The Expression Of Carbamoyl(?)Phosphate Synthase 1 And Carbamoyl-Phosphate Synthase 1 Intronic Transcript 1 Were Co? Upregulated In ICC And Correlated With Poor Prognosis

Background: Intrahepatic cholangiocarcinoma(ICC)with higher metastasis rate and postoperative recurrence rate,also known as cholangiocarcinoma(CCA).That's why ICC is considered as one kind of highly malignant tumor in clinical work.Most reasearchs confirmed that ICC is derived from the covering epithelium of the intrahepatic bile duct.However,its pathogenesis is still being more controversy.At present,most of the tumor markers for ICC are lack of specificity and sensitivity,so there are still many difficulties for the diagnosis and evaluating the prognosis of patients with ICC.In recent years,the studies of pathogenesis and prognosis of ICC are becoming worldwide focus.On the other side,long non-coding RNA(lnc RNA)has been confirmed that they play important roles in many aspects in lot of recent studies,such as epigenetic modification,transcription and translation regulation,cell cycle regulation and differentiation,apoptosis regulation.It is worth noting that lnc RNAs also play very important roles in tumorigenesis.However,it is still lack of related researches about lnc RNAs' expression and the specific mechanism in ICC.The purpose of this study lies in three aspects: Firstly,selected a series of genes or lnc RNAs which significantly highly expressed in ICC by bioinformatics.Secondly,singled out genes or lnc RNAs which may have more significance and then verified its expression in ICC tissues and cell lines.At last,we searched its important effects on the biology behavior and clinicopathological features of ICC.Methods: In this study,the expression of 19850 genes and 5635 kinds of lnc RNAs were analyzed with ICC tissue microarray using bioinformatics.The data showed that: the gene of carbamoyl-phosphate synthase 1(CPS1)and its lnc RNA-carbamoyl-phosphate synthase 1 intronic transcript 1(CPS1-IT1)were co-upregulated in ICC tissues.It was worth noting that there was a significant correlation between the expression of CPS1 and CPS1-IT1.Secondly,the expression levels of CPS1 and CPS1-IT1 in 31 tissues of ICC patients and different kinds of liver cell lines were tested using reverse transcription real-time quantitative polymerase chain reaction,Western-blot,immunohistochemistry,RNA interference,immunofluorescence,flow cytometry and other relevant experiments.The effects of CPS1 and CPS1-IT1 on proliferation and apoptosis of ICC cell line(ICC-9810)were also determinated.Finally,the correlations of the CPS1 gene,CPS1-IT1 with clinicopathological features,postoperative disease-free survival rate and overall survival rate of ICC patients were analyzed,combining with the clinical data of the ICC patients.Results: There was a rising trend of the CPS1 m RNA expression in cancer tissues compared with the non-tumorous tissues(P=0.09).And the expression of CPS1-IT1 in cancer tissues was significantly increased compared with the non-tumorous tissues(P=0.001).The relative expression of CPS1 m RNA and CPS1-IT1 were both significantly increased compared with non-tumorous tissues(all of the P values were < 0.001).Consistently,the results of immunohistochemistry and Western-blot showed that CPS1 protein was highly expressed in ICC cancer tissues.Reducing the expression level of CPS1 and(or)CPS1-IT1 in the ICC-9810 cell line by RNA interference could promote the cell proliferation and decrease the apoptosis(P<0.001).The results of the clinical data analysis indicated that: When the expression of CPS1 or CPS1-IT1 in ICC cancer tissues were 4-5 times more than the expression of non-tumorous tissues,they might have significant impact on the postoperative survival rate of patients with ICC.When using "Four times" as the boundary to divide the CPS1 or CPS1-IT1 high expression group and the low expression group,CPS1 could affect the international normalized ratio(INR)of ICC patients(P=0.048),serum total protein level(P=0.049),serum indirect bilirubin level(P=0.025)and postoperative disease-free survival(P=0.034)significantly,and it also had an impact trends on serum total bilirubin level(P=0.066)and carbohydrate antigen 19-9(CA19-9)positive rate(P=0.068);CPS1-IT1 could affect the positive rate of lymph node invasion(P=0.045),CA19-9 positive rate(P=0.044)and postoperative disease-free survival rate(P=0.026)significantly,and had an impact trends on postoperative overall survival rate(P=0.064)Conclusion: CPS1 and CPS1-IT1 were both highly expressed in ICC cancer tissues,and they could promote the proliferation and decrease the apoptosis of ICC-9810.So CPS1 and CPS1-IT1 might play an important role in occurrence and development of ICC by affecting the proliferation and apoptosis of ICC cells.And they might become the relatively specific tumor markers of ICC on clinical diagnosis,and they might provide a new effective targets for its treatment.In addition,there correlations between the expression of CPS1,CPS1-IT1 and liver function,postoperative disease-free survival rate and overall survival rate significantly.They both might become the important indices for evaluating the prognosis of patients with ICC.