Organomercury (II) complexes with anti-carcinogenic agents. II. Anti-neoplastic activity.

Organomercury(II) complexes of the type, p-MeOC6H4HgL1 (I), p-NO2C6H4HgL2 (II), p-MeOC6H4HgL3 (III) and p-MeC6H4HgL4 (IV) (HL1-6-mercaptopurine, HL2-6-thioguanine, HL3-5-fluorouracil, L4-phenyldithiocarbazate) have been screened against the following cell panels: leukemia, non-small cell lung cancer, small cell lung cancer, brain cancer, melanoma, ovarian cancer and renal cancer. The variation in anti-neoplastic activity has been correlated with the structural parameters of the complexes.

Decreased sensitivity of multidrug-resistant tumor cells to cisplatin is correlated with sorcin gene co-amplification.

A set of multidrug resistant (MDR) murine leukemia P388 sublines processing 30-50-fold mdr1 gene amplification was obtained as a result of experimental chemotherapy with rubomycin, ruboxyl, vinblastine, vincristine, or combination of rubomycin and vincristine. Significant differences of developed MDR sublines in response to treatment with cisplatin, tiophosphamide, sarcolysin, and dopad were found. Strong correlation between drug sensitivity and a copy number of gene coding for 19-22 kDa calcium-binding sorcin gene co-amplification were hypersensitive to cisplatin and alkylating agents, the cell sublines showing amplification of sorcin DNA sequences did not possess such collateral sensitivity and even acquired cross-resistance. The dependence of sensitivity to cisplatin on sorcin gene co-amplification was confirmed by analysis of Djungarian hamster DM15 cell sublines that selected for MDR in vitro by colchicine.

Radiotherapy plus fifth day carboplatin in locally advanced bladder cancer.

The goal of our prospective nonrandom study was to improve treatment results in advanced bladder cancer and possibility of cure with acceptable toxicity and reduced rate of late complications. Fifty-three patients with locally advanced bladder cancer (clinical stage T3a and b) treated by radical radiotherapy (65 Gy, conventional fractionation) and concomitant carboplatin (150 mg in bolus infusion, once a week, every fifth day an hour prior to the irradiation, up to total dose of 900 mg, during the treatment course. Out of 53 evaluable patients, complete response was achieved in 47/53 (88.7%) and partial response in 2/53 patients (3.8%). Hematological toxicity grade I and II occurred in the majority of patients. Mean follow-up was 16 months (range 4-24), 2-year overall survival has been achieved in 85% and disease free survival of 49 responding patients in 84%.

Gene therapy for cancer (present status).

The present status of cancer gene therapy is reviewed here in short. Two of the main gene therapy strategies for the treatment of cancer are discussed. The first main strategy is direct gene therapy which involves insertion of a functioning tumor suppressor gene or suppression of expression of a known oncogene. The second main strategy is indirect gene therapy which involves the insertion of a gene that modifies the cell to be more immunogenic for the host. The main clinical gene therapy trials are reviewed in their present state, including the replacement of defective tumor suppressor genes, the insertion of suicide or sensitivity genes, the insertion of prodrug-activating genes, and the use of virally directed enzyme prodrug therapies. Other topics discussed are the protection of stem cells from toxic effects of chemotherapy and new directions for gene therapy of neoplastic disease.

Galectin-3, a laminin binding protein, fails to modulate adhesion of human melanoma cells to laminin.

Galectin-3 is a laminin binding protein which expression is altered in a variety of human carcinomas including colon, breast and endometrium. In these tumors, we consistently observed a down regulation of galectin-3 expression related to increased aggressiveness. Galectin-3 belongs to a family of galactose-binding lectins and binds laminin through its numerous poly-N-acetyllactosamine chains. To date, the exact role of galectin-3 in the complex interactions between cancer cells and laminin has not been clearly defined. Adhesion of melanoma cells to laminin is a critical event during tumor invasion and metastasis. In this study, we explore the possibility that galectin-3 could modulate attachment of two human melanoma cell lines to laminin. A2058 and A375 melanoma cell expressed galectin-3 on their surface as demonstrated by immunofluorescence, and attached to laminin in an in vitro assay. We demonstrate that neither recombinant galectin-3 nor an affinity purified antigalectin-3 antiserum altered adhesion of A2058 or A375 melanoma cells to laminin. Our data strongly suggest that galectin-3 is not a key element in adhesion of the melanoma cells to laminin. These results are not surprising in light of the observation that galectin-3 expression is down regulated in cancer and that increased adhesion to laminin is a constant feature of invasive cancer cells.

Immune phenotype and some enzyme patterns in phorbol ester-induced chronic lymphocytic leukemia cells.

Leukemic cells from 10 patients with B-chronic lymphocytic leukemia (B-CLL) were isolated and cultured in the presence of 12-0-tetradecanoylphorbol 13-acetate (TPA) at a concentration of 8 x 10(-7) mol for 72 hours. Cells were analyzed before cultivation and after 72 h of cultivation with and without TPA for changes in surface membrane (Sm) and cytoplasmic (cyt) markers expression, presence of receptor for mouse rosette forming cells (MRFC) and some enzyme profiles. All B-CLL cases studied showed typical B-cell phenotype. TPA treatment induced hairy cell leukemia (HCL) characteristics, given by the membrane CD22 and CD25 expression and TRAP positivity in the majority of the cases tested. Cells had hairy cell-like morphology with more intensive cytoplasmic immunoglobulin (CIg) fluorescence staining, absent receptor for MRFC and increased activity of purine nucleosidephosphorylase. In common these changes indicate that TPA can induce hairy cell characteristics on B-CLL cells in vitro suggesting the more mature differentiation stage of HCL compared with CLL. Furthermore, we originally demonstrated that the CD22, present in the cell membrane after TPA, could be detected in the majority of unaffected B-CLL cells in their cytoplasm. From the technical point of view some intracellular CD markers and Igs of B-CLL cells in viable cells in suspension assayed by flow cytometry are described in this study.

Human hematopoietic cell lines: a model system for study of minimal residual disease detection technique in acute leukemia.

Double immunofluorescence studies using both surface and cytoplasmic antigens were performed on cells of some human hematopoietic lines. We tested several permeabilization protocols in order to optimize, improve and simplify flow cytometric assay to detect the combinations of two markers present in one cell which could be regarded as leukemia-related markers. It was found, that buffered formaldehyde-acetone (BFA) fixation renders the cell membrane permeable without destroying surface antigens so that intracellular and cell surface markers could be measured simultaneously by flow cytometry. Cell lines used for the experiments reported here included MOLT4 T cell line, mature B cell lines DAUDI and U-266, and early B cell line REH-6. Results from our studies demonstrated, that in the absence of CD3 antigen on the surface membrane of viable MOLT4 blast cells, double labeling of fixed, permeabilized cells revealed 97% mCD7+, cCD3+ double positive cells. Two color staining with anti-CD19 and anti-CD22 monoclonal antibodies (MoAbs) in DAUDI cells showed, that larger part of cCD22+ cells expressed mCD19 antigen. CD22 antigen was absent on DAUDI cell membrane. Of great interest was the finding, that the marker detected by anti-CD19 MoAb which was absent on the membrane of U-266 cells was detected in their cytoplasm. Double staining of these cells revealed, that the number of mCD22+, cCD19+ double positive cells was 80%. Cytoplasmic CD22 antigen along with surface membrane CD19 was used to define early B cell line REH-6 as well. Our results demonstrate majority of double positive cells among tested population (mCD19+, cCD22+). To our knowledge the presence of cytoplasmic IgM detectable by flow cytometry in REH-6 cells, which could be so regarded as a precise and adequate counterpart to pre-B acute leukemia cell phenotype in children, is an original finding. Immunological typing plays an important part in the multiple marker analysis of hematopoietic malignancies. Through these surface and cytoplasmic marker combinations minor neoplastic cell populations could be detected. Human hematopoietic cell lines could serve as a reliable model system for monitoring minimal residual disease in acute leukemia patients.

p53 expression in breast cancer related to prognostic factors.

In this article the results of molecular marker p53 examinations were presented in relation to the following established breast cancer prognostic factors: age, histologic type, histologic grade, lymph node involvement, tumor size as well as estrogen a progesterone receptor status. Twenty one percent of these primary breast cancer specimens exhibited the overexpression of p53 protein. Significant associations were found between p53 overexpression and younger age, high histologic grade and low content of estrogen and progesterone receptors. Identification of p53-positive breast carcinomas potentially represents a clinically useful indicator of breast cancer aggressiveness.

DNA index as prognostic factor in breast cancer.

Enzymatically dissociated cells exhibited growth in most cases while mechanically dissociated cells did not grow in short term cultures and were not suitable for cytometric study. Breast cancer cells obtained by enzymatic dissociation were examined for DNA content and S-phase fraction. The most of the primary and metastatic breast cancer cells were aneuploid. The 74% rate of invasive and 62% of primary breast cancers had aneuploid (> G0/G1) DNA content, 22% of metastatic breast cancer cells and 37% of primary tumors cells were DNA diploid or near diploid tumor stemlines. The means of DNA diploid and near diploid tumor cells were higher in primary tumors. DNA index was higher in more aggressive and metastatic tumors. S-phase fractions were higher in cells of metastatic tumors than those in primary tumors. Nuclear DNA content and S-phase fraction can be considered a valuable prognostic indicators in breast cancer.

Micronucleus assay in three transplantable mouse tumors.

The cytokinesis-block micronucleus (MN) assay was performed in three mouse tumors: two sarcomas (SaL, MCA) and Lewis lung carcinoma (LLC). To determine the optimal culture durations and cytochalasin B (cyt-B) concentrations to yield the highest proportion of binucleate cells (BC) for each tumor, the influence of the cyt-B concentration (1, 2 and 3 micrograms/ml) and culture duration (24-96) were studied. The amount of BC and the MN frequency was investigated for the different radiation doses (0-4 Gy). Dose response curves were constructed using the optimal culture duration and cyt-B concentration for each tumor. This was 24 h of incubation for MCA and 48 h for SaL and LLC and 2 micrograms/ml of cyt-B. The tumors examined differ in the mean number of spontaneously (0 Gy) occurring MN in binucleate cells. These were 0.008, 0.022 and 0.044 for MCA, SaL and LLC, respectively. The MN frequency increased with radiation dose. LLC was found to be the most radiosensitive, while MCA proved to be the least radiosensitive tumor. The average number of MN/BC at 2 Gy of irradiation (after subtraction of the value at 0 Gy) ranged from 0.05 to 0.36. The highest mean value -0.36 was shown in LLC, the middle-0.20 in SaL, and the lowest-0.05 in MCA tumor. After higher doses of irradiation numerous BC with two and more MN were found in LLC tumor, while they were not frequently observed in MCA tumor. We did not observe an increase in the MN frequency with culture duration or proliferation rate of the tumor cells. MCA has the shortest potential doubling time (Tpot) and had the lowest MN frequency from three examined tumors. The MN assay has promise to be a rapid predictive assay of radiosensitivity.

Phorbol ester (TPA)-induced differential modulation of cell surface antigens in human pluripotential leukemia (K-562) cell line: effects of protein kinase inhibitors with broad- and PKC selective inhibitory activity.

Phorbol ester (TPA)-induced increase in cell surface expression of adhesion structures, i.e. intercellular adhesion molecule-1 (ICAM-1, CD54), beta 2 integrin LFA-1 (CD11a), complement-regulatory cell membrane protein-protein (CD59) and leukocyte common antigen (CD45) in human erythroid/myeloid leukemia cell line K-562 was inhibited by staurosporine, an inhibitor with broad, non-selective protein kinase inhibitory profile, but not by CGP 41,251, a benzoylated staurosporine derivative with the selective protein kinase C (PKC) inhibitory activity. Neither staurosporine nor CGP 41,251 modulated TPA-induced down-regulation of transferrin receptor (CD71). These data suggest that phorbol ester-induced cell surface antigen modulations in K-562 cells are predominantly mediated by PKC-independent signalling pathways.

In vitro antileukemic activity and chemical transformation of the 5'-chloro-5'-deoxy derivative of cyclocytidine.

Hydrochloride of 5'-chloro-5'-deoxy-cyclocytidine (Cl-cC) is an analogue of cyclocytine hydrochloride (cC), a prodrug of the compound with the strong antileukemic activity arabinosylcytosine (araC). This paper is devoted to the study of its cytotoxic activity in vitro and to the effect of acid and alkaline conditions and temperature on its stability. Cl-cC inhibits not only the growth of L1210 leukemia cells in vitro and the DNA synthesis (IC50 = 0.09 mumol/l) but, at the same time, it has a weak effect on RNA synthesis (IC50 > 250 mumol/l) and no effect on proteosynthesis. In alkaline conditions Cl-cC is transformed to 5'-chloro-araC and 2',5'-anhydro-araC but is more stable in acid solutions.

Assessment of antimutagenic effects of stobadine dihydrochloride on MNNG-induced mutations in Chinese hamster cells V79.

Mutagenicity of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and antimutagenic effect of antioxidant stobadine (STB) were investigated by so called HGPRT/V79 system. Cells were treated by STB before, during and after MNNG-treatment. Our results showed that the highest antimutagenic effect of STB was observed if the drug was given as a pretreatment before exposure of cells to MNNG. This effect was not concentration-dependent within the framework of 1.5-9 mmol. All other combinations of MNNG- and STB-treatment led to the weaker but statistically significant decrease of 6-TGr mutations. Inhibition of proteosynthesis induced by methylxanthine pentoxifylline in the time of pre-MNNG-treatment removed completely antimutagenic effects of STB. In addition to mutagenicity assays, cytotoxicity of STB and combined effects of MNNG and STB were studied. Trypan blue exclusion and growth activity of influenced cells showed that the application of STB (1.5 mmol) before or after MNNG (0.5 microgram/ml) treatment had a similar toxic effect as MNNG alone. Application of STB during MNNG-treatment or pretreatment of cells with STB followed by combined treatment of cells by STB+MNNG statistically significantly decreased viability of cells. There are probably no relationships between the antimutagenic and the toxic effects of combined influence of STB and MNNG on V79 cells.

Increased antioxidant enzyme activities in the colorectal adenoma and carcinoma.

Most colon carcinomas are preceded by an adenomatous polyp--adenoma-carcinoma sequence. Active oxygen species (AOS) can play a role in the pathogenesis of this process. Antioxidant enzymes (AE) are the primary defense against the deleterious effect of AOS. Activities of AE in 56 individuals with colorectal adenoma (CA), 29 individuals with colorectal carcinoma (CC) and in 24 control subjects were examined. Biopsy specimens from the non-neoplastic colonic mucosa and from the CA and CC were taken during colonoscopy for histological and enzymological analysis. Activities of following AE were estimated: CuZn-superoxide dismutase (CuZn-SOD), catalase (CAT) and glutathione peroxidase (GPx). It was found that individuals with CA and CC were characterized by: (1) increased activities of CAT and GPx in non-neoplastic mucosa, that persisted in some of the patients even after removal of tumors; (2) increased activities of CuZn-SOD, CAT and PGx in CA and CC tissues. It can be inferred that the accumulation of peroxides in the non-neoplastic colonic mucosa induced higher activities of CAT and GPx. The reasons of high activities of all AE in the tissues of CA and CC and their relation to carcinogenesis are not clear and require further studies.

Comparison between serum levels of carcinoembryonic antigen, sialic acid and phosphohexose isomerase in lung cancer.

The identification and application of quantifiable tumor markers as adjuncts to clinical care is a story of both success and failure. The present study compared serum levels of carcinoembryonic antigen (CEA) with total sialic acid/total protein (TSA/TP) ratio and phosphohexose isomerase (PHI) in 192 untreated lung cancer patients as well as 80 age and sex matched controls (44 non-smokers and 36 smokers). CEA values were significantly raised (p < 0.001) in smokers as compared to the non-smokers; whereas, TSA/TP and PHI values were comparable between the two groups of the controls. All the biomarkers were significantly elevated (p < 0.001) in untreated lung cancer patients as compared to the controls. Receiver operating characteristic curve analysis revealed higher sensitivities of TSA/TP and PHI as compared to CEA at different specificity levels between 60% and 95%. Mean values of CEA, TSA/TP and PHI were higher in non-responders compared to the responders. The results indicate that TSA/TP and PHI are superior tumor markers than CEA for lung cancer patients.

Cancer, cardiovascular mortality, and diet in Italy and the Czech Republic.

A descriptive study aimed at comparing mortality and dietary patterns in Italy and the Czech Republic was conducted in the period 1970-1990. Mortality from all causes, all cancers, selected site specific cancers and cardiovascular diseases were found to be generally higher in the Czech Republic than in Italy. The North-South gradients observed within Italy have diminished in the course of the last twenty years, mostly due to a less contained decrease of the mortality from cardiovascular diseases and to a marked increase in cancer mortality for Southern regions compared to Central and Northern regions. The mediterranean diet with many health promoting, possibly protective components, mostly of vegetable origin, is consumed in most parts of Italy, particularly in the South. In contrast, a Central European diet abounding in animal products and lacking in fresh fruit and vegetables is generally followed in the Czech Republic. These differences in diet may play a role in the origin of the observed differences in mortality patterns. Some factors other than diet, such as smoking habits, alcohol consumption, endogenous factors, and occupation, that are not considered here, are known to be involved in the causation of some types of cancer. The results of this study are compatible with the hypothesis of a relevant role played by dietary and other life-style habits in the etiopathogenesis of neoplastic and cardiovascular diseases.

Smoking habit and benign breast disease.

The possible association between cigarette smoking and the risk of benign breast disease (BBD) was assessed in a case-control study conducted in Gdańsk, Poland, between 1990 and 1994. The study compared 160 women with newly diagnosed BBD admitted to the Gdańsk Cancer Outpatients Clinic and 160 controls, women from outpatients clinics at the Medical University of Gdańsk. There was no convincing evidence of an association, either positive or negative, between various indicators of smoking habit (smoking status, number of cigarettes smoked per day, duration of smoking) and the risk of BBD. Slightly lower relative risks (RRs) of BBD in ex-smokers of 10 or more cigarettes per day (RR = 0.9; 95% confidence interval, CI: 0.4-2.2), and with duration of smoking > or = 20 years (RR = 0.8; 95% CI: 0.1-3.4), were also observed in current smokers (RR = 0.8; 95% CI: 0.4-1.5), and (RR = 0.8; 95% CI: 0.1-3.4), but these findings were not statistically significant.

The pathogenesis and conservative management of radiation injuries.

DNA-mediated gene transfer into mammalian cells and cancer.

DNA-mediated introduction of genes into mammalian cells promises to be a powerful method for detecting sequences that control cell growth, confer resistance to toxic drugs, code for surface receptor proteins, or, indeed alter cell phenotype in any clearly defined way. The identification and molecular cloning of human transforming genes from neoplastic cells was enabled by the advances in existing techniques that allow DNA-gene transfer. Some methods of gene transfer which are inefficient today, should not be disregarded in the future. Every study of the genetic basis of cancer at the molecular level is an important step to the ability to influence human cancer cells and suppress their growth in vivo.

Relation of some enzyme activities and argyrophilic proteins in childhood acute lymphoblastic leukemia.

In a series of 61 children with newly diagnosed acute lymphoblastic leukemia (ALL) the detection of argyrophilic proteins (AgNORs) in relation to enzymatic profile of leukemic blasts was undertaken. The method of silver staining was used to determine the number of AgNORs per nucleus of cells. The activity of 5'nucleotidase, acid phosphatase and beta-glucuronidase was assessed. The AgNOR proteins quantity varied with immunophenotype and cytochemical profile of leukemic cells. The enzyme 5'nucleotidase is known to be the marker enzyme in beta-precursors ALL and acid phosphatase in T-ALL blast cells. Activity of beta-glucuronidase emerged in lymphoblasts of some cases of ALL in close relation to increased number of AgNOR proteins per nucleus of leukemic cells. Our study indicates the possible importance of beta-glucuronidase involvement and increase AgNOR quantity in the proliferative activity of leukemic cells and thus they are of value in monitoring the risk groups of leukemic patients.

A comparison of some leucocyte differentiation markers and the adenosine deaminase and purine nucleoside phosphorylase values in B and T cell leukemias and lymphomas.

Peripheral blood, bone marrow and/or lymph nodes of 77 patients with T- and B-ALLs/lymphomas were characterized for their surface membrane marker profiles using flow cytometry and fluorescence microscopy. Purine metabolism enzyme activities were compared with membrane immunophenotypes. T and B-ALLs/lymphomas subtypes were defined by the expression of surface membrane antigens detected by the monoclonal antibodies. Based on immunophenotyping we found the following characteristic marker profiles: in T-ALL-CD7, CD2, CD1, CD5, CD3, CD4, CD8, CD38, CD71; in T-NHL-CD7,CD2,CD3,CD4,CD5,CD6; in pre-B ALL-CD10, CD19, CD24, HLA-DR, CD34, in B-ALL-CD19, CD20, CD24, HLA-DR, SmIg with kappa or lamda light chains; in B-ALL-weak SmIg, kappa or lambda, CD19, CD20, CD24, CD5, HLA-DR; in B-NHL-CD19, CD20, CD22, CD24, CD5, more intensive SmIg, kappa or lambda. The cells of leukemic cases tended to have more immature phenotypes than those of lymphoma cases. Analysis of purine metabolism enzyme activities showed that there was a correlation between the values of adenosine deaminase (ADA) and purine nucleoside (PNP) and various types of T- and B-ALLs/lymphomas. ADA levels in B-NHL and B-CLL were lower than those in normal cells, while ADA level in T-ALL, T-NHL, pre-B-ALL and B-ALL was higher (the average 185,92,73,63 pkat. 10(-6)cells, respectively). ADA activity was significantly different between lymphocytes of control group and T-ALL(p<0.01), between T-ALL and T-NHL(p<0.05), between T-NHL and B-NHL(p<0.05) and between T-ALL and B-NHL(p<0.05). PNP activities were lower to those in normal cells. ADA/PNP ratio increased mostly in T-ALL, less in T-NHL, pre-B-ALL and B-ALL (10.8 and 5.3 and 2.2, and 2.0 respectively). ADA/PNP ratio was significantly different between T-ALL and pre-B-ALL(p<0.05) and between T-ALL and B-NHL(p<0.05).

Potential carcinogenicity of homoisoflavanoids and flavonoids from Resina sanguinis draconis (Dracaena cinnabari Balf.).

Polarographic behavior of three homoisoflavanoids and four flavanoids isolated from the dragon's blood (Resina sanguinis draconis. Dracaena cinnabari Balf.), collected at Sokotra, was investigated in aprotic solution and an index of potential carcinogenicity tg alpha was determined. Generally, homoisoflavanoids and flavanoids were reduced in two two-electron steps, the first being reversible and the second one irreversible. The parameter tg alpha values indicated that the majority of these compounds possesses no or only marginal potential carcinogenic activity. However, it was demonstrated that some structural modifications in basic flavonoid structure lead to changed electrochemical properties and a substantial increase of derivative potential carcinogenicity.

DNA repair in Escherichia coli: the dual function of uvr genes.

It has been shown earlier that the starvation of E. coli for both amino-acids and thymine applied prior to UV irradiation inhibits pyrimidine dimer excision without affecting cell survival after UV irradiation. In such cells pyrimidine dimers are tolerated by a rather error-free process that depends on the activity of uvrB, recA and lexA genes. Data presented here show: (a) that the efficient toleration of unexcised dimers requires also the uvrA gene; (b) that the starvation increases the level of RecA protein about 4.7 times; (c) that the effect of starvation on subsequent pyrimidine dimer excision is reversed by a 2 h incubation in complete medium before the cells are UV irradiated. The data suggest that the uvrA, uvrB, recA, lexA dependent nonexcisional repair may be a pathway temporarily functioning in repeatedly damaged cells.

In vitro association of mitochondrial ATP- dependent protease with mitochondrial heat-shock proteins.

Specific antibodies against the mitochondrial ATP- dependent protease and heat-shock proteins were used to study the association of these proteins with an abnormal bacterial protein, CRAG. It was shown that the mitochondrial ATP-dependent protease from rat liver and Zajdela hepatoma bind to the CRAG protein and that this binding was mediated through the heat-shock proteins. It was also demonstrated that the protease associated with heat-shock proteins is capable of degrading large proteins as well as small peptides in an ATP-dependent fashion. Zajdela hepatoma mitochondria, with enhanced mitochondrial proteolysis, were shown to contain more ATP-dependent protease associated with heat-shock proteins.

p53 protein overexpression associates with growth patterns rather than with metastasizing in operable breast cancer.

We have analyzed p53 protein expression in 121 primary breast cancer biopsies by immunohistochemistry using the monoclonal antibody DO-1 and polyclonal serum CM-1. p53 protein overexpression has correlated in our study with mitotic activity (p=0.001), nuclear atypia (p=0.002), less favorable histological type of tumor and in a lesser extent with tumor size. The inverse, but highly significant, correlation (p=0.007) has been observed with lymph node involvement. There was also a trend for higher p53 positivity among DNA aneuploid tumors as compared with DNA diploid cases, but this was not significant. Our study suggests that p53, at least in some patients, may not be directly involved in the process of metastatic progression in breast cancer. Preliminary data would suggest that the detection of p53 protein overexpression could be a useful additional prognostic parameter in breast cancer.

Evaluation of different fixation-permeabilization methods for simultaneous detection of surface, cytoplasmic markers and DNA analysis by flow cytometry in some human hematopoietic cell lines.

Different fixation/permeabilization methods were investigated for their convenience for simultaneous detection of membrane marker/DNA staining or cytoplasmic marker/DNA by flow cytometry. Nine different methods were employed. The expression of membrane marker CD20 and cytoplasmic marker CD22 on BJAB and DAUDI cells and cytoplasmic CD3 on MOLT4 cells were measured. Optimal methods were those that combine paraformaldehyde and saponin (for membrane CD20/DNA staining and cytoplasmic CD3/DNA staining) or buffered formaldehyde-acetone (for membrane CD20/DNA staining and for cytoplasmic CD22/DNA staining). Special interest was focused on proliferation marker CD71 and nuclear antigen Ki67. We investigated CD71 in MOLT4 cells and Ki67 in MOLT4, DAUDI and BJAB cells. Both of these markers are closely associated with proliferation rate. The optimal method for detection of Ki67/DNA staining combines paraformaldehyde with Tween 20.

Analysis of the phenotype and cellular DNA content in some leukemias by flow cytometry.

Phenotype and cell cycle distribution in peripheral blood and bone marrow mononucleated cells was studied in patients with different leukemias: T-ALL, AML, CLL, CML and plasmocytoma. DNA flow cytometry with propidium iodide fluorescence was used. Differences in cell cycle between mononucleated cells from T-ALL and CML patients on one hand and normal controls on the other were seen in peripheral blood but not in bone marrow specimens. Patients with AML, CLL and plasmocytoma showed a cell cycle distribution of mononucleated cells similar to normal controls. DNA content analysis in some leukemias were discussed.

Paclitaxel (Taxol): a review of its antitumor activity in clinical studies Minireview.

The paclitaxel represents first agent from novel class of antineoplastic drugs-taxoids. The clinical development of paclitaxel was initially hampered by hypersensitivity reactions. Current dosage regiments with premedication reduced the incidence of these side effects to less than 3%. The major dose-limiting adverse effect of paclitaxel is neutropenia. Significant activities have been reported in patients with advanced ovarian, breast, non-small cell lung cancer (NSCLC) and head and neck cancer. Combination of paclitaxel with platinum in the treatment of patients with advanced ovarian cancer has a potential to become first-line chemotherapy regimen in the treatment of this disease Long-term follow-up will also allow to determine the effect of the drug on patient survival. The promising results of this drug in the treatment of patients with other malignancies need to be confirmed in ongoing clinical studies.

Serum levels of interleukin-10 and interleukin-6 in patients with lung cancer.

Since the enhanced production of IL-10 by human bronchogenic carcinoma has already been documented, in the present study serum levels of IL-10 were measured serially in patients with lung cancer undergoing radiotherapy. Thirty-one full diagnosed cancer patients underwent the radiotherapy procedures. The interleukin-10 (IL-10) and interleukin-6 (IL-6) serum levels were measured before therapy and after 3, 6 and 12 months after therapy. The interleukins concentrations were evaluated using a solid phase sandwich Enzyme-Linked-Immuno-Sorbent-Assay (ELISA). In all patients the serum levels of IL-10 have been found elevated. Due to the treatment they progressively declined to almost normal ranges in responders, while they remained elevated in non-responders. Serum levels of interleukin-6 have been elevated in the majority of our patients. After 12 months observation they also decreased, mainly in patients responding to the treatment. No correlation between serum IL-10 and IL-6 level has been found. The importance of serum IL-6 determination in lung cancer patients monitoring has already been established. The present study shows, that in spite of still unclear role of IL-10 in the process of carcinogenesis, it may be considered as a prognostic factor in lung cancer.

Serum tumor marker CYFRA 21-1 in the diagnostics of squamous cell lung cancer--comparison with CEA.

The aim of the study was to test the diagnostic value of serum tumor marker CYFRA 21-1 for squamous cell lung cancer (SQCLC) in comparison with carcinoembryonic antigen (CEA). Ninety-one patients were included in this study: 56 with SQCLC-Group I, 25 with other types of lung cancer-Group II, 10 with benign respiratory tract diseases-Group III. Median CYFRA 21-1 serum concentration (ng/ml) was: in Group I: 4.52 (0.94 - > 16), in Group II: 3.58 (1.72 - > 16), in Group III: 2.05 (0.99-3.41). Median CEA serum concentration (ng/ml) was: in Group I: 4.49 (0.76 - > 20), in Group II: 3.32 (1.17 - > 20), in Group III: 3.09 (1.84-6.37). There was a highly significant difference between the levels of CYFRA 21-1 in Group I and III (p < 0.001), but there was no statistically significant difference between the levels of CEA in Group I and III. Sensitivity of CYFRA 21-1 by the cut-off 3.33 ng/ml in the diagnostics of SQCLC was 0.68, specificity 0.90, positive predictive value 0.91, negative predictive value 0.65. Sensitivity of CEA by cut-off 4.61 ng/ml was 0.5 by the same specificity 0.90. CYFRA 21-1 has high sensitivity, specificity and positive predictive value in the diagnostics of SQCLC. Sensitivity of CYFRA 21-1 is significantly higher than sensitivity of CEA in this setting.