1.Optimization of the establishment protocol of a mouse model of MBA/TPA-induced skin cancer
Jiahui SUN ; Hui SHAN ; Xiaoyu PAN ; Yuchao GU
Acta Laboratorium Animalis Scientia Sinica 2017;25(1):31-35
Objective To induce skin cancer in BALB/c mice using DMBA as initiator and TPA as tumor promot-er. Through optimizing the doses and frequencies of DMBA administration to establish a stable skin cancer model with less time and causing less skin damage. Methods Shaving the back of mice to expose a piece of skin around 2 cm × 2 cm. The mice were divided into a blank control group and four treatment groups randomly. These four groups were given 1, 2, 4, 7 times 100μg/100μL DMBA/acetone, respectively, in the first week, and twice 4μg/100μL TPA/acetone per week in the next 11 weeks. The body weight changes, time of tumor formation and number of tumors formed were recorded during the experiment. The mice were sacrificed at 12th week and samples of tumor tissue and adjacent normal skin tissue were taken for pathological examination using HE staining. Results Tumors were observed at the 7th week in the group with once DMBA administration in the first week and at the 4th week in the group with twice DMBA administration in the first week. Skin cancers were formed also in the group with 4?time DMBA administration in the first week, however, with signif?icantly more severe skin damages. The mice receiving DMBA everyday in the first week died at the 3th week. Conclusions The best induction protocol for skin cancer in BALB/c mice should be twice DMBA in the first week followed by twice TPA
2.Role of trichostatin A in proliferation of human lung adenocarcinoma cell line NCI-H1299 and its mechanism
Hongjun GU ; Ning WU ; Haiyang HU ; Xiaolian SONG ; Yuchao DONG ; Qiang LI
China Oncology 2009;19(10):779-783
Background and purpose: Trichostatin A (TSA), an antifungal antibiotic with cytostatic and differentiating properties in mammalian cell culture, is a potent and specific inhibitor of histone deacetylase (HDAC). This study was aimed to investigate the influence of trichostatin A on the growth of human lung adenocacinoma cells in vitro, and to explore the mechanisms involved. Methods: MTT assay was employed to evaluate the inhibitory effect of TSA (0.1, 0.2,0.4 μmol/L) on the growth of human NCI-H1299 cancer cells. The cell cycle distribution and apoptotic ratio were determined by flow cytometry. The acetyl level of histone H4 after TSA treatment was detected by Western blot;the mRNA level of Bax,Bcl-2,p21 and cyelinBl was measured by Real-time PCR. Results: TSA inhibited the growth of NCI-H1299 cells in a dose-and time-dependent manner. Flow cytometry showed that the cells were blocked at G_2/M phase and cell apoptosis was increased compared to the control. TSA significantly increased the acetyl level of histone H4, induced p21 and Bax expression, and inhibited the expression of cyclin BI and Bcl-2. Conclusion: TSA inhibits the growth of lung cancer cells in vitro through inducing cell apoptosis and cell cycle arrest, which might be related to its regulatory effects on the acetyl blot of histone and the expression of p21, Bax, Bcl-2 and cyclinBl.
3.The deubiquitinase OTULIN promotes aerobic glycolysis and proliferation of gastric cancer cells
Haihui WEN ; Yuchao GU ; Qin LIU ; Bin WANG
Tumor 2023;43(12):905-919
Objective:To examine the expression of OUT domain deubiquitinase with linear linkage specificity(OTULIN)in gastric cancer tissues and explore the impact of OTULIN silencing on the proliferation of gastric cancer MKN45 and AGS cells as well as its underlying mechanisms. Methods:Immunohistochemical staining was performed to detect the expression level of OTULIN in 73 gastric cancer tissues and 24 normal gastric mucosa.The association between OTULIN expression and the prognosis as well as the clinicopathological features of gastric cancer patients was analyzed.The above results were validated using public data from The Cancer Genome Atlas(TCGA)database and Gene Expression Omnibus(GEO)database.CRISPR/Cas9 gene editing technology was used to construct OTULIN-knockout gastric cancer cells MKN45 and AGS.The efficiency of gene knockout was validated by Western blotting.The effects of OTULIN knockout on the proliferation of gastric cancer cells MKN45 and AGS were assessed by CCK-8 assay and soft agar colony formation assay.Immunoprecipitation-mass spectrometry technique was exploited to identify potential protein substrates interacting with OTULIN and linear ubiquitin molecule INT-Ub.7KR.The changes in the activity of rate-limiting enzymes for glycolysis were measured using pyruvate kinase(PK)activity assay kit and lactate production was analyzed by lactate colorimetric/fluorometric assay kit in OTULIN-depleted cells.The effect of OTULIN on substrate linear ubiquitination was evaluated using co-immunoprecipitation and Western blotting. Results:The expression level of OTULIN in gastric cancer tissues was higher than that in normal gastric mucosa(P=0.004 1)as revealed by immunohistochemical analysis.Patients with higher OTULIN expression in the cancer tissues had a lower suvival time(P=0.007 7).Analysis of datasets from TCGA and GEO databases also confirmed that OTULIN was highly expressed in gastric tissues(P<0.05)and high OTULIN expression was associated with poor prognosis(P=0.011).Statistical analysis also showed that higher expression of OTULIN was correlated with later TNM stages(P=0.027 3)and was an independent indicator for shorter survival time of gastric cancer patients(P=0.04).Knockout of OTULIN significantly inhibited the proliferation(P<0.000 1),decreased the activity of PK(P<0.01)and reduced lactate production(P<0.01)of gastric cancer cells.OTULIN interacted with several key enzymes in the glycolysis pathway and downregulated the linear ubiquitination levels of these enzymes,including pyruvate kinase M1(PKM1),PKM2,lactate dehydrogenase A(LDHA)and LDHB. Conclusion:OTULIN is a novel biomarker for predicting the prognosis of gastric cancer patients.It activates the glycolytic pathway and promote the progression of gastric cancer possibly by downregulating the linear ubiquitination modification of rate-limiting enzymes in glycolysis.
4.Analysis on influence of transsphenoidal approach pituitary adenoma resection in patients with complicating cardiomyopathy on serum growth hormone level and cardiac structural function
Junyi GU ; Xiangdong LI ; Zhong WANG ; Zhengquan YU ; Youxin ZHOU ; Gang CHEN ; Yuchao CHEN ; Yuzhao LIU
Chongqing Medicine 2017;46(36):5065-5067
Objective To study the surgical treatment and clinical effect of growth hormone type pituitary tumor complica-ting cardiomyopathy .Methods Sixty-five cases of growth hormone type pituitary adenoma complicating cardiomyopathy in the hos-pital from June 2012 to June 2016 were selected and performed transsphenoidal approach pituitary adenoma resection .Then serum growth hormone level ,ECG results ,ultrasound cardiogram results and clinical symptoms were observed at 2 weeks after operation . Results The signs were significantly improved after surgery ,acromegaly and nasolabial hypertrophy were significantly improved , dizziness ,fatigue ,hypertension and hyperglycemia were significantly improved ;the average postoperative growth hormone level was (4 .37 ± 2 .03)μg/L ,which was significantly lower than (40 .27 ± 4 .18)μg/L before operation ,and the difference was statistically significant (P< 0 .01 );postoperative IVST ,LVIDd and LVPWT were significantly lower than those before operation ,and the difference was statistically significant (P<0 .01);postoperative average E/A and LVEF were significantly lower than those before operation ,and the difference was statistically significant (P<0 .01) .Conclusion Transsphenoidal pituitary tumor resection can re-duce the level of grow th hormone and improves the cardiac function .