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S Prescott

Publications and source records attributed to S Prescott.

At least 37 records · Page 2Linked to original sources
PubMed1995

Interleukin-6 production by bladder tumors is upregulated by BCG immunotherapy.

PURPOSE: To determine whether BCG therapy could upregulate interleukin-6 (IL-6) production in human transitional cell carcinomas (TCC). MATERIALS AND METHODS: Immunohistochemistry of tumor biopsies and urinary cytospins and ELISA studies of urine from bladder cancer patients and TCC cell-line supernatants, before and after exposure to BCG, were performed. RESULTS: Constitutive staining for IL-6 was found in the majority of bladder tumors. Interleukin-6 was detected in the urine of all 13 patients with carcinoma in situ and increased 5-fold during BCG therapy. Levels were variable but were greater in nonresponders (p < 0.01). During therapy both detached bladder urothelial cells and polymorphonuclear leukocytes stained for IL-6. Production of IL-6 increased in only 3 cell lines after exposure to BCG, but all 7 cell lines showed increases after exposure to interferon-gamma (p = 0.015). Grade 3 cell lines showed much greater upregulation than grade 1 and 2 cell lines. CONCLUSIONS: The increase in IL-6 during BCG therapy may be caused by urothelial cells as well as leukocytes. The higher levels seen in nonresponders may be due to either higher grade or persisting tumor.

BCG Vaccine↗
PubMed1995

Changes in urinary cytokines and soluble intercellular adhesion molecule-1 (ICAM-1) in bladder cancer patients after bacillus Calmette-Guérin (BCG) immunotherapy.

Intravesical immunotherapy for carcinoma in situ of the bladder is arguably the most effective form of tumour immunotherapy described to date. Following repeated instillations of BCG organisms into the bladder, large quantities of cytokines are detected in patients' urine. This study concerns the production of IL-1 beta, IL-2, IL-4, IL-6, IL-8, IL-10, tumour necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma) and soluble ICAM-1 (sICAM-1) throughout the six weekly instillations which comprise a therapeutic course. Sequential instillations of BCG induced secretion of IL-1 beta, IL-2, IL-6, IL-8, IL-10, TNF-alpha, IFN-gamma and sICAM-1 into urine. The responses were heterogeneous between patients and cytokines, but some general trends were evident. Although cytokine levels were initially low, their concentration increased with repeated instillation of BCG. Certain cytokines (e.g. IL-6, IL-8 and IL-10) could be detected after the first instillation, whilst others (e.g. IL-2 and IFN-gamma) were not detected until after the third or fourth instillation. Interestingly, IL-4 was not detected, perhaps suggesting a differential effect on Th2-like responses. Some patients produced particularly elevated or non-detectable levels of cytokines, and a positive correlation was found between the production of various cytokines. The production of a particular cytokine did not correspond with lack of production of another species. Whether monitoring the production of cytokines following therapy may be of prognostic value will be determined in a larger series of patients. However, as these potent immunomodulators are thought to be important for the 75% complete clinical response observed with BCG therapy, there remains the possibility that detection of the products of an activated immune system may correlate with eventual clinical outcome. This study is a necessary forerunner to full prognostic evaluation of such immunological data.

BCG Vaccine↗
PubMed1994

Autocrine regulation of ICAM-1 expression on bladder cancer cell lines: evidence for the role of IL-1 alpha.

We have studied the autocrine regulation of essential expression of the intercellular adhesion molecule-1 (ICAM-1) on 8 transitional cell carcinoma (TCC) cell lines (histopathological grades 1-3). The constitutive expression of ICAM-1 was regulated by soluble factors in an autocrine fashion. These factors were produced by all cell lines, with the exception of the MGH-U1 cell line. The effects observed could be largely attributed to IL-1 alpha. However, the residual ICAM-1 inducing activity (up to 30% of ICAM-1 induction) could not be associated with any known ICAM-1 inducers (IFN gamma, TNF alpha, TNF beta, IL-1 alpha, IL-1 beta, IL-4, retinoic acid, LPS). In contrast to recombinant derived cytokines, the IL-1 alpha present in tissue culture supernatant was only able to induce ICAM-1 on high-grade tumours and not low-grade cells. This discriminative effect is similar to that noted following in vitro culture of tumour cells with bacillus Calmette-Guerin organisms. Whether the production of soluble factors (e.g., IL-1 alpha) by TCC cell lines plays an essential autocrine role for bladder tumours and/or affects the interaction with cells of the immune system needs to be investigated further.

Antigens, CD↗
PubMed1994

Emergence of early region 1-containing replication-competent adenovirus in stocks of replication-defective adenovirus recombinants (delta E1 + delta E3) during multiple passages in 293 cells.

Early region 1 (E1)-deleted human adenovirus (AV) recombinants have been shown to be powerful tools of gene transfer in vivo and in vitro and are considered for application in human gene therapy. We could detect increasing titers of E1-containing adenovirus in two independent E1 + E3-deleted recombinant AV stocks during multiple passages in 293 cells, most likely due to a recombinant event with the host cell genome. We show the deleterious effects of this E1-containing, mostly replication-competent AV subpopulation in vivo and compare different screening methods of AV stocks for its detection. These considerations are important for the safety of human gene therapy trials.

Adenovirus E1 Proteins↗
PubMed1994

Intravesical Evans bacille Calmette-Guérin for carcinoma in situ of the urinary bladder. Scottish Urological Oncology Group.

OBJECTIVE: To study the long-term results of a single 8 week course of intravesical Evans bacillus Calmette-Guérin (BCG) on carcinoma in situ (CIS) of the urinary bladder. PATIENTS AND METHODS: This study reports on 43 patients who each received a single 8 week course of intravesical BCG. RESULTS: In spite of the good initial complete response rate of 70%, the long-term follow-up was disappointing with half the patients either having recurrence or progression of their disease by 2 years. The patients had a close follow-up protocol with early radical treatment when disease progressed. The cause specific survival at 5 years was 70%. CONCLUSION: We feel that similar future treatment protocols without maintenance treatment are not justified.

Administration, Intravesical↗
PubMed1993

The immunomodulatory effects of urine from patients with superficial bladder cancer receiving intravesical evans BCG therapy.

Bladder cancer cells were stimulated with urine obtained from patients with superficial bladder cancer who had received treatment using intravesical bacillus Calmette-Guérin (BCG). The urine from the first 12 h following each of six BCG instillations was collected and examined for its biological effect. We evaluated effects that had previously been attributed to cytokines detected in the urine of such patients. The modulation of MHC class II antigen and intercellular adhesion molecule-1 (ICAM-1) expression were studied. Using neutralizing polyclonal antibodies to interferon gamma and tumour factor alpha the relative contribution of these molecules to the effects investigated were determined. When cells were stimulated for up to 48 h with first-instillation urine, little effect was seen in any of the parameters investigated. Urine from the sixth instillation, however, proved to be a potent immunomodulatory agent, inducing MHC class II molecule and ICAM-1 expression. Urine from instillations two to five mediated increasing immunomodulatory effects. When sixth-instillation urine samples were treated with neutralizing antibodies to interferon gamma prior to their addition to the bladder cancer cells, a marked and significant decrease in their potency was observed. Only in urine from one patient did any immunomodulatory capability remain after antibody treatment. Neutralizing antibodies to tumour necrosis factor alpha, however, failed to reduce the ability of any patient's urine to induce ICAM-1 expression. When both antibodies were used simultaneously no further decrease in potency was observed. These studies demonstrate for the first time the potential immunomodulatory and cytotoxic effects of urine produced by patients receiving intravesical BCG. Furthermore, in all samples tested, the major immunomodulatory component was shown to be interferon gamma. Although tumour necrosis factor alpha is produced as a result of BCG therapy, this cytokine did not appear to contribute to the parameters investigated, namely the induction of HLA class II antigens, and cell-surface ICAM-1.

BCG Vaccine↗
PubMed1993

The effect of recombinant cytokines on bladder cancer cells in vitro.

We have studied the Major Histocompatibility Class II-modulating and antiproliferative actions of recombinant interferon-gamma, tumor necrosis factor-alpha, interleukin-1 alpha, interleukin-2 and granulocyte macrophage-colony stimulating factor on bladder cancer cells in vitro. Indirect immunofluorescent staining employing monoclonal antibody probes in conjunction with flow cytometric analysis and tritiated thymidine incorporation assays were used. Interferon-gamma was a strong inducer and enhancer of class II antigens. Tumor necrosis factor-alpha could not induce the expression of class II antigens on tumor cells, which were initially class II-negative, but enhanced the expression on cells which already demonstrated low levels of the antigen. Interleukin-1, interleukin-2 and granulocyte macrophage-colony stimulating factor did not affect the major histocompatibility class II expression. Interferon-gamma and tumor necrosis factor-alpha both demonstrated powerful anti-proliferative effects on the bladder cancer cells, particularly those derived from low grade tumors (G1 and G2). Interleukin-1 alpha had no effect on tumor cell proliferation. In contrast interleukin-2 and granulocyte macrophage-colony stimulating factor had significant stimulatory effects on the proliferation of the low grade tumor cells (G1).

Antigens, Neoplasm↗
PubMed1992

Expression of adhesion molecules by bladder cancer cells: modulation by interferon-gamma and tumour necrosis factor-alpha.

The constitutive expression by eight human bladder cancer cell lines of the cell adhesion molecules intercellular adhesion molecule-1 and intercellular adhesion molecule-2 was studied using monoclonal antibody probes in conjunction with flow-cytometry. Tumour lines of low grade (G1) did not constitutively express intercellular adhesion molecule-1, rather they were found to express intercellular adhesion molecule-2. The G2 cells expressed no intercellular adhesion molecule-2, however, a low percentage did express intercellular adhesion molecule-1. High grade cells (G3) only expressed intercellular adhesion molecule-1 on their cell surface but at higher levels than the G2 cell line. Exposure of the bladder cancer cell lines to interferon-gamma induced and augmented the expression of intercellular adhesion molecule-1 by all except one of the cell lines (UMUC3). Intercellular adhesion molecule-2 expression remained unaltered. The modulation of intercellular adhesion molecule-1 expression was dependent on the concentration of interferon-gamma and the duration of stimulus. De novo intercellular adhesion molecule-1 expression, induced by interferon-gamma, was rapid (< 4 hours) with only a short period of stimulation being required (< 10 seconds). The rapid increase in expression of intercellular adhesion molecule-1 required de novo protein synthesis and was not the result of release of intercellular adhesion molecule-1 from an intracellular pool. Interferon-gamma and tumour necrosis factor-alpha were found to act synergistically in the induction and augmentation of intercellular adhesion molecule-1 expression. Optimal induction occurred with 10 Uml-1 of both molecules. These results suggest a correlation between constitutive adhesion molecule expression and the histopathological grade of the tumour. The implications of these findings for Bacillus Calmette Guerin and interferon-gamma immunotherapy of bladder cancer is discussed.

Carcinoma, Transitional Cell↗
PubMed1992

An investigation of factors influencing the in vitro induction of LAK activity against a variety of human bladder cancer cell lines.

We investigated the sensitivity of transitional cell carcinoma cells, derived from the human bladder, to lymphokine activated killer cells. Recombinant interleukin-2 activated peripheral blood mononuclear cells were studied for their ability to mediate the cytolysis of a panel of four established human bladder transitional cell carcinoma cell lines. Lymphokine activated killer activity was assessed using a standard four hour chromium release assay. All four bladder cancer cell lines proved to be susceptible to lymphokine activated killer mediated cytolysis. This was found to be dependent upon the dose of cytokine and upon the duration of the activation period. The four cell lines were differentially susceptible to lysis (specific cytotoxicity at effector to target ratio of 40:1; RT112 = 22.9%, RT4 = 49.2%, MGH-U1 = 49.1%, EJ18 = 62.3%). The varying susceptibility of lymphokine activated killer mediated cytotoxicity was found to be independent of the histological grade of the parent tumour or the donor of effector cells. Both interferon-alpha and tumour necrosis factor-alpha also elicited lymphokine activated killer cell activity, although the maximum specific cytotoxicity achieved was considerably lower than that obtained with interleukin-2 alone. Interleukin-2, at optimal concentration, and tumour necrosis factor-alpha were found to behave synergistically in the generation of lymphokine activated killer effectors. However, concentrations of tumour necrosis factor-alpha higher than 100 Uml.-1 resulted in a decrease in specific cytotoxicity. These findings suggest a possible use of adoptive immunotherapy in human bladder cancer and indicate the optimum conditions for the generation of such effector cells.

Carcinoma, Transitional Cell↗
PubMed1992

The inhibitory effects of interferon gamma on the growth of bladder cancer cells.

The inhibitory effect of interferon-gamma on the growth of three human bladder cancer cell lines, RT4, RT112 and MGH-U1, representing tumour grades 1, 2 and 3 respectively, was studied. The effects of 10, 100 and 1000 Uml.-1 of interferon-gamma on cell numbers and thymidine incorporation were measured at 24 hour intervals up to a maximum of seven days. Morphological appearances were also studied. Each line was susceptible to the growth inhibitory effects of interferon-gamma and this was both dose and time dependent. The effects of interferon-gamma, on the RT4 and RT112 cells were apparent from 24 hours, and were both cytostatic and cytotoxic in nature, whereas the effects on MGH-U1 cells were seen from 48 hours onwards and were only cytostatic. Cytological changes occurred in all three cell lines, being most pronounced in RT112. The growth of bladder cancer cells was inhibited by interferon-gamma, and in this study high grade tumour cells were least sensitive.

Carcinoma, Transitional Cell↗
PubMed1992

Intravesical Evans strain BCG therapy: quantitative immunohistochemical analysis of the immune response within the bladder wall.

Previous studies have demonstrated that is is the local immune response which is of importance for the anti-tumour activity of BCG therapy. We have investigated this by quantitative immunohistochemical analysis of serial bladder mucosal biopsies taken before, during and after an eight week course of intravesical Evans strain BCG therapy and three monthly thereafter in 16 patients (15 extensive CIS and one extensive G2pTa papillary tumour). This particular group of patients had a 67% complete response rate at six months post-treatment. The main findings on immunohistochemical analysis were the universal induction of MHC Class II antigens by urothelial cells which was statistically significant up to 6 months after completion of therapy, coupled with a T cell dominated cystitis. Increases in CD3+ T cell infiltration of the lamina propria and that of the CD4+ "Helper" subset which predominated were significant up to 3 months post-therapy and these cells showed evidence of increased immunological activation as shown by increased interleukin-2 receptor and MHC Class II antigen expression. There were also significant increases in CD68+ macrophage and the incidence of CD22+ B cell aggregates but CD57+ NK cells were sparse both before and after therapy. The degree of mononuclear cell infiltration for all markers examined (except CD57) was significantly greater in those biopsies in which the urothelial cells expressed MHC Class II antigens than in those that did not. Also the degree of T cell infiltration (CD3, CD4 and CD8) was significantly greater in the eight patients deemed to have had a complete response compared to those seven with a partial response or treatment failure. These results are discussed in terms of possible mechanisms of action for BCG therapy and in particular the role of enhanced antigen presentation by tumour cells.

Administration, Intravesical↗
PubMed1992

Role of adhesion molecules in lymphokine-activated killer cell killing of bladder cancer cells: further evidence for a third ligand for leucocyte function-associated antigen-1.

The lysis of eight human bladder cancer cell lines by lymphokine-activated killer cells (LAK) was found to be partially dependent upon the expression by the target cell of either intercellular adhesion molecule-1 (ICAM-1) or intercellular adhesion molecule-2 (ICAM-2). Using adhesion blockade studies these molecules were found to contribute towards sensitivity to lysis. Tumour lines of low grade (G1) did not constitutively express ICAM-1, but were found to express ICAM-2. High grade cells (G2, G3), however, only constitutively expressed ICAM-1 on their cell surface. Interferon-gamma (IFN-gamma) induced and augmented the expression of ICAM-1 by all except one of the cell lines (UMUC3) in a dose- and time-dependent manner. This was accompanied by an increased susceptibility to lymphokine-activated killer mediated cytolysis. Anti-ICAM-1 antibodies partially inhibited the increase in cell lysis due to IFN-gamma. However, this inhibition was not complete. When effector cells were treated with antibodies to leucocyte function-associated antigen-1 (LFA-1) the inhibition of lysis was greater and ranged from 72 to 96% with a mean of 87% inhibition. These results suggest that the increased sensitivity of IFN-gamma-treated bladder cancer cell lines to LAK cells is partially attributable to the induction of ICAM-1. However, blocking of ICAM-1 with antibodies could only partially inhibit the increased LFA-1-dependent lysis. This supports recent evidence for the existence of an additional ligand for LFA-1, other than ICAM-1 and ICAM-2.

Antigens, CD↗
PubMed1991

The effects of recombinant human interferon-gamma on a panel of human bladder cancer cell lines.

We have examined the Major Histocompatibility Complex class II antigen inducing capabilities of recombinant human interferon-gamma, on a panel of human transitional cell carcinoma lines which have been raised from original tumours of varying histological grades: RT4 (grade 1), RT112 (grade 2) and MGH-U1 (grade 3). Cells were examined for class II antigens using an indirect immunofluorescent staining method and analysed on a fluorescence activated cell sorter. Twenty percent of RT4 cells constitutively expressed class II antigen. Both RT112 and MGH-U1 were repeatedly found to be negative for this antigen prior to treatment with interferon-gamma. Following treatment with interferon-gamma all three lines showed an increase in class II antigen expression, which was consistently dependent on both the length of incubation and concentration of interferon-gamma. A differential susceptibility was found amongst the three cell lines which may relate to the histological grade of the parent tumor.

Carcinoma, Transitional Cell↗
PubMed1990

Radio-immunoassay detection of interferon-gamma in urine after intravesical Evans BCG therapy.

Our previous studies suggested that interferon-gamma (IFN gamma) was produced in the local immune response to intravesical BCG. To confirm this we modified a commercially available radio-immunoassay for detection of this lymphokine in urine. The urinary levels of IFN gamma were compared in serial urine samples taken from six patients undergoing treatment with Evans strain BCG and seven patients receiving intravesical mitomycin C/epirubicin. IFN gamma was detected consistently in response to BCG with levels reaching a peak (mean 67.1 U/ml., range 7.9 to 155.9 U/ml.) four to six hours post-instillation whereas after other intravesical agents no IFN gamma was detectable after seven of 13 instillations. After the remaining six instillations lower levels were detected (mean 7.4 U/ml., range 0.6 to 22.4 U/ml.). The difference in peak levels between the two groups was statistically significant (p less than 0.001 Mann Whitney U test). These results are further evidence of specific cellular immune activity in response to intravesical BCG therapy and suggest anti-tumour mechanisms similar to allograft rejection and autoimmunity.

Administration, Intravesical↗