The behavior of cells during the evaluation of gap junctional intercellular communication by metabolic cooperation assay.

The behavior of cells during the assessment of gap junctional intercellular communication (GJIC) by metabolic cooperation assay was studied, either under standard conditions, or with the simultaneous addition of an inhibitor of GJIC-ethylene glycol, and eventually plus dibutyryl cyclic adenosine monophosphate. Generally, the behavior of cells in the course of the assay did not depend significantly on the combination of drugs used. Cell locomotion during the assay was minimal, and consequently the results depended, almost solely on the probability of mutual contact between donor and recipient cells during the seeding. The first significant decrease in recovery of recipient cells, that is a detectable GJIC, was observed 30 min after the assay had started. Final results of the assay depended on the first 12 h of the experiment, in which the maximum decrease in the recovery of recipient cells, that is the maximum GJIC, was reached. The longer duration of the assay did not affect the results significantly.

Dynamics and phases of changes in the primary focus of Morris hepatoma under local application of cytokine hrecTNF-alpha.

Biological activity of cytokine hreeTNF-alpha was tested on a transplantable Morris hepatoma 5123 in Buffalo rats. Local effects of hrecTNF-alpha activity were evaluated basing on morphological examinations. The cytokine effects on tumor biometric parameters and body mass of experimental animals were analyzed. It has been found that hrecTNF-alpha considerably decreases body mass and reduces studied parameters of the tumor, the changes being statistically significant. Three consecutive phases of the neoplasm regression have been distinguished. Phase I revealed prevailing hemorrhagic necrosis of the central and intermediate zones, with numerous thrombi in the vascular lumen and fibrinoid necrosis of vascular walls. Phase II presented a number of cellular infiltrations, clearance of necrotic foci and initial angiogenesis and fibroplasia. Phase III showed intensified angiogenesis and proliferation of the connective tissue in the peripheral and intermediate zones.

Autopsy findings in small cell lung cancer.

The objective of this study was to assess the pattern of autopsy findings in 174 small cell lung cancer patients treated between 1971 and 1991 at seven Polish medical centres. Eighty nine autopsied patients were previously treated with different chemotherapy regimens including 32 patients who also received chest irradiation, 74 received only supportive care and for 11 patients the data on treatment were not available. The age range at diagnosis was 28-81 years (median 57); there were 39 females (22%) and 135 males (78%). Seventy two patients had limited disease at the time of diagnosis, 86-extensive disease and in 16 the disease extent was not determined. The primary tumor and/or metastases in regional lymph nodes were present in 157 autopsies (90%). There was a significant difference in the rate of locoregional disease found at autopsy in patients given chemotherapy and in those who received only supportive care (85% and 100%, respectively; p = 0.01). Chest radiation therapy given in limited disease as an adjunct to chemotherapy did not decrease the rate of persistent locoregional disease (primary tumor in the chest was found in 92% of irradiated and in 96% of nonirradiated patients). Locoregional tumor deposit only was found in 28 (16%). Distant metastases were distributed in 143 patients (82%) and were found in 25 different locations, most frequently in liver (49%), suprarenal glands (25%), peripheral lymph nodes (21%), kidneys (18%), brain (17%) and pancreas (12%). In 3 patients no tumor foci were found. The number of organs involved varied between 0 and 10 (median 3). The number of involved organs was not dependent on the disease extent at the time of diagnosis and on the type of treatment.

Cancer in hyperthyroidism.

The aim of the study was to determine the incidence of thyroid cancer in toxic goitre. Based on the material from 14,500 goitre surgeries, including 3,466 patients with toxic goitre, incidence of thyroid cancer, in relation to age and sex of the patients were determined. In 14,500 goitre surgeries, 12,887 women and 1,613 men (F:M 7.99:1), 639 (4.4%) cases of thyroid cancer were found. Among 3,466 patients with toxic goitre, thyroid cancer was found in 21 cases (0.6%)-20 females and 1 male, including 18 nodular toxic goitre and 3 Graves disease cases. The difference between the incidence of thyroid cancer in nontoxic and toxic goitre is statistically significant.

Pilot study of enhancement of cisplatin activity by high dose cytarabine in advanced gastric and colorectal (G3/G4) cancer.

The response rate of advanced gastric cancer to cisplatin monotherapy averages 20% and in colorectal cancer no activity of cisplatin monotherapy has been detected in initial studies. Cytarabine is ineffective in gastric cancer and displays borderline activity in colorectal cancer. In vitro studies on cell lines from human digestive cancers have demonstrated a dose and timing dependent enhancing effect of cytarabine on cisplatin antitumor activity. The aim of the present study was to investigate whether this enhancing activity can also be demonstrated in vivo. We have treated 37 patients with advanced gastrointestinal cancer (21 gastric and 16 colorectal), poorly differentiated G3-G4. The treatment included-Day 1: cytarabine 500 mg/m2 0 h and 12 h, cisplatin 15 mg/m2 6 h and 18 h. Day 2-4:cisplatin 30 mg/m2. Cycles were repeated every 4 weeks. Thirty four patients were evaluable for objective response. The overall response rate was 16.7% (CR 2/18, PR 1/18, SD 5/18, PD 10/18) for patients with gastric cancer and 25% (CR 1/16, PR 3/16, SD 7/16, PD 5/16) for patients with colorectal cancer. Grade 4 anemia (WHO criteria) occurred in 1/37 and thrombocytopenia in 1/37 patients. These patients had previous adjuvant chemotherapy. Vomiting grade 3 occurred in 4/37 and hepatotoxicity grade 3 in 1/37 patients. There were no toxic deaths. Our study did not demonstrate any enhancement of cisplatin activity by high dose cytarabine in advanced gastric cancer. There appears to be an enhancing activity on colorectal cancer although true synergism can not be ruled out since cytarabine has a borderline activity in this type of human cancer.

Pretreatment values of serum CA 15-3 antigen related to prognostic factors in breast cancer patients.

In the present study results of serum CA 15-3 immunoassay obtained at diagnosis in 231 breast cancer women (average age: 54.6, range: 27-87 years) were correlated with prognostic factors of the disease; the cut-off level was established at 30.0 U/ ml. As a result, elevated mean values of serum CA 15-3 as well as positivity rates of the test were significantly associated with more advanced stage of breast cancer, presence of distant metastases, involvement of four and more axillary lymph nodes, high BLOOM and RICHARDSON grade [3], low contents of estrogen (ER) and progesterone (PgR) receptors. Although serum CA 15-3 concentrations should be paralleled the increasing tumor size, the difference being significant only for the proportion of positive results. Our findings suggest that pretreatment levels of CA 15-3 antigen represent the breast cancer extent and reflect the cell differentiation and aggressiveness of the tumor. We conclude that pretreatment concentrations of CA 15-3 antigen may be useful as a prognostic factor in breast cancer patients.

Sequential pulmonary effects of radiotherapy detected by Tc-99m DTPA radioaerosol inhalation lung scintigraphy.

Lung damage after radiation therapy in 39 female patients diagnosed with right breast cancer was measured by Tc-99m DTPA radioaerosol inhalation lung scintigraphy (DTPA). The clearance rate of Tc-99m DTPA in the lungs was presented as the clearance rate (k; %/min) of the time-activity curve of the dynamic lung images. All patients underwent simple mastectomy, and postoperative radiation of approximately 50 Gy. We divided the patients into three groups according to the interval of time between the date of irradiation and the lung scintigraphy: group 1 included 12 patients who were examined within three months after irradiation, group 2 included 16 patients who were examined 3 to 9 months after irradiation, and group 3 included 11 patients who were examined more than 9 months after irradiation. In addition, 10 age matched normal women were included as the control. The clearance of the right lung was 0.73 +/- 0.13 for normal controls, 0.94 +/- 0.24 for group 1, 1.11 +/- 0.39 for group 2, and 0.69 +/- 0.21 for group 3. In this small series of patients with breast cancer, the results suggest that lung damage may occur within the first three months after irradiation. After three months, lung damage becomes more significant and the clearance of Tc-99m DTPA in the lungs becomes faster. However, the clearance rate declines markedly after 9 months, which is assumed to result from the recovery of lung tissue from acute irradiation damage or from pulmonary fibrotic change after radiation therapy, or from a combination of both.

Bloodstream infections due to anaerobic bacteria in cancer patients: epidemiology, etiology, risk factors, clinical presentation and outcome of anaerobic bacteremia.

Thirty one bacteremic episodes (BE) in 31 patients due to anaerobic bacteremia (AB) in 979 BE among 9986 admissions at a 360 beds National Cancer Institute within last 6 years were analyzed for time distribution, risk factors, clinical presentation and outcome. Overall incidence of AB was 3.6%, but the proportion to other groups of microorganisms is decreasing. 73% were Bacteroides fragilis, 10.8% Peptostreptococci and Propionibacteria and 5.4% Clostridia. The most common risk factor for AB was prior surgery, solid tumor as underlying disease, prophylaxis with quinolones and previous therapy with third generation cephalosporines. 48.4% of AB were polymicrobial. Infected wound was the most common source of infection in 38.7% of our cancer patients. Six patients (19.4%) presented septic shock, and 45.2% died, but only in 22.6% death was related to bacteremia. Comparing the groups of AB due to B. fragilis (BF) to non-Bacteroides spp. (NB)AB, infection-associated mortality was higher in BFAB in comparison to NBAB. Other risk factors such as hematologic malignancies, previous prophylaxis with quinolones, prior surgery and prior therapy with broad spectrum antimicrobials, were more frequently associated with BFAB.

Variant forms of Philadelphia translocation in two patients with chronic myeloid leukemia.

During a 4-year period (December 1990-December 1994), among other diagnoses one hundred cases of chronic myeloid leukemia (CML) were analyzed in our department. We focused our attention on two cases with a variant form of Philadelphia translocation. Cytogenetic and molecular genetic studies were performed to resolve the status of BCR and ABL in the bone marrow or peripheral blood cells of the two CML patients with complex translocations involving chromosomes 3, 9, 22 and 9, 12, 22 respectively. In the first case the presence of Ph chromosome was detected cytogenetically, BCR-ABL translocation was detected by Southern hybridization. In the second case, only the PCR method showed BCR-ABL rearrangement. The second case, with a random variant form of Ph translocation, could be detected using different methods of clinical molecular genetics.

Clinical and immunologic effects of T-activin therapy in early stage melanoma patients.

We investigated the clinical and immunological effects of T-activin therapy in early stage melanoma patients. Several immune parameters (the number of T cells-E-RFC and CD3+, their subsets-CD4+ and CD8+, the number of CD38+ and CD16+ cells, and mitogen-induced lymphoproliferative response-LPR) were analyzed in relation to the clinical course of the disease in patients treated by T-activin in addition to the surgery (n = 8), and in control patients treated by the surgery alone (n = 9). Immunological tests were performed before therapy and one month after the last (6th) cycle of T-activin, i.e. six months after surgery in controls. The patients were followed-up from February 1991 to August 1995. Clinical evaluation showed that disease-free interval for observed period was similar in both groups of patients (17.5 and 13 months), while the survival time was longer in T-activin-treated patients than in controls (40 vs. 24 months), although this difference was not significant. The phenotyping analysis of peripheral blood lymphocytes showed no changes of the pretreatment values of total T cells and their subpopulations regardless the clinical course of the disease in both groups of patients. The number of NK cells (CD16+) was significantly increased after T-activin therapy, but this increase was not associated with clinical benefit, since it was seen in patients with the progression of the disease. In control patients, the initial number of CD16+ cells did not change significantly, irrespective of the clinical course. The lymphoproliferative response increased significantly in 4 out of 5 T-activin-treated patients with the progression of the disease, while a slight increase of this lymphocyte function was seen in 3 disease-free patients. In patients treated by surgery alone, especially those with disease progression, the LPR was significantly decreased six months after tumor excision. These findings, although obtained in small number of patients, suggest an immunomodulatory action of T-activin therapy in early stage melanoma patients, which did not correlate with the clinical course of the disease. On the other hand, an almost doubled survival time in T-activin-treated patients in comparison to the controls, may indicate a possible effect of T-activin therapy on some other immune functions not evaluated in this study. Further investigations in a larger number of patients is needed for assessment of the true effectiveness of such therapy.

Recent trends in the incidence of lymphomas in Kuwait.

All cases of Hodgkin's disease (HD) and non-Hodgkin's lymphoma (NHL) reported to the Kuwait Cancer Registry between 1980-1989 were analyzed. Age specific and age standardized incidence rates were calculated for Kuwaiti and non-Kuwaiti males and females for the two periods of 1980-1984 and 1985-1989, and compared to detect short term changes. The study of 153 cases of HD and 325 cases of NHL in 1980-1984 and 213 cases of HD and 338 cases of NHL in 1985-1989 showed that HD incidence was stable in the two periods, the mixed cellularity subtype frequency and incidence declined, while the frequency and the incidence of nodular sclerosis increased significantly in the second period. These changes were most significant in the non-Kuwaiti males. The NHL incidence declined significantly in the 1985-1989 period. The incidence of low grade and intermediate grade NHL declined in the period of 1985-1989. The high grade NHL frequency increased, however, the annual incidence rate increase was not significant. The change in the HD subtypes may probably be related to the improvement in the socio-economic condition. The higher proportion of high grade lymphomas may be related to the population structure in Kuwait and is not related to the acquired immunodeficiency syndrome.

Selective modulation of non-protein sulfhydryl levels in Ehrlich ascites tumor bearing mice.

Thiazolidine derivatives (TD), prodrugs of L-cysteine (cys), synthesized by the condensation of cys with formaldehyde (thiazolidine-4-carboxylic acid-CF), acetaldehyde (2-methyl-thiazolidine-4-carboxylic acid-CA) and pyruvate (2-methylthiazolidine-2,4-dicarboxylic acid-CP), as well as amino acids thiocystine (T-cys) and cys, but not methionine (met) and S2O3(-2), successfully elevated non-protein sulfhydryl (NPSH) levels in livers of Ehrlich ascites tumor cells (EATC) bearing mice. At the same time, CA, promote a significant drop of NPSH concentration in EATC, whereas the other sulfur compounds (S-comp) have no effects. Thus TD and T-cys through their selective influence upon the level of NPSH in the liver and in cancer cells, seem to be the most interesting compounds for further studies on anticancer therapy.

Polarographic behavior of kojic acid and its derivatives, determination of potential carcinogenicity and correlation of these properties with their other attributes.

Polarographic properties of kojic acid [5-hydroxy-2-(hydroxymethyl)-4H-pyran-4-one] and 10 of their synthetic derivatives were investigated. It was shown that these compounds are reduced in anhydrous conditions, usually in one two-electron step or in two one-electron steps. The presence of some substituents may change the course of reduction process. The polarography of these compounds in the presence of alpha-lipoic acid showed the kojic acid analog-alpha-lipoic acid complex formation. The determined potential carcinogenic activity of these compounds expressed as a parameter tg alpha is not substantial.

In vivo effect of chemically induced fibrosarcoma on copper metabolism of liver in mice.

Copper and ceruloplasmin concentrations were determined in different subcellular fractions of liver of mice bearing benzo(a)pyrene induced fibrosarcoma. Though the copper content was elevated in the nuclear, mitochondrial and lysosomal fractions of tumor bearing mice, the microsomal and soluble supernatant fractions showed a downward trend in their copper concentration when compared to the controls. Similarly, ceruloplasmin concentration in the different subcellular fractions also showed variable results. This study was aimed to ascertain the distribution of copper. The incorporation of radioactive copper in different fractions was also monitored. The possible reasons for the variation in copper and ceruloplasmin concentrations observed during malignancy in the tumor bearing animals, has been discussed.

Two tumor-associated membrane antigens defined by monoclonal antibodies in a transplantable sarcoma induced by Rous sarcoma virus in rat.

Two hybridoma clones have been produced by hybridization of murine myeloma cell line PAI and splenocytes from BALB/c mice immunized with cells from a transplantable sarcoma induced in rat by SR-RSV. The antibody produced by hybridoma clone 2C2 was of subclass IgG3 and recognized a cell surface antigen of 52 kD. It only cross-reacted with cells from SR-RSV-induced sarcoma in hamster, but not with cells from the chicken RSV-induced sarcoma, nor with a number of methylcholanthrene sarcomas and various other tumors of viral or other etiology developed in rats, mouse, hamsters or chickens. The antibody produced by hybridoma clone 5G2 was of subclass IgG2A and recognized an antigen of 28 kD which was located under the plasma membrane, particularly in the cell protrusions and microvilli. Cross-reactions were found with all sarcoma cells tested, indicating that this antigen might represent a common sarcoma antigen of comparatively low molecular mass.

A possible role for the alpha 1-->3 galactosyl epitope and the natural anti-gal antibody in oncogenesis.

Glycoconjugates and their antibodies are vital components of host-tumor interaction. This review concentrates on the oncological implications of research concerning the alpha gal triad; the alpha 1-->3 galactosyl epitope (alpha Gal), the enzyme responsible for its construction, alpha 1,3 galactosyl transferase (alpha 1-3GT), and its associated antibody: anti-gal. Alpha gal epitopes, previously assumed to be absent from human tissue, have been demonstrated on several human cancer cell lines, senescent red blood cells, and Graves' disease thyrocytes. Alpha-gal presence on neoplastic lines is correlated with increased metastatic formation in animal models. The mechanisms of human response to these neoantigens are complex, as natural anti-gal antibodies exist in high titers in normal sera, thus predicting immunological recognition of cells expressing alpha gal epitopes. Hypotheses vary regarding the pathogenic contributions of metastasis-associated phenomena such as de novo expression of alpha gal and its unmasking by desialylation. The means by which alpha gal is sporadically expressed in human tissue remain unknown, as the galactosyl transferase which produces this epitope in constitutively expressive animals has undergone significant mutation at the genomic level in humans. Pathological re-expression is presumed to require permissive changes at a cellular level. Detailing these alterations is a prerequisite to the comprehension of the metastatic phenotype. In this context, the possibility of therapeutic strategies affecting alpha gal expression are also discussed.

Stimulation of 1-(beta-D-arabinofuranosyl)cytosine (AraC)-induced apoptosis in the multidrug resistant human promyelocytic leukemia cell lines with protein kinase inhibitors.

Stimulation of apoptosis induced by 1-(beta-D-arabinofuranosyl)cytosine (AraC) with protein kinase inhibitors (i.e. staurosporine, CGP 41251-a protein kinase C (PKC)-selective staurosporine derivative and protein tyrosine kinase (PKT) inhibitor genistein) was examined in two human multidrug-resistant promyelocytic leukemia (HL-60) cell lines with different cell membrane drug resistance-associated glycoproteins (i.e. HL-60/VCR:MDR1 gene coded Pgp/p170 and HL-60/ADR: MRP gene coded non-Pgp/p190). Staurosporine stimulated AraC-induced apoptosis in the parental drug-sensitive HL-60 cells and both examined multidrug resistant HL-60 sublines. The stimulation of AraC-induced apoptosis by PKC selective inhibitor CGP 412251 and PTK-inhibitor genistein was approximately equal to that of staurosporine in HL-60/ADR cell line. In both parental drug sensitive HL-60 cells and Pgp/p170 positive (MDR1) HL-60/VCR, staurosporine-stimulated AraC-induced apoptosis was higher than that stimulated by the PKC selective CGP 41251 inhibitor, or PTK-inhibitor genistein. These data suggest that the molecular pathway(s) for AraC-induced apoptosis can be activated and stimulated by PKC- and PTK-inhibitors in both examined drug-resistant HL-60 cell lines. Furthermore, these data suggest that although both PKC- and PTK-dependent mechanisms are involved in AraC-induced apoptosis, in the drug-sensitive HL-60 cells and multidrug-resistant HL-60/VCR (Pgp/p170) cells this process is mediated at least partially, also by PKC- and PTK-independent mechanisms, activated by staurosporine.

Leukocyte alkaline phosphatase and serum alkaline phosphatase in patients with metastatic breast and colon cancer.

Peripheral blood leukocyte alkaline phosphatase (LAP) scores and serum alkaline phosphatase (SAP) levels in 70 patients with metastatic breast and colorectal cancer (metastases to the liver, lung, bone and abdomen) and in 18 healthy controls were measured. The mean LAP score in the metastatic cancer patients was significantly higher than in the control group (244 vs. 61) and there was no overlap between the 95% confidence level intervals of the two groups. The mean (SAP) level in the metastatic patients was also higher than in the controls (249 u/l vs. 162 u/l) but the 95% confidence level interval of the controls was inside the 95% interval of the metastatic patients meaning that considerable percentage of the metastatic patients will have a SAP level within the normal range. We conclude that of the two markers, the LAP is the better one for detection of metastatic tumors.

Comparison of fluorescent in situ hybridization (FISH) and the polymerase chain reaction (PCR) for detection of residual neuroblastoma cells.

Residual neuroblastoma (NB) cells in bone marrow or peripheral progenitor hematopoietic cells harvests may be a source of relapse after autologous transplantation in patients with high stage neuroblastoma. Therefore a sensitive method for detecting minimal residual disease (MRD) in the harvested product is important so that an appropriate purging techniques can be applied and optimized. We report on the detection of NB cells by fluorescence in situ hybridization (FISH) for N-myc amplification and compare the sensitivity of FISH with a semiquantitative polymerase chain reaction (PCR) assay. As a model of MRD we used the neuroblastoma cell line IMR-32 diluted with normal peripheral blood lymphocytes. We were able to detect a single NB cell in 1000 normal mononuclear cells by FISH. The PCR method, using ethidium-bromide-stained gels, required at least 10% NB cells to be present for detection of an amplified band of the N-myc oncogene. Thus, FISH is ten to one hundred times more sensitive in detection of N-myc amplification than a differential PCR and thus it is the method of choice for detection of MRD in NB patients.

p53 gene mutation in relation to p53 protein accumulation in male and female breast cancer.

The aim of this investigation was to study the prevalence of p53 gene mutations in male and female breast cancers and to find out the relationship between this event and p53 protein expression. Genomic p53 was amplified by polymerase chain reaction (PCR). Exons 5-8 were screened for mutations using single stranded conformation polymorphism (SSCP) analysis. P53 protein expression was detected by immunohistochemistry (IHC) with the monoclonal antibody DO-1. In female breast cancer, p53 gene mutation was detected in 33% cases in either exon 5 or 6. However, in male, mutation was detected only in exon 6 in 90% cases. On the other hand, p53 protein expression was observed in all of these cases. Moreover, p53 protein immunostaining was observed in some of those cancer tissues, where no mutation was detected in exons 5-8. P53 dysfunction, as indicated by mutation or increased protein expression, common in both male and female breast cancer, but rate of occurrence or site of mutation differ from each other. Our results in male breast tumors indicate a positive correlation between p53 mutation and p53 protein overexpression, whereas the results in female breast tumors indicate an overexpression of p53 protein even without p53 gene mutation. Therefore, it may be presumed that p53 protein accumulation can result primarily from mutation. In addition, stabilization of p53 through binding to other proteins is another possible reason of p53 overexpression.

Effect of tumor excision on NK cytotoxic activity and formation of metastases of Bomirski melanoma in hamsters.

The growth of transplanted Bomirski melanoma in hamsters is accompanied by the decrease of natural killer cytotoxic activity and the formation of metastases. The excision of primary tumors was carried out to examine what was the effect of the growing tumor and its metastases on the host's NK activity. It was found that the excision of primary tumor caused increased NK cytotoxic activity in comparison to that of nonoperated animals although it was still lower than that of healthy hamsters. It is concluded that both, a growing tumor and metastases, exert suppressive effects on NK activity and those effects add up. The pattern of metastases in operated animals was different to that observed in nontreated hamsters.

Biological consequences of E.coli RecA protein expression in the repair defective pso4-1 and rad51::URA3 mutants of S. cerevisiae after treatment with N-methyl-N'-nitro-N-nitrosoguanidine.

RecA protein of E.coli is a multifunctional protein participating in genetic recombination, recombinational repair and mutagenesis. We used E.coli recA gene as a probe for complementation of repair defects after treatment of N-methyl-N'-nitro-N-nitrosoguanidine in the pso4-1 and rad51::URA3 mutants of S. cerevisiae. We tried to find the role of the RecA protein in S. cerevisiae mutants defective in different repair pathways. The RecA protein had no effect on survival of haploid and diploid pso4-1 mutants, but it had a significant effect on MNNG induced mutagenesis, which was increased to the wild type level. No effect of the RecA protein on survival was observed in rad51::URA3 mutant after MNNG treatment. However, in this case the RecA protein decreased the induced mutagenesis. We can suppose that the RecA protein, with its multifunctional enzymatic activity, can bind to special intermediates and initiate function of different repair pathways depending on repair defects of the mutants studied.

Serum soluble IL-2 receptor as a reliable and noninvasive marker of disease activity in patients with hairy cell leukemia.

Hairy cell leukemia is a chronic lymphoproliferative disorder of B-cell lineage. Malignant cells express the interleukin-2 receptor (IL-2R) which is released in vitro as well as in vivo. The sera of patients with hairy cell leukemia contain elevated levels of this soluble receptor (sIL-2R). Sera of 24 patients with hairy cell leukemia were tested for sIL-2R. In 9 patients treated with 2-chlorodeoxyadenosine an improved clinical status was associated with decreasing serum sIL-2R. The maximal rate of decrease of sIL-2R level was observed within the second and the third week after the therapy initiation. Patients with disease progression had an increase in serum sIL-2R level. Our results suggest that serial measurement of sIL-2R level can be used as a reliable, noninvasive means to assess the disease activity and its response to therapy.

The effect of local hrec TNF-alpha administration upon the spontaneous lung metastases in rats with Morris 5123 hepatoma.

The experiment used Morris hepatoma 5123 series growing in muscles of the right hind limb of Buffalo rats. The group I animals were given intratumor 4 doses of TNF-alpha and group II-8 doses of TNF-alpha (10 micrograms/day). Control groups (III and IV) consisted of rats with injected Morris hepatoma, which were given PBS solution instead of TNF-alpha. A decrease in the volume of neoplastic metastases was observed in groups I and II, compared with groups III and IV. At the same time an increase was found in the volume of metastatic tumors in group II (8 x TNF-alpha), compared with group I (4 x TNF-alpha). Histological and ultrastructural analysis of the pulmonary tissue revealed intensified fibrotic reactions and inflammatory infiltrations around the metastatic tumors. The change were much more enhanced in group II, which might affect the results of neoplastic metastatic volume measurements. We concluded that multiple human recombinant TNF-alpha, hrec TNF-alpha, local injections inhibited dissemination of tumor cells and prolonged the survival time of rats up to the 76th day of the follow-up.

Antitumor action of bovine seminal ribonuclease.

Unlike the bovine pancreatic ribonuclease (RNaseA), bovine seminal ribonuclease (BS RNase) displays various biological activities, including antitumor activity, immunosuppressivity, spermatogenicity and embryotoxicity. To learn more about its antitumor effect we tested BS RNase on the growth of 16 cell lines derived from patients with various hematological malignancies. The cells of lymphoid origin were generally more susceptible to BS RNase, administered in the range of concentrations from 2 to 100 micrograms/ml, than the myeloid ones. RNaseA used at the same concentrations did not exert any inhibitory effect. The inhibitory effect of BS RNase persisted in cultured cells after three times wash in complete medium and cell recultivation in fresh medium free of BS RNase. Four cell lines were very little sensitive (KG-1 and U-937) or resistant (JOK and NAMALWA) to BS RNase regardless of their origin. The in vivo antitumor effect of BS RNase was tested on human prostate carcinoma transplanted to athymic nude mice. The daily dose of BS RNase (0.25 mg/20 g) was administered for three weeks except weekends (15 doses) by three different ways (intraperitoneally-i.p., subcutaneously-s.c. and intratumorally-i.t.). Whereas i.p. administration was ineffective, s.c. administration significantly reduced size of the tumors and i.t. administration abolished half of the tumors in treated mice. The average weight of treated mice decreased during the experiment by 10-15%.

Modulatory effect of tempol on toxicity and antitumor activity of 6-mercaptopurine and on P450 cytochrome level.

Low selectivity of contemporary antitumor drugs requires a search for its improvement. In this context, nitroxyl radicals are of interest as promising pharmacological agents. The introduction of nitroxyl radical into the structure of antitumor cytostatics was found to reduce considerably their general and specific toxicity. In this work, we demonstrate a detoxifying effect of tempol upon its combined injection with cytostatics at their absolute lethal dose in the intact mice as well as an improvement of sensitivity of tumor-bearing animals to 6-MP. Tempol is shown to normalize the level of oxidized form of P450 cytochrome in a liver, reduced as a result of the injection of 6-MP.

Phase I/II trial of carboplatin dose escalation in combination chemotherapy with etoposide, bleomycin and GM-CSF support for poor prognosis nonseminomatous germ cell tumors patients.

To determine the maximum tolerated dose (MTD), and therapeutic efficacy of carboplatin (CBDCA) in combination with etoposide and bleomycin (CEB) as initial chemotherapy for poor prognosis germ cell tumors, a CBDCA dose escalation supported with GM-CSF had been performed. Twenty four untreated patients were treated with CBDCA 400 mg/m2 on day 1, etoposide 100 mg/m2 on days 1 to 5 and bleomycin 30 mg on days 1, 3, 5. Four cycles were scheduled at 21-day interval. The first cohort of 6 patients received only initial chemotherapy regimen. In the subsequent cohorts of six patients, the CBDCA dose was increased by 100 mg/m2. A fixed dose and schedule of GM-CSF at 5 micrograms/kg subcutaneously was given on days 6 through 15. Myelosuppression, with neutropenic fever and hemorrhages, was the dose-limiting toxicity at the 600 mg/m2 dose level. The recommended dose of CBDCA is 500 mg/m2. Overall complete response (CR) rate was 71% and with median follow up of 25 (16-34) months, 58% of patients are alive and have no evidence of disease (NED). A higher number of CR was achieved with CBDCA dose higher than 400 mg/m2 compared with CBDCA dose of 400 mg/m2 (92 vs. 50%, p = 0.03), as well as a higher proportion of patients who are alive and with NED (75 vs. 42%, p = 0.1). Despite GM-CSF support, the MTD of CBDCA could not be increased beyond 500 mg/m2 (50% of the dose escalation), due to severe myelosuppression. The treatment outcomes obtained with CEB in our study are no better than the standard cisplatin-based chemotherapy. Further studies of this regimen, where CBDCA dose should be calculated according to the patients glomerular filtration rate are warranted.

Case-control study of pancreatic cancer in Serbia, Yugoslavia.

Case-control study comprised 100 pancreatic cancer patients and the same number of hospital controls individually matched with cases by sex, age and place of residence. According to logistic regression analysis following factors were found to be risk factors for pancreatic cancer: smoking 26 or more cigarettes per day (OR = 43.95, 95% CI = 7.69-192.53), consumption of 5 or more glasses of hard drinks per week (OR = 12.84, 95% CI = 2.13-77.29), coffee consumption during a period exceeding 35 years (OR = 2.50, 95% CI = 1.18-5.28), gall bladder disease in personal history (OR = 4.29, 95% CI = 1.08-16.99) and family history positive on peptic ulcer (OR = 11.71, 95% CI = 0.99-137.98). Two factors appeared to be protective for cancer of pancreas: appendectomy (OR = 0.22, 95% CI = 0.07-0.68) and blood type 0, Rh+ (OR = 0.25, 95% CI = 0.09-0.61).

Placental isoferritin-associated p43 in pregnancy and breast cancer. Minireview.

Ferritin, physiologically an iron-storage protein, has been repeatedly investigated with regard to its role in the development of inflammation and malignancy [2, 3, 6]. The structural heterogeneity of this protein has aroused considerable interest in recent years [2, 3, 5, 6]. Although ferritin is generally regarded as an iron-storage protein, small amounts are also found in the sera of normal individuals, while abnormally high concentrations are found in the serum of patients with malignancies as well as in pregnant women. In the past, considerable attention has also been paid to the structural heterogeneity of ferritin derived from various organs and malignant tissues [3, 5]. It has been reported that the placenta, fetal tissues and malignant tissues contain acidic ferritin, while the liver and the spleen contain ferritin in the basic form. The acidic isoform has been summarized under the term oncofetal ferritin, since these forms share certain physical-chemical characteristics. These so-called oncofetal or placental ferritins (PLF) have repeatedly been shown to have an inhibitory effect on hematopoiesis and T-cell function [2, 6, 7, 10]. The purpose of the present review is to elucidate current data concerning the role of placental isoferritin in pregnancy as well as in the development of breast cancer.

Immunosuppressive activity of lymphocyte mitogenesis by breast cancer-associated p43.

Placental isoferritin (PLF), an acidic isoform of ferritin, and its unique superheavy chain of 43 kDa (p43) has been described to be synthesized by human breast cancer cells. Physiologically, p43 PLF produced by the placenta is involved in immune suppression of maternal lymphocytes aimed at fetal antigens. A study was carried out to elucidate a paradigm of p43 occurrence in breast cancer patients. Immunosuppression of cytotoxic CD8+ lymphocytes was measured via inhibition of blast transformation in concanavalin A (ConA) stimulated peripheral blood lymphocytes (PBL) using 3H-thymidine uptake in vitro. PBLs were cultivated from 29 women having benign lesions in the breast as well as from 41 patients with breast adenocarcinoma. In breast cancer patients addition of p43 significantly inhibited the activation of lymphocytes proliferation by ConA compared to women with benign tumors. The addition of indomethacin or levamisole did not influence this inhibitory effect of p43 in breast cancer patients. Presence of interleukin-2 in cultures was able to overcome the inhibitory effect of p43 on CD8+ lymphocytes proliferation from women having breast adenocarcinomas and to increase its value in patients with benign lesions.