Biomedical subjects
Publications and source records attributed to M Bak.
Verrucous carcinoma of the larynx in a middle-aged male patient is reported. The related diagnostic problems are described in detail and clinical and morphological differentiating features from other variants of squamous cell carcinoma are outlined on the basis of literary data and our own experience.
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During continuous treatment with diuretics, the kidney adapts to the initial Na loss by activating antinatriuretic mechanisms which serve to prevent further Na and volume losses. To study the renal sites of adaptations to constant diuretic treatment, bendroflumethiazide (4 mg daily), furosemide (8 mg daily) or vehicle (0.24 ml daily) was infused intraperitoneally to female Wistar rats by implanted osmotic minipumps. Half of the animals (groups vol.) were randomized to receive a balanced saline solution to drink in addition to water in order to replace Na, K and volume losses. On the 6th day of treatment, clearances of inulin, Na, and Li were determined during four consecutive 6 hr periods. Circadian changes in renal excretions occurred in all groups with highest excretions of Na, Li and water in the dark period (6 p.m. to 6 a.m.). Renal changes induced by continuous infusion of diuretics were most pronounced in the dark period and would probably not have been disclosed if the clearance experiments had been restricted to the daytime. The average 24-hour clearance for inulin (glomerular filtration rate) was not different among groups, except for a 20% decrease in the furosemide group. The 24-hour fractional Na excretion, being approximately 0.5% in the vehicle group, increased to approximately 0.8% in group (bendroflumethiazide+vol) and to approximately 2.8% in group (furosemide+vol) but was not different from the vehicle group in the diuretic groups without volume replacement.(ABSTRACT TRUNCATED AT 250 WORDS)
BACKGROUND: In germ cell testicular tumors (GCTT) mdm-2 gene was analyzed for amplification and transcripts but not for protein. The purpose of this study is to determine whether mdm-2 protein level is aberrant in GCTT and if so, what is the relationship between mdm-2 overexpression and other disease parameters including histologic subtypes, p53 status, metastatic potential and clinical stage. METHODS: 81 testicular germ-cell tumors were screened for their mdm-2 expression at the protein levels using immunohistochemistry (IHC) and Western blot (WB) analysis. RESULTS: Of 81 GCTTs 45 (55.55%) showed mdm-2 nuclear immunoreactivity, 34 (41.97%) of which were strongly positive. The incidence of mdm-2 immunostaining was significantly higher (P = 0.0007) in non-seminomas (NSGCT) than in seminomas (SGCT). The frequency of positive tumor was higher in tumors from metastatic patients than in tumors from metastatic-free patients (P = 0.011). mdm-2 expression was detected significantly more frequently in tumors of advanced stages, i.e. IIB, IIC and III versus tumors of early stages (I and II/A) (P = 0.0098). A significant difference between the three stages of disease as to the expression of mdm-2 (chi 2 = 0.0386) could be established, namely the incidence of mdm-2 expression increased with an increase in stage. Using Westem blotting 22 (68.75%) out of 32 tumors overexpressed the mdm-2 oncoprotein of 90 kd (p90). CONCLUSIONS: mdm-2 expression as detected by immunohistochemistry may provide a reliable prognostic tool to isolate subgroups of patients with more aggressive GCTT.
The relationship between the composition of breast cyst fluid (BCF), the menstrual status and in addition some endocrine events in the history of patients (n = 131) with gross cystic breast disease was investigated. The dehydroepiandrosterone (DHA) levels in type II (K+/Na+ < 1) cysts of the follicular group were significantly higher compared to the type II cysts of the luteal or postmenopausal groups. For testosterone a significant difference existed between the type I (K+/Na+ > or = 1) follicular and type I postmenopausal groups. Estrone levels were significantly higher in type I BCF of patients in the luteal phase compared to both the follicular and postmenopausal type I cysts. Progesterone levels were lowest in the postmenopausal subgroups (both in type I and II cyst). Significant correlations were found between the number of pregnancies and the levels of DHA-sulfate and also progesterone in BCF. DHA levels were correlated with the period of lactation. The K+/Na+ ratios were the lowest in women who lactated for the longest period. The estrone was lowest in BCF of current oral contraceptive (o.c.) users while the estradiol was lowest in patients who had never used o.c. A history of previous o.c. use was associated with a significantly high mean DHA level. A significantly higher DHA and lower testosterone level were demonstrated in BCF of patients who had some previous gynecological interventions. The composition of BCF and the "life of cysts" and thus the rate of breast cancer risk may depend on hormonal status during the menstrual cycles or postmenopause and also on endocrine history of patients.
BACKGROUND: The expression of a multidrug resistance associated protein (MRP) has been investigated in a variety of human tumors. However, there is a lack of data regarding its expression in germ cell testicular tumors (GCTTs). PATIENTS AND METHODS: MRP expression was examined by immunohistochemistry (IHC) using mouse monoclonal antibody (MRPm6) against human MRP in 56 testis cancer specimens. This antigen was also correlated with the histology, metastatic behavior, clinical stage and tumor suppressor protein p53 immunostaining of GCTTs. RESULTS: All testis tumors, regardless of their histology, metastatic status and clinical stage gave positive signals. MRP was positive not only in the cytoplasm but, very interestingly, in the nuclei. CONCLUSION: Our results suggested that ala GCTTs express high levels of MRP protein with no relation to any of clinicopathological variables investigated here. Since germ cell tumors are very sensitive to chemotherapy, the role of MRP as mediator of drug resistance seems unconvincing in this malignancy. MRP is located in the cytoplasm and the nuclei of tumor cells and may be involved in transportation and/or redistribution certain substrates from the nucleus to the cytoplasm.
BACKGROUND: This prospective study compares the characteristics of cystic disease of the breast (CDB) of patients who developed breast cancer (BCa) during the follow-up (1.25-4 years) period with those who did not. MATERIALS AND METHODS: K+, Na+, albumin, dehydroepiandrosterone (DHA), DHA-sulphate, oestrone, oestradiol, testosterone and progesterone levels were determined in breast cyst fluid (BCF). Patients presented data about their menstrual status, reproductive history, lactation period, date of first and the number of BCF aspirations, gynaecological interventions, use of oral contraceptives, family history of cancer, smoking habits and coffee consumption. The BCa incidence of patients was compared with the expected number of BCas in an age-matched group of 5143 women. RESULTS: Out of 147 patients 6 developed BCa. The standardized incidence rate was 6.29. There were significant differences in testosterone, oestrone and progesterone levels and also reproductive history of patients who developed BCa compared with patients without BCa. CONCLUSION: The above markers outline a subgroup of patients with the highest BCa risk.
Human epidermoid lung carcinoma xenografts with intrinsic and induced resistance were analyzed with regarding to different parameters. The xenografts with intrinsic resistance to vincristine (HXL 54) and induced drug-resistance sublines to vincristine (HXL 55/VCR), actinomycin D (HXL 55/AD) and cisplatin (HXL 55/DDP) were characterized in terms of the degree of resistance, cross-resistance, proliferation kinetics, tumorigenicity, keratin and P-glycoprotein expression. The results demonstrate that xenografts with intrinsic or induced resistance to vincristine or actinomycin D exhibit a similar general pattern of cross-resistance to that observed in multidrug-resistant cell lines. The resistance cannot be attributed to differences in proliferation kinetics. Development of resistance is associated with loss of tumorigenicity and features of differentiation, P-glycoprotein is little expressed in the resistant xenograft lines and corresponds well with the low grade of resistance.
The histopathology and the expression of various marker substances including cytokeratin, epithelial membrane antigen (EMA) and carcinoembryonic antigen (CEA) of ten human epidermoid lung carcinoma xenograft lines were compared with the corresponding donor patient tumours. It was found that the histological structure and the tumour markers were maintained by the xenografts. Neoplastic cells were more effectively detected using anti-keratin antibodies as compared to antibodies against EMA. CEA immunoreactivity was more common in well differentiated tumours. With the aid of electron microscopy, the known cellular heterogeneity of epidermoid lung carcinomas in man was also confirmed in these xenografts.
The aim of this investigation was to find out whether resistant cells of different tumors can be detected immunocytochemically by the streptavidin-biotin-peroxidase-complex method using the monoclonal antibody 265/F4. This antibody was prepared against the membrane P-glycoprotein of Mr 170 kd from colchicine-resistant CHO cells. For this purpose the acquired resistance of tissue culture cells, ascites tumors and the acquired and inherent resistance of human lung carcinoma xenografts were analyzed. Doxorubicin-resistant S180 cells, daunorubicin-resistant L1210 cells and vincristine-resistant human epidermoid lung carcinoma xenografts showed an intense positive reaction with the monoclonal antibody. In contrast, no specific immunoreactivity was observed with parental (sensitive) tumor cells. These data could eventually provide a prognostic tool for the detection of resistant human tumor cells.
The aim of this investigation was to analyze the resistance to doxorubicin and daunorubicin of murine sarcoma 180 cells grown in vitro (monolayer) and in vivo (ascites form). The colchicine-resistant CHO cells were used as controls. A multidrug-resistant phenotype was found in all investigated cell lines. Multidrug resistant cells grown in tissue culture or as ascites tumor cells needed more time to accumulate rhodamine 123 than their sensitive parental cells. In order to evaluate whether the resistant cells show alterations in the plasma membranes, different methods were applied (immunocytochemistry, immunofluorescence, immunoblotting) using the monoclonal antibodies 265/F4 and C 219. These methods all revealed an increased expression of the glycoprotein Mr 170 kd in the multidrug-resistant cell lines. To determine whether multidrug DNA sequences were expressed in the resistant cell lines, slot blots and Northern blots with RNA of sensitive and resistant cells were performed using the clones pDR 7.8 and pcDR 1.5. Elevated RNA levels were detected in all resistant cell lines.
Thirteen cases of Crohn's disease confined to the vermiform appendix were seen during a 12-year period. They constituted 16.9% of patients with primary resection of the bowel for Crohn's disease in the same period, but only 0.4% of the cases of acute appendicitis. In 10 of the 13 cases there was marked fibrous thickening of the appendiceal wall, and in 11 there were epithelioid cell granulomas. Appendectomy was performed in all cases. None had postoperative fistula or later manifestations of the disease within the observation time averaging 6.3 years. The recurrence rate was previously believed to approach that of recurrence after resection in other parts of the intestines. Collective review of this and three other relatively large case series gave an estimated recurrence rate of 3.5%. We conclude that in Crohn's disease initially confined to the appendix the course appears to be indolent.
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In this study, the activity of the glutathione related enzymes, namely glutathione S-transferase (GST), glutathione reductase (GSSG-R), Selenium-dependent and -independent glutathione peroxidase (GPX) of various TGC tumors (n = 18) obtained from untreated patients, was compared to that of the corresponding enzymes of normal testicular tissues (n = 5). The enzymes of all tumorous tissues except teratomas were significantly less active, than the corresponding enzymes of nontumorous tissues. The GST was in seminomas 4.3-20-, in embryonal carcinomas 47-, and in mixed tumors 13-47-fold less active than in the normal testes. The GST activity of teratomas was about half of that of the normal tissues. The Se-independent GPX, component of GST alfa class, comprised about 90 percent of the total GPX activity in normal testis; however it was absent or barely detectable in all TGC tumors except teratomas. The latter had about the same GPX activity as the tumor-free testicular tissues. Apart from the teratoma, the GSSG-R activity of all TGC tumors was also suppressed to about one third of that of the normal testis. The insufficient function of glutathione related enzymes of TGC tumors may contribute to their sensitivity against treatment. The poorer prognosis of teratomas, however, may be explained by the relatively higher activity of their detoxifying enzymes.
BACKGROUND: The aim of the work was to establish human malignant lymphomas in culture, in order to study the biological characteristics and drug sensitivity of lymphomas of human lymphoid origin. MATERIALS AND METHODS: Lymph nodes of patients were explanted and kept in cultures using conventional tissue culture methods. Cytogenetic methods were used for karyotype analysis. Clonogenic assay was applied to test drug sensitivity. The tumorigenic capacity of the cells was determined by inoculating them into immunosuppressed mice. Immunological and other markers were examined with conventional techniques. RESULTS: A cell line, BHL-89, was established in culture from a patient with B-cell type non-Hodgkin's malignant lymphoma. Cells started to grow after a few days without a feeder layer in stationary suspension. The population doubling time was 48 h. The cells were hyperploid, and non-random aberrations were +1, -15, +14q+. Cloning efficiency in soft agar was found to be as high as 50-60%. The cells expressed markers characteristic of early B cells. The BHL-89 cells were Epstein-Barr nuclear antigen (EBNA) negative. They produced tumors when 10(7) cells were injected into immunosuppressed mice. The cells were sensitive to dibromodulcitol (Elobromol), an alkylating antitumor drug, and resistant to the phorbol ester TPA. CONCLUSIONS: The established EBNA-negative BHL-89 cell line has a few unique characteristics, e.g. rapid establishment without feeder cells, origin from the lymph node of an adult patient, high clonogenicity in soft agar, and resistance to TPA. The cell line is suitable for studying the nature of B lymphomas and testing compounds against lymphoproliferative disorders.
Germ cell testicular tumors (GCTTs) are very sensitive to anticancer treatment. However some patients ultimately die of their disease due to tumor resistance. Multidrug resistance is mediated by the mdr1 gene product P-glycoprotein (P-gp) which is one important mechanism of drug resistance. This study attempted to examine the correlation between P-gp and tumor progression and to evaluate the clinical relevance of P-gp immunoreactivity in patients with GCTT. Expression of the P-glycoprotein was screened in 48 primary human GCTTs, that have not been treated with chemotherapy, using monoclonal antibody (C219) and immunoenzyme staining. Of the samples from 14 seminomatous germ cell testicular tumors (SGCT, 2 seminomas (14%), and of 34 non-seminomatous tumors (NSGCT) 18 (53%) showed high expression of P-glycoprotein. This difference proved to be significant (P = 0.006). The expression of P-gp showed a statistically significant positive correlation with cancers of advanced stages (P = 0.003) and cancers that showed resistance to chemotherapy (P = 0.0052). Detection of P-gp expression in patients with GCTTs before the application of anti-cancer treatment can be used as a useful prognostic marker to isolate patient subgroups with worse prognosis and less susceptibility to chemotherapy.