Aim To investigate the effect of Ginsen-oside Rh2 on apoptosis in human colorectal cancer cell SW480,and to explore the possible mechanism of it. Methods The proliferation activity of SW480 treated with Ginsenoside Rh2 was measured CCK-8 assay.Ap-optosis rates were evaluated by FCM.Hoechst 33258 staining was used to observe cell nucleus morphologi-cal;change SW480 cells were treated with Ginsenoside Rh2,and the protein expressions of Bcl-2,Bax,p53, cleaved caspase-3 ,PI3 K,AKT,P-AKT,GSK-3β,P-GSK-3βwere detected by Western blot;SW480 cells were treated with LY294002,Rh2,LY294002+Rh2, the expressions of PI3 K,AKT,P-AKT,GSK-3β,P-GSK-3βwere detected by Western blot.Results The proliferation of SW480 cells was significantly inhibited by Ginsenoside Rh2 in dose-dependent and time-de-pendent manner.FCM showed the inducing apoptosis effect of Ginsenoside Rh2 was significantly different from that of control group.Hoechst 33258 staining in-dicated clearly cell apoptosis in Ginsenoside Rh2 treat-ment groups.Western blot showed Ginsenoside Rh2 decreased expression of Bcl-2,increased expression of Bax,p53 and cleaved caspase-3,PI3K/AKT/GSK-3βpathway proteins PI3 K,P-AKT,P-GSK-3βdecreased obviously,AKT and GSK-3βwere not changed signifi-cantly in SW480.SW480 cells were separately treated with LY294002,Rh2,LY294002 +Rh2,there were no significant difference in AKT and GSK-3βprotein a-mong all groups,and the expression of PI3 K,P-AKT, P-GSK-3βdecreased more obviously in LY294002 +Rh2 group compared with LY294002 and Rh2 alone. Conclusion Rh2 induces colorectal cancer cell apop-tosis through PI3 K/AKT/GSK-3βpathway,which ac-tivates p53 and cleaved caspase-3,and destroys the balance of Bcl-2/Bax.

Objective To understand the academic atmosphere current situation of graduate students and put forward relevant countermeasures to protect the academic integrity of graduate students.Methods The graduate student'scientific ethics and academic atmosphere construction situation of graduate students in 10 colleges and universities in Chongqing were investigated by questionnaire survey and analyzed.Results Through 1555 questionnaires,it was found that the average investment of time on scientific research in gruduate students was insufficient,the motivation of learning was complicated,and the situation of preventing academic misconduct was serious.Conclusion This study suggests that colleges and universities should establish an academic integrity security system for graduate students,including establishment of academic integrity system and specializing academic integrity supervision institutions,and strengthing academic integrity education.

Aim To investigate the effect of ribonucleic acidⅡon apoptosis in human leukemia cell lines K562 and KG1 a.Methods Cell counting kit-8(CCK-8)as-say was performed to detect proliferation activity of K562 and KG1 a cells treated with ribonucleic acidⅡ. Apoptosis index was assessed by flow cytometry(FCM) and fluorescent Hoechst 33258 staining was used for observing morphologic changes of apoptosis.Expres-sion levels of p53,Bax,Bcl-2 and cleaved caspase-3 were analyzed by Western blot.Results The prolifera-tion of K562 and KG1 a cells was significantly inhibited by ribonucleic acid Ⅱ treatment for 12 h,24 h,48 h at concentrations of 100~300 mg·L-1 ,which indica-ted the inhibitory effect of ribonucleic acid Ⅱ was in dose-dependent and time-dependent manners.FCM re-sults displayed a dose-dependent increase in cell apop-totic rate.Hoechst 33258 staining showed the typical apoptotic morphology in some leukemic cells treated with ribonucleic acid Ⅱ,including increased nuclear chromatin concentration and edge accumulation.West-ern blot analysis showed the increased expression of p53,Bax,cleaved caspase-3 and decreased expression of Bcl-2 in K562 and KG1 a cells treated with ribonu-cleic acid Ⅱ.Conclusions Ribonucleic acid Ⅱ can induce apoptosis of leukemia K562 and KG1 a cells by up-regulating p53,which mediates Bcl-2/Bax balance and activates caspase-3 .

Objective: To investigate the inhibitory effect of Rh2 on HepG2 cells and explore the underlying mechanism.Methods: We used lentivirus carrying β-catenin to infect HepG2 cell, and detected expression of β-catenin using fluorescence microscopy.The effect of Rh2 on proliferation of HepG2-β-catenin and HepG2 cells was measured by CKK-8 assay,and flow cytometry was used to detect cell cycle and apoptosis.The activity of Gsk-3βwas checked by ELISA kit.The expression of Gsk-3β,β-catenin,Bax,Bcl2,CyclinD1,MMP3 genes were measured by qRT-PCR.In order to checked the relationship between β-catenin and TCF4,CHIP assay kit was used,the expression of Bax,Bcl2,CyclinD1,MMP3 genes were measured by PCR.The expressions of Gsk-3β,β-catenin,Bax,Bcl2,CyclinD1,MMP3 proteins were examined by Western blot.Results:HepG2 cells were successfully infected by pLOV-EF1a-MCS-3FLAG-β-catenin lentivirus,named HepG2-β-catenin.CCK-8 showed that ginsenoside Rh2 could effectively inhibit the proliferation of HepG2 and HepG2-β-catenin cells in vitro,which exhibits a dose-dependent manner at range of 10-160 μmol/L Rh2.The IC50 of Rh2 exposure on HepG2 cell for 48,72 h were 100 μmol/L and 58.12 μmol/L,but the IC50 of Rh2 exposure on HepG2-β-catenin for 48,72 h were 129.2 μmol/L,83.33 μmol/L,respectively.The IC50 of Rh2 exposure on HepG2-β-catenin cell was higher than HepG2 cell, compared with HepG2 group the differences was statistically significant ( P<0.01 ).Flow cytometry indicated that Rh2 could arrest HepG2 and HepG2-β-catenin cells in G0/G1 phase;the cell population in G0/G1 phase of HepG2+Rh2 group was(64.57±0.65)%,HepG2-β-catenin+Rh2 group was(58.61±2.01)%.Flow cytometry indicated that Rh2 could induced early apoptosis in HepG2 and HepG2-β-catenin cells.The apoptosis rate of HepG2 +Rh2 group was (17.27 ±2.77)%,HepG2-β-catenin +Rh2 group(9.02 ±1.76)%.The ELISA results indicated that HepG2 cells was induced by Rh2 for 12,24,48,72 h,the activity of Gsk-3βgradually increased,peak in 48 h,then decreased.Compared with control group,Rh2 induced HepG2 and HepG2-β-catenin cells for 48 hours, Gsk-3βactivity were increased, and their activity reduced after adding Bio, there were no significant differences between HepG2+Rh2 and HepG2-β-catenin+Rh2 groups.The PCR,CHIP and WB results showed that the expression of Gsk-3β,Bax gene and proteins increased,while theβ-catenin,CyclinD1,Bcl2,MMP3 gene and proteins down-regulation in HepG2 and HepG2-β-catenin cell induced by Rh2.Compared with HepG2-β-catenin +Rh2 group, the expression of other gene and proteins changed significantly,however,Gsk-3βwas no significant difference.Conclusion:Over-expression of β-catenin may weaken the phar-macological effects of ginsenoside Rh2 on HepG2 cells.The activity of Gsk-3βwas increased by ginsenoside Rh2 to degradeβ-catenin, affecting the expression of downstream genes,promoting apoptosis of liver cancer cells and inhibiting metastasis.

Objective:To study the mechanism of ginsenoside Rh2 inhibiting HepG2 cells migration.Methods:HepG2 cells in logarithmic growth phase were cultured in 96-well plates,which were induced by different concentration Rh2,respectively for 24,48,72 hours.The cell inhibition was detected by Cell Counting Kit.Transwell chambers was used to checked HepG2 cell migration ability;luciferase was tested by Luciferase Reporter Assay system reagent;The expressions of P-ERK,ERK,P-P38,P-38,P-JUK,JUK,MMP3 proteins were detect by Western blot;the expression of AP1,MMP3 gene were detected by Quantitative PCR;The expression of AP1, MMP3 fluorescence protein were observed by fluorescence microscopy.Results:Administrated with different concentration of Rh2 after 24 ,48 ,72 h,the proliferation of HepG2 cells were inhibited ( P<0.05) ,and in dose-and time-dependent manner.Transwell assay showed Rh2 could significantly inhibited migration of HepG2 cells.The expressions of P-ERK , MMP3 proteins were significantly decreased,the expressions of P-JUK, P-P38 proteins were significantly increased, expression levels of ERK, P-38, JUK were no significant difference.Expression of AP1,MMP3 gene were significantly decreased,the expressions of AP1,MMP3 fluorescence proteins were significantly decreased.Conclusion:Ginsenoside Rh2 can activate MAPK pathway to inhibit the migration of HepG2 cells.

OBJECTIVETo investigate the inhibitory effect of trichostatin A (TSA) on the proliferation of HepG2 cells and explore the underlying mechanism.

METHODSHepG2 cells exposed to different concentrations of TSA for 24, 48, or 72 h were examined for cell growth inhibition using a cell counting kit, changes in cell cycle distribution with flow cytometry, cell apoptosis with annexin V-FTIC/PI double staining, and cell morphology changes under inverted microscope. The expressions of beta-catenin, HDAC1, HDAC3, H3K9, cyclinD1 and Bax proteins in the exposed cells were detected by Western blotting, and the expressions of HDAC1 and HDAC3 mRNAs by quantitative fluorescent PCR.

RESULTSExposure to TSA caused significant dose- and time-dependent inhibition of HepG2 cell proliferation (P<0.05) and resulted in increased cell percentage in G0/G1 and G2/M phases and decreased cell percentage in S phase. The apoptotic index in the control group was (6.22 ± 0.25)%, which increased to (7.17 ± 0.20)% and (18.14 ± 0.42)% after exposure to 250 and 500 nmol/L TSA, respectively. Exposure to 250 and 500 nmol/L TSA also caused cell morphology changes with numerous floating cells. The expressions of beta-catenin, H3K9 and Bax proteins were significantly increased and CyclinD1, HDAC1, and HDAC3 protein expressions decreased in TSA-treated cells, but the expressions of HDAC1 and HDAC3 mRNAs showed no significant changes.

CONCLUSIONSTSA can inhibit the proliferation of HepG2 cells and induce cell cycle arrest and apoptosis by inhibiting HDAC activity, promoting histone acetylation, and activating Wnt/beta-catenin signaling pathway.

Acetylation ; Apoptosis ; Cell Cycle Checkpoints ; Cell Proliferation ; drug effects ; Cyclin D1 ; metabolism ; Hep G2 Cells ; drug effects ; Histone Deacetylase 1 ; metabolism ; Histone Deacetylases ; metabolism ; Histones ; metabolism ; Humans ; Hydroxamic Acids ; pharmacology ; Wnt Signaling Pathway ; bcl-2-Associated X Protein ; metabolism ; beta Catenin ; metabolism

Objective To explore the postgraduate tutor assessment system in order to provide suggestions to improve the quality of postgraduate education. Methods Assessment indexes of post-graduate tutor were screened and assigned by methods of questionnaire investigation, interview, kruskal wallis H-test, taking a total of 109 students and professors in medical colleges in the south-western part as research objects. Results Different populations had different cognitions on the important degree of each index, P<0.05. Primary indexes of assessment system were determined based on the importance of indicators and the influence of different cognitive levels, including tutor personal accom-plishment, teaching ability, scientific research quality and guiding ability (P<0.05). Conclusions Assessment system and method fined by this study covers majority aspects of tutors and can provide feasible suggestions for tutor evaluation.

This paper discussed on the innovative efforts of establishing production-teaching-research platform and multi-channel international cooperation model by Chongqing Medical University. Measures taken included offering theoretical courses across the first-level disciplines of medicine and engineering and encouraging research tasks that involve the cooperation among hospitals , businesses and universities, creating education environment for postgraduates combing medicine and engineering and launching the cultivation of biomedical engineering postgraduates. The aim of these measures was to incorporate the achievements of scientific research innovation into postgraduate education and to improve its quality.

Objective To investigate the inhibitory effect of trichostatin A (TSA) on the proliferation of HepG2 cells and explore the underlying mechanism. Methods HepG2 cells exposed to different concentrations of TSA for 24, 48, or 72 h were examined for cell growth inhibition using a cell counting kit, changes in cell cycle distribution with flow cytometry, cell apoptosis with annexin V-FTIC/PI double staining, and cell morphology changes under inverted microscope. The expressions of beta-catenin, HDAC1, HDAC3, H3K9, cyclinD1 and Bax proteins in the exposed cells were detected by Western blotting, and the expressions of HDAC1 and HDAC3 mRNAs by quantitative fluorescent PCR. Results Exposure to TSA caused significant dose-and time-dependent inhibition of HepG2 cell proliferation (P<0.05) and resulted in increased cell percentage in G0/G1 and G2/M phases and decreased cell percentage in S phase. The apoptotic index in the control group was (6.22 ± 0.25)%, which increased to (7.17 ± 0.20)%and (18.14 ± 0.42)%after exposure to 250 and 500 nmol/L TSA, respectively. Exposure to 250 and 500 nmol/L TSA also caused cell morphology changes with numerous floating cells. The expressions of beta-catenin, H3K9 and Bax proteins were significantly increased and CyclinD1, HDAC1, and HDAC3 protein expressions decreased in TSA-treated cells, but the expressions of HDAC1 and HDAC3 mRNAs showed no significant changes. Conclusion TSA can inhibit the proliferation of HepG2 cells and induce cell cycle arrest and apoptosis by inhibiting HDAC activity, promoting histone acetylation, and activating Wnt/beta-catenin signaling pathway.

Objective To investigate the inhibitory effect of trichostatin A (TSA) on the proliferation of HepG2 cells and explore the underlying mechanism. Methods HepG2 cells exposed to different concentrations of TSA for 24, 48, or 72 h were examined for cell growth inhibition using a cell counting kit, changes in cell cycle distribution with flow cytometry, cell apoptosis with annexin V-FTIC/PI double staining, and cell morphology changes under inverted microscope. The expressions of beta-catenin, HDAC1, HDAC3, H3K9, cyclinD1 and Bax proteins in the exposed cells were detected by Western blotting, and the expressions of HDAC1 and HDAC3 mRNAs by quantitative fluorescent PCR. Results Exposure to TSA caused significant dose-and time-dependent inhibition of HepG2 cell proliferation (P<0.05) and resulted in increased cell percentage in G0/G1 and G2/M phases and decreased cell percentage in S phase. The apoptotic index in the control group was (6.22 ± 0.25)%, which increased to (7.17 ± 0.20)%and (18.14 ± 0.42)%after exposure to 250 and 500 nmol/L TSA, respectively. Exposure to 250 and 500 nmol/L TSA also caused cell morphology changes with numerous floating cells. The expressions of beta-catenin, H3K9 and Bax proteins were significantly increased and CyclinD1, HDAC1, and HDAC3 protein expressions decreased in TSA-treated cells, but the expressions of HDAC1 and HDAC3 mRNAs showed no significant changes. Conclusion TSA can inhibit the proliferation of HepG2 cells and induce cell cycle arrest and apoptosis by inhibiting HDAC activity, promoting histone acetylation, and activating Wnt/beta-catenin signaling pathway.