Effect of long non-coding RNA EIF3J-AS1 on multi-drug resistance and autophagy in gastric cancer.

2017 ◽  
Vol 35 (15_suppl) ◽  
pp. e15581-e15581
Author(s):  
Yuhao Luo ◽  
Rui Zhou ◽  
Na Huang ◽  
Li Sun ◽  
Wangjun Liao

e15581 Background: Gastric cancer (GC) is a leading cause of cancer mortality worldwide, oxaliplatin and epirubicin based chemotherapy are one of the most important treatment options for GC patients. However, drug resistance, especially multi-drug resistance remains a major obstacle for successful chemotherapy. Recently, long non-coding RNAs (lncRNAs) have been widely identified to play emerging roles in diverse physiological and pathophysiological processes including drug resistance. Our previous bioinformatics analysis showed long non-coding RNA EIF3J-AS1 was a potential multi-drug resistance gene, but the underlying mechanism is still unknown. Methods: We generated oxaliplatin resistance cells (MGC803/OXA) and epirubicin resistance cells(MGC803/EPI) based on parental gastric cancer cells MGC803. Relative expression levels of EIF3J-AS1 were measured by qRT-PCR. Transmission electron microscopy was used to measure autophagosomes. Rapamycin was applied to inducing autophagy while chloroquine and 3-methyladenine were used to block autophagy. Protein level of autophagy related genes were examined by Western Blot. Coexpression genes of EIF3J-AS1 from TCGA RNA-seq datas were analyzed by cBiportal. RNA immunoprecipitation was used to analyze endogenous microRNAs and mRNAs. Results: EIF3J-AS1 was significantly upregulated in MGC803/OXA and MGC803/EPI cells compared with parental cells MGC803. EIF3J-AS1 inhibition increased chemosensitivity to both oxaliplatin and epirubicin. Moreover, EIF3J-AS1 silence lead to the decrease of autophagy. Autophagy related gene ATG14 was identified as a downstream target gene. EIF3J-AS1 promoted ATG14 expression by directly interacting with and increasing stability of ATG14 mRNA, On the other hand, EIF3J-AS1 competitively sponged miR-188-3p and promoted ATG14 expression in a ceRNA-dependent way. Conclusions: LncRNA EIF3J-AS1 is a crucial regulator of multi-drug resistance by inducing autophagy in gastric cancer. Targeting EIF3J-AS1/ATG14 axis might be a new paradigm for cancer therapeutics.

Author(s):  
Zhifu Gui ◽  
Zhenguo Zhao ◽  
Qi Sun ◽  
Guoyi Shao ◽  
Jianming Huang ◽  
...  

Long non-coding RNAs (lncRNAs) play important roles in human cancers including gastric cancer (GC). Dysregulation of lncRNAs is involved in a variety of pathological activities associated with gastric cancer progression and chemo-resistance. However, the role and molecular mechanisms of FEZF1-AS1 in chemoresistance of GC remain unknown. In this study, we aimed to determine the role of FEZF1-AS1 in chemoresistance of GC. The level of FEZF1-AS1 in GC tissues and GC cell lines was assessed by qRT-PCR. Our results showed that the expression of FEZF1-AS1 was higher in gastric cancer tissues than in adjacent normal tissues. Multivariate analysis identified that high level of FEZF1-AS1 is an independent predictor for poor overall survival. Increased FEZF1-AS1 expression promoted gastric cancer cell proliferation in vitro. Additionally, FEZF1-AS1 was upregulated in chemo-resistant GC tissues. The regulatory effect of FEZF1-AS1 on multi-drug resistance (MDR) in GC cells and the underlying mechanism was investigated. It was found that increased FEZF1-AS1 expression promoted chemo-resistance of GC cells. Molecular interactions were determined by RNA immunoprecipitation (RIP) and the results showed that FEZF1-AS1 regulated chemo-resistance of GC cells through modulating autophagy by directly targeting ATG5. The proliferation and autophagy of GC cells promoted by overexpression of LncFEZF1-AS1 was suppressed when ATG5 was knocked down. Moreover, knockdown of FEZF1-AS1 inhibited tumor growth and increased 5-FU sensitivity in GC cells in vivo. Taken together, this study revealed that the FEZF1-AS1/ATG5 axis regulates MDR of GC cells via modulating autophagy.


2020 ◽  
Vol 11 ◽  
Author(s):  
Yingying Kou ◽  
Bending Tong ◽  
Weiqing Wu ◽  
Xiangqing Liao ◽  
Min Zhao

Gastric cancer is one of the most common malignancies ranks as the second leading cause of cancer-related mortality in the world. Cisplatin (DDP) is commonly used for gastric cancer treatment, whereas recurrence and metastasis are common because of intrinsic and acquired DDP-resistance. The aim of this study is to examine the effects of berberine on the DDP-resistance in gastric cancer and explore the underling mechanisms. In this study, we established the DDP-resistant gastric cancer cells, where the IC50 values of DDP in the BGC-823/DDP and SGC-7901/DDP were significantly higher than that in the corresponding parental cells. Berberine could concentration-dependently inhibited the cell viability of BGC-823 and SGC-7901 cells; while the inhibitory effects of berberine on the cell viability were largely attenuated in the DDP-resistant cells. Berberine pre-treatment significantly sensitized BGC-823/DDP and SGC-7901/DDP cells to DDP. Furthermore, berberine treatment concentration-dependently down-regulated the multidrug resistance-associated protein 1 and multi-drug resistance-1 protein levels in the BGC-823/DDP and SGC7901/DDP cells. Interestingly, the cell apoptosis of BGC-823/DDP and SGC-7901/DDP cells was significantly enhanced by co-treatment with berberine and DDP. The results from animals also showed that berberine treatment sensitized SGC-7901/DDP cells to DDP in vivo. Mechanistically, berberine significantly suppressed the PI3K/AKT/mTOR in the BGC-823/DDP and SGC-7901/DDP cells treated with DDP. In conclusion, we observed that berberine sensitizes gastric cancer cells to DDP. Further mechanistic findings suggested that berberine-mediated DDP-sensitivity may be associated with reduced expression of drug transporters (multi-drug resistance-1 and multidrug resistance-associated protein 1), enhanced apoptosis and repressed PI3K/AKT/mTOR signaling.


FEBS Journal ◽  
2012 ◽  
Vol 279 (17) ◽  
pp. 3159-3165 ◽  
Author(s):  
Feng Yang ◽  
Jianwei Bi ◽  
Xuchao Xue ◽  
Luming Zheng ◽  
Kangkang Zhi ◽  
...  

2017 ◽  
Vol 13 (3) ◽  
pp. 317-325 ◽  
Author(s):  
Jian Wang ◽  
Qiong Niu ◽  
Ning Shi ◽  
Chengxia Liu ◽  
Haifeng Lian ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document