Androgenetic alopecia and polymorphism of the androgen receptor gene (SNP rs6152) in patients with benign prostate hyperplasia or prostate cancer.

BACKGROUND: Both androgenetic alopecia (AGA) and carcinoma of the prostate (CaP) or benign prostatic hyperplasia (BPH) are androgen-dependent disorders. OBJECTIVE: To investigate the relationships between male androgenetic alopecia, androgen receptor (AR) gene polymorphism (SNP rs6152) and clinical characteristics of BPH and prostate cancer. METHODS: Overall, 309 male subjects with prostate disease (BPH or CaP) were examined. We evaluated the standard grades of AGA (I-VII) by Hamilton-Norwood classification and 195 patients were also assessed by phototrichogram. Prostate-specific antigen (PSA) and testosterone levels were also measured. Polymorphism rs6152 of the AR was evaluated from blood samples by PCR-RFLP. Data were statistically evaluated. RESULTS: The expected positive correlation between age and AGA grade and the expected negative correlation between hair density and age and between anagen/telogen and AGA were found. A statistically significant difference between patients with A and G alleles in terms of AGA grade was found. The predominant G allele was more frequent in patients with higher grade of alopecia and in patients with significantly higher PSA. There was no correlation between diagnosis (BPH or CaP) and polymorphism. Patients with prostate inflammation had a statistically significant higher grade of AGA, together with higher PSA. CONCLUSIONS: We confirmed that the AR gene polymorphism (SNP rs6152 G>A) is associated with the development of AGA and higher PSA levels in patients with BPH but not cancer. A novel finding of our study is that BPH patients with prostate inflammation had a significantly higher grade of AGA together with significantly higher PSA levels.

Binding of AR to SMRT/N-CoR complex and its co-operation with PSA promoter in prostate cancer cells treated with natural histone deacetylase inhibitor NaB.

Signaling through the androgen receptor (AR) plays a critical role in prostate cancer progression. The AR is a classical nuclear receptor (NR) providing a link between signaling molecule and transcription response. Histone deacetylase inhibitors- (HDACI) have antiproliferative and proapoptotic effects on prostate cancer cells and their implication in silence AR signaling may have potential therapeutic use. We aimed to study the inhibitory effects of the corepressor SMRT (Silencing Mediator for Retinoid and Thyroid -hormone receptors) which forms a complex together with nuclear receptor corepressor (N-CoR) and with histone deacetylase 3 (HDAC3) on AR activity.The androgen-sensitive prostate cancer cell line LNCaP and androgen-insensitive prostate cancer cell line C4-2 both AR-positive, and androgen-insensitive DU145 and PC3 prostate cancer cell lines were treated with two HDACIs, sodium butyrate (NaB) and/or trichostatin A (TSA). We amplified immunoprecipitated DNA by conventional PCR and in the -following step we used the chromatin immunoprecipitation (ChIP) analysis coupled with quantitative PCR for monitoring NaB induced formation of AR-SMRT/N-CoR complex binding on the PSA promoter. The co-immunoprecipitation assay revealed increase in AR-SMRT formation in NaB treated cells. Simultaneously, the Western blot analysis showed a significant decrease in AR protein expression. In conclusion, the inhibitory effect of NaB on AR gene expression seems to be specific and unique for prostate cancer AR-positive cell lines and corresponds with its ability to stimulate AR-SMRT complex formation. We suggest that AR and SMRT/N-CoR corepressors may form a stable complex in vitro and NaB may facilitate the interaction between AR nuclear steroid receptor and SMRT corepressor prote.

Histone acetylation and methylation in the signaling of steroid hormone receptors.

Molecular changes associated with malignancy are extremely complex. Early epigenetic events occurring in the common tumor types such as breast or prostate cancer might determine the subsequent genetic changes leading to tumor development and progression. Covalent modifications of histones play a major role as determiners of epigenetic information and are important in the regulation of gene expression. Acetylation generally correlates with transcriptional activation, while methylation can signal either activation or repression. However, little is known about the interplay of different epigenetic events. Steroid hormones regulate many cellular processes through signal transduction pathways that result in a variety of post-translational modifications. Such modifications can be triggered by steroid hormones in cooperation with coactivators(p160 family proteins, CBP, p300, p/CAF) and/or corepressors (N-Cor, SMRT, TZF). There is still much to learn about their regulation and the molecular and physiological consequences of these modifications.

DNA vaccination against v-src oncogene-induced tumours in congenic chickens.

DNA vaccination is particularly efficient for induction of cytotoxic T-lymphocyte (CTL) response. In our experiments, we used MHC(B) congenic chicken lines CB and CC (regressors and progressors of v-src-induced tumours, respectively) and a mutated, non-oncogenic v-src gene construct as the DNA vaccine. A high degree of vaccine protection against oncogenic v-src challenge was achieved in the CB line chickens. CTL response was demonstrated in vitro and by adoptive transfer of immune cells to the syngeneic host and to the CC line chickens rendered tolerant to CB cells. In the CC line chickens we observed tumour growth retardation after a low-dose DNA vaccination administered to immature recipients while higher amounts of DNA vaccine in immunocompetent chickens exerted an enhancing effect.

Polymorphism of Old Kladruber horses, a surviving but endangered baroque breed.

Analysis of MHC class I and class II polymorphism, as well as data from other polymorphic systems (non-MHC lymphocyte alloantigen, blood groups systems, biochemical polymorphisms and microsatellite loci), was used to characterize the extent and distribution of the genic polymorphism of Kladruber horses. A breed-characteristic distribution of the MHC polymorphism was found. The repertoire of defined MHC class I specificities was restricted, especially in the grey subpopulation and in stallions, but a high frequency of blanks suggests the possible existence of undetected specificities. Despite the small population size and a relatively high degree of inbreeding, high heterozygosity in MHC haplotypes has been conserved. The extent of polymorphism and the degree of heterozygosity in other loci were also relatively high. A comparison of the two existing subpopulations, grey and black, at all the loci tested, including RAPD markers, characterized them as genetically distinct, although clearly related. The genetic distances between them were of the same order of magnitude as between distinct breeds. The results may be useful in defining short-term and long-term breeding policy within the breed and for further studies of associations with disease and other traits.

BoLA DYA polymorphism in Czech cattle.

Polymorphism at the BoLA DYA locus was determined in two groups of Czech Black Pied cattle by PCR-RFLP detecting substitutions at nucleotide positions 112 and 219. Animals for this study were nonrandomly selected according to their health status in two BoLA-associated infections: bovine leukosis (n = 59) and Johne's disease (n = 36). A group of noninfected Czech Red Pied cows (n = 37) was used for comparison. The frequencies of DYA alleles and haplotypes were virtually identical in the two selected groups as well as in the infection-free animals. In contrast, distribution of BoLA DRB3.2 alleles differed considerably between the infected groups as expected based on the previously detected associations with BoLA. The results suggest that the polymorphism of the DYA unexpressed gene was not influenced by selecting animals for this study according to their health status.

Mhc-DRB genes and the origin of New World monkeys.

The major histocompatibility complex (Mhc) is a family of loci characterized by its relatively rapid evolutionary turnover, large genetic distances between genes, and long persistence of allelic lineages effected by balancing selection. These features render the Mhc highly suitable for answering questions concerning speciation and adaptive radiation. The aim of the present study was to use Mhc-DRB genes to make inferences about the founding population of the Platyrrhini. Three segments, each approximately 300 base pairs in length, of the platyrrhine DRB genes were amplified by the polymerase chain reaction and sequenced. The segments were derived from intron 2, exon 3, and exon 6 of DRB genes from different species of New World monkeys. The results of the study have revealed that on a phylogenetic tree, all of the tested platyrrhine genes appear to form a single cluster, while all catarrhine DRB genes form a distinct cluster, although the bootstrap values fail to provide statistically significant support for the separation of these two clades. This observation suggests that the multiple platyrrhine genes originated from a single ancestral gene after the divergence of the Platyrrhini and Catarrhini and thus contradicts the results of an earlier study in which some exon 2 DRB sequences appeared to predate the split of the two primate groups. The inconsistency in the DRB gene phylogeny can be explained by postulating convergent evolution for the peptide-binding region of the DRB exon 2 sequences. The phylogeny of the platyrrhine DRB genes (except for exon 2) is relatively "shallow"; the distances between genes are relatively short (in comparison to the catarrhine DRB genes), and there is a tendency for sequences of individual species to cluster together. The phylogeny of the platyrrhine DRB genes is consistent with the postulate that a small population founded the group and that there is an ongoing adaptive radiation from small, relatively isolated founding populations.

Mhc-DRB genes of platyrrhine primates.

The two infraorders of anthropoid primates, Platyrrhini (New World monkeys) and Catarrhini (Old World monkeys and the hominoids) are estimated to have diverged from a common ancestor 37 million years ago. The major histocompatibility complex class II DRB gene and haplotype polymorphism of the Catarrhini has been characterized in several recent studies. The present study was undertaken to obtain information on the DRB polymorphism of the Platyrrhini. Fifty-five complete exon 2 DRB sequences were obtained from six species of Platyrrhini representing both the Callitrichidae and the Cebidae families. Combined with the results of a parallel contig mapping study, our data indicate that at least three loci (DRB1*03, DRB3, and DRB5) are shared by the Catarrhini and the Platyrrhini. However, the three loci are occupied by functional genes in the former infraorder and mostly by pseudogenes in the latter. Instead of the pseudogenes, the Platyrrhini have evolved a new set of apparently functional genes-DRB11 and DRB*W12 through DRB*W19, which have thus far not been found in the Catarrhini. The DRB*W13, *W14, *W15, *W17, *W18, and *W19 genes seem to be restricted to the Cebidae family, whereas the DRB*W16 locus has so far been documented in the Callitrichidae family only. The DRB alleles of the cotton-top tamarin, and perhaps also those of the common marmoset (both members of the family Callitrichidae), are characterized by low nucleotide diversity, possibly indicating that they diverged from a common ancestral gene relatively recently.