Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0025202 (melanoma)
 69,561 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Specific intracytoplasmic organelles, annulate lamellae and radial cisternae, have been studied in several human tumours. Annulate lamellae are observed in all cases of leiomyoma, leiomyosarcoma, rhabdomyosarcoma and malignant melanoma, whereas radial cisternae are only found in a case of leiomyosarcoma. Annulate lamellae are characterized by stacks of parallel arrayed long cisternae showing alternative arrangement of annuli and sacs. Some of these cisternae are connected directly with rough-surfaced endoplasmic reticulum and there is continuity with the lumen and membrane. Radial cisternae are mainly composed of two structures: numerous short cisternae, which are a variant of annulate lamellae, and numerous spherical particles derived from the cisternae. The cisternae are arranged parallel or radially around particles measuring up to 1100 A in diameter. These particles consisting of an amorphous high electron dense material without distinct limiting membrane are organized in groups and vary in number. There is no evidence of a direct relationship between these structures and viral infection.
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PMID:Fine structural study of annulate lamellae complexes in human tumors. 85 Oct 30

We reported recently that a novel immunomodulator, 7-thia-8-oxoguanosine (7T8OG)2 inhibited formation of pulmonary melanoma metastases (1), prevented against viral infection in mice (2) and potentiated the efficacy of a weakly immunogenic leukemia vaccine (3). Since certain tumor metastases and virus infected cells are targets to natural killer cells (NK cells), we now investigated whether 7T8OG is capable of activating NK cells in mice using NK cell sensitive YAC-1 and B16 and NK cell insensitive P815 targets. CBA/CaJ spleen cells incubated in vitro with 7T8OG at concentrations ranging from 0.005 to 0.5 mM responded with increased NK cell activity (32-62%) compared to controls (4-8%) to YAC-1 targets. Similar levels of augmentation in NK cell activity were observed when 40-168 mg/kg of 7T8OG was administered in vivo. In addition to the spleen, 7T8OG activated NK cells in the bone marrow (BM), the lungs, the liver, and in peritoneal exudate cells (PE). Although 7T8OG elicited activation of NK cells was observed as early as three hours after treatment, the maximal activity was observed after 24 h in the spleen; 12 h in the BM; 48 h in the lungs, and 72 h in PE. Administration of the drug by s.c., i.v., and i.p. routes all induced activation of NK cells in spleen, BM and PE. 7T8OG was found to activate NK cells in seven inbred and an outbred mouse strain, suggesting that the induced cytotoxicity against allogeneic and syngeneic tumor cells is not strain specific as well as independent of MHC restriction. C3H/He, CBA/CaJ and BDF/1 displayed higher levels of increased NK cell activity, whereas AKR mice were low responders. Low concentrations of IL-2 (0.25-5 U/ml) that induce little or no NK cell activity, when used in combination with 7T8OG, elicited significant enhancement of NK cell cytotoxicity. In contrast, IFN and 7T8OG showed no such synergism.
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PMID:Immunomodulatory activity of a novel nucleoside, 7-thia-8-oxoguanosine: I. Activation of natural killer cells in mice. 159 50

Methotrexate (MTX), 6-thioguanine (6-TG) and cytosine arabinoside (ara-C) inhibited the replication of adenovirus (viral capacity) more in drug-sensitive than in resistant human melanoma cell lines. By comparison, inhibition of cellular DNA and RNA synthesis after short treatment periods (less than 48 hr) was not a good predictor of cellular sensitivity. MTX, an inhibitor of de novo nucleotide synthesis, was most effective when added to cells just before infection with virus and inhibited viral capacity at doses 10-1000-fold lower than those required to affect cell survival. The MTX-sensitive cell lines, members of a DNA repair deficient group sensitive also to killing by methylating agents (the Mer- phenotype), were not deficient in dihydrofolate reductase but exhibited DNA fragmentation after treatment with MTX for 48 hr. 6-TG and ara-C, inhibitors of purine and pyrimidine salvage, were most inhibitory to viral capacity when added greater than 36 hr before virus infection and were less effective than MTX (doses 5-7-fold and 4-24-fold higher than for cell survival respectively). No correlation was found between MTX sensitivity and sensitivity to 6-TG or ara-C. These results indicate that (i) inhibition of viral capacity is a more comprehensive test of antimetabolite cytotoxicity than inhibition of cellular DNA or RNA synthesis; (ii) the viral capacity assay correctly predicts cellular sensitivity to MTX, 6-TG and ara-C and therefore has potential for application to primary cultures of human tumours; and (iii) MTX-sensitive cell lines and adenovirus replication rely heavily on de novo nucleotide synthesis, which in Mer- cells appears to be linked to a DNA repair defect as yet undefined.
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PMID:Effects of antimetabolites on adenovirus replication in sensitive and resistant human melanoma cell lines. 168 77

Interferons (IFN) are potent antiviral, cytostatic-cytotoxic and immunomodulatory agents. Although gene technology has made available an unlimited supply of all different kinds and types of IFN, their basic modes of action have not been clarified up to now. The therapeutic effects proven differ gradually between the individual disease entities. They comprise prophylaxis, prevention of recurrences and direct therapeutic effect, either of reducing the actual disease symptoms, or of inducing a complete recovery. For the following viral diseases a positive therapeutic effect has been shown: infections by herpes-viruses (herpes simplex keratitis , herpes zoster, herpes simplex), cytomegalovirus infections, chronic-hepatitis B virus infection, acute respiratory virus infections by rhino-, corona- and influenza viruses. Especially for the group of virus-associated tumors and papillomas, IFN is considered to be therapeutically effective. IFN has been accepted to be the first line treatment for laryngeal papillomatosis. In condylomata acuminata too, IFN is a potent therapeutic agent. Moreover, IFN represents the most effective therapeutic modality for Kaposi's sarcoma in patient with AIDS. Hairy cell leukemia, malignant lymphoma, multiple myeloma, melanoma and hypernephroma are the malignancies, for which a therapeutic effect of IFN could be proven. Furthermore, IFN is considered to be the therapy of first choice for hairy cell leukemias. Although there are some signs, that IFN could be a potent agent for adjuvant therapy, this question can not be answered - not even on principle - because of lacking sufficient data so far. Up to date, the therapeutic efficacy of IFN seems to be established only for hairy cell leukemia, laryngeal papillomatosis, Kaposi's sarcoma in patients with AIDS and partly for condylomata acuminata. For all other indications, first of all, sufficient phase-II-study data will have to be evaluated, before prospectively controlled studies, comparing the IFN treatment results with placebo and standard therapy results, can be initiated for the individual disease entities. Then, it will be possible to assess the therapeutic efficacy of IFN. Already now, IFN represent a valuable enrichment of the therapeutic modalities for malignancies and viral diseases.
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PMID:[Current status of interferon therapy]. 242 97

The question of whether the steroidal components in oral contraceptives (OCs) may have an initiating or promotional influence on the development of cancer continues to be raised as a public health issue. It is estimated that since the introduction of OCs nearly 25 years ago, more than 150 million women have used 1 or more types of the formulation and nearly 1 billion woman-years of exposure to the steroids have accumulated. Contraceptive practice in Australia would indicate that about 25% of women of reproductive age are using OCs. The debate about the OC's carcinogenic potential has recently been reopened with 2 reports in "The Lancet" of an association between the incidence of breast and cervical cancer and OC usage. Biologically the relationship between the contraceptive steroids and cancer must continue to be regarded as the most important concern with the longterm use of OCs. The demonstration of receptors to these steriods in these organs, in both normal and malignant tissues, further increases the speculation that the steroid hormones have a biological role in carcinogenesis in these target organs. Theoretical reasons exist for the concern about carcinogenesis and contraceptive steroids. This paper reviews the available evicence. Data can be derived only from large-scale epidemiological research, by means of case-control or cohort studies. No clear evidence exists that OCs cause or increase the chance of developing any cancer in the female genital tract and the breast. In fact, OC offers a significant protection against the development of endometrial and ovarian cancer, especially to those women who have taken OCs for a long time. The association between the risk of breast cancer and OC use is less certain, but factors such as the history of benign breast disease, a close relationship with breast cancer, or nulliparity -- previously considered to be important -- do not appear to contribute significantly to the risk. The weight of evidence indicates that no increased risk of breast cancer exists, even in those younger women aged less than 25 years who decide to use OCs before their 1st full-term pregnancy. There is some evidence that suggests that the risk of cervical neoplasia -- dysplasia, carcinoma-in-situ and invasive carcinoma -- may increase slightly in OC users but the actual part played by the patient's sexual history under these circumstances remains to be defined. There is now strong evidence to implicate multiplicity of sexual partners and wart virus infection in carcinogenesis of the uterine cervix. There does not appear to be an overall relationship between OCs and malignant melanoma. Overall, the evidence is reassuring. The low-dose combined OC can be considered safe, not only in terms of cardiovascular and thromboembolic risks, but also in relation to carcinogenesis.
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PMID:Cancer risks and the contraceptive pill. What is the evidence after nearly 25 years of use? 351 57

Murine peritoneal macrophages harvested 3-4 days after IP injection of vaccinia virus lysed S91-melanoma tumor cells in vitro; enhanced tumoricidal activity was measured with effector macrophages prepared 5-6 days after vaccinia virus infection. Treatment of virus-elicited macrophages prepared from DBA/2 mice with anti-asialo-GM1 antiserum, anti-Thy 1.2 antiserum or anti-Iad antiserum in the presence of complement so that cells sensitized with antibodies were lysed, did not reduce the measured level of tumoricidal activity indicating that macrophages [Ia(-); asialo GM1(-)] and not natural killer cells [asialo GM1(+); Thy 1.2(+/-)] or T-cells [Thy 1.2(+)] were responsible for mediating the lysis of S91-melanoma tumor cells. When incubated with virus-elicited macrophages but not thioglycollate-elicited macrophages, the ability of S91-melanoma tumor cells. to synthesize DNA was completely blocked. The results of these experiments support the view that one aspect of antitumor immunity enhanced during immunotherapy with vaccinia virus is the activation of macrophages which have cytolytic as well as cytostatic effects on melanoma tumor cells.
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PMID:Infection of DBA/2 or C3H/HeJ mice by intraperitoneal injection of vaccinia virus elicits activated macrophages, cytolytic and cytostatic for S91-melanoma tumor cells. 373 Dec 5

Specific active tumor immunotherapy methods offer the possibility of increasing the immunogenicity of tumor cells. One of these methods is viral oncolysis, in which tumor cells are modified by viral infection. We prepared vaccinia melanoma oncolysates (VMO) from human melanoma lines infected with vaccinia virus. In a preliminary trial at Washington University, sera from 12 patients with melanoma with stage I and II disease were obtained before and during treatment with VMO. The reactivity of these sera to melanoma lines was examined with a Staphylococcus protein A assay that detects most human IgGs. Our data demonstrate that, during treatment with VMO, sera from all 12 patients developed reactivity to melanoma lines. Selected sera were also tested in a double blind study by the C3-mixed hemadsorption assay, which detects mostly IgM. Results from this assay were in complete agreement with those obtained by the Staphylococcus protein A assay: Pretreatment sera were generally negative and sera obtained during treatment were positive. The specificity of these responses is presently under investigation. Our findings indicate that, as a consequence of treatment with VMO, a reactivity develops in the patients' sera. This reactivity is probably due to both IgG and IgM antibodies and its directed toward antigens expressed on human melanoma lines.
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PMID:Serologic response to human melanoma lines from patients with melanoma undergoing treatment with vaccinia melanoma oncolysates. 609 Dec 87

We investigated whether the rosetting of B-lymphoblastoid cell lines (B-LCL) by peripheral blood lymphocytes (PBLs) reflected possible interactions between lymphoid cells and immature cells of the hematopoietic system. Rosette formation could be blocked by the addition of soluble antigen extracted from B-LCL or blasts obtained from patients with acute myelogenous leukemia (AML). This inhibition was specific for AML blasts (similarly extracted material from melanoma lines had no inhibitory effect) and for the B-LCL receptor (leukemic extracts had no effect on surface receptors for sheep red blood cells (E) or antibody-sensitized red blood cells (EA)). The B-LCL receptor is present on leukemic Sezary T-cells as well as normal T-cells and its sensitivity to various enzymatic treatments is markedly different from that of E and EA receptors. In addition, B-LCLs derived from in vitro EB-viral infection of a normal donor's B lymphocytes were significantly rosetted by that donor's autologous PBLs. These data suggests the B-LCL receptor, present on mature T-cells, can recognize self determinants on myeloblasts and B-LCL. Further investigation will determine whether this interaction can affect the function of rosetted target cells.
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PMID:Peripheral blood lymphocytes with receptors for a determinant common to B-lymphoblastoid cell lines and acute myelogenous leukemia blasts. 620 38

The role of natural killer (NK) cells in tumor growth and metastasis was studied in syngeneic normal and beige inbred C57BL/6 mice. Mice with the beige point mutation have been shown to be deficient in nonstimulated NK activity. Tumor-passaged B16 malignant melanoma cells were refractory to NK activity as determined by in vitro assay, but after in vitro culture they became sensitive to NK activity. The NK-insensitive B16 tumor grew and metastasized similarly in normal and beige mice. However, the NK-sensitive B16 tumors grew more slowly and produced fewer metastases in normal mice than in NK-deficient beige mice. Activation of NK cells by lymphocytic choriomeningitis virus infection decreased the rate of growth and number of metastases of both NK-sensitive and NK-insensitive tumors in both normal and beige mice. These results suggest the importance of NK cells as a determinant of tumor growth and metastasis.
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PMID:Role of natural killer cells in tumor growth and metastasis: C57BL/6 normal and beige mice. 693 63

We have examined the ability of melanoma cell lines and normal human melanocytes, which have demonstrable intact IFN genes, to secrete both IFN-alpha and IFN-beta in response to induction with virus. Normal melanocytes were found to secrete both IFN-alpha and IFN-beta after virus induction. In contrast, although all but one of the melanoma lines tested were capable of secreting IFN-beta, none were capable of IFN-alpha secretion. This phenomenon was not due to defects in either translation of IFN-alpha mRNA or secretion of IFN-alpha proteins, since transfection of melanoma lines with a constitutive IFN-alpha 2b expression vector resulted in the secretion of high levels of IFN. On further examination, this inability to express natural IFN-alpha appeared to be due to a defect in activation of the IFN-alpha promoters, since constructs containing the IFN-alpha promotor were completely unresponsive to viral infection in melanoma cells but inducible in melanocytes. These results show that there is a specific disruption of IFN-alpha gene activation rather than IFN-beta in melanoma lines and suggest that this is due to disruption of a trans-acting IFN-alpha gene transcription factor. Disruption of this factor and its consequences may be important in the development of malignant melanoma.
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PMID:Interferon system defects in human malignant melanoma. 766 86


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