The altered expression of α1 and ß3 subunits of the gamma-aminobutyric acid A receptor is related to the hepatitis C virus infection.

The modulation of the gamma-aminobutyric acid type A (GABA A) receptors activity was observed in several chronic hepatitis failures, including hepatitis C. The expression of GABA A receptor subunits α1 and ß3 was detected in peripheral blood mononuclear cells (PBMCs) originated from healthy donors. The aim of the study was to evaluate if GABA A α1 and ß3 expression can also be observed in PBMCs from chronic hepatitis C (CHC) patients and to evaluate a possible association between their expression and the course of hepatitis C virus (HCV) infection. GABA A α1- and ß3-specific mRNAs presence and a protein expression in PBMCs from healthy donors and CHC patients were screened by reverse transcription polymerase chain reaction (RT-PCR) and Western blot, respectively. In patients, HCV RNA was determined in sera and PBMCs. It was shown that GABA A α1 and ß3 expression was significantly different in PBMCs from CHC patients and healthy donors. In comparison to healthy donors, CHC patients were found to present an increase in the expression of GABA A α1 subunit and a decrease in the expression of ß3 subunit in their PBMCs. The modulation of α1 and ß3 GABA A receptors subunits expression in PBMCs may be associated with ongoing or past HCV infection.

Expression of microRNA-155 precursor in peripheral blood mononuclear cells from Hepatitis C patients after antiviral treatment.

Chronic hepatitis caused by Hepatitis C virus (HCV) is the main source of liver cirrhosis, hepatocellular carcinoma, and extra-hepatic diseases. After treatment-induced resolution of hepatitis C, the persistence of HCV RNA in serum and peripheral blood mononuclear cells (PBMCs) is often observed. An expression of the precursor of microRNA-155 (miR-155) called BIC can be the factor responsible for a course of HCV infection. Therefore, we assessed the relationship between BIC expression and HCV RNA status in sera and PBMCs samples of 64 hepatitis C patients treated with interferon alpha(IFN-alpha)+ribavirin. High expression of BIC in PBMCs was determined in 100% of patients that harbored HCV RNA in serum and PBMCs. Further, we found that 83% of PBMCs samples were BIC-positive in a group of patients that eliminated HCV RNA only from serum. The lowest expression of BIC was found in patients that eliminated HCV RNA from both serum and PBMCs.

Primary cutaneous marginal zone B-cell lymphoma in a patient with chronic lymphocytic leukaemia.

Primary cutaneous marginal zone B-cell lymphoma (PCMZL) is a low-grade malignant lymphoma that presents in the skin with no evidence of extracutaneous localization at diagnosis. We present an 80-year-old woman with B-cell chronic lymphocytic leukaemia (CLL) who developed multifocal PCMZL lesions 14 months after CLL diagnosis. PCMZL was clonally similar to the original bone marrow (BM) CLL cells. The specific translocation t(14;18) (q32;q21) with breakpoints in IGH and BCL2 loci was found in a skin specimen, but was absent in BM and peripheral blood (PB) cells. In contrast, a 13q deletion was found in BM and PB CLL cells. The patient was treated with chlorambucil and complete response of PCMZL was achieved. To our knowledge this is the first patient with CLL in whom PCMZL has been diagnosed.

Various dietary fats differentially change the gene expression of neuropeptides involved in body weight regulation in rats.

Various high-fat diets are obesogenic but not to the same extent. The aim of the present study was to investigate the effects of saturated fat n-6 and n-3 polyunsaturated fatty acids (PUFAs) on the central neuropeptidergic system in adult rats. Using reverse transcriptase-polymerase chain reaction and in situ hybridisation, we evaluated the net effect of feeding in these fats, comparing the effects of a high- to low-fat diet, and the diversity of the effects of these fats in the same amount within the diet. We also determined plasma lipids, glucose, insulin and leptin concentrations. Six-week feeding with high-saturated fat evoked hyperpahagia and the largest weight gain compared to both high-PUFA diets. Rats fed high-saturated fat were found to have decreased neuropeptide Y (NPY) mRNA expression in the arcuate nucleus (ARC) and the compact zone of the dorsomedial nucleus (DMHc), unchanged pro-opiomelanocortin (POMC), galanin-like peptide (GALP) mRNA expression in the ARC, as well as melanin-concentrating hormone (MCH) and prepro-orexin (preORX) mRNA expression in the lateral hypothalamus, compared to low-saturated fed rats. By contrast, feeding with both high-PUFA diets increased POMC and GALP mRNA expression in the ARC compared to the corresponding low-fat diet and the high-saturated fat diet. Furthermore, feeding with both low-PUFA diets reduced NPY mRNA expression compared to the low-saturated fat diet exclusively in the DMHc. Uniquely, the high n-3 PUFA feeding halved MCH and preORX mRNA expression in the lateral hypothalamus compared to the other high-fat and low n-3 PUFA diets. In rats fed three high-fat diets, plasma insulin and leptin concentrations were significantly increased and the type of fat had no effect on these hormone levels. Rats fed high-saturated fat had both hyperglycaemia and hypertriacylglycerolemia and rats fed high n-3 PUFA only had hyperglycaemia. The present study demonstrates that various forms of dietary fat differentially change the expression of neuropeptide genes involved in energy homeostasis.

A new recombinant thrombolytic and antithrombotic agent with higher fibrin affinity--a staphylokinase variant. I. In vitro study.

We attempted to construct a new recombinant protein characterized by fibrin-specific properties of plasminogen activation combined with antithrombin and antiplatelet activities. To the C-terminal part of recombinant staphylokinase (r-SAK), which is a promising profibrinolytic agent, we assembled: (i) the Kringle 2 domain (K2) of tissue-type plasminogen activator (t-PA), containing a fibrin-specific binding site, (ii) the RGD sequence (Arg-Gly-Asp) for the prevention of platelet aggregation and (iii) the antithrombotic agent - hirudin. The cDNA for hybrid protein SAK-RGD-K2-Hir was cloned into pESP-3 yeast protein expression vector. The introduction of K2 t-PA, RGD sequence and hirudin into r-SAK molecule did not alter the SAK activity. The plasminogen activation rate (determined by K(M) and K(cat)) of SAK-RGD-K2-Hir was not significantly different from that of r-SAK. Affinity and binding strength of the recombinant protein to fibrin immobilized on the biosensor were higher than to r-SAK. We observed a higher clot lysis potency of SAK-RGD-K2-Hir as evidenced by a faster and more profound lysis of 125I-labeled human fibrin clots. The potency of thrombin inhibition by the hirudin part of the recombinant fusion protein SAK-RGD-K2-Hir was the same as that of r-Hir alone. In conclusion, the results of the in vitro study suggest that the SAK-RGD-K2-Hir construct can be a more potent and faster-acting thrombolytic agent with antithrombin and antiplatelet properties compared with standard r-SAK.

Richter syndrome first manifesting as cutaneous B-cell lymphoma clonally distinct from primary B-cell chronic lymphocytic leukaemia.

Richter syndrome (RS) is a transformation to high-grade non-Hodgkin lymphoma in patients with chronic lymphocytic leukaemia (CLL). RS may develop in lymph nodes or rarely extranodally. Skin localization of RS has been described in only a few cases. We present a 77-year-old woman who developed isolated diffuse large B-cell lymphoma (LBCL) in the skin of the nose without any other symptoms of RS. The LBCL in the skin was clonally distinct from the original bone marrow CLL cells. Moreover, LBCL cells were positive for LMP-1 segment of Epstein-Barr virus and overexpressed p53 protein. The patient was successfully treated with CHOP (cyclophosphamide, doxorubicin, vincristine and prednisone) and adjuvant local radiotherapy.

Abnormalities of the P53, MDM2, BCL2 and BAX genes in acute leukemias.

Abnormalities of the P53 network have been implicated in the pathogenesis of acute lymphoblastic leukemia (ALL) and acute myeloblastic leukemia (AML). The purpose of this study was to define P53 gene mutations, to detect MDM2 gene amplification and to estimate mRNA expression of P53, MDM2, BCL2 and BAX genes in patients with ALL and AML. Twenty-five patients with ALL and 65 patients with AML, both recently diagnosed, were included into this study. Exons 5-8 of the P53 gene with flanking intronic sequence were amplified by the polymerase chain reaction (PCR) method and subjected to mutation screening by single-strand conformation polymorphism analysis (SSCP). Mutation of the P53 gene was found in one patient of the 25 with ALL and in five patients of the 65 with AML. Sequence analysis was subsequently performed. One mutation in intronic sequence in ALL and four missense mutations and one silent nucleotide substitution in AML were identified. Amplification of MDM2 gene was detected by multiplex-PCR analysis in only one sample from patient with ALL, but was not observed in any case of AML. To gain further insight into the role of P53 network in the evolution of acute leukemias, the P53, MDM2, BCL2 and BAX mRNAexpressions in portion samples from patients with ALL and AML were analyzed using multiplex RT-PCR. Although a low frequency of molecular disturbances of the P53 and the MDM2 genes was detected in this study, there was a high percentage of cases with increased mRNA level of P53 and MDM2. A high frequency of BCL2 mRNA overexpression and a relatively low frequency of BAX mRNA overexpression detected in both analyzed leukemias in this study, indicate that altered transcription of these genes may be involved in leukemogenesis.

A comparative study of P53/MDM2 genes alterations and P53/MDM2 proteins immunoreactivity in liver cirrhosis and hepatocellular carcinoma.

In the present study, the expression of P53 and MDM2 proteins were examined in specimens from a group of 20 patients (9 with primary hepatocellular carcinoma HCC and 11 with liver cirrhosis LC, linked to HBV infections as a major aetiologic factor) by immunohistochemistry. The immunostaining findings were correlated with P53 mutation analysis using PCR-SSCP, PCR-HDF and direct sequencing, and MDM2 amplification studies by differential PCR. P53 immunopositivity was found in 9 out of the 20 (45.0%) cases. Mutations of the P53 gene were detected in 5 (55%) tumors and 3 (27%) LC samples; 7 of these cases revealed P53 immunoreactivity. The mutations were base transitions at codons 175, 245 and 273; no changes were observed at codon 249, characteristic for aflatoxins action. MDM2 immunopositivity was revealed in 9 out of 20 (45.0%) specimens. MDM2 amplification occurred in 4 (44.4%) and 1 (9.1%) cases, HCC and LC specimens respectively; only in 2 tumors (10.0%), which exhibited MDM2 immunoreactivity. Overall, MDM2 positivity was not associated with MDM2 amplification in 7 out of the 20 studied samples (35.0%). Two HCC patients were found to have both gene abnormalities. Either the mutation rate of the P53 gene as well as the amplification level of the MDM2 gene was higher in HCC than in precancerous liver tissue stages. These results support the notion that besides P53 alterations, MDM2 gene deregulation seems to be an important event in hepatocarcinogenesis. Additionally, the mechanism of MDM2-mediated degradation of P53 protein, without involving stabilization and inactivation of P53 gene, should be considered for the understanding of all features of tumor progression processes.

Microsatellite instability and expression of DNA mismatch repair genes in malignant astrocytic tumors from adult and pediatric patients.

Microsatellite instability (MSI) is used as a molecular marker for defective DNA mismatch repair (MMR) genes. We report here alterations of MSI in 15 malignant astrocytomas (WHO grade III) and glioblastomas (GBM; WHO grade IV) of pediatric patients (2 - 21 years) and 12 GBM from adults (44 - 68 years) by comparative analysis of BAT25/BAT26 loci and 10 other microsatellite markers. High-level microsatellite instability (MSI-H) occurred in 4 of the 15 pediatric cases (26.7%) and in 1 of the 12 adult GBM cases (8.3%). Low-level microsatellite instability (MSI-L) was observed in 6 pediatric cases (40%) and 8 adult GBM (66.7%). Unstable BAT-25 locus was found in 1 of the MSI-H pediatric cases. Thus, 2 unstable cases showed no instability of this marker. For BAT-26, such a discordance was even more profound: in 1 of MSI-H cases, we obtained no PCR product and the remaining 3 showed no alterations of this marker. MSH2 (Human MutS, Homologue2) protein was detected in all but 3 pediatric cases (1 highly unstable and 2 low-level unstable) and in all adult cases. MLH1 (Human MutL, Homologue 1) protein was detected in all but 2 pediatric cases (1 highly unstable and 1 low-level unstable). Thus, 2 highly unstable pediatric cases showed no detectable MLH1/MSH2 proteins. Our data support earlier observations that MSI occurs predominantly in malignant astrocytic tumors of young patients, which lends support to the hypothesis of different molecular mechanisms of pediatric brain tumors. Surprisingly, we found no significant correlation between the status of 10 microsatellite markers and that of either BAT25 or BAT26 loci or with the expression of MMR genes.

p65 and c-erbB2 genes expression in breast tumors: comparison with some histological typing, grading and clinical staging.

Using PCR technique we have analyzed p65 and c-erbB2 genes expression in 47 frozen tissue slides taken from patients diagnosed as ductal and lobular breast cancer, classified as G3, and in a limited panel of proliferative breast disease cases. Expression of p65 was generally connected with small tumor size and with absence of metastases in regional lymph nodes. We have found interdependence between p65 gene expression and negative states of lymph nodes. On the contrary, c-erbB2 expression was observed in patients with large tumors and with metastases to the regional lymph nodes. Between both genes (p65 and c-erbB2) opposite interdependence was found. No statistical dependence between estrogen/progesterone receptor levels and p65 or c-erbB2 expression were noticed. The presence of p65 expression appeared in the group of proliferating breast disease cases which were connected with higher risk of breast cancer. Lack of p65 expression accompanied cases which were classified as fibroadenoma.

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%).

Successful treatment of leukaemia cutis with cladribine in a patient with B-cell chronic lymphocytic leukaemia.

Cutaneous presentation of B-cell chronic lymphocytic leukaemia (B-CLL) is uncommon, and the influence of skin changes on B-CLL prognosis is unclear. We report a patient with B-CLL Rai II, with multiple nodular skin infiltrations on the trunk, upper arms and thighs as well as constitutional symptoms, who was successfully treated with cladribine. The peripheral blood (PB) lymphocytes were CD19, CD20, CD23 and CD5 positive, which confirmed the diagnosis of B-CLL. Skin biopsy of one of the lesions showed an intense infiltrate composed of small lymphocytes with no epidermotropism. These cells also showed the expression of CD19, CD20, CD23 and CD5 antigens similar to those presented on PB lymphocytes. Polymerase chain reaction performed on bone marrow lymphocytes and a lesional skin biopsy using consensus primers for immunoglobulin heavy-chain genes also showed the same monoclonal population of B lymphocytes both in the bone marrow and in the skin. The patient received four courses of cladribine 0.12 mg kg-1 daily as a 2-h infusion for five consecutive days. The courses were repeated at monthly intervals. The lymphocytosis gradually decreased and the PB count normalized after three courses. At the same time, a significant decrease in the cutaneous symptoms was observed. The patient became free of skin tumours after the fourth course of cladribine; only slight discoloration at the previous sites of cutaneous infiltration remained. There was no relapse of leukaemia cutis during a further 7 months of observation.

Molecular diversity of gammadelta T cells in peripheral blood from patients with B-cell chronic lymphocytic leukaemia.

To characterize circulating gammadelta T cell subpopulations in B chronic lymphocytic leukaemia patients (n=30), TCR Vgamma and Vdelta gene-segment use was analyzed by RT-PCR using a panel of subfamily-specific oligonucleotide primers. All results were compared with those obtained with specimens from healthy donors (n=10). The cells expressing Vdelta1+ TCR displayed the highest relative increase in B-CLL patients (particularly observed in 60% of cases), but Vdelta3+ T lymphocytes also expanded in leukaemic peripheral blood (10% of studied cases). Both mentioned gammadelta T cell subsets were significantly more frequent in the most severe stages of disease--Rai III+IV. The analysis of Vgamma region usage in TCR formation revealed that gammadelta T cells from B-CLL patients predominantly expressed a Vgamma9 segment (26 of 30 cases), usually linked to Cgamma1 region. It should be noticed that the dominant TCR genes expression in a 50% of healthy donors was Vdelta2+/Vgamma9+, however, Vgamma4 and Vgamma8 transcripts were also observed (2 and 3 of 10 cases, respectively). The above results indirectly indicate that gammadelta T lymphocyte expansion was driven by the oligo- or polyclonal proliferation and can reflect specific response against the autologous tumor cells.

Richter's syndrome following cladribine therapy for chronic lymphocytic leukemia first manifested as pathologic fracture of the femur.

Richter's syndrome (RS) refers to the development of aggressive non-Hodgkin's lymphoma (NHL) during the course of chronic lymphocytic leukaemia (CCL). It occurs in approximately 3% of patients with CLL. The isolated form of this complication in bone is extremely rare and, so far, has not been described in a patient treated with cladribine (2-CdA). We report a case of CLL treated successfully with 2-CdA, where isolated diffuse large B-cell lymphoma (LBCL) developed 2 years after the diagnosis of CLL Rai II and one year after the completion of 2-CdA treatment. RS was first manifested as a pathologic fracture of the left femur. The LBCL was clonally distinct from the original CLL cells. The patient was successfully treated with CHOP and radiotherapy and obtained complete response of the LBCL.

Lymphocyctes Tgammadelta in clinically normal skin and peripheral blood of patients with systemic lupus erythematosus and their correlation with disease activity.

Human Tgammadelta lymphocytes constitute from 1 to 15% of all peripheral blood lymphocytes. Recent work has demonstrated that this population plays a major role in the pathogenesis of infectious and immune diseases. Increased numbers of gammadelta T cells have been found in affected skin from systemic sclerosis and chronic cutaneous lupus erythematosus patients. In our study, we have determined the numbers of Tgammadelta lymphocytes and their subpopulations in peripheral blood from 29 patients with systemic lupus erythematosus (SLE) and in 19 healthy volunteers using flow cytometry and specific monoclonal antibodies. The same cells in uninvolved skin from SLE patients and human controls using immunohistochemical analysis were estimated. T-Cell receptor (TCR) delta chain gene rearrangement was identified with primers for Vdelta1, Vdelta2 and Vdelta3 by the polymerase chain reaction. Statistical analysis showed a significantly decreased number of gammadelta T cells in SLE patients (26.4+/-16.9/microl) compared with the control group (55.3+/-20.6/microl (p < 0.001). The number of Vdelta2 TCR+ and Vgamma9 TCR+ subpopulations was also lower in SLE patients than in healthy persons. No statistical correlation between disease activity and the number of gammadelta T cells was demonstrated. The percentage of Tgammadelta lymphocytes in clinically normal skin from SLE patients was twice (22.0+/-9.4%) that found in the skin from healthy persons (11.1+/-5.5%) (p < 0.002). Higher percentages of the Vdelta2 TCR+ and Vgamma9 TCR+ subpopulation of lymphocytes were found in the skin from SLE patients. We have also found positive correlation between the percentage of Tgammadelta lymphocytes in skin and the activity of SLE (r=0.594, p < 0.001), and between subpopulation Vdelta3 TCR+ and disease activity (r=0.659, p< 0.001). In conclusion, the results of our studies demonstrate that, in patients with SLE, accumulation of Tgammadelta lymphocytes can be seen in clinically normal skin, and the percentage of these cells correlates with the activity of the disease.

Low-grade non-Hodgkin's lymphoma in a patient with systemic lupus erythematosus.

Coexistence of systemic lupus erythematosus (SLE) with low-grade non-Hodgkin's lymphoma (LGNHL) has been described occasionally in the literature with the potential pathogenetic role of monoclonal B CD5+/CD19+ cells. We report a case of LGNHL which developed 18 months after diagnosis of SLE. The monoclonal population of lymphocytes in the peripheral blood and bone marrow was CD5/CD19 negative but CD19/CD22 positive. The SLE responded well to treatment with prednisone and the course of the LGNHL was stable and cytotoxic treatment was not required.

[Familial occurrence of nephroblastoma]. / Rodzinne wystepowanie nerczaka plodowego.

Wilms' tumour can develop in ways: sporadic--non-hereditary or familial. Familial Wilms' tumour is not very seldom. It is a form of autosomal dominant segregation and probably low and variable penetration. Up to now it has not been observed in the presence of characteristic genetic changes. Taking into consideration the case of the patient with positive family interview we presented the way of diagnosing and treating the child. Moreover we presented the results of cytogenetic examination and molecular analyses (loss of heterozygosity of WT1 gene and loss of heterozygosity 16 q), which had not shown any changes. We also discussed the actual level of knowledge abut familial form of Wilms' tumour.

Plasmablastic lymphoma in a patient with chronic lymphocytic leukemia heavily pretreated with cladribine (2-CdA): an unusual variant of Richter's syndrome.

Patients with chronic lymphocytic leukemia (CLL) may develop a large-cell transformation known as Richter's syndrome (RS). RS usually presents as diffuse large-cell lymphoma (DLCL) or its immunoblastic variant, and it can be recognized simultaneously with CLL or even 23 yr after its diagnosis. We describe an unusual case of CLL treated with cladribine (2-CdA) in whom DLCL of the plasmablastic type (PBL) developed 4 yr after CLL (Rai IV) diagnosis and 1.5 yr after the 10th course of 2-CdA treatment. Immmunologic, cytogenetic, and molecular studies performed at the time of CLL and PBL coappearance indicated that both tumors originated from different B-cell progenitors. Both malignancies were refractory to VAD (vincristine, doxorubicin, dexamethasone)-based chemotherapy, and only partial response was achieved with CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) salvage treatment. However, the patient died 6 months after the occurrence of RS due to rapid progression of PBL. This is the first description of a CLL patient who developed an unusual plasmablastic variant of RS. Recently, the PBL entity has been identified among DLCL associated with the human immunodeficiency virus (HIV) infection. We suggest that in our CLL patient heavily pretreated with 2-CdA, PBL arose as a second clone due to the prolonged and severe state of the host's immunosuppression. Overall survival with current strategies is poor, and further insight into the natural history, biology, and treatment of PBL are needed.

[Involvement of WT1 gene expression in regulation of P53 and MDM2 proteins function in acute lymphoblastic leukemia]. / Rola ekspresji genu WT1 w regulacji funkcji bialek P53 i MDM2 w ostrej bialaczce limfoblastycznej.

Using sensitive techniques such as reverse transcription polymerase chain reaction (RT-PCR) the expression of WT1 gene in acute lymphoblastic leukemias (ALL) is indicated. High level of mRNA WT1 was only observed in ALL cases with leukemic cells characterized by P53- and MDM2-positive staining in cytometric analysis. The overexpression of P53 protein has not been induced by P53 gene abnormalities and MDM2 protein synthesis was independent from respective gene amplification. The data suggest that WT1 may play a distinct role in the pathophysiology of acute leukemias. It can regulate the function of the main oncoprotein network factors--P53 and MDM2 proteins. There was concluded that the most important mechanism of tissue P53-immunopositivity was connected with the P53 interactions with other oncoproteins, especially with MDM2 and WT1. They have caused different effects in particular cases and several phenotypes of leukemic cells were described. However, the negative tissue staining with anti-P53 monoclonal antibodies can not be evidence of the proper P53 protein function. The immunohistochemical estimations of the P53 level in the cells are insufficient for diagnostic and clinical evaluations. Molecular analyses of P53 and MDM2 genes, as well the WT1 gene transcription, are necessary for the proper characterisation of functional and structural status of P53.

Medullary thyroid carcinoma (MTC)--clinical and molecular aspects on the basis of own experience.

In our clinic 19615 patients were operated over 25 years on for goiter. Malignant thyroid neoplasms were found in 1049 (5.3%) patients including 875 (83.4%) women and 174 (16.6%) men. Sixty two adult patients (42 women and 20 men were operated on for medullary thyroid carcinoma (MTC). Thyroid cancer was diagnosed in this group pre or intraoperatively in 44 (71%) patients and postoperatively, on histologic examination, in 18 (29%) patients. These patients were reoperated. Radical operations (total thyroidectomy with regional lymph node removal) were conducted in 43 (69.3%) patients and palliative ones in 19 (30.7%) patients. After MTC surgery, MEN 2A (MTC and an adrenal tumor) were diagnosed by means of imaging techniques (USG, CT) in 6 (9.7%) patients. All adrenal tumors were unilateral. Five of these patients were operated, and pheochromocytoma was confirmed by histopathologic examination. Two years after the MTC operation, 1 women was lost to follow-up. After a year, she was admitted to hospital for severe hypertension and died of cerebral hemorrhagia. Pheochromocytoma was revealed by autopsy. All patients were treated complementarily after the MTC operation. Different combinations of teleradiotherapy, chemotherapy and substitutive doses of levothyroxine were used. Ten (23.2%) of 43 patients operated radically were reoperated 1-3 years after the first operation due to loco-regional tumor recurrence. Radical reoperations were performed in 4 patients, and palliative ones in 6. Over a 0.5-23-year follow-up period, 26 (41.9%) patients died, including 20 of cancer, and 6 of other reasons. Four out of 36 living patients have clinical or biochemical symptoms of neoplastic disease. The follow-up period of MEN 2 patients operated on ranged from 1 to 6 years. Up to now, no tumor in the second adrenal gland has been diagnosed in any of these patients. Genetic (molecular) tests performed in 31 out of 36 living patients revealed mutations of RET gene in 4 (12.9%).