The cyclooxygenase (COX)-2 gene encodes an inducible prostaglandin synthase enzyme that is overexpressed in adenocarcinomas and other tumors. Deletion of the murine Cox-2 gene in Min mice reduced the incidence of intestinal tumors, suggesting that it is required for tumorigenesis. However, it is not known if overexpression of Cox-2 is sufficient to induce tumorigenic transformation. We have derived transgenic mice that overexpress the human COX-2 gene in the mammary glands using the murine mammary tumor virus promoter. The human Cox-2 mRNA and protein are expressed in mammary glands of female transgenic mice and were strongly induced during pregnancy and lactation. Female virgin Cox-2 transgenic mice showed precocious lobuloalveolar differentiation and enhanced expression of the ␤-casein gene, which was inhibited by the Cox inhibitor indomethacin. Mammary gland involution was delayed in Cox-2 transgenic mice with a decrease in apoptotic index of mammary epithelial cells. Multiparous but not virgin females exhibited a greatly exaggerated incidence of focal mammary gland hyperplasia, dysplasia, and transformation into metastatic tumors. Cox-2-induced tumor tissue expressed reduced levels of the proapoptotic proteins Bax and Bcl-x L and an increase in the anti-apoptotic protein Bcl-2, suggesting that decreased apoptosis of mammary epithelial cells contributes to tumorigenesis. These data indicate that enhanced Cox-2 expression is sufficient to induce mammary gland tumorigenesis. Therefore, inhibition of Cox-2 may represent a mechanism-based chemopreventive approach for carcinogenesis.

OBJECTIVETo investigate the efficacy, safety, and tolerability of empagliflozin in patients with type 2 diabetes and hypertension. RESEARCH DESIGN AND METHODSPatients (N = 825) with type 2 diabetes and hypertension (mean seated systolic blood pressure [SBP] 130-159 mmHg and diastolic blood pressure [DBP] 80-99 mmHg) were randomized (double blind) to 10 mg or 25 mg empagliflozin or placebo once daily for 12 weeks. RESULTSAt week 12, adjusted mean difference versus placebo in change from baseline in mean 24-h SBP (ambulatory blood pressure monitoring [ABPM]) was 23.44 mmHg (95% CI 24.78, 22.09) with 10 mg empagliflozin and 24.16 mmHg (25.50, 22.83) with 25 mg empagliflozin (both P < 0.001). At week 12, adjusted mean difference versus placebo in change from baseline in mean 24-h DBP (ABPM) was 21.36 mmHg (95% CI 22.15, 20.56) with 10 mg empagliflozin and 21.72 mmHg (95% CI 22.51, 20.93) with 25 mg empagliflozin (both P < 0.001). Changes in office BP were consistent with ABPM. Adjusted mean difference versus placebo in change from baseline in HbA 1c at week 12 was 20.62% (95% CI 20.72, 20.52) (26.8 mmol/mol [95% CI 27.9, 25.7]) with 10 mg empagliflozin and 20.65% (95% CI 20.75, 20.55) (27.1 mmol/mol [95% CI 28.2, 26.0]) with 25 mg empagliflozin (both P < 0.001). Empagliflozin was well tolerated. One patient on placebo and one patient on 10 mg empagliflozin reported events consistent with volume depletion. CONCLUSIONSEmpagliflozin was associated with significant and clinically meaningful reductions in BP and HbA 1c versus placebo and was well tolerated in patients with type 2 diabetes and hypertension.The lifetime risk of cardiovascular disease in patients with diabetes is 67-78% (1). Management of patients with type 2 diabetes should not only aim to control glycemia but also include the modification of cardiovascular risk factors (2,3). Hypertension affects approximately two-thirds of patients with diabetes (4,5) and is a significant contributing factor to cardiovascular complications (3,6). Lowering blood pressure (BP) has been shown to reduce cardiovascular events in patients with diabetes and to exert a renoprotective effect (3,7,8). The Joint National Committee (JNC) 2003 guidelines recommended targets of systolic BP (SBP) ,130 mmHg and diastolic BP (DBP) ,80 mmHg in patients with hypertension and diabetes (9). The guidelines

Cyclo-oxygenase (Cox), a rate-limiting enzyme in the synthesis of prostanoids, is encoded by two genes, Cox-1 and Cox-2, which are differentially expressed and regulated. Human Cox-1 and -2 polypeptides share 61% primary sequence identity. While the expression of Cox-1 is maximal in quiescent cells. Cox-2 expression is induced by growth factors and cytokines. We have screened a human genomic library with a probe from the 5'-untranslated region (UTR) of the human Cox-2 (hCox-2) cDNA and isolated two overlapping genomic clones. We have determined the DNA sequence of 0.8 kb upstream of the transcription start site, 6 kb of protein coding region, which includes 10 exons and 9 introns, as well as 2.5 kb of the 3'-UTR. The structures of the hCox-1 and hCox-2 and the murine TIS10 (Cox-2) genes are highly conserved, with a few exceptions. The 3'-UTRs of the Cox-1 and -2 genes are distinct; for example, the largest exon in the Cox-2 gene encodes the entire 3'-UTR, containing 22 copies of the 'AUUUA' RNA instability element. Sequence analysis of the 5'-flanking region has shown several potential transcription regulatory sequences, including a TATA box, a C/EBP motif, two AP-2 sites, three SP1 sites, two NF-kappa B sites, a CRE motif and an Ets-1 site. These efforts serve as a basis for future studies on transcriptional and post-transcriptional mechanisms of Cox-2 gene regulation.

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HuR is a ubiquitously expressed mRNA-binding protein.Intracellular localization of HuR is predominantly nuclear, but it shuttles between the nucleus and the cytoplasm. In the cytoplasm it can stabilize certain transcripts. Because nucleocytoplasmic translocation of HuR is necessary for its activity, it was hypothesized that cytoplasmic HuR expression in cancer cells could be a prognostic marker. To test the significance of HuR in carcinogenesis of the breast, we have investigated HuR expression in a mouse mammary gland tumor model and from 133 invasive ductal breast carcinoma specimens. HuR expression was elevated in the cyclooxygenase-2 transgene-induced mouse mammary tumors, and its expression was predominantly cytoplasmic in the tumor cells. In the human carcinoma samples, high cytoplasmic immunoreactivity for HuR was found in 29% (38 of 133) of the cases. Cytoplasmic HuR expression associated with high grade (P = 0.0050) and tumor size over 2 cm (P = 0.0082). Five-year distant disease-free survival rate was 42% [95% confidence interval (95% CI), 26-58] in cytoplasm-high category and 84% (95% CI, 76-91) in cytoplasm-negative or -low category (P < < 0.0001), and high cytoplasmic expression of HuR was an independent prognostic factor in a Cox multivariate model (relative risk 2.07; 95% CI, 1.05-4.07). Moreover, high cytoplasmic HuR immunopositivity was significantly associated with poor outcome in the subgroup of node-negative breast cancer in a univariate analysis (P < < 0.0007). Our results show that high cytoplasmic HuR expression is associated with a poor histologic differentiation, large tumor size, and poor survival in ductal breast carcinoma. Thus, HuR is the first mRNA stability protein of which expression associates with poor outcome in breast cancer. (Cancer Res 2005; 65(6): 2157-61)