Nimesulide and melatonin in mammary carcinogenesis prevention in female Sprague-Dawley rats.

Tumorsuppressive effects of a selective inhibitor of cyclooxygenase-2 (COX-2) nimesulide (NIM) activity and pineal hormone melatonin (MEL) and their combination in two chemopreventive studies of mammary carcinogenesis were evaluated. Mamary tumors in female Sprague-Dawley rats were induced by N-methyl-N-nitrosourea (NMU) and by 7,12-dimethylbenz(a)anthracene (DMBA), respectively. The treatment with NIM (applied subcutaneously twice a week in the dose of 5 mg/kg b.w.) and MEL (given daily diluted in drinking water in concentration 20microg/ml) began several days before carcinogen administration and lasted until the end of the experiment. The tumor incidence, frequency, latency period and tumor volume as parameters of mammary carcinogenesis were evaluated. Moreover, the effect of chemopreventives on body weight, food and water intake were recorded. Changes of selected parameters of lipid and carbohydrate metabolism in the serum and chosen organs were evaluated in the NMU experiment. In the NIM-treated group in the NMU experiment, the tumor incidence decreased by 34.5% (p < 0.05), tumor frequency per group by 40% (p < 0.05) and tumor volume gain by 39% when compared to the control group. Tumorsuppressive effect of MEL was not observed. In DMBA-induced carcinogenesis an oncostatic effect of NIM was not observed; MEL administration decreased tumor incidence by 21.5% (p < 0.05), tumor frequency per group by 22.5% and tumor volume gain by 43.5%. Combined chemoprevention of NIM+MEL was very similar to that of chemopreventives administered alone. MEL lowered food and water intake and body weight gain in DMBA-induced carcinogenesis. It increased glycogen and cholesterol content in the liver, triacyglycerol and phospholipid concentrations in the bone marrow and decreased malondialdehyde concentration at the same tissue of tumor-bearing animals. NIM did not significantly influence the selected metabolic parameters, excepting the decrease in serum glucose concentration in tumor-bearing rats.

Serum glutathione-S-transferase and glutathione reductase activity in head and neck cancer patients.

Glutathione, an antioxidant plays an important role in phase-II detoxification of carcinogens. The levels of reduced glutathione are maintained by glutathione-depleting as well as replenishing enzymes such as glutathione-s-transferase (GST) and glutathione reductase (GR), respectively. Pre and post treatment changes in GST and GR activities in head and neck cancer patients were analysed. Serum GST and GR were analysed from untreated head and neck cancer patients (PT) (n=146), controls with habit of tobacco (VHT) (n=25) as well as without (no) habit of tobacco (NHT) (n=25) and patients with oral precancerous conditions (OPC) (n=50). The cancer patients were followed-up after initiation of anticancer therapy. Follow-up blood samples were collected. Serum GST and GR activities were estimated by highly sensitive and specific spectrophotometric methods. Untreated cancer patients showed elevated mean serum GST and GR activities as compared to NHT. Patients with OPC had declined mean GST activity as compared to WHT and untreated cancer patients. Paired t-test revealed that complete responders (CR) showed significantly elevated GST levels and declined GR activities (p < 0.001) as compared to those in PT. No correlation was found between stage of the disease and GST, GR activity. Paired t-test showed significant decreased in GR activity in nonresponders (NR) treated with radiotherapy (p=0.01). The study suggested that analysis of glutathione and glutathione-depleting enzymes can be helpful for treatment monitoring of head and neck cancer patients.

Comparing whole body 18F-2-deoxyglucose positron emission tomography and technetium-99m methylene diophosphate bone scan to detect bone metastases in patients with non-small cell lung cancer.

Despite advances in morphological imaging, some patients with non-small cell lung cancer (NSCLC) are found to have non-resectable disease at surgery or die of recurrence within a year of surgery. At present, metastatic bone involvement is usually assessed using conventional technetium-99m methylene diophosphate (Tc-99m MDP) whole body bone scan (bone scan), which has a high sensitivity but a poor specificity. We have attempted to evaluate the usefulness of whole body positron emission tomography with 18F-2-deoxyglucose (FDG-PET) for the detection of malignant bone metastases of NSCLC, and to compare FDG-PET results with Bone Scan findings. Forty-eight patients with biopsy-proven NSCLC and suspected to have stage IV disease underwent whole body bone scan and FDG-PET to detect bone metastases. The final diagnoses of bone metastases were established by operative, histopathological findings or clinical follow-up longer than 1 year by additional radiographs or following FDG-PET/Tc-99m MDP bone scan findings showing progressively and extensively widespread bone lesions. A total of 138 bone lesions found on either FDG-PET or Tc-99m MDP bone scan were evaluated. Among the 106 metastatic and 32 benign bone lesions, FDG-PET and Tc-99m MDP bone scan could accurately diagnose 99 and 98, as well as 30 and 2 metastatic and benign bone lesions, respectively. Diagnostic sensitivity and accuracy of FDG-PET and Tc-99m MDP bone scan were 93.4% and 92.5%, as well as 93.5% and 72.5%, respectively. In conclusion, our data suggest that FDG-PET with the same sensitivity and a better accuracy than those of Tc-99m MDP bone scan to detect metastatic bone lesions in patients with biopsy-proven NSCLC and suspected to have stage IV disease.

Deactivation of P-glycoprotein by a novel compound, oxalyl bis (N-phenyl) hydroxamic acid.

A plasma membrane glycoprotein (P-gp) of 170 kd is over-expressed in most of the drug resistant cells. P-gp is encoded in humans by the gene mdrl and is thought to function as a broad substrate ATP-dependent drug efflux pump. P-gp is also present in many types of normal cells. A good number of chemicals inhibit or deactivate P-gp and thus reverse multidrug resistance (MDR). Most of the reported resistance modifying agents (RMAs) are effective in vitro and have adverse effect on the hosts. Hence, the development of nontoxic RMA is of immense importance in the field of cancer chemotherapy. With this end in view, a nontoxic resistance modifying agent, viz., oxalyl bis (N-phenyl) hydroxamic acid (OPHA) has been developed on the basis of the structural commonalities of the reported RMAs. We reported earlier that OPHA reverses doxorubicin resistance in vitro and also reduces glutathione and glutathione S-transferase in a non P-gp expressing cell line. In the present report, the inhibition of P-gp by the compound, OPHA in human cervical cancer cell line, HeLa, has been described by western blotting, study of immunofluorescence and enzyme linked immunofluorescence assay (ELISA). The inhibition of P-gp by OPHA is significantly higher than that of verapamil. The high IC50 values of OPHA against different cell lines indicate the non toxic nature of the compound. This work underscores the possibility of using the present hydroxamic acid derivative as the nontoxic modulator of the MDR phenotype.

Menstrual cycle and hormone receptor status in breast cancer patients.

Hormone receptors in normal breast tissue were reported to be under the influence of cyclic variations of serum hormones during the menstrual cycle. The current study aimed to demonstrate a similar relationship between the phase of the menstrual cycle and hormone receptor status in operable, premenopausal patients with breast cancer. Patients were prospectively categorized according to the first day of last menstrual period into clinically defined follicular/luteal, perimenstrual/mid-cycle and unopposed estrogen/rest of the cycle phases and hormonally defined follicular/luteal phases. Serum follicle-stimulating hormone, luteinizing hormone, estrogen and progesterone levels were determined on the day of the operation. Estrogen and progesterone receptors in the tissues were detected by immunohistochemistry. Eighty-eight consecutive premenopausal patients with breast cancer were included in the study. Estrogen and progesterone receptors were positive in 57 (64.8%) and 40 (70.2%) patients respectively. Forty-nine patients were in follicular, and 39 patients in luteal phases according to serum hormone levels. Estrogen receptor positivity was significantly higher in hormonally defined follicular phase (p=0.025) and also had a tendency to be higher in perimenstrual phase (p=0.048). In contrast, progesterone receptor status was found to be independent of the phases of the menstrual cycle. As a conclusion, hormone receptor status might change during different phases of the menstrual cycle due to a possible effect of the circulating hormones and if it is found as negative, should he re-evaluated concerning the phase of the menstrual cycle in which the operation was performed.

Therapeutic vaccines against HPV16-associated tumors. Minireview.

Human papilloma viruses (HPV) were found to be closely associated with several types of anogenital tumors, particularly with cervical carcinomas (CC). Of more than 100 HPV types characterized until now, 11 have been classified as high-risk types and detected in human tumor tissue by molecular and immunological techniques. Immunological intervention against HPV can be envisaged at two levels, prophylactic and therapeutic. The therapeutic vaccines constructed to counteract tumors which are already developed utilize two nonstructural early proteins coded by HPV, the products of their E6 and E7 oncogenes. These E6/E7 oncoproteins are the only HPV-coded proteins expressed in CC; they are involved in malignant transformation of HPV-infected cells, their presence is necessary for the maintenance of the malignant phenotype of the cells, and their expression correlates with the transforming potential of HPV. Therefore, the E6/E7 oncoproteins are used for the construction of therapeutic vaccines against HPV-associated neoplasms. The purpose of this review is to discuss the results obtained with HPV16 E6/E7 oncoprotein based therapeutic vaccines in animal tumor models, as well as the prospects and limitations of the vaccines.

Effect of drugs affecting synthesis or degradation of connexin on onset or completion of ethylene glycol induced inhibition of intercellular gap junctional communication.

The role of a connexin synthesis and degradation in the onset or completion of the ethylene glycol-induced inhibition of the gap junctional intercellular communication (GJIC) in V79-4 Chinese hamster cell line was studied as a model of an interaction between the cells and a potential tumor promoter. GJIC was assessed on two levels: on the cytophysiological level - the dye coupling method, and on the immunocytochemical level - the immunolabeling of connexin43. The specific activator of connexin synthesis - Dibutyryl cAMP made the onset of the EG-induced inhibition of GJIC slower, but its effect was only temporary. On the other hand it also speeded up the re-establishment of standard values of GJIC after the removal of EG. Although the non-specific inhibitor of protein degradation via proteasomes - leupeptin increased the amount of connexin plaques on cell membranes, its effect on GJIC remained insignificant. The non-specific inhibitors of transcription - actinomycin D and translation - cycloheximide significantly inhibited the re-establishment of the standard values of GJIC after the removal of EG. The results indicate that although the storage of connexins in Golghi complex probably plays the principal role in the control of the gap junctional communication, the extensive changes in GJIC activity depend on the de novo synthesis of connexin per se.

Expression of gene encoding P65 oncofetal protein in acute and chronic leukemias.

In this study we have established conditions for p65 gene expression analysis by reverse transcriptase polymerase chain reaction (RT-PCR). On the basis of this technique we analyzed p65 gene expression in various types of leukemia: acute myeloblastic leukemia (AML) (n=26); acute lymphoblastic leukemia (ALL) (n=26) and chronic lymphocytic leukemia (CLL) (n=40). The highest frequency of p65 gene expression was found in the patients with CLL (66%). No relationship between the expression of p65 gene and clinical stage of leukemia was observed. The lower percentage of positivity (presence of gene transcript) was seen in patients with ALL (42%) and AML (46%).

Detection of 13q abnormalities in multiple myeloma using immunomagnetically selected plasma cells.

Accurate prognostic evaluation of patients with multiple myeloma (MM) is required for their stratification for more adequate therapy. Chromosomal G-banding and interphase fluorescence in situ hybridization (FISH) on cell-nonspecific samples and on myeloma cells selected by magnetic-activated cell separation (MACS) were used to study 13 samples from 12 multiple myeloma (MM) patients. Bone marrow (BM) samples were analysed using three approaches. Standard mitotic samples were prepared and analysed after G-banding. Interphase FISH was performed to detect the 13q14 deletion in unselected BM cells. In parallel, myeloma cells were selected from the BM using the CD138-specific antibody. The high-purity myeloma cell suspension was then analysed by interphase FISH for the 13q14 deletion. Magnetic separation yielded enriched myeloma cell suspensions with the mean viability of 98.0% (range: 97.0%-99.0%), and the purity of 97.6% (range: 87.2%-99.2%) as detected morphologically, and 85.2% (range: 44.8%-98.4%) as detected by immunophenotyping for CD138+ cells. Interphase FISH revealed the 13q14.3 deletion in 5 of 13 (38.5%) of cell-nonspecific samples and in 9 of 13 (69.2%) of enriched myeloma cell suspensions. In conclusion, interphase FISH on immunomagnetically selected MM cells increases the detection of the 13q14 deletion in BM samples from the patients with MM.

Soluble dipeptidyl peptidase IV (CD-26) in serum of patients with colorectal carcinoma.

Dipeptidyl peptidase IV(DPPIV) or CD26 is a widely expressed ectopeptidase with functions in immune response such as the activation of T lymphocytes. It is expressed in the colon mucosal epithelium only when this becomes malignant. The aim of our study is to ascertain the soluble DPPIV/CD26 levels in the serum of patients with colorectal carcinoma, compared with the levels in healthy individuals. From an accrual of 70 healthy individuals and 99 patients diagnosed with colorectal adenocarcinoma, the levels of soluble DPPIV/CD26 were defined by colored enzymatic spectrophotometric response on the Gly-Pro-Paranitroaniline substrate. The patients diagnosed with colorectal cancer have a higher CD26 level than healthy subjects (p<0.05). Of these patients, those with metastatic colorectal disease have a significantly higher soluble CD26 level (p<0.01). It has also been found that patients with high LDH (lactatodeshidrogenase) and CEA (carcinoembrionary antigen) levels show higher CD26 levels (p<0.01) than patients with normal levels of such carcinoma markers.

The analogy in cell immunophenotype and parameters of cell cycle of ectopic thymus, normal thymus, and some acute lymphoblastic leukemia of T-phenotype.

In our study we described the immunophenotypic characteristics of an ectopic thymus found in an eight month old male baby. Comparing with the results of normal thymic cells we did not found any difference or abnormalities in the phenotype. A brief discussion of theories of histogenesis and possible differential diagnosis of ectopic thymus is included. The most common immune pattern of both, ectopic and normal thymuses, was expression of TdT,CD7,cCD3,CD1 and dual CD4/CD8. Early results of immunological examination confirmed by histopathology stated the diagnosis of ectopic thymus and excluded other causes (infection, trauma, neoplasm and congenital abnormalities). The study of both, ectopic and normal thymic tissue provides a perfect model for comparative analysis of some T-acute lymphoblastic leukemia (T-ALL). Both, thymocytes and some cases of our T-ALL (20 of 48 examined T-ALL) had a specific late cortical T-cell phenotype. We observed new qualities of both, thymic cells and T-ALL cells of a late cortical phenotype that resulted in cell populations localized in the so-called "empty spaces", in fluorescence histograms, that might be discriminated from internal T-cell populations with normal antigen expression. An important sign of T-ALL in common is to display aberrant marker combinations and the tendency to drop specific normal T-cell antigens. Aberrant markers were present in our study in a phenotypic group of a late cortical T-ALL in 11 cases (55.0%) of the 20 studied. As aberrant markers we observed mostly CD10, CD34, HLA-DR and CD13. Furthermore, the tendency to drop specific normal T-cell markers could be recognized in one case of a late cortical T-ALL in the form of TCRab and TCRgd absence. DNA analysis did not reveal any changes in proliferation index either in thymocytes (normal or ectopic), or in T-ALL of a late cortical T-cell phenotype. Based on our findings the clinical utility of comparing the results obtained from the immunophenotypic characterization of healthy hematopoietic and leukemia cells can be concluded. An exact and early diagnosis of hematopoietic disorders (ectopic thymus, T-ALL and T-NHL) and identification of identical phenotypic patterns at different times (for more exact minimal residual disease detection during and after therapy) could be obtained.

Complete remission of Bomirski Ab amelanotic melanoma in hamsters treated with the angiogenesis inhibitor TNP-470.

The growth of solid tumors and their metastasis is dependent on the development of new blood vessels (angiogenesis). In our previous studies it was found that angiogenesis inhibitor TNP-470 acting systematically can decrease the rate of growth of transplantable Bomirski Abmelanoma in hamsters. In this study we applied TNP-470 (30 mg/kg) peritumorally from the day when tumor was palpable over 10 days, once daily. Animals were killed 6 months later and examination by autopsy and histological preparations showed the complete remission of transplanted tumor and the lack of metastasis. Thus, Ab melanoma can be effectively cured with TNP-470 angiogenesis inhibitor when the substance is applied locally.

Comparison of prognostic scoring system to tumor node metastases 1992 and 1997 staging systems in gastric cancer patients.

Tumor node metastases staging systems have been widely utilized to predict the prognosis of gastric cancer patients. The current study aimed to compare a prognostic scoring system to tumor node metastases 1992 and 1997 staging systems in predicting the outcome of resectable gastric cancer patients. Patients treated between 1996-1998 were retrospectively evaluated. Tumor depth in the gastric wall, anatomical location and number of metastatic lymph nodes, metastatic to retrieved lymph node ratio, extent of surgical resection, tumor location, type of lymph node dissection, macroscopic appearence and histologic type of tumor were recorded and patients were divided into groups I-III due to their scores. Patients were also staged according to both tumor node metastases systems. Survival data was analyzed by Kaplan-Meier method. For the comparison of power of the three systems in predicting survival, log-rank and Cox regression analysis were respectively used for univariate and multivariate analysis. 163 resectable gastric cancer patients were evaluated. Median follow-up and survival times were 26 and 23 months respectively. Overall 5-year survival was 37.6%. The number of patients in prognostic scoring groups I, II and III was 44, 109 and 10, respectively. According to tumor node metastases 1992 system, 13, 43, 101 and 6 patients were in stages I, II, III and IV while there were 13, 38, 78 and 34 patients in respective stages in tumor node metastases 1997 system. Although tumor node metastases 1992 (p=0.0088), 1997 (p=0.0029) and prognostic scoring systems (p=0.0006) significantly predicted the survival of patients in univariate analysis, prognostic scoring system was found to be superior compared to other two systems in multivariate analysis (p=0.0002). Prognostic scoring system is a practical, reliable and reproducible method that could be used as an adjunct to tumor node metastases systems in predicting survival of resectable gastric cancer patients.

Usefulness of whole body positron emission tomography (PET) with 18F-fluoro-2-deoxyglucose (FDG) to detect recurrent ovarian cancer based on asymptomatically elevated serum levels of tumor marker.

The aim of this study was to evaluate practice usefulness of whole body positron emission tomography (PET) with 18F-fluoro-2-deoxyglucose (FDG) to detect recurrent ovarian cancer based on asymptomatically elevated tumor marker (CA-125) serum levels. Whole-body FDG-PET was performed in 28 patients with suspected recurrent ovarian cancers and asymptomatically increased serum levels of tumor marker (CA-125 antigen) but negative or equivocal other imaging modality results. All of these 28 asymptomatic patients had serum levels of CA-125 antigen >35 U/ml. The final diagnosis of recurrent ovarian cancer was established by operation/biopsy histopathological findings or clinical follow-up longer than 1 year by additional morphologic imaging techniques. Among the 28 patients, the final diagnoses of recurrent ovarian cancers and benign lesions were established in 20 and 8 patients, respectively. FDG-PET accurately diagnosed recurrent ovarian cancers in 19 patients and benign lesions in 7 patients. When asymptomatically elevated serum levels of CA-125 antigen, the diagnostic sensitivity, specificity, and accuracy of FDG-PET to detect recurrent ovarian cancers were 95.0%, 87.5%, and 92.9%, respectively. FDG-PET is a useful technique to detect recurrent ovarian cancers for patients suspected of recurrent ovarian cancers due to asymptomatically elevated serum levels of CA-125 antigen.

Usefulness of mammoscintigraphy with thallium-201 single photon emission computed tomography to differentiate palpable breast masses of young Taiwanese women when comparing with mammography.

Sixty young Taiwanese women with palpable breast masses detected by mammography and/or physical examinations underwent mammoscintigraphy with thallium-201 (Tl-201) single photon emission computed tomography (SPECT) to assess its value for differentiating breast masses. The results showed that 42 of the 45 cases of breast carcinoma were detected by Tl-201 SPECT mammoscintigraphy. Fourteen of the 15 of benign breast lesions were differentiated by Tl-201 SPECT mammoscintigraphy. The diagnostic sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of Tl-201 SPECT mammoscintigraphy were 93%, 93%, 98%, 82%, and 93%, respectively. Thirty-eight of the 45 cases of breast carcinoma were detected by mammography. Twelve of the 15 of benign breast lesions were differentiated by mammography. The diagnostic sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of mammography were 84%, 80%, 93%, 63%, and 83%, respectively. We concluded that Tl-201 SPECT mammoscintigraphy significantly improves the accuracy when comparing with mammography for the differentiating breast cancer in Taiwanese women.

Evaluation of radiation carcinogenesis risk in vertebral hemangioma treated by radiotherapy.

The purpose of this study is to report carcinogenesis risk factor evaluation in vertebral hemangioma patients treated by radiotherapy. Between 1975 and 1995, 29 patients received 20-30 Gy total irradiation dose using conventional fractionation scheme. All the patients had measurements with thermoluminescent dosimeters (TLD 100 ), placed on multiple randophantom sites in vivo within the irradiated volume, to verify irradiation accuracy and calculate carcinogenesis risk factor. Twenty nine still-alive patients who had a minimum 6-year and maximum 26-year follow-up (median 14.34 years) have been evaluated by carcinogenic radiation risk factor on the basis of tissue weighting factors as defined by International Commission on Radiological Protection Publication 60. Reasonable pain relief has been obtained in all 29 patients. Calculated mean carcinogenesis risk factor is 0.6% for single irradiation portals and 0.9% for double irradiation portals in the whole group, whilst no secondary cancer has been detected. Radiotherapy is an effective treatment modality in relieving pain of vertebral hemangioma patients. Estimated secondary cancer risk factor for this benign neoplasm irradiation is not as high as can be feared.

BCNU-DBD (Dibromodulcitol) chemotherapy of recurrent supratentorial anaplastic astrocytomas and glioblastomas.

Our aim was to investigate the effect of BCNU and DBD combined chemotherapy in patients with recurrent malignant gliomas. Forty-six patients were treated with combined chemotherapy. Out of 26 patients with anaplastic astrocytomas 11 were originally low-grade where no postoperative radiotherapy was applied. Fifteen patients with anaplastic astrocytoma responded well to the chemotherapy and 9 survived longer than one year. Median survival time was 14 months. Complete response of recurrent glioblastoma did not occur and only 4 patients survived longer than one year. Median survival time was 7 months. Ratio of patients with response and stable disease was 70 and 55 %, respectively. BCNU and DBD combination proved to be an effective combination for recurrent malignant gliomas. It was remarkable that patients' survival with primary or secondary lower grade astrocytoma were significantly longer than that in patients with glioblastomas. Treatment of lower grade tumors, even at their malignant recurrences is promising.

Penile metastases from urogenital primaries.

Metastatic tumors of the penis are rare. They are usually secondary to primaries of the genitourinary and gastrointestinal tracts. This entity is usually accompanied by distressing symptoms like dysuria, pain, induration, swelling of the penis and priapism, making immediate intervention necessary. Different methods of treatment are used to achieve the palliative effect: local surgical excision, penis amputation, radiotherapy or chemotherapy. Nevertheless, the prognosis is poor, because the disease is already disseminated and in most cases other metastases will occur soon.

JAK/STAT signaling pathways and cancer. Janus kinases/signal transducers and activators of transcription.

Recent highlights in understanding molecular nature of signaling pathways that mediate biological effects of various external stimuli and control number of normal physiological processes of cells such as growth, differentiation, senescence and apoptosis, defined three major groups of proteins which apparently play an essential role in transmitting external signals from surface membrane to target genes in the nucleus. These include Janus kinases (JAKs), signal transducers and activators of transcription (STATs) and their endogenous inhibitors of SOCS family. Their inappropriate functioning and defective cross-talking associate with several human disorders including cancer. There is an increasing evidence that perturbances in STAT proteins are involved in the pathogenesis of some human malignancies. Moreover, cancer-related defective JAK/STAT/SOCS pathways may negatively affect tumor response to the cytokine-based immunotherapy. This article provides an overview of the current knowledge about JAK/STAT/SOCS intracellular signaling cascades with special emphasis on their abnormalities in cancer.

The most frequent APC mutations among Slovak familial adenomatous polyposis patients. Adenomatous polyposis coli.

We screened 46 suspected families from whole Slovakia for familial adenomatous polyposis (FAP) cancer predisposition. Individuals were enrolled to the adenomatous polyposis coli (APC) gene mutations mapping program at the base of previous clinical investigation. We have used the following techniques: heteroduplex analysis (HDA), protein truncation test (PTT), single strand conformation polymorphism (SSCP) and sequencing for the identification and detailed positional analysis of APC mutations. Around 90% of all detected mutations were found being truncated. The most frequent mutations from this collection were located within codons 1309 and 1061 of exon 15 and represented 15% and 7%, respectively of all tested families. The expressive phenotype, large amount of colorectal polyps and congenital hypertrophy of the retinal pigment epithelium (CHRPE) were associated to all mutations within codons 1309 and 1060.

Lipoxygenase inhibitors induce arrest of tumor cells in S-phase of the cell cycle.

Inhibitors of the lipoxygenase pathway of arachidonic acid metabolism represent a potential anti-tumor drugs. These compounds have been found to inhibit the growth and induce the apoptosis of various tumor cells both in vitro and in vivo. In this study, the effects of the lipoxygenase inhibitors esculetin and nordihydroguaiaretic acid (NDGA) on the progression of the cell cycle were investigated in eight mammalian cell lines of different origin. Flow cytometric analyses of cell cycle distribution after staining of DNA with propidium iodide or 7-aminoactinomycin D and DNA synthesis using incorporation of 5-bromo-2'-deoxy-uridine showed that both esculetin and NDGA suppress cell growth by interrupting the progression of cells through S-phase that results in their accumulation in this phase of the cell cycle. The possible mechanisms of these effects and the significance of the findings for the improvement of anticancer therapy targeted on cell cycle is discussed.

Is the central channel of nuclear pore complex really the exclusive gateway for macromolecular transport?

Examination of many nuclear pore complexes revealed in some of them very thin filaments presumably RNA with accompanying proteins, directing from inner nucleus to the edge of the complex. On one representative micrograph it is shown that this strand continues in the same direction through central part of the complex most probably through the peripheral channel. Next route of the strand is through the tunnel of a hollow rod - subunit of the cytoplasmic ring.

A ratio of apoptosis to mitosis, proliferation pattern and prediction of radiotherapy response in cervical carcinoma.

The prognostic significance of apoptotic (AI) and mitotic (MI) indices, and the ratio of these parameters (AI/MI), MIB-1 labeling index (MIB-1LI) and proliferation pattern was studied in 130 (FIGO stage IB-IIIB) squamous cervical cancer patients before radiotherapy. Also the influence of the patients age and tumors pathological features (stage, grade, degree of keratinization) and DNA ploidy on the biological parameters were analysed. AI and MI were assessed on histological sections stained with hematoxylin and eosin, and the MIB-1LI on specimens stained with rabbit anti-human Ki-67 antibody (DAKO Ltd). Sections stained with MIB-1 antibody were used for assessment of the tumor proliferation pattern. The median age of the patients was 55 years (29-80). The median values for MIB-1LI, AI, MI, AI/MI, were: 52.3%, 1.1%, 1.5, and 0.9, respectively. In the univariate analysis median values for cut-off points were used for MIB-1LI, and AI, however, for other parameters significant cut-off points have been chosen. For MI it was 2.6 and for the AI/MI ratio 0.7. The median time of follow-up was 29 months, with a range of 2-145 months. The univariate analysis showed that tumor stage (p=0.7009), grade (p=0.6660) and AI (p=0.9378) had negligible influence on patients survival. However, MI >2.6 (p=0.0442), AI/MI

Immunocytochemical detection of bcl-2 and p53 proteins in B-chronic lymphocytic leukemia patients.

B-cell chronic lymphocytic leukemia (B-CLL) is a disease with variable course and prognosis. It may be important to predict the possible risk of disease progression in individual patients. We have investigated by immunocytochemistry the bcl-2 and p53 protein expression in 53 B-CLL patients at the time of initial diagnosis. All B-CLL cases were bcl-2 protein positive. The relatively high frequency of p53 protein immunoreactivity was observed (17 of 53 cases; 32%). The percentage of bcl-2 and p53 protein positive cells remarkably varied in individual patients. The heterogeneity in the percentage of bcl-2 as well as p53 positive cells showed to be important in the analysis of mutual relation of these proteins. Noteworthy results were obtained when the group of p53 positive B-CLL patients was analyzed according to the percentage of p53 positive cells (less than 20% and more than 20%, respectively). An inverse relationship between a higher accumulation of p53 and repressed bcl-2 expression and vice versa was observed. The male patients (female patients were not assessed because of the limited number of p53 positive cases) with less than 20% p53 immunoreactive cells revealed a high percentage of bcl-2 protein (p=0.0008). The higher incidence (over 20%) p53 positive cells correlated with lowered percentage of bcl-2 positive cells (p=0.0368). When the patients were subdivided according to p53 positivity and negativity, the majority of p53 positive cases were males (82%), with significantly higher WBC count (p=0.0362). No significant effect of higher or lower WBC counts on bcl-2 and p53 expression was observed. However, the expression of bcl-2 protein was significantly higher in female patients under 50 years (p=0.0012). Regarding the patients of age 50, a significant difference in WBC count was shown in males (p=0.0590). The peripheral blood lymphocytes isolated from healthy subjects used as controls, exhibited undetectable, to low proportion of bcl-2 and p53 positive cells. Comparing the percentage of bcl-2 as well as p53 positive cells in controls and those of B-CLL patients, the significant difference for both proteins was observed (p=0.0009 and p=0.0001, respectively). The results of this study indicate that the overexpression of p53 protein may contribute to the downregulation of bcl-2 in a subgroup of our B-CLL patients. Considering the small numbers of tested p53 positive cases, it would be necessary to confirm our findings in a larger cohort of patients with longer follow up. Thus it would be possible to confirm our expectation of a possible value of the simultaneous aberrant expression of bcl-2 and p53 as useful predictors of future aggressive behavior of B-CLL.

Embryotoxicity of cisplatin and a cisplatin-procaine complex (DPR) studied in chick embryo.

Cisplatin is widely used as an antitumor drug. To reduce its toxic side effects in patients, cisplatin has been bound with procaine in a cisplatin-procaine complex (DPR). The lethal and teratogenic effects of cisplatin alone and of complexed cisplatin were determined in the chick embryo in ovo in order to compare their influence on rapidly proliferating embryonic tissues. The embryotoxic (lethal + teratogenic) effect was examined after a single intra-amniotic injection of one of six different doses, ranging from 0.03 to 30.0 microg, on embryonic days (ED) 3, 4 or 5. The minimal embryotoxic dose was lower for cisplatin alone (0.03-0.3 microg) than for cisplatin in the DPR complex (0.3-3.0 microg), suggesting that cisplatin alone is more embryotoxic than complexed cisplatin. Both substances caused malformations in the surviving embryos evaluated on ED 9. These malformations included microphthalmia, microcephaly, hypoplasia of the upper and lower jaw, cleft beak, and haemocephaly. Moreover, heart septum defects and limb reduction deformities were found after exposure to the DPR complex. The embryotoxicity of complexed cisplatin exhibited a stage-response effect. It was highest on day 3 and gradually decreased until ED 5. Such an apparent stage-response effect was not observed for cisplatin alone. The embryotoxicity of procaine hydrochloride - a component of the complex - was also tested. Procaine hydrochloride alone did not produce any embryotoxic effect, not even after a single injection of the maximal tested dose (100.0 microg per embryo). We also examined the protective effect of procaine hydrochloride, whose separate administration at ED 4 was followed by the injection of 0.3 microg cisplatin. We did not observe any protective effect of procaine hydrochloride if injected separately.

Activity of antioxidant enzymes and concentrations of thiobarbituric acid reactive substances (TBARS) in melanotic and amelanotic Bomirski melanoma tissues in the golden hamster (Mesocricetus auratus, Waterhouse).

The activity of superoxide dismutase (SOD) and glutathione peroxidase (GSHPx), as well as the concentration of thiobarbituric acid reactive substances (TBARS) in tissues of transplantable melanoma in the golden hamster were measured and compared. Ten inbred male hamsters were used for the experiment. They were divided into two groups and were given Bomirski melanoma cells subcutaneously. The first group was given melanotic (Ma) melanoma cells. The second group was given amelanotic (Ab) melanoma cells. Thirty days after the transplantation the hamsters were dissected and the tumor tissues were taken and homogenized. A statistically significantly higher activity of the measured antioxidant enzymes was found in homogenates of Ma tumor than in homogenates of the Ab tumor. Activity of SOD is 8% higher in melanotic melanoma, 24% higher in CAT, and 45% higher in GSHPx. Statistically significant differences between TBARS concentrations were not confirmed. The higher activity of antioxidant enzymes in the melanotic tumor is a result of increased generation of oxygen-derived free radicals. It is presumed that it is strictly connected with intensified production of quinone and semiquinone radicals in the process of melanogenesis.

The treatment of acute myeloid leukemia with mitoxantrone, etoposide and low-dose cytarabine in elderly patients - a report of Polish Acute Leukemia Group (PALG) phase II study.

The common dilemma in the treatment of elderly patients with acute myeloid leukemia (AML) is whether to use intensive myelosuppresive therapy with higher risk of treatment related mortality (TRM), but a chance for complete remission (CR), or to treat less intensively in order to prolong survival time with a better quality of life. The aim of this prospective, phase II study was to assess the efficacy and toxicity of low dose combination induction treatment consisted of cytarabine at a dose of 10 mg/m2 every 12 h s.c. for 7 days, VP-16 at a dose of 100 mg/day p.o. for 7 days and mitoxantrone at a dose of 6 mg/m2 i.v daily on days 1-3. Two induction courses were planned. In the group of 44 patients 12 (27%) achieved CR, 4 (9%) patients were in PR and there were 9 (20%) early deaths (ED). Age, performance status, preceding myelodysplastic syndrome, karyotype, WBC and % of blasts in bone marrow were not significant prognostic factors for CR probability. The following initial factors appeared to be related to a shorter duration of survival time from the start of treatment: age >70 (p<0.03), poor performance status (p<0.03), and % of BM blasts 50 (p<0.05). We conclude that, despite promising results in the pilot study the efficacy of this induction treatment is not better than the efficacy of other regimens. The hematological toxicity of this treatment seems to be comparable with "3+7" regimen.

Quadruple cancer, including triple cancers in the head and neck region.

Multiple primary tumors are not rare: they are encountered in 3-5% of malignant tumors. They are particularly frequent in the head and neck [20]. They are most often met with secondary malignant tumors; triple tumors occur in only 0.5%, quadruple tumors in 0.3% of malignant tumors. The possibility of developing a second metachronous cancer 5 years after undergoing treatment of the initial head and neck cancer is approximately 22%. Multiple metachronous tumors often appear 3-4 years after the observation of the primary tumor, or even after 5-10 years in the case of laryngeal tumors. The frequency of multiple primary tumors in the head and neck region supports the "field cancerization" theory, according to which the inducing agents (primarily smoking and alcohol consumption) can initiate the tumorous degeneration at a number of sites in the oropharyngeal region. The authors report on a case in whom surgery for bladder tumor was followed 101 months later by tumor development in the region of the head and neck: 3 such tumors were treated within a period of 21 months. The histologic result on the bladder tumor was transitiocellular carcinoma, while the latter ones were squamous cell carcinomas. Three of the tumors were treated effectively (no local recurrence or metastasis developed), but the fourth led to the death of the patient. The literature on multiple tumors of the head and neck is reviewed, and possible etiologic factors are discussed. It is pointed out that, besides primary and secondary prevention, close observation of these patients is required, repeated panendoscopy of the upper aerodigestive tract and genetic examinations are recommended.

Early predicting recurrent cervical cancer with combination of tissue polypeptide specific antigen (TPS) and squamous cell carcinoma antigen (SCC).

The establishment of new tumor marker combinations including strong lead-time effects in detecting recurrent cervical cancer appears to be warranted. This retrospective study includes 50 patients with recurrent squamous cell cervical cancer after operation or radiotherapy. The serial serum levels of the tumor markers tissue polypeptide specific antigen (TPS) and squamous cell carcinoma antigen (SCC) were determined. Cutoff values of 78.5 U/L for TPS and 1.5 microg/L for SCC were selected according to the 95th percentile of serum concentrations measured in healthy control patients. Comparing with other monitoring modalities, SCC and TPS showed lead-time effective in 27 and 30 cases, respectively. This difference was not statistically significant. The combination of SCC and TPS provided lead-time effects in 42 cases. Our data indicate that combination of TPS and SCC is a valuable tool in the early predicting recurrent cervical cancer.

In vitro chemoresistance profile and expression/function of MDR associated proteins in resistant cell lines derived from CCRF-CEM, K562, A549 and MDA MB 231 parental cells.

Although cellular experiments have elucidated a number of active principles in the study of the multidrug resistance (MDR) phenomena, most of the drug resistant tumor cells were derived from different parental cell lines. This fact limits generalization of some experimental data and conclusions, and therefore we selected and characterized cell lines resistant to various anti-cancer agents derived from four parental cell lines: CEM (human T-lymphoblastic leukemia), K562 (human myeloid leukemia), A549 (human lung adenocarcinoma) and MDAMB 231 (human breast adenocarcinoma). In total we obtained a set of 42 resistant sublines, which is an excellent tool for the future studies of different aspects of MDR. In this study we report on some basic characteristics of these sublines, namely, cross-resistance to other anti-cancer drugs investigated by in vitro MTT assay, expression of MDR associated proteins (Pgp, MRP1, LRP, GST-pi and Topo IIalpha) as well as the functional activity of Pgp and MRP.