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Biomedical subjects

R T Oliver

Publications and source records attributed to R T Oliver.

At least 109 records · Page 6Linked to original sources
PubMed1993

Immunological paradox in testicular tumours: the presence of a large number of activated T-cells despite the complete absence of MHC antigens.

Tissue sections from 22 seminoma (Se) and 10 teratoma (Te) patients were investigated for correlation between the presence of tumour infiltrating T-lymphocytes (TIL) and the expression of major histocompatibility complex (MHC) antigens using an immunoperoxidase staining technique. Complete absence of both class I and II antigens was observed in all Te and 20 out of 22 Se. The two positive Se showed only weak expression on 2% of tumour cells. Despite the absence of human leucocyte antigens (HLA) there were a large number of TIL scattered throughout the tissues in the case of Se with no predominance of CD4 or CD8 subpopulations in either group. T gamma positive cells were less than 5% of total CD3 positive cells in both Se and Te. The majority of the TIL were found to express activation markers, i.e. HLA class II antigens. Culture of tumour cell suspension with IL-2 produced passageable IL-2-dependent T cells from 10 out of 15 tumours. Studies with testis cell lines showed the complete absence of class I antigens in 2 out of 5 cases and the inability of interferon gamma (IFN gamma) to induce expression. IFN gamma also failed to induce class II antigens in three out of five of these lines. The immunological paradox of the presence of a large number of activated T-cells in testicular tumours despite the complete absence of MHC antigens remains unexplained and needs further investigation. Possible hypotheses are reviewed.

Histocompatibility Antigens Class I↗
PubMed1993

Intensity of class I antigen expression on human tumour cell lines and its relevance to the efficiency of non-MHC-restricted killing.

A modified tetrazolium reduction assay (MTT) was used to assess the relation between HLA class I antigen expression on tumour cells and their susceptibility as a target for non-MHC restricted LAK/NK cytotoxicity using interleukin-2 activated peripheral blood mononuclear cells (MNC) from normal individuals. At 20/1 effector/target ratio this ranged from no killing to 77%. The efficiency of killing was dependent on duration of effector cell culture with IL-2, peaking at day 10 and declining thereafter. This killing could be enhanced by addition of other cytokines including interferons alpha, beta and gamma. Study of a panel of 15 tumour cell lines using a single effector showed that there was no statistically significant inverse correlation (using Spearman rank test) between the degree of tumour class I expression and LAK/NK killing at 20/1 (r = 0.23 P = 0.39) and 10/1 (r = 0.30, P = 0.27) and at 5/1 E/T ratio r = 0.47, P = 0.08) respectively. Lack of inverse correlation between these two parameters came from study of one bladder tumour line (FEN), whose absent class I antigens had been corrected by transfection with beta 2 microglobulin gene. At high E/T ratio (20/1) there was an increase in the susceptibility of target cells to lysis (36% parent cell, 45% transfected cell), whilst at lower E/T ratios (1/1) there was significantly more killing of the non-transfected cells (10% vs 31%). The addition of anti-class I antibody W6/32 increased killing by 18% but this was non-specific as the same increase occurred with a class II antibody. These data suggest that overall there was not an inverse correlation between class I expression and LAK/NK killing at high E/T ratios, whilst at low (5/1 or lower) E/T ratios this correlation nearly reached statistical significance suggesting that the conflicting literature reports may be due to a threshold levels of effector cells above which the masking effects of MHC antigens disappears.

Antigens, Neoplasm↗
PubMed1993

Hurricane growth of malignant trophoblastic teratoma.

The case history of a 27 year old male ex-intravenous drug user who presented with haemoptysis and indistinct lung shadowing is reviewed. During a 3 week period of investigation his lung shadowing increased dramatically and it became apparent that he had metastases from chorionic gonadotropin-producing testis cancer which had undergone spontaneous regression of the primary tumour. Unfortunately by the time he was referred for treatment he was in respiratory failure and died 48 hours after treatment started. The critical importance of the urinary pregnancy test (available in most casualty departments to diagnose ectopic pregnancy) in accelerating diagnosis and treatment of such a case is highlighted.

Adult↗
PubMed1993

Does the rapid response to cisplatin-based chemotherapy justify its use as primary treatment for intracranial germ-cell tumours?

We reviewed presentation, diagnostic problems and outcome of eight cases of primary intracranial germ-cell tumour (4 germinoma, 4 teratoma) treated with Cisplatin-based chemotherapy at our centre over the last ten years. Three patients received primary chemotherapy with Cisplatin-based regimens followed by radiotherapy for subsequent relapse, two were treated with a combination of chemotherapy and external radiotherapy, and three received chemotherapy for relapse after radiotherapy. The response to Cisplatin-based chemotherapy was rapid, with some patents exhibiting symptomatic improvement within 24 h. Four patients achieved complete remission within 21 days, and three of these have remained progression-free. Four patients in total have survived for 32 to 128+ months. Six of seven patients tested pre-treatment had central diabetes insipidus and five had partial anterior pituitary failure. The endocrine deficit progressed in two, with no recovery in any patient. It is arguable that chemotherapy should be the primary therapy in all such cases diagnosed on the basis of tumour markers and imaging, with surgery and/or radiotherapy as later options. As these tumours are rare, such questions can only be answered by collaboration studies.

Adolescent↗
PubMed1993

Bladder and prostate cancer screening for human papillomavirus by polymerase chain reaction: conflicting results using different annealing temperatures.

Two sets of L1 ORF degenerative primers, GP5/6 and MYO9/11, have been used to screen for human papillomavirus (HPV) sequences in bladder tumours, cell lines and controls by polymerase chain reaction (PCR). None of the 14 bladder and prostate tumours or nine bladder cell lines contained HPV sequences when tested with L1 ORF primer pair GP5/6 at 40 degrees C annealing temperature. In contrast, use of the L1 ORF primer pair MY09/11 at this low annealing temperature consistently gave a 450 bp band, suggesting the presence of HPV. This occurred in all samples including the negative DNA controls. An increase in stringency to an annealing temperature of 55 degrees C resulted in an elimination of this band in the test and negative control samples. This finding may explain why there are contradictory reports in the literature, and further studies are in progress to clarify this issue.

Adult↗
PubMed1992

Bleomycin lung: the effect of different chemotherapeutic regimens.

A review of hard-copy computed tomography (CT) images of patients who had undergone chemotherapy for testicular teratoma revealed that the incidence of lung toxicity appeared to be lower in those who had received bleomycin by slow infusion [EBCi (3) regimen, etoposide/bleomycin/cisplatin] rather than by intravenous bolus [PVB regimen, cisplatin/vinblastine/bleomycin; BEP (5) regimen, bleomycin/etoposide/cisplatin]. This difference reached statistical significance only for PVB vs EBCi (3) (t = 2.63, P less than 0.01). Nevertheless, in view of continuing reports of mortality resulting from bleomycin-induced pulmonary fibrosis in patients receiving the drug by i.v. bolus, further exploration of these results is clearly justified.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1992

Phase I study comparing continuous infusion of recombinant interleukin-2 by subcutaneous or intravenous administration.

22 cancer patients entered a randomised phase Ib trial comparing the effects of low-dose recombinant interleukin-2 (300 micrograms/m2, approximately equivalent to 6.4 x 10(6) cetus units or 38 x 10(6) U per day) given continuously by intravenous or subcutaneous infusion. At 48 h after two 5-day courses, median lymphocyte levels (x 10(9)/l) were 6.0 (387% increase) in the subcutaneous arm (n = 9) and 5.9 (369% increase) in the intravenous arm (n = 8). Liver and renal toxicity were similar in the two groups. One minor response lasting 4 months occurred in 12 renal cancer/melanoma patients receiving subcutaneous treatment and one durable complete remission continuing at 30 months and one minor response lasting 10 months occurred in 6 renal cancer/melanoma patients receiving intravenous treatment.

Adult↗
PubMed1992

Induction of MHC antigens by tumour cell lines in response to interferons.

The induction of major histocompatibility complex antigens by interferons (IFN) on 17 established tumour cell lines was investigated by radio binding. One bladder (Fen) and two testis lines (Tera I and Ha) lacked class I antigens and IFN-gamma failed to induce their expression. However, IFN-gamma upregulated these antigens on lines expressing low class I antigens (Tera II and EP2102) with little or no significant effect on high class I expressing lines (T24 and RT112). In one bladder line (Wil) IFN-gamma, whilst failing to alter monomorphic class I, upregulated polymorphic HLA-A2 and A3 antigens. None of the 17 lines expressed class II antigens, but could all be induced by IFN-gamma except T24, TccSup, Tera II and Lan lines. This defect was not due to the absence of IFN-gamma receptor, since under the same conditions intracellular adhesion molecule 1 was upregulated. IFN-alpha, whilst failing to have any effect on class II, induced class I antigens. IFN-beta showed no activity on either class I or II antigens when used alone. However, in combination, it inhibited IFN-gamma induced class II antigens. Thus, it may be possible to study cells from fresh tumours to preselect the minority of patients who might benefit from cytokine therapy.

Antibodies, Monoclonal↗
PubMed1992

Pilot study to evaluate impact of a policy of adjuvant chemotherapy for high risk stage 1 malignant teratoma on overall relapse rate of stage 1 cancer patients.

A total of 41 patients with stage 1 malignant teratoma of the testis treated from January 1986 to June 1990 was entered into a pilot study of 2 courses of adjuvant cisplatin-based combination chemotherapy. Of the patients 22 had a high or intermediate risk of relapse according to the Medical Research Council (United Kingdom) prognostic factor analysis and surveillance was instituted for 19 patients with a low relapse risk. The overall relapse rate in this group of patients (median followup 2 years) was 9.7% (5% in the adjuvant group and 16% in the surveillance group), which was significantly better than the 35% rate in the historical series treated by surveillance from 1980 to 1985 and equaled or was possibly better than that reported from adjuvant retroperitoneal lymph node dissection. Justification for consideration of 1 course of adjuvant treatment for such cases is reviewed, and the need for examination of such an approach in a neoadjuvant setting with either lymph node dissection or surveillance is examined.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1992

Familial testicular cancer: a report of the UK family register, estimation of risk and an HLA class 1 sib-pair analysis.

Forty-two families with two or more cases of testicular cancer have been reported to the UK Register for Familial Testicular Cancer, comprising two pairs of identical twins, 27 sets of other brothers (25 pairs, two triples), nine father-son pairs, two pairs of first cousins and two uncle-nephew pairs. In total 91 testicular tumours are described in 86 individuals (42 (46%) pure seminoma, 49 (54%) other germ cell tumours). The median age at diagnosis in these patients was significantly younger than that in a comparable series of non-familial patients (29 c.f. 32.5 years, P less than 0.01). In a case-control comparison of 794 testicular cancer patients, eight patients (1.0%) had a brother and four patients (0.5%) had a father with a previous diagnosis of testicular cancer at the time of their own diagnosis (and these families are all included in this report). Two out of 794 controls (0.3%) had a first degree relative with testicular cancer. The cumulative risk to a brother of a patient for developing testicular cancer by the age of 50 years was estimated to be 2.2% (95% C.I. 0.6-3.8%) which results in a relative risk of 9.8 (95% C.I. 2.8-16.7) in comparison with the general population. HLA Class I typing of 21 affected sib-pairs demonstrated four (19%) sharing two haplotypes, 13 pairs (62%) sharing one and four pairs (19%) sharing none. This did not differ significantly from the expected proportions of 25%/50%/25%. It is unlikely, therefore, that there is a major gene associated with testicular cancer predisposition within or closely linked to the major histocompatibility gene complex on chromosome 6.

Adolescent↗
PubMed1992

T cell immune response to cancer in humans and its relevance for immunodiagnosis and therapy.

Review of the relationship between the degree of immunosuppression and malignancy in patients on immunosuppressive drugs or immunosuppressed by HIV infection, postoperative blood transfusion or pregnancy provides the most convincing evidence of the importance of intact T cell immunity in resistance to cancer. Defective HLA class I and II antigen expression on tumours arising in non-immunosuppressed individuals and correlation of these changes with increased malignancy and diminished TIL provide the most convincing evidence that one factor necessary to ensure survival of most spontaneous tumours is mutation that enables tumour cells to escape rejection by cytotoxic T cells. These changes are less frequent in tumours in immunosuppressed patients, and preliminary data suggest that use of cytokine therapy is more successful in these tumours and the one in five spontaneous tumours demonstrating normal expression of HLA antigens and high levels of T cell infiltration. These observations suggest that future use of this therapy should be focused on these cases. All modalities of cancer therapy except hormone therapy (ie surgery, radiotherapy and chemotherapy) suppress immune responses. Defects of HLA antigen expression are less marked in early cancer. Combinations of immunotherapy with conventional treatment at presentation, including hormone therapy in view of data demonstrating regeneration of the thymus after castration, needs further investigation. Preliminary results from randomized trials involving nearly 300 individuals accidentally exposed to carcinogens demonstrated nearly 60% reduction of incidence of malignancy at 5 years in the arm receiving non-specific immunotherapy. If confirmed, such an approach might be more cost-effective as an approach for cancer prevention than organ specific cancer screening or vaccination against cancer associated viruses such as hepatitis B or papillomaviruses.

Animals↗
PubMed1991

Paired tumour infiltrating lymphocyte (TIL) and tumour cell line from bladder cancer: a new approach to study tumour immunology in vitro.

This paper reports the first example of tumour infiltrating lymphocytes (TILs) and a tumour cell line from the same individual and analyses their characteristics. The tumour cell line (CAT), derived from a patient with well-differentiated (G3pTa) TCC, has been in culture for 24 months and subcultured more than 100 times. Epithelial origin was established by electronmicroscopy and use of a range of monoclonal antibodies (Mabs) against cytokeratins. The TILs isolated from the same tumour expressed all the phenotypic characteristics of normal activated T cells and demonstrated low levels of cytotoxicity against the autologous tumour line (CAT). Comparison of cell surface molecules of these cells revealed the loss of HLA-B7, B44 and Bw6 from the CAT cells whilst maintaining HLA-A2, A3 and Bw4. Karyotypic analysis demonstrated three rearranged chromosomes (between chromosomes 4 and 11, 10 and 13, 11 and 17) on CAT cells. The potential that study of paired autologous tumour cells and TILs in culture offers for studying the role of MHC antigens in tumour rejection and the impact of different approaches to correcting the defect are reviewed.

Antibodies, Monoclonal↗
PubMed1991

Correlation between class I antigen expression and the ability to generate tumour infiltrating lymphocytes from bladder tumour biopsies.

Analysis of tissue sections from transurethrally resected bladder tumours using anti-CD3 antibody showed the presence of T lymphocytes in intra-epithelial layers in eight of 12 cases investigated. In a larger group of patients, Tumour Infiltrating Lymphocyte (TIL) growth was established from six of 19 cases using Interleukin-2 (IL-2) and conditioned medium (CM) and resulted in the expansion of TILs up to 100-fold. TILs from these individuals were phenotyped with W6/32 (anti-HLA-A,B,C), HB55 (anti-DR) and anti-CD3 antibodies using FAC sorter. The mean +/- s.d. frequency of positive staining with these antibodies were 96.7 +/- 4.0%, 87.5 +/- 10.0% and 82.5 +/- 7.8% respectively, indicating the activated nature of these T cells. The cytotoxic activity of these TILs against Daudi (ie, LAK activity) cell line at 25/1 E/T ratios varied from 26.3 +/- 3.2 to 62.8 +/- 5.2%. In one case where TILs and autologous tumour cell line were established, cytotoxicity studies showed low level of cytotoxicity against the autologous tumour cells (15.8 +/- 1.6%) compared with 62.8 +/- 5.2% against Daudi. Staining of tumour sections from these 19 individuals with W6/32 and BBM.1 revealed positive staining in six of six that developed TILs but only six of 13 (46%) cases, whose tumour failed to grow TILs (P less than 0.02, Fisher exact test). These results are indicative of the presence of IL-2 passageable T cells in bladder cancer biopsy and demonstrate that the successful expansion of these cells correlates with the normal expression of class I antigens on the tumour cells.

Antigens, CD↗