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C G Hilders

Publications and source records attributed to C G Hilders.

9 recordsLinked to original sources
PubMed1996

Association of allele-specific HLA expression and histopathologic progression of cervical carcinoma.

Immunohistochemical studies have shown that loss of HLA expression is observed in cervical carcinomas but not in premalignant CIN lesions, indicating that downregulation of HLA is linked to tumor progression. The present study was performed to investigate whether the degree of HLA expression in cervical cancer correlates with more advanced disease as defined by histopathological features. Frozen tissue sections from 49 patients with squamous carcinoma of the cervix FIGO stage IB to IIB were stained with HLA class I monomorphic, locus- and allele-specific monoclonal antibodies. Histological data indicative of local disease, i.e., depth of invasion, tumor size, stage, and systemic spread of the disease, such as tumor-positive lymph nodes, were collected by reviewing the histological slides. Univariate analysis revealed that loss of HLA-A locus and A2-allele expression showed a positive, significant correlation with both presence of tumor-positive lymph nodes (P = 0.04 and 0.02, respectively) and the number of lymph nodes involved (both P = 0.04). These results strongly support the idea that, specifically in an immunogenic cancer type such as cervical cancer, tumor cells escape immunosurveillance and gain growth advantage by allele-specific downregulation of the HLA-A2 molecule. In view of the development of immunotherapeutical interventions in cancer, upregulation of HLA class I molecules may prove to be a useful additional tool in the combat against immunogenic tumors.

Alleles↗
PubMed1996

HLA expression and tumor-infiltrating immune cells in uveal melanoma.

BACKGROUND: In uveal melanoma, both the amount of tumor-infiltrating cells and the level of expression of HLA antigens are quite variable. We hypothesized that low levels of HLA expression lead to a lack of antigen presentation, which might prevent proper immunologic recognition of the tumor. This lack of recognition might subsequently lead to low levels of tumor-infiltrating cells. METHODS: To test this hypothesis, we determined the type and number of tumor-infiltrating cells in tumor sections from 24 uveal melanomas. We applied monoclonal antibodies directed against different types of immune cells and compared the results with the expression of HLA class I and class II antigens on the tumor cells. RESULTS: Infiltrating immune cells were observed in all uveal melanomas (although in small amounts), with a predominance of T lymphocytes. Significant positive correlations were observed between the number of CD3+ cells (T lymphocytes) and monomorphic HLA class I expression, allele-specific HLA-A2 and Bw4 expression, and HLA class II expression. Furthermore, the number of CD4+ cells (T helper cells, monocytes/ macrophages) and of CD11b+ cells (monocytes/macrophages) was significantly correlated with the level of monomorphic HLA class I expression. CONCLUSION: These data support our hypothesis that low levels of HLA expression (and therefore a lack of presentation of tumor-specific antigens) may lead to a low level of tumor infiltrate.

Adult↗
PubMed1995

Altered HLA expression by metastatic cervical carcinoma cells as a factor in impaired immune surveillance.

The altered expression of histocompatibility leukocyte antigens (HLA) in the development to cervical carcinoma suggests that tumor progression may be related to impaired recognition by host immune defense mechanisms. To investigate whether this phenomenon plays a role in the process of metastasis of cervical cancer, we analyzed and compared the HLA expression with the number of infiltrating immune cells in primary cervical carcinoma and related autologous metastases (n = 30) by staining serial paraffin and corresponding frozen sections with a panel of monoclonal antibodies. In 60% of the cervical metastases, compared to 21% of the primary tumors, a downregulation of monomorphic HLA class I antigens was observed, with frequent allele-specific alterations. In 50% the HLA class II expression was slightly increased on the metastatic tumor cells in comparison to the primary tumor. In addition, variability of alterations in HLA expression was observed between different metastases in the same patient. A minor infiltration of immune cells was present in cervical metastases compared to the primary tumors, especially in the HLA class I-downregulated metastases. Furthermore, loss of HLA class I expression on the metastatic tumor cells resulted in a significant decrease of tumor-infiltrating CD8+ T lymphocytes. These findings suggest that in cervical carcinoma loss of HLA class I expression plays a decisive role in the escape from immune surveillance leading to a greater metastatic potential of tumor cells.

Adult↗
PubMed1994

Isolation and characterization of tumor-infiltrating lymphocytes from cervical carcinoma.

The evidence that virus-induced tumors generally elicit T-cell responses prompts the notion that HPV-related cervical carcinoma would be amenable to treatment by T-cell-mediated adoptive therapy. Therefore, we cultured and cloned tumor-infiltrating lymphocytes (TIL) from a patient with cervical carcinoma and studied the in vitro characteristics of these TIL by using the established autologous tumor-cell line. After stimulation of bulk TIL cultures with 1,000 Units/ml recombinant interleukin 2 (rIL-2), followed by limiting dilution, T-cell clones were generated in the presence of 20 U/ml rIL-2 and irradiated autologous tumor cells, PBLs and EBV-transformed B-cell lines. Phenotypically, all clones were CD3/CD8-positive with a heterogeneous CD56 expression. All expressed preferential cytolytic activity against autologous tumor cells, did not lyse autologous lymphoblasts, and were cytotoxic against the NK-sensitive cell line K562. A minor lytic capacity was detectable on allogeneic cervical tumor-cell lines or tumor-cell lines of other histologic types. Cytotoxicity against the autologous tumor could be inhibited by anti-CD3, anti-CD8 and anti-ICAM1 but not by anti-HLA class-1 (W6/32, B9.12.1), anti-allele-specific HLA determinants and anti-LFA-3 antibodies. We demonstrate a highly specific autologous lytic activity of cervical carcinoma TIL, in which a CD3-associated surface antigen recognition is involved. These results may prove useful in further studies on adoptive immunotherapy of cervical cancer patients.

Adult↗
PubMed1994

The expression of histocompatibility-related leukocyte antigens in the pathway to cervical carcinoma.

The major histocompatibility complex probably plays a crucial role in the efficacy of the cellular immune response against virally infected cervical diseases. Therefore, the allele-specific histocompatibility-related leukocyte antigens (HLA) class I and II expression on normal (n = 10), premalignant (n = 25), and malignant cervical tissue (n = 30) was investigated. No alterations in monomorphic or locus/allele-specific HLA class I or II expression were observed in normal and premalignant epithelial tissue. In cervical carcinomas, however, a reduced expression of HLA class I antigens was present in 70% of the cases, comprising a monomorphic class I loss in 20%, and an allele-specific loss in 50% of HLA-A2-, 66% of A3-, 56% of Bw4-, and 37% of Bw6-positive patients. De novo expression of class II antigens was observed in 80% of the cervical carcinomas, with the sublocus products being expressed in the order HLA-DR > HLA-DQ > HLA-DP. The authors' results show that alteration in HLA expression is a process confined to malignant cells, which may allow tumors to evade immune surveillance. In addition, these findings have to be considered as new strategies of immunotherapy using cytotoxic T lymphocytes are developed.

Alleles↗
PubMed1993

Tinnitus suppression by intravenous lidocaine in relation to its plasma concentration.

In a double-blind controlled trial in nine patients with tinnitus we measured the lidocaine plasma concentrations during and after intravenous administration of lidocaine or placebo and scored the level of tinnitus on a visual analog scale. No patient showed any effect during the placebo infusion. Administration of lidocaine resulted in total suppression or suppression to a non-annoying level of tinnitus in five patients, slight suppression but still annoying tinnitus in two patients, and worsening tinnitus in one patient. No effect of lidocaine was observed in one patient. Most relief was obtained at plasma concentrations between 1.5 and 2.5 micrograms/ml. In this concentration range a significant (p < 0.05) effect of lidocaine on tinnitus was observed. However, notable side effects were observed at plasma concentrations greater than 2.0 micrograms/ml. The effect persisted until plasma levels of about 0.5 microgram/ml were reached. A large variability in the effects existed because of variations in lidocaine kinetics and because of the presumed psychologic components of tinnitus.

Adult↗
PubMed1993

Association between HLA-expression and infiltration of immune cells in cervical carcinoma.

BACKGROUND: To determine the degree of specificity of the cellular immune response in cervical carcinoma, that is known to be human papillomavirus-related, we investigated the exact relationship between in situ tumor-infiltrating immune cells and the monomorphic/allele-specific HLA expression on the tumor cells. EXPERIMENTAL DESIGN: Attention was focussed on the type, location and number of in situ immunocompetent cells in malignant cervical tissue (N = 30). Immune cell distribution was quantitatively assessed by morphometry for stromal and tumor tissue separately. These results were related to the degree of expression of monomorphic- and allele-specific HLA I and II antigens on the cervical tumor cells. RESULTS: In monomorphic HLA class I downregulated cervical tumors, a significant decrease in tumor-infiltrating CD8+ T cells was observed. However, allele-specific downregulation of respectively HLA-A2, HLA-A3, HLA-Bw4, and HLA-Bw6, did not correlate significantly with a decrease in tumor-infiltrating immune cells. For HLA class II-positive cervical tumors, HLA-DR expression significantly correlated with an increase in the presence of tumor-infiltrating CD3+/CD4+/CD8+ T cells, CD56+ natural killer cells and CD16+ macrophages. No significant correlations were found between alterations in HLA class I or II expression on the tumor cells and stromal infiltrating immune cells. CONCLUSIONS: Our observations provide in situ immunomorphologic evidence that in cervical carcinoma, de novo expression of HLA class II antigens on the tumor cells resulted in an increase of tumor-infiltrating immune cells. In addition, the tumor-infiltrating CD8+ T lymphocytes correlated with monomorphic HLA class I expression on the tumor cells, which stresses the existence of a HLA-restricted immune response of T lymphocytes in cervical carcinoma. These findings might have implications for the biologic behavior of this disease and have to be taken into account in strategies concerning immunotherapy of cervical carcinoma.

Carcinoma↗
PubMedDate not supplied

Vestibular investigations in acoustic neuroma.

Forty-eight patients with surgically proven acoustic neuroma were examined preoperatively with a comprehensive battery of vestibular tests. In 87% of the patients, reduced caloric responses were measured on the side of the lesion. In 60% of the patients a non-responsive labyrinth was found. Spontaneous nystagmus was observed in 29% of the patients. A significant correlation with the size of the tumour was found in the occurrence of abnormal saccades in the calibration test, pathological smooth pursuit movements and the occurrence of gaze nystagmus, respectively. There was no correlation between the magnitude of the caloric response reduction and the mean hearing loss, which suggests that the hearing loss and the vestibular function loss do not occur synchronously. This study shows that in most cases of acoustic neuroma, the peripheral part of the vestibular system is severely disturbed. Abnormalities in the central and peripheral part of the vestibular system are more easily recognized with increasing tumour size. We conclude that a complete battery of vestibular tests is essential in combination with audiometric, neurologic and radiologic analysis for the early clinical diagnosis of acoustic neuroma.

Caloric Tests↗