Importance of interleukin 6 in pathogenesis of inflammatory bowel disease

Inflammatory bowel disease (IBD), encompassing ulcerative colitis (UC) and Crohn's disease (CD), is an uncontrolled chronic inflammation of the gastrointestinal tract caused by an interaction of diverse genes and environmental factors. There is growing evidence that cytokine production plays an important role in IBD. One of the key roles in signaling pathway in development of IBD is performed by interleukin 6 (IL-6), although molecular mechanism of this pathway is not yet fully understood. In order to assess the clinical relevance of IL-6 serum concentration in patients with CD and UC we performed cross-sectional, case-control study of IL-6 levels in patients' and healthy blood donors' sera. A total of 100 CD and UC patients and 71 healthy blood donors were investigated. Clinical activity of CD and UC was evaluated using the Crohn's disease activity index and Truelove-Witt's criteria, respectively. Quantitative assessment of serum IL-6 was performed with solid-phase, enzyme-labeled, chemiluminescent sequential immunometric assay. Our results indicate that serum IL-6 is a clinically relevant parameter for CD and UC that strongly correlates with inflammatory activity of disease. We confirmed and extended the role of cytokine production patterns for IBD presentation in Croatian population.

Polymorphisms of interleukin-23 receptor in patients with inflammatory bowel disease in a Croatian tertiary center

The Interleukin-23 signalling pathway is important for the differentiation of TH17 lymphocytes and is involved in the pathogenesis of Inflammatory bowel disease. Polymorphisms in the IL-23 receptor gene were previously found to be associated with Inflammatory bowel disease in various populations. The aim of this study was to determine whether the specific rs11209026 and rs7530511 single-nucleotide polymorphisms in the Interleukin-23 receptor gene are associated with Crohn's disease and ulcerative colitis in a Croatian patient population. A total of 50 patients with Crohn's disease and 93 patients with ulcerative colitis, as well as 99 healthy control subjects were included in the study. The results determined a significantly higher occurrence of rs11209026 in control group compared to patients with inflammatory bowel disease, suggesting a protective effect of this polymorphism. The rs11209026 variant was strongly associated with Crohn's disease, but it was absent in ulcerative colitis. However, there was no significant association between the rs7530511 polymorphism with either ulcerative colitis or Crohn's disease. Associations presented in this study give potentially important insight into the roles of specific Interleukin-23 receptor polymorphisms in Crohn's disease pathogenesis in the Croatian population.

PAX8-PPARgamma oncogene in follicular thyroid tumors: RT-PCR and immunohistochemical analyses

US-guided fine needle aspiration cytology is currently the best diagnostic tool for thyroid nodules. However, it is not sensitive and specific enough for differentiating between benign and malignant follicular tumors. A potentially useful marker for this differentiation is the PAX8-PPARgamma rearrangement, identified in follicular thyroid carcinomas, but not in follicular adenomas or other types of thyroid tumors. The aim of this research was to determine the clinical significance of the PAX8-PPARgamma oncogene in diagnostics follicular thyroid tumors. The study included 62 patients with follicular or Hürthle cell tumors. Gene expression was determined by reverse transcription-polymerase chain reaction (RT-PCR) from paraffin embedded tissues, and PCR products were checked using the agarose gel electrophoresis. The immunohistochemical analysis was performed on archive paraffin embedded tissues with the monoclonal PPARgamma antibody. The statistical analysis has indicated that neither the expression of PAX8-PPARgamma mRNA, nor the immunohystochemical analysis with the PPARgamma antibody correlate with the patohystological diagnosis. The oncogene, PAX8-PPARgamma has not met the expectations as a reliable tumor marker for differentiation between benign and malignant thyroid tumors, which makes the only reliable histological criteria--capsular and vascular invasion.

Non-functional parathyroid gland carcinoma, a rare malignant tumor of the head and neck

Carcinoma of the parathyroid gland is a very rare tumor of the head and neck. The largest number of carcinomas are discovered by chance. (intraoperatively, during surgery removal of the parathyroid gland are adenomas). Around 1% of the primary parathyreoidism is caused by the cancer of parathyroid glands. Only 10% of these rare tumors make up dysfunctional cancer of parathyroid glands. There have been 24 cases reported of this disease in the literature. The focus of our study is to present a case of this disease and to review the published literature to date.

Polymorphisms of vitamin D receptor gene in the population of eastern Croatia with psoriasis vulgaris and diabetes mellitus

The aim of this study was to evaluate the possible association between polymorphisms in the Vitamin D receptor gene (VDR gene) and tendency for development of psoriasis vulgaris and diabetes mellitus in the population of Slavonia, which is a region in the Eastern Croatia. In order to conduct the mentioned evaluation the restriction fragment length polymorphisms (ApaI, BsmI and TaqI) in the Vitamin D receptor gene were researched in three groups of patients: patients suffering only from psoriasis vulgaris, patients suffering only from diabetes mellitus, and patients suffering at the same time from both diseases. Four most common genotypes were found in all standardized control patients: triple heterozygotes BbAaTt (in 29.3% of the studied patients), bbAaTT (in 18.6% of the studied patients), bbaaTT (in 12.9% of the studied patients) and BbAATt (in 8.6% of the studied patients). Three most common VDR 3'-RFLP haplotypes determined in this study were: three-component baT, Bat and bAT haplotype. Results of the Hardy-Weinberg equilibrium showed presence of BsmI polymorphism genotype frequencies disequilibrium in the group of patients suffering from psoriasis and ApaI polymorphism in the group of patients suffering from both diseases. According to the same statistical test all conditions for TaqI polymorphism genotype frequency were fulfilled in all groups of studied patients. There was no significant difference in distribution of BsmI, ApaI or TaqI polymorphism genotype frequencies between control patients and any of the subgroup of studied patients. In studied population none of analysed polymorphisms individually was associated with the risk of development of psoriasis, diabetes or combined phenotype.

[Angiotensin-converting enyme insertion/deletion polymorphism and blood pressure regulation in type 2 diabetic patients]

INTRODUCTION

The renin-angiotensin system (RAS) has been shown to have important role in blood pressure regulation. Inconsistent results have been reported regarding the association of the angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism (NCBI ref. SNP ID: rs1799752) and hypertension as well as a contributing factor in the development of diabetic nephropathy. Aim of the study was to investigate the significance of insertion/deletion polymorphism of angiotensin-converting enzyme as contributing factor to blood pressure regulation in type 2 diabetic patients with diabetic nephropathy and those with preserved renal function.

METHODS

Genomic DNA was extracted from whole blood of 100 patients with diabetic nephropathy and 102 diabetic patients with normal renal function (urinary protein excretion rate less than 300 mg/day and creatinin clearence level > or = 80 ml/min). Blood pressure measurement was done 3 times by a nurse in the supine position, in 15 minutes intervals. Mean arterial pressure (MAP) was calculated according to the standard equation- (systolic pressure + 2 x diastolic pressure)/3, for all measurements. Genotyping was carried out using primers and fluorescent probes in a Lyght Cycler System. Statistical analysis was performed using software package SPSS 16.0 (SPSS inc, Chicago, IL, USA).

RESULTS

Genotype frequencies of the ACE I/D) polymorphysm were in accordance with the Hardy-Weinberg equilibrium. In all subjects, the frequencies of the DD. ID and II genotypes were 0.32; 0.45 and 0.23 respectively. The allelic frequency of the D allele in nephropatby group was 0.82 and 0.72 in the control group. The highest systolic blood pressure was in the subjects with DD genotype. Systolic and mean, arterial pressure were significantly higher in diabetic nephropathy patients compared to patients with preserved kidney function, only if D allele was present (systolic blood pressure: DD t=2,877, p=0,006; ID t=2.733, p=0,008; mean arterial pressure: DD t=2,687, p=0.009; ID t=2,843, p=0,006).

CONCLUSIONS

Individuals with type 2 diabetes mellitus who carry the D allele appear to be susceptible to development of the end stage renal disease. D allele might be an additional risk factor for the uncontrolled hypertension in diabetic nephropathy patients.

The influence of the different morphological changes on gastric mucosa on somatostatin cell number in antrum mucosa and serum somatostatin

The aim of our paper was to investigate the influence of the different morphological changes on gastric mucosa on somatostatin D-cell number in antral mucosa and serum Somatostatin. We analyzed according to Sydney classification to what extent the severity of gastritis affect the observed hormonal values. somatostatin D-cell number in antral mucosa and serum Somatostatin values were compared between three groups of patients; mild, moderate and severe chronic gastritis. The average number of somatostatin cell in biopsy sample of antrum mucosa was 30.41 +/- 35.38 (N = 17) in the case of middle form, 18.69 +/- 26.65 (N = 56) in moderate and in severe case of chronic gastritis 5.23 +/- 5.93 (N = 7) cells in mm2 of mucosa. The level of somatostatin in the serum of middle form gastritis were 26.43 +/- 28.76, moderate 19.95 +/- 35.93 and severe 17.88 +/- 17.66 pg/mL. In order to determine the number of somatostatin cells in antrum mucosa and serum somatostatin with present morphological changes of mucosa, it might helpful to exclude the patients with non-ulcer dyspepsia, but with the higher risk of premalignant and malignant changes.

Comparison of 18F-FDG positron emission tomography and computed tomography in patients with colorectal carcinoma and lymphoma: our initial clinical experience

Findings obtained by fluorine-18-fluorodeoxyglucose positron emission tomography (18F-FDG PET) and computed tomography (CT) were compared in patients with malignant lymphoma and colorectal carcinoma. In 14 malignant lymphoma patients, 16 18F-FDG PET procedures were performed to assess chemotherapy and/or radiotherapy outcome (remission). One patient with clinically overt relapse of non-Hodgkin's lymphoma underwent PET to assess disease dissemination prior to prescribing second-line chemotherapy. Two patients were submitted to PET on two occasions. PET pointed to residual disease in six of 14 patients and was inconclusive in one patient. These patients underwent computed tomography (CT), some of them before and others after PET examination. Then PET and CT findings were compared and therapeutic response, i.e. disease remission was assessed. The signs of residual disease were present in four and absent in nine patients, whereas inconclusive findings in terms of residual disease were recorded in one patient. Although our initial clinical experience was acquired in quite a small number of patients, CT modified clinical evaluation of residual disease in two patients and should be included along with PET in diagnostic work-up of these patients.

Vitamin D endocrine system and psoriasis vulgaris--review of the literature

Vitamin D exerts its physiological functions on calcium and bone metabolism in humans through the active metabolite 1,25-dihydroxyvitamin D3(1,25(OH)2D3). The other spectrum of vitamin D activities includes important effects on cellular proliferation, differentiation and the immune system. These effects are mediated through the intracellularly located vitamin D receptor (VDR). VDR is a member of the steroid, estrogen and retinoid receptor gene family of proteins that mediate transcriptional activities of the respective ligands. The VDR complex binds in the nucleus to the vitamin D responsive element on the gene. Several polymorphisms of the vitamin D receptor (VDR) gene have been described including FokI in exon 2, BsmI and ApaI in intron 8 and TaqI in exon 9. Alterations in vitamin D-1,25 (OH)2D3 levels and polymorphisms of VDR gene have been shown to be associated with several malignant or autoimmune diseases such as sclerosis multiplex, breast cancer, diabetes mellitus, malignant melanoma, and psoriasis vulgaris. The effects of VDR gene polymorphisms including immunomodulation, stimulation of cellular differentiation and inhibition of proliferation make it a possible candidate for therapy of psoriasis as well as for the psoriasis gene modification. The objective of this article is to present the state-of-the-art in the VDR gene polymorphism research in psoriasis vulgaris.

Association of vitamin D receptor gene 3'-variants with Hashimoto's thyroiditis in the Croatian population

Hashimoto's thyroiditis (HT) is the most frequent autoimmune thyroid disease with strong genetic background. Vitamin D receptor (VDR) endocrine system affects immunosuppressive, regulatory and tolerogenic decisions required for induction and maintenance of peripheral immune tolerance. With respect to the biological function of the VDR and functionally plausible gene-expression data, we sought to test whether particular 3'-restriction fragment length polymorphisms (RFLP) and haplotypes previously directly or indirectly associated with VDR mRNA 3'-allelic imbalance phenotype and differences in total VDR mRNA expression are implicated in HT susceptibility. Thus, 145 Croatian HT patients and 145 age-, sex- and ethnically matched euthyroid controls were genotyped for VDR rs1544410 (BsmI), rs7975232 (ApaI) and rs731236 (TaqI) polymorphisms by polymerase chain reaction-RFLP method. Covariate-adjusted single-locus and haplotype-phenotype regression analyses were performed. Permutation corrections (P(c)) and Akaike Information Criteria were used for model comparisons. The best-fit [global P(c) = 7.2 x 10(-4)]BsmI-TaqI BT haplotype was found significantly more often in subjects without HT [12.2% vs. 3.7%; odds ratio (OR, 95% confidence intervals) = 0.28 (0.14-0.56), P(c) = 8 x 10(-4)], whereas the bT haplotype was significantly more frequent in individuals with HT [45.7% vs. 61.8%; OR = 1.91 (1.37-2.65), P(c) = 4 x 10(-4)]. Two extended BsmI-ApaI-TaqI RFLP haplotypes, the common baT [35.7 vs. 47.3%, OR = 1.63 (1.17-2.27), P(c) = 0.012] and rare BaT variants [6.5 vs. 1.2%, OR = 0.17 (0.06-0.55), P(c) = 1.2 x 10(-3)] were associated with HT, representing predisposing and protective haplotypes, respectively. In single-RFLP association analyses, only rs1544410 polymorphism was associated with HT phenotype (allelic P(c) = 0.0078) and appeared to function under the recessive model, with decreased risk of HT among the BB homozygotes [OR = 0.39 (0.21-0.7), P(c) = 0.0052] when compared to the reference b(+)-genotypes. These data suggest that common haplotypic variants within the VDR gene 3'-region previously linked to VDR mRNA expression and allelic imbalance could be associated with HT in the general population, and thus, may be involved in the pathogenesis of HT.

Association of vitamin D receptor gene polymorphism with susceptibility to Graves' disease in Eastern Croatian population: case-control study

AIM

To evaluate the effect of vitamin D3 receptor (VDR) gene BsmI/ApaI/TaqI restriction fragment length polymorphisms on Graves' disease susceptibility in a subset of patients from Eastern Croatia.

METHODS

Graves' disease patients (n=110) and ethnically matched euthyroid controls (n=99) with no clinical evidence or family history of thyroid or autoimmune diseases were genotyped for VDR gene polymorphisms by BsmI/ApaI/TaqI endonuclease digestion after polymerase chain reaction amplification with sequence-specific primers. Data were analyzed by chi-square-test, and crude odds ratios (OR) with 95% confidence interval (95% CI) were calculated.

RESULTS

The ApaI "AA" (14.5% vs 30.3%, patients vs controls, respectively, OR=0.39, 95% CI [0.2-0.77], P=0.01) and BsmI "BB" (7.3% vs 23.2%, OR=0.26 [0.11-0.61], P=0.002) genotypes were significantly underrepresented in patients, whereas ApaI "aa" (28.2% vs 9.1%, OR=3.92 [1.76-8.74], P=0.001) and TaqI "TT" (51.8% vs 31.3%, OR=2.36 [1.34-4.16], P=0.004) genotypes were significantly more frequent in patients than controls. The genotype combination, which conferred the strongest protection against Graves' disease, was "BBAAtt" (2.7% vs 17.2%, OR=0.14 [0.04-0.48], P=0.001).

CONCLUSION

These findings suggest that VDR gene BsmI/ApaI/TaqI polymorphisms are associated with Graves' disease susceptibility in a subset of patients from Eastern Croatia. The ApaI and BsmI "AA" and "BB" genotypes, respectively, as well as combined "BBAAtt" genotype, appeared to confer protection against Graves' disease, whereas ApaI "aa" and TaqI "TT" genotypes were associated with an increased risk for Graves' disease. However, the true mechanisms of association remain to be elucidated.

Metabolic effects of novel N-1-sulfonylpyrimidine derivatives on human colon carcinoma cells

Novel N-1-sulfonylpyrimidine derivatives have a strong antiproliferative activity and an ability to induce apoptosis in treated tumor cells. The purpose of this study was to elucidate the effects of two N-1-sulfonylpyrimidine nucleobases on catalytic activity of tumor cells' enzymes involved in DNA and RNA synthesis, and in de novo and salvage pyrimidine and purine syntheses. Investigations were performed in vitro on colon carcinoma cells (Caco2). The biosynthetic activity of the tumor cells' enzymes was determined using sensitive radio-assays. Enzyme activity in treated cells was calculated relative to untreated control cells. Both of the investigated compounds, 1-(p-toluenesulfonyl) cytosine (TsC) and 5-bromo-1-(methanesulfonyl) uracil (BMsU) inhibited activities of specific enzymes involved in nucleic acid synthesis. BMsU strongly inhibited activities of DNA polymerase alpha (53%), thymidine kinase (68%), thymidilate synthase (43%), and ribonucleotide reductase (46%). De novo biosynthesis of pyrimidine and purine was reduced by 20%. TsC was able to inhibit RNA polymerase (37%), orotate phosphoribosyltransferase (39%), uridine kinase (44%), ribonucleotid reductase (47%), and de novo purine synthesis (61%). Antitumor activity of 1-(p-toluenesulfonyl) cytosine (TsC) and 5-bromo-1-(methanesulfonyl) uracil (BMsU) is closely associated with their inhibitory activity on enzymes that play an important role in the metabolism of tumor cells.