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G D Chisholm

Publications and source records attributed to G D Chisholm.

At least 19 recordsLinked to original sources
PubMed1992

The distribution of PSA, cathepsin-D, and pS2 in BPH and cancer of the prostate.

In view of the limitations associated with the present tumor markers for prostate cancer, we have examined the potential expression of two further markers, Cathepsin-D and pS2, in human prostate and attempted to link their concentrations with the histopathology of the tissue, the PSA levels and the androgenic status of the gland. Cathepsin-D and pS2 were measured in cytosol fractions obtained from 22 patients with benign prostatic hyperplasia (BPH) and 20 patients with prostate cancer (CaP) employing immunoassays specific for these markers. The concentrations of Cathepsin-D (BPH: mean +/- SEM = 18.50 +/- 1.88 nmol/g protein; CaP = 19.75 +/- 2.49 nmol/g protein) and pS2 (BPH = 1,024.7 +/- 348.06 ng/g protein; CaP = 1,513.88 +/- 268.60 ng/g protein) were not different in the two tissue types, whereas PSA in BPH tissue (1,952.27 +/- 249.93 micrograms/g protein) was significantly higher than the measurements in CaP (583.75 +/- 104.33 micrograms/g protein). However, none of the tumor marker concentrations correlated with the degree of differentiation of the tumors, and we were unable to establish any correlation with the levels of testosterone and dihydrotestosterone in the tissue. In conclusion, although Cathepsin-D and pS2 are expressed in prostate tissue, it is doubtful whether they will have an active role in the management of prostate cancer.

Cathepsin D↗
PubMed1992

Expression of interferon-gamma receptors on bladder cancer cells: does it correlate with biological response?

Previously we have shown a differential biological response of three human bladder cancer cell lines (RT4, RT112 and MGH-U1) to gamma interferon (IFN-gamma). The present study examines the relationship between the biological response and the expression of the interferon-gamma receptor on the tumour cell surface. Using a competitive radioligand binding assay and Scatchard analysis, we measured the number and affinity of the IFN-gamma receptors on each of the above cell lines. Individual cells from each line expressed large numbers (29,100-41,800) of high-affinity receptors (kd = 2.4-3.9 x 10(10) M). There was no statistically significant difference in either of these parameters between the three lines. We therefore conclude that the biological response of these bladder lines to IFN-gamma does not relate to the number or affinity of its receptor on the plasma membrane of these tumour cells.

Carcinoma, Transitional Cell↗
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

Basaloid carcinoma of the prostate gland: histogenesis and review of the literature.

The clinicopathological features of a basaloid carcinoma of the prostate gland are described in a 28-year-old man, and the management and prognosis discussed. Basaloid tumours of the prostate are very rare and only a few cases have been described in detail. Those cases which have been reported as adenoid cystic carcinoma, adenoid cystic-like carcinoma and adenoid basal cell tumour are reviewed.

Adult↗
PubMed1992

Changes in detrusor innervation with relief of outflow tract obstruction.

In 10 patients with urodynamically proven outflow tract obstruction, detrusor biopsies were taken prior to and following relief of obstruction. The changes in detrusor innervation were compared following the relief of obstruction within the study group and also with an age-matched control group who were urodynamically normal. There was a significant reduction in detrusor innervation in the study group when compared with controls pre-operatively. Within the study group there was a significant increase in detrusor innervation in 8 patients following relief of outflow tract obstruction. Persistence of symptoms after prostatectomy may be explained by failure of detrusor reinnervation.

Aged↗
PubMed1992

Identification of metastatic disease by T category, gleason score and serum PSA level in patients with carcinoma of the prostate.

Pre-operative serum prostate specific antigen (Tandem-R assay), T category, Gleason score and the metastatic (M1) status of a consecutive series of 60 patients with newly diagnosed carcinoma of the prostate were studied prospectively. The results revealed that, of these variables, pre-operative serum PSA (greater than 100 ng/ml) was the single most important indicator of metastatic disease, with 100% predictive value. With this alone, 83.3% of M1 disease could be correctly identified. For the remaining 17%, however, we advocate a high index of suspicion if the tumour is T3-T4 category on digital rectal examination (predictive value = 71.4%) and has a high grade with a Gleason score 8-10 (predictive value = 81%).

Aged↗
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↗
PubMed1992

Radical radiotherapy with salvage surgery for invasive bladder cancer: results following a reduction in radiation dose.

The management of invasive bladder cancer in Edinburgh, as in many other centres in the UK, has been by radical radiotherapy, with cystectomy reserved for local treatment failure or relapse. A review of the results of this policy in 1987 highlighted what was felt to be an unacceptably severe morbidity rate of 15%. The dose of radiation was therefore reduced from 55 Gy in 20 daily fractions to 52.5 Gy. Forty of 80 patients (50%) treated in this way have achieved a complete response at 6 months which is a similar response rate to that in previous reports. In addition, ten of 23 frail or elderly patients (43%) achieved a complete response with a lower dose of 50 Gy given as a split course over 7 weeks. Eighteen patients have had a salvage cystectomy, and 12 of 18 (67%) are alive and disease-free. Although follow-up is short, to date toxicity has been reduced, and our results support our decision to reduce the radiation dose.

Adult↗
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↗
PubMed1991

Prognostic value of raised prostatic acid phosphatase and negative skeletal scintigraphy in prostatic cancer.

Of 438 consecutive cases of newly diagnosed prostate cancer, 178 (41%) had skeletal metastases (T0-4 M1) at the time of diagnosis according to skeletal scintigraphy; 139 men had serum prostatic acid phosphatase (PAP) greater than twice the upper limit of normal on 2 separate occasions at the time of diagnosis and 65% of them had metastases on bone scan. However, 49 men with normal bone scans were found to have similarly raised serum PAP. (Such patients are defined as having skeletal metastases in the current Medical Research Council immediate versus deferred orchiectomy study and stratified accordingly). The actuarial survival of this group was calculated by life table methods and was compared with that of 2 other subgroups: those patients having metastases demonstrated on bone scan, and those patients having both normal bone scans and normal serum PAP. The survival of the "metastatic by acid phosphatase" group was significantly better than that of the "metastatic by bone scan" group but did not differ from that of patients having both normal scans and PAP. For patients with no scintigraphic evidence of skeletal metastases at diagnosis, those with a raised PAP were at a significantly greater risk of scan conversion, although this was more powerfully predicted by high histological grade.

Acid Phosphatase↗
PubMed1991

Neoadjuvant chemotherapy with methotrexate and cisplatin prior to radiotherapy for invasive transitional cell carcinoma of the bladder. Assessment of feasibility and toxicity.

A prospective study has been performed to assess the feasibility and toxicity of administering neoadjuvant chemotherapy with methotrexate (200 mg/m2) and cisplatin (100 mg/m2) prior to radical radiotherapy. Twenty patients with advanced transitional cell carcinoma of the bladder were assessed after each of 3 courses of chemotherapy, after radiotherapy and 6 months following treatment. Of particular concern was whether neoadjuvant chemotherapy compromised the ability to give potentially curative radical radiotherapy, delayed effective palliation of distressing urinary symptoms, or allowed local tumour progression prior to definitive treatment. It was concluded that this chemotherapy regimen was well tolerated, did not compromise the ability to give radical radiotherapy and resulted in the prompt palliation of urinary symptoms. This treatment, however, did not stop the development or progression of metastatic disease in some patients. In only 1 patient was there local progression during chemotherapy.

Adult↗
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↗