Objective To investigate the effects of tobacco smoke exposure on histone deacetylase 2 (HDAC2),interleukin-8(IL-8)and tumor necrosis factor-α(TNF-α)expression in peripheral blood of patients with lung adenocarcinoma and analyze the relationships among them. Methods Seventy-three cases diagnosed as lung adenocarcinoma were collected in the First Affiliated Hospital and Affiliated Tumor Hospital of Guangxi Medical University from April 2014 to March 2015.All patients underwent lung function test preoperatively.Fourteen healthy volunteers without tobacco smoke exposure and chronic obstructive pulmonary disease (COPD)were recruited as healthy control.According to the lung function and tobacco smoke exposure,all cases were divided into four groups,ie. a healthy control group (group A,14 cases),a group without tobacco smoke exposure and COPD(group B,19 cases),a group with tobacco smoke exposure and without COPD(group C,33 cases),and a group with tobacco smoke exposure and COPD(group D,21 cases).The expressions of HDAC2 mRNA,IL-8 mRNA and TNF-α mRNA in peripheral blood mononuclear cells (PBMCs)were detected by real-time polymerase chain reaction (PCR).The contents of IL-8 and TNF-α in serum were detected by ELISA. Results Compared with group A,the HDAC2 mRNA expression in PBMCs had no difference in group B(P>0.05),and was down-regulated significantly in group C and D (P<0.05),which in group D was the most obvious.Compared with group A,the expressions of IL-8 mRNA and TNF-α mRNA in PBMCs and the contents of IL-8 and TNF-α in serum were significantly higher in all lung adenocarcinoma patients(all P<0.05),and the up-regulation was more obvious in group D.The relative expression of HDAC2 mRNA in PBMCs showed no significant difference with respect to age,gender or TNM stage (P>0.05).IL-8 and TNF-α in PBMCs and serum showed no significant difference with respect to age and gender (P>0.05),and were higher in the patients with TNM stage Ⅲ lung adenocarcinoma than those with stage Ⅰ and Ⅱ(P<0.05),with no obvious difference between stage Ⅰ and stage Ⅱ (P>0.05). Conclusion Tobacco smoke exposure causes lower expression of HDAC2 and over-expression of IL-8 and TNF-α in peripheral blood of patients with lung adenocarcinoma,can aggravate inflammatory response especially when complicated with COPD,which may be related to the prognosis of lung adenocarcinoma.
ObjectiveTo investigate the expression of histone deacetylase 2 (HDAC2) in animal model of benign tracheal stenosis, and explore the mechanism of HDAC2 in development of tracheal stenosis.MethodsEighteen rabbits were randomly divided into a blank control group, a model group, and an erythromycin group, with 6 rats in each group. The model group and the erythromycin group underwent tracheostomy, the inner wall of trachea was brushed back and forth with a nylon brush for more than 20 times to induce benign tracheal stenosis. From 7 days before surgery to 9 days after surgery, the model group received gavage with saline, the erythromycin group received gavage with low-dose erythromycin in dose of 15 mg·kg–1·d–1, and the control group did not receive any treatment. On the 10th day after operation, all the rabbits were sacrificed and the trachea was cut to measure the tracheal stenosis. RNA and protein were extracted from the granulation tissue in the stenosis and the relative mRNA expressions of HDAC2, interleukin (IL)-6 and IL-8 in the granulation tissue were detected by real-time fluorescence quantitative PCR. The relative expression of HDAC2 protein was detected by Western blot.ResultsCompared with the blank control group, the tracheal stenosis in the model group was more obvious [(84.60±1.14)% vs.(27.00±6.44)%], the mRNA and protein expressions of HDAC2 were decreased (0.29±0.07 vs. 1.00±0.00, 0.20±0.02 vs. 0.49±0.04), the mRNA expressions of IL-6 and IL-8 were up-regulated (4.22±0.67 vs. 1.00±0.00, 162.72±23.23 vs.1.00±0.00). Compared with the model group, tracheal stenosis in the erythromycin group was relieved [(64.00±12.25)% vs. (84.60±1.14)%], the mRNA and protein expressions of HDAC2 were increased (0.42±0.14 vs. 0.29±0.07, 0.43±0.01 vs. 0.20±0.02), the mRNA expressions of IL-6 and IL-8 were decreased (0.72±0.24 vs. 4.22±0.67, 130.22±7.93 vs. 162.72±23.23). All the differences were statistically significant (all P<0.05). The Pearson correlation coefficient between tracheal stenosis and HDAC2 mRNA relative expression was –0.96 (P<0.05).ConclusionsThe down-regulation of HDAC2 expression in model of benign tracheal stenosis is related to the occurrence and development of tracheal stenosis. The low dose of erythromycin may be used to treat benign tracheal stenosis by up-regulating expression of HDAC2 and thus inhibiting the inflammatory disorder during tracheal injury repair.
ObjectiveTo summarize mechanism of DNA methylation and histone methylation in liver fibrosis.MethodThe literatures on the DNA methylation and histone methylation during the liver fibrosis were reviewed and analyzed.ResultsThe DNA methylation and histone methylation were the important components of epigenetics. The up-regulation or down-regulation of genes during the liver fibrosis leaded to the activation or inactivation of the subsequent pathways. For example, the PTEN, SEPT9, Smad7, etc. were hypermethylated and the expressions were decreased in the liver fibrosis. The Spp1 was hypomethylated and the expression was increased in the liver fibrosis.ConclusionsMethylation affects expression of genes by altering epigenetics of genes. Systematic and in-depth study of role and mechanism of methylation in liver diseases provides a new direction and locations for some target treatments for liver disease.
Objective To investigate the effects of DNA methyltransferase inhibitor (DNMTi) and histone deacetylase inhibitor (HDCAi) on expression of E-cadherin gene and invasiveness of cholangiocarcinoma cell. Methods According to different treatment, the QBC939 cells were divided into four groups: blank control group, hydralazine group, valproic acid group and hydralazine and valproic acid combined group. After 48 h, the expression of E-cadherin was evaluated by reverse transcription-PCR (RT-PCR), mehtylation specific PCR (MSP) and Western blot, the invasiveness of QBC939 cells was evaluated by Transwell method. Results There was no expression of E-cadherin mRNA and protien in blank control group and valproic acid group. The expressions of E-cadherin mRNA and protien in hydralazine and valproic acid combined group were higher than those in hydralazine group ( P ＜ 0.01), while the invasiveness of QBC939 cells of hydralazine and valproic acid combined group was much lower than that of blank control group, hydralazine group and valproic acid group ( P ＜ 0.01). Conclusion DNMTi and HDACi can synergistically re-express E-cadherin gene and weaken the invasiveness of QBC939 cell, which plays an important part in treatment of cholangiocarcinoma.
Objective To investigate the effects of histone modification on the expression of chemokines in alveolar epithelial typeⅡ cells ( AECⅡ) in a rat model of chronic obstructive pulmonary disease ( COPD) . Methods 20 SD rats were randomly assigned to a normal control group and a COPD group. The rat model of COPD was established by cigarette smoking. Lung histological changes were observed by HE staining. AECⅡ cells were isolated and identified by alkaline phosphatase staining and electron microscopic. The mRNA expressions of monocyte chemoattractant protein ( MCP) -1, IL-8, and macrophage inflammatory protein ( MIP) -2αwere detected by real-time quantitative PCR. The expression of histone deacetylase ( HDAC) 2 was measured by western blot. Chromatin immunoprecipitation ( ChIP) was used todetect H3 and H4 acetylation, and H4K9 methylation in the promoter region of chemokine gene. Results Compared with the control group, the mRNA expressions of MCP-1, IL-8, and MIP-2αin the COPD group increased 4. 48,3. 14, and 2. 83 times, respectively. The expression of HDAC2 protein in the COPD group wassignificantly lower than in the control group ( 0. 25 ±0. 15 vs. 0. 66 ±0. 15, P lt; 0. 05) . The expression of HDAC2 had a negative correlation with the gene expressions of IL-8, MCP-1, and MIP-2α( r = - 0. 960,- 0. 914, - 0. 928, respectively, all P lt;0. 05) . The levels of H3 and H4 acetylation were higher, and H4K9 methylation level was lower in the promoter region of chemokine gene in the COPD group compared with the control group ( all P lt; 0. 05) . Conclusions MCP-1, IL-8, and MIP-2α participate and promote the lung inflammatory response in COPD. HDAC2-mediated histone modification may play an important role in COPD inflammation.
Retinoblastoma (RB) is a common intraocular tumor in children, often leading to blindness or disability, and its pathogenesis involves genetic and epigenetic regulation. Epigenetics regulates gene expression through mechanisms such as DNA methylation and histone modification without altering the DNA sequence, and the imbalance of its homeostasis is considered a crucial factor in the development and progression of RB. Therapeutic strategies targeting these abnormal modifications offer new potential treatment avenues for RB. Although current research has highlighted the importance of epigenetics in RB, the specific mechanisms of action, the relationship with genetic bases, and the development of targeted drugs remain largely unknown. Therefore, further in-depth research into the epigenetic mechanisms of RB is of great significance for elucidating its carcinogenic mechanisms, identifying effective therapeutic targets, and developing new drugs.
ObjectiveTo investigate the neuroprotective effects and mechanisms of selective histone deacetylases inhibitor MS-275 on rats after seizures. MethodsA total of 75 rats were randomly divided into 5 groups for treatment:control group,pilocarpine group, treatment group Ⅰ(administered with MS-275, 20mg/kg, once a day,intraperitoneally in 7 consecutive days), treatment group Ⅱ(administered with MS-275, 40mg/kg, once a day, intraperitoneally in 7 consecutive days), MS-275 pretreatment group. We used lithium and pilocarpin to induce seizures. Behaviors of rats in each group were observed. At 72 hours after seizures, Nissl staining and immunohistochemical were respectively used to evaluate the loss of neurons and histone acetylation levels of hippocampal CA1 and CA3 regions in each group. Escape latency in the control group, treatment group Ⅰ, treatment group Ⅱ and MS-275 pretreatment group were longer than pilocarpine group(P<0.05). ResultsCompared with the pilocarpine group, rats in MS-275 pretreatment group could delay pilocarpine-induced seizures and reduce mortality (P<0.05). Degree of neuronal loss and degeneration in both treatment group Ⅰ and treatment group Ⅱ were reduced compared with the pilocarpine group (P<0.05) and the level of histone acetylation in hippocampal CA1 and CA3 regions of the rats were increased compared with the pilocarpine group (P<0.05). ConclusionHDACs inhibitors MS-275 can improve the neuronal damage, histone deacetylation of rats' brain and rats cognitive decline, which can exert an neuroprotective effect on rats after seizures, whose mechanism may be related to its antiinflammatory effect.
Objective To review the relationship between histone modifications and gastrointestinal cancer. Methods Literatures on histone modifications and the relationship between histone modifications and gastrointestinal cancer were collected and reviewed. Results Histone modifications played an important role in the establishment of gene silencing during tumorgenesis. DNA methylation and histone modifications might interact with each other and form a complex network to establish and maintain gene silencing. Restoring gene function silenced by epigenetic changes in cancer had the potential of ‘normalizing’ cancer cells, which was named epigenetic therapy. Epigenetic therapy was very promising in prevention and treatment of gastrointestinal cancer, but many unsolved issues remain which need to be addressed in future studies. Conclusion Histone modifications are associated with the pathogenesis of gastrointestinal cancer. Restoring gene function silenced by epigenetic changes may have a great role in the prevention and treatment of gastrointestinal cancer.
The regulation of epigenetics on bone marrow mesenchymal stem cells (BMSCs) has been a research hot spot in medical area. This paper mainly summarizes the progress of the regulation of DNA methylation, histone acetylation, small interfering RNA (siRNA) induced gene silence and microRNA (miRNA) on BMSCs. Our analysis shows that the regulation of epigenetics on BMSCs plays a significant role in the repair of bone tissue, nervous tissue and cardiac muscle.