miR-181b promotes angiogenesis and neurological function recovery after ischemic stroke.

Promotion of new blood vessel formation is a new strategy for treating ischemic stroke. Non-coding miRNAs have been recently considered potential therapeutic targets for ischemic stroke. miR-181b has been shown to promote angiogenesis in hypoxia and traumatic brain injury model, while its effect on ischemic stroke remains elusive. In this study, we found that overexpression of miR-181b in brain microvascular endothelial cells subjected to oxygen-glucose deprivation in vitro restored cell proliferation and enhanced angiogenesis. In rat models of focal cerebral ischemia, overexpression of miR-181b reduced infarction volume, promoted angiogenesis in ischemic penumbra, and improved neurological function. We further investigated the molecular mechanism by which miR-181b participates in angiogenesis after ischemic stroke and found that miR-181b directly bound to the 3'-UTR of phosphatase and tensin homolog (PTEN) mRNA to induce PTEN downregulation, leading to activation of the protein kinase B (Akt) pathway, upregulated expression of vascular endothelial growth factors, down-regulated expression of endostatin, and promoted angiogenesis. Taken together, these results indicate that exogenous miR-181b exhibits neuroprotective effects on ischemic stroke through activating the PTEN/Akt signal pathway and promoting angiogenesis.

The accuracy of magnetic resonance imaging for preoperative deep myometrium assessment in endometrial cancer.

OBJECTIVE: To evaluate the accuracy of preoperative magnetic resonance imaging (MRI) to detect deep myometrial invasion in patients with endometrial cancer. MATERIALS AND METHODS: We retrospectively reviewed 66 cases of women with endometrial cancer, who underwent preoperative MRI assessment and surgical staging between January 2006 and October 2010. The MRI findings were then compared with the pathology results. The diagnostic accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of MRI in detecting deep myometrium invasion were evaluated. RESULTS: The sensitivity, specificity, accuracy, PPV, and NPV results of MRI for the detection of deep myometrium invasion were 92.52%, 74.35%, 81.81%,71.42%, and 93.54%, respectively, with a kappa of 0.64. In the postmenopausal group, the values were 100%, 55.5%, 74.19%, 61.9%, and 100%. In the premenopausal women, they improved to 85.7%, 90.47%, 88.57%, 88.71%, and 90.47%. The sensitivity (100%) was better than the specificity (55.56%) in the postmenopausal women. The predictive value was markedly higher in the premenopausal women than the postmenopausal women (85.7% vs. 61.9%). CONCLUSION: In patients with endometrial cancer, a preoperative MRI contributes to accurate staging, allowing planning for the scale of surgery and preoperative counseling. In our study, the pretreatment identification of myometrium invasion provided the opportunity for small-scale surgery in the premenopausal women with early endometrial cancer. However, for the postmenopausal patients, the standard surgical procedure is indicated even if the degree of myometrium invasion is low.