KIAA1199 Expression Is Associated With Acquisition Of EMT Phenotype And With Enhanced Invasion In HCC Sorafenib Resistant Cells

Background Hepatocellular carcinoma(HCC)is one of the most prevalent malignancies and is the third leading cause of cancer death worldwide.Nearly per million people die of this disease per year.However,the incidence of HCC has increased steadily and 5-year survival rate was still low,despite successful therapies such as surgery,transcatheter arterial chemoembolization,radiation and chemotherapy,patients with HCC develop a high rate of recurrence and metastasis.These studies have showed that the interaction between internal and external factors has a crucial effect on tumor biological behaviors including recurrence,metastasis and drug resistance.Therefore,if we can find and design the key targeted therapeutic targets will has a great significance to improve the therapeutic effects.Sorafenib is the first and only targeted therapy clinically improved overall survival in patients with advanced HCC.However,most patients who initially responded to treatment with sorafenib relapsed,suggesting that chronic treatment with sorafenib is associated with development of drug resistance.In the current study,we have established HCC sorafenib-resistant cell models for further investigate the molecuar mechanisms of sorafenib resistance.Our m RNA expression array analysis revealed that KIAA1199 was significantly up-regulated in sorafenib-resistant cells,compared with their parental cells.These data were suggested that KIAA1199 may plays an important role in regulation of sorafenib resistance in HCC cells.So we next used sorafenib-sensitive and-resistant cell models to comprehensively investigate the role of KIAA1199,as well as potential molecular machines.Objective: To investigate the role of KIAA1199 in HCC sorafenib cells,and reveal the molecular mechanisms.Our results may provide the theoretical basis for reversal sorafenib resistance in clinical medicine.Method: We firstly established sorafenib-resistant cell models Huh7-DR and PLC-DR by intermittent induced methods.Then,we depleted the 153 KDa KIAA1199 expression in HCC sorafenib-resistant cells using RNA interference,and explore the effect of KIAA1199 on migration and invasion of HCC sorafenib-resistant cells.Furthmore,we depleted the 110 k Da KIAA1199 expression in HCC cell lines Huh7 and PLC using RNA interference,and detected the role of KIAA1199 in proliferation of HCC cells.Results: Our results indicated that we have successfully established HCC sorafenib-resistant cells Huh7-DR and PLC-DR with strong tolerant and high stability.our data also showed that the growth capability and the colony formation efficiency of sorafenib-resistant cells was slightly lower than their counterparts cells.Moreover,we found that 153 k Da KIAA1199 splice variant and ABCC1 were significantly up-regulated in sorafenib-resistant cells compared with their parental cells.Importantly,sorafenib-resistant cells were acquired the EMT phenotype and enhanced invasion compare to their parental cells,which accompany by epithelial markers E-cadherin,Occluding and Zo-1 significantly down-regulated and mesenchymal-like markers Vimentin significantly up-regulated.We depleted the 153 k Da KIAA1199 expression in HCC sorafenib-resistant cells using Lv-sh-KIAA1199(153 k Da),the sorafenib-resistant cells were occurred MET development,which accompany by epithelial markers E-cadherin,Occluding and Zo-1 significantly up-regulated and mesenchymal-like markers Vimentin significantly down-regulated.Moreover,the capacity of migration and invasion was obviously reduced in sorafenib-resistant cells when knock-down the 153 k Da KIAA1199 expression.In addition,we depleted the110 k Da KIAA1199 expression in HCC cell lines Huh7 and PLC by Lv-sh-KIAA1199(110 k Da),which was effectively inhibit the cell proliferation,colony formation efficiency in vitro and tumorigenicity in vivo.Conclusions: The KIAA1199 protein contains two splice variants of 153 k Da and 110 k Da,the 153 k Da KIAA1199 is necessary for acquisition of EMT phenotype in HCC sorafenib-resistant cells,the 110 k Da KIAA1199 plays a crucial role in HCC cells proliferation.