Identification of potential miRNA biomarkers for traumatic osteonecrosis of femoral head

Traumatic osteonecrosis of femoral head (TONFH) is a common orthopedic disease caused by physical injury in hip. However, the unclear pathogenesis mechanism of TONFH and lacking of simple noninvasive early diagnosis method cause the necessity of hip replacement for most patients with TONFH. In this study, we aimed to identify circulating microRNAs (miRNAs) by integrated bioinformatics analyses as potential biomarker of TONFH. mRNA expression profiles were downloaded from the Gene Expression Omnibus database. Then we combined two miRNA screen methods: Weighted gene co-expression network analysis and fold change based differentially expressed miRNAs analysis. As a result, we identified 14 key miRNAs as potential biomarkers for TONFH. Besides, 302 target genes of these miRNAs were obtained and the miRNA–mRNA interaction network was constructed. Furthermore, the results of Kyoto Encyclopedia of Gene and Genome pathway analysis, Gene Ontology function analysis, protein–protein interaction (PPI) network analysis and PPI network module analysis showed close correlation between these 14 key miRNAs and TONFH. Then we established receiver operating characteristic curves and identified 6-miRNA signature with highly diagnosis value including miR-93-5p (area under the curve [AUC] = 0.93), miR-1324 (AUC = 0.92), miR-4666a-3p (AUC = 0.92), miR-5011-3p (AUC = 0.92), and miR-320a (AUC = 0.89), miR-185-5p (AUC = 0.89). Finally, the results of quantitative real-time polymerase chain reaction confirmed the significantly higher expression of miR-93-5p and miR-320a in the serum of patients with ONFH. These circulating miRNAs could serve as candidate early diagnosis markers and potential treatment targets of TONFH.     

SOX2-induced upregulation of lncRNA LINC01561 promotes non-small-cell lung carcinoma progression by sponging miR-760 to modulate SHCBP1 expression

Long noncoding RNAs (lncRNAs) have been shown to have critical regulatory roles in tumorigenesis. lncRNA LINC01561 (LINC01561) is a newly identified tumor-related lncRNA and its dysregulation has been demonstrated in several tumors. However, whether LINC01561 is involved in the progression of non-small-cell lung carcinoma (NSCLC) and its underlying mechanisms remain unknown. In this study, we first provided evidence that LINC01561 expressions were distinctly upregulated in NSCLC tissues and cell lines. Combining with bioinformatics assays and mechanism experiments, our group demonstrated that LINC01561 was activated by SOX2 in NSCLC. Clinical research revealed that upregulation of LINC01561 was related to poorer clinicopathologic features and shorter survival time. Functionally, suppression of LINC01561 exhibited tumor-suppressive functions through impairing cell proliferation, migration, and invasion as well as inducing apoptosis. Moreover, we verified that LINC01561 could directly bind to miR-760, isolating miR-760 from its target gene SHC SH2 domain-binding protein 1 (SHCBP1). We also found that SHCBP1 was lowly expressed in NSCLC and served as a tumor promoter. A functional study indicated that LINC01561 regulated SHCBP1 expression by competitively binding to miR-760. In summary, our findings indicated that SOX2-induced overexpression of LINC01561 promoted the proliferation and metastasis by acting as a competing endogenous RNA to modulate SHCBP1 by sponging miR-760.     

The correlation between CT features and insulin resistance levels in patients with T2DM complicated with primary pulmonary tuberculosis

The aim is to investigate the correlation between computed tomography (CT) features and insulin resistance levels in patients with type 2 diabetes mellitus (T2DM) complicated with primary pulmonary tuberculosis (PTB). Nearly, 268 untreated PTB patients complicated with T2DM were divided into two groups according to the optimal cutoff value of HOMA-IR score for the Chinese population: HOMA-IR ≤ 2.69 (Group I: 74 patients), >2.69 (Group II: 194 patients). The basic characteristics and changes of CT manifestations were analyzed. In the two groups, the detection rate of large segmented leafy shadow was 39.2% and 78.9%; the air bronchogram sign detection rate was 40.5% and 80.9%; the discovery rate of mouth-eaten cavity was 33.8% and 73.7%; the thin-walled cavity detection rate was 2.7% and 16.0%; the rate of multiple cavities was 35.1% and 69.6%; and bronchial tuberculosis was found in 4.1% and 35.6%, respectively. The detection rates of lesions in Group II were significantly higher than in Group I (p < .05). HOMA-IR was found independently associated with large segmented leafy shadow, air bronchial sign, thin-walled cavity, and bronchial tuberculosis. The level of insulin resistance can effectively reflect the severity of PTB patients with T2DM. CT scan can directly provide image information in clinics. These two examinations can guide clinicians to accurately formulate subsequent treatment plans.     

Probiotic Bacillus amyloliquefaciens mediate M1 macrophage polarization in mouse bone marrow-derived macrophages

Depending on the microenvironment, macrophages can acquire distinct functional phenotypes, referred to as classically activated M1 and M2. M1 macrophages are considered potent effector cells that kill intracellular pathogens, and M2 macrophages promote the resolution of wound healing. In this study, we are interested to know whether probiotic Bacillus amyloliquefaciens (Ba) can induce macrophages polarization. Real-time fluorescence PCR analysis demonstrated that the expression of IL-1β, iNOS, TNF-α and IL-6 genes for M1 macrophages was significantly increased at 1.5 h after probiotic Ba treatment compared to the probiotic Ba-free treatment (P < 0.01), whereas the expression of M2 macrophage marker genes (Arg1, Fizz1, MR, Ym1) was decreased (P < 0.05). Furthermore, the phagocytic activity was dramatically increased in the Ba-treated BMDMs using a FITC-dextran endocytosis assay. Together, these findings indicated that probiotic Ba facilitated polarization of M1 macrophages and enhanced its phagocytic capacity. The results expanded our knowledge about probiotic function-involved macrophage polarization.     

Both mature miR-17-5p and passenger strand miR-17-3p target TIMP3 and induce prostate tumor growth and invasion

MicroRNAs (miRNA) precursor (pre-miRNA) molecules can be processed to release a miRNA/miRNA* duplex. In the canonical model of miRNA biogenesis, one strand of the duplex is thought to be the biologically active miRNA, whereas the other strand is thought to be inactive and degraded as a carrier or passenger strand called miRNA* (miRNA star). However, recent studies have revealed that miRNA* strands frequently play roles in the regulatory networks of miRNA target molecules. Our recent study indicated that miR-17 transgenic mice could abundantly express both the mature miR-17-5p and the passenger strand miR-17-3p. Here, we showed that miR-17 enhanced prostate tumor growth and invasion by increasing tumor cell proliferation, colony formation, cell survival and invasion. miRNA target analysis showed that both miR-17-5p and miR-17-3p repressed TIMP metallopeptidase inhibitor 3 (TIMP3) expression. Silencing with small interfering RNA against TIMP3 promoted cell survival and invasion. Ectopic expression of TIMP3 decreased cell invasion and cell survival. Our results demonstrated that mature miRNA can function coordinately with its passenger strand, enhancing the repressive ability of a miRNA by binding the same target. Within an intricate regulatory network, this may be among the mechanisms by which miRNA can augment their regulatory capacity.     

Ribosomal protein S7 regulates arsenite-induced GADD45α expression by attenuating MDM2-mediated GADD45α ubiquitination and degradation

The stress-responding protein, GADD45α, plays important roles in cell cycle checkpoint, DNA repair and apoptosis. In our recent study, we demonstrate that GADD45α undergoes a dynamic ubiquitination and degradation in vivo, which process can be blocked by the cytotoxic reagent, arsenite, resulting in GADD45α accumulation to activate JNKs cell death pathway, thereby revealing a novel mechanism for the cellular GADD45α functional regulation. But the factors involved in GADD45α stability modulations are unidentified. Here, we demonstrated that MDM2 was an E3 ubiquitin ligase for GADD45α. One of MDM2-binding partner, ribosomal protein S7, interacted with and stabilized GADD45α through preventing the ubiquitination and degradation of GADD45α mediated by MDM2. This novel function of S7 is unrelated to p53 but seems to depend on S7/MDM2 interaction, for the S7 mutant lacking MDM2-binding ability lost its function to stabilize GADD45α. Further investigations indicated that arsenite treatment enhanced S7–MDM2 interaction, resulting in attenuation of MDM2-dependent GADD45α ubiquitination and degradation, thereby leading to GADD45α-dependent cell death pathway activation. Silencing S7 expression suppressed GADD45α-dependent cytotoxicity induced by arsenite. Our findings thus identify a novel function of S7 in control of GADD45α stabilization under both basal and stress conditions and its significance in mediating arsenite-induced cellular stress.