Structure-Based Identification, Characterization, and Disruption of Human Securin-Binding SH3 Domains in Lung Cancer.

The human securin is an oncogenic transcription factor that has been found to promote migration and invasion of lung cancer and many other tumors. The protein contains a PxxP motif that can be recognized and bound by diverse cellular partners via Src homology (SH3) domain to regulate biological and pathological events. The motif is covered by a decapeptide segment (161)LGPPSPVKMP(170) (SecPeptide) as the potential binding site of SH3 domains. Here, we attempted to systemically identify the SH3 binding partners of human securin in lung cancer and to characterize the intermolecular interaction between SecPeptide and the identified SH3 domains. A bioinformatics protocol that integrated literature curation, complex structural modeling, and binding affinity analysis was described to perform systematic search against an array of SH3-containing proteins involved in lung cancer signaling pathway and, consequently, three putative domains, namely GRB2, CRK, and RasGAP, were identified that have high potential to recognize and bind SecPeptide. The molecular mechanism and biological implication underlying the intermolecular interaction between these domains and SecPetide were investigated at structural and energetic level. Surface plasmon resonance assay revealed a high or moderate affinity of SecPeptide and its two mutants binding to CRK-SH3 domain with dissociation constants Kd = 79.8, 24.2, and 64.6 µM, respectively.

Serum IL-17 & eotaxin levels in asthmatic patients with allergic rhinitis.

OBJECTIVE: To investigate the serum levels of Interleukin (IL)-17 and eotaxin levels and the relationship between serum IL-17, eotaxin and pulmonary function in asthmatic patients with allergic rhinitis. METHODS: Serum IL-17 and eotaxin levels in asthmatic patients with allergic rhinitis during attacking and remission and in healthy control subjects were measured using enzyme-linked immunosorbent assay (ELISA) kits. Then we studied the correlation between the serum IL-17, eotaxin levels and pulmonary function in patients. RESULTS: Serum IL-17 and eotaxin levels were significantly elevated in patients during asthma attack and remission compared with healthy control subjects. These levels in patients during asthma attack were much higher than those during remission. Furthermore, serum IL-17 and eotaxin levels were negatively correlated with pulmonary function in asthmatic patients with allergic rhinitis, respectively. CONCLUSION: Our findings suggest that IL-17 and eotaxin are important factors in asthma with allergic rhinitis, and the correlation between serum IL-17, eotaxin and lung function possibly lead to improvements in the diagnosis and treatment of asthma with allergic rhinitis and related diseases.

The expression and function of microRNA-203 in lung cancer.

We aimed to determine the expression of microRNA-203 (miR-203) in human lung cancer cell lines and to evaluate the effects of miR-203 by targeting survivin, on the lung cancer cell line 95-D to provide potential new strategies for treating lung cancer. The expression of miR-203 was detected using quantitative real-time PCR (qRT-PCR) in the in vitro cultured lung cancer cells A549, HCC827, NCI-H1299, and 95-D as well as in normal human bronchial epithelial cells. Following a 72-h transfection with the miR-203 precursor in 95-D lung cancer cells, the change in miR-203 expression was detected using qRT-PCR and the resulting effect on survivin protein expression was ascertained by Western blot analysis. The influence of miR-203 on the viability of 95-D lung cancer cells was evaluated using 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. The effect of miR-203 on 95-D cell proliferation was analyzed using flow cytometry. The consequences of miR-203 expression on 95-D cell apoptosis were analyzed by Annexin V/propidium iodide double staining coupled with flow cytometry. The role of miR-203 in the invasive potential of 95-D cells was studied using a transwell chamber assay. A luciferase reporter gene system was used to verify that survivin is a target gene for miR-203. By qRT-PCR, the expression of miR-203 was lower in lung cancer cells than in normal bronchial epithelial cells (p < 0.01), and the expression of miR-203 in 95-D lung cancer cells was significantly higher after a 72-h transfection with the miR-203 precursor (p < 0.01). After a 72-h transfection with the miR-203 precursor, survivin protein levels in 95-D cells were significantly decreased (p < 0.01). Cell viability, as assessed with an MTT assay, decreased following an increase in miR-203 expression (p < 0.05). The flow cytometry results indicated that after miR-203 expression increased, the cell proliferation index decreased (p < 0.05) and the number of apoptotic cells increased (p < 0.01). Increased miR-203 expression led to a significant decrease in the number of cells that migrated through a transwell chamber membrane (p < 0.01). The luciferase reporter gene system demonstrated that the relative luciferase activity significantly decreased after transfection with the miR-203 precursor (p < 0.05). The expression of miR-203 is downregulated in lung cancer cells. miR-203 negatively regulates survivin protein expression and inhibits the proliferation and invasion of lung cancer cells. Therapeutic strategies that enhance miR-203 expression or silence survivin could potentially benefit lung cancer patients.

The association between albumin and C-reactive protein in older adults.

Albumin had been found to be a marker of inflammation. The purpose of our study was to investigate the relationship between albumin and C-reactive protein (CRP) in 3579 participants aged 60 to 80 years from the National Health and Nutrition Examination Survey (NHANES). In order to evaluate the association between albumin and CRP, We downloaded the analyzed data (2015-2018) from the NHANES in the United States, and the age of study population was limited to 60 to 80 years (n = 4051). After exclusion of subjects with missing albumin (n = 456) and CRP (n = 16) data, 3579 subjects aged 60 to 80 years were reserved for a cross-sectional study. All measures were calculated accounting for NHANES sample weights. We used the weighted χ2 test for categorical variables and the weighted linear regression model for continuous variables to calculate the difference among each group. The subgroup analysis was evaluated through stratified multivariable linear regression models. Fitting smooth curves and generalized additive models were also carried out. We found albumin negatively correlated with CRP after adjusting for other confounders in model 3 (ß = -0.37, 95% CI: -0.45, -0.28, P < .0001). After converting albumin from a continuous variable to a categorical variable (quartiles), albumin level was also negatively associated with serum CRP in all groups (P for trend < .001 for each). In the subgroup analysis stratified by gender, race/ethnicity, smoking, high blood pressure, the negative correlation of albumin with CRP was remained. We also found that the level of CRP further decreased in other race (OR: -0.72, 95% CI: -0.96, -0.47 P < .0001) and participants with smoking (OR: -0.61, 95% CI: -0.86, -0.36 P < .0001). Our findings revealed that albumin levels was negatively associated with CRP levels among in USA elderly. Besides, CRP level decreased faster with increasing albumin level in other race and participants with smoking. Considering this association, hypoalbuminemia could provide a potential predictive biomarker for inflammation. Therefore, studying the relationship between albumin and CRP can provide a screening tool for inflammation to guide therapeutic intervention and avoid excessive correction of patients with inflammation.

miR-671-5p inhibits gastric cancer cell proliferation and promotes cell apoptosis by targeting URGCP.

Various studies have demonstrated that microRNA (miRNA) serves an important role in the development of gastric cancer. However, the expression level, clinical significance and the biological function of miRNA in gastric cancer remain largely unknown. The present study investigated the exact roles of miR-671-5p in gastric cancer, confirmed its target and explored its mechanism. Initially, the low expression levels of miR-671-5p in gastric cancer cells were confirmed by reverse transcription-quantitative polymerase chain reaction. TargetScan and MiRanda databases were utilized to forecast the target genes of miR-671-5p, and the prediction was verified by dual-luciferase reporter assay and western blot analysis. Cell Counting Kit-8 was used for cell proliferation detection. An annexin V-fluorescein isothiocyanate kit was used for cell apoptosis determination. Western blot analysis was adopted to measure the protein expression levels in different groups. The results of the present study revealed that there were lower expression levels of miR-671-5p in gastric cancer cells than in normal gastric cells. Upregulator of cell proliferation (URGCP) is a direct target of miR-671-5p and it may be negatively regulated by miR-671-5p. miR-671-5p mimics induced reduction of MKN28 cell proliferation. miR-671-5p mimics caused upregulation of MKN28 cell apoptosis. In addition, western blotting results indicated that the ratio of B-cell lymphoma 2 (Bcl-2)/Bcl-2-associated X protein was significantly decreased in the miR-671-5p mimic group compared with the negative control group (P<0.01). These results suggested that miR-671-5p had a protective role in gastric cancer through inhibiting gastric cancer cell proliferation and promoting cell apoptosis by targeting URGCP. Therefore, miR-671-5p may be an effective therapeutic target for gastric cancer.

microRNA-449a suppresses non-small cell lung cancer.

This study was set to determine the expression of microRNA-449a in cancer tissue and serum of non-small cell lung cancer (NSCLC) patients and explore the underlying mechanisms of its tumor suppressor functions. We selected 50 NSCLC patients in our hospital as the lung cancer group and 50 healthy volunteers as the control group. RT-PCR was performed to detect the expression levels of microRNA-449a in NSCLC tissue and the plasma of NSCLC patients. Further, we transfected microRNA-449a mimic and inhibitor in lung cancer cell line A549, and used western blot to determine the expression level of apoptosis-related molecules Bcl-2 and p53. Compared with the surrounding tissue, microRNA-449a exhibited significantly reduced mRNA expression, which was statistically different (P < 0.05). microRNA-449a exhibited significantly lower expression in NSCLC patients' plasma than the healthy volunteers, which was statistically different (P < 0.05). Spearman correlation analysis showed that microRNA-449a expression levels in NSCLC tissue and plasma of NSCLC patients were reversely correlated with lung cancer differentiation (P < 0.05). But microRNA-449a expression in the surrounding tissue was not significantly correlated with lung cancer differentiation (P > 0.05). Compared with negative control, cell proliferation and p53 and Bcl-2 expression significantly decreased after microRNA-449a mimic transfection (P < 0.05). However, after transfection of microRNA-449a inhibitor, cell proliferation and p53 and Bcl-2 expression significantly increased after microRNA-449a mimic transfection (P < 0.05). microRNA-449a expression levels in NSCLC are significantly lower than those in the surrounding tissue, and its expression levels in NSCLC patients are also lower than those in healthy volunteers. The tumor suppression role of microRNA-449a could be due to its promotion of tumor cell proliferation and its inhibition of tumor cell apoptosis.