1.Reversal effect of isotetrandrine, an isoquinoline alkaloid extracted from Caulis Mahoniae, on P-glycoprotein-mediated doxorubicin-resistance in human breast cancer (MCF-7/DOX) cells
Acta Pharmaceutica Sinica 2008;43(5):461-466
This study investigated the reversal effect of isotetrandrine, an isoquinoline alkaloid extracted from Caulis mahoniae, on P-glyeoprotein-mediated multidrug resistance in human breast cancer doxorubicin-resistant (MCF-7/DOX) cells. RT-PCR assay and immunity histochemistry assay were used to determine the expression level of mdrl gene and P-gp in MCF-7/DOX cells to elucidate resistant character of MCF-7/DOX cells. The activity of isotetrandine to enhance doxorubicin cytotoxicity was tested using MTT (3-(4,5-dimethyhhiazol)-2,5-diphenyltetrazolium bromide) assay and was evaluated by the reversal fold (RF) values. Intracellular accumulation of doxorubicin was assessed by the determination of doxorubicin-assoeiated fluorescence intensity. Effect of isotetrandrine on the expression level of P-gp in MCF-7/DOX cells was then determined by immunity histochemistry assay. The ability of isotetrandrine to inhibit P-gp function was evaluated by detecting the accumulation and efflux of rhodamine123 ( Rh123 )with flow cytometry (FCM). Verapamil was employed as a comparative agent in whole experiment. The results indicated that MCF-7/DOX cells had phenotype of MDR and that the positive expression of P-gp MCF-7/DOX cells and reversal fold (RF) was significantly higher than that of verapamil (P < 0.05 ), butit hardly affected cytotoxicity of DOX in MCF-7 cells and the expression level of P-gp in MCF-7/DOXcells. The ability of isotetrandrine to inhibit P-gp function was reversible, because incubation of MCF-7/DOX cells with isotetrandrine caused a marked increase in uptake and a notable decrease in efflux of Rh123 and a marked increase of intracellular DOX concentrations. In conclusion, isotetrandrine exhibited potent effect on the reversal of P-gp-mediated MDR in vitro, suggesting that it might become a candidate of effective MDR reversing agent in cancer chemotherapy.
2.Small interfering RNA targeting STAT3 enhances antitumor activity of doxorubicin.
Tianxiao WANG ; Yingying WANG ; Zhongqing ZHANG
Acta Pharmaceutica Sinica 2013;48(1):52-8
This study is to investigate the effect of small interfering RNA targeting STAT3 (STAT3-siRNA) enhancing antitumor activity of doxorubicin. RT-PCR and Western blotting were used to test the expression of STAT3 mRNA and protein in the HepG2, HeLa and K562/DOX cells and the effect of STAT3-siRNA on the expression of STAT3 mRNA and protein. MTT and Trypan blue assay were performed to determine the inhibitory effect of STAT3-siRNA on HepG2, HeLa and K562/DOX cells and the effect of STAT3-siRNA enhancing antitumor activity of doxorubicin. The effects of STAT3-siRNA on intracellular accumulation of doxorubicin and cell apoptosis were performed by Arrary Scan V(TI)HCS600 High-Contents. The results showed that STAT3 gene, STAT3 and pSTAT3 protein were highly expressed in HepG2, HeLa and K562/DOX cells and STAT3-siRNA decreased the expression of STAT3 mRNA and protein. STAT3-siRNA inhibited the growth of HepG2, HeLa and K562/DOX cells. STAT3-siRNA in combination with doxorubicin decreased by 3.13, 5.22 and 1.74 fold of IC50 of HepG2, HeLa and K562/DOX cells compared with doxorubicin only. Intracellular accumulation of doxorubicin increased by 16.8%, 12.87% and 25.67% respectively in HepG2, HeLa and K562/DOX cells in the presence of STAT3-siRNA. An enhancement of doxorubicin-induced cell apoptosis was observed in HepG2, HeLa and K562/DOX cells treated with STAT3-siRNA. The results suggested that STAT3-siRNA could enhance the antitumor activity of doxorubicin on HepG2, HeLa and K562/DOX cells.
3.Challenges and strategies in the diagnosis and treatment of pancreatic cancer
Taiping ZHANG ; Tianxiao WANG ; Yupei ZHAO
Chinese Journal of Digestive Surgery 2012;11(1):41-44
Pancreatic cancer is an aggressive malignant gastrointestinal tumor,surgical resection offers the only chance of cure. Due to its anatomic and biological characters,early stage pancreatic cancer is usually clinically silent,80%-85% of patients present with advanced unresectable disease. Furthermore,pancreatic cancer responds poorly to most radiochemotherapeutic agents.In this article,we discuss some clinical aspects including early diagnosis,preoperative systemic assessment,surgery and perioperartive adjuvant therapy,and we hope to find the challenges as well as strategies for pancreatic cancer in order to further improve the current level of diagnosis and treatment in China.
4.Endogenous cystathionine-gamma-lyase/hydrogen sulfide pathway regulates apoptosis of HepG2 cells.
Tianxiao WANG ; Xiaoyan SHI ; Yinghua LIU
Acta Pharmaceutica Sinica 2013;48(8):1233-40
This study is to investigate the role of endogenous CSE/H2S in regulating apoptosis of HepG2 cells. MTT and Trypan blue assay were performed to determine the effect of CSE inhibitor PAG and CSE siRNA on proliferation of HepG2. Production of H2S from HepG2 cells was assessed spectrophotometrically using N, N-dimethyl-p-phenylenediamine-dihydrochloride. Cells apoptosis was detected by means of double staining of Hoechst 33342 and PI with Array Scan V(TI)HCS600 High-Contents. Dihydroethidine (DHE) and 2', 7'-dichlorodihydrofluorescein diacetate (DCFH-DA) assay was used to determine intracellular superoxide anion and ROS level. Reduced glutathione (GSH) was determined by OxiSelect Total Glutathione Assay Kit. Recombinant plasmid pcDNA 3.1/myc-His(-)-CSE was constructed and transfected into 293T cells to rescue the ROS and GSH level to further investigate the effect of CSE/H2S on ROS and GSH. Western blotting was performed to test the effect of CSE siRNA on expression of activated caspase 3 and p-AKT and Nrf2 protein. The results showed that PAG and CSE siRNA could significantly decrease the production of H2S in HepG2 cells and inhibit the proliferation of HepG2 cells at a dose-dependent and time-dependent manner, respectively. PAG and CSE siRNA could promote the cell apoptosis of HepG2 cells. Moreover, PAG and CSE siRNA induced increased ROS generation and depletion of the critical antioxidant GSH and recombinant plasmid pcDNA 3.1/myc-His(-)-CSE rescued the level of ROS and GSH. Meanwhile, CSE siRNA increased the expression of activated caspase 3, but CSE siRNA did not affect the expression of p-AKT and Nrf2. These results suggested that the CSE/H2S pathway was involved in suppression of HepG2 cell growth and promoted apoptosis of HepG2 cells in an oxidative stress-dependent manner.
5.FFJ-5 inhibits growth of MCF7 cells and reverses drug resistance of MCF7/DOX cells via down-regulation of PKM2
Tianxiao WANG ; Xiaoli WEI ; Dengyun LI
Chinese Pharmacological Bulletin 2015;(5):721-725,726
Aim To investigate the roles of FFJ-5 in human breast cancer MCF7 cells and drug-resistant MCF7/DOX cells and to explore its mechanisms. Methods MTT assay was used to detect the effect of FFJ-5 on MCF7 and MCF7/DOX cell proliferation and sensitivity of doxorubicin in MCF7/DOX cells.West-ern blot was used to investigate the effect of FFJ-5 on expression of EGFR,p-EGFR,Akt,p-Akt,PKM2, cleaved caspase-3,cleaved PARP and P-gp.DNA lad-der analysis was performed to determine the effect of FFJ-5 on genomic DNA.RT-PCR was performed to de-tect the influence of FFJ-5 on multidrug resistance gene MDR1 mRNA levels.Results The results showed that FFJ-5 inhibited the growth of MCF7 ,inhibited the expression and activity of EGFR and Akt,and conse-quently reduced the expression of PKM2 in MCF7 cells;FFJ-5 activated caspase-3 and induced genomic DNA fragmentation;FFJ-5 also inhibited the growth of MCF7/DOX cells and enhanced the anti-tumor activity of doxorubicin in MCF7/DOX cells.Conclusion The results suggest that FFJ-5 could inhibit MCF7 cell growth and induce MCF7 cell apoptosis through inhibi-tion of EGFR-Akt-PKM2 pathway and activation of ap-optosis-related factors caspase-3 , meanwhile FFJ-5 could also reverse the resistance of MCF7/DOX.
6.Endovascular embolization with detachable balloon for traumatic carotid-cavernous fistulae:clinical experience in 188 cases
Ziliang WANG ; Bin XU ; Tianxiao LI
Journal of Interventional Radiology 2015;(9):754-758
Objective To evaluate the clinical efficacy of endovascular embolization with detachable balloon, based on the characteristics of traumatic carotid-cavernous fistulae (TCCF), in treating TCCF. Methods The clinical data of 188 patients with TCCF, who had received endovascular embolization with detachable balloon via femoral artery access, were retrospectively analyzed. The risk factors for recurrence were statistically analyzed. Results Of the total 188 patients, complete cure after the first balloon embolization was obtained in 160, certain improvement of clinical symptoms was achieved in 22, and balloon embolization failed in 6, for whom other surgical options had to be carried out. Complications occurred in three patients. Recurrence was seen in 23 patients within the period from one day to 5 years after the treatment, and the recurrent lesion was successfully cured in all patients. Univariate analysis and chi square test or correction chi square test indicated that factors affecting postoperative recurrence were the use of multiple balloons for embolization and the presence of residual fistula after operation (P<0.05), while patient’s sex, age, duration of disease showed no statistically significant correlation with the recurrence (P>0.05). Multivariate logistic regression analysis revealed that the independent factors affecting recurrence included the number of used balloon≥2 (OR=7.80, 95%CI:2.28-26.73,P=0.001) and postoperative residual fistula that was observed immediately after the embolization (OR=10.46, 95%CI:2.99-36.50,P=0.000). Conclusion For the treatment of TCCF, transcatheter embolization with detachable balloon is minimally-invasive, safe and reliable with fewer complications, therefore, this technique should be regarded as the therapy of first choice. The use of multiple balloons and the presence of residual fistula observed immediately after the embolization procedure are the risk factors for recurrence. Other possible risk factors are still to be furtherstudied.
7.Effect of NaHS on IL-1β and IL-18 secretion in adipocytes and its mechanism
Tianxiao HU ; Gang WANG ; Qingying TAN ; Jing WANG
Chinese Journal of Endocrinology and Metabolism 2017;33(7):596-601
Objective To investigate the effect of hydrogen sulfide′s donor NaHS on the secretion of interleukin (IL)-1β and IL-18 in adipocytes and its mechanism.Methods 3T3-L1 cells were induced to differentiate into adipocytes and incubated with various concentrations of NaHS or 10 μg/ml caspase-1 inhibitor Ac-YVAD-CMK for 24 hours.The expressions of NLRP3(NLR family, pyrin domain containing 3), ASC(apoptosis associated speck-like protein containing CARD domain), caspase-1, IL-1β, and IL-18 in adipocytes, as well as the content of IL-1 and IL-18 in culture medium were determined.Results 10, 25, and 50 nmol/L NaHS significantly decreased NLRP3, ASC, and cleaved-caspase-1 protein expressions in adipocytes, as well as IL-1β and IL-18 contents in culture medium in a dose-dependent manner.The mature-IL-1β/pro-IL-1β, mature-IL-18/pro-IL-18 ratios in adipocytes and IL-1β and IL-18 contents in culture medium were also reduced by 10μg/ml Ac-YVAD-CMK.Conclusion Donor of hydrogen sulfide NaHS inhibits the maturation and secretion of IL-1β and IL-18 in adipocytes through downregulating the expression of NLRP3 inflammasome.
8.Long term follow up of carotid cavernous fistula patients treated with carotid occlusion
Weixing BAI ; Tianxiao LI ; Jiangyu XUE ; Ziliang WANG ; Li LI
Chinese Journal of Radiology 2012;46(10):921-924
ObjectiveTo explore efficacy,durability and possible impacts on life quality of carotid occlusion treatment to carotid cavernous fistula (CCF) patients.MethodsCCF patients since 2001 were retrospectively analyzed,the clinical features,2 weeks post procedure mRS score and ratio of carotid occlusion were recorded.Headache impact test (HIT-6) and Short form health survey(SF-36) were used to assess impact of sequelae in patients' daily life,by phone call,questionnaire and clinic recheck.Results Total 96 cases were studied composed of 81 direct CCF and 15 dural AVF.Thirty-two direct CCF cases underwent carotid occlusion during procedure and many ophthalmologic signs but visual impairment got recovery after 2 weeks,the mRS score less than 2 were revealed.The one year post operation HIT-6 score more than 50 was more likely found in carotid occlusion cases comparing with those preserved carotid artery while the 3 year SF-36 scores of carotid occlusion cases revealed inferior to those with patent artery,especially in body pain,general health and vitality subscales.ConclusionCarotid occlusion seems to be a feasible,effective and durable alternative for CCF treatment,but which could play a negative role on quality of patients' life in the long run.
9.Preliminary experience on early mechanical recanalization of middle cerebral artery for acute ischemic stroke and literature review
Weixing BAI ; Tianxiao LI ; Liangfu ZHU ; Jiangyu XUE ; Ziliang WANG
Chinese Journal of Radiology 2012;(11):1019-1022
Objective To evaluate the feasibility,efficacy and complication of early middle cerebral artery(MCA) mechanical recanalization(MER) for treatment of acute ischemic stroke.Methods Seven cases undergone MER of MCA for the treatment of acute cerebral infarct were retrospectively reviewed and analyzed,including the etiology,mechanism,Qureshi grading scale,location and size of infarcts,NIHSS score of pre and post procedure,endovascular technique and complications.Referring to the literature,the indications of MCA recanalization were further identified.Results A total of 7 cases with mean age of 48 yrs were reviewed,which included 3 cases of atherosclerotic thrombosis and 4 embolic cases with pre NIHSS score ranging from 3 to 22.Mechanical recanalization succeeded in 6 cases,but 2 cases of cardiogenic embolism died of intrac ranial hemorrhage postoperatively.Favorable clinical outcomes were achieved in 4 cases whereas 1 deteriorated.Overall complications seemed to be consistent with literatures reviewed.Conclusions Early MER of MCA may benefit to a certain subset of acute ischemia stroke patients,however,embolic cases,elder patients and those with severe neurologic deficits are often accompanied by higher complications and unfavorable outcome.
10.Prosapogenin A inhibits cell growth of MCF7 via downregulating STAT3 and glycometabolism-related gene.
Tianxiao WANG ; Xiaoyan SHI ; Yue CONG ; Zhongqing ZHANG ; Yinghua LIU
Acta Pharmaceutica Sinica 2013;48(9):1510-4
This study is to investigate the inhibitory effect and mechanism of prosapogenin A (PSA) on MCF7. MTT assay was performed to determine the inhibitory effect of PSA on MCF7 cells. PI/Hoechst 33342 double staining was used to detect cell apoptosis. RT-PCR was used to test the mRNA levels of STAT3, GLUT1, HK and PFKL. Western blotting was performed to determine the expression of STAT3 and pSTAT3 protein in MCF7 cells. The results showed that PSA could dose-dependently inhibit cell growth of MCF7 followed by IC50 of 9.65 micrmol x L(-1) and promote cell apoptosis of MCF7. Reduced mRNA levels of STAT3, HK and PFKL were observed in MCF7 cells treated with 5 micromol x L(-1) of PSA. PSA also decreased the level of pSTAT3 protein. STAT3 siRNA caused decrease of mRNA of GLUT1, HK and PFKL which indicated STAT3 could regulate the expressions of GLUT1, HK and PFKL. The results suggested that PSA could inhibit cell growth and promote cell apoptosis of MCF7 via inhibition of STAT3 and glycometabolism-related gene.