isolated from a subcutaneous metastasis and with primary or metastatic melanomas from different patients, but only when tumor cells expressed the alpha 5 subunit of the FN receptor (i.e., VLA-5). Proliferation to FN by a primary tumor (Me4405) expressing all FN receptors and by a tumor clone (2/60) lacking only the alpha 4 subunit was inhibited by monoclonal antibodies to the alpha 5 and beta 1 but not by monoclonal antibodies to other subunits of FN receptors. Mapping of FN regions responsible for the proliferative signal was performed by stimulating melanoma cells with different FN proteolytic fragments and indicated that a significant mitogenic signal was provided by the M(r) 120,000 alpha-chymotrypsin fragment containing the Arg-Gly-Asp sequence. The proliferation of melanoma cells to FN and to FN fragments was also significantly inhibited by peptides containing the Arg-Gly-Asp sequence. These data indicate that FN can stimulate the proliferation of quiescent melanoma cells and that integrins as alpha 5 beta 1 are involved in the response of tumor cells to this extracellular matrix protein.
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PMID:Role of the alpha 5 beta 1 integrin receptor in the proliferative response of quiescent human melanoma cells to fibronectin. 138 57

The growth of Demel human metastatic melanoma cells was inhibited by 12-O-tetradecanoylphorbol-13-acetate (TPA) and other nonphorbol tumor promoters including palytoxin and okadaic acid. Using flow cytometry, we have demonstrated that the cells arrested growth in G1 and G2 phases of the cell cycle. Detailed analysis of the kinetics of the growth arrest in unsynchronized cells showed that (a) the growth arrest was transient and peaked 16-20 h following addition of TPA; (b) effects of TPA on cell growth began within 1-2 h after the addition; and (c) cells completed S phase and arrested in G2. In addition, TPA induced a pronounced morphological change, which peaked by 1 h and gradually subsided over 24 h. In populations of cells synchronized in G1 using lovastatin, (a) addition of TPA blocked the onset of DNA synthesis up to the end of G1; (b) the lag between addition of the drug and onset of DNA synthesis was less than 30 min; and (c) addition of TPA at the end of G1 prevented the increased phosphorylation of p34cdc2, as determined by immunoprecipitation. The experiments reported here show that TPA transiently blocked the proliferation of Demel melanoma cells at the G1-S border and in G2, thus preventing cells from progressing through the cell cycle. These experiments suggest that pathways involving protein kinase C interact with and rapidly alter the molecular pathways involving p34cdc2 which regulate the onset of DNA synthesis and the G2-M transition.
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PMID:12-O-tetradecanoylphorbol-13-acetate induces transient cell cycle arrest in G1 and G2 in metastatic melanoma cells: inhibition of phosphorylation of p34cdc2. 139 Mar 35

A new polyvalent melanoma cell vaccine (MCV) was administered to 136 stage IIIA and IV (American Joint Committee on Cancer) melanoma patients. Induction of cell-mediated and humoral immune responses to common melanoma-associated antigens present on autologous melanoma cells was observed in patients receiving the new MCV. This was accompanied by increased activation of tumor-infiltrating lymphocytes. Survival correlated significantly with delayed cutaneous hypersensitivity (p = 0.0066) and antibody responses to MCV (p = 0.0117). Of 40 patients with evaluable disease, nine (23%) had regressions (three complete). From our historical database of 126 stage IIIA and 1275 stage IV melanoma patients, there were no significant changes in the natural history of metastatic melanoma during the past 20 years. Univariate and multivariate analyses demonstrated prognostic significance for site of metastases (p = 0.0001) and immunotherapy with the new MCV (p = 0.0001). Overall our new MCV increased the median and 5-year survival of stage IIIA melanoma patients with regional soft tissue metastases twofold (p = 0.00024), and stage IV patients threefold (p = 0.0001) compared with previous immunotherapy and other treatments.
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PMID:Prolongation of survival in metastatic melanoma after active specific immunotherapy with a new polyvalent melanoma vaccine. 141 96

The efficacy of present day antineoplastic regimens depends upon the delivery and penetration of therapeutic agents through the tumor vascular and interstitial spaces to the tumor cell target. The distribution of relevant molecules or cells in a solid tumor is often poor and heterogeneous and is believed to be due to a number of pathophysiological factors, including elevated interstitial fluid pressure (IFP). Using the wick-in-needle technique, IFP was measured in primary breast and colorectal carcinomas as well as their respective metastases to the lymph nodes and liver in a total of 17 patients. IFP was also measured in one recurrent renal cell carcinoma, one melanoma metastasis to the lymph nodes, and another melanoma metastasis to the lung. IFP varied from 4 to 50 mm Hg with a mean +/- SD of 20 +/- 13 mm Hg in the neoplasms (n = 41 measurements; n = 21 tumors), while IFP in normal tissues had a mean of 2 +/- 4 mm Hg (n = 11). The mean IFPs for metastatic melanoma, primary breast carcinoma, and liver metastases from a colorectal primary were found to be 33 +/- 14, 15 +/- 9, and 21 +/- 12 mm Hg, respectively. In the renal cell carcinoma, the pressure was 38 mm Hg. These results agree with the findings of our 3 previous studies examining IFP in human superficial melanomas (14.3 +/- 12.5 mm Hg, n = 12), cervical carcinomas (15.7 +/- 5.7 mm Hg, n = 12), and head and neck tumors (13.2 +/- 8.8 mm Hg, n = 19), and indicate that in all types of human tumors studied to date, IFP was significantly elevated above that of normal tissue. This observation may be useful in localizing tumors during needle biopsy.
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PMID:Interstitial hypertension in human breast and colorectal tumors. 142 83

Peripheral blood lymphocytes from 146 patients with metastatic melanoma undergoing interleukin 2 (IL-2)-based immunotherapy were characterized for HLA A, B, Cw, DR, DQw, and DRw specificities. Patients had been enrolled into sequential treatment protocols with either IL-2 alone (28) or in combination with tumor-infiltrating lymphocytes (TILs) (86), alpha-interferon (26), lymphokine-activated killer cells (16), radiation therapy (7), cyclophosphamide (3), tumor necrosis factor (1), and interleukin 4 (1) for a total of 168 courses of therapy. HLA phenotype was then correlated with response rate and toxicity to IL-2. We noted: (a) a significant difference in the frequency of A11 (20.5% versus 10.2%; P < 0.05) allele between melanoma patients and the North American Caucasian population; (b) a significantly higher frequency of A11 phenotype among responders (40.5%) than in the melanoma patient population (20.5%; P < 0.01), which was even more obvious among patients responding to TIL therapy (47.4% versus 22.1%; P < 0.05); within TIL patients, responders also had an increased frequency of A19 (42.1% versus 25.6%; P < 0.05); (c) a correlation between the number of TILs received and response rate (P < 0.005); and (d) an association between DR4 haplotype and decreased tolerance to IL-2 among the patients receiving TILs (P = 0.01). These results suggest that, in melanoma patients, some HLA Class I specificities may predict for a greater likelihood of response to IL-2-based therapy, while HLA Class II phenotype correlates with tolerance to the combination of TIL and IL-2 therapy.
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PMID:HLA association with response and toxicity in melanoma patients treated with interleukin 2-based immunotherapy. 142 1

Nine morphologic patterns of tumor vessels were identified in eyes removed for ciliary body or choroidal melanoma by the examination of tissue sections stained with fluorescein-conjugated Ulex europaeus I using laser scanning confocal microscopy. This technique also highlights intravascular tumor invasion. Each of these nine morphologic patterns of tumor vessels also may be demonstrated by a modification of the periodic acid-Schiff reaction, viewed with a green narrow band pass filter, but this modified histochemical technique does not accurately identify intravascular tumor invasion. Most tumors have a heterogeneous distribution of vascular patterns. Melanomas in two groups of 20 tumors each were matched by tumor size and location (one group of tumors from patients who survived at least 15 years free of metastatic melanoma after enucleation and one group of tumors from patients who died of metastatic melanoma). A matched case-control analysis indicates that the presence of at least one closed vascular loop in a uveal melanoma is the most significant vascular pattern associated with death from metastatic melanoma after enucleation. Closed loops are associated with other histologic features that are predictive of an unfavorable outcome after enucleation: epithelioid cells and mitotic figures. In this preliminary study the formation of closed vascular loops is a marker of tumor progression in ciliary body and choroidal melanomas.
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PMID:The morphologic characteristics of tumor blood vessels as a marker of tumor progression in primary human uveal melanoma: a matched case-control study. 142 57

Genetic studies have implicated the early involvement of a gene on chromosome arm 9p in the development of cutaneous melanoma. We have performed loss-of-heterozygosity studies to confirm these original findings and identify the most frequently rearranged or deleted region of 9p. Eight markers were analyzed, including (from 9pter to proximal 9q) D9S33, the beta-interferon (IFNB1) locus, the alpha-interferon (IFNA) gene cluster, D9S126, D9S3, D9S19, the glycoprotein 4 beta-galactosyltransferase (GGTB2) gene, and the argininosuccinate synthetase pseudogene 3 (ASSP3). Two or more of these loci were found to be hemizygously reduced in 12 of 14 (86%) informative metastatic melanoma tumor and cell line DNAs, and homozygous deletions of the marker D9S126 were observed in 2 of 20 (10%) melanoma cell lines. These findings have resulted in the identification of a small critical region of 2-3 megabases on 9p21 in which a putative melanoma tumor-suppressor gene appears likely to reside. Several 9p candidate genes, including IFNB1, the IFNA gene cluster, GGTB2, and the tyrosinase-related protein (TYRP) locus, have all been eliminated as potential targets because they are located outside of the homozygously deleted regions.
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PMID:Homozygous deletions within human chromosome band 9p21 in melanoma. 143 46

Cytokines are soluble mediators involved in cell-cell regulations in the immunological and the hematopoietic systems-genetic engineering now allows the characterization and the availability of recombinant molecules, some of them being recently introduced in clinical trials. Interleukin-2 (IL-2) is the first factor having demonstrated a reproducible therapeutic effect on human metastatic solid tumors, mainly chemo-resistant. High-dose IL-2 alone could achieve about 25% objective responses in metastatic renal cancers, with a low but significant number of complete, relatively long-lasting complete responses. Similar data are obtained in metastatic melanoma. IL-2 is probably acting through the activation of cytotoxic lymphocytes (LAK: lymphokine activated killers). The interest for simultaneous administration of autologous LAK cells generated through in vitro culture with IL-2 is discussed. Cytokine therapy is currently limited by important systemic toxicities, including mainly general symptoms with fever, and a capillary leak syndrome with weight gain, edema and functional renal failure-cardiac are respiratory troubles can be life-threatening. Future trends for cytokine therapy will be: The discovery of new cytokines, and a better knowledge of their synergies, allowing the design of rational associations. A letter understanding of the mechanisms of toxicities, allowing specific prevention of adverse effects not needed for efficient anti-tumor action. Gene therapy, which will lead to important and prolonged release of cytokines by the tumor cells themselves, or by infiltrating peri-tumoral cells, in order to achieve local efficacy and to circumvent systemic toxicities.
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PMID:[Immunotherapy: current problems and outlook]. 146 35

In the diagnosis of melanocytic skin tumors, the assessment of the overall architectural pattern (silhouette) is often essential. We have previously shown by a computer simulation model that tumor patterns are likely to depend on the relative degrees of proliferation and motility of the tumor cells. In this study, we examined the morphological pattern of 12 cases each of nevocellular nevi, primary melanoma, and metastatic melanoma by image analysis. The patterns of the individual melanocytic skin tumors were compared statistically with patterns generated by computer simulation, which facilitates estimates of biological properties of the tumor cells. Additionally, mitotic counts were made to measure tumor cell proliferation. A comparison of the three diagnostic groups revealed that the cells of nevocellular nevi show a low degree of motility, which, however, still exceeds the very low degree of proliferation. Thus, an "invasive" pattern with numerous small nests and single cells at the base of the lesion is common. In primary malignant melanoma, tumor cell motility and tumor cell proliferation are significantly increased in various proportions, thus leading to varying morphological patterns. In metastatic melanoma, a strikingly elevated degree of proliferation exceeds the only slightly elevated degree of motility and leads to sharply demarcated, "expansive" lesions. To check the validity of the technical procedure, estimates of proliferation based on pattern analysis alone were compared with the results obtained by mitotic counts. There was a significant correlation, indicating that the assumptions of the computer model and the image analysis procedure are in fact applicable to real-life melanocytic skin tumors.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Relationship of tumor cell motility and morphologic patterns. Part 1. Melanocytic skin tumors. 151 Feb 20

Flavone acetic acid (FAA) showed impressive effects against murine solid tumours but no activity in clinical studies. The mechanism of action in mice may involve damage to tumour vasculature or immunomodulation, and these effects may be species-specific. Alternatively, concentrations of FAA achieved in mouse tumours may be higher than in human tumours. It is important to resolve this issue since it raises important questions about the relevance of in vitro versus in vivo tumour screens and the development of FAA analogues. As part of a Cancer Research Campaign Phase II study of metastatic melanoma in which 8.4 g m-2 FAA was given as a 6 h infusion, six tumour biopsies were obtained from four patients. FAA tumour concentrations were determined by HPLC and compared with subcutaneous murine solid tumours within the same analytical laboratory. Tumour/plasma percentages (range 26-61%; mean +/- SD, 43.9 +/- 11.4%) were similar to those in mice, as was the area under the curve (AUC) extrapolated to infinity and the AUC above the putative activity threshold of 100 micrograms ml-1. We conclude that the exposure of drug-refractory human melanoma tissue to FAA was comparable to that of sensitive mouse tumours. This suggests that reduced penetration of FAA into human tumours is unlikely to explain the lack of antitumour activity observed in clinical studies and that differences in mechanism of action are predominant.
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PMID:Tumour concentrations of flavone acetic acid (FAA) in human melanoma: comparison with mouse data. 152 May 97


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