Detection of T helper responses, but not of human papillomavirus-specific cytotoxic T lymphocyte responses, after peptide vaccination of patients with cervical carcinoma.

Human papillomavirus type 16 (HPV16)-encoded E7 oncoprotein is constitutively expressed in cervical carcinoma cells and is required for cellular transformation to be maintained. The E7 protein, therefore, forms an attractive target for T-cell-mediated immune intervention to prevent or treat HPV16+ tumors. The authors performed a peptide-based phase I/II vaccination trial to induce anti-tumor immune responses in patients with recurrent or residual cervical carcinoma. Fifteen HLA-A*0201+ patients with HPV16+ cervical carcinoma received vaccinations with synthetic peptides representing 2 HPV16 E7-encoded, HLA-A*0201-restricted cytotoxic T lymphocyte epitopes and a pan-HLA-DR-binding T-helper epitope, PADRE, in adjuvant. No signs of toxicity were observed. Two patients had stable disease for more than 1 year after vaccination, 3 patients died of the disease during or shortly after the vaccination period, and 10 patients maintained progressive cervical carcinoma. Specific immune responses directed against the vaccine components were analyzed in peripheral blood samples. No cytotoxic T lymphocyte responses against the HPV16 E7 peptides were detectable. After vaccination, strong PADRE helper peptide-specific proliferation was detected in 4 of 12 patients. In conclusion, peptide vaccination with 2 HPV16 E7 cytotoxic T lymphocyte epitopes and a universal T helper epitope is well tolerated by patients with advanced cervical carcinoma. Despite a reduction of in vitro cytolytic or proliferative recall responses to some, but not all, conventional antigens in this patient group, peptide-specific proliferative responses were induced in 4 patients. Based on the current study, it is now feasible to perform peptide vaccination in earlier stages of HPV16-induced cervical disease.

Presence of an eosinophilic infiltrate in cervical squamous carcinoma results from a type 2 immune response.

OBJECTIVES: The presence of an eosinophilic infiltrate in patients with cervical squamous carcinoma has been shown to correlate with a worse overall survival, suggesting a less effective immune response in these cases. Since type 2 cytokines such as IL-4 and IL-5 are known to attract eosinophilic granulocytes, an immunohistochemical study was performed to gain further insight as to whether a type 1 or type 2 immune response is involved in eliciting an eosinophilic infiltrate. MATERIAL AND METHODS: Frozen tissue sections of 9 normal cervical tissues, 23 premalignant cervical lesions, and 23 cervical squamous carcinomas were stained by immunohistochemistry with monoclonal antibodies directed against IFN-gamma and IL-4 as representatives of a type 1 or a type 2 response, respectively. RESULTS: Normal tissues and premalignant lesions of the cervix did not contain eosinophilic granulocytes and showed very few IL-4- and IFN-gamma-positive cells. In cervical carcinoma the presence of IL-4 on tumor infiltrating cells correlated with the presence of eosinophilic granulocytes in the tumor (P value <0.01) and stroma (P value <0.05). IFN-gamma-positive cells did not show any such correlation. In addition, colocalization was observed of CD3- and IL-4-positive T lymphocytes indicating that IL-4 production is mediated by T lymphocytes. CONCLUSION: The relative increase of IL-4-positive cells in the presence of an eosinophilic infiltrate might thus reflect an imbalance between a type 1 and type 2 response, in favor of the latter. Since a type 1 response stimulates an adequate cellular response which is negatively regulated by type 2 cytokines, these findings might explain the worse clinical outcome seen in cervical cancer patients with an eosinophilic tumor infiltrate. These results may have implications when developing immunotherapeutical strategies for cervical cancer.

Immunotherapeutic strategies for cervical squamous carcinoma.

Progress in developing preventive and therapeutic vaccines for HPV-associated diseases has been made in the last few years, but continued studies are needed to evaluate the clinical feasibility of different vaccination approaches and to determine a clinically effective and safe one. The perfect HPV vaccine will have both preventive and therapeutic capabilities, and because it is likely to be used world-wide, especially in developing countries, it must also have low production costs.

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.

Occasional memory cytotoxic T-cell responses of patients with human papillomavirus type 16-positive cervical lesions against a human leukocyte antigen-A *0201-restricted E7-encoded epitope.

Most cervical carcinoma (Cxca) cells constitutively express human papillomavirus type 16 (HPV16) E6 and E7 oncoproteins. These proteins are, therefore, attractive targets for T cell-based immunotherapy. Previously, we identified HVP16 E7-encoded CTL epitopes. In patients with cervical intraepithelial neoplasia or Cxca, little is known concerning T-cell activity against viruses in general and against HPV16 in particular. Here, we have screened the blood of 10 healthy donor controls and of 22 patients with HPV16+ cervical lesions for the presence of CTLs directed against HPV16 E7- and control influenza virus matrix-derived epitopes presented by HLA-A *0201. We detected influenza virus-specific CTLs in all donors and in the majority of patients, indicating that most patients have functioning T-cell responses despite their lesions or therapeutic interventions. Moreover, we show that patients with HPV16+ lesions occasionally have memory CTLs against a HPV16 E7-encoded epitope (sequence YMLD-LQPETT), providing evidence for natural CTL immunity against HPV16 in patients with cervical lesions. Combined, these findings raise possibilities for vaccination with HPV16 E7-encoded peptides to induce or augment CTL responses for treatment or prevention of Cxca.

Clinical relevance of various microscopical features of the second-look specimen in advanced ovarian cancer.

The second-look specimens of 70 patients with advanced ovarian cancer (FIGO 2B, 3, and 4) were reviewed and classified according to four categories: no response to chemotherapy (category a), predominantly histologically viable tumor with some necrotic and/or fibrotic tissue (category b), predominance of fibrosis and recrosis (category c), and no evidence of tumor, i.e., pathologically proven complete response (PCR) (category d). All of the patients in categories a and b had died because of ovarian cancer at the end of the observation period. In category c, 17/25 patients eventually achieved a PCR as established at a third-look procedure. The median survival of 56 months in this group was lower than that of the patients in category d (64 months), although this difference was without statistical significance. These observations underscore the importance of the microscopical features of the second-look specimen for the treatment of advanced ovarian cancer.