Plasma concentrations of the atherogenic lipoprotein(a) (Lp(a)) are predominantly determined by inherited sequences within or closely linked to the apolipoprotein(a) gene locus. Much of the interindividual variability in Lp(a) levels is likely to originate at the level of apo(a) gene transcription. However, the liverspecific apo(a) basal promoter is extremely weak and does not exhibit common functional variations that affect plasma Lp(a) concentrations. In a search for additional apo(a) gene control elements, we have identified two fragments with enhancer activity within the 40-kilobase pair apo(a)-plasminogen intergenic region that coincide with DNase I-hypersensitive sites (DHII and DHIII) observed in liver chromatin of mice expressing a human apo(a) transgene. Neither enhancer exhibits tissue specificity. DHIII activity was mapped to a 600-base pair fragment containing nine DNase I-protected elements (footprints) that stimulates luciferase expression from the apo(a) promoter 10 -15-fold in HepG2 cells. Binding of the ubiquitous transcription factor Sp1 plays a major role in the function of this enhancer, but no single site was indispensable for activity. DHIII comprises part of the regulatory region of an inactive long interspersed nucleotide element 1 retrotransposon, raising the possibility that retrotransposon insertion can influence the regulation of adjacent genes. DHII enhancer activity was localized to a 180-base pair fragment that stimulates transcription from the apo(a) promoter 4 -8-fold in HepG2 cells. Mutations within an Sp1 site or either of two elements composed of direct repeats of the nuclear hormone receptor half-site AGGTCA in this sequence completely abolished enhancer function. Both nuclear hormone receptor elements were shown to bind peroxisome proliferator-activated receptors and other members of the nuclear receptor family, suggesting that this enhancer may mediate drug and hormone responsiveness.

A detailed long range restriction map of the region de®ned by markers D6S149 and D6S193 on chromosome 6q27 has been constructed. This was achieved by YAC cloning and contig assembling of the same region. Seven YAC clones were found to span the almost 1000 Kb region¯anked by the two markers which on the genetic map resulted to be 1.9 cM apart. With some of the characterized YAC clones we undertook a molecular cytogenetic analysis of 20 benign ovarian tumors. The rationale for this was the recent mapping to a region of chromosome 6q27,¯anked by markers D6281 and D6S133, of a locus for the SV40-mediated immortalization of human cells (SEN6 gene). Noteworthy we found that the the D6S149-D6S193 region (comprised in the larger D6S281-D6S133 physical interval) was altered in all samples analysed adding support to the occurrence of a immortalization step in this type of tumors.

In all species studied, the basic fibroblast growth factor (bFGF) gene is transcribed into multiple mRNAs, one of which is an antisense RNA (1B FGF-AS) probably involved in regulating the stability of the sense transcript. In this study we investigated whether the regulatory mechanisms of bFGF expression might be altered in endometrial stromal cells derived from women with endometriosis. bFGF and 1B FGF-AS mRNA levels were quantified in primary cultures of eutopic endometrial stromal cells derived from 29 women without endometriosis and 24 patients affected by the disease. When the data were analyzed according to the phase of the menstrual cycle, endometrial stromal cells derived from patients in the late proliferative phase showed significantly higher bFGF mRNA values and significantly lower 1B FGF-AS mRNA levels compared with control samples. Furthermore, the mean bFGF/1B FGF-AS mRNA ratio was significantly higher in endometrial stromal cells derived from patients compared with that in controls (mean +/- SEM, 2.31 +/- 0,55 and 0.77 +/- 0.14, respectively; P = 0.009). Moreover, for bFGF expression the differences existing at the mRNA level were maintained at the protein level. These findings support the hypothesis that 1B FGF-AS mRNA could regulate the expression of the sense transcript and suggest that in endometrial cells derived from patients, the presence of higher bFGF levels could improve their ability to proliferate at the ectopic site.

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We studied the potential role of innovative diagnostic tools for the management of patients with differentiated thyroid cancer (DTC). Several methods for the detection of the tumor marker thyroglobulin (Tg) have been employed in 36 patients in apparent remission at the moment of the study. All patients had negative anti-Tg antibodies and were evaluated during L-T(4) suppressive therapy before and after stimulation with recombinant human TSH (rhTSH). Serum Tg was measured by means of conventional [nonhighly sensitive (nhs)] or highly sensitive (hs) immunoassays with positive cut-off values set at 1.0 and 0.18 microg/liter, respectively. The RT-PCR conditions for the qualitative determination of Tg mRNA from peripheral blood were optimized to prevent interference by illegitimate transcription. The patients have been classified on the basis of a hs-basal Tg testing by taking into account the results of their baseline samples in hs immunoassay and RT-PCR method; hs-basal Tg testing was considered positive when the marker was detectable in at least one of the two tests. The predictive value of hs-basal Tg testing was estimated on the basis of a global clinical evaluation, including serum Tg response after rhTSH stimulation and reports of contemporary (131)I scan and neck ultrasound. The clinical evaluation was considered positive when at least one of these criteria yielded positive results. Although nhs-Tg measurement was poorly predictive of the clinical status, basal hs-Tg evaluation was found to be concordant with the clinical evaluation in 71% of cases. Results of basal Tg mRNA detection did not vary after rhTSH stimulation and were concordant with the clinical evaluation in 66% of cases. Tg mRNA evaluation alone showed 10 apparently false-positive results, and serum basal hs-Tg was falsely negative in 11 additional cases, suggesting that a suitable predictability could be obtained by the association of these 2 parameters. Indeed, the combination of hs-Tg assay and mRNA detection in the hs-basal Tg testing allowed the identification of 22 patients with a positive persistent/recurrent disease or normal thyroid residue, as well as identification of all 6 patients with a negative clinical evaluation. In conclusion, the combined evaluation of circulating Tg mRNA and serum Tg by means of hs noncompetitive immunoassay (hs-basal Tg testing) can give useful information on the clinical status of patients with DTC who are apparently disease-free, even on L-T(4) TSH-suppressive therapy. Therefore, these combined evaluations retain a potential role in the clinical monitoring of DTC patients. In particular, a negative hs-basal Tg testing would indicate disease remission and the opportunity to lengthen the intervals between rhTSH stimulations and/or to shift patients to a less profound TSH suppression with L-T(4).