Study On The Regulation Of TGF-β-Induced Invasions And Epithelial-interstitial Metastasis Of Non-Small Cell Lung Cancer Cell By Farnicyl Pyrophosphate Synthase

Background & Objective: Lung cancer is one of the most common types of cancer.Non-small cell lung cancer(NSCLC)is the main form of lung cancer and the world’s deadliest cancer.There is evidence that inhibiting NSCLC cell metastasis can reduce mortality in patients.The mevalonate pathway is involved in every link of tumor‘s development and progression,and farnesyl pyrophosphate synthase(FPPS)is a key enzyme in this process.In this study,we explored the potential role of FPPS in the genesis and progression of NSCLC tumors.It was confirmed that the expression of FPPS was significantly correlated with the tumor node metastasis(TNM)stage and metastasis of NSCLC,and FPPS mediated TGF-β1-induced NSCLC cell invasion and EMT through Rho A/ ROCK1 pathway.On the basis of this study,we further explored the correlation between the expression of lnc RNA MALAT1/Exo-MALAT1 and TNM staging and metastasis of NSCLC,as well as the mutual regulation mechanism between MALAT1/Exo-MALAT1 and FPPS through the mi R142-3p/GARP pathway.we investigated the potential role of FPPS in NSCLC tumorigenesis.It was confirmed that the expression of lnc RNA MALAT1 was significantly correlated with TNM staging and metastasis of NSCLC,and MALAT1 interregulated with FPPS through the mi R142-3p/GARP pathway.It is revealed that FPPS may combine with transcription factors to regulate lnc RNA MALAT1,which can be used as a new experimental method to search for the transcriptional regulation of lnc RNA in NSCLC.Methods: We detected the expression of FPPS by RT-q PCR in tumor specimens.At the same time,RT-q PCR,Western blot and Transwell tests were performed on lung cancer cell lines to detect the expression of FPPS and cell invasion ability.In addition,FPPS gene silenced and overexpressed cell models were constructed.TGF-β1-induced cell invasion and EMT were blocked by FPPS inhibitor or lentivir-mediated sh RNA specific interference with NSCLC cell FPPS gene.FPPS overexpression significantly enhanced the invasion ability of NSCLC and promoted the occurrence of EMT,suggesting that FPPS plays a key role in TGF-β1-related NSCLC metastasis.In addition,the present study detected that Rho A-specific sh RNA or ROCK1 inhibitor significantly inhibited TGF-β1 or FPPS induced cell invasion and EMT by Western blot assay,indicating that FPPS can regulate the activation of TGF-β1 on Rho A/ROCK signaling pathway.The expression of lnc RNA MALAT1 was detected by RT-q PCR in tumor specimens of clinical patients.At the same time,RT-q PCR,Western blot and Transwell tests were performed to detect the expression of MALAT1 and the cell invasion ability in the lung cancer cell lines.The cell lines with high expression of MALAT1 had high invasion ability.We collected the supernatant of culture medium of cancer cells,and collected and purified EVs secreted by lung cancer cells by hypercentrifugation method.The size and number of EVs were analyzed by Transmission electron microscopy(TEM)and Nanoparticle tracking analysis(NTA),and then the exosome lnc RNA MALAT1 levels of the cell lines were determined.In addition,in order to verify whether FPPS regulates MALAT1,we performed Ch IP assay with FPPS antibodies.The results showed that FPPS could bind to the promoter region of MALAT1 and mediate the regulation of the MALAT1/mi R-142-3p signaling pathway.The role of MALAT1 in lung cancer exosomes in TGF-β1-induced invasion and EMT increase by regulating mi R142-3p/GARP was verified by RT-q PCR.Results:(1)The expression of FPPS and lnc RNA MALAT1 in tumor cells was significantly higher than that in normal cells,and the invasion power was also significantly higher than that in normal cells.(2)The expression level of FPPS and lnc RNA MALAT1 was significantly correlated with TNM stage and metastasis of NSCLC,and was independent of other clinical factors such as age,tumor site and tumor size.(3)TGF-β1 can induce FPPS expression in NSCLC cells;(4)In gene-silenced cell models,inhibition or knockdown of FPPS can inhibit TGF-β-mediated cell invasion and EMT;(5)FPPS promoted invasion and EMT of NSCLC cells through Rho A/ ROCK1 pathway;(6)The expression of MALAT1/MALAT1-Exo in cell lines with higher invasion ability was correspondingly higher;(7)MALAT1-Exo derived from lung cancer cells can increase the invasion and EMT of TGF-β1-mediated lung cancer cells;(8)Farnesyl pyrophosphate synthase(FPPS)knockdown blocked was treated with LC cell-derived exosomes,increased TGF-b1-induced cell invasion and EMT;(9)MALAT1 interacts with FPPS in lung cancer cell lines;(10)FPPS induces invasion and EMT of lung cancer cells through MALAT1/mi R-142-3p pathway.Conclusion: Our study showed that the expression of FPPS in NSCLC tumor cells was significantly higher than that in normal cells,and the invasion power was also significantly higher than that in normal cells.FPPS promotes invasion and EMT of NSCLC cells through Rho A/ROCK1 pathway and MALAT1/mi R-142-3p pathway.Our study showed that the expression of lnc RNA MALAT1 in NSCLC tumor cells was significantly higher than that in normal cells,and the invasion power was also significantly higher than that in normal cells.MALAT1-Exo secretion was correspondingly higher in the more invasive cell lines.FPPS may bind transcription factors to regulate lnc RNA MALAT1,which can be used as a new experimental method to investigate the transcriptional regulation of lnc RNA in NSCLC.