TRPM2 channel-mediated regulation of autophagy maintains mitochondrial function and promotes gastric cancer cell survival via the JNK-signaling pathway.
Almasi Shekoufeh,Kennedy Barry E,El-Aghil Mariam,Sterea Andra M,Gujar Shashi,Partida-Sánchez Santiago,El Hiani Yassine
The Journal of biological chemistry
A lack of effective treatment is one of the main factors contributing to gastric cancer-related death. Discovering effective targets and understanding their underlying anti-cancer mechanism are key to achieving the best response to treatment and to limiting side effects. Although recent studies have shown that the cation channel transient receptor potential melastatin-2 (TRPM2) is crucial for cancer cell survival, the exact mechanism remains unclear, limiting its therapeutic potential. Here, using molecular and functional assays, we investigated the role of TRPM2 in survival of gastric cancer cells. Our results indicated that TRPM2 knockdown in AGS and MKN-45 cells decreases cell proliferation and enhances apoptosis. We also observed that the TRPM2 knockdown impairs mitochondrial metabolism, indicated by a decrease in basal and maximal mitochondrial oxygen consumption rates and ATP production. These mitochondrial defects coincided with a decrease in autophagy and mitophagy, indicated by reduced levels of autophagy- and mitophagy-associated proteins ( ATGs, LC3A/B II, and BNIP3). Moreover, we found that TRPM2 modulates autophagy through a c-Jun N-terminal kinase (JNK)-dependent and mechanistic target of rapamycin-independent pathway. We conclude that in the absence of TRPM2, down-regulation of the JNK-signaling pathway impairs autophagy, ultimately causing the accumulation of damaged mitochondria and death of gastric cancer cells. Of note, by inhibiting cell proliferation and promoting apoptosis, the TRPM2 down-regulation enhanced the efficacy of paclitaxel and doxorubicin in gastric cancer cells. Collectively, we provide compelling evidence that TRPM2 inhibition may benefit therapeutic approaches for managing gastric cancer.
10.1074/jbc.M117.817635
Molecular mechanism of -induced autophagy in gastric cancer.
Zhang Fan,Chen Cong,Hu Jike,Su Ruiliang,Zhang Junqiang,Han Zhijian,Chen Hao,Li Yumin
Oncology letters
() is a gram-negative pathogen that colonizes gastric epithelial cells. The drug resistance rates of have dramatically increased, causing persistent infections. Chronic infection by is a critical cause of gastritis, peptic ulcers and even gastric cancer. In host cells, autophagy is stimulated to maintain cellular homeostasis following intracellular pathogen recognition by the innate immune defense system. However, -induced autophagy is not consistent during acute and chronic infection. Therefore, a deeper understanding of the association between infection and autophagy in gastric epithelial cells could aid the understanding of the mechanisms of persistent infection and the identification of autophagy-associated therapeutic targets for infection. The present review describes the role of and associated virulence factors in the induction of autophagy by different signaling pathways during acute infection. Additionally, the inhibition of autophagy in gastric epithelial cells during chronic infection was discussed. The present review summarized -mediated autophagy and provided insights into its mechanism of action, suggesting the induction of autophagy as a novel therapeutic target for persistent infection.
10.3892/ol.2019.10976
LC3A, LC3B and Beclin-1 Expression in Gastric Cancer.
Giatromanolaki Alexandra,Koukourakis Michael I,Georgiou Ioannis,Kouroupi Maria,Sivridis Efthimios
Anticancer research
BACKGROUND:The current study examined the key proteins involved in autophagosome formation and their prognostic role in gastric cancer. MATERIALS AND METHODS:Paraffin-embedded tissues from 121 consecutive patients treated with surgery for gastric cancer were analyzed immunohistochemically for the expression of autophagic proteins microtubule-associated proteins 1A/1B light chain 3A and 3B (LC3A, LC3B) and beclin-1 (encoded by BECN1 gene). Assessment of proliferative index using the MIB1 monoclonal antibody (recognizing an epitope of the Ki-67 antigen, encoded by the MK167 gene) and correlations with histopathological [corrected]. RESULTS:Strong cytoplasmic expression was noted for all studied proteins, although to a varying proportion, the median percentage being 30% for LC3A, and 40% for LC3B and beclin-1. The median score of LC3A stone-like structures (SLS) was 0.2 (range 0-1) and the median proliferative index was 30% (range=0-95%). A significant association between LC3A, LC3B and beclin-1 expression was confirmed (p<0.01). SLS score was higher in tumors of the gastro-esophageal junction (p=0.009), and beclin-1 was overexpressed in intestinal-type tumors (p=0.001). High SLS score (p=0.008) was significantly related to poor prognosis, and this finding persisted in multivariate analysis (hazard ratio(HR)=2.01, p=0.003). CONCLUSION:Intense autophagic activity, as assessed by LC3A immunostaining and SLS quantification, is a strong prognostic marker in gastric cancer and can be useful for clinical application.
10.21873/anticanres.13056
MKL1/miR-5100/CAAP1 loop regulates autophagy and apoptosis in gastric cancer cells.
Zhang Hui-Min,Li Hui,Wang Gen-Xin,Wang Jun,Xiang Yuan,Huang You,Shen Chao,Dai Zhou-Tong,Li Jia-Peng,Zhang Tong-Cun,Liao Xing-Hua
Neoplasia (New York, N.Y.)
PURPOSE:miR-5100 participates in the proliferation of lung cancer and pancreatic cancer cells, and participates in the differentiation of osteoblasts. However, the regulation of gastric cancer cells in gastric cancer cells remains unclear. EXPERIMENTAL DESIGN:The blood of patients was collected to detect the expression level of miR-5100, and the apoptosis and autophagy levels of cells were detected using western blot, flow cytometry, and confocal. At the same time, in vitro tumor formation experiments in nude mice were used to verify the results of in vitro experiments. RESULTS:The expression of miR-5100 is related to the prognosis of gastric cancer, miR-5100 can enhance the apoptosis level of gastric cancer cells and inhibit the occurrence of autophagy by targeting CAAP1. MKL1 can inhibit the apoptosis of gastric cancer cells and promote the occurrence of autophagy by targeting CAAP1. At the same time, MKL1 can also increase the expression of miR-5100. CONCLUSIONS:Our research reveals the mechanism by which the MKL1/miR-5100/CAAP1 loop regulates apoptosis and autophagy levels in gastric cancer cells, and miR-5100 is expected to become a new potential target for gastric cancer treatment.
10.1016/j.neo.2020.03.001
Autophagy in Helicobacter pylori Infection and Related Gastric Cancer.
Castaño-Rodríguez Natalia,Kaakoush Nadeem O,Goh Khean-Lee,Fock Kwong Ming,Mitchell Hazel M
Helicobacter
BACKGROUND:Autophagy, a degradation pathway in which cytoplasmic content is engulfed and degraded by lysosomal hydrolases, plays a pivotal role in infection and inflammation. Given that defects in autophagy lead to increased susceptibility to infection, we investigated the role of autophagy in Helicobacter pylori-related gastric cancer (GC). MATERIALS AND METHODS:Gene expression of 84 molecules was examined through quantitative real-time PCR in gastric epithelial cells (AGS) and macrophages (THP-1) upon exposure to H. pylori GC026 (GC) and 26695 (gastritis). Further, ATG16L1 rs2241880, IRGM rs13361189, and IRGM rs4958847, polymorphisms that have been investigated in relation to H. pylori infection or GC in Caucasians, were detected by MALDI-TOF mass spectrometry in 304 ethnic Chinese (86 noncardia GC cases/218 functional dyspepsia controls). RESULTS:Gene expression analyses showed twenty-eight molecules involved in vesicle nucleation, elongation, and maturation to be significantly down-regulated in H. pylori GC026-challenged AGS cells. Further, core autophagy proteins and autophagy regulators were differentially expressed in H. pylori-challenged THP-1-derived macrophages. Analyses of the selected polymorphisms showed that ATG16L1 rs2241880 increased the risk of GC (OR: 2.38, 95% CI: 1.34-4.24) and H. pylori infection (OR: 1.49, 95% CI: 1.02-2.16) while IRGM rs4958847 decreased GC risk (OR: 0.26, 95% CI: 0.09-0.74) in ethnic Chinese, these effect sizes being especially strong in H. pylori-infected individuals (ATG16L1 rs2241880 and IRGM rs13361189). CONCLUSIONS:Our findings indicate that highly virulent H. pylori strains markedly modulate autophagy in the host cell. Further, for the first time, autophagy polymorphisms were associated with GC in Chinese, a high GC-risk population.
10.1111/hel.12211
Identification and validation of an individualized autophagy-clinical prognostic index in gastric cancer patients.
Cancer cell international
BACKGROUND:The purpose of this study is to perform bioinformatics analysis of autophagy-related genes in gastric cancer, and to construct a multi-gene joint signature for predicting the prognosis of gastric cancer. METHODS:GO and KEGG analysis were applied for differentially expressed autophagy-related genes in gastric cancer, and PPI network was constructed in Cytoscape software. In order to optimize the prognosis evaluation system of gastric cancer, we established a prognosis model integrating autophagy-related genes. We used single factor Cox proportional risk regression analysis to screen genes related to prognosis from 204 autophagy-related genes in The Atlas Cancer Genome (TCGA) gastric cancer cohort. Then, the generated genes were applied to the Least Absolute Shrinkage and Selection Operator (LASSO). Finally, the selected genes were further included in the multivariate Cox proportional hazard regression analysis to establish the prognosis model. According to the median risk score, patients were divided into high-risk group and low-risk group, and survival analysis was conducted to evaluate the prognostic value of risk score. Finally, by combining clinic-pathological features and prognostic gene signatures, a nomogram was established to predict individual survival probability. RESULTS:GO analysis showed that the 28 differently expressed autophagy-related genes was enriched in cell growth, neuron death, and regulation of cell growth. KEGG analysis showed that the 28 differently expressed autophagy-related genes were related to platinum drug resistance, apoptosis and p53 signaling pathway. The risk score was constructed based on 4 genes (GRID2, ATG4D,GABARAPL2, CXCR4), and gastric cancer patients were significantly divided into high-risk and low-risk groups according to overall survival. In multivariate Cox regression analysis, risk score was still an independent prognostic factor (HR = 1.922, 95% CI = 1.573-2.349, P < 0.001). Cumulative curve showed that the survival time of patients with low-risk score was significantly longer than that of patients with high-risk score (P < 0.001). The external data GSE62254 proved that nomograph had a great ability to evaluate the prognosis of individual gastric cancer patients. CONCLUSIONS:This study provides a potential prognostic marker for predicting the prognosis of GC patients and the molecular biology of GC autophagy.
10.1186/s12935-020-01267-y
Chaperone-mediated autophagy regulates proliferation by targeting RND3 in gastric cancer.
Zhou Jinfeng,Yang Jianjun,Fan Xing,Hu Sijun,Zhou Fenli,Dong Jiaqiang,Zhang Song,Shang Yulong,Jiang Xiaoming,Guo Hao,Chen Ning,Xiao Xiao,Sheng Jianqiu,Wu Kaichun,Nie Yongzhan,Fan Daiming
Autophagy
LAMP2A is the key protein of chaperone-mediated autophagy (CMA), downregulation of LAMP2A leads to CMA blockade. CMA activation has been implicated in cancer growth, but the exact mechanisms are unclear. Elevated expression of LAMP2A was found in 8 kinds of tumors (n=747), suggesting that LAMP2A may have an important role in cancer progression. Unsurprisingly, LAMP2A knockdown in gastric cancer (GC) cells hindered proliferation, accompanied with altered expression of cell cycle-related proteins and accumulation of RND3/RhoE. Interactomic and KEGG analysis revealed that RND3 was a putative CMA substrate. Further study demonstrated that RND3 silencing could partly rescue the proliferation arrest induced by LAMP2A knockdown; RND3 was increased upon lysosome inhibition via both chemicals and LAMP2A-shRNA; Furthermore, RND3 could interact with CMA components HSPA8 and LAMP2A, and be engulfed by isolated lysosomes. Thus, constant degradation of RND3 by CMA is required to sustain rapid proliferation of GC cells. At last, the clinical significance of LAMP2A was explored in 593 gastric noncancerous lesions and 173 GC tissues, the results revealed that LAMP2A is a promising biomarker for GC early warning and prognosis of female GC patients.
10.1080/15548627.2015.1136770
The microRNA-423-3p-Bim Axis Promotes Cancer Progression and Activates Oncogenic Autophagy in Gastric Cancer.
Kong Pengfei,Zhu Xiaofeng,Geng Qirong,Xia Liangping,Sun Xiaowei,Chen Yingbo,Li Wei,Zhou Zhiwei,Zhan Youqing,Xu Dazhi
Molecular therapy : the journal of the American Society of Gene Therapy
Human serum microRNAs (miRNAs) have been shown to serve as disease fingerprints for predicting survival of cancer patients. However, the roles of specific miRNAs involved in gastric cancer (GC) are largely unknown. In this study, miRNA profiling was performed on sera obtained from six patients in good- and poor-survival groups. Expression of miR-423-3p was validated by quantitative RT-PCR in another 67 GC serum samples and paired normal and cancerous gastric tissues. Luciferase reporter assays were used to identify the target gene Bcl-2-interacting mediator of cell death (Bim). As a result, between the good-survival and poor-survival groups, the expression of nine serum miRNAs was altered more than two-fold. Among these, miR-423-3p was significantly increased in the poor-survival group, and its overexpression in GC tissues predicted poor survival in 119 patients with GC. miR-423-3p was found to promote cell proliferation, migration, and invasion in cell lines and animal models. Mechanistically, knockdown of the autophagy-related gene (Atg) 7 rescued the GC-promoting effect of miR-423-3p. In conclusion, miR-423-3p activates oncogenic and Beclin-1-dependent autophagy and promotes GC progression by reducing the expression of Bim. The newly identified miR-423-3p-Bim axis might be a potential therapeutic target in GC.
10.1016/j.ymthe.2017.01.013
MicroRNA-183 affects the development of gastric cancer by regulating autophagy via MALAT1-miR-183-SIRT1 axis and PI3K/AKT/mTOR signals.
Li Huiying,He Chengyan,Wang Xuekui,Wang Hai,Nan Guangxian,Fang Ling
Artificial cells, nanomedicine, and biotechnology
Gastric cancer (GC) remains to be a familiar malignant tumor with poor prognosis and daunting impacts on global health. We planned to grab the latent impacts of microRNA-183 in regulating cell autophagy, thus to clarify its possible regulatory principle in GC. The miR-183 level in GC tissues and cell lines was investigated. The impacts of miR-183 dysregulation on cell biological performances including viability, apoptosis and autophagy of GC cell lines including SGC-7901 were detected. Also, cells were disposed with 3-methyladenine (3-MA, an autophagy inhibition) before dysregulation of miR-183 to further investigate the correlation between cell autophagy and viability or apoptosis. Furthermore, the regulatory mechanisms between miR-183 and metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), silent mating type information regulation 1 (SIRT1) or PI3K/AKT/mTOR pathway were explored. miR-183 was under-expressed both in GC tissues and in cell lines. miR-183 mimic alone depressed SGC-7901 cell viability and enhanced cell apoptosis and autophagy, whereas miR-183 inhibitor exhibited opposite effects. Moreover, the impacts of miR-183 on SGC-7901 cell viability and apoptosis were mediated by affecting the activation of autophagy. Our results indicate that miR-183 is under-expressed in GC cells and depression of miR-183 may enhance GC cell viability and inhibit cell apoptosis by affecting the activation of cell autophagy. MALAT1-miR-183-SIRT1 axis and PI3K/AKT/mTOR pathway may be mechanisms to mediate autophagy in GC. miR-183 may serve as a towardly therapeutic target for GC.
10.1080/21691401.2019.1642903
Autophagy regulation and its role in gastric cancer and colorectal cancer.
Zhou Huangyan,Yuan Min,Yu Qiongfang,Zhou Xiaoyan,Min Weiping,Gao Dian
Cancer biomarkers : section A of Disease markers
BACKGROUND:Autophagy is associated with the occurrence, development, cellular adaptation, progression, treatment and prognosis of gastric cancer (GC) and colorectal cancer (CRC). The effect of autophagy in these two cancers has attracted our attention. OBJECTIVE:The aim of this study was to describe the functional and regulatory mechanisms associated with autophagy in GC and CRC. METHODS:We reviewed recent publications describing the role of autophagy in GC and CRC, including the functional characteristics, clinical significance and regulatory mechanisms. RESULTS:Autophagy plays context-dependent dual roles in the development and progression of GC and CRC. It can either promote tumor growth and cell survival or can contribute to tumor suppression and promote cell death. Both of these effects employ complex regulatory networks, such as those mediated by p53, PI3K/Akt/mTOR, Ras and microRNA. Among the cellular process associated with these pathways, autophagy is a potential target for anti-tumor therapy. CONCLUSION:Autophagy is associated with both tumorigenic and protective effects in cancer. However, the role of autophagy in GC and CRC remains unclear. Although the translation of the basic science of autophagy into clinical practice is a long process, the modulation of autophagy as a potential therapeutic approach in GC and CRC merits further investigation.
10.3233/CBM-160613
Inhibition of autophagy promotes metastasis and glycolysis by inducing ROS in gastric cancer cells.
Qin Wenjie,Li Chao,Zheng Wen,Guo Qingqu,Zhang Yuefeng,Kang Muxing,Zhang Bo,Yang Bin,Li Baozhong,Yang Haijun,Wu Yulian
Oncotarget
Autophagy defect has been shown to be correlated with malignant phenotype and poor prognosis of human cancers, however, the detailed mechanisms remain obscure. In this study, we investigated the biological changes induced by autophagy inhibition in gastric cancer. We showed that inhibition of autophagy in gastric cancer cells promotes epithelial-mesenchymal transition (EMT) and metastasis, alters metabolic phenotype from mitochondrial oxidative phosphorylation to aerobic glycolysis and converts cell phenotype toward malignant, which maybe further contribute to chemoresistance and poor prognosis of gastric cancer. We also identified that the EMT and metabolism alterations induced by autophagy inhibition were dependent on ROS-NF-κB-HIF-1α pathway. More importantly, scavenging of ROS by the antioxidant N-acetylcysteine (NAC) attenuated activation of NF-κB and HIF-1α in autophagy-deficient gastric cancer cells, and autophagy inhibition induced metastasis and glycolysis were also diminished by NAC in vivo. Taken together, our findings suggested that autophagy defect promotes metastasis and glycolysis of gastric cancer, and antioxidants could be used to improve disease outcome for gastric cancer patients with autophagy defect.
10.18632/oncotarget.5674
Autophagy and its role in gastric cancer.
Cao Yijing,Luo Yichen,Zou Juan,Ouyang Jun,Cai Zhihong,Zeng Xi,Ling Hui,Zeng Tiebing
Clinica chimica acta; international journal of clinical chemistry
Autophagy, which is tightly regulated by a series of autophagy-related genes (ATGs), is a vital intracellular homeostatic process through which defective proteins and organelles are degraded and recycled under starvation, hypoxia or other specific cellular stress conditions. For both normal cells and tumour cells, autophagy not only sustains cell survival but can also promote cell death. Autophagy-related signalling pathways include mTOR-dependent pathways, such as the AMPK/mTOR and PI3K/Akt/mTOR pathways, and non-mTOR dependent pathways, such as the P53 pathway. Additionally, autophagy plays a dual role in gastric carcinoma (GC), including a tumour-suppressor role and a tumour-promoter role. Long-term Helicobacter pylori infection can impair autophagy, which may eventually promote tumourigenesis of the gastric mucosa. Moreover, Beclin1, LC3 and P62/SQSTM1 are regarded as autophagy-related markers with GC prognostic value. Autophagy inhibitors and autophagy inducers show promise for GC treatment. This review describes research progress regarding autophagy and its significant role in gastric cancer.
10.1016/j.cca.2018.11.028
Clinicopathological Correlations of Autophagy-related Proteins LC3, Beclin 1 and p62 in Gastric Cancer.
Masuda G O,Yashiro Masakazu,Kitayama Kishu,Miki Yuichiro,Kasashima Hiroaki,Kinoshita Haruhito,Morisaki Tamami,Fukuoka Tatshunari,Hasegawa Tsuyoshi,Sakurai Katsunobu,Toyokawa Takahiro,Kubo Naoshi,Tanaka Hiroaki,Muguruma Kazuya,Masaichi Ohira,Hirakawa Kosei
Anticancer research
AIM:This study evaluated the clinicopathological significance of autophagy, an intracellular degradation system, in gastric cancer. MATERIALS AND METHODS:The expression levels of three autophagy-related proteins, namely light chain 3 (LC3), Beclin 1 and p62, were analyzed by immunohistochemistry using samples from 510 patients with primary gastric cancer. RESULTS:LC3, Beclin 1, and p62 expression was positive in 79 (15.5%), 126 (24.7%) and 251 (49.2%) out of 510 carcinomas, respectively. Autophagy was defined when samples were positive for at least two out of the three proteins. Autophagy-positive cases were 113 (22.1%) out of the 510. Autophagy determined by LC3, Beclin 1, and p62 significantly correlated with lymph node metastasis, vessel invasion, and hepatic metastasis. A Kaplan-Meier survival curve showed that autophagy was significantly associated with poor survival of patients with gastric cancer, especially for those with disease at stage I. Multivariate analysis indicated that autophagy was an independent prognostic factor. CONCLUSION:Autophagy promotes the progression of gastric cancer at an early clinical stage.
Functional role of autophagy in gastric cancer.
Qian Hao-ran,Yang Yi
Oncotarget
Autophagy is a highly regulated catabolic pathway responsible for the degradation of long-lived proteins and damaged intracellular organelles. Perturbations in autophagy are found in gastric cancer. In host gastric cells, autophagy can be induced by Helicobacter pylori (or H. pylori) infection, which is associated with the oncogenesis of gastric cancer. In gastric cancer cells, autophagy has both pro-survival and pro-death functions in determining cell fate. Besides, autophagy modulates gastric cancer metastasis by affecting a wide range of pathological events, including extracellular matrix (ECM) degradation, epithelial-to-mesenchymal transition (EMT), tumor angiogenesis, and tumor microenvironment. In addition, some of the autophagy-related proteins, such as Beclin 1, microtubule-associated protein 1 light chain 3 (MAP1-LC3), and p62/sequestosome 1 (SQSTM1) have certain prognostic values for gastric cancer. In this article, we review the recent studies regarding the functional role of autophagy in gastric cancer.
10.18632/oncotarget.7508
Down-regulation of ASIC1 suppressed gastric cancer via inhibiting autophagy.
Zhang Qiong,Wu Shiwu,Zhu Jinhai,Chai Damin,Gan Huaiyong
Gene
As autophagy has anti-apoptosis effect and accelerates cell survival, many studies start to target autophagy as a therapeutic strategy for cancer. Acid-sensing ion channels (ASICs) was reported to activate autophagy. However, whether ASICs can regulate gastric cancer through autophagy is unknown. The differentially expressed genes in normal gastric tissue and gastric cancer tissue in patients were investigated by RNA-seq. Expression of ASIC1 and autophagy related 5 (ATG5) was further confirmed by real-time PCR. Effects of knockdown expression of ASIC1 and ATG5 on the growth of gastric SGC-7901 cells were assayed by CCK-8 kit. The animal survival rate and tumor volume in murine heterotopic xenograft model was assayed. The expression of autophagy related genes was enriched in gastric cancer tissue in patients, including ASIC1 and ATG5. Knockdown expression of ASIC1 and ATG5 inhibits the growth of SGC-7901 cells, respectively. ASIC1 regulates ATG5 gene expression in SGC-7901 cells. ASIC1 knockdown extended the survival rate of animals and inhibited the tumor volume in the murine heterotopic xenograft model. This study showed that downregulation of ASIC1 inhibits gastric cancer growth via decreasing autophagy, therefore strongly suggests a therapeutic role for ASIC1 in gastric cancer.
10.1016/j.gene.2017.01.014