Metaplasia, intraepithelial neoplasia and early cancer of the stomach are related to dedifferentiated epithelial cells defined by cytokeratin-7 expression in gastritis

Cancer presumably arises from stem cells, preserved in an undifferentiated status since fetal development, or from a dedifferentiation of mature cells that return into a fetal phenotype with the potential for proliferation and renewal. Dedifferentiation in this context could represent a transient phase, passed through by cells, before they switch to redifferentiation, metaplasia or neoplasia. Cytokeratin-7 (CK7) is present in fetal, largely absent in normal adult, and transiently neoexpressed in metaplastic and neoplastic epithelial cells of the stomach according to previous observations. CK7 neoexpression in the stomach could, hence, define a fetal-like, dedifferentiated, cellular phenotype during the development of metaplasia and neoplasia. To test this hypothesis, we investigated CK7 expressions in fetal stomachs, non-neoplastic control stomachs, and neoplastic stomachs exhibiting metaplasia, intraepithelial neoplasia, and early cancer. Proliferation and beta-catenin expression of CK7-positive cells were also evaluated. The chronology of CK7 expression was studied during the experimental gastritis-cancer sequence in Mongolian gerbils. Our results show that metaplastic and neoplastic changes in the gastritis-cancer sequence are related to dedifferentiated epithelial cells which are defined by CK7 expression and can phenotypically be linked to fetal cells at the start of gastric pit development. The dedifferentiated cells exhibit a low proliferation and beta-catenin accumulation, similar to stem cells. Thus, the "stem cell" and "dedifferentiation" hypotheses for cancer origin could complement one another, and dedifferentiation-redifferentiation processes might be decisive for carcinogenesis in the stomach.

Frequency and spectrum of Malassezia yeasts in the area of the prepuce and glans penis

OBJECTIVE

To investigate the frequency and spectrum of lipophilic Malassezia yeasts within the area of the glans penis and preputial space in healthy men, most of whom were uncircumcised.

SUBJECTS AND METHODS

As the glans penis and the prepuce are abundant in sebaceous glands, 130 clinically healthy men were examined for the presence of Malassezia spp. Two impression preparations each were made on modified Dixon (mDixon) and Leeming-Notman agar. The media were used with no added cycloheximide to allow the identification of the full spectrum of Candida yeasts. After 10 days of incubation at 32 degrees C Malassezia and Candida yeasts were differentiated by micromorphological and biochemical criteria.

RESULTS

Malassezia spp. were found as part of the microflora of the glans penis in 49% of the men. The two media yielded comparable results for isolation frequency and spectrum: On mDixon agar, 47.6% of the isolates were identified as M. sympodialis, 42.8% as M. globosa, 4.8% as M. pachydermatis and 2.4% as M. furfur. Candida spp. (especially C. albicans) were found in 20.8%. There were no significant differences in the distribution of different Malassezia spp with age.

CONCLUSIONS

Malassezia yeasts may belong to the resident microflora of the male genital region, which is supported by the finding that free sebaceous glands ('Tyson's glands') normally occur at this site. They may also be involved in pathological processes of the glans penis, e.g. balanitis, seborrheic eczema or psoriasis.

Ki-67 expression and residual tumour (R) classification are associated with disease-free survival in desmoid tumour patients

BACKGROUND

In order to evaluate prognostic factors in the long-term survival of desmoid tumour patients, analysis of clinicopathological, immunohistochemical and follow-up data was performed.

PATIENTS AND METHODS

Between 1969 and 1998, 54 patients underwent resection of aggressive fibromatosis (desmoid) and 33 of them (10 patients with FAP and 23 sporadic) were followed-up with a median time of 130 months (range 10-355 months). Additionally, immunohistochemical analysis of the desmoid tumours using Ki-67 was performed.

RESULTS

In univariate analysis, curative resection (R0) (p<0.001) and low proliferation of Ki-67 (p=0.002) were of significant positive prognostic value concerning disease-free survivaL R0 and absence of Ki-67 staining were significantly associated with each other (p=0.004).

CONCLUSION

Ki-67 seems to serve as a predictive marker concerning disease-free survival of desmoid tumour patients. In patients presenting with Ki-67 positive desmoids, which are unlikely to be resected in a curative manner, alternative treatment (e.g. sulindac) may be preferable.

Covalent strategy for immobilization of DNA-microspots suitable for microarrays with label-free and time-resolved optical detection of hybridization

Sequence-specific detection and quantification of nucleic acids are central steps in many molecular biology procedures which have also been transferred to chip-based procedures. Hybridization-based assays can be used to quantify and discriminate between DNA target sequences down to the level of single base mismatches. Arrays of DNA probes immobilized on a support enable simultaneous testing of multiple sequences of a single sample. DNA arrays can be produced either by in-situ synthesis of oligonucleotides or by immobilization of pre-assembled DNA probes. Covalent and directed immobilization improves the reproducibility and stability of DNA arrays. This is especially interesting with repeated use of transducers or chips. Procedures are described for effective covalent immobilization of pre-assembled amino-linked oligonucleotides, by use of ink-jet techniques, on a modified and heated glass surface, with addressable surface areas ranging from 0.01 mm2 to a few mm2. Almost immediate evaporation of the spotted droplets on the heated surfaces leads to very high surface hybridization capacities. The surfaces are suitable for use with a label-free detection method - reflectometric interference spectroscopy (RIfS). It is shown that hybridization capacity and non-specific interaction at these DNA-surfaces can be characterized by use of RIfS. With a consumption of less than 80 ng mm(-2) oligonucleotide and a specific hybridization capacity of more than 300 fmol mm(-2), the activated aminodextran procedure was usually suitable for setting up a DNA array with label-free detection. Non-specific interactions with random oligomers or protein (ovalbumin) were low. Up to 150 repeated regenerations (stripping) of the surfaces by acid treatment and denaturing agents, and 50 days of storage, have been possible without significant loss of hybridization capacity.

Variable beta-catenin expression in colorectal cancers indicates tumor progression driven by the tumor environment

Invasion and dissemination of well-differentiated carcinomas are often associated with loss of epithelial differentiation and gain of mesenchyme-like capabilities of the tumor cells at the invasive front. However, when comparing central areas of primary colorectal carcinomas and corresponding metastases, we again found the same differentiated epithelial growth patterns. These characteristic phenotypic changes were associated with distinct expression patterns of beta-catenin, the main oncogenic protein in colorectal carcinomas, and E-cadherin. Nuclear beta-catenin was found in dedifferentiated mesenchyme-like tumor cells at the invasive front, but strikingly, as in central areas of the primary tumors, was localized to the membrane and cytoplasm in polarized epithelial tumor cells in the metastases. This expression pattern was accompanied by changes in E-cadherin expression and proliferative activity. On the basis of these data, we postulate that an important driving force for progression of well-differentiated colorectal carcinomas is the specific environment, initiating two transient phenotypic transition processes by modulating intracellular beta-catenin distribution in tumor cells.

Disassembly of microtubules and inhibition of neurite outgrowth, neuroblastoma cell proliferation, and MAP kinase tyrosine dephosphorylation by dibenzyl trisulphide

Dibenzyl trisulphide (DTS), a main lipophilic compound in Petiveria alliacea L. (Phytolaccaceae), was identified as one of the active immunomodulatory compounds in extracts of the plant. To learn more about its biological activities and molecular mechanisms, we conducted one-dimensional NMR interaction studies with bovine serum albumin (BSA) and tested DTS and related compounds in two well-established neuronal cell-and-tissue culture systems. We found that DTS preferentially binds to an aromatic region of BSA which is rich in tyrosyl residues. In SH-SY5Y neuroblastoma cells, DTS attenuates the dephosphorylation of tyrosyl residues of MAP kinase (erk1/erk2). In the same neuroblastoma cell line and in Wistar 38 human lung fibroblasts, DTS causes a reversible disassembly of microtubules, but it did not affect actin dynamics. Probably due to the disruption of the microtubule dynamics, DTS also inhibits neuroblastoma cell proliferation and neurite outgrowth from spinal cord explants. Related dibenzyl compounds with none, one, or two sulphur atoms were found to be significantly less effective. These data confirmed that the natural compound DTS has a diverse spectrum of biological properties, including cytostatic and neurotoxic actions in addition to immunomodulatory activities.

Epstein-Barr virus infection in paediatric liver transplant recipients: detection of the virus in post-transplant tonsillectomy specimens

AIMS

Post-transplant lymphoproliferative disease (PTLD) is an important and serious complication in transplant patients. Recent studies have suggested that quantitative assessment of Epstein-Barr virus (EBV) infection in transplant patients might help to identify those at risk of developing PTLD. Therefore, tonsils from paediatric liver transplant recipients were studied for evidence of EBV infection.

METHODS

Tonsils were studied by in situ hybridisation for the detection of the small EBV encoded nuclear RNAs (EBERs). The phenotype of EBV infected cells was determined by double labelling in situ hybridisation and immunohistochemistry. The expression of viral latent and lytic antigens was determined by immunohistochemistry. Tonsils from patients without known immune defects were studied as controls.

RESULTS

Tonsils from transplant patients showed pronounced follicular hyperplasia and minor paracortical hyperplasia. In situ hybridisation revealed variable numbers of EBV infected B cells in the tonsils from transplant patients (range, 2-1000/0.5 cm(2); mean, 434/0.5 cm(2); median, 105/0.5 cm(2)). Lower numbers were detected in the control tonsils (range, 1-200/0.5 cm(2); mean, 47/0.5 cm(2); median, 9/0.5 cm(2)). The latent membrane protein 1 (LMP1) of EBV was not detected and there were only rare cells in two cases showing expression of the EBV encoded nuclear antigen 2 (EBNA2). There was no evidence of lytic infection. None of the patients developed PTLD within a follow up period of up to five years.

CONCLUSIONS

These data indicate that tonsillar enlargement in paediatric liver transplant patients does not necessarily imply a diagnosis of PTLD. Furthermore, the presence of increased numbers of EBV infected cells in tonsils from liver transplant recipients by itself does not indicate an increased risk of developing PTLD.

[beta-Catenin induces invasive growth by activating matrix metalloproteinases in colorectal carcinoma]

beta-catenin was shown to be a major oncoprotein in colon cancer development. Its oncogenic function as a transcriptional activator is upregulated by mutations in the APC tumor suppressor gene, leading to a constitutive activation of the proliferation-associated genes c-myc and cyclin D. The aim of this study was to demonstrate a role of APC-mutations and dysregulated beta-catenin also for the progression of colorectal cancer, by identifying new target genes of beta-catenin associated with tumor invasion and metastasis. Potential invasion genes regulated by beta-catenin and its DNA binding partner TCF4 were identified by a computer search for the consensus DNA binding sequence in relevant promoter regions. Specific DNA binding was confirmed by gel shift assays. Functional importance of beta-catenin for the activation of identified genes was determined by luciferase reporter assays. The significance was demonstrated by coexpression of nuclear beta-catenin and the identified target genes by immunohistochemistry. Among other invasion genes, we identified the matrix metallo proteinases MMP-7 and MMP-1 activated by beta-catenin in the tumor cells. MMP-7 is an important factor for invasion and metastasis and overexpressed in 75% of colon carcinomas. The significance for human colon cancer development was demonstrated by a correlated overexpression of beta-catenin and the MMPs, beginning in large, severely dysplastic adenomas. Our results explain the high percentage of MMP-7 overexpression in colorectal tumors and the resulting activation of invasive growth. Moreover by identifying dysregulated beta-catenin as a transcriptional activator of MMPs and other invasion factors, we demonstrated an important role of mutated APC not only for early steps but also for the progression of colorectal carcinogenesis.

[Ultrasonographic examination in urinary tract infections]

The authors discuss the results ultrasonographic examination in children with urinary tract infections. The study included 435 children in aged 1 months-18 years treated in our Department since 1995 until 2000 y. In 260 (59.8%) children in USG examination changes in kidney were not observed. In 175 (40.2%) children changes in kidney were found.

Improvement of semen quality by nocturnal scrotal cooling and moderate behavioural change to reduce genital heat stress in men with oligoasthenoteratozoospermia

A questionnaire assessing factors that might cause an increase in scrotal temperature was completed by patients with reproducible oligoasthenoteratozoospermia of idiopathic nature or caused by varicocele. Evaluation by means of a grading scale revealed increased scrotal heat stress in oligoasthenoteratozoospermic patients compared with normozoospermic men (P < 0.01). In addition, long-term determination of 24 h scrotal temperature profiles showed that compared with semen donors, oligoasthenoteratozoospermic patients frequently had scrotal temperatures above 35.5 degrees C despite the same environmental temperatures (P < 0.05). In 88% of cases, maximum scrotal temperatures were measured during rest or sleep phases, whereas minimum values were recorded during physical activity or frequent change of position. Nocturnal scrotal cooling by means of an air stream resulted in a decrease in scrotal temperature of approximately 1 degrees C. Furthermore, a highly significant increase in sperm concentration (P < 0.0001) and total sperm output (P < 0.0001) was achieved after nocturnal scrotal cooling for 12 weeks together with a moderate decrease in factors leading to genital heat stress. A significant improvement in sperm motility (P < 0.05) and sperm morphology (P < 0.05) was also observed, but this improvement was markedly less pronounced than the changes in sperm concentration. This study shows the importance of genital heat stress as a cofactor in fertility impairment in men and indicates nocturnal scrotal cooling as a therapeutic option.

[Reasons for urinary tract infections in children based on personal observations]

The aim of this study was to analyse, basing on clinical observation, the reasons of urinary tract infection in children. The study included 1016 children with urinary tract infection /832 girls and 184 boys/ in the age between 2 weeks and 18 years old hospitalised in our Department in the period 1994-2000. The most common reasons of urinary tract infections were urinary tract abnormalities and the first among them was vesicoureteral reflux. In bacterial etiology Escherichia coli was the most common bacterial strain.

ANT1, an aromatic and neutral amino acid transporter in Arabidopsis

A new amino acid transporter was identified from the Arabidopsis expressed sequence tag cDNAs by expressing the cDNA in a yeast amino acid transport mutant. Transport analysis of the expressed protein in yeast showed that it transports aromatic and neutral amino acids, as well as arginine. This transporter (ANT1, aromatic and neutral transporter) also transports indole-3-acetic acid and 2,4-dichlorophenoxyacetic acid. The cDNA is 1.6 kb in length with an open reading frame that codes for a protein with 432 amino acids and a calculated molecular mass of 50 kD. Hydropathy analysis showed ANT1 is an integral membrane protein with 11 putative membrane-spanning domains. Southern analysis and a BLAST search of the Arabidopsis genome database suggests that ANT1 is part of a small gene family containing at least five members. Phylogenetic comparisons with other known amino acid transporters in plants suggests that ANT1 represents a new class of amino acid transporter. RNA gel-blot analysis showed that this transporter is expressed in all organs with highest abundance in flowers and cauline leaves.

Tip60 is a cell-type-specific transcriptional regulator

Tip60 was originally identified as cellular HIV-Tat interacting protein and has been shown to augment Tat-dependent transcription. It has also been shown to interact with various cellular transcription factors and to belong to the nuclear histone acetyltransferase (HAT) family. To further elucidate the function of Tip60 and its HAT domain in transcription regulation, we compared Tip60 activity in HeLa and Jurkat T lymphoma cells. Here we show that Tip60 augments the HIV-1 Tat activity at the HIV-LTR promoter in HeLa but inhibits it in Jurkat cells. Moreover, we isolated two new variants of the Tip60 protein (Tip60Delta1, Tip60Delta2) from Jurkat cells. The Tip60Delta2 variant lacks the entire HAT domain but modulates HIV-1 Tat activity like full-length Tip60. In addition, Tip60 and the transcriptional repressor ZEB (zinc finger E box binding protein) interact specifically in the yeast two-hybrid system and additively inhibit the CD4 enhancer/promoter activity in Jurkat cells. Thus, Tip60 may function as corepressor of the ZEB protein. In summary, these data show that Tip60 functions as a cell-type-specific transcriptional regulator and that the HAT domain is not required for either transcriptional activation or inhibition. This indicates that Tip60 may function by recruiting additional cell-type-specific cofactors.

Expression of the recombination activating genes (RAG1 and RAG2) is not detectable in Epstein-Barr virus-associated human lymphomas

The expression of the recombination activating genes (RAG1 and RAG2) is largely restricted to immature lymphoid cells. Previous studies have suggested that Epstein-Barr virus (EBV) infection may lead to a re-induction of RAG expression in mature B lymphocytes. To assess the significance of this mechanism for the pathogenesis of malignant lymphomas, we have examined the expression of RAG genes in 11 cases of EBV-associated endemic Burkitt's lymphoma (BL), 25 cases of Hodgkin's disease (HD, 17 EBV(+), 8 EBV(-)) and 10 cases of follicular non-Hodgkin's lymphoma (NHL). Using in situ hybridization, expression of the RAGs was detected in cortical thymocytes in normal thymus and in the tumor cells of 2 of 3 lymphoblastic NHL. By contrast, there was no detectable RAG expression in the BL, HD and follicular NHL cases. Our results indicate that re-induction of RAG expression does not occur in human lymphomas in vivo. Thus, it is unlikely to play a role in the development of translocations involving immunoglobulin gene loci which are characteristically found in BL and follicular NHL. Moreover, our study shows that in situ hybridization is a suitable method for the analysis of RAG expression in human tissue sections.

Fatal atypical T-cell proliferation associated with Epstein-Barr virus infection

We report the case of a young Caucasian man who presented with polyneuropathy and severe, ultimately fatal, congestive heart failure in the context of a chronic active Epstein-Barr virus (EBV) infection. Post-mortem examination revealed both monoclonal and polyclonal proliferation of EBV-positive atypical T lymphocytes within different organs. Predominant infiltration of the nervous system and heart with extensive myocardial scarring accounted for the clinical symptoms. The remarkable features of this case are (i) the occurrence in a Caucasian patient, (ii) the absence of detectable immunodeficiency, and (iii) the myocardial destruction by EBV-infected monoclonal T cells.

Cardiogenic embolism as the main cause of ischemic stroke in a city hospital: an interdisciplinary study

BACKGROUND

It is essential to understand the pathogenesis of ischemic stroke to ensure rational acute therapy and secondary prevention. We wanted to know the distribution of pathogenesis in patients of a city hospital and the differences in risk factors, neurologic deficits, disability, and delay in clinical admittance.

PATIENTS AND METHODS

During a period of one year, 222 patients (mean age 76.6 years; 59% women) with complete acute ischemic stroke were admitted and underwent complete clinical and diagnostic procedures: CCT/MRI; Doppler- and color-coded duplex and transcranial sonography; echocardiography; use of the NINCDS stroke scale and the Oxford disability scale; study of risk factors, and exploration of delay in admittance.

RESULTS

The following percentages of etiologies were evident: 31% cardiogenic embolism (60% with atrial fibrillation), 13% microangiopathy, 9% macroangiopathy, 11% cerebellar or brain stem infarction, 18% more than one cause and 18% no cause found. The patients with cardiogenic embolism showed significantly the highest scores on the stroke scale and the disability scale and had the shortest delay in admittance (57% were admitted within 3 hours).

CONCLUSIONS

In a city hospital, cardiogenic embolism is the main cause of ischemic stroke. These patients suffer significantly the most severe neurologic deficits, dependence, and requirement of daily nursing care. These patients have the shortest delay in clinical admittance and the best chance of benefitting from acute therapy and early secondary prevention.

Efficacy of surgical measures in preventing port-site recurrences in a porcine model

BACKGROUND

Port-site recurrences are serious complications of laparoscopy performed for cancer. Incidences reported in the literature vary between 0% and 21%, suggesting an influence of the surgeon.

METHODS

The aim of this experimental, prospective, randomized, single-blind study was to investigate the influence that the quality surgery has on the incidence of port-site recurrences. After a 12-mmHg carbon dioxide (CO2) pneumoperitoneum was created, 10(7) human HeLa cell were injected into the peritoneal cavity of 18 pigs, creating a xenogeneic tumor. Laparoscopic sigmoid resections then were performed using four trocars and a transanal double-stapling technique. The following protective measures were applied in nine animals: trocar fixation, prevention of gas leaks, rinsing of instruments with povidone-iodine, minilaparotomy protection, rinsing of trocars before removal, peritoneal closure, and rinsing of all wounds with povidoneiodine. Surgeons and type of procedures were randomized. After 4 weeks, the animals were killed and all portsites excised. Blinded immunohistologic analysis with antihuman pancytokeratin antibody was performed.

RESULTS

Tumor recurrence was present in 23 of 36 port sites (63.8%) in the control group, but only in 5 of 36 port sites (13.8%) in the group that received protective measures (p = 0.002; Fisher's exact test). No peritoneal carcinosis nor anastomotic recurrences were observed.

CONCLUSION

These results strongly suggest that the quality of surgical technique has an influence on the incidence of port-site recurrences. From now on, we propose to use these protective measures routinely in cancer laparoscopy.

[Infantile botulism caused by honey]

We report a case of a 5-week-old infant admitted with respiratory arrest. He had been fed with honey for two weeks. Infant botulism was suspected and confirmed by the finding of Clostridium botulinum toxin in the serum and faeces, and in the honey. The infant needed 7.5 months of ventilatory support.

Mismatch repair deficiency in sporadic synchronous colorectal cancer

BACKGROUND

Hereditary non-polyposis colorectal cancer (HNPCC) patients frequently develop synchronous colorectal cancer (SCRC) which also occurs sporadically in other patients. Recent studies on microsatellite instability (MSI) in sporadic SCRC diverge completely in their findings (0%-100%). In the present study MSI and mismatch repair (MMR) proteins were evaluated according to standardised criteria (exclusion of a family history, MSI analysed according to NCI recommendations)

METHODS

Paraffin embedded sections of SCRC of 30 patients were evaluated for MSI and the loss of protein expression of hMLH1 and hMSH2.

RESULTS

3 out of 30 (10%) patients exhibited MSI-H which 5 out of 30 (17%) showed MSI-L. Loss of protein expression of either hMLH1 or hMSH2 was found in all cases of MSI-H and none of the MSI-L cancers.

CONCLUSION

MSI is found in sporadic cases of SCRC to about the same extent as it is mentioned in the literature on sporadic single colorectal cancers. Immunohistochemistry with mismatch repair proteins could be used as a pre-screening for MMR deficiency in sporadic SCRC.

[Ischemic cerebral apoplexy in children]

During two years we identified eight children aged 1.5-10 years with cerebral ischaemic stroke. Prior to the stroke seven of eight children were in full health. Predisposing factors were endocarditis and trauma. Four children had prodomal symptoms prior to the infarction. All had acute hemiparesis on admission. Three of the children had fever, and five had varicellazoster infection three to 18 months prior to the stroke. Three children had convulsions. Seven of eight children had stenoses or occlusions of the middle cerebral or the basilar artery. Five children have persistent deficits and none have died. The children did not have coagulopathies, hypertension or arteriosclerosis. Echocardiography did not show patent foramen ovale. Early clinical and neuroradiological investigations are of importance in reaching the appropriate diagnosis.

[Male infertility. Current life style could be responsible for infertility]

Optimal spermatogenesis requires the testicles to be at a lower temperature than the body core. This is achieved by the following factors:--Blood in the testicular artery is precooled by the surrounding veins of the plexus pampiniformis; nevertheless, high fever results in substantial warming of the testicles;--Heat loss via the scrotal skin, with tight-fitting, thermally insulating clothing or obesity having an unfavorable effect;--increased circulation of air around the genitals on physical activity;--High temperature gradient to the environment when ambient temperatures are low. If the combination of these factors is unfavorable, disturbed spermatogenesis and fertility may result, which, however, is usually reversible. Likewise, electromagnetic waves may impair spermatogenesis by heat induction in the testicles, but only when exposure is excessive.

[Analysis of erythrocyturia causes in children]

The aim of this study was to assess, on the basing on clinical observation, the causes of erythrocyturia in children. The study include 438 children (214 girls and 224 boys) between 6 month and 17-teen years old with erythrocyturia, treated in Pediatric Nephrology Department from September 1992 till October 1999. The most common was the group of children with urolithiasis--162 (36.99%) and preurolithiasis state--126 (28.77%). In 153 cases urolithiasis was the only reason of erythrocyturia and in 9 children near urolithiasis the other reason (vesicouretheral reflux, urinary tract infection, glomerulitis, polycystic kidney) has been found. In 103 children the preulithiasis state was the only cause of erythrocyturia, in 23 children it was coexisted with others (vesicouretheral reflux, urinary tract infection, glomerulitis). As the more rare common causes were established vesicouretheral reflux, urinary tract infection, glomerulonephritis, in 36 children (8%) we did not find the reason of erythrocyturia. Variety of the reasons makes differential diagnostics of erythrocyturia complicated and needs experience and specialistic diagnostic investigation.

[Prevention of influenza--current recommendations]

Recommendation of the control of influenza include principal changes as follow: the age for universal vaccination has been lowered to 50 years from 65 years scheduling of large, organized vaccination campaigns after mid-October--2000/2001 trivalent vaccine virus strains are A/Moscow/10/99 (H3N2)-like, A/New Caledonia/20/99 (H1N1)-like, and B/Beijing/184/93-like strains.

[The effect of treatment methods on frequency of relapse in nephrotic syndrome in children]

The purpose of the work was to evaluate the influence of the treatment method in nephrotic syndrome on remission time and frequency of sickness relapse. Assessments were made in 26 children aged 1-17 years hospitalised in the Pediatric and Nephrology Department of the Military School of Medicine from 1993-1999. All children were steroid-sensitive, but only one patient didn't have relapse during the 3-years of observation. Because the most of children had oedema syndrome (92.3%) the treatment was started with intravenous hydrocortisone and continued with oral prednisone according to International Study of Kidney Disease in Children (ISKDC) criteria. 10 children with steroid-dependent syndrome were treated with intravenous methylprednisolone. Levamisole was given to 7 patients with concomitant respiratory infection. 7 other children were qualified for chlorambucil treatment. Choice of the treatment method in steroid-dependent and frequently relapsing nephrotic syndrome should be concordant with specificity of the particular patient's disease.

Mitochondrial oxidative phosphorylation is a downstream regulator of nitric oxide effects on chondrocyte matrix synthesis and mineralization

OBJECTIVE

Increased chondrocyte nitric oxide (NO) and peroxynitrite production appears to modulate decreased matrix synthesis and increased mineralization in osteoarthritis (OA). Because NO inhibits mitochondrial respiration, this study was undertaken to directly assess the potential role of chondrocyte mitochondrial oxidative phosphorylation (OXPHOS) in matrix synthesis and mineralization.

METHODS

We studied cultured human articular chondrocytes and immortalized costal chondrocytes (TC28 cells). We also assessed the effects of antimycin A and oligomycin (inhibitors of mitochondrial complexes III and V, respectively) on chondrocyte mitochondrial respiration, ATP synthesis, and inorganic pyrophosphate (PPi) generation, and the mineralizing potential of released matrix vesicles (MV).

RESULTS

Articular chondrocytes and TC28 cells respired at comparable rates. Peroxynitrite and NO donors markedly suppressed respiration and ATP generation in chondrocytes. Because NO exerts multiple effects on chondrocytes, we investigated the primary functions of mitochondrial respiration and OXPHOS. To do so, we identified minimally cytotoxic doses of antimycin and oligomycin, which both induced intracellular ATP depletion (by 50-80%), attenuated collagen and proteoglycan synthesis, and blocked transforming growth factor beta from increasing intracellular ATP and elaboration of PPi, a critical inhibitor of hydroxyapatite deposition. Antimycin and oligomycin also abrogated the ability of the ATP-hydrolyzing enzyme plasma cell membrane glycoprotein 1 (PC-1) to increase chondrocyte PPi generation. Finally, MV from cells treated with antimycin or oligomycin contained less PPi and precipitated >50% more 45Ca.

CONCLUSION

Chondrocyte mitochondrial reserve, as NO-sensitive mitochondrial respiration-mediated ATP production, appears to support matrix synthesis and PPi elaboration and to regulate MV composition and mineralizing activity. NO-induced depression of chondrocyte respiration could modulate matrix loss and secondary cartilage mineralization in OA.

Enhanced replication contributes to enrichment of hepatitis B virus with a deletion in the core gene

Accumulation in immunosuppressed patients of hepatitis B virus (HBV) with a deletion in the C gene is associated with severe liver disease. The aim of this study was to determine the phenotype of such genomes in vitro. Four C gene fragments with different types of deletions were inserted in the context of a wild-type genome and tested by transfection into HuH7 cells. The deletions did not influence mRNA and surface protein levels. Truncated C gene translation products were expressed only from variants with in-frame deletions, whereas full-length polymerase was expressed from all variants at a similar or higher level than in wild-type virus. None of the variants was competent for autonomous replication; however, they produced 2- to 4.5-fold more progeny DNA than wild-type HBV when sufficiently complemented with wild-type core protein. Similarly, when variant and wild-type DNA were cotransfected in different ratios, the variants produced 2- to 5-fold more progeny DNA relative to the wild-type; this enrichment required the expression of the viral polymerase in cis. The mechanism of enrichment depended on the percentage of variant in the transfected DNA mixture. When the transfected DNA contained a small percentage of variant, enhanced replication of the variant accompanied by no or little suppression of wild-type replication was seen. Accordingly, overall production of progeny virus was slightly increased. At a high percentage of variant DNA, replication of both variant and wild-type decreased, probably due to a shortage of wild-type core protein. In conclusion, emergence of C gene deletion variants in vivo may be due to enhanced replication mediated at the level of encapsidation or reverse transcription. If the variants constitute a small part of the ccc DNA, they can be fully trans-complemented by wild-type virus which may increase the overall virus production.

Microsatellite instability in colorectal adenomas: relevance and clinical importance

A number of investigations have recently been published on the role of microsatellite instability (MSI) in the process of colorectal carcinogenesis. The data concerning colorectal adenomas are difficult to compare (due to differences in the tumor collection, selection and number of analyzed loci, definition of high and low instability and histological types), and this review therefore examines the significance of the results of these publications. We then discuss the extent to which MSI and its effects on the integrity of the genome are early or late events in the malignant transformation, and which clinicopathological features are presented by MSI-positive adenomas. Finally, we consider the clinical importance of microsatellite status for the diagnosis of hereditary nonpolyposis colorectal cancer and the possibility of preventing adenomas and carcinomas by nonsteroidal anti-inflammatory drugs.

Mitochondrial oxidative phosphorylation is a downstream regulator of nitric oxide effects on chondrocyte matrix synthesis and mineralization

OBJECTIVE

Increased chondrocyte nitric oxide (NO) and peroxynitrite production appears to modulate decreased matrix synthesis and increased mineralization in osteoarthritis (OA). Because NO inhibits mitochondrial respiration, this study was undertaken to directly assess the potential role of chondrocyte mitochondrial oxidative phosphorylation (OXPHOS) in matrix synthesis and mineralization.

METHODS

We studied cultured human articular chondrocytes and immortalized costal chondrocytes (TC28 cells). We also assessed the effects of antimycin A and oligomycin (inhibitors of mitochondrial complexes III and V, respectively) on chondrocyte mitochondrial respiration, ATP synthesis, and inorganic pyrophosphate (PPi) generation, and the mineralizing potential of released matrix vesicles (MV).

RESULTS

Articular chondrocytes and TC28 cells respired at comparable rates. Peroxynitrite and NO donors markedly suppressed respiration and ATP generation in chondrocytes. Because NO exerts multiple effects on chondrocytes, we investigated the primary functions of mitochondrial respiration and OXPHOS. To do so, we identified minimally cytotoxic doses of antimycin and oligomycin, which both induced intracellular ATP depletion (by 50-80%), attenuated collagen and proteoglycan synthesis, and blocked transforming growth factor beta from increasing intracellular ATP and elaboration of PPi, a critical inhibitor of hydroxyapatite deposition. Antimycin and oligomycin also abrogated the ability of the ATP-hydrolyzing enzyme plasma cell membrane glycoprotein 1 (PC-1) to increase chondrocyte PPi generation. Finally, MV from cells treated with antimycin or oligomycin contained less PPi and precipitated >50% more 45Ca.

CONCLUSION

Chondrocyte mitochondrial reserve, as NO-sensitive mitochondrial respiration-mediated ATP production, appears to support matrix synthesis and PPi elaboration and to regulate MV composition and mineralizing activity. NO-induced depression of chondrocyte respiration could modulate matrix loss and secondary cartilage mineralization in OA.

p27(kip1) expression in rectal cancer correlates with disease-free survival

BACKGROUND

The cell-cycle inhibitor p27(kip1) is a potential tumor suppressor and might serve as a prognostic marker in rectal cancer, in particular with regard to patient selection for adjuvant therapy.

MATERIALS AND METHODS

Immunohistochemical analysis was performed, using an anti-p27(kip1) monoclonal antibody, on paraffin sections of two matched [age, gender, UICC stage, year of operation (1982-1991)] groups of patients (n = 2 x 82) with rectal carcinoma curatively treated by surgery alone. The groups differed only in subsequent metachronous distant metastatic spread. All patients had to meet the selection criterion "free of local disease," in order to exclude surgical influence. Follow-up was prospective (median of 74 months). The intensity of staining (-, +, ++, ) and rate of positive cells (as a percentage of total tumor volume) were judged separately for cytoplasms and nuclei.

RESULTS

On multivariate analysis, cytoplasmic staining intensity proved to be the best prognostic factor of disease-free survival and approached statistical significance (P = 0.0552, Cox regression). On univariate analysis, considering cytoplasmic staining alone, intensely stained ( ) tumors showed significantly poorer disease-free survival (vs ++, +, -; Kaplan-Meier, logrank, P = 0.0185).

CONCLUSIONS

The demonstrated correlation between cytoplasmic compartmentalization of p27(kip1) and increased metastatic spread as well as disease-free survival underscores the role of p27(kip1) in rectal cancer. However, since other reports emphasize the importance of nuclear p27(kip1) expression, the mechanisms of steady-state and subcellular distribution of p27(kip1) remain unclear, and further investigation is needed.

Description of an intraperitoneal tumour xenograft survival model in the pig

AIMS

Experimental animal studies are necessary if the results of minimally invasive oncological surgery are to be improved. In particular the influence of surgical technique on tumour implantation needs further assessment. Small animals such as rodents are inappropriate for such laparoscopic surgical studies. There is a requirement for another animal tumour model with animals greater in size.

METHODS

Accordingly we developed an intraperitoneal tumour xenograft survival model using the domesticated pig. After creating a 12 mmHg pneumoperitoneum, 10(7)human HeLa cells were injected into the peritoneal cavity of nine non-syngeneic animals to induce tumour xenograft. Resection of the sigmoid colon using four trocars and a transanal double-stapling technique was performed. The mean operating time was 69 min. No signs of post-operative pain symptoms were observed, and all the animals survived the procedure and gained weight. After 4 weeks, the animals were sacrified and all incision sites and anastomoses were excised.

RESULTS

Immunohistochemical staining with antihuman pancytokeratin antibodies confirmed tumour implants in 25 out of 36 port-sites (63.8%). No peritoneal carcinosis nor tumour implants at anastomosis sites were observed.

CONCLUSION

This intraperitoneal xenograft tumour model in the pig can be applied in survival studies to check the quality of surgical techniques and its influence on tumour implantation following laparoscopy for cancer.

[Results of the treatment of pre-urolithiasis state in children with recurrent urinary tract infections]

Urolithiasis often coexists with recurrent urinary tract infections (RUTI). The aim of the study was to determine the correlation of preurolithiasis state (PS) and recurrent urinary tract infections and to establish an effect of the treatment UTI recurrence incidence. PS was found in 202(21.1%) children, most frequently: hyperoxaluria--in 61/202 (30.2%), hypercalciuria--in 32/202 (15.8%), and hyperuricosuria--in 30/202 (14.9%) children. Complex metabolic abnormality was observed in 62/202 (30.7%) patients. Therapeutic management comprised of: antibacterial prophylaxis, high fluid intake, proper diet, correction of urine pH, and pharmacological treatment if necessary. Disappearance of RUTI and PS in 88/202 (43.6%) children, disappearance of RUTI in spite of persistent PS in 36/202 (17.8%), and decrease of RUTI in 54/202 (26.7%) patients were method. In 110/202 (54.5) children PS disappeared.

[Results of ESWL treatment in children with urolithiasis: own experience]

Actually extracorporeal shock wave lithotripsy (ESWL) is the most frequent method in the treatment of urolithiasis in children. The aim of the study was to estimate the results of ESWL in children with urolithiasis. Between 1991 and 1999 y, in our Department 260 "reno-ureteral units" in 203 children were treated by lithotripsy. Totally of 518 ESWL procedures were performed. In general efficacy of ESWL was 88.08%, in children with single stone in kidney--97.80%., with multiple stones in kidneys--78.65%, in ureterolithiasis--71.88%. For complete recovery in patients mean 1.99 ESWL procedures were performed on 1 "reno-ureteral unit" on the average diameter of the stone/stones 13.3 mm.

[Hypocitraturia in children with urolithiasis]

Inhibitors of crystallization process play an important role in renal-stone forming patients. One of well-known inhibitor is citrate. The aim of the study was to define the type of metabolic abnormality in children with nephrolithiasis and the role of urinary citrate excretion. 52 children with nephrolithiasis were examined. Hypocitraturia was observed in 42.3% of patients, most frequently in children with hypercalciuria, hyperoxaluria, and hyperoxaluria with hyperuricosuria. Low urinary citrate excretion found in patients with nephrolithiasis may play an important role in the pathogenesis of the disease. Urinary citrate excretion should be examined in patients with nephrolithiasis.

[A form of premorbid condition of urolithiasis and urinary stone composition in children with urolithiasis]

In diagnosis, monitoring and prophylaxis of urolithiasis it is important to use simple, non-invasive tests. The aim of the study was to define the value of crystallizing ratios in urine in correlation with chemical stone composition in presumptive diagnosis and monitoring patients with urolithiasis. The study involved 102 children. An analysis of chemical stone composition was carried out in 62 cases. A correlation between values of crystallizing ratios in the urine, indicating the kind of preurolithiasis state and chemical stone composition has been found.

[Clinical assessment of Uro-Vaxom in the treatment and prophylaxis of recurrent urinary tract infection in children: preliminary results]

The aim of the study was to determine the efficiency of Uro-Vaxom in the treatment of recurrent urinary tract infection in children. We examined 19 girls in aged 4-17 years treated in our Department since Jan 1998 until Jan 1999 for of recurrent urinary tract infection induced by E. coli (RUTI). All girls have been cured with Uro-Vaxom in single daily dose for 3 months. Disappearance of RUTI in 47% of children and decrease in RUTI in 42% reveals that Uro-Vaxom plays significant role in the treatment of this disease.

[The role of environmental factors in the formation of kidney calculi]

Various endo- and exogenous factors play a role in the urinary stones formation tract. The aim of the study was to define the type and frequency of hyperexcretion of lithogenic substances in school children population and to determine an influence of risk factors on hyperexcretion of crystallizing substances. The study included 220 school children. Preurolithiasis state (PS) was found in 30% children. The most frequently hyperoxaluria, hyperuricosuria and hypercalciuria were diagnosed and it may be connected with abnormal nutritional habits, excessive application of multivitamins, vitamin D and calcium, disturbances in drinking water chemical composition (higher amount of calcium, smaller amount of magnesium, abnormal pH). Urinary tract infections, particularly in children with obstructive uropathy are an important risk factor in the examined population. Positive familial history of urolithiasis in 43.3% children may indicate for the important role of the genetic factor in the pathogenesis of the disease.

[Specificity of uroflowmetry as a screening test for the urinary tract diseases in children]

The aim of the study was to determine the specificity of uroflowmetry a screening testing the urinary diseases in children. We have investigated 70 children. Patients were divided in 3 groups. Group I included 38 children with recurrent urinary tract infections, group II included 18 children with enuresis, and group III included 14 children with preurolithiasis state. Pathological uroflowmetry was detected in 11 children (15.7%), which indicating the need of using this test during diagnostic process.

[Nephrolithiasis: a new approach to the old disease]

The epidemiology and metabolic causes of the nephrolithiasis may be different. The author discusses, in a very selective way, major advances in the understanding of this disease.

[Etiology of nephrolithiasis in children: own observation]

Recurrent formation of renal calculi may be prevented by selective medical therapy designed to correct underlying metabolic disturbances in urine biochemistry. The aim of the study was to estimate potential risk factors of urolithiasis in 102 children before ESWL treatment. Metabolic disturbances followed by anatomical malformations of urinary tract, recurrent urinary tract infections caused by urease-induced microorganisms are the most frequent risk factors. In single cases possible risk factors were: immobilization and chronic corticosteroid therapy.

[Changes of kidney parenchyma in children with nephrolithiasis after ESWL treatment in ultrasonography, power Doppler and thermovision monitoring]

The authors discuss the results ultrasonographic (USG), power Doppler (PD) and thermovision (TV) examination in monitoring changes of kidney parenchyma in 30 children with nephrolithiasis after ESWL treatment. To monitor possible effect of shock wave on the kidney parenchyma the USG, PD and TV examination were done before ESWL treatment as well as, 48 hours and 3 months following the treatment. Parts of kidney parenchyma localized on the way of shock wave to the stone were analysed. Echogenicity of kidney parenchyma was analysed by comparison of echo amplitude in subsequent USG examinations. Parenchymal blood flow by computer analyse was estimated. In TV examination the temperature distribution in the place of skin kidney projection was estimated. Changes in echogenicity of kidney parenchyma and impaired kidney parenchymal blood flow 48 hours after ESWL were found. In TV examination 48 hours after ESWL transient reduction in skin temperature was observed in the place of shock wave transmission. In 3 months after ESWL disturbances in the kidney parenchyma in USG, PD and TV were not observed.

[Beta-2 microglobulinuria in children with vesico-ureteral reflux and recurrent urinary tract infections]

Recurrent urinary tract infections in children with vesico-ureteral reflux are the one of risk factors in the process of reflux nephropathy. One of markers of early kidney parenchyma damage is beta 2-microglobulin. The aim of the study was to evaluate the value of beta 2-microglobulin excretion in urine and its serum levels in children with vesico-ureteral reflux and recurrent urinary tract infections. It was found that abnormal urinary excretion of beta 2-microglobulin and its serum levels of proceeded post-inflammatory changes in kidney parenchyma observed in imaging examinations of urinary tract and impared parameters of renal function in biochemical analyses.

Expression of nuclear beta-catenin and c-myc is correlated with tumor size but not with proliferative activity of colorectal adenomas

Most colorectal cancers have loss-of-function mutations in the adenomatosis polyposis coli (APC) tumor suppressor gene. This leads to the accumulation of nuclear beta-catenin, which, together with the DNA-binding protein TCF-4, functions as a transcriptional activator. The recently defined target genes c-myc, cyclin D1, and matrilysin are responsible for tumor proliferation or malignant progression and explain the oncogenic potential of nuclear beta-catenin. To investigate its role in early colon carcinogenesis, we analyzed the expression of beta-catenin, its target gene c-myc, and the proliferative activity in 88 colorectal adenomas of varying size and grade of dysplasia. The results revealed i) the most significant correlation of nuclear beta-catenin and c-myc expression was not with the grade of dysplasia but with the size of the colon adenoma; ii) perfect correlation of nuclear beta-catenin and c-myc expression; iii) no significant correlation of adenoma size with the proliferative activity; and iv) no significant correlation of proliferative activity and the nuclear expression of beta-catenin and c-myc. These results imply that APC mutations have additional beta-catenin-independent functions; APC mutations alone are not sufficient for nuclear overexpression of beta-catenin; and nuclear beta-catenin has additional important functions for exceeding a threshold tumor size.

Imported lassa fever in Germany: molecular characterization of a new lassa virus strain

We describe the isolation and characterization of a new Lassa virus strain imported into Germany by a traveler who had visited Ghana, Côte D'Ivoire, and Burkina Faso. This strain, designated "AV," originated from a region in West Africa where Lassa fever has not been reported. Viral S RNA isolated from the patient's serum was amplified and sequenced. A long-range reverse transcription polymerase chain reaction allowed amplification of the full-length (3.4 kb) S RNA. The coding sequences of strain AV differed from those of all known Lassa prototype strains (Josiah, Nigeria, and LP) by approximately 20%, mainly at third codon positions. Phylogenetically, strain AV appears to be most closely related to strain Josiah from Sierra Leone. Lassa viruses comprise a group of genetically highly diverse strains, which has implications for vaccine development. The new method for full-length S RNA amplification may facilitate identification and molecular analysis of new arenaviruses or arenavirus strains.

Unexplained fever-analysis of 233 cases in a referral hospital

A study was conducted to analyse the causes of fever of unknown origin (FUO) in a teaching hospital in central India. Study subjects consisted of 233 patients having FUO admitted in the medical ward. Specific causes of FUO were identified in 73.4% cases. The commonest causes (46.4%) were of infectious diseases origin foremost being enteric fever (29.6%) followed by malaria (9.0%) and tuberculous fever (5.2%). Chloroquine responsive fever accounted for 26% cases of FUO. Enteric fever were seen more commonly in younger adults less than 50 years, tuberculous fever presented usually after four weeks of onset of symptoms and more in elderly patients aged 50 years or more. Intermittent type of fever was more commonly recorded in infectious diseases. Approach to causes of FUO should be focused primarily on infectious diseases followed by other specific investigations. Empirical treatment of cases having intermittent fever with chloroquine seems justifiable even in absence of malarial parasite in peripheral blood smear.

beta-catenin regulates the expression of the matrix metalloproteinase-7 in human colorectal cancer

Most colorectal cancers have loss of function mutations in the adenomatosis polyposis coli (APC) tumor suppressor gene. This leads to accumulation of beta-catenin, which together with the DNA binding protein TCF-4 functions as a transcriptional activator. Recently defined target genes are c-myc and cyclin D1, linking the APC gene defect to the capacity for autonomous proliferation of colon tumors. Here we report the identification of the matrix metalloproteinase MMP-7 as another target gene of beta-catenin/TCF-4. MMP-7 is overexpressed in 80% of human colorectal cancers and known to be an important factor for early tumor growth, with a potential function also for later progression steps, like invasion and metastasis. Our results explain the high percentage of MMP-7 overexpression in colon tumors. Moreover they indicate that defects in the APC tumor suppressor gene may also have an influence on later steps of colon tumor progression.

Negative regulation of CD4 expression in T cells by the transcriptional repressor ZEB

ZEB, an E-box binding transcriptional repressor, is an important regulator of T cell and muscle development. Targeted disruption of ZEB in mice resulted in a strong reduction of thymocytes and the few T cells that reached the mature stage were predominantly CD4(+). CD4 expression during the various stages of T cell differentiation is controlled at the transcriptional level by a complex array of regulatory elements in the CD4 gene locus, consisting of at least three enhancers, one promoter and one silencer. Here we present evidence that CD4 gene expression is negatively regulated by ZEB. We show that ZEB binds to the 5'E-box in the CD4-3 element of the proximal CD4 enhancer in competition with the transcriptional activators E12 and HEB, thereby reducing CD4 expression on CD4 single-positive but not CD4/CD8 double-positive T cells. The conversion of the CD4 proximal enhancer into a potential silencer element by the transcriptional repressor ZEB offers an additional concept of CD4 gene regulation in T cells.

[Resection and replacement of the cervical esophagus and hypopharynx--an interdisciplinary responsibility for visceral, micro- and ENT surgeons]

From 1984 to 1996, 136 carcinomas of the esophagus and 8 of the hypopharynx were resected using 3 different procedures (94 transmediastinal, 36 transthoracic, 14 cervicoabdominal). The hospital mortality rate for cervicoabdominal resection (0%) is unequivocally lower than that of the transmediastinal (17.1%) or transthoracic (14.3%) methods. The 5-year survival rates are not significantly different (24%, 22%, 17%).

Nuclear overexpression of the oncoprotein beta-catenin in colorectal cancer is localized predominantly at the invasion front

Sixty to eighty percent of all colorectal cancers are characterized by mutations in the APC tumor suppressor gene. Recently, it was shown that these mutations lead to a nuclear overexpression of beta-Catenin by disruption of the wingless/WNT signal pathway. Since nuclear beta-Catenin functions as a transcriptional activator of hitherto unknown tumor genes, this form of beta-Catenin is now considered a major oncoprotein in colorectal cancer. Using immunohistochemistry, we investigated the distribution of overexpressed beta-Catenin within individual colorectal carcinomas. In the majority of the tumors, we found no homogeneous staining, but a strong nuclear expression of beta-Catenin predominantly localized at the invasion front with strongest nuclear staining of isolated, scattered tumor cells. In contrast, cells in the tumor center often showed no nuclear staining, but retained a membranous expression of beta-Catenin, comparable to normal colon epithelium. It is, therefore, likely that in addition to the overexpression of beta-Catenin caused by defects in the APC locus, regulatory events in the tumor itself lead to a different distribution of this oncoprotein. Possibly, surrounding tissue at the invasion front can give signals to the tumor cells, leading to a nuclear translocation of beta-Catenin, where it may play a direct role in tumor invasion processes.

Predictive value of nuclear beta-catenin expression for the occurrence of distant metastases in rectal cancer

PURPOSE

Adenomatous polyposis coli protein, glycogen synthetase kinase-3-beta, T cell transcription factor/lymphoid enhancer-binding factor, and beta-catenin modulate cell differentiation and proliferation via the expression of effector genes. It has recently been postulated that beta-catenin is a potent oncogene of sporadic colorectal carcinogenesis and a prognostic tumor marker. Our aim was to investigate whether the nuclear overexpression of beta-catenin, possibly caused by mutations in exon 3 of beta-catenin (CTNNB1), is correlated with distant metastatic spread or disease-free survival in rectal carcinoma.

METHODS

Immunohistochemical analysis was performed with an anti-beta-catenin-monoclonal antibody on paraffin sections of two groups of patients (n = 2 x 77) with rectal carcinoma curatively treated by surgery alone. The patients selected were all free of local disease, to exclude surgical influence. Patient groups were matched for age, gender, International Union Against Cancer stage, and year of operation (1982 to 1991) and differed only in subsequent metachronous distant metastatic spread. Follow-up was prospective (median, 9.6 years). Three staining patterns were defined: membranous (normal), diffuse cytoplasmic (pathologic), and intense nuclear staining (pathologic). When intense nuclear staining was defined, the specimen was microdissected. Then, DNA was isolated, polymerase chain reaction-amplified, and sequenced to detect mutations in exon 3.

RESULTS

Nuclear overexpression of beta-catenin correlated neither with distant metastatic spread (chi-squared, 0.37; P = 0.79) nor with disease-free survival (log-rank with trend, P = 0.62). No mutations were found in the area of the serine/threonine-kinase glycogen synthetase kinase-3-beta-phosphorylation site in exon 3 (CTNNB1) of beta-catenin.

CONCLUSION

Although beta-catenin seems to play an important role in early colorectal carcinogenesis, its value as a prognostic marker is questionable. It must be assumed that metastatic ability is determined by other factors than the disturbance of the beta-catenin T cell transcription factor/lymphoid enhancer-binding factor cascade and that other mechanisms might cause the observed nuclear translocation of beta-catenin.