[en] Susceptibility to cytostatic activity of non-activated macrophages (Mph) of Syrian hamster embryo fibroblasts (HEF) transformed in vitro by BAV-3, SV40, RSV-SR, or spontaneously and of their in vivo selected variants was studied in dynamics (5 days of co-incubation). With the use of ³H-TdR incorporation test it was demonstrated that HEF transformed by BAV-3 appeared to be able to overcome the cytostasis at co-incubation with with Mph, in contrast to deeply suppressed spontaneously transformed cells of STHE strain. HEF transformed by SV40, or RSV-SR appeared to be resistant to growth-inhibiting activity o Mph during almost all the 5-day period. The in vivo selected malignant variants of STHE cells were able to recover from cytostasis after 4-5 days of the co-incubation with non-activated Mph, in contrast to low-malignant variant and to parental cell strain. (author)

[en] The concentrations of three steroid hormones (estrogen, progesterone and 1,25-dihydroxycholecalciferol) receptors (ER, PgR, DR) in tissue cytosol were analyzed in a group of 17 breast phylloid tumors. Comparison with breast carcinoma tissue samples (n=37) did not reveal significant differences in average values of ER, PgR, and DR. Comparison with another control set of 30 samples of dysplastic tissue of the mammary gland showed significant differences only in PgR values. Only 18% of phylloid tumor samples contained levels above cut-of-line of all three receptors (ER, PgR, DR - 5, 10, 10 resp. fmol/mg protein. The most frequent combination was ER+PgR+DR- (41%). As far as we know, DR in phylloid breast tumors have never been examined before. In approximately 60% of our samples we found the expression of DR, in 36% the estimated values were above 10 fmol/mg protein. Cells of the tissue not expressing DR seems to belong to a special phenotype. We found no ER+PgR- or ER-PgR- combinations in them. The group which expressed DR is characterized by a higher dispersion of PgR values. (authors)

[en] Multiple fractions of gamma rays (0.5 Gy daily, 30 fractions) had previously been found to change the sensitivity of human cervical carcinoma HeLa cells to anticancer drugs. Preirradiated cells became resistant to cisplatin, methotrexate and vincristine but retained the same sensitivity to gamma rays and ultraviolet light. Some mechanisms involved in the resistance of preirradiated cells to cisplatin and vincristine were determined, i.e. the increased levels of metallothioneins and increased expression of plasma membrane P glycoprotein. As recent reports indicated that the resistance to cisplatin and ionizing radiation may involve the expression of oncogenes, the problem was studied whether multiple fractions of gamma rays can change the expression of c-myc and c-Ki-ras oncogenes in HeLa cells and whether there is a correlation between the expression of these oncogenes and the sensitivity of preirradiated cells to cisplatin and gamma rays. The expression of c-myc and c-Ki-ras oncogenes was examined using the DNA dot blot, the RNA dot blot and Northern blot analysis. The results show that preirradiation induced neither amplification nor elevated expression of c-myc and c-Ki-ras oncogenes. Furthermore, there is no correlation between the expression of c-myc and c-Ki-ras oncogenes and the acquired resistance to cisplatin. (author) 3 figs., 32 refs

[en] The effect was investigated of muramyl tripeptide (MTP-PE) encapsulated in liposomes (multilamellar vesicles, MLV) on hemopoiesis and hemopoietic recovery after sublethal single irradiation with a dose of 6 Gy. MTP-PE/MLV during 24 h after administration stimulated the monocyte/macrophage system and accelerated the recovery from radiation-induced damage of hemopoiesis. The reparative processes were accompanied by hyperplasia of granulocytes in the bone marrow on days 6-8 after irradiation, acceleration of erythropoiesis in the spleen and recovery of granulocyte count in the peripheral blood. The repair of thymic and splenic lymphoid tissues as well as recovery of the number of mononuclear cells in peripheral blood was not influenced by MTP-PE/MLV application. (author) 8 figs., 40 refs

[en] Fraction size in radiotherapy of malignant melanoma remains a point of controversy. Among 139 patients treated at the University of Illinois Hospital in 1979-1988, 36 were considered potentially curable (not counting ocular melanomas); 20 were treated by the Princess Margaret Hospital (PMH) hypofractionated schedule using 800 cGy per fraction and achieved a permanency of local control lasting > 6 months since the beginning of radiotherapy in 10/22 (45.5%) courses. Comparable results were obtained in 11 patients treated by standard fractionation to at least threshold curative levels. A modification of PMH regimen in 5 patients (but with 13 courses) by decreasing fraction size to 400 cGy while keeping total dose and course duration unchanged, resulted in a 100% loss of focal control within 6 months. Patients considered incurable and irradiated by PMH schedule responded in 83% of courses compared to 51.4% response rate in patients irradiated with other schedules (except) modified PMH regimen). Other aspects of melanoma management are analyzed. (author) 12 tabs., 3 figs., 32 refs

[en] The ROC (receiver operating characteristic) analysis of optimization of radiation treatment of cancer of oral cavity was carried out. Material of 210 patients with squamous cell carcinoma of the oral cavity was included into the study. Based on dose-response curves for tumor and late mucosal reactions, iso-utility curves and optimal k values were estimated. Optimal k values decreased from 0.792 to 0.584 with extension of overall treatment time from 35 to 49 days. This may suggest that the planning of additional dose to compensate tumor clonogens repopulation during prolonged treatment does not improve the therapeutic gain in radiotherapy for cancer of the oral cavity. The ROC is a useful model to estimate the optimal radiation treatment for a given tumor because it is independent of any arbitrary consensus or theoretical assumption. (author) 1 tab., 3 figs., 5 refs

[en] Murine sarcoma cell line (L-1) treated with promoting phorbol ester (TPA) showed decreased content and activity of protein kinase C (PKC) as measured by Western blotting and histone phosphorylation methods. The PKC depleted line (L-1 R) produced bigger, tumors after s.c. transplantation into syngeneic mice and more spontaneous and artificial metastases developing after i.v. injection of tumor cells. (author)

[en] Data on 946 skin cancers treated by radiation were used to estimate the importance of repopulation. Six different treatment regimes were used, from a single dose to 74 Gy given in 47 fractions. High local control of the small skin cancers (L 1 cm) was independent of dose fractionation. For large tumors, only 74 Gy in 47 fractions was the optimal treatment. Time factor analysis showed a steep increase in the NTD50 values between day 28 and 65 of treatment. This implies that tumor clonogen repopulation starts around 4 weeks of treatment. The present results show a three-component dose-response curve instead of the two-component curves which were found for head and neck and bladder cancer. (author) 1 tab., 2 figs., 15 refs

[en] The parameters of nonspecific immunity - serum immunoglobulins and immune complexes - were evaluated in patients with carcinoma of the uterine cervix (stages IIB and IIIB) prior to, during and immediately after pelvic irradiation. In untreated patients, significantly elevated circulating IgA was found only in patients in stage IIIB; serum IgB and IgM in both groups did not differ from control values. The level of circulating immune complexes in both groups was higher than in controls. Radiotherapy did not significantly affect any of the parameters examined; only the percentage of patients with elevated concentrations of IgA and IgC decreased during the treatment. These results showed that fractionated pelvic irradiation did not affect B cell function, these cells being more radioresistant than other lymphocyte subpopulations. (author) 4 figs., 16 refs

[en] The purpose of this paper is to evaluate the incidence and kinetics of distant metastases in operable breast cancer and to relate these estimates to various tumor and patient characteristics. The records of 309 consecutive patients with operable breast cancer in stage T_1-4N_0-1M₀ were reviewed, and the incidence of distant metastases (DM) and death due to DM were evaluated. 195 patients had positive axillary nodes with following distribution of the number of nodes: 45% had 1-2 node, 16% had 3-4 nodes, 14% and 25% had 5-7 and more nodes, respectively. All patients were treated with radical mastectomy with axillary nodes dissection (the only treatment in 39% of cases). In 198 cases radical mastectomy was combined with radiotherapy and/or chemotherapy given pre- or postoperatively. Hormonal treatment was given in 27% of cases. Minimum follow-up was 10 years. Distant metastases were found in 150 cases (49%) and in 78 cases (25%) they develop early, during the first 18 months follow-up. Average rate of DM in N₀ cases was 25%. Number of involved nodes and extra-capsular invasion were found significant and independent prognostic factors. High risk (%)%) of DM and death due to DM correlate with age <40 y, pre-menopausal status, tumor stage =>T₃, more than 2 axillary nodes and or extra-capsular invasion. The linearity of the curves for freedom from DM and for freedom from death due to the DM suggest uniform distribution of progression rates with a median value for halving time for freedom from early DM of about 8 months, and of about 40 months for freedom from the DM occurring later than 18 months, being for whole group and average of 20 months. High incidence of DM is a significant cause of poor long-term survival. Early appearance (<18 month follow-up) of about half of the DM suggests that they are already present as subclinical micrometastases at the time of initial loco-regional treatment. The time of appearance of distant metastases is consistent with a wide range of metastatic cell burdens among patients. Systemic therapy, at least for selected group of patients, might decrease the incidence of DM and improve long-term results. (authors)