A critical challenge for chemotherapy is the development of chemoresistance in breast cancer. However, the underlying mechanisms and validated predictors remain unclear. Extracellular vesicles (EVs) have gained attention as potential means for cancer cells to share intracellular contents. In adriamycin-resistant human breast cancer cells (MCF-7/ADM), we analyzed the role of transient receptor potential channel 5 (TrpC5) in EV formation and transfer as well as the diagnostic implications. Up-regulated TrpC5, accumulated in EVs, is responsible for EV formation and trapping of adriamycin (ADM) in EVs. EV-mediated intercellular transfer of TrpC5 allowed recipient cells to acquire TrpC5, consequently stimulating multidrug efflux transporter P-glycoprotein production through a Ca 2+ -and activated T-cells isoform c3-mediated mechanism and thus, conferring chemoresistance on nonresistant cells. TrpC5-containing circulating EVs were detected in nude mice bearing MCF-7/ ADM tumor xenografts, and the level was lower after TrpC5-siRNA treatment. In breast cancer patients who underwent chemotherapy, TrpC5 expression in the tumor was significantly higher in patients with progressive or stable disease than in patients with a partial or complete response. TrpC5-containing circulating EVs were found in peripheral blood from patients who underwent chemotherapy but not patients without chemotherapy. Taken together, we found that TrpC5-containing circulating EVs may transfer chemoresistance property to nonchemoresistant recipient cells. It may be worthwhile to further explore the potential of using TrpC5-containing EVs as a diagnostic biomarker for chemoresistant breast cancer.T he development of chemotherapeutic resistance in breast cancer is a serious problem (1, 2). To date, the mechanisms underlying chemoresistance are still largely unknown, and no validated predictive factor of chemoresistance is available in the clinic. Therefore, it is important to identify the signaling pathways and search for circulating markers in breast cancer resistant to chemotherapy.The extracellular environment contains a large number of mobile membrane-limited vesicles named extracellular vesicles (EVs). Major EV populations include exosomes, microvesicles, and apoptotic bodies (1, 3-5). These dynamic EVs may have essential function in intercellular communication and immune regulation (5). Tumor cells also generate EVs (3, 4). Large quantities of tumor-derived circulating EVs have been found in the blood of patients with glioblastoma multiforme (4), pancreatic cancer (6), gastric cancer (7), and acute myeloid leukemia (8). They contain cell surface proteins, RNA, and DNA (3, 4, 9, 10). They mediate intercellular cross-talk by transferring their intravesicular contents from donor to recipient cells and participating in tumor invasion and metastasis (11-13). However, how these structures are generated and their importance in chemotherapeutic resistance in breast cancer are poorly understood.On the basis of our previous finding that transient receptor...

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Alzheimer's disease (AD) is the most common cause of dementia and cannot be cured. The etiology and pathogenesis of AD is still not fully understood, the genetics is considered to be one of the most important factors for AD onset, and the identified susceptible genes could provide clues to the AD mechanism and also be the potential targets. MicroRNA-146a-5p (miR-146a) is well known in the regulation of the inflammatory response, and the functional SNP of miR-146a was associated with AD risk. In this study, using a noninvasive nasal administration, we discovered that a miR-146a agomir (M146AG) rescued cognitive impairment in the APP/PS1 transgenic mouse and alleviated the overall pathological process in the AD mouse model, including neuroinflammation, glia activation, Ab deposit, and tau phosphorylation in hippocampi. Furthermore, the transcriptional analysis revealed that besides the effect of neuroinflammation, M146AG may serve as a multi-potency target for intervention in AD. In addition, Srsf6 was identified as a target of miR-146a, which may play a role in AD progression. In conclusion, our study supports that the nasal-to-brain pathway is efficient and operable for the brain administration of microRNAs (miRNAs), and that miR-146a may be a new potential target for AD treatment.

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Serum C-reactive protein (CRP), a sensitive marker of systemic inflammation, has been reported to be associated with the risk of a number of cancers including breast cancer. However, the results are inconsistent. To investigate the association between serum CRP levels and early breast cancer, we conducted a hospital-based case-control study among 506 newly diagnosed breast cancer patients and 506 controls with benign breast diseases matched by age and menopausal status. Odds ratios (ORs) were computed with unconditional logistic regression models, adjusted for major confounding factors. Relative to women with the lowest quartile of CRP level, women with the highest quartile had 1.65-fold increased breast cancer risk (OR: 1.65, 95% CI: 1.12-2.42) in a significant dose-response manner (p(trend) = .011). Stratification analysis revealed a positive association only for overweight postmenopausal women (highest CRP quartile versus lowest CRP quartile: OR: 2.78, 95% CI: 1.18-6.6). Multinominal logistic regression analysis showed that only hormonal receptor (HR) positive and human epidemiological receptor 2 (HER2) negative breast cancers had elevated serum CRP levels. We observed that elevated serum CRP levels are positively associated with early breast cancer, predominantly among overweight and postmenopausal women. This study provided epidemiological evidence that chronic inflammation might mediate the association between obesity and postmenopausal breast cancer. Although a positive association between serum CRP and HR positive/HER2 negative breast cancer is intriguing, further epidemiological studies are needed to confirm such findings.