FOXP1 Expression in Normal and Neoplastic Erythroid and Myeloid Cells.

FOXP1 protein was firstly analyzed in normal tissues, and afterwards in different tumor tissues, mainly carcinoma and lymphoma. In B-cell malignancies, its role was well explored; its expression was shown to be connected with disease prognosis in certain B-non Hodgkin lymphomas. In this study, 16 bone marrow trephine samples from patients with no hematopoietic malignancies and 10 samples from peripheral blood of healthy individuals were immunostained with anti-FOXP1 antibody. Positive cells in bone marrows were not only lymphocytes, but also cells that are immunohistochemically positive for glycophorin C or myeloperoxidase. Peripheral blood samples showed no other positive cells, but small round lymphocytes. Additionally 60 samples from patients with myeloid lineage neoplasms were analyzed. 25 samples from patients with myelodysplastic syndrome (MDS) and 35 patients with myeloproliferative disease (MPD) were double immunostained with anti-FOXP1/anti-glycophorin C and anti-FOXP1/anti-myeloperoxidase antibodies. FOXP1 was found to be expressed in 22 cases of MDS and in none of MPD cases. Its expression in MDS was observed mostly in myeloperoxidase positive cells in contrast to gylcophorin C positive cells. Only two cases revealed both myeloperoxidase positive cells and gylcophorin C positive cells expressing FOXP1 transcription factor. Our results show that FOXP1 is present in normal cells of erythroid and myeloid linages and thus suggest its possible role in development of all hematopoetic cells as well as possible involvement in neoplasm development of myeloid disorders.

Macrophage Infiltration Correlates with Genomic Instability in Classic Hodgkin Lymphoma.

Hodgkin lymphoma (HL) is a biologically diverse group of lymphoid tumors, which accounts for 1% of all de novo neoplasms in the world's population. It is divided into two main groups: the more common classic Hodgkin lymphoma (cHL) and the less common nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL). cHL is further divided into four subtypes, which differ in morphology and the contents of tumor microenvironment. Macrophages are one of the components of tumor microenvironment known to contribute to creating an immunosuppressive microenvironment, which inhibits the activity of cells expressing granzyme B against tumor cells, even when tumor cells are infected with Epstein-Barr virus (EBV). Our research aimed to explore the association between the specific contents of tumor microenvironment and the genetic anomalies in tumor cells. The presence and the relative percentage of cytotoxic T lymphocytes and macrophages was detected by immunohistochemical staining of the antigens specific for certain cell populations. Fluorescent in situ hybridization was used to detect anomalies in the genome of tumor cells and in situ hybridization was used to detect the presence of EBV. Our results show an association between the number of CD163+ macrophages and the number of TP53 copies or BCL6 gene translocation. Patients who had a higher number of CD163+ macrophages infiltrating tumor tissue and three or higher number of copies of TP53 showed poorer survival. We conclude that the presence of macrophages may contribute to genetic instability in cHL, which drives the progression of cHL and decreases survival of the patients.

CD4+/CD57+/CD69+ T lymphocytes and CD14+ dendritic cells accumulate in advanced follicular lymphoma.

Follicular lymphoma is the second most frequent non-Hodgkin's lymphoma, accounting for around 20 % of all lymphomas in Western countries. Initially, it behaves indolently, but in time becomes more aggressive and less susceptible to chemotherapy. Multiple features correlate with the survival of the patients and the progression of the disease, such as therapy with rituximab, tumour microenvironment and the intrafollicular proliferation index. Our research was focused on the association of specific components of tumour microenvironment and the tumour behaviour. The presence and the relative percentage of T lymphocytes, follicular dendritic cells, dendritic cells and macrophages was detected by immunohistochemical staining of the antigens specific for certain cell populations. Our results show that T lymphocytes and dendritic cells affect tumour growth, possibly through interactions with tumour cells. Higher patients' ECOG score and the outcome of the disease are associated with the presence of CD14+ dendritic cells in tumour tissue, while the worse overall survival of patients is associated with the increased number of activated helper T lymphocytes that express marker of exhaustion CD57. Taken together, our results suggest that the efficiency of the immune response against follicular lymphoma depends on more than one type of immune cells. Also, we found that the phenotype of these cells, rather than just their number, affects the tumour behaviour and in consequence survival of the patients.

Different expression of DNMT1, PCNA, MCM2, CDT1, EZH2, GMNN and EP300 genes in lymphomagenesis of low vs. high grade lymphoma.

Tumour cells develop by accumulating changes in the genome that result in changes of main cellular processes. Aberrations of basic processes such as replication and chromatin reassembly are particularly important for genomic (in)stability. The aim of this study was to analyse the expression of genes whose products are crucial for the regulation of replication and chromatin reassembly during lymphomagenesis (DNMT1, PCNA, MCM2, CDT1, EZH2, GMNN, EP300). Non-tumour B cells were used as a control, and follicular lymphoma (FL) and the two most common groups of diffuse large B cell lymphoma (DLBCL) samples were used as a model for tumour progression. The results showed that there are significant changes in the expression of the analysed genes in lymphomagenesis, but also that these changes do not display linearity when assessed in relation to the degree of tumour aggression. Additionally, an integrated bioinformatics analysis of the difference in the expression of selected genes between tumour and non-tumour samples, and between tumour samples (FL vs. DLBCL) in five GEO datasets, did not show a consistent pattern of difference among the datasets.

[The unclassifiable myeloproliferative neoplasm--morphological, cytogenetic and clinical features]. / Neklasificirana mijeloproliferativna neoplazma--morfoloske, citogenetske i klinicke karakteristike.

Myeloproliferative neoplasm, unclassifiable (MPN,U) has clinical, laboratory and morphological features of an MPN but fails to meet the criteria for any of the specific MPN entities. Because overlapping features, morphological findings in bone marrow, BCR-ABL1 fusion gene, V617F JAK2 mutation and cytogenetic abnormalities were analyzed in ten patients diagnosed with MPN,U. Bone marrow biopsy showed hypercellularity with trilineage myeloproliferation, dispersed megakaryocytes with mild pleomorphism and mature nuclei, and absence of reticulin fibrosis. All patients were BCL-ABL1 negative, while V617F JAK2 mutation was found in 6 of 8 patients. Trisomy 8 was found in two patients and t(6;12)(q12;p13) in one patient. Morphological features of MPN,U are nonspecific, however, in study cases they were most similar to diagnostic morphological features of polycythemiea vera. The high frequency of V617F JAK2 mutation in MPN,U cases analyzed revealed that its presence does not confirm a specific type of MPN.

Serum immunoglobulins in non-Hodgkin's lymphoma patients.

Serum proteins and immunoglobulin (Ig) findings in 119 non-Hodgkin's lymphoma (NHL) patients were analysed. Out of them 96 (81%) patients had B non-Hodgkin lymphoma (B-NHL), and 23 (19%) T-NHL. Indolent type of NHL was more frequent (77 patients, 65%), then aggressive type of NHL (42 patients, 35%). Most patients had normal serum protein concentration, the increased protein concentration was seen in 17% of patients while decreased concentration was noticed in 7% of patients. Hypoalbuminaemia was more frequent (43%) then hyperalbuminaemia (1%). In contrast to albumin, low levels of other protein fractions (alpha1-, alpha2-, and beta-globulin) were rather rare (0.6%, 4%, and 3% of patients, respectively) and high levels were frequent (23%, 37%, and 8%, respectively). Polyclonal hyperimmunoglobulinaemia was more frequent finding than hypoimmunoglobulinaemia. In 29% patients higher IgG level and in 25% patients higher IgA level were found. IgM hypoimmunoglobulinaemia (22%) was more frequent than IgG (11%) and IgA (8%) hypoimmunoglobulinaemia. M-spike in serum protein electrophoresis was found in 11 (7%) patients. The statistically significant association was not found between serum Ig concentration and lymphoma malignancy grade as well as between serum Ig concentration and immunologic origin of lymphoma. T-NHL patients have more often IgA concentration level above or under normal values than B-NHL patients (p < 0.05).

Klinefelter syndrome and acute basophilic leukaemia--case report.

Patients with 47, XXY karyotype (Klinefelter syndrome) appear to have increased risk of developing cancer, especially male breast cancer, germ cell tumours and non Hodgkin lymphomas, but rarely acute myeloid leukaemia. We report a patient with acute basophilic leukaemia with 47, XXY karyotype in both the tumour and constitutional cells. Acute basophilic leukaemia is very rare disease comprising less than 1% of all acute myeloid leukaemias. Morphological characteristic of leukaemic blast cells is moderately basophilic cytoplasm containing a variable number of coarse basophilic granules. The most characteristic cytochemical reaction is metachromatic positivity with toluidine blue. Blast are myeloperoxidase negative. Also leukemic blasts express myeloid and monocyte markers. There is no consistent chromosomal abnormality identified in this leukaemia. This is the first reported case of acute basophilic leukaemia in patient with Klinefelter syndrome. In this article the medical history of the patient is given and the possible connection between Klinefelter syndrome and acute myeloid leukaemia is discussed.

FOXP1 expression in monoclonal gammopathy of undetermined significance and multiple myeloma.

Multiple myeloma (MM) is a clonal disorder of terminally differentiated B cells. In some cases the premalignant state is monoclonal gammopathy of undetermined significance (MGUS). Neoplastic plasma cells in both entities carry multiple and complex chromosomal abnormalities that make understanding of the disease development difficult. New insight into malignant mechanisms that underlie multiple myeloma may come from forkhead box P1 transcription factor (FOXP1) analysis in neoplastic plasma cells. FOXP1 is known to be important for B-cell maturation and differentiation and could play a significant role in plasma cell tumors. The purpose of the present study was therefore to analyze FOXP1 protein presence and FOXP1 gene abnormalities in 13 cases of MGUS and 60 cases of MM. It was found that FOXP1 protein was expressed in neoplastic plasma cells, unlike in their normal counterparts, and that additional FOXP1 gene copies could be found in both MGUS and MM. Based on FOXP1 presence in MM and its role in diffuse large B-cell lymphoma and extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue, FOXP1 might play an important role in plasma cell neoplasm.

Prognostic markers and gene abnormalities in subgroups of diffuse large B-cell lymphoma: single center experience.

AIM: To explore the association between FOXP1, BCL2, and BCL6 gene expression in diffuse large B-cell lymphoma tumor cells and their association with the presence of FOXP3 lymphocytes. METHODS: Samples of lymph nodes from 53 patients with newly diagnosed diffuse large B-cell lymphoma were taken at the time of the diagnosis and immunostained for CD10, MUM1, BCL6, BCL2, FOXP1, and FOXP3. Fluorescent in situ hybridization analysis was used for the detection of FOXP1, BCL2, and BCL6 gene abnormalities. The chi(2) test was used for data analysis. RESULTS: FOXP1 protein was detected in 28 cases, genetic abnormalities involving the FOXP1 locus were found in 19 cases, and both were present in 13 cases (chi(2)=7.157; P=0.028). FOXP3 positive cells were detected in 37 cases. There was a significant relationship between BCL2 expression and FOXP1 genetic abnormalities (chi(2)= 5.858; P=0.016) and between BCL2 expression and BCL2 genetic abnormalities (chi(2)= 6.349; P=0.012). There was also an association between BCL6 and FOXP1 genetic abnormalities (chi(2)=8.497;P=0.004). CONCLUSION: There was an association between FOXP1 and BCL2. The presence of FOXP3 positive cells had no influence on any of the analyzed markers.

Prognostic significance of B-cell differentiation genes encoding proteins in diffuse large B-cell lymphoma and follicular lymphoma grade 3.

AIM: To define prognostic significance of B-cell differentiation genes encoding proteins and BCL2 and BCL6 gene abnormalities in diffuse large B-cell lymphoma and follicular lymphoma grade 3 with >75% follicular growth pattern. METHODS: In 53 patients with diffuse large B-cell lymphoma and 20 patients with follicular lymphoma grade 3 with >75% follicular growth pattern the following was performed: 1) determination of protein expression of BCL6, CD10, MUM1/IRF4, CD138, and BCL2 by immunohistochemistry; 2) subclassification into germinal center B-cell-like (GCB) and activated B-cell-like (ABC) groups according to the results of protein expression; 3) detection of t(14;18)(q32;q21)/IgH-BCL2 and BCL6 abnormalities by fluorescent in situ hybridization in diffuse large B-cell lymphoma and follicular lymphoma grade 3 with >75% follicular growth pattern as well as in GCB and ABC groups; and 4) assessment of the influence of the analyzed characteristics and clinical prognostic factors on overall survival. RESULTS: Only BCL6 expression was more frequently found in follicular lymphoma grade 3 with >75% follicular growth pattern than in diffuse large B-cell lymphoma (P=0.030). There were no differences in BCL2 and BCL6 gene abnormalities between diffuse large B-cell lymphoma and follicular lymphoma grade 3 with >75% follicular growth pattern. Diffuse large B-cell lymphoma and follicular lymphoma grade 3 with >75% follicular growth pattern patients were equally distributed in GCB and ABC groups. t(14;18)(q32;q21) was more frequently recorded in GCB group, and t(14;18)(q32;q21) with BCL2 additional signals or only BCL2 and IgH additional signals in ABC group (P=0.004). The GCB and ABC groups showed no difference in BCL6 gene abnormalities. There was no overall survival difference between the diffuse large B-cell lymphoma and follicular lymphoma grade 3 with >75% follicular growth pattern patients, however, GCB group had longer overall survival than ABC group (P=0.047). Multivariate analysis showed that BCL6, CD10, and BCL2 expression, BCL2 and BCL6 abnormalities, and International Prognostic Index were not significantly related to overall survival. CONCLUSION: Diffuse large B-cell lymphoma and follicular lymphoma grade 3 with >75% follicular growth pattern patients have very similar characteristics and their prognosis is more influenced by protein expression of B-cell differentiation stage genes than by tumor cells growth pattern, BCL2 and BCL6 abnormalities, and International Prognostic Index.

Role of MYC in B Cell Lymphomagenesis.

B cell lymphomas mainly arise from different developmental stages of B cells in germinal centers of secondary lymphoid tissue. There are a number of signaling pathways that affect the initiation and development of B cell lymphomagenesis. The functions of several key proteins that represent branching points of signaling networks are changed because of their aberrant expression, degradation, and/or accumulation, and those events determine the fate of the affected B cells. One of the most influential transcription factors, commonly associated with unfavorable prognosis for patients with B cell lymphoma, is nuclear phosphoprotein MYC. During B cell lymphomagenesis, oncogenic MYC variant is deregulated through various mechanisms, such as gene translocation, gene amplification, and epigenetic deregulation of its expression. Owing to alterations of downstream signaling cascades, MYC-overexpressing neoplastic B cells proliferate rapidly, avoid apoptosis, and become unresponsive to most conventional treatments. This review will summarize the roles of MYC in B cell development and oncogenesis, as well as its significance for current B cell lymphoma classification. We compared communication networks within transformed B cells in different lymphomas affected by overexpressed MYC and conducted a meta-analysis concerning the association of MYC with tumor prognosis in different patient populations.

Cervical HPV type-specific pre-vaccination prevalence and age distribution in Croatia.

The main etiological factor of precancerous lesion and invasive cervical cancer are oncogenic human papillomaviruses types (HPVs). The objective of this study was to establish the distribution of the most common HPVs in different cervical lesions and cancer prior to the implementation of organized population-based cervical screening and HPV vaccination in Croatia. In this study, 4,432 cervical specimens, collected through a 16-year period, were tested for the presence of HPV-DNA by polymerase chain reaction (PCR) with three sets of broad-spectrum primers and type-specific primers for most common low-risk (LR) types (HPV-6, 11) and the most common high-risk (HR) types (HPV-16, 18, 31, 33, 45, 52, 58). Additional 35 archival formalin-fixed, paraffin embedded tissue of cervical cancer specimens were analyzed using LiPA25 assay. The highest age-specific HPV-prevalence was in the group 18-24 years, which decreased continuously with age (P<0.0001) regardless of the cytological diagnosis. The prevalence of HR-HPV types significantly increased (P<0.0001) with the severity of cervical lesions. HPV-16 was the most common type found with a prevalence (with or without another HPV-type) of 6.9% in normal cytology, 15.5% in atypical squamous cells of undetermined significance, 14.4% in low-grade squamous intraepithelial lesions, 33.3% in high-grade squamous intraepithelial lesions, and 60.9% in cervical cancer specimens (P<0.0001). This study provides comprehensive and extensive data on the distribution of the most common HPV types among Croatian women, which will enable to predict and to monitor the impact of HPV-vaccination and to design effective screening strategies in Croatia.

Primary mediastinal large B-cell lymphoma: a single-center study of clinicopathologic characteristics.

Primary mediastinal large B-cell lymphoma (PMLBCL) is a subset of LBCL with unique clinicopathologic features. Some studies have raised the question of differences in biological features and clinical course among patients from different parts of the world. We conducted a retrospective clinicopathologic analysis of 24 patients with PMLBCL from a single center in Croatia. We also conducted the first investigation of the frequency of lymphotropic viruses human herpesvirus 6 (HHV-6) and HHV-8 in lymphoid lesions of this disease. The clinical characteristics of the patients were as expected, with high International Prognostic Index scores, elevated serum lactate dehydrogenase (LDH) levels, and bulky disease being adverse prognostic factors. Only 6 patients (25%) showed CD30 expression, and Bcl-6 protein expression was, in our series, prognostically favorable (P = .0401). One patient's tumor had detectable HHV-6 genome sequence, but no HHV-8 sequences were detected in any tumors. Two thirds of the patients received CHOP chemotherapy (cyclophosphamide, hydroxydaunomycin, vincristine, and prednisone) with a relatively low complete remission rate (43.8%; median follow-up, 33.8 months). This study confirmed the moderate preponderance among PMLBCL patients of young females with B symptoms and elevated LDH levels. The CHOP regimen proved effective as first-line therapy only in patients with limited disease. Therefore, other third-generation chemotherapy protocols may be considered for treatment, especially in patients with bulky and advanced disease.

The place and role of serologic methods in detecting Helicobacter pylori infection.

The aim of the study was to determine the place and role of serologic methods in detecting Helicobacter pylori (H. pylori) infection, on the basis of estimated enzyme-linked immunosorbent assay (ELISA) and complement fixation test (CFT) sensitivity and specificity. A total of 549 patients were included in the study. ELISA and CFT as serologic methods were compared with invasive methods (rapid urease test--CLO test, culture, histology). The sensitivity of serologic methods was above 90%, and their specificity was around 80%. Study results confirmed the value, reliability and usefulness of serologic methods in the detection of H. pylori infection.

[Microcellular lung carcinoma in patient with hepatosplenic T-cell lymphoma: a case report]. / Mikrocelularni karcinom pluca u bolesnika s hepatosplenicnim t-stanicnim limfomom: prikaz bolesnika.

Hepatosplenic T-cell lymphoma (HSTCL) is a rare form of extranodal non-Hodgkin lymphoma derived from cytotoxic T-cells, usually manifesting by sinusoidal infiltration of spleen, liver and bone marrow. In 1997 World Health Organization classified malignant lymphomas and placed HSTCL among peripheral T-cell neoplasms. The course of the diseases is usually very agressive with a median survival time of 8 to 16 moths despite multiagent chemotherapy. We present a case of a 48-year-old male patient whose initial symptoms were fatigue, weight loss and night sweats, which were followed by splenomegaly and pancytopenia. After clinical examination we suspected him to have HSTCL which was proved pathohistologically upon splenectomy and it is the first case of this lymphoma diagnosed in "Merkur" Clinical Hospital. As a first line of lymphoma therapy we decided to apply FED course (fludarabine, cyclophosphamide, prednisone), being aware of the published poor results the standard CHOP chemotherapy (cyclophosphamide, doxorubicin, vincristine, prednisolone) yields. As far as we know, the results of this chemotherapy course in the therapy of this tumor have never been published. The patient underwent 6 courses of FED therapy, which he tolerated well and was in good clinical condition. Upon the completion of the 6th course of therapy he was diagnosed with lung anaplastic microcellular carcinoma and was treated with 3 course of PE therapy (cisplatin, etoposide).

[Presence of bcl-2 and p53 proteins in patients with non-Hodgkin's lymphoma at Zadar General Hospital]. / Prisutnost bcl-2 i p53 proteina u bolesnika s ne-Hodgkinovim limfomom u Opcoj bolnici Zadar.

AIM: The presence of bcl-2 and p53 was retrospectively analyzed in 37 previously untreated patients, diagnosed with non-Hodgkin's lymphoma in the period between 1980 and 1998. PATIENTS AND METHODS: According to all positivity in analyzed preparations, all lymphoma were divided into three categories: negative (-) with less than 1 per cent of positive tumor cells for the above-mentioned oncogenes; moderately positive (+) with 1 to 50 per cent of positive tumor cells, and extremely positive (+ +) with over 50 per cent of tumor cells. RESULTS: Twenty-seven (73%) patients with non-Hodgkin's lymphoma were bcl-2 negative, seven (19%) were bcl-2 positive (+), and only one (3%) patient was extremely positive for bcl-2. Bcl-2 was present in follicular lymphomas regardless of the intensity, whereas its presence was not recorded in other subtypes of indolent lymphomas. Bcl-2 was moderately positive (+) in six of 11 patients with follicular lymphoma. As for aggressive lymphomas, bcl-2 was present in three patients, one (3%) of them diagnosed with follicular lymphoma grade III and moderately positive (+) bcl-2. The other two patients were diagnosed with diffuse large B-cell lymphoma, with moderate (+) and extreme (+ +) bcl-2 positivity recorded in one patient each. P53 was negative (-) in six (16%), positive (+) in 27 (73%) and extremely positive (+ +) in four (11%) patients. Positive p53 was found in patients with non-Hodgkin's lymphoma regardless of the level of malignancy. CONCLUSION: This study demonstrated that the expression of oncogenes could be determined in the archival material of lymph node biopsy. The results on oncogene expression were consistent with the expected incidence based on other characteristics of the study population.

[Non-Hodgkin's lymphoma: clinical symptoms, therapy and prognosis in 37 patients]. / NE-Hodgkinovi limfomi: klinicke znacajke, terapija i prognoza u 37 bolesnika.

Clinical characteristics and prognostic factors in 37 patients with the diagnosis of non-Hodgkin's lymphoma made during the 1980-1998 period were retrospectively analyzed. Median age was 70 years, and 70% of patients were aged > 60. The disease was classified according to REAL classification. Twenty-seven (73%) patients had B cell lymphoma, and 10 (27%) patients had T cell lymphoma. Indolent lymphoma was diagnosed in 14, and aggressive lymphoma in 23 patients. Performance status as assessed according to the Eastern Cooperative Oncology Group scale was 0 or 1 in 73%, and worse in 27% of patients. The presence of B symptoms was recorded in 49% of patients. Lymph nodes exceeding 5 cm in size were found in 35% of patients. Erythrocyte sedimentation rate > 40 mm/h was recorded in 43%, and hemoglobin values < 125 mg/L in 73% of patients. Leukocytes were within the normal limits, i.e. below 10 x 10(9)/L, in 81%, whereas lymphocytes were within the normal limits in 86% of patients. Thrombocytopenia was recorded in 24%, and bone marrow infiltration at the time of diagnosis in 65% of patients. Complete or partial response rate was achieved by first-line therapy in 73% of patients, whereas 27% of patients failed to respond or their condition worsened. Median of the expected survival was 60 months for indolent lymphomas and 29 months for aggressive non-Hodgkin's lymphoma. Statistically relevant parameters for complete response in univariate analyses are performance status of the patient, International Prognostic Index and platelet count. In multivariate analysis, the only statistically independent prognostic factor is serum lactate dehydrogenase concentration (p = 0.037). The study confirmed the prognostic relevance of the parameters of the patient general condition according to the World Health Organization scale, International Prognostic Index and platelet count for complete response in univariate analyses. The only independent prognostic factor for the survival was serum lactate dehydrogenase concentration. The prognostic value of the International Prognostic Index was also confirmed.

[Helicobacter pylori--introduction and review of research]. / Helicobacter pylori--uvod i pregled istrazivanja.

The discovery of Helicobacter pylori has revolutionized the pathophysiological and clinical approach to gastric and duodenal ulcer. Since the first paper identifying H. pylori was published only 17 years ago, it has been found out that this bacterium causes probably the commonest human infection. Numerous papers published so far have confirmed causal relationship between H. pylori infection and gastritis, duodenal ulcer, gastric ulcer and gastric cancer. If any recent achievement in the world of medicine is to be called revolutionary, then it is the discovery of the role of a spiral bacterium in the etiopathogenesis of gastritis, gastric ulcer, duodenal ulcer and gastric cancer. The discovery of the role of Helicobacter pylori has entirely changed our views and approach to the treatment of patients with stomach disorders. Not only do these discoveries change our actions, but above all our way of thinking. Almost routine diagnostics and treatment of gastritis, gastric ulcer or cancer has been replaced by studies in epidemiology, isolation and eradication of a single bacterium.