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F X Real

Publications and source records attributed to F X Real.

107 records · Page 6Linked to original sources

Kaposi's sarcoma and the acquired immunodeficiency syndrome: treatment with high and low doses of recombinant leukocyte A interferon.

The efficacy of recombinant leukocyte A interferon (rIFN-alpha A [Roferon-A, Hoffman-La Roche, Nutley, NJ]) treatment of Kaposi's sarcoma in patients with acquired immunodeficiency syndrome was evaluated in sequential trials using high doses (36 X 10(6) units) and low doses (3 X 10(6) units) of interferon. A major response was seen in 38% of patients treated at the high dose, with a median response duration of 18 months. At the low dose, the major response rate was 3%; dose escalation to 36 X 10(6) units resulted in an additional major response rate of 17% in low-dose nonresponders, with a median response duration of 10 months. Four of 11 patients who achieved a complete response remain free of disease, whereas all partial responders have shown disease progression. Unacceptable toxicity occurred in 27% of patients initially treated at the high dose and only in 10% of those who had progressive dose escalation up to 36 X 10(6) units. Prior opportunistic infections correlated negatively with therapeutic response, whereas large tumor burden and gastrointestinal involvement did not. Responding patients showed a significantly longer survival and a lower incidence of subsequent opportunistic infections than nonresponders. However, from our study we cannot determine whether rIFN-alpha A has an effect on the natural history of Kaposi's sarcoma in patients with the acquired immunodeficiency syndrome.

Acquired Immunodeficiency Syndrome↗

Immunological variables as predictors of prognosis in patients with Kaposi's sarcoma and the acquired immunodeficiency syndrome.

Multivariate analysis was used to identify which of a large number of pretreatment immunological parameters correlated with therapeutic response, subsequent development of opportunistic infection, and survival from the time of diagnosis in a group of 70 patients with Kaposi's sarcoma and acquired immunodeficiency syndrome treated with recombinant leukocyte A interferon. In a logistic regression model, delayed type hypersensitivity response to one or more recall antigens and high proliferative response to Escherichia coli were significant predictors for response to recombinant leukocyte A interferon (for the model, P = 0.01). For prediction of the development of opportunistic infection, the model selected low proliferative responses to phytohemagglutinin and E. coli (P less than 0.001). Favorable factors predicting survival in the Cox regression model were the absence of endogenous serum interferon activity and a high proliferative response to E. coli (P less than 0.001). The estimated median survival for the group with endogenous serum interferon activity and low E. coli response was 12 months; the median has not yet been reached for the group with no serum interferon and a high E. coli response. We conclude that immunological parameters may be useful in predicting prognosis in patients with Kaposi's sarcoma and acquired immunodeficiency syndrome.

Acquired Immunodeficiency Syndrome↗

Expression of epidermal growth factor receptor in human cultured cells and tissues: relationship to cell lineage and stage of differentiation.

Mouse monoclonal antibodies have been used to study the distribution of the epidermal growth factor receptor in human cultured cells and tissues. As expected, most epithelial cells expressed epidermal growth factor receptor (EGFr), whereas cells of hematopoietic origin were EGFr-. However, EGFr was found to be differentially expressed on cultured cells of neuroectodermal origin. Normal melanocytes and a proportion of melanomas are EGFr-, whereas a distinct subset of other melanomas, astrocytomas, and neuroblastomas is EGFr+. Expression of the EGFr in melanomas was closely related to the expression of phenotypic traits of differentiation. Less differentiated melanomas have an epithelioid morphology and are nonpigmented, Ia+, and EGFr+; in contrast, more differentiated melanomas have a dendritic morphology and are pigmented, Ia-, and EGFr-. In the melanoma cell panel used, expression of EGFr did not correlate with rate of proliferation. Expression of EGFr in tissues also showed a lack of correlation with the proliferative state of cells. Our findings indicate that expression of EGFr is related to cell lineage and specific stages of cellular differentiation, rather than only to cell proliferation. The data suggest that receptor content may be elevated in a large number of tumor cell lines.

Antibodies, Monoclonal↗

Serological response of melanoma patients to vaccines prepared from VSV lysates of autologous and allogeneic cultured melanoma cells.

Melanoma patients were vaccinated with cell-free lysates prepared from vesicular stomatitis virus (VSV)-infected cultured autologous and allogeneic melanoma cells. Eleven patients received vaccines produced from the melanoma cell line SK-MEL-13. This cell line, derived from the melanoma of Patient AH, expresses a differentiation antigen (initially defined by autologous antibody) that is restricted to melanomas and other cells of neural crest origin (an example of a Class 2 melanoma antigen). Thirteen patients received vaccines prepared from autologous melanoma cells, the only known source of autologous unique (Class 1) melanoma antigens. VSV lysates were used for vaccination because VSV infection of tumor cells has been shown to augment the immunogenicity of tumor antigens. All patients but one vaccinated with VSV lysates of autologous melanoma cells developed antibodies against VSV, and all patients vaccinated with VSV lysates of SK-MEL-13 developed antibodies against HLA-related antigens. Antibodies against a Class 1 (unique) melanoma antigen were detected in only one case, and antibodies against Class 2 (shared) melanoma antigens were not found in any of the patients. The authors conclude that VSV lysates of melanoma cells are not effective in increasing the serologic response of melanoma patients to Class 1 or 2 melanoma antigens.

Adult↗

Treatment of Kaposi's sarcoma and thrombocytopenia with vincristine in patients with the acquired immunodeficiency syndrome.

Kaposi's sarcoma occurs in about one third of patients with the acquired immunodeficiency syndrome. Although in some patients the tumor is principally a cosmetic problem, other patients have progressive disease with significant morbidity. Twenty-three patients with Kaposi's sarcoma related to the acquired immunodeficiency syndrome were treated with vincristine. Three patients had a coexisting immune thrombocytopenia. Of the 18 patients evaluable for response, 11 had a partial response and 7 had a minor response. The median duration of partial response was 4 + months. All 3 thrombocytopenic patients developed a significant increase in platelet count, which in 2 was sustained with continued treatment for 6 and 9 months, respectively. We conclude that vincristine has antitumor activity in the epidemic form of Kaposi's sarcoma and that it is also effective in the treatment of associated immune thrombocytopenia.

Acquired Immunodeficiency Syndrome↗

Unexpected toxicity from radiation therapy in two patients with Kaposi's sarcoma receiving interferon.

Two homosexual men with Kaposi's sarcoma and acquired immune deficiency received radiation therapy to the oral mucosa while treatment with recombinant leukocyte A interferon was being given systemically at a dose of 36 million units. Symptoms of radiation mucositis developed after the administration of 900 rad in the first patient and 1,050 rad in the second patient. Radiation therapy had to be stopped after doses of 1,100 and 2,100 rad, respectively, had been given. Both patients had to be admitted to the hospital for supportive care and the second patient required placement of a feeding tube. To our knowledge, no other clinical observations suggesting interactions of radiation therapy and interferon have been reported. We discuss the results of experiments with cultured cells and experimental animals which suggest that such interactions occur and may be successfully exploited therapeutically.

Acquired Immunodeficiency Syndrome↗

Surface antigens of melanomas and melanocytes defined by mouse monoclonal antibodies: specificity analysis and comparison of antigen expression in cultured cells and tissues.

Mouse monoclonal antibodies (mAb) detecting 13 distinct systems of surface antigens on cultured melanocytes and melanomas were tested for reactivity with panels of (a) normal and malignant cultured cells; (b) normal adult and fetal tissues; and (c) specimens of metastatic melanoma and other tumor types. The objectives of this study were to compare antigen expression in cultured versus noncultured cells, to develop a panel of mAbs that identify subsets of melanomas, and to provide requisite information about antibody specificity in preparation for the use of antibodies in the diagnosis, imaging, and therapy of melanoma. Five of the melanoma surface antigens have been well characterized biochemically [GD3, chondroitin sulfate proteoglycan, HLA Class II antigens, glycoprotein of molecular weight 130,000 (gp130), and glycoprotein Mr 95,000/protein Mr 97,000 (gp95/p97)]. Three antigens have been related to melanocyte differentiation (HLA Class II, M111/M231, and M144), and six provide additional markers for subsets of cultured melanomas. mAb R24 reacts with the disialoganglioside GD3, a predominant ganglioside on cultured melanoma cells and other cells of neuroectodermal origin. A high proportion of melanoma, astrocytoma, and sarcoma tissue specimens were GD3+. In normal tissues, reactivity of mAb R24 was restricted to melanocytes, neuronal and glial cells in the central nervous system, parotid gland, adrenal medullary cells, and rare cells in the connective tissue. mAb B5 detects a chondroitin sulfate proteoglycan that is expressed by most melanoma and astrocytoma cell lines and by cultured melanocytes. Most of the melanoma and astrocytoma specimens were B5+, whereas other tumor types tested were B5-. mAb 13-17, which detects a monomorphic determinant of HLA Class II antigens, reacted with melanomas, and with a variety of other cancers, but not with normal skin melanocytes. There is considerable variability in the expression of GD3 and HLA Class II antigens in individual melanoma specimens; cotyping for these two antigens showed no evidence for coordinate expression. mAb L101 detects gp130 and mAb L235 detects gp95, antigens that are strongly expressed on a broad range of cultured cell types. In contrast to their wide distribution on cultured cells, gp130 expression in tissues was generally restricted to a subset of melanomas and some normal cells, and gp95 was detected on only a small number of melanomas. mAb M111/mAb M231 and mAb M144 define intermediate and late stage differentiation markers of cultured melanocytes and melanomas.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

Class 1 (unique) tumor antigens of human melanoma. Identification of a 90,000 dalton cell surface glycoprotein by autologous antibody.

Analysis of the humoral immune response of patients with melanoma has identified a small group of individuals with antibody to cell surface antigens that are restricted to autologous melanoma cells. These antigens, referred to as Class I or unique tumor antigens, are demonstrated by reactions between serum and cultured melanoma cells from the same patient and absorption tests with autologous and allogeneic normal and malignant cells to determine antibody specificity. Five Class 1 melanoma antigens have been defined to date, but insight into the nature of these antigens has been limited because antibodies identifying these antigens lacked detectable immunoprecipitating activity. We have now defined a Class 1 melanoma antigen (designated FD) that is immunoprecipitated by autologous antibody. FD antigen is identified by an IgG antibody present in the sera of patient FD, and peak titers of this antibody in tests with cultured autologous melanoma cells are in the range of 1:2048. By absorption tests, FD antigen could not be detected on any other cell type, including 33 allogeneic melanomas. Prolonged culture of FD melanoma cells resulted in decreased expression of FD antigen, but sublines could be obtained with stable antigen expression. FD antigen is trypsin and heat sensitive, neuraminidase resistant, and is shed in the culture medium. Immunoprecipitation of 125I-labeled cell membrane preparations revealed a 90,000 dalton component of pI 5.5. Serum immunoprecipitating activity could be absorbed by autologous melanoma cells but not by autologous B cells or allogeneic cell lines. A component of the same molecular mass could be precipitated from lysates of cells metabolically labeled with [3H]mannose. The membrane form of the FD antigen binds strongly to Con A-Sepharose and can be eluted with methyl-alpha-D-mannoside. The identification of a precipitating Class I antigenic system of melanoma facilitates efforts to generate monoclonal antibodies to this tumor antigen and to clone its coding sequence.

Absorption↗

American cancer society Phase I trial of naturally produced beta-interferon.

Naturally produced beta-interferon was evaluated following i.m. and i.v. administration to 18 patients with advanced cancer. Fever (mean +/- S.E. = 38.1 degrees +/- 1.7 degrees), enhancement of natural killer cell cytotoxicity, and depression of the white blood cell count occurred following a single i.m. injection in the absence of detectable serum antiviral activity. Fever, rigors, and fatigue were dose-limiting toxicities following daily i.v. administration of 10 million units. Tachyphylaxis, as reported following repetitive administration of alpha-interferons, did not occur. Side effects, depression of the white blood cell count, and enhancement of natural killer cell cytotoxicity were similar when beta-interferon was administered daily as a 10-min bolus or as a 6-hr infusion. However, while natural killer cell cytotoxicity increased progressively over 10 days of bolus injections, it was maximal after the initial 6-hr infusion of beta-interferon. Administration of 10 million units of beta-interferon divided equally between a 10-min bolus injection and a 3-hr infusion was well tolerated and resulted in high initial peak and lower sustained serum interferon levels. Based on pharmacokinetic criteria, this schedule of administration can be recommended for further study in Phase II trials. However, in light of the biological activity of beta-interferon following i.m. administration, the level of beta-interferon in the serum may have limited value as a predictor of antitumor response, toxicity, or biological response modification.

American Cancer Society↗

Protein p53 and inducer-mediated erythroleukemia cell commitment to terminal cell division.

Inducer-mediated murine erythroleukemia cell (MELC) differentiation provides a model for examining factors determining terminal cell differentiation. The nuclear protein, p53, has been implicated as a potential determinant of cell cycle progression and cell differentiation. In this study p53 content and synthesis, during inducer-mediated MELC differentiation, has been examined with monoclonal antibodies to p53. A decrease in p53 synthesis and content was demonstrated during induced differentiation. As determined by cell cycle fractionation, the decrease in p53 is manifest at all stages of the cell cycle. Hemin, which induces globin mRNA accumulation but not terminal cell division, fails to decrease p53 content. A MELC variant resistant to inducer-mediated commitment to terminal cell division also fails to decrease p53 levels in response to inducers. These experiments suggest that p53 is implicated in MELC cell proliferation and that an induced decrease in p53 may be responsible for G1 phase prolongation and terminal G1 arrest.

Acetamides↗

Analysis of two new leukemia-associated antigens detected on human T-cell acute lymphoblastic leukemia using monoclonal antibodies.

Two monoclonal antibodies (anti-3-3 and anti-3-40) were produced, which identify two new leukemia-associated antigens. Both antibodies reacted with most cell lines derived from patients with T lymphoblastic leukemia (T-ALL), but were not detected on suspensions of normal hematopoietic cells (including thymocytes) by cytotoxicity, absorption, or indirect immunofluorescence assays. Analysis of fresh leukemic cells indicated that anti-3-3 only reacted with T-ALL cells, while anti-3-40 also reacted with some non-T, non-B ALL cells and a few acute myelocytic leukemia (AML) cells. The 3-40 antigen was also found histopathologically in frozen sections of several normal tissues, including the epithelial cells and a few lymphoid cells of the thymus, and some malignant tissues. The 3-3 antigen was not found in any tissue studied. A "double absorption"assay provided additional serologic evidence that the two antibodies identify different antigenic determinants. Biochemical analysis indicated that the molecules immunoprecipitated by anti-3-3 and anti-3-40 have molecular weights of 35,000-40,000 daltons. This study demonstrated that the 3-3 and 3-40 antigens are markers for human T-ALL and can be used along with the normal T-lymphocyte antigen, 3A1, to discriminate T-ALL from cutaneous T-cell lymphoma (CTCL), adult T-cell leukemia (ATL), and T-cell chronic lymphocytic leukemia (T-CLL).

Adult↗

Serum concentrations of organochlorine compounds and K-ras mutations in exocrine pancreatic cancer. PANKRAS II Study Group.

BACKGROUND: Organochlorine compounds such as 1,1,1-trichloro-2,2-bis(p-chlorophenyl)-ethane (p,p'-DDT), 1,1-dichloro-2,2-bis(p-chlorophenyl) ethylene (p,p'-DDE), and some polychlorinated biphenyls (PCBs) are carcinogenic to animals and possibly also to human beings. Occupational exposure to DDT may increase the risk of pancreas cancer. The high frequency of K-ras mutations in pancreatic cancer remains unexplained. We analysed the relation between serum concentrations of selected organochlorine compounds and mutations in codon 12 of the K-ras gene in patients with exocrine pancreatic cancer. METHODS: Cases were prospectively identified in five hospitals. Mutations in K-ras were analysed by PCR and artificial restriction fragment length polymorphism. Cases of pancreatic cancer with wild-type K-ras (n=17) were frequency matched for age and sex to cases of pancreatic cancer with a K-ras mutation (n=34, case-case study). These 51 cases were further compared with 26 hospital controls (case-control comparison). Serum organochlorine concentrations were measured by high-resolution gas chromatography with electron-capture detection and negative ion chemical ionisation mass spectrometry. FINDINGS: Serum concentrations of p,p'-DDT were significantly higher in pancreatic cancer cases with a K-ras mutation than in cases without a mutation (odds ratio for upper tertile 8.7 [95% CI 1.6-48.5], p for trend=0.005). For p,p'-DDE the corresponding figures were 5.3 (1.1-25.2, p for trend=0.031). These estimates held after adjusting for total lipids, other covariates, and total PCBs. A specific association was observed between a glycine to valine substitution at codon 12 and both p,p'-DDT and p,p'-DDE concentrations (odds ratio 15.9, p=0.044 and odds ratio 24.1, p=0.028; respectively). A similar pattern was shown for the major di-ortho-chlorinated PCBs (congeners 138, 153, and 180), even after adjustment for p,p'-DDE, but without a specific association with spectrum. Concentrations of p,p'-DDT and p,p'-DDE were similar among wild-type cases and controls, but significantly higher for K-ras mutated cases than for controls (p<0.01). INTERPRETATION: Organochlorine compounds such as p,p'-DDT, p,p'-DDE, and some PCBs could play a part in the pathogenesis of exocrine pancreatic cancer through modulation of K-ras activation. The results require replication, but they suggest new roles for organochlorines in the development of several cancers in human beings.

Aged↗