Sjögren's syndrome co-existing with limited Wegener's granulomatosis.
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Biomedical subjects
Publications and source records attributed to C Kittas.
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The two subtypes of corticosterone receptors in the rat brain play a pivotal role in the modulation of the stress response. Appropriate control of their gene expression is therefore critical for the maintenance of cellular and organism homeostasis. In this study, we investigated the contribution of gender and of the cellular environment of certain brain areas to the expression of both types of corticosteroid receptors, following restraint stress. Adult Wistar rats of both sexes were subjected to acute, chronic or to a combined chronic plus acute stress regimen, and the expression of glucocorticoid and mineralocorticoid receptors was evaluated in their hippocampus, hypothalamus, pituitary and frontal cortex, by using Northern blot analysis. Significant sex differences were observed in the first three brain areas examined as to the stress-induced expression of corticosteroid receptors. Among these, females showed a distinct mechanism of regulating glucocorticoid/mineralocorticoid receptor ratio in the hippocampus upon chronic stress, while the female hypothalamus was more prone than the male to changing corticosteroid receptor expression in response to restraint stress. In another set of experiments, we assessed the influence of ovarian steroids on stress-induced corticosteroid receptor expression in the above brain areas by analyzing ovariectomized rats exposed to short-term restraint. Our results showed that although ovarian steroids affect the stress-induced expression of receptor genes in a region-specific manner, their elimination does not appear to lead to the male pattern of expression. These findings provide further evidence for the existence of both regional and gender specificity in the regulation of brain and pituitary corticosteroid receptors following stress, and support the hypothesis of a distinct male and female neuroendocrine axis in response to stress.
To evaluate the efficacy of EBVD combination chemotherapy followed by low dose (LD) involved field (IF) radiation therapy (RT) in patients with clinical stage (CS) I-IIA Hodgkin's disease (HD), we analyzed 148 patients treated in our Unit from March 1988 to November 1995. EBVD consisted of Epirubicine 40 mg/m2, Bleomycin 10 mg/m2, Vinblastine 6 mg/m2 and Dacarbazine 300 mg. All drugs were administered i.v. at days 1 and 15, every 4 weeks, for a total of 4-6 cycles. LDIF RT (24-32 Gy) was scheduled for patients with complete response (CR) or >90% reduction of tumor load, after EBVD. Patients with stable or progressive disease (SD, PD) after EBVDx3 or poor compliance to the regimen received mantle or inverted Y RT at standard dose. The median follow-up of patients currently alive was 71.5 months. 129 patients achieved a CR after EBVD and 10 a >90% reduction of tumor load, for a post-CT response rate of 94%. Eight patients had SD after EBVDx3 and one had a partial response with poor compliance. All 9 patients received mantle or inverted Y RT and 8/9 achieved a CR. Nine patients relapsed at a median of 7 months from the end of treatment. At 10 years, FFS was 90% and overall survival 95%. Six patients have died so far; 5 of HD and one of stroke. One patient developed a diffuse large cell lymphoma 48 months after the diagnosis of HD. We conclude that EBVD followed by LDIF RT is a highly effective regimen for patients with CS I-IIA HD. Longer follow up is required to assess the risk of secondary malignancies, especially solid tumors.
BACKGROUND: Recent in vitro studies provide evidence that the cell cycle molecules pRb, p53 and MDM2 form a tightly regulated protein network. In this study, we examined the relationship of this protein network in a series of non-small cell lung carcinomas (NSCLCs), with the kinetic parameters, including proliferative activity or proliferation index (PI) and apoptotic index (AI), and ploidy status of the tumors. MATERIAL AND METHODS: A total of 87 NSCLCs were examined using immunohistochemical and molecular methods in order to estimate the status of the pRb-p53-MDM2 network. The kinetic parameters and the ploidy status of the tumors were assessed by in situ assays. The possible associations between alterations of the network, kinetic parameters and ploidy status of the carcinomas were assessed with a series of statistical methods. RESULTS: Aberrant expression of pRb (Ab) and overexpression of p53 (P) and MDM2 (P) proteins were observed in 39%, 57%, and 68% of the carcinomas, respectively. The comprehensive analysis revealed that concurrent alterations in all three cell cycle regulatory molecules were the most frequent pattern, pRb(Ab)/p53(P)/MDM2(P); this "full abnormal" phenotype represented approximately 27% of the cases. This immunoprofile obtained the highest PI/AI value; whereas, the "normal" phenotype was the lowest one (p = 0.004). Furthermore, the pattern pRb(Ab)/p53(P)/MDM2(P) acquired the highest PI (p < 0.001) and lowest AI (p < 0.001) scores. Interestingly, the groups of carcinomas with impaired expression of one or two molecules attained PI/AI ratio values clustered in a narrow range placed in the middle of the scores exhibited by the "normal" and "full abnormal" phenotypes. These tumors had significantly lower AI, but similar PI values, compared with those noticed in the normal pattern. In addition, it was observed that the pRb(Ab)/p53(P)/MDM2(P) phenotype was also significantly associated with aneuploidy (p = 0.002) and a tendency was observed when the expression of two components was altered (p = 0.055). CONCLUSIONS: Our findings suggest that simultaneous deregulation of all members of the pRb-p53-MDM2 network confers an additive effect on tumor growth. The apoptotic pathway seems to be more susceptible to its defects than the cell proliferation machinery. The findings of the ploidy analysis, which are in parallel with those regarding the proliferative activity and the apoptotic rate study, further support the concept that these molecules constitute a tightly regulated network participating in cell cycle control and chromosomal stability.
Possible protective effects of two therapeutical agents (nimesulid and metoprolol) in adriamycin-induced cardiotoxicity were examined in rat cardiomyocytes at the mitochondrial DNA (mt DNA) level. Analysis by PCR revealed the presence of multiple deletions in a large region of the long arc of mt DNA which codes for several important genes involved in oxidative phosphorylation, in all animals under drug administration. No differences were found in the frequency of defective mt DNA between the animals that received only adriamycin (83%, 10/12), nimesulid and adriamycin (92%, 13/14), or metoprolol and adriamycin (80, 12/15) (p = 0.004).
Data on human papilloma virus (HPV) involvement in preneoplastic and neoplastic lesions of the larynx and lung are limited and conflicting. The presence of HPV was investigated in a series of laryngeal specimens and non-small cell lung carcinomas (NSCLCs). The laryngeal samples (154) comprised 14 cases with hyperplasia without dysplasia, 49 with dysplasia, and 91 squamous cell carcinomas (SqCCs). The NSCLCs included 31 SqCCs, 32 adenocarcinomas, and 5 undifferentiated large cell carcinomas. Furthermore, we examined, for HPV DNA sequences, 14 bronchial metaplastic squamous lesions located next to cancerous areas. We used a sensitive nested polymerase chain reaction assay (NPCR), dot blotting, and in situ hybridization. The findings were correlated with clinicopathologic features of the patients. In the laryngeal specimens, NPCR analysis showed HPV DNA in 20 (13%) of the 154 specimens. Notably, 19 of 20 HPV-positive cases were carcinomas and only one was a mild dysplastic lesion. Typing of the carcinomas showed single HPV 6, 16, 18, and 33 infection in 1 (1.1%), 12 (13.2%), 2 (2.2%), and 1 (1.1%) samples, respectively, and HPV 6/33, 16/33, and 6/18 coinfection in three carcinomas. In situ hybridization findings were in agreement with PCR results, with the exception of two cases in which HPV 18 DNA was detected only by PCR. HPV was more frequently observed in heavy smokers than in patients with low daily cigarette consumption and nonsmokers (P = .03). There was no correlation between virus infection and gender, grade, and lymph node status of the carcinomas. None of the NSCLCs or adjacent metaplastic squamous epithelium contained HPV DNA sequences. The presented data suggest a contributory role of HPV in late stages of laryngeal carcinogenesis, because all premalignant lesions were negative but one. This study does not support a potential role of HPV in the development of NSCLCs.
Cytogenetic analysis was performed in 60 patients with primary myelodysplastic syndromes--diagnosed, treated, and followed in our department. In 41 cases, the presence of the NRAS mutation was also evaluated. The aim of this study was to evaluate the prognostic value of chromosomal abnormalities and NRAS mutation. The median age of the patients was 67 years (18-88 years), and the French-American-British classification was as follows: refractory anemia 26, refractory anemia with ring sideroblasts 4, refractory anemia with excess of blast cells 15, refractory anemia with excess of blast cells in transformation 3, and chronic myelomonocytic leukemia 12. Survival analysis was performed for the patients with a normal (n = 35), an abnormal (n = 25) karyotype and with a single (n = 15) or multiple (n = 10) cytogenetic abnormalities. Abnormal karyotypes were detected in 25 of the 60 patients (41.6%). Fifteen of these patients had a single and 10 had two or more lesions. The median survival of the patients with a normal (33.1 months) and with an abnormal (36.5 months) karyotype was not significantly different. Patients with multiple lesions had a reduced median survival compared with patients with single anomalies (19.2 versus 39.7 months, p = 0.5). Patients with an abnormal karyotype progressed to acute leukemia more frequently compared with patients without lesions (36 versus 28.6%, p = 0.5). NRAS mutation was detected in 2 of 10 CMMoL patients studied and in none of the 31 patients with other types of myelodysplastic syndrome. Marrow blasts more than 10% significantly affected survival.
Angiolymphoid hyperplasia with eosinophilia (ALHE) is a benign uncommon entity whose aetiology and pathogenesis is under debate. Clinically, it is characterised by cutaneous papules or nodules. Cases of this entity reported in the oral mucosa are very rare. We describe such a case, discuss the problems of histological differential diagnosis between ALHE and other diseases of the region and review the literature.
Stressful stimuli are known to affect glucocorticoid receptor (GR) mRNA levels in the rat brain. The aim of this study was to examine the duration of chronic stress-induced changes in GR gene expression in the male rat hippocampus and cerebellum. By using in situ hybridization histochemistry, we detected a statistically significant down-regulation of GR mRNA both in the hippocampus and in the cerebellum of rats stressed for 8, 10 and 14 days. The same degree of down-regulation could also be detected in the above brain areas of rats stressed for 14 days and left undisturbed for 48 h or 8 days after stress. To examine the effects of subsequent stressors on the expression of down-regulated GR mRNA in the hippocampus of chronically stressed rats, we determined, by Northern blotting, GR mRNA levels in the hippocampi of rats stressed for 14 days and subsequently exposed to either short- or long-duration stressors. The down-regulated levels of GR mRNA remained practically unaffected when a subsequent new stressor was applied. Our results show that chronic stress-induced down-regulation of GR mRNA in the rat brain can be extended for periods longer than the initial/causative stimulus, irrespective of the presence of a novel stimulus.
Among small lymphocyte cell disorders, B-chronic lymphocytic leukemia (B-CLL), small lymphocytic lymphoma (SLL), and lymphoplasmacytic lymphoma/Waldenström's macroglobulinemia (LPL/MW) are included. B-CLL patients always have blood and bone marrow (BM) involvement by a CD5+ B lymphocyte. They frequently present with lymphadenopathy and/or hepatosplenomegaly, although in a considerable number of patients, no abnormal physical findings are found. They are prone to develop hypogammaglobulinemia, autoimmune hemolysis, or autoimmune thrombocytopenia. The typical immunophenotype of the malignant cell is CD5+, surface immunoglobulin (slg)+ (weak), CD23+, CD79b-, and FMC7-. Trisomy 12 and 13q deletions are frequent chromosomal abnormalities. The bcl-2 protein is usually overexpressed. SLL patients present with lymphadenopathy, usually generalized. Lymphocytosis is by definition absent and BM involvement, usually nodular, is found in 25% to 50% of patients. The lymph node lymphocytes are CD5+ and have a similar immunophenotype with CLL, but frequently express the LFA-1 adhesion molecule. Patients are at low risk to develop hypogammaglobulinemia, autoimmune hemolysis, or autoimmune thrombocytopenia. LPL/MW patients may present either with an accidental discovery of IgM gammopathy, symptoms related to paraproteinemia, or lymphadenopathy and/or splenomegaly. The BM is frequently involved and a leukemic picture may be found. A monoclonal gammopathy of IgM class is by definition present in MW and is frequently accompanied by hypogammaglobulinemia. Immunophenotypic studies usually reveal a CD5-, slg+ (moderate), cytoplasmic immunoglobulin (clg)+, FMC7+, and CD38+ cell. A significant proportion of cases carry the translocation t(9;14)(p13;q32) involving the PAX-5 gene. All of these disorders may potentially undergo transformation to large-cell lymphoma or Richter's syndrome. Prognostic factors have been extensively studied in B-CLL, but more studies are needed for SLL and LPL/MW. These entities should be differentiated from other B-chronic small lymphocyte cell disorders, particularly when the latter are leukemic.
The aims of the present study were: (1) to design a sensitive and specific polymerase chain reaction-based method that would allow detection of most common human typical and atypical mycobacterial strains and (2) to apply the method on formalin-fixed paraffin-embedded (FFPE) tissue and sputum samples from patients with clinicopathological evidence of tuberculosis and sarcoidosis. Three sets of primers were selected. The first detects specifically members of the Mycobacterium tuberculosis (M. tuberculosis) complex, amplifying a 243 bp fragment of the gene encoding the immunogenic protein MPB 64, whereas the second traces members of the Mycobacterium avium (M. avium) complex producing a 91 bp fragment of the IS1110 element. The third pair of primers is specific for slow-growing mycobacteria, amplifying a 383 bp region of the 65 kDa mycobacterial antigen gene. Our multiplex polymerase chain reaction assay identified mycobacterial DNA of 10(-3) colony-forming units (CFU)/mL from sputum samples, 10(-5) CFU/mL from FFPE tissue samples and 10(-6) CFU/mL from pure broth cultures. By performing the method on 75 FFPE tissue samples with histological and clinical evidence of tuberculosis and 300 sputum specimens from patients suspected of tuberculosis, we found 38 M. tuberculosis complex, 7 M. avium complex, and 14 slow-growing mycobacteria positive samples in the first case and in the second we found 95 M. tuberculosis complex, 21 M. avium complex, and 35 slow-growing mycobacteria positive samples. The sensitivity of the assay was significantly higher than that of Ziehl-Neelsen and in some cases higher than culture, especially when applied on atypical mycobacteria. In addition, 25 cases histologically and clinically characterized as sarcoidosis were investigated for mycobacterial DNA sequences and in nine of these, DNA corresponding to M. tuberculosis complex was detected. The method described can be applied directly on FFPE and sputum samples and allows not only the detection of mycobacterial DNA, but also an assessment concerning the species involved.
In order to understand better the possible role of cell-cycle regulating molecules in the pathogenesis of Hodgkin's disease (HD), the immunohistochemical distribution pattern of p16INK4A was investigated and compared with pRb, p53, and MDM2 protein status in 44 HD cases. Our findings were correlated to the presence of Epstein-Barr virus as detected by RNA in situ hybridization and clinicopathological parameters. p16INK4A protein immunoreactivity was found in all 44 cases with a proportion of Hodgkin-Reed-Sternberg (HRS) cells ranging from 30 to 90%. In 93% of the cases studied, pRb was detected in HRS, whereas all cases showed overexpression of p53. Almost all specimens (98%) were MDM2-positive as evaluated by 1B10 and/or IF2 monoclonal antibodies. EBER 1/2-transcripts were detected in 31.8% (14 of 44) of the examined samples. A significant correlation was observed between immunoreactivity of p16INK4A and MDM2 and the number of HRS cells (P = .0012 and P = .018, respectively). In a subgroup of cases, with p16INK4A expression in more than 50% of HRS cells, the percentage of pRb-positive neoplastic cells was inversely related to that of p16-positive ones (P = .007). No clinicopathological parameters or clinical prognostic indicators, including duration of response to therapy, were statistically related to the expression levels of any of the four proteins investigated or the presence of Epstein-Barr virus. Our findings suggest that p16 and pRb are regularly expressed and that their pathway in cell-cycle machinery seems to be intact in HD. However, further investigation is needed to shed light on the involvement of cell-cycle molecules in Hodgkin's lymphomagenesis and longer patient follow-up is required for conclusive prognostic correlation.
The p16-pRb and p53-MDM2 pathways represent vital cell cycle checkpoints. Recent studies provide evidence that these pathways are directly linked via MDM2-pRb interaction and p53 suppression of the RB1 gene. In the present study we investigated the alterations of this G1 phase protein network using immunohistochemical and molecular methods in a series of 68 non-small-cell lung carcinomas (NSCLCs) and correlated the findings with clinicopathological features and prognosis of the patients. Aberrant expression (Ab) of p16 and pRb was observed in 33 (49%) and 27 (40%) of the carcinomas, respectively. Analysis of the region that encodes for p16 by deletion mapping, a polymerase chain reaction (PCR)-based methylation assay and PCR single-strand conformation polymorphism (SSCP) analysis revealed that deletions and transcriptional silencing by methylation might represent the main mechanisms of CDKN2/p16ink4a inactivation in NSCLCs. The results of deletion mapping also suggest that other tumor suppressor genes may reside at the 9p21-22 region, which encodes for CDKN2/MTS1/p16ink4a, p14ARF, and MTS2/p15ink4b. In addition, microsatellite instability was observed with a frequency of 16% in the 9p21-22 chromosome area. Overexpression (P) of p53 and MDM2 proteins was found in 39 (58%) and 47 (70%) of the cases, respectively. A highly significant association was observed between p53 overexpression and p53 mutations (P = 0.006). Statistical analysis of the expression patterns of the biologically relevant molecules (p16/pRb, p53/MDM2, MDM2/pRb, and p53/pRb) showed coincident overexpression of p53 and MDM2 (P = 0.04) and that abnormal pRb was correlated with elevated levels of MDM2 (P = 0.013) and p53 (P = 0.01), respectively. We suggest that deregulated expression of these molecules may act synergistically. An important finding of the study was that multiple impairments (three and four molecules affected) of the p16/pRb/p53/MDM2 network occurred in a large proportion (43%) of the carcinomas. This finding in addition to the absence of correlation with clinical stage of the tumors suggests that multiple hits of this network may be a relatively early event in the development of a subset of NSCLCs. The relationship between the factors examined in the present study, clinicopathological features, and survival of the patients did not reveal any significant correlations with the exception of smoking, which was associated with microsatellite alterations (loss of heterozygosity and microsatellite instability) at the 9p21-22 locus (P = 0.04) and the immunophenotypes p53(P)/MDM2(P) (P = 0.04) and p16(Ab)/pRb(Ab)/p53(P)/MDM2(P) (P = 0.03), respectively. We suggest that in a subset of NSCLCs, simultaneous deregulation of the members of this network may represent one way of initiating the oncogenic procedure whereas in other NSCLC subgroups alternative pathways may play this role.
Circulating testosterone concentrations and seminal vesicles weights, as well as thymus and spleen weights and histology were assessed in male Wistar rats from the infantile to post-pubertal period. The widely used anti-estrogenic agent tamoxifen was then administered in adult intact and castrated male rats and its long-term effects on thymic involution and splenic growth were examined. The results showed that: (1) age-related involution of the male thymus from the juvenile period through puberty to post-puberty depends on the rising testosterone levels and represents mainly a decrease of thymic lymphoid-cell elements; (2) tamoxifen administration reverses thymic involution in intact adult male rats and this effect is related to a dose-dependent, tamoxifen-induced castration and decrease of testosterone levels; (3) the changes of circulating testosterone levels, either resulting from maturity, or induced by tamoxifen or by castration, have a minimal effect on splenic growth and weight; and (4) in contrast to intact animals, administration of tamoxifen at pharmacological doses to adult castrated rats results in thymic regression. Underscoring the critical role of testosterone on thymic involution, these findings show that tamoxifen is able to reverse ageing changes in the thymus by suppressing testosterone production, while conversely, exerts thymolytic effects in the absence of androgens.
Histoplasmosis as a serious opportunistic infection in association with AIDS has assumed considerable importance. We have gathered 20 case reports from the literature of oral histoplasmosis in HIV-infected patients. In some cases, oral lesions appear to be the primary or only manifestation of disease. We report one such case of oral histoplasmosis in a bisexual man who was seen with ulcerations on the palate and proved to be infected by HIV.
The present study represents a continuation of previous works in which we observed that lung carcinomas co-expressing MDM2 protein and p53 mutants (mt p53) exhibited more aggressive behaviour. In the above studies, we suggested a 'gain of function' mechanism of mt p53 proteins based on the fact that the MDM2 gene possesses a p53-responsive element (MDM2-p53RE). In this study, to prove our hypothesis, we selected 12 cases from a series of 51 bronchogenic carcinomas. In these 12 cases, we examined the ability of the expressed mt p53 to bind the MDM2-p53RE and correlated the findings with MDM2 expression. Furthermore, we constructed four of these p53 mutants and studied their transactivation properties by co-transfecting them with a reporter plasmid carrying MDM2-p53RE in the p53 null non-small-cell lung carcinoma cell line (NSCLC) H1299. We observed mutant p53 protein DNA-binding activity, which depended on the nature and the position of the amino acid substitution. The fact that the cases with DNA-binding activity were accompanied with MDM2 protein isoforms' overexpression is indicative of a 'gain of function' phenotype. This hypothesis was enforced by the findings of the transfection experiments, which revealed that certain p53 mutants enhanced the expression of the luciferase reporter gene either directly or indirectly via a dominant positive effect on the wild-type p53. In conclusion, this work is one first attempt to examine if the deregulation of the p53/MDM2 autoregulatory feedback loop is due to novel properties of certain p53 mutants in the specific environment of a subset of bronchogenic carcinomas.
We evaluated possible modes of epithelial cell destruction and restoration in minor salivary gland biopsies from patients with SS. Minor salivary gland biopsies from 10 primary Sjögren's syndrome (pSS) patients and eight control individuals were evaluated by immunohistochemical staining for the expression of apoptosis-related molecules, substances released by activated cytotoxic T cells, as well as proteins involved in epithelial cell repair. The results were analysed by computer screen analysis and they were expressed as average percentages. Apoptosis-promoting molecules, Fas antigen and Fas ligand were observed in ductal and acinar epithelial cells as well as in infiltrating mononuclear cells of minor salivary glands from SS patients in comparison with control biopsies. Bax protein, which acts as a death-promoter message, was expressed in the ductal and acinar epithelial cells and in mononuclear infiltrating cells of SS patients compared with control individuals, while Bcl-2, an inhibitor of apoptosis, was primarily found in the lymphocytic infiltrates. In situ DNA fragmentation assay (TUNEL) revealed that epithelial cells were apoptotic in patients with SS compared with control subjects. Immunohistochemical staining for perforin and granzyme B, released from granules of activated cytotoxic lymphocytes, revealed their presence in lymphocytic infiltrates of patients with SS compared with control biopsies. pS2, a member of the trefoil protein family which functions as promoter of epithelial cell repair and cell proliferation, was expressed in epithelial cells in biopsies from SS patients. These studies suggest that the functional epithelium of minor salivary glands in patients with SS appears to be influenced by both intrinsic and extrinsic mechanisms of destruction, while a defensive mechanism of epithelial restoration seems to be active.
AIMS: To evaluate the independent prognostic value of apoptotic versus proliferative fractions in a series of 92 patients with non-Hodgkin's lymphomas (NHL). METHODS AND RESULTS: Apoptotic fractions were quantified by use of the TdT (terminal deoxynucleotidyl-transferase)-mediated in-situ end-labelling technique (TUNEL), the percentage of positive cells constituting the apoptotic index (AI). Proliferative rate was expressed as percentage of Ki67 positive cells (Ki67 LI). Tissues were also stained for p53 protein with the DO-1 antibody. Patients were followed up until death (n = 33) or for an average of 63 months (n = 56). AI increased with malignancy grade and proliferative activity but was not related to location, cell of origin, clinical stage, bone marrow involvement and p53 expression. In multivariate analysis, overall survival was independently influenced by grade, stage, p53 LI and chemotherapy. The independent predictors of disease-free survival were Ki67 LI location and chemotherapy. AI turned out to be the only independent (negative) predictor of post-relapse survival. On the other hand, a low Ki67 LI increased the risk of relapse (logistic regression analysis) whereas a low p53 LI increased the probability of complete response. CONCLUSIONS: Our results suggest that the combined assessment of apoptotic fraction, proliferative rate and p53 expression may provide important prognostic information independent of other clinicopathological parameters in NHL.