Preliminary Study On The Pathological Changes And Mechanism Of Arsenic-induced MiR-100 Inactivation In Mice And MEFs

Lung cancer is a cancer with high morbidity and mortality worldwide,and the mechanism is unclear.The molecular mechanism of tumorigenesis is very complex and requires the combined effects of environmental and genetic factors.Among them,mi RNA is one of the newly discovered major molecules that may be involved in the development of many diseases including tumors.Our laboratory has been committed to studying genetic and the influence of environmental factors on tumorigenesis and development.mi R?100 is a type of micro RNA?micro RNA,mi RNA?,a type of non?coding single?stranded small?molecule RNA with a size of approximately 22 nucleotides.Existing research confirms that mi RNAs play an important role in the occurrence and development of cancer,and according to the different target genes,mi RNAs are classified into mi RNAs with biological activity of oncogenes or tumor suppressor genes.Previous studies have shown that mi R?100 is down?regulated in non?small cell lung cancer.In addition to genes,the environment is also an important factor in the development of cancer.Arsenic?As?is a heavy metal pollutant that can be widely exposed through daily activities such as water,food,soil,and polluted air,including smoking.When ingested through drinking water,the biotransformation of pentavalent arsenic in the body causes it to produce arsenic substances with high carcinogenic potential,which then leads to mitochondrial dysfunction,changes in micro RNA expression,changes in DNA methylation,etc.Cause changes in genetic and epigenetic levels.At present,heavy metal arsenic has been identified as a carcinogen internationally.So we put forward the following hypothesis:Can heavy metal arsenic cause certain pathological changes in the lungs of mi R?100 inactivated mice?If yes,what is the mechanism??Methods?1.In vitro experiment?1?Prepare MEF(mi R?100^flox/flox)and MEF(mi R?100^?/?)cells,and then transfect SV40T lentivirus to establish immortalized cell lines.?2?The two cells were treated with 100 nmol/L As₂O₃ for a long time to obtain two induced cell models.?3?The effects of arsenic induc on on the malignant behavior of two MEF cells were tested by Ki?67,transwell,and plate cloning experiments.2.In vivo experimentFirst,a mouse model of mi R?100 systemic knockout was established,and then mice with mi R?100^flox/flox and mi R?100^flox/flox EIIa?Cre genotypes were treated with 100ppm As₂O₃ in drinking water to monitor the water consumption and weight,observe their vital signs,and kill them after a period of time,take the lungs and other parts of the mice for pathological section analysis to determine whether the addition of arsenic induces pathological changes in the lungs of mi R?100 inactivated mice.?Results?1.Established a mouse model of mi R?100 systemic knockout.2.Two immortalized cell lines of MEF cells were successfully obtained,and a heavy metal arsenic?induced cell model was successfully established.3.The experimental results of Ki?67,transwell,plate cloning,etc.showed that the induction of arsenic promoted mi R?100?inactivated MEF cell migration,invasion and proliferation ability,that is,malignant transformation.4.mi R?100^?/?genotype mice undergo pathological changes under arsenic induction.?Conclusion?As₂O₃ caused malignant behavioral changes in the mi R?100 inactivated cells,and pathological changes in the lungs of the mi R?100 inactivated mice.