van der Ate Zee

Sentinel Lymph Node Procedure Is Highly Accurate in Squamous Cell Carcinoma of the Vulva

PURPOSE To determine the diagnostic accuracy of the sentinel lymph node procedure in patients with squamous cell carcinoma of the vulva and to investigate whether step sectioning and immunohistochemistry of sentinel lymph nodes increase the sensitivity for detection of metastases. PATIENTS AND METHODS Between July 1996 and July 1999, 59 patients with primary vulvar cancer were entered onto a two-center prospective study. All patients underwent sentinel lymph node procedure with the combined technique (preoperative lymphoscintigraphy with technetium-99m-labeled nanocolloid and intraoperative blue dye). Radical excision of the primary tumor with uni- or bilateral inguinofemoral lymphadenectomy was performed subsequently. Sentinel lymph nodes and lymphadenectomy specimens were sent for histopathologic examination separately. Sentinel lymph nodes, negative at the time of routine pathologic examination, were re-examined with step sectioning and immunohistochemistry. RESULTS In 59 patients, 107 inguinofemoral lymphadenectomies were performed (11 unilateral and 48 bilateral). All sentinel lymph nodes, as observed on preoperative lymphoscintigram, were identified successfully intraoperatively. Routine histopathologic examination showed lymph node metastases in 27 groins, all of which were detected by the sentinel lymph node procedure. The negative predictive value for a negative sentinel lymph node was 100% (97.5% confidence interval [CI], 95% to 100%). Step sectioning and immunohistochemistry showed four additional metastases in 102 sentinel lymph nodes (4%; 95% CI, 1% to 9%) that were negative at the time of routine histopathologic examination. CONCLUSION Sentinel lymph node procedure with the combined technique is highly accurate in predicting the inguinofemoral lymph node status in patients with early-stage vulvar cancer. Future trials should focus on the safe clinical implementation of the sentinel lymph node procedure in these patients. Step sectioning and immunohistochemistry slightly increase the sensitivity of detecting metastases in sentinel lymph nodes and should be included in these trials.

Anticancer Drugs Aimed at E6 and E7 Activity in HPV-Positive Cervical Cancer

Standard treatment of locally advanced cervical cancer currently consists of concurrent chemoradiation, leading to a 5-year disease-free survival of 66-79%, indicating that there is still ample room for improvement. Characteristic of cervical cancer is the presence of high risk (HR) human papillomavirus (HPV) DNA in more than 99% of these tumors. When the HR HPV genome integrates into the host genome, oncogenic E6 and E7 proteins become constitutively expressed. These oncogenes are also active earlier in the infection cycle and hence are available as therapeutic targets at the preneoplastic stages as well. E7 plays an important role in the early stage of carcinogenesis by stimulating proliferation. HR HPV E6-induced proteasomal degradation of p53 hampers p53 functionality in cell cycle arrest and apoptosis. As p53 plays a key role in the intrinsic apoptotic pathway, current chemoradiation cannot optimally activate this pathway. In this review, we focus on targeted anticancer drugs to eliminate the consequences of HR HPV E6 and E7 activity. Strategies for direct and indirect targeting of HR HPV E6 and E7, including RNA interference, small molecules, proteasome inhibitors, and histone deacetylase inhibitors, are described. In addition, the extrinsic apoptotic pathway as possible alternative therapeutic target for apoptosis induction is reviewed. The rational for implementing recombinant human TRAIL and death receptor agonists and the latest developments on combining these drugs with standard treatment in preclinical settings as well as clinical trials are discussed.

Analysis of the entire HLA region in susceptibility for cervical cancer: a comprehensive study

Background: Infection with human papillomavirus (HPV) is the main cause of cervical cancer and its precursor lesion, cervical intraepithelial neoplasia (CIN). Variability in host immunogenetic background is important in determining the overall cellular immune response to HPV infections. Objective: To determine whether the HLA-DQ or HLA-DR genes, or others in their vicinity, are associated with cervical cancer. Methods: Markers covering the entire HLA region were genotyped in a large sample of CIN and cervical cancer patients and in controls (311 CIN, 695 cervical cancer, 115 family controls, and 586 unrelated controls). Results: Two markers were associated with susceptibility to cervical neoplasia, G511525 and MICA. G511525, close to the region containing the HLA-DQ and HLA-DR genes, was most strongly associated, showing a decrease in frequency of allele 221 from 6.7% to 3.3% in patients with squamous cell cancer (SCC). An association was found for MICA (allele 184) with SCC (odds ratio (OR) = 1.31 (95% confidence interval, 1.13 to 1.53); homozygotes, OR = 1.48 (1.06 to 2.06)). No associations were observed with adenocarcinoma or CIN. Conclusions: There is an association of the region containing the HLA-DQ and HLA-DR genes with the risk of developing squamous cell carcinoma. An increased risk was observed for carriers of allele 184 at the MICA locus, in particular for homozygotes, suggesting a recessive effect.

Drug-induced caspase 8 upregulation sensitises cisplatin-resistant ovarian carcinoma cells to rhTRAIL-induced apoptosis

Background:Drug resistance is a major problem in ovarian cancer. Triggering apoptosis using death ligands such as tumour necrosis factor-related apoptosis inducing ligand (TRAIL) might overcome chemoresistance.Methods:We investigated whether acquired cisplatin resistance affects sensitivity to recombinant human (rh) TRAIL alone or in combination with cisplatin in an ovarian cancer cell line model consisting of A2780 and its cisplatin-resistant subline CP70.Results:Combining cisplatin and rhTRAIL strongly enhanced apoptosis in both cell lines. CP70 expressed less caspase 8 protein, whereas mRNA levels were similar compared with A2780. Pre-exposure of particularly CP70 to cisplatin resulted in strongly elevated caspase 8 protein and mRNA levels. Caspase 8 mRNA turnover and protein stability in the presence or absence of cisplatin did not differ between both cell lines. Cisplatin-induced caspase 8 protein levels were essential for the rhTRAIL-sensitising effect as demonstrated using caspase 8 small-interfering RNA (siRNA) and caspase-8 overexpressing constructs. Cellular FLICE-inhibitory protein (c-FLIP) and p53 siRNA experiments showed that neither an altered caspase 8/c-FLIP ratio nor a p53-dependent increase in DR5 membrane expression following cisplatin were involved in rhTRAIL sensitisation.Conclusion:Cisplatin enhances rhTRAIL-induced apoptosis in cisplatin-resistant ovarian cancer cells, and induction of caspase 8 protein expression is the key factor of rhTRAIL sensitisation.

Prognostic factors in ovarian cancer : current evidence and future prospects

Abstract In ovarian cancer, translational research on the prognostic impact of molecular biological factors has until now not led to clinical implementation of any of these factors. This is partly due to the often conflicting results of different prognostic factor studies on the same molecular biological factor. We have performed meta-analyses on studies in ovarian cancer on four putative prognostic molecular biological factors, epidermal growth factor-receptor (EGFR), HER-2/neu, glutathione-S-transferase (GST)-pi and p53. Odds ratios were estimated for the increase in death at 1 and 5 years for patients with ovarian cancer, harbouring aberrant EGFR, HER-2/neu, GST-pi and p53, respectively. Patients with aberrant Her2/neu or p53 in their tumours had significantly worse odds of surviving 1 and 5 years, respectively. Patients with aberrant EGFR in their tumours only had a significantly greater risk of mortality at 5 years, while there seemed to be a trend for a decreased probability of 5-year survival for patients with aberrant GST-pi in their tumours. Despite inevitable flaws (such as small individual study sizes, publication bias, etc.) our meta-analysis confirms that therapeutic drugs targeted at EGFR, HER-2/neu, GSTpi and p53 may have therapeutic potential. Since ovarian cancer is a relatively rare disease, international collaboration to increase the number of patients to be analysed is critical for progress in translational research on the prognostic impact of molecular biological factors and on innovative treatment in ovarian cancer. In addition it is important to reach a consensus about guidelines for the design, conduct and analysis of translational studies in ovarian cancer.

Potential Target Antigens for a Universal Vaccine in Epithelial Ovarian Cancer

The prognosis of epithelial ovarian cancer (EOC), the primary cause of death from gynaecological malignancies, has only modestly improved over the last decades. Immunotherapeutic treatment using a cocktail of antigens has been proposed as a “universal” vaccine strategy. We determined the expression of tumor antigens in the context of MHC class I expression in 270 primary tumor samples using tissue microarray. Expression of tumor antigens p53, SP17, survivin, WT1, and NY-ESO-1 was observed in 120 (48.0%), 173 (68.9%), 208 (90.0%), 129 (56.3%), and 27 (11.0%) of 270 tumor specimens, respectively. In 93.2% of EOC, at least one of the investigated tumor antigens was (over)expressed. Expression of MHC class I was observed in 78.1% of EOC. In 3 out 4 primary tumors, (over)expression of a tumor antigen combined with MHC class I was observed. These results indicate that a multiepitope vaccine, comprising these antigens, could serve as a universal therapeutic vaccine for the vast majority of ovarian cancer patients.

DNA topoisomerase IIα and -β expression in human ovarian cancer

SummaryTo study DNA topoisomerase IIα (Topo-IIα) and -β expression and regulation in human ovarian cancer, 15 ovarian tumour samples were investigated. To compare different levels of expression, the samples were screened for topo IIα and -β mRNA with Northern blotting and a quantitative reverse transcriptase polymerase chain reaction (RT-PCR) assay for Topo-IIα mRNA. Additionally, protein levels were determined with Western blotting and topoisomerase II activity levels with the decatenation assay. The results obtained were compared with each other and with the tumour volume index of the samples. In tumours with a tumour volume index ≥ 50%, the mRNA levels (as determined by Northern blotting) and protein levels for each isozyme were in accordance. Additionally, correlations were found between Topo-IIα RT-PCR data and Topo-IIα Northern blot results, and between Topo-IIα RT-PCR data and Topo-IIα protein levels. Interestingly, Topo-IIβ protein levels correlated better with Topo-II activity than Topo-IIα protein levels. In eight ovarian cystadenoma samples, no Topo-IIα protein could be found. In only three out of eight of these cystadenomas, Topo-IIβ protein could be detected. These findings suggest that Topo-IIα and Topo-IIβ protein levels are up-regulated in ovarian cancer and may indicate that Topo-IIβ is an interesting target for chemotherapy in ovarian tumours.

Antagonism of HSV-tk transfection and ganciclovir treatment on chemotherapeutic drug sensitivity

Abstract Our study focused on the influence of herpes simplex virus thymidine kinase (HSV-tk) expression and ganciclovir (GCV) treatment on the sensitivity of C6 glioma cells to frequently used chemotherapeutic drugs, i.e. adriamycin (ADR), cisplatin (CDDP), 5-fluorouracil (5-FU), and methotrexate (MTX). Transfection with HSV-tk revealed an increased sensitivity to GCV and CDDP and a decreased sensitivity to ADR and MTX. No significant differences were found in sensitivity to 5-FU. Combined treatment in a HSV-tk negative cell line revealed an additive effect when GCV was combined with ADR, whereas an antagonistic effect was found when GCV was combined with CDDP, 5-FU, or MTX. Comparable results were obtained in an HSV-tk positive cell line, apart from CDDP, which showed an additive effect. In conclusion, both HSV-tk transfection and subsequent GCV treatment can influence the sensitivity of tumor cells to various chemotherapeutic drugs in an antagonistic manner. Therefore, combining HSV-tk/GCV gene therapy with chemotherapy might not always be beneficial.

A Distributed Object Model for CSCW in the Construction Industry

Information about products for the construction industry is increasingly often provided to designers in digital ways that enable them to apply the information directly in the design process. Digital product catalogues are provided using various media and formats and several initiatives are taken by the industry and by CAD developers to integrate this kind of information into CAD systems. Generally, current practice is to distribute the information to designers, for example, by using CD-ROMs or a website where the information can be downloaded. In our research we recognise that distributing information in this manner detaches it from the business processes in the construction supply chain, which is a major disadvantage. The project presented in this paper concerns the implementation in the Dutch construction industry of a methodology for sharing product information through a distributed object model. The methodology, which is called Concept Modelling, forms a generic basis for the support of collaborative design, but is applied in this project to the integration of information from the supply chain in the design process. Through the distributed object model, design information and product information can be integrated while the actual data objects remain at their source. This enables the supply chain to provide information of a high semantic level to designers while keeping the control over the information and maintaining the relationship of the information with their business processes. The advantages of this approach in which information is shared, rather than exchanged, are numerous. Redundancy of information is minimised, consistency is improved, and updated information is available immediately. Moreover, design and construction processes can benefit significantly from the dynamic aspects of accessing information that is tied to business processes in the supply chain. For example, product selection during design can be based on latest information on product details, prices, production methods, and variants of products. This information can be provided to designers automatically and on demand.