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Ovarian cancer represents the fifth most frequent cause of death as a result of malignant processes after cancers of the breast, large intestine, lung and stomach. Owing to the localisation of ovarian cancer, approximately 75% of cases are diagnosed at the III and IV stages of advancement according to FIGO. Because of the advanced stage of the disease surgery has to be followed by chemotherapy in most cases of ovarian cancer and therefore resistance to cytostatic drugs represents a major clinical problem. The potential to predict the response to therapy with the use of cytostatic drugs would enable the most effective drugs to be applied in individual cases, thus improving the efficiency of the treatment and restricting the development of resistance to cytostatic drugs. In the present paper the progress made so far in the prediction of the clinical course of ovarian cancer is reviewed. The significance of the expression of the ATP-binding cassette (ABC) transporters is described, including P-glycoprotein and MRP2, the principal representatives of the protein group. The importance of disturbed control of apoptosis and the overexpression of HER-2 and topoisomerase 1A are also discussed. Two sections are devoted to the most recent studies in the biology of ovarian cancer, pangenomic studies on gene expression using DNA microarrays and aberrations of DNA methylation.

In case of breast cancer the grade of differentiation and expression of oestrogen and progesterone receptors falls within the first category of prognostic factors according to the College of American Pathologists. HER-2, p53 and Ki67 belong to the second category and their significance still awaits confirmation. The aim of the present study was to examine the relationship between the intensity of expression of oestrogen receptors (ER), progesterone receptors (PgR), HER-2, p53 and Ki67 in cells of ductal breast cancer of G1, G2 or G3 differentiation grade. In paraffin sections of 60 ductal breast cancers (20 cases in G1, 20 in G2 and 20 in G3), immunocytochemical reactions were performed to detect the expression of ER, PgR, HER-2, p53 and Ki67. Following a semi-quantitative appraisal of the preparations under examination, appropriate statistical tests were used to document significant relationships. We noted significant positive correlations between ER and PgR (the entire group studied, G1-3, and the G1 group), HER-2 and p53 (G2) and between p53 and Ki67 expression (G2). Significant negative correlations were found between ER and p53 (G1-3), PgR and p53 (G1-3, G1, G3) and between PgR and Ki67 (G1-3, G2). The studies performed demonstrated distinct relationships between the expression intensity of various proteins in tumour cells in relation to the grade of differentiation of the tumour. We also showed that a parallel determination of ER, PgR and p53 expression may carry high predictive value as to response to tamoxifen treatment.

Overexpression of SGTP and/or MT may contribute to various carcinogenic processes and to resistance to anticancer treatment. The importance of these proteins, although clearly established in solid tumours, has not been fully understood in haematopoietic neoplasm. The aim of this study was to determine the expression of MT and SGTP in the bone marrow of patients with MPD. Twenty paraffin-embedded bone marrow core biopsy specimens from newly diagnosed patients with MPD were evaluated -- osteomyelofibrosis (OMF), n = 9 and chronic myelocytic leukaemia (CML), n = 11. We demonstrate increased SGTP and MT expression in the bone marrow of MPD patients. In our study levels of MT in OMF patients were higher than in CML. This suggests that MT expression may correlate with bone marrow fibrosis. These data, although based on a relatively small number of patients, raise the possibility that SGTP and MT may play a role in the pathogenesis of MPD. The clinical significance of this phenomenon needs further investigation.

The use of exogenous surfactants has been introduced into the therapy of patients of different ages. Much better results have been obtained in the treatment of respiratory distress syndrome with surfactants enriched with surfactant proteins. In the following study we used protein-containing surfactants (survanta and curosurf). The aim of the following study was to determine the localisation of artificial surfactants in the lung tissue. Using the Immunogold Technique, biotinylated surfactant proteins were traced in the air-blood barriers. In all lungs the exogenous surfactant was present only in some alveoli. In these parts small areas of atelectasis as well as oedema and transudate accumulation were seen. These changes were less severe after biotinylated curosurf treatment. In electron microscope studies we found surfactant elements in the air-blood barrier and other structures of the alveolar septa. Immunogold studies confirm the presence of biotynylated surfactant in the elements of the air-blood barrier.

Metallothioneins (MT) represent low molecular weight proteins that are supposed to fulfil several functions. They participate in the cell cycle, protect cells from oxidative stress, control levels of heavy metals and participate in multidrug resistance processes, particularly in cases of alkylating drugs. The present study aimed at evaluation of proliferation intensity (Ki67, PCNA) in ovarian cancers treated using cisplatin and paclitaxel, as related to expression of MT. The experiments were performed on samples originating from 10 patients operated on due to ovarian cancer. The material originated from the first operations or second-look operations. All the patients were treated with cisplatin and paclitaxel. Immunocytochemical reactions using antibodies to MT, Ki67 and PCNA were performed in paraffin sections originating from the cases studied. Statistical analysis was performed using Statistica software. The studies demonstrated no relation between expression of MT on the one hand and intensity of proliferation before or after chemotherapy on the other hand (gamma correlation, p > 0.05). The results indicate that expression of MT is not related to resistance to treatment using cisplatin and paclitaxel.

Silencing of genes using siRNA represents a generally used technique aimed at inhibiting expression of proteins in cells. Results have frequently not met expectations and this has posed problems in association with this technique. The phenomenon might reflect an incorrect sequence of RNAi, poor penetration of the cells by the nucleotides or insufficient knowledge of the protein in question. The present study is aimed at evaluating the effectiveness of the transfection of selected cell lines using various liposomes. The studies were performed using 9 cell lines: EPG 257/85 RNOV, EPG 257/85 RDB, W 181/A17, A 2780P, A 2780 RCIS, MEWO CIS, 181 RDB, 181 P and MCF-7/MX. The lines were transfected with fluorescently labelled oligonucleotides. Two parallel experiments were performed. In one oligofectamin and in the other DMRI were used as oligonucleotide carriers. The studies demonstrated that in every case nucleotides penetrated more than 90% of the cells. In 4 cell lines the signal was stronger when oligofectamin was used, in 4 cell lines when DMRI was employed and in one case the signal strength was comparable using any carrier. The studies showed that various liposomes demonstrated distinct transfection efficiency, depending on the cell line used, and that application of fluorescently labelled nucleotides may be helpful in the optimisation of transfection conditions.