No abstract

Profilin1, a ubiquitously expressed actin-binding protein, plays a critical role in cell migration through actin cytoskeletal regulation. Given the traditional view of profilin1 as a promigratory molecule, it is difficult to reconcile observations that profilin1 is down-regulated in various invasive adenocarcinomas and that reduced profilin1 expression actually confers increased motility to certain adenocarcinoma cells. In this study, we show that profilin1 negatively regulates lamellipodin targeting to the leading edge in MDA-MB-231 breast cancer cells and normal cells; profilin1 depletion increases lamellipodin concentration at the lamellipodial tip (where it binds Ena/VASP), and this mediates the hypermotility. We report that the molecular mechanism underlying profilin1's modulation of lamellipodin localization relates to phosphoinositide control. Specifically, we show that phosphoinositide binding of profilin1 inhibits the motility of MDA-MB-231 cells by negatively regulating PI(3,4)P 2 at the membrane and thereby limiting recruitment of lamellipodin [a PI(3,4)P 2 -binding protein] and Ena/ VASP to the leading edge. In summary, this study uncovers a unique biological consequence of profilin1-phosphoinositide interaction, thus providing direct evidence of profilin1's regulation of cell migration independent of its actin-related activity.T he ubiquitously expressed cytoskeleton-modulating protein profilin1 influences multiple processes involved in cell motility, making it a challenge to elucidate the exact molecular mechanism that controls migration. At least one major function of profilin1 is to regulate actin polymerization. Profilin1 regenerates actin monomers from disassembling filament networks by facilitating the exchange of ATP for ADP on G-actin. By further inhibiting spontaneous nucleation of G-actin, profilin1 causes an accumulation of profilin1/ATP-G-actin pool available for polymerization. Because profilin1 also has an affinity for poly-Lproline sequences, it binds to almost all major actin nucleating and F-actin elongating proteins that contain proline-rich domains [e.g., N-WASP (neuronal Wiskott-Aldrich syndrome protein), Ena (enabled)/VASP (vasodilator stimulated phosphoprotein), and formins], and this allows profilin1-mediated recruitment of ATP-G-actin to these proteins, enhancing actin polymerization (1, 2). In addition, profilin1 binds to plasma membrane presumably through its interactions with various phosphoinositides (3). Profilin1 binds to phosphatidylinositol-4,5-bisphosphate [PI(4,5)P 2 ], phosphatidylinositol-3,4-bisphosphate [PI(3,4)P 2 ], and phosphatidylinositol-3,4,5-triphosphate [PI(3,4,5) P 3 ]), at least in vitro (4). Based on PI(4,5)P 2 binding, it has been proposed that the phosphoinositide binding site of profilin1 overlaps with its actin-binding site (5), and to some extent spans a second region neighboring the polyproline binding site (6). This has prompted speculation that the major role of phosphoinositide binding of profilin1 would be to inhibit its interaction with act...

Nowadays, depression is the world's major health concern and economic burden worldwide. However, due to the limitations of current methods for depression diagnosis, a pervasive and objective approach is essential. In the present study, a psychophysiological database, containing 213 (92 depressed patients and 121 normal controls) subjects, was constructed. The electroencephalogram (EEG) signals of all participants under resting state and sound stimulation were collected using a pervasive prefrontal-lobe threeelectrode EEG system at Fp1, Fp2, and Fpz electrode sites. After denoising using the Finite Impulse Response filter combining the Kalman derivation formula, Discrete Wavelet Transformation, and an Adaptive Predictor Filter, a total of 270 linear and nonlinear features were extracted. Then, the minimal-redundancy-maximal-relevance feature selection technique reduced the dimensionality of the feature space. Four classification methods (Support Vector Machine, K-Nearest Neighbor, Classification Trees, and Artificial Neural Network) distinguished the depressed participants from normal controls. The classifiers' performances were evaluated using 10-fold cross-validation. The results showed that K-Nearest Neighbor (KNN) had the highest accuracy of 79.27%. The result also suggested that the absolute power of the theta wave might be a valid characteristic for discriminating depression. This study proves the feasibility of a pervasive three-electrode EEG acquisition system for depression diagnosis.

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related mortality in the world. Late diagnosis is one of the most significant reasons for the high mortality rate of lung cancer. The identification of microRNAs (miRNAs) has opened a new field for molecular diagnosis of cancer. The purpose of the present study was to investigate whether plasma miRNAs may be used as biomarkers for early-stage NSCLC. A total of 232 participants, including 149 NSCLC patients and 83 healthy controls, were recruited between July 2012 and May 2014. We measured the levels of 10 miRNAs (miR-30d, miR-383, miR-20a, miR-145, miR-221, miR-25, miR-223, miR-21, miR-126 and miR-210) in plasma samples of 40 individuals (20 patients and 20 matched healthy controls) at the point of identification of disease, and 129 NSCLC patients and 83 healthy controls at the validation stage using reverse transcription-quantitative polymerase chain reaction. Receiver operating characteristics (ROC) curves were generated for each possible combination of the miRNAs. We observed that the expression of plasma miR-145, miR-20a, miR-21 and miR-223 was significantly increased in the early-stage NSCLC samples compared with controls. miRNAs have significant diagnostic value for early-stage NSCLC. Combined ROC analyses using these four miRNAs revealed an elevated area under the ROC curve (AUC) of 0.897, with a sensitivity and specificity of 81.8 and 90.1%, respectively. This AUC helped in distinguishing early-stage NSCLC. Furthermore, the levels of the four plasma miRNAs were significantly decreased following surgery (P<0.05). Altered expression of miR-145, miR-20a, miR-21 and miR-223 in plasma are of tumor origin, and the four miRNAs may represent potential novel non-invasive biomarkers for early-stage NSCLC.

We previously showed that silencing profilin-1 (Pfn1) expression increases breast cancer cell motility, but the underlying mechanisms have not been explored. Herein, we demonstrate that loss of Pfn1 expression leads to slower but more stable lamellipodial protrusion thereby enhancing the net protrusion rate and the overall motility of MDA-MB-231 breast cancer cells. Interestingly, MDA-MB-231 cells showed dramatic enrichment of VASP at their leading edge when Pfn1 expression was downregulated and this observation was also reproducible in other cell types including human mammary epithelial cells and vascular endothelial cells. We further demonstrate that Pfn1 downregulation results in a hyper-motile phenotype of MDA-MB-231 cells in an Ena/ VASP-dependent mechanism. Pfn1-depleted cells display a strong colocalization of VASP with lamellipodin (Lpd-a PI(3,4)P 2 -binding protein that has been previously implicated in lamellipodial targeting of Ena/VASP) at the leading edge. Finally, inhibition of PI3-kinase (important for generation of PI(3,4)P 2 ) delocalizes VASP from the leading edge. This observation is consistent with a possible involvement of Lpd in enhanced membrane recruitment of VASP that results from loss of Pfn1 expression. Our findings for the first time highlight a possible mechanism of how reduced expression of a pro-migratory molecule like Pfn1 could actually promote motility of breast cancer cells.Disruption of the actin cytoskeleton is a feature of malignant cells that correlates with dysregulated expression of various actin-binding proteins (ABPs) (Wang et al., 1996;Clark et al., 2000). The malignant phenotype of tumor cells often can be reversed by experimental restoration of ABP expression, suggesting misregulation of ABPs could contribute directly to malignancy (Tanaka et al., 1995;Nikolopoulos et al., 2000). Profilin-1 (Pfn1), a ubiquitously expressed G-actin binding protein, is significantly downregulated in various types of adenocarcinoma (breast, pancreatic, hepatic) (Janke et al., 2000;Gronborg et al., 2006;Wu et al., 2006). This raises a fundamental question as to whether loss of Pfn1 expression contributes to malignant progression of tumor cells. We found that upon downregulation of Pfn1, normal human mammary epithelial cells (HMEC) exhibit disruption of cell-cell adhesion (a hallmark change that facilitates epithelial cell dissemination and migration during cancer progression) (Zou et al., 2007). Furthermore, * Correspondence to: Partha Roy, Department of Bioengineering, University of Pittsburgh, 306 Center for Bioengineering, 300 Technology Drive, Pittsburgh, PA 15219. par19@pitt.edu. Additional Supporting Information may be found in the online version of this article. NIH Public AccessAuthor Manuscript J Cell Physiol. Author manuscript; available in PMC 2010 November 24. NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author Manuscript silencing Pfn1 expression leads to increased motility and invasiveness of breast cancer cell lines and conversely, overexpression of Pfn...

No abstract

As natural experiments, famines provide a unique opportunity to test the health consequences of nutritional deprivation during the critical period of early life. Using data on 4,972 Chinese born between 1956 and 1963 who participated in a large mental health epidemiology survey conducted between 2001 and 2005, we investigated the potential impact of famine exposure in utero and during the early postnatal life on adult mental illness. The risk of mental illness was assessed with the 12-item General Health Questionnaire (GHQ-12) and eight other risk factors, and the famine impact on adult mental illness was estimated by difference-in-difference models. Results show that compared with women born in 1963, women born during the famine years (1959–1961) had higher GHQ scores (increased by 0.95 points; CI: 0.26, 1.65) and increased risk of mental illness (OR= 2.80; CI: 1.23, 6.39); those born in 1959 were the most affected and had GHQ scores 1.52 points higher (CI: 0.42, 2.63) and an OR for mental illness of 4.99 (CI: 1.68, 14.84). Compared to men in the 1963 birth cohort, men born during the famine had lower GHQ scores (decreased by 0.89 points; CI: −1.59, −0.20) and a nonsignificant decrease in the risk of mental illness (OR = 0.60; CI: 0.26, 1.40). We speculate that the long-term consequences of early-life famine exposure include both the selection of the hardiest and the enduring deleterious effects of famine on those who survive. The greater biological vulnerability and stronger natural selection in utero of male versus female fetuses during severe famine may result in a stronger selection effect among men than women, obscuring the deleterious impact of famine exposure on the risk of mental illness in men later in life.

Tibial dyschondroplasia (TD) is an important long bone defect of broiler chickens that disturbs the proximal growth plate and is characterized by non-vascularized cartilage, a distended growth plate and lameness. Celastrol, a medicinal root extract from the plant Tripterygium wilfordii, is reported widely as a well-known heat-shock protein 90 (Hsp90) inhibitor. Recently, Hsp90 inhibition in chondrocyte differentiation and growth-plate vascularization were effective in restoring the morphology of the growth plate. The present study was aimed at investigating Hsp90 inhibition in TD using celastrol. The broiler chicks were divided into three groups; Control; TD induced (40 mg/kg thiram) and celastrol treatment. Hsp90, vascular endothelial growth factor and Flk-1 expressions were evaluated by quantitative real-time polymerase chain reaction and the protein levels of Hsp90 were measured by Western blot analysis. Antioxidant enzymes were determined to assess the liver damage caused by thiram and the protective effects of the medicine were evaluated by levels of serum biomarkers. The expression levels of Hsp90 and vascular endothelial growth factor mRNA transcripts were increased while Flk-1 receptor was decreased in TD-affected chicks. Celastrol therapy inhibited Hsp90 mRNA and protein levels and up-regulated the expressions of receptor Flk-1 in TD-affected tibial growth plates significantly (P< 0.05) in addition to rectifying the damaging effects of thiram on the liver by decreasing the levels of aspartate aminotransferase, alanine aminotransferase and malondialdehyde and correcting the oxidative imbalance. In conclusion, administering celastrol to dyschondroplastic chicks prevented un-vascularized growth plate, lameness and reinstated angiogenesis. Celastrol may be efficacious for the treatment of TD through the inhibition of Hsp90 expression and limiting the liver damage caused by thiram in broiler chickens.