Osteosarcoma (OS) is the most common primary malignant bone tumor. Recently, increasing evidence has shown that the long noncoding RNA (lncRNA) DLX6-AS1 (distal-less homeobox 6 antisense 1) plays significant roles in various types of cancers. However, the functions and underlying mechanisms of DLX6-AS1 have not been explored in OS yet. In this study, we assessed the expression of DLX6-AS1 in OS tissues and cell lines and explored the underlying molecular mechanisms. DLX6-AS1 was found to be significantly upregulated in OS tissues and OS cell lines. High expression of DLX6-AS1 was significantly correlated with advanced TNM stage, high tumor grade, and distant metastasis of patients with OS. Knockdown of DLX6-AS1 suppressed OS cell proliferation, invasion, and migration, and induced cell apoptosis. Knockdown of DLX6-AS1 also suppressed in vivo tumor growth. Bioinformatics and luciferase assay analysis showed that DLX6-AS1 functioned as a competing endogenous RNA (ceRNA) to negatively regulate miR-641 expression.Furthermore, miR-641 was found to target the 3′ untranslated region of homeobox protein Hox-A9 (HOXA9) and suppressed the expression of HOXA9.Mechanistic studies showed that DLX6-AS1 regulated OS cell proliferation, invasion, and migration via regulating HOXA9 by acting as a ceRNA for miR-641. Our results suggested that DLX6-AS1 functions as a ceRNA by targeting miR-641/HOXA9 signal pathway to suppress OS cell proliferation and metastasis. Our study may provide novel insights into understanding pathogenesis and development of OS. K E Y W O R D SceRNA, DLX6-AS1, HOXA9, miR-641, osteosarcoma

Background/Aims: Long non-coding RNAs (lncRNAs) are theorized to play key roles in the development of heart diseases. However, the role of lncRNAs in cardiomyocyte apoptosis is largely unknown. The present study examined the role of lncRNA SNHG1 in the human cardiomyocytes (HCMs) apoptosis and explored the underlying molecular mechanisms. Methods: SNHG1, miR-195 and mRNA expression was detected by qRT-PCR; protein level was determined by western blot; cell viability was detected by MTT assay; cell apoptosis was evaluated by flow cytometry and caspase-3 activity assay; the interaction between SNHG1 and miR195 was examined by using luciferase reporter assay. Results: Hydrogen peroxide (H₂O₂) treatment significantly suppressed cell viability and increased cell apoptotic rate and caspase-3 activity in HCMs. Overexpression of SNHG1 attenuated the effects of H₂O₂ on HCMs viability and apoptosis; while SNHG1 exerted the opposite effects. SNHG1 was found to sponge miR-195 and suppress the expression of miR-195 in HCMs. Overexpression of miR-195 suppressed cell viability and induced apoptosis in HCMs, and miR-195 was found to negatively regulate the expression of BCL-2 like protein 2 (BCL2L2) via targeting its 3’ untranslated region. Overexpression of BCL2L2 partially reversed the effects of miR-195 overexpression on cell viability and cell apoptosis of HCMs. MiR-195 overexpression or BCL2L2 knockdown attenuated the effects of SNHG1 overexpression on cell viability, cell apoptosis and protein levels of cleaved caspase-3, cleaved caspase-9 and Bax in H₂O₂-treated HCMs. Conclusion: Our results suggest a novel SNHG1/miR-195/BCL2L2 axis in the regulation of cardiomyocyte apoptosis. Modulation of SNHG1 may represent a novel strategy to treat cardiomyocyte apoptosis-related heart diseases.

In this study, the synergistic effect of vancomycin, a cell wall synthesis inhibitor, and ultrasound-targeted microbubble destruction (UTMD), on cell viability of Staphylococcus epidermidis, embedded in biofilm, was investigated. Biofilms are the leading causes of antibiotic-resistant bacterial infections of medical implants and prosthetics worldwide. The antibiotic-resistant nature of biofilm-embedded pathogens poses a critical challenge to the medical community. Previously, studies have demonstrated the efficacy of using ultrasound waves and UTMD in circumventing this problem. However, the mechanism(s) underlying this phenomenon was not clear. Here, the present study showed that both ultrasound and UTMD damaged the cell wall structure of S. epidermidis, and floccules and fragments from damaged cells were observed on transmission electron microscope micrograph. However, the cell membrane integrity was not seriously affected by treatments, and the treatment increased the metabolic activity levels of the dormant biofilm-embedded bacteria, detected by confocal laser scanning microscope and flow cytometry, which could make them susceptible to the effect of the antibiotic. Thus, the biological mechanism underlying the efficacy of the combined treatment involving UTMD and vancomycin in the case of S. epidermidis biofilm was dissected, which may be utilized for further investigations on other biofilm pathogens before clinical use.

Introduction High‐fluorescent cells (HFCs) that are detected with an automated hematology analyzer may be useful for the detection of tumor cells; however, the diagnostic ability of HFCs for differentiating malignant pleural effusion is limited. The aim of this study was to investigate the diagnostic value of the combined detection of HFCs with the tumor marker carcinoembryonic antigen (CEA) for the identification of malignant hydrothorax. Methods A total of 115 pleural effusions were collected. HFCs, including the relative counts (HF‐BF%) and absolute counts (HF‐BF#), were analyzed using the BF mode of a Sysmex XN9000 hematology analyzer. Simultaneously, the CEA level from the same patient was measured by an electrochemiluminescence method. Receiver operating characteristic (ROC) curve analysis was employed to evaluate the diagnostic accuracy of HFCs separately or combined with CEA analysis for malignant diseases. Results The levels of HF‐BF#, HF‐BF%, and CEA in the malignant effusion group were significantly higher than those in the benign control group. The diagnostic value of the HF‐BF# and HF‐BF% for malignant pleural effusion was low to moderate, and the area under the curve (AUC) was 0.663 and 0.715, respectively. The CEA detection showed a moderate diagnostic ability, and the AUC was 0.832. The AUC for the combined methods was 0.860 and 0.890, respectively. The cutoff levels of the HF‐BF#, HF‐BF%, and CEA levels were 29.5 × 106/L, 5.6/100 WBC, and 4.795 ng/mL, respectively. Conclusions The combined detection of high‐fluorescent cells with the BF mode and CEA testing may be a good indication for malignancy.

Ischemia/reperfusion (I/R) injury could cause the enhanced cell apoptosis of cardiomyocytes, which is one of key contributors for the development of ischemic heart disease. Recent studies emphasized the role of microRNAs (miRNAs) in regulating cardiomyocyte apoptosis. The study planned to elucidate the molecular actions of miR‐885 on mediating human cardiomyocytes (HCMs) apoptosis induced by hypoxia/reoxygenation (H/R) and to explore the potential molecular mechanisms. The present data revealed that H/R stimulation inhibited HCM viability and potentiated HCM apoptosis, and more importantly, the expression of miR‐885 in HCMs was markedly repressed after H/R stimulation. Further experimental examinations demonstrated that overexpression of miR‐885 attenuated H/R‐induced increased in HCM apoptotic rates, while miR‐885 knockdown impaired HCM viability and increased HCM apoptotic rates. Moreover, the mechanistic studies showed that miR‐885 inversely regulated the expression of phosphatase and tensin homolog (PTEN) and BCL2 like 11 (BCL2L11) in HCMs, and enforced expression of PTEN and BCL2L11 partially antagonized the protective actions of miR‐885 overexpression on H/R‐induced HCM injury. Moreover, H/R suppressed AKT/mTOR signaling, which was attenuated by miR‐885 overexpression in HCMs. In conclusion, the present study for the first time showed the downregulation of miR‐885 induced by H/R in HCMs, and provided the evidence that miR‐885 attenuated H/R‐induced cell apoptosis via inhibiting PTEN and BLC2L11 and modulation of AKT/mTOR signaling in HCMs.