In this task, you are given an abstract of article. Your task is to generate title for this article. Preferred titles are under thirty words.

[Q]: Excessive exposure to estradiol represents the main risk factor for endometrial cancer. The abnormally high estradiol levels in the endometrium of women with endometrial cancer are most likely due to overproduction by the tumour itself. Endometrial cancer cells express the genes encoding the steroidogenic enzymes involved in estradiol synthesis. Here we used RT-PCR and Western blot to show that the nuclear receptors SF1 and LRH1, two well-known regulators of steroidogenic gene expression in gonadal and adrenal cells, are also expressed in endometrial cancer cell lines. By transient transfections, we found that SF1 and LRH1, but not the related nuclear receptor NUR77, can activate the promoters of three human steroidogenic genes: STAR, HSD3B2, and CYP19A1 PII. Similarly, forskolin but not PMA, could activate all three promoters. In addition, we found that both SF1 and LRH1 can transcriptionally cooperate with the AP-1 family members c-JUN and c-FOS, known to be associated with enhanced proliferation of endometrial carcinoma cells, to further enhance activation of the STAR, HSD3B2, and CYP19A1 PII promoters. All together, our data provide novel insights into the mechanisms of steroidogenic gene expression in endometrial cancer cells and thus in the regulation of estradiol biosynthesis by tumour cells.
[A]: The nuclear receptors SF1 and LRH1 are expressed in endometrial cancer cells and regulate steroidogenic gene transcription by cooperating with AP-1 factors.

[Q]: DNA polymerase lambda (pol) is a recently identified DNA polymerase whose cellular function remains elusive. Here we show, that pol participates at the molecular level in a chromosomal context, in the repair of DNA double strand breaks (DSB) via non-homologous end joining (NHEJ) in mammalian cells. The expression of a catalytically inactive form of pol (polDN) decreases the frequency of NHEJ events in response to I-Sce-I-induced DSB whereas inactivated forms of its homologues pol and pol do not. Only events requiring DNA end processing before ligation are affected; this defect is associated with large deletions arising in the vicinity of the induced DSB. Furthermore, polDN-expressing cells exhibit increased sensitization and genomic instability in response to ionizing radiation similar to that of NHEJ-defective cells. Our data support a requirement for pol in repairing a subset of DSB in genomic DNA, thereby contributing to the maintenance of genetic stability mediated by the NHEJ pathway.
[A]: The DNA polymerase is required for the repair of non-compatible DNA double strand breaks by NHEJ in mammalian cells

[Q]: AIMS A recent genome-wide association study identified a haplotype block on chromosome 4q25 associated with atrial fibrillation (AF). We sought to replicate this association in four independent cohorts.
METHODS AND RESULTS The Framingham Heart Study and Rotterdam Study are community-based longitudinal studies. The Vanderbilt AF Registry and German AF Network (AFNet) are case-control studies. Participants with AF (n = 3508) were more likely to be male and were older than referent participants (n = 12 173; Framingham 82 +/- 10 vs. 71 +/- 13 years; Rotterdam 73 +/- 8 vs. 69 +/- 9 years; Vanderbilt 54 +/- 14 vs. 57 +/- 14 years; AFNet 62 +/- 12 vs. 49 +/- 14 years). Single nucleotide polymorphism (SNP) rs2200733 was associated with AF in all four cohorts, with odds ratios (ORs) ranging from 1.37 in Rotterdam [95% confidence interval (CI) 1.18-1.59; P = 3.1 x 10(-5)] to 2.52 in AFNet (95% CI 2.22-2.8; P = 1.8 x 10(-49)). There also was a significant association between AF and rs10033464 in Framingham (OR 1.34; 95% CI 1.03-1.75; P = 0.031) and AFNet (OR 1.30; 95% CI 1.13-1.51; P = 0.0002), but not Vanderbilt (OR 1.16; 95% CI 0.86-1.56; P = 0.33). A meta-analysis of the current and prior AF studies revealed an OR of 1.90 (95% CI 1.60-2.26; P = 3.3 x 10(-13)) for rs2200733 and of 1.36 (95% CI 1.26-1.47; P = 6.7 x 10(-15)) for rs10033464.
CONCLUSION The non-coding SNPs rs2200733 and rs10033464 are strongly associated with AF in four cohorts of European descent. These results confirm the significant relations between AF and intergenic variants on chromosome 4.
[A]:
Large scale replication and meta-analysis of variants on chromosome 4q25 associated with atrial fibrillation.