Study On The Effect And Molecular Mechanism Of Artesunate In Esophageal Cancer Cells

Esophageal cancer is one of the malignant tumors of the digestive system,which has two main histological subtypes:esophageal adenocarcinoma(EA)and esophageal squamous cell carcinoma(ESCC).It is also one of the most fatal malignancies worldwide,ranking seventh in terms of incidence and sixth in mortality overall.The geographic variation in esophageal cancer incidence is striking.China is one of the highest-risk areas,and 90%of cases are squamous cell carcinomas in China.High-throughput sequencing technology provides a good platform for understanding the genomic background of esophageal cancer.Statistical analyses of large-sample sequencing data show that ESCC has high mutation burden and heterogeneity.The most common alteration is the mutation of TP53 and there are also other gene mutations including CDKN2A.NOTCH1.NFE2LE and so on.The genetic alteration of esophageal cancer may be one of the most important reasons for which molecular targeted therapy progresses slowly in esophageal cancer.Therefore,better,economical chemotherapy drugs or adjuvant drugs are also good options to improve the efficacy of treatment and survival rates of esophageal cancer patients.Artemisinin is a sesquiterpene lactone isolated from the Chinese medicinal plant Sweet Wormwood(Artemisia annua L.,Asteraceae).It is discovered to be an effective antimalarial drug.In recent years,numerous hints were accumulated that activity of artemisinin is not restricted to malarial and that it may also be therapeutic for neoplasms,autoimmune disorders,virus infections and other diseases.Artesunate is one of the semisynthetic derivatives of artemisinin,and has higher activity than the latter one.It can also be activated in cancer cells with the cleavage of endoperoxide bridge,and form a quantity of reactive oxygen species and carbon-centered radicals,resulting in oxidative DNA damage,so that induces cell cycle arrest and cell apoptosis,and inhibits the proliferation of tumor cells finally.In our research,four esophageal squamous cancer cell lines(KYSE150,KYSE180,KYSE30,Eca109)were used.KYSE150 and KYSE180 is TP53 deficient and KYSE30 has CDKN2A stopgain mutation while Eca109 has wild-type TP53 and CDKN2A.Artesunate were performed to the esophageal cancer cells and induced oxidative DNA damage.In KYSE150 and KYSE180 cells,cyclinD1 decreased,and thus the activity of cyclinDl-CDK4/6 complex decreased,RB became hypo-phosphorylated,resulting in G1/S arrest and cells with DNA repair deficiency proceeded apoptosis.In KYSE30 cells,cells were pushed into S phase as p16-cyclinDl/CDK4-RB pathway was overactivated,but p53 pathway was also induced by DNA damage,resulting in G1/S arrest.These made the replication stress increase,and finally led to cell collapse.On the other hand,the wild-type Eca109 cell had unimpaired DNA damage repair pathway and cell cycle regulation,so it was less sensitive to the treatment of artesunate.The research also used Transcriptome Sequencing Technology to detect changes of transcriptome of esophageal cancer cells after the treatment of artesunate,exploring possible molecular mechanisms.And the effect of artesunate towards esophageal cancer cells was confirmed by in vivo investigation using KYSE150 xenografts transplanted to nude mice.In conclusion,artesunate,which was an antimalarial drug developed by Chinese scientists exerted inhibitory activity against esophageal cancer in vivo and in vitro by inducing cell apoptosis and cell cycle arrest through oxidative DNA damage.It provided a potential option for clinical application as a chemotherapeutic or adjuvant drug for esophageal cancer.