Oncology Letters
·
2018
·Vol. 15
·期 4
·5250-5256
·
IF 1.664
Jun‑Ming Chen,Jue Zhang,Yong‑Mei Xia,Xiao‑Xia Wang,Jian Li
Steviol is the colonic metabolite of the natural sweetener steviol glycosides. It does not diffuse to the blood and the half maximal inhibitory concentration of steviol is longer compared with that of current chemotherapy agents, including 5‑fluorouracil and doxorubicin. The present study demonstrated that steviol inhibits the proliferation of the human osteosarcoma U2OS cell line in a dose‑ and time‑dependent manner, and that the inhibition rate is comparative with that of doxorubicin and 5‑fluorouracil. The mechanism of this anticancer activity is also investigated. The results indicated that steviol inhibits U2OS cells through inducing G1 phase cell cycle arrest, downregulating the ability of colony formation via a mitochondrial apoptotic pathway, which was indicated by an increase of the Bax/Bcl‑2 ratio and activation of cyclin‑dependent kinase inhibitor 1, tumor protein 53 and cyclin‑dependent kinase; whereas a Survivin and Caspase 3‑independent mechanism was involved. Considering that steviol appears minimally in the plasma during metabolism, and possesses a median lethal dose of 100-fold greater compared with that of 5‑fluorouracil, it may become a potential chemotherapy agent.
研究领域:
肿瘤学
·
药理学
·
代谢
✓ 已验证
DOI
PubMed
高影响因子
Nanoscale
·
2018
·Vol. 10
·期 18
·8796-8805
·
IF 7.233
Yimin Wang,Zhao Zhao,Fujing Wei,Zewei Luo,Yixiang Duan
Autophagic degradation of the endoplasmic reticulum (ER-phagy) has been found to play a critical role in human sensory neuropathy. So far, however, specific and efficient intervention means for ER-phagy remain unexplored. Herein, brefeldin A (BFA), a blocking agent on protein transport between the ER and Golgi, was screened from ER stress inducers. BFA was then delivered to the perinuclear area co-localized with the ER by a mesoporous silica nanoparticle-based drug-carrier functionalized with autophagy-inducing peptides of TAT-beclin 1 (MSNs-BFA), to evoke a perturbation of ER-phagy. The molecular mechanism of ER-phagy regulated by BFA was explored by biochemical evaluation including time-lapse live-cell fluorescence imaging. We found that MSNs-BFA treatment caused a lower mRNA/protein expression level of FAM134b even under a compensation of autophagic flux in U2OS cells, and resulted in ER-expansion. The fragmentation of the ER was blocked as a response to ER stress mediated by inactivation of the AKT/TSC/mTOR pathway. Our work developed an efficient external manipulation strategy to regulate ER-phagy and may contribute to the therapeutic application of autophagy-related major human diseases.
研究领域:
细胞生物学
·
分子生物学
·
药学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FASEB JOURNAL
·
2021
·Vol. 35
·期 10
·e21923
·
IF 5.192
Peiling Wang,Xiangmei Hua,Yang Sun,Hongyu Li,Yuge Han Bryner,Richard P. Hsung,Jun Dai
Our recent studies have shown that haspin, a protein kinase imperative for mitosis, is engaged in the interphase progression of HeLa and U2OS cancer cells. In this investigation, we employed the Fucci reporter system and time-lapse imaging to examine the impact of haspin gene silencing on cell cycle progressions at a single-cell level. We found that the loss of haspin induced multiple cell cycle defects. Specifically, the S/G2 duration was greatly prolonged by haspin gene depletion or inhibition in synchronous HeLa cells. Haspin gene depletion in asynchronous HeLa and U2OS cells led to a similarly protracted S/G2 phase, followed by mitotic cell death or postmitotic G1 arrest. In addition, haspin deficiency resulted in robust induction of the p21 CIP1/WAF1 checkpoint protein, a target of the p53 activation. Also, co-depleting haspin with either p21 or p53 could rescue U2OS cells from postmitotic G1 arrest and partially restore their proliferation. These results substantiate the haspin's capacity to regulate interphase and mitotic progression, offering a broader antiproliferative potential of haspin loss in cancer cells.
研究领域:
癌症生物学
·
细胞生物学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Analytical Methods
·
2019
·Vol. 11
·期 42
·5398-5404
·
IF 2.378
Shengting Zhang,Mingrui Li,Dongbo Liu,Kunhao Qin,Yingying Xiang,Xiuling Ji,Congwen Li,Yunlin Wei
The human purinergic P2Y1 receptor (P2Y1R) belongs to the family of G-protein coupled receptors (GPCRs). Two stable cell lines, hP2Y1R-tGFP/U2OS and hP2Y1R-β-AR2-tGFP/U2OS, were generated with steady expression of fluorescent tGFP tagged P2Y1R or tGFP tagged β-arrestin2. The High Content Screening (HCS) technique was used to investigate P2Y1R mediated signal transduction processes based on the distribution of fluorescent receptors or the β-arrestin2/receptor complex. All procedures including aggregation, endolysis and resensitization that were involved in the interaction between the P2Y1 receptor and its ligand can be visualized using the tGFP labeled receptor combined with HCS technology in this study. ADP activated P2Y1R to induce a distinguished pattern of fluorescent vesicle formation inside both cell types. These two cell lines produced different peak fluorescence signals when activated by ADP at 100 μM, and the time to form the maximal vesicles was detected as 15 and 20 min respectively. The EC50 values of the concentration–response curves of ADP induced formation of fluorescent vesicles were 35.7 nM and 71.8 nM respectively. The ADP effects could be blocked by a P2Y1R specific antagonist MRS2179. The P2Y1R are coupled to Gq protein to activate PLC first, PLC cleave PIP2 into IP3 and DAG. And then DAG and Ca2+ activate PKC pathway, and finally the phospholipase D initiates β-arrestin2 mediated signal pathway. It took 30 and 45 min to complete P2Y1R re-sensitization in these two constructs respectively. Our results demonstrated that P2Y1R triggered downstream responses not only via heterotrimeric Gq proteins but also through β-arrestin2.
研究领域:
细胞生物学
·
药理学
·
分子生物学
·
信号转导
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）