Ovarian cancer (OVCa) stem cells are associated with tumor growth, metastasis, and recurrence, which are driving forces behind a majority of the OVCa-related mortality. This subpopulation of cancer cells are characterized by uncontrolled proliferation, high invasiveness, and resistance against the current platinum-based therapy. Thus, targeting OVCa cancer stem cells has been focused in recent therapeutic development. Isolation and purification of cancer stem cells are, however, challenging for the lack of sensitive and specific markers. In this study, we demonstrated that miR-551b was upregulated in OVCa stem cells, by using a quantitative PCR array, correlating with the pathological grades of this malignancy. In vitro experiments indicated that miR-551b promoted the proliferation, invasion, and chemoresistance of OVCa cells and cancer stem cells. Further analysis suggested that miR-551b functioned through the suppression of Foxo3 and TRIM31, two important tumor suppressors. In support of this, our in vivo experiments using mouse xenograft models showed that inhibiting miR-551b significantly increased the susceptibility of OVCa cells to cisplatin and prolonged the survival of the host mice. In conclusion, our study suggested miR-551b as a potential biomarker for OVCa stem cells and explored its functional mechanism, providing a potential therapeutic target for future drug development.Electronic supplementary materialThe online version of this article (doi:10.1007/s12032-016-0842-9) contains supplementary material, which is available to authorized users.

CXCL3 belongs to the CXC-type chemokine family and is known to play a multifaceted role in various human malignancies. While its clinical significance and mechanisms of action in uterine cervical cancer (UCC) remain unclear. This investigation demonstrated that the UCC cell line HeLa expressed CXCL3, and strong expression of CXCL3 was detected in UCC tissues relative to nontumor tissues. In addition, CXCL3 expression was strongly correlated with CXCL5 expression in UCC tissues. In vitro, HeLa cells overexpressing CXCL3, HeLa cells treated with exogenous CXCL3 or treated with conditioned medium from WPMY cells overexpressing CXCL3, exhibited enhanced proliferation and migration activities. In agreement with these findings, CXCL3 overexpression was also associated with the generation of HeLa cell tumor xenografts in athymic nude mice. Subsequent mechanistic studies demonstrated that CXCL3 overexpressing influenced the expression of extracellular signal-regulated kinase (ERK) signaling pathway associated genes, including ERK1/2, Bcl-2, and Bax, whereas the CXCL3-induced proliferation and migration effects were attenuated by exogenous administration of the ERK1/2 blocker PD98059. The data of the current investigation support that CXCL3 appears to hold promise as a potential tumor marker and interference target for UCC. K E Y W O R D Scervical cancer, CXCL3, ERK, malignant behavior, upregulation

Organic light-emitting diodes (OLEDs), which have been recently utilized in some flat-panel display screens such as mobile phones and televisions, show many merits, including light weight, high flexibility, energy preservation, and so forth, and are considered the next-generation displays and solid-state lightings. Blue-emitting materials that can be applied in nondoped OLEDs with little efficiency roll-offs at high brightness are of great importance. Here, a highly efficient, blue-emitting material, 9-phenyl-10-(4-(pyren-1-yl)phenyl)-9H-pyreno [4,5-d]imidazole (PyPI-Py), is achieved using pyrene [4,5-d]imidazole and pyrene as the weak electron donor and electron acceptor, respectively. The nondoped blue OLED exhibits excellent performance with a maximum brightness of 75,687 cd m −2 , a maximum current efficiency of 13.38 cd A −1 , and a maximum external quantum efficiency (η ext ) of 8.52%. Moreover, the η ext is maintained at 8.35% and 8.05% at a brightness of 10,000 and 50,000 cd m −2 , respectively, displaying extremely small efficiency roll-offs of 2.0% and 5.5%.The device characteristics are among the highest values for nondoped blue OLEDs and correspond to the best performance obtained for nondoped pyrene-based blue OLEDs. The superior performance is attributed to the proper donor-acceptor design strategy which results in a quasi-equivalent hybrid local and charge-transfer excited state with the maximum generation of an 82% fraction of singlet excitons.

A nondoped device based on the PIAnTAZ emitter shows blue electroluminescence with a maximum EQE of 7.96%, a maximum luminance of 58 675 cd m−2 and negligible efficiency roll-offs.