Pharmacodynamic Effect Of Dihydroartemisinin On Head And Neck Cancer

BackgroundHead and neck cancer is one of the most common malignant tumors,which has the characteristics of high malignancy and extensive invasion,so the recurrence and mortality rate is high.Surgery and radiotherapy are the main methods for the treatment of early and locally advanced head and neck tumors.Cisplatin or cetuximab combined with radiotherapy is the first choice for concurrent chemotherapy.Overexpression of EGFR in head and neck cancer is associated with poor overall survival and progression free survival.Cetuximab is the only head and neck cancer targeted drug approved by FDA,but the existing test results are not enough to replace the status of standard chemoradiotherapy.Cisplatin,as the first-line drug for head and neck cancer,its intrinsic resistance and acquired resistance are relatively common,and accompanied by more serious side effects.Cisplatin resistance is the result of multiple factors,mainly involving drug accumulation,metabolism,DNA damage repair and other aspects.In recent years,researchers have found that Signal transducers and activators of transcription 3(STAT3)plays an important role in cisplatin resistance,so STAT3 may be a potential therapeutic target for head and neck cancer.Dihydroartemisinin(DHA)is a first-line drug for malaria,which is recognized worldwide.It is highly effective,safe,well tolerated and widely used in clinic.In addition to anti malaria and anti bloodsucker disease,it has been proved that many types of tumor cells have significant inhibitory effect.Previous laboratory studies have found that DHA is a good STAT3 inhibitor,which can inhibit the activation of STAT3 induced by EGFR targeted drugs in non-small cell lung cancer,and play the role of sensitizing targeted drugs.ObjectiveTo explore the possibility of DHA as a STAT3 inhibitor in head and neck cancer:1.To clarify the inhibition of DHA on STAT3 activation induced by cisplatin and enhance the efficacy of cisplatin against head and neck cancer;2.To explore the combined efficacy of DHA and EGFR tyrosine kinase inhibitor Osimertinib in inhibiting head and neck cancer.MethodsFirstly,the effects of DHA on head and neck squamous cell carcinoma cell were studied through in vitro pharmacodynamic experiments,such as MTT,Annexin V-PE/7AAD apoptosis detection method and flow cytometry of PI cycle detection method,and Western Blot and q-PCR were used to detect the expression status and mRNA level of related proteins.Useing public databases to conduct bioinformatics analysis of STAT3 characteristics in head and neck cancer,and useing siRNA to target interference with STAT3 to further explore the role of STAT3.To construct HNSCC cell derived xenograft tumor models(CDX)and patient-derived tumor xenograft(PDX),in vivo verification of DHA and its effect in combination with cisplatin and osimertinib.ResultsDHA inhibited the proliferation and apoptosis of HNSCC cell lines in a concentration-dependent manner,and arrested the cells in G0/G1 phase with the decrease of S phase;DHA inhibits both constitutive and inducible(IL-6 and DDP induced)phosphorylation of STAT3.The results of public database analysis showed that STAT3 was highly expressed in head and neck cancer,and was related to disease-free survival.Compared with DDP group,siRNA targeting STAT3 can further induce apoptosis.The combination of DHA and DDP,a potential inhibitor of STAT3,could significantly inhibit the proliferation of HNSCC cell lines;In vivo CDX and PDX model experiments,the tumor volume of the combination group was significantly lower than that of the control group.H&E staining found that a lot of liver metastases occurred in the PDX model group,and the DDP single group had no obvious inhibitory effect on the metastasis,while the DHA combined with cisplatin group could reduce the liver metastasis.The blood biochemical indexes also showed that the liver function indexes of DDP group were abnormally increased,and the DHA combined with cisplatin group can improve this situation.DHA can further inhibit the proliferation of HNSCC cells when combined with oxitinib.At the same time,DHA can inhibit the activity of kinase related to osimertinib resistance,such as STAT3,MET and AXL,but it will not affect the inhibitory effect of osimertinib on EGFR in head and neck cancer cells.in vivo pharmacodynamic experiment results show that compared with the control group,the combined group can significantly inhibit the growth of head and neck tumors.ConclusionDHA can inhibit the proliferation of HNSCC cells through STAT3,block the cells in G0/G1 phas with the decrease of S phase,and then affect cell viability and induce apoptosis.Targeting STAT3 can enhance the sensitivity of head and neck cancer cells to cisplatin,which indicates that STAT3 is closely related to the occurrence and development of head and neck tumor and even chemotherapy resistance.The combination of DHA and DDP can further enhance the apoptosis-inducing effect on HNSCC cells,and the synergistic sensitization was also verified by CDX and PDX models in vivo.We also investigated the possibility of DHA combined with ERFR small molecule inhibitor osimertinib applied to the possibility of head and neck cancer.They can further inhibit the kinase activity related to the resistance of osimertinib and delay the drug resistance.In vivo experimental results showed that the combination group can significantly inhibit the growth of head and neck cancer compared with the control group,and they have a synergistic sensitization effect.