Occurrence of BRAF mutations in a Polish cohort of PTC patients - preliminary results.

INTRODUCTION: Genetic alterations involving the mitogen-activated protein kinase (MAPK) pathway are frequently demonstrated in papillary thyroid cancer (PTC). BRAF(V600E), the most frequent mutation in adult patients, is present in approximately 50% of PTC. Most clinical studies have demonstrated an association of BRAF(V600E) mutation with aggressive clinicopathological characteristics and high tumour recurrence, although the results are controversial. In this study we present the preliminary results of BRAF mutation frequence in a group of 88 Polish patients with papillary thyroid cancer (PTC) and relate it to the outcome all DTC patients operated in 2004 and 2005. BRAF (V600E) mutation was diagnosed in 38 (43%) of cases. MATERIAL AND METHODS: The presence of BRAF mutation was evaluated in 88 PTC tumours. DNA was isolated from tissue parafin blocks, and the mutation V600E was evaluated by sequence analysis with an AbiPrism 377 and 3130 xl genetic analyzer (Life Technologies). Statistical analysis was carried out with the use of SPSS 12 software. The chi² and Kaplan-Meyer survival analysis were performed. RESULTS: From all analyzed clinico-pathological factors, only older age positively correlated with BRAF mutation frequency (p = 0.0017). Lymph node/distant metastases, multifocality, and extra-thyroid extension did not correlate with BRAF status. One cancer related death and two reccurences were observed in the BRAF+ group while one relapse was diagnosed in the BRAF- group. CONCLUSIONS: Although many studies document BRAF mutation as a prognostic factor in PTC our results underline that it is too early to consider it as a routine clinical predictive factor.

Locus 1q21 Gene expression changes in atopic dermatitis skin lesions: deregulation of small proline-rich region 1A.

BACKGROUND: Discovery of the significant impact of filaggrin (FLG) mutations on the genetic predisposition to atopic dermatitis (AD) focused attention on the 1q21 locus, where not only FLG but also other epidermal genes are located. In the present study, we compared 1q21 gene expression in lesional versus nonlesional AD skin. METHODS: A real-time quantitative PCR analysis of 10 1q21 genes, selected on the basis of a previous microarray study, was performed in skin biopsies from 33 individuals with AD. Three alternative pathway keratins were also evaluated. RESULTS: In chronic AD skin lesions, we observed an increase in RNA encoding involucrin, S100 calcium-binding proteins A2 and A7-A9 and small proline-rich region (SPRR) proteins 1A and 2C, with fold changes ranging from 2.0 for S100A2 to 15.4 for S100A8 (p < 0.001, Bonferroni corrected), in parallel to the overexpression of the alternative pathway keratins 6A, 6B and 16. The loricrin (LOR) expression level was significantly decreased in lesional AD skin (fold change 0.5; p < 0.01). The expression of the majority of 1q21 genes and alternative keratins was closely correlated; however, for SPRR1A (and SPRR2C) in lesional skin, the correlation with other genes was lost. CONCLUSIONS: We hypothesize that the deregulated increase in SPRR1A expression in chronic atopic skin lesions reflects an insufficient rise in SPRR transcripts, unable to compensate for the lack of LOR and thus contributing to the persistence of chronic AD skin lesions. Turning off the stress response in the skin may be regarded as a goal in the treatment of AD skin lesions, and SPRR genes might be targets for such an approach.

The HspA2 protein localizes in nucleoli and centrosomes of heat shocked cancer cells.

The human HSPA2 gene, which belongs to the HSP70 family of heat shock genes, is a counterpart of rodent testis-specific HspA2 gene. Rodent genes are expressed mainly in pachytene spermatocytes, while transcripts of human HSPA2 gene have been detected in various normal somatic tissues, albeit translation of the messenger RNA into corresponding protein has not been yet unambiguously demonstrated, except for several cancer cell lines. The aim of our work, a first step in search for HspA2 function in cancer cells, was to establish its intracellular localization at physiological temperature and during heat shock. First, we used qRT-PCR and a highly specific antibody to select cell lines with the highest expression of the HspA2 protein, which turned out to be A549 and NCI-H1299 lines originating from non-small cell lung carcinoma (NSCLC). Significant expression of the HspA2 was also detected by immunohistochemistry in primary NSCLC specimens. Intracellular localization of the HspA2 was studied using both the specific anti-HspA2 polyclonal antibody and transfection of cells with fusion proteins HspA2-EGFP and mRFP-HspA2. We found that, at physiological temperature, the HspA2 was localized primarily in cytoplasm whereas, during heat shock, localization shifted to nucleus and nucleoli. Moreover, we demonstrate that in heat-shocked cells HspA2 accumulated in centrosomes. Our results suggest that the HspA2, like Hsp70 protein, can be involved in protecting nucleoli and centrosomes integrity in cancer cells subjected to heat shock and, possibly, other cellular stressors.

[Expression of selected genes involved in transport of ions in papillary thyroid carcinoma]. / Ekspresja wybranych genów zaangazowanych w transport jonóww raku brodawkowatym tarczycy.

INTRODUCTION: The studies of papillary thyroid cancer (PTC) gene expression profile have shown changes in expression of genes involved in transport of several ions. The aim of our study was a real-time PCR evaluation of three of them: KCNJ2, SLC4A4 and SLC34A2. MATERIAL AND METHODS: The analysis was carried out in PTC tumors and normal thyroid samples gained from 38 patients. Real-time quantitative PCR (Q-PCR) was performed (Taqman) with beta-glucuronidase (GUS) as the reference gene. RESULTS: We observed 20 x increase of SLC34A2 expression in PTC. This gene encodes Na+/PO(4) (3-) cotransporter. Considerable increase of gene expression has been shown also for KCNJ2, encoding a potassium ion channel. SLC4A4, which encodes the Na+/HCO(3) (2-) cotransporter, exhibited a 7-fold decrease in PTC. CONCLUSIONS: The performed study revealed that SLC34A2 gene exhibited the most distinct change in expression and may become a molecular marker of papillary thyroid cancer.

Interaction of HLA-DRB1 alleles with CTLA-4 in the predisposition to Graves' disease: the impact of DRB1*07.

OBJECTIVE: To study interactions between the two most widely confirmed Graves' disease (GD) loci: HLA-DRB1 and CTLA-4. HLA-DRB1*03 (risk allele) and DRB1*07 (protective allele) were analyzed in this aspect, the linked TNF G(-308)A polymorphism was also considered. DESIGN: A case-control study of 429 patients with GD compared to 308 healthy subjects. The impact of genes and their interactions were analyzed by stepwise logistic regression. RESULTS: The independent effects of DRB1*03 and DRB1*07 were confirmed in our study both by stratification studies and logistic regression. CTLA-4 did not appear to be associated with GD when the interactions with other genes were considered. By logistic regression we observed a significant interaction between DRB1*07 and CTLA-4 and revealed that CTLA-4 49G attenuated the DRB1*07-related protection, the effect noticed also in three-way stratification studies. We confirmed that the TNF G(-308)A polymorphism is only a marker of the DRB1 status. CONCLUSION: Our results stress the importance of complex gene interactions in the multigene predisposition to GD. The interactions between two predisposing loci, DRB1 and CTLA-4, are exerted rather by DRB1*07 than DRB1*03 allele: CTLA-4 acts via switching off the protective DRB1*07 influence, whereas the effect of DRB1*03 is independent.

Association of CD40 gene polymorphism (C-1T) with susceptibility and phenotype of Graves' disease.

OBJECTIVE: Recently, a functional polymorphism in the CD40 gene at position -1, C to T change (C-1T) has been identified and the C/C genotype has been reported to be associated with Graves' disease (GD). DESIGN: We performed a case-control, replication study on 556 patients with GD and 611 healthy subjects in a Polish population. Furthermore, we analyzed the distribution of CD40 genotypes in subgroups of patients with GD divided according to age of onset, gender, family history, tobacco smoking, ophthalmopathy, and genetic parameters (CTLA4 49G, PTPN22/LYP 1858T or HLA-DRB1*03 alleles). RESULTS: Although the frequency of C/C genotype was increased in GD compared to controls, the difference was not significant (60.5% versus 55.8%, p = 0.062, odds ratio [OR] = 1.21, 95% confidence interval [CI]: 0.96-1.53). Because our study was underpowered to detect such a modest association, we performed a meta-analysis with the data from previous studies. The combined OR for the C/C genotype as a risk factor for GD was 1.22 (95% CI: 1.08-1.38, p = 0.001). We failed to find an interaction between CD40 genotypes and other GD susceptibility alleles. No significant genotype-phenotype associations were found. CONCLUSIONS: Our results support the notion that CD40 C-1T polymorphism has a modest effect on genetic susceptibility to sporadic GD.