MYST2 Affects The Biological Function Of Lung Adenocarcinoma Cells By Regulating P38MAPK Signaling Pathway

BackgroundLung cancer is one of the fastest growing morbidity and mortality rates,and the most threatening to the health and life of the population.Because early lung cancer is more insidious,it is not easy to check the diagnosis.Most patients are diagnosed in the late stage,often accompanied by local spread or lymph node metastasis.Early diagnosis and treatment can effectively prevent the metastasis of lung cancer,which can prolong the survival time of patients and improve the quality of life of patients.At present,in the treatment of lung cancer,although great progress has been made through targeted drug therapy,the treatment effect on lung adenocarcinoma and lung squamous cell carcinoma is still not ideal.Therefore,it is an urgent problem to explore related molecular mechanisms in the process of lung cancer development and identification of more effective early diagnosis markers and therapeutic targets for lung cancerThe histone acetyltransferase MYST protein family is curently found to have five members Myst1/Mof/Kat8/sas2,Myst2/Hbol/Kat7,Myst3/Moz/Kat6a/sas3,Myst4/Morf/Kat6b,Tip60/Kat5/Esa1.These proteins all contain the MYST domain(acetyltransferase domain at the acetyl-CoA binding site),which can bind to acetyl-CoA and be responsible for the acetylation modification of histones.As an important member of the MYST protein family,histone acetyltransferase MYST2 has a variety of biological functions,mainly including promoting gene transcription and DNA replication,participating in protein ubiquitination modification and immune regulation,regulating embryonic development,regulating stem cell Capability and self-renewal of stem cells,etc.Existing studies have found that MYST2 is highly expressed in breast cancer,bladder cancer,stomach cancer,esophageal cancer,testicular cancer and ovarian cancer,which is closely related to the occurrence and development of cancer.In breast cancer,MYST2 mediates estrogen receptor(ER?)proteasome degradation through ubiquitination,thereby promoting the proliferation of breast cancer cells.In bladder cancer,MYST2 promotes the proliferation of bladder cancer cells by activating the Wnt/world-catenin signaling pathway.However,there are few reports on the research of MYST2 in lung cancer.Based on the previous analysis of TCGA database,we found that MYST2 was highly expressed in lung adenocarcinoma.Therefore,it is necessary to further study the influence of MYST2 on the occurrence and development of lung cancer and its molecular mechanism,so as to explore the feasibility of MYST2 as a new target for the diagnosis and treatment of lung cancer.AimBy constructing MYST2 knockout and overexpressing lung adenocarcinoma cell lines to explore the effect and molecular mechanism of MYST2 on the biological function of lung adenocarcinoma cells.MethodsMYST2 knockout in NCI-11299 cell line and MYST2 overexpression in A549 cell line were constructed,and the overexpression and knockout effect of MYST2 were verified by Western blot experiments.Through in vitro functional experiments,such as plate cloning experiment,scratch experiment,Transwell experiment,invasion experiment,cell cycle experiment,apoptosis experiments,to study the effect of MYST2 on the biological function of lung adenocarcinoma cells.Western blotting was used to detect the phosphorylation of proteins related to cell growth,differentiation and death.The interaction between MYST2 and related proteins was detected by Co-IP experiments,and truncated plasmids of MYST2-TV1/TV2 were constructed,and the key domains of interaction between MYST2 and target proteins were detected by Co-IP experiments.GST pull-down experiments were used to detect whether MYST2 directly interacted with related proteins,and explore how MYST2 regulates protein binding to affect the phosphorylation of target proteins.ResultsFirst,Western blot was used to detect the protein expression levels in the cells.The results showed that we successfully established MYST2 overexpression cell lines and knockout cell lines.Through plate cloning experiment,scratch experiment and Transwell experiment,it found that MYST2 promoted the cloning ability,migration ability and invasion ability of lung adenocarcinoma A549 and NCI-H1299 cells;through cell cycle experiment and apoptosis experiment,it was found that MYST2 did not affect A549 And NCI-H1299 cell cycle and apoptosis.In addition,through Western blot,it was found that knocking out MYST2 down-regulated the phosphorylation level of p38 and ERK.Co-IP experiments show that MYST2-TV1/TV2 interacts with p38 through the MYST domain.GST pull-down experiments show that there is no direct interaction between MYST2-TV1/TV2 and p38,MYST2-TV1/TV2 regulates the phosphorylation of p38 by promoting the binding of MEK6 and p38,and MYST2-TV1 promotes the combination of MEK6 and p38 through the MYST domain.Gradient transfection of MYST2-TV1/TV2 plasmid,and then Western blot experiments found that MYST2-TV1/TV2 does not directly affect the expression of MEK3 and MEK6Conclusion1.Histone acetyltransferase MYST2 promotes the growth,migration and invasion of lung adenocarcinoma cells.2.MYST2 promotes the binding of MEK6 and p38 through the MYST domain to regulate p38 phosphorylation,activate the p38MAPK signaling pathway,and thus affect the biological function of lung adenocarcinoma cells.