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Objective: MicroRNA (miRNA) can widely regulate gene expression. More importantly, various miRNA molecules have been found with regulatory functions for tumor cell proliferation or apoptosis. The study showed that miR-21 inhibited apoptosis of cultured cancer cells, whilst tumor necrosis factor α (TNF-α) plays important roles in the proliferation of tumor cells. This study manipulated miR-21 expression in cultured oral cancer cells and aimed to investigate its effects on TNF-α expression, and on proliferation or apoptosis of cancer cells., Materials and Methods: Specific agonist and antagonist were synthesized based on miR-21 sequence. In vitro cultured oral cancer cell line, SCC-15 was transfected with agonist or antagonist, in parallel with normal cultured cells as negative control group. Quantitative Real-time PCR (qRT-PCR) was used to measure mRNA expression of miR-21 and TNF-α in transfected cells. Western blot was used for measuring TNF-α expression, and 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) or Hoechst-33342 staining was used to measure proliferation and apoptosis of SCC-15 cells., Results: MiR-21 expression was potentiated or depressed with transfection of agonist or antagonist, respectively, illustrating the effectiveness of synthesized sequence in cultured SCC-15 cells. Moreover, TNF-α expression was positively correlated with miR-21, TNF-α up-regulation significantly potentiated the proliferation potency of SCC-15 cells, and TNF-α down-regulation remarkably weakened proliferation potency (p<0.05). The TNF-α expression did not affect apoptosis of SCC-15 cells (p>0.05 compared to the control group)., Conclusions: MiR-21 could participate in the proliferation of cultured SCC-15 cells via targeting TNF-α expression, but without any significant effects on cell apoptosis.

Purpose: To determine whether preserved human amniotic membrane can reduce corneal haze and keratocyte apoptosis induced by excimer laser photoablation in rabbit corneas., Methods: Excimer photoablation was performed bilaterally in 30 rabbits with a 6.0 mm ablation zone and 120 microm depth using the VISX Star laser with the phototherapeutic keratectomy (PTK) mode. One eye was randomly covered by preserved human amniotic membrane secured with 4 interrupted 10-0 nylon sutures, and the other eye served as the control. The amniotic membranes were removed at 1 week, and corneal haze was graded with slitlamp biomicroscopy by 3 masked corneal specialists biweekly for the ensuing 12 weeks until the rabbits were killed. Another 18 rabbits were divided into 4 subgroups and received PTK alone, PTK with membrane, PTK with sham sutures, or PTK with tarsorrhaphy. All eyes were studied histologically, and 3 eyes in each group were studied by in situ terminal deoxynucleotidyl transferase deoxy-UTP-nick end labeling assay at 1, 3, and 7 days and 12 weeks, respectively., Results: A consistent grading of differences in corneal haze scoring between the control corneas and the amniotic-membrane-covered corneas was noted among the 3 masked observers. Organized reticular post-PTK corneal haze peaked at 7 weeks in both groups, and the corneal haze score in the amniotic-membrane-covered group was significantly less than in the control group from 7 to 12 weeks (all P < .001). Compared to the control corneas, the amniotic-membrane-covered corneas had less inflammatory response at 1 and 3 days, less keratocyte apoptosis in the ablated anterior corneal stroma at 1, 3, and 7 days (P < .001), and less stromal fibroblast cellularity and epithelial hyperplasia at 12 weeks., Conclusions: Amniotic membrane matrix introduced at an early stage of the corneal wound healing process effectively reduced corneal haze induced by excimer laser photoablation in rabbits. Studies linking suppression of apoptosis in the acute wound-healing process with reduction of subsequent corneal scarring may have useful clinical applications.

OBJECTIVE: In recent years, coronary heart disease (CHD) has become a disease that cannot be ignored by residents of our country, because CHD will not only endanger people's quality of life, but also threaten their lives. Therefore, this research mainly explores the correlation between myocardial infarction (MI) with endoplasmic reticulum (ER) stress and apoptosis. MATERIALS AND METHODS: First, we constructed a model of myocardial ischemia and hypoxia (I/H) in vivo and in vitro, and examined the change of CACNA1H expression. At the same time, in order to research the role of CACNA1H, we chose CACNA1H-specific inhibitor ABT-639 to next research and detect changes in heart injury by detecting changes in creatine kinase (CK) content and lactate dehydrogenase (LDH) activity. Next, we used TUNEL staining and immunofluorescence staining to detect changes in apoptosis and ER stress, and analyzed changes in ER stress and apoptotic pathway expression by Western blotting and quantitative Real-Time Polymerase Chain Reaction (qRT-PCR). RESULTS: At 28 days after MI, the cardiac function of the mice was significantly reduced, the myocardial cell apoptosis rate was dramatically increased, and CACNA1H expression was dramatically increased in vivo and in vitro. In addition, we treated the model group with the ABT-639, and found that ABT-639 can partially protect myocardial function and relieve myocardial cell apoptosis. At the same time, ABT- 639 may reduce H9c2 injury after I/H by reducing the degree of ER stress, because we found that the use of ABT-639 can dramatically reduce ER stress-related factors expression, and can inhibit the expression of apoptosis-related factors Caspase-3 and Caspase-9. CONCLUSIONS: The CACNA1H inhibitor ABT- 639 can alleviate myocardial cell apoptosis caused by MI by reducing the ER stress response. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The aim of this study was to investigate the function and potential mechanism of micro ribonucleic acid (miR)-146a- 5p in oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: The expression of miR-146a-5p in OSCC tissues and cell lines was examined by quantitative Reverse Transcription-Polymerase Chain Reaction (qRTPCR) analysis. Then, the role of miR-146a-5p in proliferation was analyzed by Cell Counting Kit-8 (CCK-8) assay. Besides, the proliferation and apoptosis of OSCC cells were detected by the colony formation assay and flow cytometry, respectively. Finally, the regulatory effect of miR-146a-5p/nuclear factor-kappa B subunit 1 (NF-κB1) was determined by Western blotting assay and Luciferase reporter assay system. RESULTS: The expression of miR-146a-5p was markedly upregulated in OSCC cell lines. In addition, the silence of miR-146a-5p inhibited the proliferation and promoted the apoptosis of OSCC cells. According to the results of the Western blotting analysis and Luciferase reporter gene assay, NF-κB1 was identified as a direct target of miR-146a-5p. Moreover, the downregulation of NF-κB1 restored the inhibitory effect of silenced miR-146a-5p on the proliferation of SCC-9 cells. CONCLUSIONS: MiR-146a-5p can inhibit the proliferation and accelerate the apoptosis of OSCC cells by directly targeting NF-κB1, and it plays a carcinogenic role in OSCC. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To determine the protective effect of nicotinamide on chronic hypoxic myocardial cells and its underlying mechanism. MATERIALS AND METHODS: The H9C2 cell lines were taken as objects of study, and were divided into blank group, hypoxia group and nicotinamide treatment group. The cell viability, apoptosis level, autophagy level and mammalian target of rapamycin (mTOR) pathway activity in each group were detected via Cell Counting Kit-8 (CCK8) assay, Hoechst staining, immunofluorescence staining, Polymerase Chain Reaction (PCR) and Western blotting, respectively. RESULTS: Nicotinamide could protect the viability of normoxic and chronic hypoxic myocardial cells. Besides, it could also inhibit the expression of caspase3 messenger ribonucleic acid (mRNA) in chronic hypoxic myocardial cells, and reduce the expression of apoptosis-related proteins. Furthermore, it could induce the mRNA expression of autophagy-associated gene 5 (ATG5) and increase the expression of autophagy- related proteins. Further study on the mechanism of nicotinamide showed that nicotinamide could inhibit the activity of the mTOR pathway, thus regulating the autophagy. CONCLUSIONS: Nicotinamide induces the autophagy of chronic hypoxic myocardial cells by regulating the mTOR pathway, thereby protecting cells from apoptosis. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To investigate the effect of miR-875 on the proliferation and apoptosis of non-small cell lung cancer (NSCLC) cancer cell line A549 and the related mechanism. PATIENTS AND METHODS: 30 paired tumor tissue and the adjacent tissue were collected. Real Time-quantitative Polymerase Chain Reaction (RT-qPCR) has been performed to detect the expression of miR-875 in NSCLC tissues and adjacent normal tissues. Moreover, suppressor of cytokine signaling 2 (SOCS2) has been predicted as a target of miR-875, and Dual-Luciferase reporter assay has been performed to confirm the targeting relationship; furthermore, the expression of SOCS2 in tumor tissue and the adjacent tissue were compared. Next, human NSCLC cell line A549 cells were cultured and transfected with miR-875 inhibitor with or without SOCS2 siRNA, and the proliferation and apoptosis of the cells were evaluated by Cell Counting Kit (CCK-8) and flow cytometry methods. Finally, the relative protein expression of Wnt and β-catenin were analyzed by Western blot analysis. RESULTS: MiR-875 was significantly up-regulated in NSCLC tissues compared with the adjacent tissues. SOCS2 was confirmed as a target of miR-875, and the expression of SOCS2 was markedly decreased in NSCLC tissues. Moreover, the knockdown of miR-875 inhibited the proliferation and promoted the apoptosis of A549 cells, while transfection of SOCS2 siRNA can block miR-875 inhibitor-induced anti-proliferative effects. Finally, the transfection of miR-875 inhibitor decreased the expression of Wnt and β-catenin, and SOCS2 siRNA can reverse the effect. CONCLUSIONS: MiR-875 may regulate the proliferation and apoptosis of NSCLC cells via targeting SOCS2, suggesting that miR-875 has the potential to become a therapeutic target for the treatment in NSCLC. [ABSTRACT FROM AUTHOR]